WO2023210457A1 - Refrigeration device - Google Patents

Refrigeration device Download PDF

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Publication number
WO2023210457A1
WO2023210457A1 PCT/JP2023/015550 JP2023015550W WO2023210457A1 WO 2023210457 A1 WO2023210457 A1 WO 2023210457A1 JP 2023015550 W JP2023015550 W JP 2023015550W WO 2023210457 A1 WO2023210457 A1 WO 2023210457A1
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WO
WIPO (PCT)
Prior art keywords
refrigerant
compressor
pressure
control device
air conditioner
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PCT/JP2023/015550
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French (fr)
Japanese (ja)
Inventor
一彦 三原
雅也 本間
晃 鶸田
Original Assignee
パナソニックＩｐマネジメント株式会社
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Publication of WO2023210457A1 publication Critical patent/WO2023210457A1/en

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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B1/00—Compression machines, plants or systems with non-reversible cycle
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B49/00—Arrangement or mounting of control or safety devices
    • F25B49/02—Arrangement or mounting of control or safety devices for compression type machines, plants or systems

Definitions

  • the present invention relates to a refrigeration device.
  • Patent Document 1 discloses a refrigerator using low GWP (Global Warming Potential).
  • the refrigerator of Patent Document 1 uses trans-1,2-difluoroethylene (HFO-1132(E)), 2,3,3,3-tetrafluoro-1-propene (R1234yf), and trifluoroethylene (HFO-1123). ) etc.
  • the present disclosure provides a refrigeration system that can suppress the influence of the disproportionation reaction in a refrigeration cycle when the disproportionation reaction of the refrigerant occurs.
  • the refrigeration system includes a compressor, a heat source side heat exchanger, a user side heat exchanger, an expansion mechanism, a heating operation state in which the user side heat exchanger operates as a condenser, and a heating operation state in which the user side heat exchanger operates as a condenser.
  • a switching valve that switches between a cooling operating state in which the exchanger operates as a condenser; and a control device; the control device uses a working medium containing ethylene-based fluoroolefin as a refrigerant; If it is detected that the pressure of the working medium in the high pressure section including the compressor and the condenser has increased to a threshold value or more, the switching valve is controlled to switch from the heating operation state to the cooling operation state. Make the switch.
  • the refrigeration device achieves low GWP by using a working medium containing ethylene-based fluoroolefins as a refrigerant, and can suppress the effects when a refrigerant disproportionation reaction occurs.
  • FIG. 1 is a diagram showing the configuration of an air conditioner according to Embodiment 1 of the present invention.
  • Figure 2 is a diagram showing the configuration of the compressor.
  • FIG. 3 is a diagram showing the configuration of an air conditioner according to Embodiment 1 of the present invention.
  • FIG. 4 is a flowchart showing the operation of the air conditioner according to the first embodiment.
  • FIG. 5 is a diagram showing the configuration of an air conditioner according to Embodiment 2 of the present invention.
  • FIG. 6 is a diagram showing the configuration of an air conditioner according to Embodiment 3 of the present invention.
  • FIG. 7 is a diagram showing the configuration of an air conditioner according to Embodiment 4 of the present invention.
  • FIG. 8 is a diagram showing the configuration of an air conditioner according to Embodiment 5 of the present invention.
  • the present disclosure provides a refrigeration system that can suppress the influence of the disproportionation reaction in a refrigeration cycle when the disproportionation reaction of the refrigerant occurs.
  • a refrigeration system that can suppress the influence of the disproportionation reaction in a refrigeration cycle when the disproportionation reaction of the refrigerant occurs.
  • FIGS. 1 to 4 Embodiment 1 will be described below using FIGS. 1 to 4.
  • FIGS. 1 to 4. [1-1. Configuration of air conditioner] 1 and 3 are diagrams showing the configuration of air conditioner 1 in Embodiment 1, and FIG. 2 is a diagram showing the configuration of compressor 100 included in air conditioner 1.
  • the air conditioner 1 shown in FIGS. 1 and 3 is an example to which the refrigeration circuit of the present invention is applied.
  • FIG. 1 shows a cooling operation state of the air conditioner 1
  • FIG. 3 shows a heating operation state of the air conditioner 1.
  • the air conditioner 1 includes a compressor 100, heat exchangers 11a and 11b, expansion valves 12a and 12b, a heat exchanger 13, an expansion valve 14, a gas-liquid separator 15, a valve 16, four-way valves 21 and 22, and Equipped with refrigerant piping to connect.
  • the air conditioner 1 also includes a control device 10 that controls the expansion valves 12a, 12b, the expansion valve 14, the valve 16, and the four-way valves 21, 22.
  • the four-way valves 21 and 22 correspond to an example of a switching valve.
  • the compressor 100 includes a suction port 104, a discharge pipe 105, and an injection section 125, as will be described later with reference to FIG.
  • the compressor 100 sucks and compresses refrigerant through a suction port 104, and discharges high-pressure refrigerant through a discharge pipe 105.
  • the heat exchangers 11a and 11b are user-side heat exchangers that are installed in the indoor unit and perform cooling and heating of the conditioned space. Heat exchanger 11a and heat exchanger 11b are connected in parallel.
  • the heat exchanger 13 is a heat source side heat exchanger installed in the outdoor unit. Each of heat exchanger 11a, heat exchanger 11b, and heat exchanger 13 is provided with a fan.
  • a pipe 41 connected to the suction port 104 of the compressor 100, a pipe 42 connected to the discharge pipe 105, a pipe 44 connected to the heat exchangers 11a and 11b, and a pipe 46 connected to the heat exchanger 13 are connected to the four-way valve 21.
  • Piping 41 corresponds to an example of suction piping.
  • the pipe 42 corresponds to an example of a discharge pipe.
  • the four-way valve 21 switches connections between the pipes 41 , 42 , 44 , and 46 under the control of the control device 10 .
  • a pipe 45 connected to the heat exchangers 11a and 11b, a pipe 47 connected to the heat exchanger 13, and a pipe 48 and a pipe 49 connected to the gas-liquid separator 15 are connected to the four-way valve 22.
  • Piping 49 is a piping that allows the refrigerant to flow into the gas-liquid separator 15
  • piping 48 is a piping that allows the refrigerant to flow out from the gas-liquid separator 15.
  • the gas-liquid separator 15 is a tank that stores the refrigerant flowing in from the pipe 48 and can separate and take out the liquid refrigerant and the gas refrigerant.
  • the gas-liquid separator 15 corresponds to an example of a refrigerant storage section.
  • the four-way valve 22 switches connections between the pipes 45 , 47 , 48 , and 49 under the control of the control device 10 .
  • FIG. 1 the flow of refrigerant in the cooling operation state is shown by arrows labeled RC.
  • FIG. 2 the flow of the refrigerant in the heating operation state is shown by arrows labeled RH.
  • FIGS. 1 to 3 and FIGS. 5 to 7, which will be described later the flow of the refrigerant that is common between the cooling operation state and the heating operation state is shown by an arrow with a symbol R.
  • the four-way valve 21 connects the pipe 42 and the pipe 46, and connects the pipe 44 and the pipe 41.
  • the four-way valve 22 connects the piping 47 and the piping 49, and connects the piping 48 and the piping 45.
  • the refrigerant discharged from the compressor 100 into the discharge pipe 105 flows into the heat exchanger 13 via the pipe 42 and the four-way valve 21, and is condensed in the heat exchanger 13. . That is, the heat exchanger 13 functions as a condenser in the cooling operation state.
  • the refrigerant condensed in the heat exchanger 13 flows into the gas-liquid separator 15 through the pipe 47, the four-way valve 22, and the pipe 49.
  • liquid refrigerant is supplied from the gas-liquid separator 15 to the expansion valves 12a and 12b through the pipe 48 and the four-way valve 22.
  • the expansion valve 12a reduces the pressure of the refrigerant and supplies it to the heat exchanger 11a
  • the expansion valve 12b reduces the pressure of the refrigerant and supplies it to the heat exchanger 11b.
  • the heat exchangers 11a and 11b function as evaporators during cooling operation, and vaporize the refrigerant whose pressure has been reduced by the expansion valves 12a and 12b.
  • the refrigerant vaporized in the heat exchangers 11a and 11b is sent to the compressor 100 through the pipe 44, the four-way valve 21, and the pipe 41.
  • the four-way valve 21 connects the piping 42 and the piping 44, and connects the piping 46 and the piping 41.
  • the four-way valve 22 connects the piping 47 and the piping 48 and connects the piping 49 and the piping 45.
  • the refrigerant discharged from the discharge pipe 105 flows into the heat exchangers 11a and 11b through the pipe 42 and the four-way valve 21, and is condensed in the heat exchangers 11a and 11b. That is, in the heating operation state, the heat exchangers 11a and 11b function as condensers.
  • the refrigerant condensed in the heat exchangers 11a and 11b flows into the gas-liquid separator 15 through the pipe 45, the four-way valve 22, and the pipe 49.
  • liquid refrigerant is supplied from the gas-liquid separator 15 to the expansion valve 14 through the pipe 48 and the four-way valve 22.
  • the expansion valve 14 reduces the pressure of the refrigerant and supplies it to the heat exchanger 13 .
  • the heat exchanger 13 functions as an evaporator in the heating operation state, and vaporizes the refrigerant whose pressure has been reduced by the expansion valve 14.
  • the refrigerant vaporized in the heat exchanger 13 is sucked into the suction port 104 through the pipe 46, the four-way valve 21, and the pipe 41.
  • the control device 10 includes a processor such as a microcontroller.
  • the control device 10 controls the air conditioner 1 by executing a program using a processor or by using programmed hardware functions.
  • the control device 10 controls the four-way valve 21 and the four-way valve 22 to switch between the cooling operation state and the heating operation state. Further, the control device 10 adjusts the opening degrees of the expansion valves 12a and 12b in the cooling operation state. The control device 10 adjusts the opening degree of the expansion valve 14 in the heating operation state.
  • the control device 10 executes control to open and close the valve 16 provided in the pipe 43.
  • the valve 16 is composed of an electric valve, a solenoid valve, or an expansion valve.
  • the control device 10 controls opening and closing of the valve 16 and adjusts the opening degree of the valve 16.
  • the air conditioner 1 may include one or more of a temperature sensor (not shown) that detects the temperature of the electric motor 110 and a temperature sensor (not shown) that detects the temperature of the refrigerant discharged by the compression mechanism 120. These temperature sensors are connected to the control device 10.
  • the control device 10 detects either or both of the temperature of the electric motor 110 and the temperature of the refrigerant discharged by the compression mechanism 120 by acquiring the detection value of the temperature sensor. Further, the control device 10 may calculate the pressure of the refrigerant discharged by the compression mechanism 120 based on the temperature of the refrigerant discharged by the compression mechanism 120.
  • the air conditioner 1 may include a pressure sensor that detects the pressure of the refrigerant discharged by the compression mechanism 120. Furthermore, the air conditioner 1 may include a heat exchanger temperature sensor (not shown) that detects the temperatures of the heat exchangers 11a, 11b, and the heat exchanger 13. In this case, the control device 10 may calculate the pressure and temperature of the refrigerant discharged by the compression mechanism 120 based on the detected value of the heat exchanger temperature sensor, or may be configured without the above-mentioned temperature sensor. .
  • the pipe 43 supplies gaseous refrigerant from the gas-liquid separator 15 to the compressor 100. Since the pipe 43 supplies the refrigerant stored in the gas-liquid separator 15 to the compressor 100 through a route different from the pipe 48 connected to the suction port 104, it can be called a bypass pipe. Piping 43 is connected to injection section 125 of compressor 100. The compressor 100 is cooled by supplying refrigerant to the injection section 125 through the pipe 43.
  • the injection unit 125 corresponds to an example of a refrigerant supply unit.
  • the pipe 43 corresponds to an example of a refrigerant pipe.
  • a relief valve 60 is provided in the pipe 42 connected to the discharge pipe 105.
  • a relief valve 60 is provided in the piping 42.
  • the relief valve 60 is a valve that automatically opens when the pressure of the refrigerant exceeds a preset pressure, and reduces the pressure in the compression chamber of the compression mechanism 120 and the discharge pipe 105.
  • the relief valve 60 corresponds to an example of pressure release means.
  • the relief valve 60 may be provided in the discharge pipe 105.
  • compressor 100 has a container 102. As shown in FIG. The container 102 houses a compression mechanism 120 that compresses refrigerant and an electric motor 110 that drives the compression mechanism 120. Electric motor 110 has a stator 111 and a rotor 112. A crankshaft 103 is connected to the rotor 112, and the crankshaft 103 is rotatably supported by bearings 107 and 108. Thereby, the rotor 112 is rotatably held together with the crankshaft 103.
  • the electric motor 110 is located, for example, in the lower part of the internal space of the container 102, and the compression mechanism 120 is located above the electric motor 110.
  • Refrigerating machine oil (not shown) is stored at the bottom of the container 102 .
  • the electric motor 110 is a so-called concentrated winding motor.
  • the stator 111 has teeth having three-phase stator windings and a yoke that connects the teeth, and the stator windings of the stator 111 are connected to an inverter-type drive circuit 116 by lead wires (not shown). be done.
  • the rotor 112 has a permanent magnet and rotates together with the crankshaft 103 by a rotating magnetic field generated by a current flowing through the stator 111.
  • Drive circuit 116 outputs a drive current to stator 111 under control of electric motor 110.
  • the compression mechanism 120 is, for example, a scroll type compression mechanism.
  • the compression mechanism 120 includes a fixed scroll 121 and an oscillating scroll 122 combined with the fixed scroll 121, and a space between the fixed scroll 121 and the oscillating scroll 122 functions as a compression chamber.
  • the compression mechanism 120 compresses the refrigerant by rotating the swinging scroll 122 together with the crankshaft 103.
  • the refrigerant compressed by the compression mechanism 120 is discharged through the discharge pipe 105.
  • the compressor 100 is a so-called internal low pressure type compressor in which a compression mechanism 120 sucks and compresses the refrigerant flowing into the container 102 through the suction port 104.
  • the refrigerant flowing into the container 102 from the suction port 104 is sucked into the compression mechanism 120 through an air gap, which is a space between the stator 111 and the rotor 112 of the electric motor 110, as shown by arrow RI.
  • the electric motor 110 is cooled by the refrigerant flowing through the air gap.
  • the injection part 125 is a tube that communicates between the inside and outside of the container 102, and the tip of the injection part 125 opens into the compression chamber of the compression mechanism 120.
  • the piping 43 is connected to the injection section 125 as described above, and gaseous refrigerant is supplied through the piping 43.
  • the refrigerant in the gas-liquid separator 15 is sucked into the compression mechanism 120.
  • the gaseous refrigerant is extracted from the gas-liquid separator 15, thereby reducing the pressure of the refrigerant in the gas-liquid separator 15 and causing the refrigerant to expand in the gas-liquid separator 15.
  • the injection part 125 may be opened inside the container 102 at or near a suction port through which the compression mechanism 120 sucks the refrigerant inside the container 102 . In this case as well, the effect of extracting the gaseous refrigerant from the gas-liquid separator 15 can be produced.
  • the refrigerant used in the air conditioner 1 is a working medium containing ethylene-based fluoroolefin.
  • ethylene-based fluoroolefins include 1,1,2-trifluoroethylene (HFO-1123), trans-1,2-difluoroethylene (HFO-1132(E)), and cis-1,2-difluoroethylene (HFO-1123).
  • the working medium may include two or more refrigerant components. That is, it may contain an ethylene-based fluoroolefin (for example, 1,1,2-trifluoroethylene) selected from the above examples and a second refrigerant component.
  • the second refrigerant component may include one or more refrigerants selected from hydrofluorocarbons (HFCs), hydrofluoroolefins (HFOs), saturated hydrocarbons, carbon dioxide, or other refrigerants.
  • hydrofluorocarbon examples include difluoromethane, difluoroethane, trifluoroethane, tetrafluoroethane, pentafluoroethane, pentafluoropropane, hexafluoropropane, heptafluoropropane, pentafluorobutane, and heptafluorocyclopentane.
  • hydrofluoroolefins include monofluoropropene, trifluoropropene, tetrafluoropropene, pentafluoropropene, and hexafluorobutene.
  • Saturated hydrocarbons include, for example, ethane, n-propane, cyclopropane, n-butane, cyclobutane, isobutane (2-methylpropane), methylcyclopropane, n-pentane, isopentane (2-methylbutane), neopentane (2,2 -dimethylpropane) and methylcyclobutane, but other hydrocarbons may also be used.
  • the second refrigerant component may include multiple components. That is, the second refrigerant component may include two or more refrigerant components selected from hydrofluorocarbons, hydrofluoroolefins, saturated hydrocarbons, carbon dioxide, and other refrigerants.
  • the working medium used as a refrigerant in the air conditioner 1 may contain a disproportionation inhibitor in addition to the refrigerant components.
  • Disproportionation inhibitors are, for example, saturated hydrocarbons.
  • the working medium may include a disproportionation inhibitor consisting of one or more components.
  • Saturated hydrocarbons utilized as disproportionation inhibitors include ethane, n-propane, cyclopropane, n-butane, cyclobutane, isobutane (2-methylpropane), methylcyclopropane, n-pentane, isopentane (2-methylbutane). ), neopentane (2,2-dimethylpropane), and methylcyclobutane, but other saturated hydrocarbons may also be used.
  • a particularly preferred disproportionation inhibitor is n-propane.
  • the disproportionation inhibitor may be, for example, a haloalkane having 1 to 2 carbon atoms.
  • haloalkanes having one carbon number, ie, halomethanes used as disproportionation inhibitors include (mono)iodomethane (CH 3 I), diiodomethane (CH 2 I 2 ), dibromomethane (CH 2 Br 2 ), and bromomethane.
  • haloalkane having 2 carbon atoms that is, haloethane, used as a disproportionation inhibitor
  • CF 3 CH 2 I 1,1,1-trifluoro-2-iodoethane
  • CH 3 CH 2 I monoiodoethane
  • CH 3 CH 2 Br monobromoethane
  • CH 3 CI 3 1,1,1-triiodoethane
  • the working medium may include a plurality of disproportionation inhibitors selected from the above-mentioned saturated hydrocarbons and the above-mentioned haloalkanes. Further, the working medium may contain one type of saturated hydrocarbon or may contain two or more types of saturated hydrocarbons. Further, the working medium may contain one type of haloalkane, or may contain two or more types of haloalkanes.
  • a preferred example of the working medium is a mixture containing 1,1,2-trifluoroethylene and n-propane.
  • This working medium may contain the second refrigerant component described above, or may contain other components.
  • Each of the above working media may contain unavoidable impurities.
  • Unavoidable impurities include various additives including stabilizers added for the purpose of stabilization during transportation and storage, residues or by-products of synthetic raw materials for refrigerant components, and substances mixed in for other reasons. Can be mentioned.
  • the mass ratio of 1,1,2-trifluoroethylene and n-propane contained in the working medium can be changed as appropriate.
  • the capacity of a refrigeration cycle is correlated to the mass ratio of refrigerant components contained in the working medium. Therefore, in order to maintain the performance of the refrigeration cycle, it is desirable that the working medium contains n-propane, which is a disproportionation inhibitor, in an amount of 40% by mass or less.
  • Ethylene-based fluoroolefins include, for example, ethylene-based fluoroolefins in which a disproportionation reaction occurs.
  • ethylene-based fluoroolefins as refrigerants, there are advantages of low GWP and high refrigerating capacity.
  • disproportionation reactions may occur under certain conditions.
  • the disproportionation reaction is known as a reaction in which radicals are generated from molecules contained in a refrigerant, and self-decomposition of the refrigerant progresses due to a chain reaction. When a disproportionation reaction occurs, it causes a sudden pressure increase in the refrigeration cycle.
  • the specific conditions under which the disproportionation reaction can occur include the refrigerant being at a high temperature, the refrigerant being under high pressure, and the refrigerant being exposed to an electrical discharge phenomenon.
  • the disproportionation reaction of the refrigerant can be prevented or suppressed by eliminating or preventing any of high temperature, high pressure, and discharge phenomena.
  • a typical example of a discharge phenomenon that induces a disproportionation reaction is a short circuit that occurs between stator windings of stator 111 in electric motor 110. This type of short circuit is called a layer short or a layer short.
  • the air conditioner 1 of this embodiment includes a configuration that suppresses the disproportionation reaction of the refrigerant.
  • Compressor 100 is of internal low pressure type. Therefore, since the refrigerant pressure inside the container 102 is equal to the pressure on the suction side of the compression mechanism 120, the refrigerant is unlikely to reach a high temperature and high pressure state in and around the electric motor 110. Therefore, even if a layer short occurs in the electric motor 110, a disproportionation reaction of the refrigerant is unlikely to be induced.
  • the refrigerant sucked in from the suction port 104 passes through the air gap between the stator 111 and the rotor 112 and reaches the compression mechanism 120, so the temperature of the electric motor 110 increases due to the refrigerant passing through the air gap. is suppressed. Therefore, the electric motor 110 and the refrigerant around it are unlikely to reach a high temperature and high pressure state, so even if a layer short occurs in the electric motor 110, a disproportionation reaction of the refrigerant is unlikely to be induced.
  • the air conditioner 1 includes a pipe 43 and an injection section 125 that supply liquid refrigerant to the compression chamber of the compressor 100.
  • the control device 10 opens the valve 16 when the temperature of the compressor 100 satisfies a preset condition, and causes the injection section 125 to supply refrigerant.
  • the preset condition is, for example, that the temperature of the compressor 100 is equal to or higher than a threshold value.
  • the temperature of the compressor 100 is the temperature of the electric motor 110 or the temperature of the refrigerant discharged from the compression mechanism 120.
  • the control device 10 opens the valve 16 when detecting that the temperature of the electric motor 110 or the temperature of the refrigerant discharged from the compression mechanism 120 exceeds a threshold value. Thereby, the compression mechanism 120 can be cooled, and the disproportionation reaction can be suppressed.
  • the valve 16 when the valve 16 is opened, the pressure of the refrigerant in the gas-liquid separator 15 is reduced as the refrigerant flows out from the gas-liquid separator 15 to the pipe 43, and the refrigerant is expanded in the gas-liquid separator 15. can be done.
  • the gas-liquid separator 15 functions as a type of heat exchanger, and therefore, the gas-liquid separator 15 can be called an intercooler, for example. Due to this action, the refrigerant discharged from the compressor 100 is depressurized in two stages in the expansion valve 14 and the gas-liquid separator 15 when the air conditioner 1 is in a cooling operation state. That is, the expansion valve 14 and the gas-liquid separator 15 constitute a two-stage expansion mechanism.
  • the region where the refrigerant becomes high temperature and high pressure in the cooling operation state is the region indicated by the symbol HP in FIG. 1 . Since the expansion valve 14 and the gas-liquid separator 15 constitute a two-stage expansion mechanism, the region HP can be limited to a narrow range. Therefore, even if a refrigerant disproportionation reaction occurs, the range in which the refrigerant chain reaction propagates can be narrowed. Furthermore, by configuring a two-stage expansion process, the temperature of the compression mechanism 120 can be lowered, and the disproportionation reaction can be suppressed more effectively.
  • the air conditioner 1 can control the opening and closing of the valve 16 by the control device 10, and for example, closes the valve 16 in a state where the possibility of a disproportionation reaction occurring is low. Therefore, the operating efficiency of the air conditioner 1 can be improved.
  • the air conditioner 1 includes a relief valve 60. Therefore, even if a disproportionation reaction occurs, the relief valve 60 opens in response to the increase in refrigerant pressure accompanying the disproportionation reaction, thereby preventing an excessive increase in pressure in the refrigeration cycle.
  • the disproportionation reaction of the refrigerant is suppressed.
  • a refrigerant containing an inert disproportionation inhibitor suppresses the disproportionation reaction of ethylene-based fluoroolefins due to its thermodilution effect.
  • certain disproportionation inhibitors scavenge radicals, which are active intermediates produced in disproportionation reactions. Thereby, it is possible to prevent a chain reaction by trapping radicals generated in the initial stage of the reaction, and to suppress the propagation of the chain reaction. These effects can suppress the disproportionation reaction of the refrigerant.
  • control by control device Here, a description will be given of control by which the control device 10 suppresses the disproportionation reaction of the refrigerant. As described above, the control device 10 controls the opening of the valve 16 when the temperature of the compressor 100 satisfies a preset condition. Further, the control device 10 suppresses the disproportionation reaction by operating the four-way valves 21, 22 and other valves.
  • FIG. 4 is a flowchart showing the operation of the control device 10.
  • the control device 10 monitors whether the refrigerant pressure in the high pressure section of the air conditioner 1 has increased to a threshold value or more (step S11).
  • the high-pressure section is a range in which high-pressure refrigerant flows in the air conditioner 1, and includes, for example, any one of the compression mechanism 120, the discharge pipe 105, and the region HP shown in FIG.
  • the control device 10 determines the pressure of the refrigerant discharged from the compression mechanism 120.
  • step S11 If the pressure is lower than the threshold (step S11; NO), the control device 10 continues monitoring in step S11 at predetermined time intervals.
  • the threshold value is set in advance in the control device 10.
  • the threshold value is the pressure at which the refrigerant disproportionation reaction in the compressor 100 is estimated to have occurred, or the value of the pressure at which the disproportionation reaction is likely to occur. If the control device 10 determines that the pressure of the refrigerant discharged from the compressor 100 has increased above the threshold value (step S11; YES), there is a possibility that a refrigerant disproportionation reaction has occurred in the high pressure section of the air conditioner 1. is high. In this case, although not shown in FIG. 4, the control device 10 does not perform control to open the valve 16 and cause the refrigerant to flow from the injection section 125 into the compression mechanism 120. Furthermore, the control device 10 may perform control to close the valve 16.
  • control device 10 determines whether the air conditioner 1 is in heating operation (step S12). When the air conditioner 1 is in heating operation (step S12; YES), the control device 10 operates the four-way valve 21 and the four-way valve 22 to switch the air conditioner 1 to cooling operation (step S13).
  • control device 10 controls the valve to be controlled. Control is performed to close the opening to the first opening degree (step S14). In step S14, the control device 10 closes at least the expansion valve 14 to the first opening degree. The control device 10 may perform control to close the expansion valves 12a and 12b to the first opening degree in step S14.
  • the first opening degree is a predetermined opening degree at which the valve is in an open state rather than a fully closed state.
  • the first opening degree may be a value set corresponding to each valve, or may be a set value common to all valves. For example, when fully opening is 100%, the first opening degree can be 10%.
  • the control device 10 closes the valve, propagation of the disproportionation reaction beyond the valve can be suppressed. Further, if the valve is fully closed, the pressure increase due to the disproportionation reaction may change more rapidly, so it is effective to set the valve to the first opening degree instead of fully closing the valve.
  • the control device 10 monitors whether the increase in pressure in the high pressure section has stopped (step S15). If the increase in pressure has not stopped (step S15; NO), monitoring in step S15 is continued at predetermined time intervals. If it is determined that the increase in pressure has stopped (step S15; YES), the control device 10 performs control to close the valve, which was closed to the first opening degree in step S14, to a fully closed state (step S16). After that, the control device 10 executes notification (step S17).
  • the notification in step S17 is not limited as long as it can notify the administrator of the air conditioner 1 of the occurrence of the disproportionation reaction.
  • the control device 10 may notify the device that manages the air conditioner 1 of the occurrence of the disproportionation reaction, or cause the display of the remote control device that operates the air conditioner 1 to display the occurrence of the disproportionation reaction.
  • the display may be displayed on a display included in the indoor unit of the air conditioner 1.
  • sounds and images may be output under the control of the control device 10.
  • the control device 10 may stop the compressor 100 at any of steps S12 to S16.
  • step S11 and step S15 described above the control device 10 estimates the pressure of the refrigerant discharged from the compressor 100 based on the temperature of the refrigerant discharged from the compressor 100 and the temperatures of the heat exchangers 11a, 11b and the heat exchanger 13. , the estimated pressure may be determined.
  • control device 10 determines the pressure of the refrigerant discharged from the compressor 100 in step S11 and step S15, but this is just an example.
  • the control device 10 may make the determination based on the temperature of the refrigerant discharged from the compressor 100, for example.
  • the control device 10 may directly detect the temperature of the refrigerant discharged from the compressor 100 using a temperature sensor, or may detect the temperature of the refrigerant discharged from the compressor 100 based on the pressure of the discharged refrigerant or the temperature of the heat exchangers 11a, 11b, and the heat exchanger 13.
  • the determination may be made based on the estimated temperature of the refrigerant discharged from the compressor 100.
  • the four-way valves 21 and 22 of the air conditioner 1 are constituted by low differential pressure operating type four-way valves or electromagnetic on-off valves.
  • pilot-type four-way switching valves are used as the four-way valves 21 and 22
  • the heating operation state can be quickly switched to the cooling operation state in step S13. It has the advantage of being carried out.
  • the air conditioner 1 of the first embodiment includes the compressor 100, the heat exchanger 13 which is the heat source side heat exchanger, and the heat exchangers 11a and 11b which are the usage side heat exchangers.
  • the air conditioner 1 includes four-way valves 21 and 22 that switch between a heating operation state in which the heat exchangers 11a and 11b operate as condensers and a cooling operation state in which the heat exchanger 13 operates as a condenser, and a control device 10. and.
  • the air conditioner 1 uses a working medium containing ethylene-based fluoroolefin as a refrigerant.
  • the control device 10 When the control device 10 detects that the pressure of the working medium in the high-pressure section including the compressor 100 and the condenser has increased to a threshold value or more in the heating operation state, the control device 10 controls the four-way valves 21 and 22 to return to the heating operation state. Switch from to cooling operation state. Thereby, the air conditioner 1 can realize a low GWP by using a working medium containing ethylene-based fluoroolefin. Further, the air conditioner 1 switches the air conditioner 1 from the heating operation state to the cooling operation when there is a possibility that a refrigerant disproportionation reaction has occurred, or when it is estimated that a disproportionation reaction has occurred. state to narrow the region HP through which high-pressure refrigerant flows.
  • the region HP where the pressure of the refrigerant rapidly increases due to the disproportionation reaction can be limited, and the influence of the disproportionation reaction on the refrigeration cycle can be suppressed.
  • the control of the control device 10 prevents or suppresses the influence of the disproportionation reaction from reaching the conditioned space. can.
  • the expansion mechanism includes an expansion valve 14 or expansion valves 12a, 12b located at the outlet of the condenser.
  • the air conditioner 1 includes a control device 10 that controls expansion valves 12a, 12b, and 14.
  • the control device 10 operates one of the expansion valves 12a, 12b, and 14 in the closing direction to a first opening degree when it is detected that the pressure of the working medium in the high-pressure part of the air conditioner 1 has increased to a threshold value or more. Then, when the pressure of the working medium in the high pressure section stops increasing, the expansion valve is operated in the closing direction to the second opening degree.
  • the second opening degree is, for example, a fully closed state.
  • the high pressure section includes, for example, a compressor 100 and a condenser.
  • the air conditioner 1 includes a relief valve 60 in a pipe 42 through which the compressor 100 discharges compressed refrigerant, which releases the pressure when the pressure in the pipe 42 is equal to or higher than a set pressure.
  • the compressor 100 includes a suction port 104 that sucks in a working medium, a compression mechanism 120 that compresses the working medium sucked from the suction port 104, and a compression mechanism that is connected to a different path from the suction port 104. and an injection section 125 that supplies a working medium to 120 .
  • the compressor 100 is an internal low-pressure type compressor in which a compression mechanism 120 is housed in a container 102 together with an electric motor 110, and the compression mechanism 120 sucks and compresses the working medium inside the container 102.
  • the condenser is the heat exchanger 13
  • the evaporator is the heat exchangers 11a and 11b.
  • the condenser is the heat exchanger 11a, 11b, and the evaporator is the heat exchanger 13.
  • the air conditioner 1 can realize a low GWP by using a working medium containing ethylene-based fluoroolefin.
  • a configuration in which the disproportionation reaction of the ethylene-based fluoroolefin is less likely to occur is realized. Therefore, disproportionation reactions can be suppressed when using a refrigerant with a low GWP.
  • the air conditioner 1 also includes a gas-liquid separator 15 disposed between the condenser and the evaporator, and a pipe 43 that sends a gaseous working medium from the gas-liquid separator 15 to the injection section 125.
  • the expansion mechanism constitutes a two-stage expansion process including an expansion valve 14 or expansion valves 12a, 12b disposed at the outlet of the condenser and operating as a first-stage pressure reduction mechanism, and a gas-liquid separator 15.
  • the region through which the high-pressure refrigerant flows in the air conditioner 1 can be limited to a narrow range, so it is possible to realize a configuration in which the disproportionation reaction of the refrigerant is difficult to propagate.
  • a temperature rise in the compression mechanism 120 can be suppressed and a configuration in which disproportionation reactions are less likely to occur can be realized.
  • the air conditioner 1 includes a pipe 41 that connects to the suction port 104 of the compressor 100 or a pipe 43 that allows a working medium to flow into a container 102 that accommodates the electric motor 110.
  • the air conditioner 1 includes a valve 16 that opens and closes the pipe 43 and a control device 10 that controls the valve 16.
  • the control device 10 controls the valve 16 to be opened when the temperature of the compression mechanism 120 satisfies preset conditions.
  • the temperature of the compression mechanism 120 satisfies preset conditions
  • the refrigerant is extracted from the gas-liquid separator 15 through the pipe 43, thereby reducing the pressure of the refrigerant in the gas-liquid separator 15, and separating the gas and liquid.
  • the refrigerant can be expanded in the vessel 15. Therefore, the gas-liquid separator 15 can act as an intercooler, and a two-stage expansion process can be configured in the expansion valve 14 and the gas-liquid separator 15.
  • the air conditioner 1 includes a heat exchanger 13 that is a heat source side heat exchanger, and heat exchangers 11a and 11b that are usage side heat exchangers.
  • the air conditioner 1 includes four-way valves 21 and 22 that switch between a heating operating state in which the heat exchangers 11a and 11b operate as condensers and a cooling operating state in which the heat exchanger 13 operates as a condenser.
  • the control device 10 detects that the pressure of the working medium in the high-pressure section including the compressor 100 and the condenser has increased to a threshold value or more in the heating operation state, the control device 10 controls the four-way valves 21 and 22 to return to the heating operation state. Switch from to cooling operation state.
  • the four-way valves 21 and 22 may be configured with a low differential pressure operated four-way valve or an electromagnetic on-off valve. In this case, when it is estimated that a disproportionation reaction has occurred in the high pressure section of the air conditioner 1 in the heating operating state, it is possible to quickly switch to the cooling operating state.
  • FIG. 5 is a diagram showing the configuration of the air conditioner 2 in the second embodiment.
  • the air conditioner 2 shown in FIG. 5 is an example to which the refrigeration circuit of the present invention is applied.
  • the air conditioner 2 has a compressor 200.
  • the compressor 200 is a two-stage compressor that includes a first compressor 100A and a second compressor 100B.
  • the first compressor 100A and the second compressor 100B do not include the injection section 125, but have the same configuration as the compressor 100 except for this point.
  • the first compressor 100A and the second compressor 100B have the same suction port 104 as the compressor 100, and the suction port 104 of the first compressor 100A corresponds to an example of the suction part of the entire compressor 200. do.
  • description of the configurations of the first compressor 100A and the second compressor 100B will be omitted.
  • the first compressor 100A is connected to the pipe 41, compresses the gaseous refrigerant supplied from the pipe 41, and discharges the compressed refrigerant to the connecting pipe 201.
  • the connecting pipe 201 is a pipe that connects the discharge side of the first compressor 100A and the suction side of the second compressor 100B.
  • the second compressor 100B sucks refrigerant from the connecting pipe 201, compresses it, and discharges the compressed high-pressure refrigerant to the pipe 42.
  • the first compressor 100A is a first-stage compressor and corresponds to an example of a first compression mechanism.
  • the second compressor 100B is a second stage compressor and corresponds to an example of a second compression mechanism.
  • a pipe 43 is connected to the connecting pipe 201 at the injection section 202.
  • the valve 16 is open, the refrigerant flows out from the gas-liquid separator 15 to the pipe 43, reducing the pressure of the refrigerant in the gas-liquid separator 15, and causing the refrigerant to flow into the gas-liquid separator 15.
  • the gas-liquid separator 15 functions as a type of heat exchanger. Due to this action, the pressure of the refrigerant is reduced in two stages in the expansion valve 14 and the gas-liquid separator 15 when the air conditioner 2 is in the cooling operation state. That is, the expansion valve 14 and the gas-liquid separator 15 constitute a two-stage expansion mechanism.
  • the region where the refrigerant becomes high temperature and high pressure in the cooling operation state is a high pressure section of the air conditioner 2 and includes any one of the compressor 200, the pipes 42 and 46, and the four-way valve 21. Since the expansion valve 14 and the gas-liquid separator 15 constitute a two-stage expansion mechanism, the region HP can be limited to a narrow range. Therefore, even if a refrigerant disproportionation reaction occurs, the range in which the refrigerant chain reaction propagates can be narrowed. Furthermore, by configuring a two-stage expansion process, the temperature of the compression mechanism 120 can be lowered, and the disproportionation reaction can be suppressed more effectively.
  • the injection unit 202 corresponds to an example of a refrigerant supply unit.
  • the four-way valve 21 and the four-way valve 22 are connected to the control device 20.
  • the four-way valve 21 and the four-way valve 22 operate under the control of the control device 20 to switch the air conditioner 2 between a cooling operation state and a heating operation state.
  • the compressor 200 may be a compound type compressor that accommodates a first compression mechanism in the first stage and a second compression mechanism in the second stage in one container. In this case, if the pipe 43 is connected to the suction side of the second compression mechanism, the same effect as the air conditioner 2 shown in FIG. 4 can be expected.
  • the refrigerant used in the air conditioner 2 is the working medium described as the refrigerant of the air conditioner 1 in the first embodiment. That is, the air conditioner 2 uses a working medium containing ethylene-based fluoroolefin as a refrigerant.
  • This working medium may include two or more refrigerant components.
  • the working medium used as a refrigerant in the air conditioner 2 may include a disproportionation inhibitor in addition to the refrigerant component.
  • the working medium may include a plurality of disproportionation inhibitors selected from saturated hydrocarbons and haloalkanes. Further, the working medium may contain one type of saturated hydrocarbon or may contain two or more types of saturated hydrocarbons. Further, the working medium may contain one type of haloalkane, or may contain two or more types of haloalkanes.
  • a preferred example of the working medium is a mixture containing 1,1,2-trifluoroethylene and n-propane, and containing unavoidable impurities.
  • This working medium may contain the second refrigerant component described above, or may contain other components.
  • the air conditioner 2 includes a control device 20.
  • the control device 20 includes a processor such as a microcontroller.
  • the control device 10 controls the air conditioner 2 by executing a program using a processor or by using programmed hardware functions.
  • the control device 20 is connected to a four-way valve 21 and a four-way valve 22.
  • the four-way valve 21 switches connections between the pipes 41 , 42 , 44 , and 46 under the control of the control device 20 .
  • the four-way valve 22 switches connections between the pipes 45 , 47 , 48 , and 49 under the control of the control device 20 .
  • the control device 20 operates the four-way valve 21 and the four-way valve 22 to switch between the cooling operation state and the heating operation state. That is, when the air conditioner 2 performs cooling operation, the control device 20 connects the piping 41 and the piping 44 and connects the piping 42 and the piping 46 using the four-way valve 21. Further, the control device 20 connects the piping 48 and the piping 45 and connects the piping 47 and the piping 49 using the four-way valve 22. When the air conditioner 2 performs heating operation, the control device 20 connects the piping 41 and the piping 46 and connects the piping 42 and the piping 44 using the four-way valve 21. Further, the control device 20 connects the piping 49 and the piping 45 and connects the piping 47 and the piping 48 using the four-way valve 22.
  • the expansion valves 12a, 12b, the expansion valve 14, and the valve 16 are connected to the control device 20.
  • the control device 20 fully opens the expansion valve 14 in the cooling operation state and adjusts the opening degrees of the expansion valves 12a and 12b.
  • the control device 20 fully opens the expansion valves 12a and 12b in the heating operation state, and adjusts the opening degree of the expansion valve 14.
  • the air conditioner 2 includes a temperature sensor (not shown) that detects the temperature of the electric motor of the first compressor 100A and/or the electric motor of the second compressor 100B, and a temperature sensor (not shown) that detects the temperature of the refrigerant discharged by the second compressor 100B. It may also include one or more of the following: a temperature sensor (not shown); These temperature sensors are connected to the control device 20.
  • the control device 20 detects either or both of the temperature of the electric motor and the temperature of the refrigerant discharged by the second compressor 100B by acquiring the detected value of the temperature sensor. Further, the control device 20 may calculate the pressure of the refrigerant discharged by the second compressor 100B based on the temperature of the refrigerant discharged by the second compressor 100B.
  • the air conditioner 2 may include a pressure sensor that detects the pressure of the refrigerant discharged by the second compressor 100B. Additionally, the air conditioner 2 may include a heat exchanger temperature sensor (not shown) that detects the temperatures of the heat exchangers 11a, 11b, and the heat exchanger 13. In this case, the control device 20 may calculate the pressure and temperature of the refrigerant discharged by the second compressor 100B based on the detected value of the heat exchanger temperature sensor. Good too.
  • the control device 20 executes control to open and close the valve 16.
  • the valve 16 is composed of an electric valve, a solenoid valve, or an expansion valve.
  • the control device 20 controls opening and closing of the valve 16 and adjusts the degree of opening of the valve 16.
  • the air conditioner 2 suppresses the disproportionation reaction of the refrigerant under the control of the control device 20 .
  • the control device 20 performs control to open the valve 16 when the temperature of the electric motor or the temperature of the refrigerant discharged from the second compressor 100B exceeds a threshold value. Further, the control device 20 suppresses the disproportionation reaction by operating the four-way valves 21, 22 and other valves.
  • the control device 20 executes the operation described with reference to FIG. 4, for example.
  • the control device 20 executes control to switch the air conditioner 2 from the heating operation state to the cooling operation state when the refrigerant pressure in the high pressure section of the air conditioner 2 increases to a threshold value or more.
  • the high pressure parts of the air conditioner 2 are, for example, the second compressor 100B, the piping 42, and the like.
  • control device 20 when the air conditioner 2 is in the cooling operation and when the air conditioner 2 is switched from the heating operation state to the cooling operation state, the control device 20 performs control to close the valve to be controlled to the first opening degree. I do. Then, when the pressure in the high pressure section stops increasing, the control device 20 performs control to close the valve that has been closed to the first opening degree to a fully closed state. After that, the control device 20 executes the notification. While performing these controls, the control device 20 may stop the compressor 200.
  • the air conditioner 2 of the second embodiment responds to the disproportionation reaction in the refrigeration cycle when the refrigerant disproportionation reaction occurs. The impact of this can be suppressed. That is, the air conditioner 2 includes a compressor 200, a heat exchanger 13 that is a heat source side heat exchanger, heat exchangers 11a and 11b that are usage side heat exchangers, and an expansion mechanism.
  • the air conditioner 2 includes four-way valves 21 and 22 that switch between a heating operating state in which the heat exchangers 11a and 11b operate as condensers and a cooling operating state in which the heat exchanger 13 operates as a condenser, and a control device 20.
  • the air conditioner 2 uses a working medium containing ethylene-based fluoroolefin as a refrigerant.
  • the control device 20 detects that the pressure of the working medium in the high-pressure section including the compressor 200 and the condenser has increased to a threshold value or more in the heating operation state, the control device 20 controls the four-way valves 21 and 22 to return to the heating operation state. Switch from to cooling operation state.
  • the air conditioner 2 achieves low GWP by using a working medium containing ethylene-based fluoroolefins.
  • the air conditioner 2 switches the air conditioner 2 from the heating operation state to the cooling operation when there is a possibility that a refrigerant disproportionation reaction has occurred, or when it is estimated that a disproportionation reaction has occurred. state to narrow the region HP through which high-pressure refrigerant flows. Thereby, the region where the pressure of the refrigerant rapidly increases due to the disproportionation reaction can be limited, and the influence of the disproportionation reaction can be suppressed.
  • the expansion mechanism of the air conditioner 2 includes an expansion valve 14 or expansion valves 12a, 12b arranged at the outlet of the condenser.
  • the control device 20 controls the expansion valves 12a, 12b, and 14.
  • the control device 20 operates one of the expansion valves 12a, 12b, and 14 in the closing direction to a first opening degree when it is detected that the pressure of the working medium in the high-pressure part of the air conditioner 2 has increased to a threshold value or more. Then, when the pressure of the working medium in the high pressure section stops increasing, the expansion valve is operated in the closing direction to the second opening degree.
  • the second opening degree is, for example, a fully closed state.
  • the high pressure section includes, for example, a compressor 100 and a condenser.
  • the air conditioner 2 includes a relief valve 60 in a pipe 42 through which the compressor 200 discharges compressed refrigerant, which releases the pressure when the pressure in the pipe 42 is equal to or higher than a set pressure.
  • the compressor 200 includes a suction port 104 that sucks a working medium, a first compressor 100A that compresses the working medium sucked from the suction port 104, and a first compressor 100A that compresses the working medium.
  • This is a two-stage compressor including a second compressor 100B that compresses the working medium.
  • the air conditioner 2 includes an injection section 202 that supplies a working medium between the first compressor 100A and the second compressor 100B. As a result, the air conditioner 2 can achieve low GWP by using a working medium containing ethylene-based fluoroolefins.
  • the injection unit 202 supplies refrigerant to the connecting pipe 201 between the first compressor 100A and the second compressor 100B, thereby lowering the temperature of the refrigerant discharged from the compressor 200. Achieve a configuration in which disproportionation reactions are less likely to occur. Therefore, disproportionation reactions can be suppressed when using a refrigerant with a low GWP. Furthermore, by using the two-stage compressor 200, the air conditioner 2 can suppress the compression ratio of each of the first compressor 100A and the second compressor 100B. Therefore, it is possible to reduce compression loss and the load on the electric motor of the compressor 200, and it can be expected to suppress a rise in the temperature of the electric motor.
  • control device 20 detects that the pressure of the working medium in the high pressure section has increased to a threshold value or more in the heating operation state of the air conditioner 2, the control device 20 controls the four-way valves 21 and 22 to change the heating operation state to the cooling state. Switch to operating state.
  • the control device 20 controls the four-way valves 21 and 22 to change the heating operation state to the cooling state. Switch to operating state.
  • the region through which the high-pressure refrigerant flows can be restricted by switching to the cooling operation state.
  • propagation of the disproportionation reaction can be suppressed.
  • high-pressure refrigerant does not flow to the heat exchangers 11a and 11b, which are the utilization side heat exchangers, so that the influence of the disproportionation reaction can be avoided from reaching the conditioned space.
  • the air conditioner 2 includes a pipe 43 that allows the working medium to flow into the injection section 202 from the gas-liquid separator 15 .
  • the air conditioner 2 includes a valve 16 that opens and closes the pipe 43 and a control device 20 that controls the valve 16.
  • the control device 20 controls the valve 16 to be opened when the temperature of the compressor 200 satisfies preset conditions.
  • the refrigerant is extracted from the gas-liquid separator 15 through the pipe 43, thereby reducing the pressure of the refrigerant in the gas-liquid separator 15, and separating the gas and liquid.
  • the refrigerant can be expanded in the vessel 15.
  • the gas-liquid separator 15 can act as an intercooler, and a two-stage expansion process can be configured in the expansion valve 14 and the gas-liquid separator 15. This makes it possible to eliminate a situation in which a disproportionation reaction is likely to occur in the compressor 200. Furthermore, when it is estimated that a disproportionation reaction has occurred in the compressor 200, the disproportionation reaction can be suppressed or stopped.
  • FIG. 6 is a diagram showing the configuration of an air conditioner 1A in the third embodiment.
  • An air conditioner 1A shown in FIG. 6 is an example to which the refrigeration circuit of the present invention is applied.
  • the air conditioner 1A has a configuration in which a pipe 55 and a valve 56 are added to the air conditioner 1 described with reference to FIGS. 1 to 4.
  • the configuration of each part except for the piping 55 and the valve 56 is the same as the configuration described in Embodiment 1, so the same reference numerals are given and the explanation will be omitted.
  • the pipe 55 is a refrigerant pipe that connects the pipe 48 and the pipe 41.
  • a valve 56 is provided in the pipe 55.
  • the valve 56 is composed of, for example, a solenoid valve, and opens and closes under the control of the control device 10.
  • the valve 56 may be a solenoid valve.
  • the control device 10 can adjust the opening degree of the valve 56 in addition to opening and closing the valve 56.
  • Piping 55 corresponds to an example of a motor cooling circuit
  • valve 56 corresponds to an example of a motor cooling valve.
  • refrigerant flows through the pipe 55 from the pipe 48 to the pipe 41.
  • the refrigerant flowing through the pipe 55 is a liquid refrigerant flowing from the gas-liquid separator 15 to the pipe 48 .
  • This refrigerant passes through the pipe 41 and reaches the suction port 104, and is supplied into the container 102.
  • liquid refrigerant is supplied to the electric motor 110 from the suction port 104.
  • This refrigerant cools the electric motor 110 in the process of being sucked into the compression mechanism 120 through the suction port 104.
  • Piping 55 may be directly connected to container 102 containing electric motor 110.
  • the temperature of the electric motor 110 can be lowered by supplying liquid refrigerant from the pipe 55 to the container 102.
  • the electric motor 110 can be cooled more effectively.
  • control device 10 executes the opening/closing control of the valve 16 described above and the control shown in FIG. 4.
  • control device 10 controls the valve 56 to be opened when the temperature of the compressor 100 satisfies a preset condition.
  • the preset condition is, for example, a temperature threshold of the compressor 100. Specifically, it is the temperature of the compressor 100 or the temperature of the refrigerant discharged from the compression mechanism 120.
  • the control device 10 opens the valve 56 when the temperature of the electric motor 110 or the temperature of the refrigerant discharged from the compression mechanism 120 exceeds a threshold value. By opening the valve 56, the control device 10 can supply liquid refrigerant to the electric motor 110 and lower the temperature of the electric motor 110. Thereby, the electric motor 110 can be cooled and the disproportionation reaction can be suppressed.
  • the air conditioner 1A controls the pipe 55 that allows liquid working medium to flow into the container 102 of the compressor 100 through the pipe 41, the valve 56 that opens and closes the pipe 55, and the valve 56.
  • a control device 10 is provided.
  • the control device 10 controls the valve 56 to be opened when the temperature of the compressor 100 satisfies preset conditions.
  • the electric motor 110 can be cooled by the liquid refrigerant.
  • the electric motor 110 reaches a high temperature and is in a state where a refrigerant disproportionation reaction is likely to occur, or when a refrigerant disproportionation reaction is estimated to occur, the electric motor 110 is cooled. can. Therefore, the disproportionation reaction of the refrigerant can be suppressed or stopped.
  • FIG. 7 is a diagram showing the configuration of an air conditioner 2A in Embodiment 4.
  • An air conditioner 2A shown in FIG. 7 is an example to which the refrigeration circuit of the present invention is applied.
  • the air conditioner 2A has a configuration in which the air conditioner 2 described with reference to FIG. 5 is provided with a pipe 57, a valve 58, and a valve 59.
  • the configuration of each part other than the piping 57, valve 58, and valve 59 is the same as the configuration described in the second embodiment, so the same reference numerals are given and the explanation will be omitted.
  • One end of the pipe 57 is connected to the pipe 48, and liquid refrigerant flows from the gas-liquid separator 15 to the pipe 57.
  • the pipe 57 branches into two branches at a branching portion 205 .
  • the pipe 57 is connected to the connecting pipe 201 at the connecting part 203 and to the pipe 41 at the connecting part 204.
  • a valve 58 is provided between the branch section 205 and the connection section 203, and a valve 59 is provided between the branch section 205 and the connection section 204.
  • the valves 58 and 59 are each formed of, for example, a solenoid valve, and are opened and closed under the control of the control device 20.
  • the valves 58 and 59 may be constituted by electromagnetic valves.
  • the control device 20 can adjust the opening degree of each of the valves 58 and 59 in addition to opening and closing the valves 58 and 59.
  • the pipe 57 corresponds to an example of a motor cooling circuit
  • the valves 58 and 59 correspond to an example of a motor cooling valve.
  • control device 20 executes the opening/closing control of the valve 16 described above and the control shown in FIG. 4, as described in the second embodiment.
  • control device 20 controls the valves 58 and 59 to be opened when the temperature of the compressor 200 satisfies preset conditions.
  • the preset condition is, for example, a temperature threshold of the compressor 200. Specifically, it is the temperature of the electric motor included in the first compressor 100A and/or the electric motor included in the second compressor 100B, or the temperature of the refrigerant discharged from the first compressor 100A and/or the second compressor 100B. .
  • the control device 20 opens the valve 58 when the temperature of the electric motor of the second compressor 100B or the temperature of the refrigerant discharged from the second compressor 100B exceeds a threshold value.
  • the control device 20 can cause the second compressor 100B to suck liquid refrigerant, thereby lowering the temperature of the electric motor of the second compressor 100B and the refrigerant discharged from the second compressor 100B.
  • the control device 20 opens the valve 59 when the temperature of the electric motor of the first compressor 100A or the temperature of the refrigerant discharged from the first compressor 100A exceeds a threshold value.
  • the control device 20 can cause the first compressor 100A to suck liquid refrigerant, thereby lowering the temperature of the electric motor of the first compressor 100A and the refrigerant discharged from the first compressor 100A.
  • the compressor 200 can be cooled to suppress or prevent the disproportionation reaction.
  • the air conditioner 2A of the fourth embodiment includes the pipe 57 that allows liquid working medium to flow into the compressor 200 through the pipe 43, the valves 58 and 59 that open and close the pipe 57, and the valves 58 and 59. and a control device 20 for controlling.
  • the control device 20 controls the valves 58 and 59 to be opened when the temperature of the compressor 200 satisfies preset conditions. Thereby, the compressor 200 can be cooled by allowing the refrigerant to flow into the compressor 200 through the pipe 43.
  • the electric motor of the first compressor 100A or the second compressor 100B reaches a high temperature and is in a state where a refrigerant disproportionation reaction is likely to occur, or it is estimated that a refrigerant disproportionation reaction is likely to occur. If this occurs, the motor can be cooled down. Therefore, the disproportionation reaction of the refrigerant can be suppressed or stopped.
  • FIG. 8 is a diagram showing the configuration of the air conditioner 3 in the fifth embodiment.
  • the air conditioner 3 shown in FIG. 8 is an example to which the refrigeration circuit of the present invention is applied.
  • the air conditioner 3 has a configuration common to a part of the air conditioner 1 described with reference to FIGS. 1 to 4. These common configurations are given the same reference numerals as those in Embodiment 1, and a description thereof will be omitted.
  • the present disclosure is applicable not only to the air conditioners 1, 1A, 2, and 2A of Embodiments 1 to 4 described above, but also to a refrigeration system that can switch between cooling operation and heating operation.
  • the air conditioner 3 corresponds to an example of this type of refrigeration device.
  • the air conditioner 3 includes heat exchangers 11a and 11b as usage side heat exchangers, expansion valves 12a and 12b provided in piping connected to the heat exchangers 11a and 11b, and a heat exchanger as a heat source side heat exchanger. 13 and an expansion valve 14 provided in a pipe 47 connected to the heat exchanger 13.
  • the air conditioner 3 also includes a compressor 100 and a four-way valve 21 that switches between the heat exchangers 11a, 11b or the heat exchanger 13 and connects to the piping 42 on the discharge side of the compressor 100.
  • the air conditioner 3 includes a control device 10A that controls the four-way valve 21.
  • the control device 10A like the control device 10, includes a processor such as a microcontroller.
  • the control device 10A controls the air conditioner 3 by executing a program using a processor or by using programmed hardware functions.
  • the control device 10A controls the four-way valve 21 to switch between a cooling operation state and a heating operation state.
  • control device 10A uses the four-way valve 21 to connect a pipe 42 through which the compressor 100 discharges high-pressure refrigerant to a pipe 46 connected to the heat exchanger 13, and a pipe 44 connected to the heat exchangers 11a and 11b. It is connected to the suction side piping 41 of the compressor 100. Thereby, the air conditioner 3 executes the cooling operation. During cooling operation, high-pressure refrigerant discharged from the compressor 100 is condensed in the heat exchanger 13 and sent to the heat exchangers 11a and 11b via the expansion valves 12a and 12b.
  • FIG. 8 shows the cooling operation state of the air conditioner 3.
  • the high pressure section HP includes, for example, a compressor 100, a pipe 42 through which a high pressure refrigerant flows, a four-way valve 21, and a heat exchanger 13.
  • the air conditioner 3 When the air conditioner 3 performs heating operation under the control of the control device 10A, the high-pressure refrigerant discharged by the compressor 100 is condensed in the heat exchangers 11a and 11b, and is transferred to the heat exchanger 13 via the expansion valve 14. Sent. This refrigerant is depressurized by the expansion valve 14, evaporated in the heat exchanger 13, and sucked into the compressor 100 through the pipe 41.
  • the region HP includes the compressor 100, the piping 42, the four-way valve 21, and the heat exchangers 11a and 11b.
  • the air conditioner 3 performs a cooling operation in which the heat exchanger 13 is operated as a condenser, and a cooling operation in which the heat exchanger 11a and 11b are operated as a condenser and the heat exchanger 13 is operated as an evaporator.
  • This is a refrigeration system that can switch between heating operation and heating operation using a four-way valve 21.
  • the air conditioner 3 may include one or more of a temperature sensor (not shown) that detects the temperature of the electric motor 110 and a temperature sensor (not shown) that detects the temperature of the refrigerant discharged by the compression mechanism 120. These temperature sensors are connected to the control device 10A.
  • the control device 10A detects either or both of the temperature of the electric motor 110 and the temperature of the refrigerant discharged by the compression mechanism 120 by acquiring the detected value of the temperature sensor. Further, the control device 10A may calculate the pressure of the refrigerant discharged by the compression mechanism 120 based on the temperature of the refrigerant discharged by the compression mechanism 120.
  • the air conditioner 3 may include a pressure sensor that detects the pressure of the refrigerant discharged by the compression mechanism 120.
  • the air conditioner 3 may include a heat exchanger temperature sensor (not shown) that detects the temperatures of the heat exchangers 11a, 11b and the heat exchanger 13.
  • the control device 10A may calculate the pressure and temperature of the refrigerant discharged by the compression mechanism 120 based on the detected value of the heat exchanger temperature sensor, or may be configured without the temperature sensor described above. .
  • the control device 10A executes the control shown in FIG. 4 similarly to the control device 10. That is, when the control device 10A detects that the pressure of the refrigerant in the high pressure portion HP has increased to a threshold value or more during the heating operation of the air conditioner 3, the control device 10A switches the air conditioner 3 to the cooling operation.
  • the air conditioner 3 includes the compressor 100, the heat exchanger 13 which is a heat source side heat exchanger, the heat exchangers 11a and 11b which are usage side heat exchangers, and an expansion mechanism.
  • the air conditioner 3 includes a four-way valve 21 that switches between a heating operation state in which the heat exchangers 11a and 11b operate as a condenser and a cooling operation state in which the heat exchanger 13 operates as a condenser, and a control device 10A. Equipped with The air conditioner 3 uses a working medium containing ethylene-based fluoroolefin as a refrigerant.
  • the control device 10A When the control device 10A detects that the pressure of the working medium in the high-pressure section including the compressor 100 and the condenser has increased to a threshold value or more in the heating operation state, the control device 10A controls the four-way valve 21 to switch from the heating operation state to the cooling state. Switch to operating state.
  • the air conditioner 3 can realize a low GWP by using a working medium containing ethylene-based fluoroolefin. Further, the air conditioner 3 switches the air conditioner 3 from the heating operation state to the cooling operation when there is a possibility that a refrigerant disproportionation reaction has occurred, or when it is estimated that a disproportionation reaction has occurred. state to narrow the region HP through which high-pressure refrigerant flows.
  • the region HP where the pressure of the refrigerant rapidly increases due to the disproportionation reaction can be limited, and the influence of the disproportionation reaction on the refrigeration cycle can be suppressed.
  • the control of the control device 10A prevents or suppresses the influence of the disproportionation reaction from reaching the conditioned space. can.
  • the expansion mechanism includes an expansion valve 14 or expansion valves 12a, 12b located at the outlet of the condenser.
  • the air conditioner 3 includes a control device 10A that controls the expansion valves 12a, 12b, and 14.
  • the control device 10A operates one of the expansion valves 12a, 12b, and 14 in the closing direction to a first opening degree when it is detected that the pressure of the working medium in the high-pressure part of the air conditioner 3 has increased to a threshold value or more. Then, when the pressure of the working medium in the high pressure section stops increasing, the expansion valve is operated in the closing direction to the second opening degree.
  • the second opening degree is, for example, a fully closed state.
  • the high pressure section includes, for example, a compressor 100 and a condenser.
  • the pipe 42 through which the compressor 100 discharges the compressed refrigerant is provided with a relief valve 60 that releases the pressure when the pressure in the pipe 42 is equal to or higher than the set pressure. You can. In this case, when the pressure in the pipe 42 suddenly increases due to the occurrence of the disproportionation reaction, the pressure in the pipe 42 can be released, and the influence of the disproportionation reaction can be reduced.
  • the relief valve 60 also called an overflow valve
  • the pressure release means may be a rupture disk that ruptures to release the pressure when the pressure in the pipe 42 exceeds a set pressure.
  • the compressor 100, the first compressor 100A, and the second compressor 100B in the embodiments described above are not limited to scroll compressors, but may be rotary compressors, or reciprocating compressors. It may be.
  • the air conditioner 1 may include a temperature sensor that detects the temperature of the heat exchangers 11a, 11b, and 13, and the same applies to the air conditioners 1A, 2, and 2A.
  • the air conditioners 1 and 1A may include a refrigerant temperature sensor that detects the temperature of the refrigerant discharged by the compressor 100.
  • the air conditioners 2 and 2A may include a refrigerant temperature sensor that detects the temperature of the refrigerant discharged by the compressor 200. These sensors may be connected to the control devices 10, 20 as appropriate so that the control devices 10, 20 can acquire the detected values of the sensors.
  • a compressor A heat source side heat exchanger, a user side heat exchanger, an expansion mechanism, a heating operation state in which the user side heat exchanger operates as a condenser, and a heating operation state in which the heat source side heat exchanger is operated as a condenser.
  • a switching valve that switches between a cooling operation state in which the condenser is operated and a control device; the control device uses a working medium containing ethylene-based fluoroolefin as a refrigerant;
  • the switching valve is controlled to switch from the heating operation state to the cooling operation state.
  • a refrigeration device characterized by the following.
  • the expansion mechanism includes an expansion valve disposed at the outlet of the condenser, and the control device causes the pressure of the working medium in a high-pressure section including the compressor and the condenser to rise to a threshold value or more.
  • the expansion valve is operated in the closing direction to a first opening degree, and then, when the pressure of the working medium in the high pressure section stops increasing, the expansion valve is operated to a second opening degree.
  • the refrigeration device according to technique 1 characterized in that the refrigeration device is operated in a closing direction.
  • the refrigeration system includes an air conditioner that cools and heats a space to be conditioned, a refrigeration system that includes a refrigerator or a freezer that has the function of switching between cooling and heating, and a refrigeration system that combines these. It can also be used for other purposes.
  • Air conditioning equipment (refrigeration equipment) 10, 10A, 20 Control device 11a, 11b Heat exchanger (user side heat exchanger) 12a, 12b expansion valve 13 heat exchanger (heat source side heat exchanger) 14 Expansion valve 15 Gas-liquid separator (refrigerant storage section) 16 Valve 20 Control device 21, 22 Four-way valve (switching valve) 41 Piping (suction piping) 42 Piping (discharge piping) 43 Piping (refrigerant piping) 44, 45, 46, 47, 48, 49 Piping 55, 57 Piping (motor cooling circuit) 56, 58, 59 valves (motor cooling valve) 60 Relief valve (pressure release means) 100, 200 compressor 102 container 103 crankshaft 104 suction port (suction part) 105 discharge pipe 107, 108 bearing 110 electric motor 111 stator 112 rotor 116 drive circuit 120 compression mechanism 125 injection section (refrigerant supply section) 100A 1st compressor (1st compression mechanism)

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Abstract

The present invention suppresses the effects caused in a refrigeration cycle when a disproportionation reaction of a refrigerant occurs.　A refrigeration device according to the present disclosure comprises: a compressor; a heat source side heat exchanger; a usage side heat exchanger; an expansion mechanism; a switching valve that switches between a heating operation state for operating the usage side heat exchanger as a condenser and a cooling operation state for operating the heat source side heat exchanger as a condenser; and a control device, wherein a working medium containing an ethylene-based fluoroolefin is used as the refrigerant, and when it is detected that, in the heating operation state, the pressure of the working medium in a high pressure part that includes the compressor and the condenser has risen to a threshold value or higher, the control device controls the switching valve to switch from the heating operation state to the cooling operation state.

Description

冷凍装置Refrigeration equipment
　本発明は、冷凍装置に関する。 The present invention relates to a refrigeration device.
　特許文献１は、低ＧＷＰ（Ｇｌｏｂａｌ　Ｗａｒｍｉｎｇ　Ｐｏｔｅｎｔｉａｌ）を用いる冷凍機を開示する。特許文献１の冷凍機は、トランス－１，２－ジフルオロエチレン（ＨＦＯ－１１３２（Ｅ））、２，３，３，３－テトラフルオロ－１－プロペン（Ｒ１２３４ｙｆ）、トリフルオロエチレン（ＨＦＯ－１１２３）等を含む冷媒を利用する。 Patent Document 1 discloses a refrigerator using low GWP (Global Warming Potential). The refrigerator of Patent Document 1 uses trans-1,2-difluoroethylene (HFO-1132(E)), 2,3,3,3-tetrafluoro-1-propene (R1234yf), and trifluoroethylene (HFO-1123). ) etc.
特開２０２２－５９６１９号公報JP 2022-59619 Publication
　本開示は、冷媒の不均化反応が発生した場合に、冷凍サイクルにおける不均化反応の影響を抑えることが可能な冷凍装置を提供する。 The present disclosure provides a refrigeration system that can suppress the influence of the disproportionation reaction in a refrigeration cycle when the disproportionation reaction of the refrigerant occurs.
　この明細書には、２０２２年４月２８日に出願された日本国特許出願・特願２０２２－０７４９７３の全ての内容が含まれる。
　本開示における冷凍装置は、圧縮機と、熱源側熱交換器と、利用側熱交換器と、膨張機構と、前記利用側熱交換器を凝縮器として動作させる暖房運転状態と、前記熱源側熱交換器を凝縮器として動作させる冷房運転状態と、を切り替える切替弁と、制御装置と、を備え、冷媒として、エチレン系フルオロオレフィンを含む作動媒体を使用し、前記制御装置は、前記暖房運転状態で前記圧縮機と前記凝縮器とを含む高圧部における前記作動媒体の圧力が閾値以上まで上昇したことを検出した場合に、前記切替弁を制御して前記暖房運転状態から前記冷房運転状態への切り替えを行う。 This specification includes all contents of Japanese patent application/Japanese Patent Application No. 2022-074973 filed on April 28, 2022.
The refrigeration system according to the present disclosure includes a compressor, a heat source side heat exchanger, a user side heat exchanger, an expansion mechanism, a heating operation state in which the user side heat exchanger operates as a condenser, and a heating operation state in which the user side heat exchanger operates as a condenser. a switching valve that switches between a cooling operating state in which the exchanger operates as a condenser; and a control device; the control device uses a working medium containing ethylene-based fluoroolefin as a refrigerant; If it is detected that the pressure of the working medium in the high pressure section including the compressor and the condenser has increased to a threshold value or more, the switching valve is controlled to switch from the heating operation state to the cooling operation state. Make the switch.
　本開示における冷凍装置は、エチレン系フルオロオレフィンを含む作動媒体を冷媒として利用することにより低ＧＷＰ化を実現し、冷媒の不均化反応が発生した場合の影響を抑えることができる。 The refrigeration device according to the present disclosure achieves low GWP by using a working medium containing ethylene-based fluoroolefins as a refrigerant, and can suppress the effects when a refrigerant disproportionation reaction occurs.
図１は、本発明の実施の形態１に係る空気調和装置の構成を示す図FIG. 1 is a diagram showing the configuration of an air conditioner according to Embodiment 1 of the present invention. 図２は、圧縮機の構成を示す図Figure 2 is a diagram showing the configuration of the compressor. 図３は、本発明の実施の形態１に係る空気調和装置の構成を示す図FIG. 3 is a diagram showing the configuration of an air conditioner according to Embodiment 1 of the present invention. 図４は、実施の形態１に係る空気調和装置の動作を示すフローチャートFIG. 4 is a flowchart showing the operation of the air conditioner according to the first embodiment. 図５は、本発明の実施の形態２に係る空気調和装置の構成を示す図FIG. 5 is a diagram showing the configuration of an air conditioner according to Embodiment 2 of the present invention. 図６は、本発明の実施の形態３に係る空気調和装置の構成を示す図FIG. 6 is a diagram showing the configuration of an air conditioner according to Embodiment 3 of the present invention. 図７は、本発明の実施の形態４に係る空気調和装置の構成を示す図FIG. 7 is a diagram showing the configuration of an air conditioner according to Embodiment 4 of the present invention. 図８は、本発明の実施の形態５に係る空気調和装置の構成を示す図FIG. 8 is a diagram showing the configuration of an air conditioner according to Embodiment 5 of the present invention.
　（本開示の基礎となった知見等）
　発明者らが本開示に想到するに至った当時、冷凍装置において、地球温暖化係数（ＧＷＰ）を低減した冷媒の利用が提案されていた。例えば、分子内に炭素－炭素不飽和結合を有するフルオロオレフィン類は、冷却能力が高く、ＧＷＰが低いという利点がある。しかしながら、ＧＷＰの低い冷媒は易分解性であるため、特定の条件下において、不均化と呼ばれる自己分解反応を起こす可能性がある。冷媒の不均化が発生すると、冷媒回路における圧力が急激に上昇し、機器の破損を招く可能性がある。そのため、このような不均化反応が冷凍サイクルにおいて発生した場合に、その影響を抑える必要があると言う課題を発明者らは発見し、その課題を解決するために、本開示の主題を構成するに至った。
　そこで本開示は、冷媒の不均化反応が発生した場合に、冷凍サイクルにおける不均化反応の影響を抑えることが可能な冷凍装置を提供する。
　以下、図面を参照しながら、実施の形態を詳細に説明する。但し、必要以上に詳細な説明は省略する場合がある。例えば、既によく知られた事項の詳細説明、または、実質的に同一の構成に対する重複説明を省略する場合がある。これは、以下の説明が必要以上に冗長になるのを避け、当業者の理解を容易にするためである。
　なお、添付図面および以下の説明は、当業者が本開示を十分に理解するために提供されるのであって、これらにより特許請求の範囲に記載の主題を限定することを意図していない。 (Findings, etc. that formed the basis of this disclosure)
At the time the inventors came up with the present disclosure, the use of refrigerants with reduced global warming potential (GWP) was proposed in refrigeration equipment. For example, fluoroolefins having carbon-carbon unsaturated bonds in their molecules have the advantage of high cooling ability and low GWP. However, since refrigerants with low GWP are easily decomposed, under certain conditions, there is a possibility that a self-decomposition reaction called disproportionation will occur. When refrigerant disproportionation occurs, the pressure in the refrigerant circuit increases rapidly, potentially causing equipment damage. Therefore, when such a disproportionation reaction occurs in a refrigeration cycle, the inventors discovered the problem that it is necessary to suppress its influence, and in order to solve this problem, the subject of the present disclosure is constituted. I ended up doing it.
Therefore, the present disclosure provides a refrigeration system that can suppress the influence of the disproportionation reaction in a refrigeration cycle when the disproportionation reaction of the refrigerant occurs.
Hereinafter, embodiments will be described in detail with reference to the drawings. However, more detailed explanation than necessary may be omitted. For example, detailed explanations of well-known matters or redundant explanations of substantially the same configurations may be omitted. This is to avoid making the following description unnecessarily redundant and to facilitate understanding by those skilled in the art.
The accompanying drawings and the following description are provided to enable those skilled in the art to fully understand the present disclosure, and are not intended to limit the subject matter recited in the claims.
　（実施の形態１）
　以下、図１～図４を用いて、実施の形態１を説明する。
　［１－１．空気調和装置の構成］
　図１及び図３は、実施の形態１における空気調和装置１の構成を示す図であり、図２は、空気調和装置１が備える圧縮機１００の構成を示す図である。
　図１及び図３に示す空気調和装置１は、本発明の冷凍回路を適用した一例である。図１は、空気調和装置１の冷房運転状態を示し、図３は空気調和装置１の暖房運転状態を示す。 (Embodiment 1)
Embodiment 1 will be described below using FIGS. 1 to 4.
[1-1. Configuration of air conditioner]
1 and 3 are diagrams showing the configuration of air conditioner 1 in Embodiment 1, and FIG. 2 is a diagram showing the configuration of compressor 100 included in air conditioner 1.
The air conditioner 1 shown in FIGS. 1 and 3 is an example to which the refrigeration circuit of the present invention is applied. FIG. 1 shows a cooling operation state of the air conditioner 1, and FIG. 3 shows a heating operation state of the air conditioner 1.
　空気調和装置１は、圧縮機１００、熱交換器１１ａ、１１ｂ、膨張弁１２ａ、１２ｂ、熱交換器１３、膨張弁１４、気液分離器１５、弁１６、四方弁２１、２２、及び、これらを接続する冷媒配管を備える。また、空気調和装置１は、膨張弁１２ａ、１２ｂ、膨張弁１４、弁１６、及び、四方弁２１、２２を制御する制御装置１０を備える。四方弁２１、２２は切替弁の一例に対応する。 The air conditioner 1 includes a compressor 100, heat exchangers 11a and 11b, expansion valves 12a and 12b, a heat exchanger 13, an expansion valve 14, a gas-liquid separator 15, a valve 16, four- way valves 21 and 22, and Equipped with refrigerant piping to connect. The air conditioner 1 also includes a control device 10 that controls the expansion valves 12a, 12b, the expansion valve 14, the valve 16, and the four- way valves 21, 22. The four- way valves 21 and 22 correspond to an example of a switching valve.
　圧縮機１００は、図２を参照して後述するように、吸込口１０４、吐出管１０５、及び、インジェクション部１２５を備える。圧縮機１００は、吸込口１０４から冷媒を吸い込んで圧縮し、高圧の冷媒を吐出管１０５から吐出する。 The compressor 100 includes a suction port 104, a discharge pipe 105, and an injection section 125, as will be described later with reference to FIG. The compressor 100 sucks and compresses refrigerant through a suction port 104, and discharges high-pressure refrigerant through a discharge pipe 105.
　熱交換器１１ａ、１１ｂは、室内ユニットに設置され、被調和空間の冷房および暖房を行う利用側熱交換器である。熱交換器１１ａと熱交換器１１ｂとは並列に接続される。熱交換器１３は、室外ユニットに設置される熱源側熱交換器である。熱交換器１１ａ、熱交換器１１ｂ、及び、熱交換器１３のそれぞれにはファンが設けられる。 The heat exchangers 11a and 11b are user-side heat exchangers that are installed in the indoor unit and perform cooling and heating of the conditioned space. Heat exchanger 11a and heat exchanger 11b are connected in parallel. The heat exchanger 13 is a heat source side heat exchanger installed in the outdoor unit. Each of heat exchanger 11a, heat exchanger 11b, and heat exchanger 13 is provided with a fan.
　四方弁２１には、圧縮機１００の吸込口１０４に繋がる配管４１と、吐出管１０５に繋がる配管４２と、熱交換器１１ａ、１１ｂに繋がる配管４４と、熱交換器１３に繋がる４６とが接続される。配管４１は吸入配管の一例に対応する。配管４２は吐出配管の一例に対応する。四方弁２１は、制御装置１０の制御によって、配管４１、４２、４４、４６の接続を切り替える。 A pipe 41 connected to the suction port 104 of the compressor 100, a pipe 42 connected to the discharge pipe 105, a pipe 44 connected to the heat exchangers 11a and 11b, and a pipe 46 connected to the heat exchanger 13 are connected to the four-way valve 21. be done. Piping 41 corresponds to an example of suction piping. The pipe 42 corresponds to an example of a discharge pipe. The four-way valve 21 switches connections between the pipes 41 , 42 , 44 , and 46 under the control of the control device 10 .
　四方弁２２には、熱交換器１１ａ、１１ｂに繋がる配管４５と、熱交換器１３に繋がる配管４７と、気液分離器１５に繋がる配管４８及び配管４９と、が接続される。配管４９は気液分離器１５に冷媒を流入させる配管であり、配管４８は気液分離器１５から冷媒が流出する配管である。気液分離器１５は、配管４８から流入する冷媒を貯留し、液体の冷媒と気体の冷媒とを分けて取出可能なタンクである。気液分離器１５は、冷媒貯留部の一例に対応する。四方弁２２は、制御装置１０の制御によって、配管４５、４７、４８、４９の接続を切り替える。 A pipe 45 connected to the heat exchangers 11a and 11b, a pipe 47 connected to the heat exchanger 13, and a pipe 48 and a pipe 49 connected to the gas-liquid separator 15 are connected to the four-way valve 22. Piping 49 is a piping that allows the refrigerant to flow into the gas-liquid separator 15, and piping 48 is a piping that allows the refrigerant to flow out from the gas-liquid separator 15. The gas-liquid separator 15 is a tank that stores the refrigerant flowing in from the pipe 48 and can separate and take out the liquid refrigerant and the gas refrigerant. The gas-liquid separator 15 corresponds to an example of a refrigerant storage section. The four-way valve 22 switches connections between the pipes 45 , 47 , 48 , and 49 under the control of the control device 10 .
　図１には、冷房運転状態における冷媒の流れを、符号ＲＣを付した矢印で示す。図２には、暖房運転状態における冷媒の流れを、符号ＲＨを付した矢印で示す。
　また、図１～図３、及び後述する図５～図７には、冷房運転状態と暖房運転状態とで共通する冷媒の流れを、符号Ｒを付した矢印で示す。 In FIG. 1, the flow of refrigerant in the cooling operation state is shown by arrows labeled RC. In FIG. 2, the flow of the refrigerant in the heating operation state is shown by arrows labeled RH.
Further, in FIGS. 1 to 3 and FIGS. 5 to 7, which will be described later, the flow of the refrigerant that is common between the cooling operation state and the heating operation state is shown by an arrow with a symbol R.
　図１に示す冷房運転状態において、四方弁２１は、配管４２と配管４６とを接続し、配管４４と配管４１とを接続する。四方弁２２は、配管４７と配管４９とを接続し、配管４８と配管４５とを接続する。 In the cooling operation state shown in FIG. 1, the four-way valve 21 connects the pipe 42 and the pipe 46, and connects the pipe 44 and the pipe 41. The four-way valve 22 connects the piping 47 and the piping 49, and connects the piping 48 and the piping 45.
　空気調和装置１の冷房運転状態では、圧縮機１００から吐出管１０５に吐出された冷媒が、配管４２及び四方弁２１を経由して熱交換器１３に流入し、熱交換器１３で凝縮される。つまり、冷房運転状態で熱交換器１３は凝縮器として機能する。熱交換器１３で凝縮された冷媒は、配管４７、四方弁２２、及び配管４９を通って気液分離器１５に流入する。 In the cooling operation state of the air conditioner 1, the refrigerant discharged from the compressor 100 into the discharge pipe 105 flows into the heat exchanger 13 via the pipe 42 and the four-way valve 21, and is condensed in the heat exchanger 13. . That is, the heat exchanger 13 functions as a condenser in the cooling operation state. The refrigerant condensed in the heat exchanger 13 flows into the gas-liquid separator 15 through the pipe 47, the four-way valve 22, and the pipe 49.
　さらに、冷房運転状態では、気液分離器１５から配管４８及び四方弁２２を通って液体の冷媒が膨張弁１２ａ、１２ｂに供給される。膨張弁１２ａは冷媒を減圧して熱交換器１１ａに供給し、膨張弁１２ｂは冷媒を減圧して熱交換器１１ｂに供給する。熱交換器１１ａ、１１ｂは、冷房運転状態で蒸発器として機能し、膨張弁１２ａ、１２ｂで減圧された冷媒を気化させる。熱交換器１１ａ、１１ｂで気化した冷媒は、配管４４、四方弁２１及び配管４１を通じて圧縮機１００に送られる。 Further, in the cooling operation state, liquid refrigerant is supplied from the gas-liquid separator 15 to the expansion valves 12a and 12b through the pipe 48 and the four-way valve 22. The expansion valve 12a reduces the pressure of the refrigerant and supplies it to the heat exchanger 11a, and the expansion valve 12b reduces the pressure of the refrigerant and supplies it to the heat exchanger 11b. The heat exchangers 11a and 11b function as evaporators during cooling operation, and vaporize the refrigerant whose pressure has been reduced by the expansion valves 12a and 12b. The refrigerant vaporized in the heat exchangers 11a and 11b is sent to the compressor 100 through the pipe 44, the four-way valve 21, and the pipe 41.
　一方、暖房運転状態で、四方弁２１は、配管４２と配管４４とを接続し、配管４６と配管４１とを接続する。四方弁２２は、配管４７と配管４８とを接続し、配管４９と配管４５とを接続する。 On the other hand, in the heating operation state, the four-way valve 21 connects the piping 42 and the piping 44, and connects the piping 46 and the piping 41. The four-way valve 22 connects the piping 47 and the piping 48 and connects the piping 49 and the piping 45.
　空気調和装置１の暖房運転状態では、吐出管１０５から吐出された冷媒が配管４２及び四方弁２１を通って熱交換器１１ａ、１１ｂに流入し、熱交換器１１ａ、１１ｂで凝縮される。つまり、暖房運転状態で熱交換器１１ａ、１１ｂは凝縮器として機能する。熱交換器１１ａ、１１ｂで凝縮された冷媒は配管４５、四方弁２２、及び配管４９を通って気液分離器１５に流入する。 In the heating operation state of the air conditioner 1, the refrigerant discharged from the discharge pipe 105 flows into the heat exchangers 11a and 11b through the pipe 42 and the four-way valve 21, and is condensed in the heat exchangers 11a and 11b. That is, in the heating operation state, the heat exchangers 11a and 11b function as condensers. The refrigerant condensed in the heat exchangers 11a and 11b flows into the gas-liquid separator 15 through the pipe 45, the four-way valve 22, and the pipe 49.
　さらに、暖房運転状態では、気液分離器１５から配管４８及び四方弁２２を通じて液体の冷媒が膨張弁１４に供給される。膨張弁１４は冷媒を減圧して熱交換器１３に供給する。熱交換器１３は、暖房運転状態で蒸発器として機能し、膨張弁１４で減圧された冷媒を気化させる。熱交換器１３で気化した冷媒は配管４６、四方弁２１及び配管４１を通じて吸込口１０４に吸い込まれる。 Further, in the heating operation state, liquid refrigerant is supplied from the gas-liquid separator 15 to the expansion valve 14 through the pipe 48 and the four-way valve 22. The expansion valve 14 reduces the pressure of the refrigerant and supplies it to the heat exchanger 13 . The heat exchanger 13 functions as an evaporator in the heating operation state, and vaporizes the refrigerant whose pressure has been reduced by the expansion valve 14. The refrigerant vaporized in the heat exchanger 13 is sucked into the suction port 104 through the pipe 46, the four-way valve 21, and the pipe 41.
　制御装置１０は、マイクロコントローラ等のプロセッサを備える。制御装置１０は、プロセッサによりプログラムを実行することにより、或いは、プログラムされたハードウェアの機能により空気調和装置１を制御する。 The control device 10 includes a processor such as a microcontroller. The control device 10 controls the air conditioner 1 by executing a program using a processor or by using programmed hardware functions.
　制御装置１０は、四方弁２１及び四方弁２２を制御して、冷房運転状態と暖房運転状態とを切り替える。また、制御装置１０は、冷房運転状態において膨張弁１２ａ、１２ｂの開度を調整する。制御装置１０は、暖房運転状態において膨張弁１４の開度を調整する。 The control device 10 controls the four-way valve 21 and the four-way valve 22 to switch between the cooling operation state and the heating operation state. Further, the control device 10 adjusts the opening degrees of the expansion valves 12a and 12b in the cooling operation state. The control device 10 adjusts the opening degree of the expansion valve 14 in the heating operation state.
　制御装置１０は、配管４３に設けられる弁１６を開閉させる制御を実行する。弁１６は、電動弁、電磁弁或いは膨張弁により構成される。弁１６が電動弁または膨張弁である場合、制御装置１０は、弁１６の開閉の制御、及び、弁１６の開度の調整を行う。 The control device 10 executes control to open and close the valve 16 provided in the pipe 43. The valve 16 is composed of an electric valve, a solenoid valve, or an expansion valve. When the valve 16 is an electric valve or an expansion valve, the control device 10 controls opening and closing of the valve 16 and adjusts the opening degree of the valve 16.
　空気調和装置１は、電動機１１０の温度を検出する不図示の温度センサ、及び、圧縮機構１２０が吐出する冷媒の温度を検出する不図示の温度センサのいずれか１以上を備えてもよい。これらの温度センサは制御装置１０に接続される。制御装置１０は、温度センサの検出値を取得することにより、電動機１１０の温度、及び、圧縮機構１２０が吐出する冷媒の温度のいずれか、或いは両方を検出する。また、制御装置１０は、圧縮機構１２０が吐出する冷媒の温度に基づいて、圧縮機構１２０が吐出する冷媒の圧力を算出してもよい。 The air conditioner 1 may include one or more of a temperature sensor (not shown) that detects the temperature of the electric motor 110 and a temperature sensor (not shown) that detects the temperature of the refrigerant discharged by the compression mechanism 120. These temperature sensors are connected to the control device 10. The control device 10 detects either or both of the temperature of the electric motor 110 and the temperature of the refrigerant discharged by the compression mechanism 120 by acquiring the detection value of the temperature sensor. Further, the control device 10 may calculate the pressure of the refrigerant discharged by the compression mechanism 120 based on the temperature of the refrigerant discharged by the compression mechanism 120.
　空気調和装置１は、圧縮機構１２０が吐出する冷媒の圧力を検出する圧力センサを備えてもよい。また、空気調和装置１は、熱交換器１１ａ、１１ｂ、及び、熱交換器１３の温度を検出する不図示の熱交換器温度センサを備えてもよい。この場合、制御装置１０は、熱交換器温度センサの検出値に基づいて、圧縮機構１２０が吐出する冷媒の圧力や温度を算出してもよく、上述した温度センサを備えていない構成としてもよい。 The air conditioner 1 may include a pressure sensor that detects the pressure of the refrigerant discharged by the compression mechanism 120. Furthermore, the air conditioner 1 may include a heat exchanger temperature sensor (not shown) that detects the temperatures of the heat exchangers 11a, 11b, and the heat exchanger 13. In this case, the control device 10 may calculate the pressure and temperature of the refrigerant discharged by the compression mechanism 120 based on the detected value of the heat exchanger temperature sensor, or may be configured without the above-mentioned temperature sensor. .
　配管４３は、気液分離器１５から気体の冷媒を圧縮機１００に供給する。配管４３は、気液分離器１５に貯留された冷媒を、吸込口１０４に繋がる配管４８とは別の経路で圧縮機１００に供給するので、バイパス配管と呼ぶことができる。配管４３は、圧縮機１００のインジェクション部１２５に接続される。配管４３によって冷媒がインジェクション部１２５に供給されることにより、圧縮機１００が冷却される。インジェクション部１２５は、冷媒供給部の一例に対応する。配管４３は冷媒配管の一例に対応する。 The pipe 43 supplies gaseous refrigerant from the gas-liquid separator 15 to the compressor 100. Since the pipe 43 supplies the refrigerant stored in the gas-liquid separator 15 to the compressor 100 through a route different from the pipe 48 connected to the suction port 104, it can be called a bypass pipe. Piping 43 is connected to injection section 125 of compressor 100. The compressor 100 is cooled by supplying refrigerant to the injection section 125 through the pipe 43. The injection unit 125 corresponds to an example of a refrigerant supply unit. The pipe 43 corresponds to an example of a refrigerant pipe.
　吐出管１０５に繋がる配管４２には、リリーフバルブ６０が設けられる。図１及び図３の例では、配管４２にリリーフバルブ６０が設けられる。リリーフバルブ６０は、冷媒の圧力が、予め設定された設定圧以上となった場合に自動的に開放する弁であり、圧縮機構１２０の圧縮室および吐出管１０５の圧力を低下させる。リリーフバルブ６０は、圧力解放手段の一例に対応する。リリーフバルブ６０は、吐出管１０５に設けられてもよい。 A relief valve 60 is provided in the pipe 42 connected to the discharge pipe 105. In the example of FIGS. 1 and 3, a relief valve 60 is provided in the piping 42. The relief valve 60 is a valve that automatically opens when the pressure of the refrigerant exceeds a preset pressure, and reduces the pressure in the compression chamber of the compression mechanism 120 and the discharge pipe 105. The relief valve 60 corresponds to an example of pressure release means. The relief valve 60 may be provided in the discharge pipe 105.
　［１－２．圧縮機の構成］
　図２に示すように、圧縮機１００は、容器１０２を有する。容器１０２は、冷媒を圧縮する圧縮機構１２０と、圧縮機構１２０を駆動する電動機１１０とを収容する。
　電動機１１０は、固定子１１１と、回転子１１２とを有する。回転子１１２にはクランク軸１０３が連結され、クランク軸１０３は軸受１０７、１０８によって回転自在に支持される。これにより、回転子１１２はクランク軸１０３とともに回転自在に保持される。 [1-2. Compressor configuration]
As shown in FIG. 2, compressor 100 has a container 102. As shown in FIG. The container 102 houses a compression mechanism 120 that compresses refrigerant and an electric motor 110 that drives the compression mechanism 120.
Electric motor 110 has a stator 111 and a rotor 112. A crankshaft 103 is connected to the rotor 112, and the crankshaft 103 is rotatably supported by bearings 107 and 108. Thereby, the rotor 112 is rotatably held together with the crankshaft 103.
　圧縮機１００において、電動機１１０は、例えば容器１０２の内部空間の下部部に位置し、電動機１１０の上方に圧縮機構１２０が位置する。容器１０２の底部には不図示の冷凍機油が貯留される。 In the compressor 100, the electric motor 110 is located, for example, in the lower part of the internal space of the container 102, and the compression mechanism 120 is located above the electric motor 110. Refrigerating machine oil (not shown) is stored at the bottom of the container 102 .
　電動機１１０は、いわゆる集中巻のモーターである。固定子１１１は、三相の固定子巻線を有するティースと、ティースをつなぐヨークとを有し、固定子１１１の固定子巻線は不図示のリード線によって、インバータ式の駆動回路１１６に接続される。回転子１１２は、永久磁石を有し、固定子１１１に流れる電流により発生する回転磁界によって、クランク軸１０３とともに回転する。駆動回路１１６は、電動機１１０の制御に従って固定子１１１に駆動電流を出力する。 The electric motor 110 is a so-called concentrated winding motor. The stator 111 has teeth having three-phase stator windings and a yoke that connects the teeth, and the stator windings of the stator 111 are connected to an inverter-type drive circuit 116 by lead wires (not shown). be done. The rotor 112 has a permanent magnet and rotates together with the crankshaft 103 by a rotating magnetic field generated by a current flowing through the stator 111. Drive circuit 116 outputs a drive current to stator 111 under control of electric motor 110.
　圧縮機構１２０は、例えば、スクロール式の圧縮機構である。圧縮機構１２０は、固定スクロール１２１と、固定スクロール１２１に組み合わされた揺動スクロール１２２とを有し、固定スクロール１２１と揺動スクロール１２２との間の空間が圧縮室として機能する。圧縮機構１２０は、クランク軸１０３とともに揺動スクロール１２２が回転することによって、冷媒を圧縮する。圧縮機構１２０により圧縮された冷媒は、吐出管１０５を通じて排出される。 The compression mechanism 120 is, for example, a scroll type compression mechanism. The compression mechanism 120 includes a fixed scroll 121 and an oscillating scroll 122 combined with the fixed scroll 121, and a space between the fixed scroll 121 and the oscillating scroll 122 functions as a compression chamber. The compression mechanism 120 compresses the refrigerant by rotating the swinging scroll 122 together with the crankshaft 103. The refrigerant compressed by the compression mechanism 120 is discharged through the discharge pipe 105.
　圧縮機１００は、吸込口１０４を通じて容器１０２の内部に流入する冷媒を圧縮機構１２０が吸入して圧縮する、いわゆる内部低圧型の圧縮機である。吸込口１０４から容器１０２に流入した冷媒は、矢印ＲＩで示すように、電動機１１０の固定子１１１と回転子１１２との間の空間であるエアギャップを通って圧縮機構１２０に吸引される。エアギャップを流れる冷媒によって、電動機１１０が冷却される。 The compressor 100 is a so-called internal low pressure type compressor in which a compression mechanism 120 sucks and compresses the refrigerant flowing into the container 102 through the suction port 104. The refrigerant flowing into the container 102 from the suction port 104 is sucked into the compression mechanism 120 through an air gap, which is a space between the stator 111 and the rotor 112 of the electric motor 110, as shown by arrow RI. The electric motor 110 is cooled by the refrigerant flowing through the air gap.
　インジェクション部１２５は、容器１０２の内外を連通する管であり、インジェクション部１２５の先端は圧縮機構１２０の圧縮室に開口する。インジェクション部１２５には、上述したように配管４３が接続され、配管４３を通じて気体の冷媒が供給される。 The injection part 125 is a tube that communicates between the inside and outside of the container 102, and the tip of the injection part 125 opens into the compression chamber of the compression mechanism 120. The piping 43 is connected to the injection section 125 as described above, and gaseous refrigerant is supplied through the piping 43.
　配管４３からインジェクション部１２５から圧縮室に冷媒が流入することにより、気液分離器１５の冷媒が圧縮機構１２０に吸引される。これにより、気液分離器１５からガス状の冷媒を抜き取られるので、気液分離器１５の冷媒の圧力を低下させ、気液分離器１５で冷媒を膨張させる作用が生じる。
　インジェクション部１２５は、容器１０２の内部において、圧縮機構１２０が容器１０２の内部の冷媒を吸い込む吸い込み口、または、その近傍に開口してもよい。この場合も、気液分離器１５からガス状の冷媒を抜き取る作用を生じさせることができる。 When the refrigerant flows into the compression chamber from the injection section 125 through the pipe 43, the refrigerant in the gas-liquid separator 15 is sucked into the compression mechanism 120. As a result, the gaseous refrigerant is extracted from the gas-liquid separator 15, thereby reducing the pressure of the refrigerant in the gas-liquid separator 15 and causing the refrigerant to expand in the gas-liquid separator 15.
The injection part 125 may be opened inside the container 102 at or near a suction port through which the compression mechanism 120 sucks the refrigerant inside the container 102 . In this case as well, the effect of extracting the gaseous refrigerant from the gas-liquid separator 15 can be produced.
　［１－３．冷媒］
　空気調和装置１で使用される冷媒は、エチレン系フルオロオレフィンを含む作動媒体である。エチレン系フルオロオレフィンは、例えば、１，１，２－トリフルオロエチレン（ＨＦＯ－１１２３）、トランス－１，２－ジフルオロエチレン（ＨＦＯ－１１３２（Ｅ））、シス－１，２－ジフルオロエチレン（ＨＦＯ－１１３２（Ｚ））、１，１－ジフルオロエチレン（ＨＦＯ－１１３２ａ）、テトラフルオロエチレン（ＣＦ２＝ＣＦ２，ＨＦＯ－１１１４）、及び、モノフルオロエチレン（ＨＦＯ－１１４１）のうちいずれか１以上を含む。 [1-3. Refrigerant]
The refrigerant used in the air conditioner 1 is a working medium containing ethylene-based fluoroolefin. Examples of ethylene-based fluoroolefins include 1,1,2-trifluoroethylene (HFO-1123), trans-1,2-difluoroethylene (HFO-1132(E)), and cis-1,2-difluoroethylene (HFO-1123). -1132 (Z)), 1,1-difluoroethylene (HFO-1132a), tetrafluoroethylene (CF 2 = CF 2 , HFO-1114), and monofluoroethylene (HFO-1141). including.
　上記作動媒体は、２以上の冷媒成分を含んでもよい。すなわち、上記の例から選択されるエチレン系フルオロオレフィン（例えば、１，１，２－トリフルオロエチレン）と、第２の冷媒成分とを含んでもよい。第２の冷媒成分としては、ハイドロフルオロカーボン（ＨＦＣ）、ハイドロフルオロオレフィン（ＨＦＯ）、飽和炭化水素、二酸化炭素、或いはその他の冷媒から選択される１以上の冷媒が挙げられる。このハイドロフルオロカーボンとしては、例えば、ジフルオロメタン、ジフルオロエタン、トリフルオロエタン、テトラフルオロエタン、ペンタフルオロエタン、ペンタフルオロプロパン、ヘキサフルオロプロパン、ヘプタフルオロプロパン、ペンタフルオロブタン、ヘプタフルオロシクロペンタンが挙げられる。ハイドロフルオロオレフィンとしては、例えば、モノフルオロプロペン、トリフルオロプロペン、テトラフルオロプロペン、ペンタフルオロプロペン、ヘキサフルオロブテンが挙げられる。飽和炭化水素は、例えば、エタン、ｎ－プロパン、シクロプロパン、ｎ－ブタン、シクロブタン、イソブタン（２－メチルプロパン）、メチルシクロプロパン、ｎ－ペンタン、イソペンタン（２－メチルブタン）、ネオペンタン（２，２－ジメチルプロパン）、メチルシクロブタンが挙げられるが、その他の炭化水素であってもよい。第２の冷媒成分は、複数の成分を含んでもよい。すなわち、第２の冷媒成分は、ハイドロフルオロカーボン、ハイドロフルオロオレフィン、飽和炭化水素、二酸化炭素、及び、その他の冷媒の中から選択される２以上の冷媒成分を含んでもよい。 The working medium may include two or more refrigerant components. That is, it may contain an ethylene-based fluoroolefin (for example, 1,1,2-trifluoroethylene) selected from the above examples and a second refrigerant component. The second refrigerant component may include one or more refrigerants selected from hydrofluorocarbons (HFCs), hydrofluoroolefins (HFOs), saturated hydrocarbons, carbon dioxide, or other refrigerants. Examples of the hydrofluorocarbon include difluoromethane, difluoroethane, trifluoroethane, tetrafluoroethane, pentafluoroethane, pentafluoropropane, hexafluoropropane, heptafluoropropane, pentafluorobutane, and heptafluorocyclopentane. Examples of the hydrofluoroolefins include monofluoropropene, trifluoropropene, tetrafluoropropene, pentafluoropropene, and hexafluorobutene. Saturated hydrocarbons include, for example, ethane, n-propane, cyclopropane, n-butane, cyclobutane, isobutane (2-methylpropane), methylcyclopropane, n-pentane, isopentane (2-methylbutane), neopentane (2,2 -dimethylpropane) and methylcyclobutane, but other hydrocarbons may also be used. The second refrigerant component may include multiple components. That is, the second refrigerant component may include two or more refrigerant components selected from hydrofluorocarbons, hydrofluoroolefins, saturated hydrocarbons, carbon dioxide, and other refrigerants.
　空気調和装置１で冷媒として使用される作動媒体は、冷媒成分に加え、不均化抑制剤を含んでもよい。不均化抑制剤は、例えば、飽和炭化水素である。作動媒体は、１または複数の成分からなる不均化抑制剤を含んでもよい。不均化抑制剤として利用される飽和炭化水素は、エタン、ｎ－プロパン、シクロプロパン、ｎ－ブタン、シクロブタン、イソブタン（２－メチルプロパン）、メチルシクロプロパン、ｎ－ペンタン、イソペンタン（２－メチルブタン）、ネオペンタン（２，２－ジメチルプロパン）、メチルシクロブタンが挙げられるが、その他の飽和炭化水素であってもよい。特に好ましい不均化抑制剤として、ｎ－プロパンが挙げられる。 The working medium used as a refrigerant in the air conditioner 1 may contain a disproportionation inhibitor in addition to the refrigerant components. Disproportionation inhibitors are, for example, saturated hydrocarbons. The working medium may include a disproportionation inhibitor consisting of one or more components. Saturated hydrocarbons utilized as disproportionation inhibitors include ethane, n-propane, cyclopropane, n-butane, cyclobutane, isobutane (2-methylpropane), methylcyclopropane, n-pentane, isopentane (2-methylbutane). ), neopentane (2,2-dimethylpropane), and methylcyclobutane, but other saturated hydrocarbons may also be used. A particularly preferred disproportionation inhibitor is n-propane.
　不均化抑制剤は、例えば、炭素数が１から２のいずれかであるハロアルカンであってもよい。不均化抑制剤として利用される炭素数１のハロアルカン、すなわちハロメタンとしては、例えば、（モノ）ヨードメタン（ＣＨ３Ｉ）、ジヨードメタン（ＣＨ２Ｉ２）、ジブロモメタン（ＣＨ２Ｂｒ２）、ブロモメタン（ＣＨ３Ｂｒ）、ジクロロメタン（ＣＨ２Ｃｌ２）、クロロヨードメタン（ＣＨ２ＣｌＩ）、ジブロモクロロメタン（ＣＨＢｒ２Ｃｌ）、四ヨウ化メタン（ＣＩ４）、四臭化炭素（ＣＢｒ４）、ブロモトリクロロメタン（ＣＢｒＣｌ３）、ジブロモジクロロメタン（ＣＢｒ２Ｃｌ２）、トリブロモフルオロメタン（ＣＢｒ３Ｆ）、フルオロジヨードメタン（ＣＨＦＩ２）、ジフルオロヨードメタン（ＣＨＦ２Ｉ）、ジフルオロジヨードメタン（ＣＦ２Ｉ２）、ジブロモジフルオロメタン（ＣＢｒ２Ｆ２）、トリフルオロヨードメタン（ＣＦ３Ｉ）が挙げられるが、その他のハロメタンであってもよい。不均化抑制剤として利用される炭素数２のハロアルカン、すなわちハロエタンとしては、例えば、１，１，１－トリフルオロ－２－ヨードエタン（ＣＦ３ＣＨ２Ｉ）、モノヨードエタン（ＣＨ３ＣＨ２Ｉ）、モノブロモエタン（ＣＨ３ＣＨ２Ｂｒ）、１，１，１－トリヨードエタン（ＣＨ３ＣＩ３）が挙げられる。 The disproportionation inhibitor may be, for example, a haloalkane having 1 to 2 carbon atoms. Examples of haloalkanes having one carbon number, ie, halomethanes, used as disproportionation inhibitors include (mono)iodomethane (CH 3 I), diiodomethane (CH 2 I 2 ), dibromomethane (CH 2 Br 2 ), and bromomethane. (CH 3 Br), dichloromethane (CH 2 Cl 2 ), chloroiodomethane (CH 2 ClI), dibromochloromethane (CHBr 2 Cl), tetraiodide methane (CI 4 ), carbon tetrabromide (CBr 4 ), Bromotrichloromethane (CBrCl 3 ), dibromodichloromethane (CBr 2 Cl 2 ), tribromofluoromethane (CBr 3 F), fluorodiiodomethane (CHFI 2 ), difluoroiodomethane (CHF 2 I), difluorodiiodomethane ( CF 2 I 2 ), dibromodifluoromethane (CBr 2 F 2 ), and trifluoroiodomethane (CF 3 I), but other halomethanes may also be used. Examples of the haloalkane having 2 carbon atoms, that is, haloethane, used as a disproportionation inhibitor include 1,1,1-trifluoro-2-iodoethane (CF 3 CH 2 I), monoiodoethane (CH 3 CH 2 I), monobromoethane (CH 3 CH 2 Br), and 1,1,1-triiodoethane (CH 3 CI 3 ).
　作動媒体は、上記の飽和炭化水素、及び、上記のハロアルカンから選択される複数の不均化抑制剤を含んでもよい。また、作動媒体は、１種類の飽和炭化水素を含んでもよいし、２種類以上の飽和炭化水素を含む作動媒体であってもよい。また、作動媒体は、１種類のハロアルカンを含んでもよいし、２種類以上のハロアルカンを含む作動媒体であってもよい。 The working medium may include a plurality of disproportionation inhibitors selected from the above-mentioned saturated hydrocarbons and the above-mentioned haloalkanes. Further, the working medium may contain one type of saturated hydrocarbon or may contain two or more types of saturated hydrocarbons. Further, the working medium may contain one type of haloalkane, or may contain two or more types of haloalkanes.
　作動媒体の好ましい例として、１，１，２－トリフルオロエチレンと、ｎ－プロパンとを含む混合物が挙げられる。この作動媒体は、上述した第２の冷媒成分を含んでもよいし、その他の成分を含んでもよい。 A preferred example of the working medium is a mixture containing 1,1,2-trifluoroethylene and n-propane. This working medium may contain the second refrigerant component described above, or may contain other components.
　上記の各作動媒体は、不可避不純物を含み得る。不可避不純物としては、輸送中や保管中における安定化を目的として添加された安定化剤を含む各種の添加剤、冷媒成分の合成原料の残部または副生物、及び、その他の理由により混入する物質が挙げられる。 Each of the above working media may contain unavoidable impurities. Unavoidable impurities include various additives including stabilizers added for the purpose of stabilization during transportation and storage, residues or by-products of synthetic raw materials for refrigerant components, and substances mixed in for other reasons. Can be mentioned.
　作動媒体に含まれる１，１，２－トリフルオロエチレンと、ｎ－プロパンとの質量比は適宜に変更が可能である。冷凍サイクルの能力は、作動媒体に含まれる冷媒成分の質量比に相関する。従って、冷凍サイクルの能力を維持するためには、不均化抑制剤であるｎ－プロパンは、作動媒体に４０質量％以下の質量だけ含まれるように構成することが望ましい。 The mass ratio of 1,1,2-trifluoroethylene and n-propane contained in the working medium can be changed as appropriate. The capacity of a refrigeration cycle is correlated to the mass ratio of refrigerant components contained in the working medium. Therefore, in order to maintain the performance of the refrigeration cycle, it is desirable that the working medium contains n-propane, which is a disproportionation inhibitor, in an amount of 40% by mass or less.
　［１－４．不均化反応の抑制］
　エチレン系フルオロオレフィンは、例えば、不均化反応が生じるエチレン系フルオロオレフィンを含む。エチレン系フルオロオレフィンを冷媒として利用する場合、ＧＷＰが低く、冷凍能力が高いという利点がある。その反面、エチレン系フルオロオレフィンは易分解性の冷媒に属するので、特定の条件下で不均化反応が発生する可能性がある。不均化反応は、冷媒に含まれる分子からラジカルが生成し、連鎖反応により冷媒の自己分解が進行する反応として知られている。不均化反応が発生すると、冷凍サイクルにおける急激な圧力上昇を招く。 [1-4. Suppression of disproportionation reaction]
Ethylene-based fluoroolefins include, for example, ethylene-based fluoroolefins in which a disproportionation reaction occurs. When using ethylene-based fluoroolefins as refrigerants, there are advantages of low GWP and high refrigerating capacity. On the other hand, since ethylene-based fluoroolefins belong to easily decomposable refrigerants, disproportionation reactions may occur under certain conditions. The disproportionation reaction is known as a reaction in which radicals are generated from molecules contained in a refrigerant, and self-decomposition of the refrigerant progresses due to a chain reaction. When a disproportionation reaction occurs, it causes a sudden pressure increase in the refrigeration cycle.
　不均化反応が発生し得る特定の条件とは、冷媒が高温であること、高圧であること、及び、冷媒が放電現象に晒されることが挙げられる。換言すれば、高温、高圧、及び放電現象のいずれかを排除または防止することによって、冷媒の不均化反応を防止または抑制できる。不均化反応を誘発する放電現象の典型的な例は、電動機１１０において、固定子１１１の固定子巻線間で発生する短絡である。この種の短絡はレイヤーショート、或いはレアショートと呼ばれる。 The specific conditions under which the disproportionation reaction can occur include the refrigerant being at a high temperature, the refrigerant being under high pressure, and the refrigerant being exposed to an electrical discharge phenomenon. In other words, the disproportionation reaction of the refrigerant can be prevented or suppressed by eliminating or preventing any of high temperature, high pressure, and discharge phenomena. A typical example of a discharge phenomenon that induces a disproportionation reaction is a short circuit that occurs between stator windings of stator 111 in electric motor 110. This type of short circuit is called a layer short or a layer short.
　本実施の形態の空気調和装置１は、冷媒の不均化反応を抑制する構成を備える。
　圧縮機１００は、内部低圧型である。このため、容器１０２の内部の冷媒圧力は、圧縮機構１２０の吸込側の圧力に等しいことから、電動機１１０及びその周囲において冷媒が高温かつ高圧の状態となりにくい。従って、仮に電動機１１０でレイヤーショートが発生した場合であっても、冷媒の不均化反応が誘発されにくい。 The air conditioner 1 of this embodiment includes a configuration that suppresses the disproportionation reaction of the refrigerant.
Compressor 100 is of internal low pressure type. Therefore, since the refrigerant pressure inside the container 102 is equal to the pressure on the suction side of the compression mechanism 120, the refrigerant is unlikely to reach a high temperature and high pressure state in and around the electric motor 110. Therefore, even if a layer short occurs in the electric motor 110, a disproportionation reaction of the refrigerant is unlikely to be induced.
　容器１０２の内部では、吸込口１０４から吸い込まれた冷媒が固定子１１１と回転子１１２との間のエアギャップを通って圧縮機構１２０に達するので、エアギャップを通る冷媒により電動機１１０の温度の上昇が抑制される。従って、電動機１１０及びその周囲の冷媒が高温かつ高圧の状態となりにくいので、仮に電動機１１０でレイヤーショートが発生した場合であっても、冷媒の不均化反応が誘発されにくい。 Inside the container 102, the refrigerant sucked in from the suction port 104 passes through the air gap between the stator 111 and the rotor 112 and reaches the compression mechanism 120, so the temperature of the electric motor 110 increases due to the refrigerant passing through the air gap. is suppressed. Therefore, the electric motor 110 and the refrigerant around it are unlikely to reach a high temperature and high pressure state, so even if a layer short occurs in the electric motor 110, a disproportionation reaction of the refrigerant is unlikely to be induced.
　空気調和装置１は、圧縮機１００の圧縮室に液体の冷媒を供給する配管４３及びインジェクション部１２５を備える。制御装置１０は、圧縮機１００の温度が予め設定された条件を満たす場合に弁１６を開き、インジェクション部１２５に冷媒を供給させる。予め設定された条件は、例えば、圧縮機１００の温度が閾値以上となることである。圧縮機１００の温度とは、詳細には、電動機１１０の温度、または、圧縮機構１２０の吐出冷媒の温度である。この場合、制御装置１０は、電動機１１０の温度、或いは、圧縮機構１２０の吐出冷媒の温度が閾値を超えたことを検知すると弁１６を開かせる。これにより、圧縮機構１２０を冷却することができ、不均化反応を抑制できる。 The air conditioner 1 includes a pipe 43 and an injection section 125 that supply liquid refrigerant to the compression chamber of the compressor 100. The control device 10 opens the valve 16 when the temperature of the compressor 100 satisfies a preset condition, and causes the injection section 125 to supply refrigerant. The preset condition is, for example, that the temperature of the compressor 100 is equal to or higher than a threshold value. Specifically, the temperature of the compressor 100 is the temperature of the electric motor 110 or the temperature of the refrigerant discharged from the compression mechanism 120. In this case, the control device 10 opens the valve 16 when detecting that the temperature of the electric motor 110 or the temperature of the refrigerant discharged from the compression mechanism 120 exceeds a threshold value. Thereby, the compression mechanism 120 can be cooled, and the disproportionation reaction can be suppressed.
　ここで、弁１６が開かれた場合、気液分離器１５から配管４３に冷媒が流出することに伴って気液分離器１５における冷媒の圧力を低下させ、気液分離器１５で冷媒を膨張させることができる。これにより、気液分離器１５は一種の熱交換器として機能するので、例えば、気液分離器１５を中間冷却器と呼ぶことができる。この作用により、空気調和装置１の冷房運転状態で、圧縮機１００から吐出された冷媒は膨張弁１４、及び、気液分離器１５において、二段階に減圧される。すなわち、膨張弁１４及び気液分離器１５が２段階の膨張機構を構成する。冷房運転状態で冷媒が高温高圧となる領域は、図１に符号ＨＰで示す領域である。膨張弁１４及び気液分離器１５が２段階の膨張機構を構成することによって、領域ＨＰを狭い範囲に限定することができる。このため、仮に冷媒の不均化反応が発生した場合に、冷媒の連鎖反応が伝搬する範囲を狭くすることができる。さらに、２段階の膨張過程を構成することによって、圧縮機構１２０の温度を下げることができ、不均化反応をより効果的に抑制できる。 Here, when the valve 16 is opened, the pressure of the refrigerant in the gas-liquid separator 15 is reduced as the refrigerant flows out from the gas-liquid separator 15 to the pipe 43, and the refrigerant is expanded in the gas-liquid separator 15. can be done. Thereby, the gas-liquid separator 15 functions as a type of heat exchanger, and therefore, the gas-liquid separator 15 can be called an intercooler, for example. Due to this action, the refrigerant discharged from the compressor 100 is depressurized in two stages in the expansion valve 14 and the gas-liquid separator 15 when the air conditioner 1 is in a cooling operation state. That is, the expansion valve 14 and the gas-liquid separator 15 constitute a two-stage expansion mechanism. The region where the refrigerant becomes high temperature and high pressure in the cooling operation state is the region indicated by the symbol HP in FIG. 1 . Since the expansion valve 14 and the gas-liquid separator 15 constitute a two-stage expansion mechanism, the region HP can be limited to a narrow range. Therefore, even if a refrigerant disproportionation reaction occurs, the range in which the refrigerant chain reaction propagates can be narrowed. Furthermore, by configuring a two-stage expansion process, the temperature of the compression mechanism 120 can be lowered, and the disproportionation reaction can be suppressed more effectively.
　空気調和装置１は、制御装置１０により弁１６の開閉を制御可能であり、例えば、不均化反応が発生する可能性が低い状態では弁１６を閉じる。そのため、空気調和装置１の運転効率を高めることができる。 The air conditioner 1 can control the opening and closing of the valve 16 by the control device 10, and for example, closes the valve 16 in a state where the possibility of a disproportionation reaction occurring is low. Therefore, the operating efficiency of the air conditioner 1 can be improved.
　空気調和装置１は、リリーフバルブ６０を備える。そのため、仮に不均化反応が発生した場合であっても、不均化反応に伴う冷媒圧力の上昇に対応してリリーフバルブ６０が開くことにより、冷凍サイクルにおける圧力の過度の上昇を防止できる。 The air conditioner 1 includes a relief valve 60. Therefore, even if a disproportionation reaction occurs, the relief valve 60 opens in response to the increase in refrigerant pressure accompanying the disproportionation reaction, thereby preventing an excessive increase in pressure in the refrigeration cycle.
　さらに、上述したように、エチレン系フルオロオレフィンと、不均化抑制剤とを含む冷媒を空気調和装置１に用いることにより、冷媒の不均化反応を抑制する。不活性な不均化抑制剤を含む冷媒は、熱希釈効果によりエチレン系フルオロオレフィンの不均化反応を抑制する。また、ある種の不均化抑制剤は、不均化反応で生じる活性な中間生成物であるラジカルを捕捉する。これにより、反応の初期段階で発生するラジカルを捕捉することによって連鎖反応を予防すること、及び、連鎖反応の伝搬を抑制することができる。これらの作用により、冷媒の不均化反応を抑制できる。 Further, as described above, by using a refrigerant containing an ethylene-based fluoroolefin and a disproportionation inhibitor in the air conditioner 1, the disproportionation reaction of the refrigerant is suppressed. A refrigerant containing an inert disproportionation inhibitor suppresses the disproportionation reaction of ethylene-based fluoroolefins due to its thermodilution effect. Additionally, certain disproportionation inhibitors scavenge radicals, which are active intermediates produced in disproportionation reactions. Thereby, it is possible to prevent a chain reaction by trapping radicals generated in the initial stage of the reaction, and to suppress the propagation of the chain reaction. These effects can suppress the disproportionation reaction of the refrigerant.
　［１－５．制御装置による制御］
　ここで、制御装置１０が冷媒の不均化反応を抑制する制御について説明する。
　制御装置１０は、上述したように、圧縮機１００の温度が予め設定された条件を満たす場合に弁１６を開く制御を行う。
　また、制御装置１０は、四方弁２１、２２、及び、その他の弁を動作させることによって、不均化反応を抑制する。 [1-5. Control by control device]
Here, a description will be given of control by which the control device 10 suppresses the disproportionation reaction of the refrigerant.
As described above, the control device 10 controls the opening of the valve 16 when the temperature of the compressor 100 satisfies a preset condition.
Further, the control device 10 suppresses the disproportionation reaction by operating the four- way valves 21, 22 and other valves.
　図４は、制御装置１０の動作を示すフローチャートである。
　制御装置１０は、空気調和装置１の運転中、空気調和装置１の高圧部における冷媒圧力が閾値以上に上昇したか否かを監視する（ステップＳ１１）。高圧部とは、空気調和装置１において高圧の冷媒が流れる範囲であり、例えば、圧縮機構１２０、吐出管１０５、及び、図１に示す領域ＨＰのいずれかを含む。ここでは、制御装置１０が圧縮機構１２０の吐出冷媒の圧力について判定を行う例を説明する。 FIG. 4 is a flowchart showing the operation of the control device 10.
During operation of the air conditioner 1, the control device 10 monitors whether the refrigerant pressure in the high pressure section of the air conditioner 1 has increased to a threshold value or more (step S11). The high-pressure section is a range in which high-pressure refrigerant flows in the air conditioner 1, and includes, for example, any one of the compression mechanism 120, the discharge pipe 105, and the region HP shown in FIG. Here, an example will be described in which the control device 10 determines the pressure of the refrigerant discharged from the compression mechanism 120.
　圧力が閾値より低い場合（ステップＳ１１；ＮＯ）、制御装置１０は、ステップＳ１１の監視を所定時間周期で継続する。閾値は、予め制御装置１０に設定される。閾値は、圧縮機１００における冷媒の不均化反応が発生したと推定される圧力、または、不均化反応が発生する可能性が高い圧力の値である。
　制御装置１０によって、圧縮機１００の吐出冷媒の圧力が閾値以上に上昇したと判定された場合（ステップＳ１１；ＹＥＳ）、空気調和装置１の高圧部において冷媒の不均化反応が発生した可能性が高い。この場合、図４には示さないが、制御装置１０は、弁１６を開いてインジェクション部１２５から圧縮機構１２０に冷媒を流入させる制御を行わない。さらに、制御装置１０は、弁１６を閉じる制御を行ってもよい。 If the pressure is lower than the threshold (step S11; NO), the control device 10 continues monitoring in step S11 at predetermined time intervals. The threshold value is set in advance in the control device 10. The threshold value is the pressure at which the refrigerant disproportionation reaction in the compressor 100 is estimated to have occurred, or the value of the pressure at which the disproportionation reaction is likely to occur.
If the control device 10 determines that the pressure of the refrigerant discharged from the compressor 100 has increased above the threshold value (step S11; YES), there is a possibility that a refrigerant disproportionation reaction has occurred in the high pressure section of the air conditioner 1. is high. In this case, although not shown in FIG. 4, the control device 10 does not perform control to open the valve 16 and cause the refrigerant to flow from the injection section 125 into the compression mechanism 120. Furthermore, the control device 10 may perform control to close the valve 16.
　制御装置１０は、高圧部の圧力が閾値以上に上昇したと判定した場合（ステップＳ１１；ＹＥＳ）、空気調和装置１が暖房運転中か否かを判定する（ステップＳ１２）。空気調和装置１が暖房運転中である場合（ステップＳ１２；ＹＥＳ）、制御装置１０は、四方弁２１及び四方弁２２を動作させて、空気調和装置１を冷房運転に切り替える（ステップＳ１３）。 When the control device 10 determines that the pressure in the high pressure section has increased to the threshold value or more (step S11; YES), the control device 10 determines whether the air conditioner 1 is in heating operation (step S12). When the air conditioner 1 is in heating operation (step S12; YES), the control device 10 operates the four-way valve 21 and the four-way valve 22 to switch the air conditioner 1 to cooling operation (step S13).
　空気調和装置１の暖房運転中は、熱交換器１１ａ及び熱交換器１１ｂに高圧の冷媒が流れているため、冷媒の不均化反応が熱交換器１１ａ、１１ｂに伝搬する可能性がある。これに対し、空気調和装置１が冷房運転を行うと、高圧の冷媒が流れる範囲は図１の領域ＨＰに限られる。このため、ステップＳ１３で空気調和装置１の運転状態を冷房運転状態に切り替えることにより、不均化反応が被調和空間に近い位置に伝搬することを回避できる。これにより、不均化反応に伴う急激な圧力上昇によって、被調和空間に近い機器が破損することを予防できるので、被調和空間にいる人に影響を与えないという利点がある。 During the heating operation of the air conditioner 1, high-pressure refrigerant is flowing through the heat exchangers 11a and 11b, so there is a possibility that the disproportionation reaction of the refrigerant will propagate to the heat exchangers 11a and 11b. On the other hand, when the air conditioner 1 performs cooling operation, the range through which the high-pressure refrigerant flows is limited to the region HP in FIG. 1 . Therefore, by switching the operating state of the air conditioner 1 to the cooling operating state in step S13, it is possible to prevent the disproportionation reaction from propagating to a position close to the conditioned space. This makes it possible to prevent equipment close to the harmonized space from being damaged due to the sudden pressure increase accompanying the disproportionation reaction, which has the advantage of not affecting people in the harmonized space.
　空気調和装置１が冷房運転中である場合（ステップＳ１２；ＮＯ）、及び、空気調和装置１を暖房運転状態から冷房運転状態に切り替えた場合（ステップＳ１３）、制御装置１０は、制御対象の弁を第１開度まで閉じる制御を行う（ステップＳ１４）。ステップＳ１４で、制御装置１０は、少なくとも膨張弁１４を、第１開度まで閉じる。制御装置１０は、ステップＳ１４で、膨張弁１２ａ、１２ｂを第１開度まで閉じる制御を行ってもよい。 When the air conditioner 1 is in cooling operation (step S12; NO) and when the air conditioner 1 is switched from the heating operation state to the cooling operation state (step S13), the control device 10 controls the valve to be controlled. Control is performed to close the opening to the first opening degree (step S14). In step S14, the control device 10 closes at least the expansion valve 14 to the first opening degree. The control device 10 may perform control to close the expansion valves 12a and 12b to the first opening degree in step S14.
　第１開度は、全閉状態よりも弁が開いた状態となる所定の開度である。第１開度は、それぞれの弁に対応して設定された値であってもよいし、全ての弁に共通する設定値であってもよい。例えば、全開を１００％とする場合に、第１開度を１０％とすることができる。制御装置１０が弁を閉じることによって、弁を超えて不均化反応が伝搬することを抑制できる。また、弁を全閉すると、不均化反応に伴う圧力上昇をより急激な変化にしてしまう可能性があるため、全閉ではなく第１開度とすることが有効である。 The first opening degree is a predetermined opening degree at which the valve is in an open state rather than a fully closed state. The first opening degree may be a value set corresponding to each valve, or may be a set value common to all valves. For example, when fully opening is 100%, the first opening degree can be 10%. When the control device 10 closes the valve, propagation of the disproportionation reaction beyond the valve can be suppressed. Further, if the valve is fully closed, the pressure increase due to the disproportionation reaction may change more rapidly, so it is effective to set the valve to the first opening degree instead of fully closing the valve.
　制御装置１０は、高圧部の圧力の上昇が停止したか否かを監視する（ステップＳ１５）。圧力の上昇が停止していない場合は（ステップＳ１５；ＮＯ）、ステップＳ１５の監視を所定時間周期で継続する。圧力の上昇が停止したと判定した場合（ステップＳ１５；ＹＥＳ）、制御装置１０は、ステップＳ１４で第１開度まで閉めた弁を全閉状態まで閉じる制御を行う（ステップＳ１６）。その後、制御装置１０は、報知を実行する（ステップＳ１７）。ステップＳ１７の報知は、空気調和装置１を管理する管理者に対し、不均化反応の発生を知らせることができればよく、その態様は制限されない。例えば、制御装置１０は、ステップＳ１７で、空気調和装置１を管理する装置に不均化反応の発生を通知してもよいし、空気調和装置１を操作するリモコン装置のディスプレイに表示を行わせてもよいし、空気調和装置１の室内ユニットが有するディスプレイに表示を行わせてもよい。また、制御装置１０の制御により音や画像を出力してもよい。 The control device 10 monitors whether the increase in pressure in the high pressure section has stopped (step S15). If the increase in pressure has not stopped (step S15; NO), monitoring in step S15 is continued at predetermined time intervals. If it is determined that the increase in pressure has stopped (step S15; YES), the control device 10 performs control to close the valve, which was closed to the first opening degree in step S14, to a fully closed state (step S16). After that, the control device 10 executes notification (step S17). The notification in step S17 is not limited as long as it can notify the administrator of the air conditioner 1 of the occurrence of the disproportionation reaction. For example, in step S17, the control device 10 may notify the device that manages the air conditioner 1 of the occurrence of the disproportionation reaction, or cause the display of the remote control device that operates the air conditioner 1 to display the occurrence of the disproportionation reaction. Alternatively, the display may be displayed on a display included in the indoor unit of the air conditioner 1. Furthermore, sounds and images may be output under the control of the control device 10.
　図４の制御において、制御装置１０は、ステップＳ１２～Ｓ１６のいずれかの時点で圧縮機１００を停止させてもよい。
　制御装置１０は、上記のステップＳ１１及びステップＳ１５で、圧縮機１００の吐出冷媒の温度や、熱交換器１１ａ、１１ｂ、熱交換器１３の温度に基づき圧縮機１００の吐出冷媒の圧力を推定し、推定した圧力について判定を行ってもよい。 In the control shown in FIG. 4, the control device 10 may stop the compressor 100 at any of steps S12 to S16.
In step S11 and step S15 described above, the control device 10 estimates the pressure of the refrigerant discharged from the compressor 100 based on the temperature of the refrigerant discharged from the compressor 100 and the temperatures of the heat exchangers 11a, 11b and the heat exchanger 13. , the estimated pressure may be determined.
　上記の説明では、ステップＳ１１及びステップＳ１５で制御装置１０が圧縮機１００の吐出冷媒の圧力を判定する例を示したが、これは一例である。制御装置１０は、例えば、圧縮機１００の吐出冷媒の温度に基づき判定を行ってもよい。この場合、制御装置１０は、圧縮機１００の吐出冷媒の温度を温度センサにより直接検出してもよいし、吐出冷媒の圧力、或いは、熱交換器１１ａ、１１ｂ、熱交換器１３の温度に基づき推定した圧縮機１００の吐出冷媒の温度をもとに、判定を行ってもよい。 In the above description, an example was shown in which the control device 10 determines the pressure of the refrigerant discharged from the compressor 100 in step S11 and step S15, but this is just an example. The control device 10 may make the determination based on the temperature of the refrigerant discharged from the compressor 100, for example. In this case, the control device 10 may directly detect the temperature of the refrigerant discharged from the compressor 100 using a temperature sensor, or may detect the temperature of the refrigerant discharged from the compressor 100 based on the pressure of the discharged refrigerant or the temperature of the heat exchangers 11a, 11b, and the heat exchanger 13. The determination may be made based on the estimated temperature of the refrigerant discharged from the compressor 100.
　空気調和装置１の四方弁２１、２２は、低差圧作動型の四方弁、又は、電磁開閉弁により構成されることが好ましい。四方弁２１、２２にパイロット形の四方切替弁を用いる構成では、低差圧作動型の四方弁、又は、電磁開閉弁を用いると、ステップＳ１３で暖房運転状態から冷房運転状態への切り替えが速やかに行われるという利点がある。 It is preferable that the four- way valves 21 and 22 of the air conditioner 1 are constituted by low differential pressure operating type four-way valves or electromagnetic on-off valves. In a configuration in which pilot-type four-way switching valves are used as the four- way valves 21 and 22, if a low differential pressure operating type four-way valve or an electromagnetic shut-off valve is used, the heating operation state can be quickly switched to the cooling operation state in step S13. It has the advantage of being carried out.
　［１－６．効果等］
　以上説明したように、実施の形態１の空気調和装置１は、圧縮機１００と、熱源側熱交換器である熱交換器１３と、利用側熱交換器である熱交換器１１ａ、１１ｂと、膨張機構と、を備える。空気調和装置１は、熱交換器１１ａ、１１ｂを凝縮器として動作させる暖房運転状態と、熱交換器１３を凝縮器として動作させる冷房運転状態と、を切り替える四方弁２１、２２と、制御装置１０と、を備える。空気調和装置１は、冷媒として、エチレン系フルオロオレフィンを含む作動媒体を使用する。制御装置１０は、暖房運転状態で圧縮機１００と凝縮器とを含む高圧部における作動媒体の圧力が閾値以上まで上昇したことを検出した場合に、四方弁２１、２２を制御して暖房運転状態から冷房運転状態への切り替えを行う。
　これにより、空気調和装置１は、エチレン系フルオロオレフィンを含む作動媒体を利用することにより低ＧＷＰ化を実現できる。さらに、空気調和装置１は、冷媒の不均化反応が発生した可能性がある場合、或いは、不均化反応が発生したと推定される場合に、空気調和装置１を暖房運転状態から冷房運転状態に切り替えて、高圧の冷媒が流れる領域ＨＰを狭くする。これにより、不均化反応によって冷媒の圧力が急激に上昇する領域ＨＰを限定することができ、冷凍サイクルにおける不均化反応の影響を抑えることができる。例えば、熱交換器１１ａ、１１ｂが空気調和装置１の被調和空間またはその近傍に設置される場合、制御装置１０の制御により、不均化反応の影響が被調和空間に及ぶことを防止または抑制できる。 [1-6. Effects, etc.]
As described above, the air conditioner 1 of the first embodiment includes the compressor 100, the heat exchanger 13 which is the heat source side heat exchanger, and the heat exchangers 11a and 11b which are the usage side heat exchangers. An expansion mechanism. The air conditioner 1 includes four- way valves 21 and 22 that switch between a heating operation state in which the heat exchangers 11a and 11b operate as condensers and a cooling operation state in which the heat exchanger 13 operates as a condenser, and a control device 10. and. The air conditioner 1 uses a working medium containing ethylene-based fluoroolefin as a refrigerant. When the control device 10 detects that the pressure of the working medium in the high-pressure section including the compressor 100 and the condenser has increased to a threshold value or more in the heating operation state, the control device 10 controls the four- way valves 21 and 22 to return to the heating operation state. Switch from to cooling operation state.
Thereby, the air conditioner 1 can realize a low GWP by using a working medium containing ethylene-based fluoroolefin. Further, the air conditioner 1 switches the air conditioner 1 from the heating operation state to the cooling operation when there is a possibility that a refrigerant disproportionation reaction has occurred, or when it is estimated that a disproportionation reaction has occurred. state to narrow the region HP through which high-pressure refrigerant flows. Thereby, the region HP where the pressure of the refrigerant rapidly increases due to the disproportionation reaction can be limited, and the influence of the disproportionation reaction on the refrigeration cycle can be suppressed. For example, when the heat exchangers 11a and 11b are installed in or near the conditioned space of the air conditioner 1, the control of the control device 10 prevents or suppresses the influence of the disproportionation reaction from reaching the conditioned space. can.
　膨張機構は、凝縮器の出口に配置された膨張弁１４または膨張弁１２ａ、１２ｂを含む。空気調和装置１は、膨張弁１２ａ、１２ｂ、１４を制御する制御装置１０を備える。制御装置１０は、空気調和装置１の高圧部における作動媒体の圧力が閾値以上まで上昇したことを検出した場合に、膨張弁１２ａ、１２ｂ、１４のいずれかを第１開度まで閉方向に動作させ、その後、高圧部における作動媒体の圧力の上昇が停止した場合に膨張弁を第２開度まで閉方向に動作させる。第２開度は、例えば、全閉の状態である。高圧部は、例えば、圧縮機１００と凝縮器とを含む。
　これにより、冷媒の不均化反応が発生した可能性がある場合、或いは、不均化反応が発生したと推定される場合に、不均化反応に伴う圧力上昇を抑制できる。そして、高圧部の圧力の上昇が停止した後に、弁を第２開度まで閉じることによって、不均化反応の伝搬をより確実に抑制できる。 The expansion mechanism includes an expansion valve 14 or expansion valves 12a, 12b located at the outlet of the condenser. The air conditioner 1 includes a control device 10 that controls expansion valves 12a, 12b, and 14. The control device 10 operates one of the expansion valves 12a, 12b, and 14 in the closing direction to a first opening degree when it is detected that the pressure of the working medium in the high-pressure part of the air conditioner 1 has increased to a threshold value or more. Then, when the pressure of the working medium in the high pressure section stops increasing, the expansion valve is operated in the closing direction to the second opening degree. The second opening degree is, for example, a fully closed state. The high pressure section includes, for example, a compressor 100 and a condenser.
Thereby, when there is a possibility that a disproportionation reaction of the refrigerant has occurred, or when it is estimated that a disproportionation reaction has occurred, it is possible to suppress the pressure increase associated with the disproportionation reaction. Then, by closing the valve to the second opening degree after the pressure rise in the high-pressure section has stopped, propagation of the disproportionation reaction can be suppressed more reliably.
　空気調和装置１は、圧縮機１００が圧縮された冷媒を吐出する配管４２に、配管４２の圧力が設定圧以上の場合に圧力を開放するリリーフバルブ６０を有する。
　これにより、不均化反応が発生することに伴って配管４２の圧力が急激に上昇した場合に、配管４２の圧力を解放することができ、不均化反応による影響を軽減できる。 The air conditioner 1 includes a relief valve 60 in a pipe 42 through which the compressor 100 discharges compressed refrigerant, which releases the pressure when the pressure in the pipe 42 is equal to or higher than a set pressure.
Thereby, when the pressure in the pipe 42 suddenly increases due to the occurrence of the disproportionation reaction, the pressure in the pipe 42 can be released, and the influence of the disproportionation reaction can be reduced.
　また、空気調和装置１において、圧縮機１００は、作動媒体を吸入する吸込口１０４と、吸込口１０４から吸入された作動媒体を圧縮する圧縮機構１２０と、吸込口１０４とは異なる経路で圧縮機構１２０に作動媒体を供給するインジェクション部１２５と、を有する。圧縮機１００は、圧縮機構１２０が電動機１１０とともに容器１０２に収容され、圧縮機構１２０が容器１０２の内部の作動媒体を吸入して圧縮する内部低圧型圧縮機である。冷房運転状態において、凝縮器は熱交換器１３であり、蒸発器は熱交換器１１ａ、１１ｂである。暖房運転状態において、凝縮器は熱交換器１１ａ、１１ｂであり、蒸発器は熱交換器１３である。
　これにより、空気調和装置１は、エチレン系フルオロオレフィンを含む作動媒体を利用することにより低ＧＷＰ化を実現できる。さらに、インジェクション部１２５から冷媒を圧縮機構１２０に供給すること、及び、容器１０２の内部の作動媒体を低圧にすることによって、エチレン系フルオロオレフィンの不均化反応が発生しにくい構成を実現する。従って、ＧＷＰの低い冷媒を利用する場合の不均化反応を抑制できる。 Further, in the air conditioner 1, the compressor 100 includes a suction port 104 that sucks in a working medium, a compression mechanism 120 that compresses the working medium sucked from the suction port 104, and a compression mechanism that is connected to a different path from the suction port 104. and an injection section 125 that supplies a working medium to 120 . The compressor 100 is an internal low-pressure type compressor in which a compression mechanism 120 is housed in a container 102 together with an electric motor 110, and the compression mechanism 120 sucks and compresses the working medium inside the container 102. In the cooling operation state, the condenser is the heat exchanger 13, and the evaporator is the heat exchangers 11a and 11b. In the heating operation state, the condenser is the heat exchanger 11a, 11b, and the evaporator is the heat exchanger 13.
Thereby, the air conditioner 1 can realize a low GWP by using a working medium containing ethylene-based fluoroolefin. Furthermore, by supplying the refrigerant from the injection section 125 to the compression mechanism 120 and by lowering the pressure of the working medium inside the container 102, a configuration in which the disproportionation reaction of the ethylene-based fluoroolefin is less likely to occur is realized. Therefore, disproportionation reactions can be suppressed when using a refrigerant with a low GWP.
　また、空気調和装置１は、凝縮器と蒸発器との間に配置される気液分離器１５と、気液分離器１５からインジェクション部１２５に気体の作動媒体を送る配管４３と、を有する。膨張機構は、凝縮器の出口に配置されて１段目の減圧機構として動作する膨張弁１４または膨張弁１２ａ、１２ｂと、気液分離器１５と、を含む２段階の膨張過程を構成する。
　これにより、空気調和装置１において高圧の冷媒が流れる領域を狭い範囲に限定することができるので、冷媒の不均化反応が伝搬しにくい構成を実現できる。さらに、２段階の膨張過程を構成することによって、圧縮機構１２０の温度上昇を抑え、不均化反応を発生しにくい構成を実現できる。 The air conditioner 1 also includes a gas-liquid separator 15 disposed between the condenser and the evaporator, and a pipe 43 that sends a gaseous working medium from the gas-liquid separator 15 to the injection section 125. The expansion mechanism constitutes a two-stage expansion process including an expansion valve 14 or expansion valves 12a, 12b disposed at the outlet of the condenser and operating as a first-stage pressure reduction mechanism, and a gas-liquid separator 15.
As a result, the region through which the high-pressure refrigerant flows in the air conditioner 1 can be limited to a narrow range, so it is possible to realize a configuration in which the disproportionation reaction of the refrigerant is difficult to propagate. Furthermore, by configuring a two-stage expansion process, a temperature rise in the compression mechanism 120 can be suppressed and a configuration in which disproportionation reactions are less likely to occur can be realized.
　空気調和装置１は、圧縮機１００の吸込口１０４に繋がる配管４１または電動機１１０を収容する容器１０２に作動媒体を流入させる配管４３を備える。空気調和装置１は、配管４３を開閉する弁１６と、弁１６を制御する制御装置１０と、を備える。制御装置１０は、圧縮機構１２０の温度が予め設定された条件を満たす場合に弁１６を開かせる制御を行う。
　これにより、圧縮機構１２０の温度が予め設定された条件を満たす場合に、気液分離器１５から配管４３を通じて冷媒を抜き取ることにより、気液分離器１５における冷媒の圧力を低下させ、気液分離器１５で冷媒を膨張させることができる。そのため、気液分離器１５を中間冷却器として作用させ、膨張弁１４、及び、気液分離器１５において、二段階の膨張過程を構成させることができる。 The air conditioner 1 includes a pipe 41 that connects to the suction port 104 of the compressor 100 or a pipe 43 that allows a working medium to flow into a container 102 that accommodates the electric motor 110. The air conditioner 1 includes a valve 16 that opens and closes the pipe 43 and a control device 10 that controls the valve 16. The control device 10 controls the valve 16 to be opened when the temperature of the compression mechanism 120 satisfies preset conditions.
As a result, when the temperature of the compression mechanism 120 satisfies preset conditions, the refrigerant is extracted from the gas-liquid separator 15 through the pipe 43, thereby reducing the pressure of the refrigerant in the gas-liquid separator 15, and separating the gas and liquid. The refrigerant can be expanded in the vessel 15. Therefore, the gas-liquid separator 15 can act as an intercooler, and a two-stage expansion process can be configured in the expansion valve 14 and the gas-liquid separator 15.
　空気調和装置１は、熱源側熱交換器である熱交換器１３と、利用側熱交換器である熱交換器１１ａ、１１ｂと、を有する。空気調和装置１は、熱交換器１１ａ、１１ｂを凝縮器として動作させる暖房運転状態と、熱交換器１３を凝縮器として動作させる冷房運転状態と、を切り替える四方弁２１、２２を備える。制御装置１０は、暖房運転状態で圧縮機１００と凝縮器とを含む高圧部における作動媒体の圧力が閾値以上まで上昇したことを検出した場合に、四方弁２１、２２を制御して暖房運転状態から冷房運転状態への切り替えを行う。
　これにより、暖房運転状態において、空気調和装置１の高圧部で不均化反応が発生したと推定される場合に、冷房運転状態に切り替えることによって高圧の冷媒が流れる領域を制限できる。これにより、不均化反応の伝搬を抑制できる。また、空気調和装置１を冷房運転状態に切り替えることにより、利用側熱交換器である熱交換器１１ａ、１１ｂに高圧の冷媒が流れなくなるので、不均化反応の影響が被調和空間に及ぶことを回避できる。 The air conditioner 1 includes a heat exchanger 13 that is a heat source side heat exchanger, and heat exchangers 11a and 11b that are usage side heat exchangers. The air conditioner 1 includes four- way valves 21 and 22 that switch between a heating operating state in which the heat exchangers 11a and 11b operate as condensers and a cooling operating state in which the heat exchanger 13 operates as a condenser. When the control device 10 detects that the pressure of the working medium in the high-pressure section including the compressor 100 and the condenser has increased to a threshold value or more in the heating operation state, the control device 10 controls the four- way valves 21 and 22 to return to the heating operation state. Switch from to cooling operation state.
Thereby, when it is estimated that a disproportionation reaction has occurred in the high pressure section of the air conditioner 1 in the heating operating state, the region through which the high-pressure refrigerant flows can be restricted by switching to the cooling operating state. Thereby, propagation of the disproportionation reaction can be suppressed. Furthermore, by switching the air conditioner 1 to the cooling operation state, high-pressure refrigerant no longer flows to the heat exchangers 11a and 11b, which are the user-side heat exchangers, so that the influence of the disproportionation reaction does not extend to the conditioned space. can be avoided.
　四方弁２１、２２は、低差圧作動型の四方弁又は電磁開閉弁で構成されてもよい。この場合、暖房運転状態において、空気調和装置１の高圧部で不均化反応が発生したと推定される場合に、速やかに冷房運転状態に切り替えることができる。 The four- way valves 21 and 22 may be configured with a low differential pressure operated four-way valve or an electromagnetic on-off valve. In this case, when it is estimated that a disproportionation reaction has occurred in the high pressure section of the air conditioner 1 in the heating operating state, it is possible to quickly switch to the cooling operating state.
　（実施の形態２）
　図５は、実施の形態２における空気調和装置２の構成を示す図である。図５に示す空気調和装置２は、本発明の冷凍回路を適用した一例である。 (Embodiment 2)
FIG. 5 is a diagram showing the configuration of the air conditioner 2 in the second embodiment. The air conditioner 2 shown in FIG. 5 is an example to which the refrigeration circuit of the present invention is applied.
　［２－１．空気調和装置の構成］
　空気調和装置２において、熱交換器１１ａ、１１ｂ、１３、膨張弁１２ａ、１２ｂ、１４、気液分離器１５、弁１６、四方弁２１、２２、配管４１～４９、及び、リリーフバルブ６０は、実施の形態１で説明した空気調和装置１と共通する。これら共通の構成には同符号を付して説明を省略する。 [2-1. Configuration of air conditioner]
In the air conditioner 2, the heat exchangers 11a, 11b, 13, the expansion valves 12a, 12b, 14, the gas-liquid separator 15, the valve 16, the four- way valves 21, 22, the pipes 41 to 49, and the relief valve 60, This is common to the air conditioner 1 described in Embodiment 1. These common components are given the same reference numerals and their explanations will be omitted.
　空気調和装置２は、圧縮機２００を有する。圧縮機２００は、第１圧縮機１００Ａと、第２圧縮機１００Ｂとを有する２段式の圧縮機である。第１圧縮機１００Ａ及び第２圧縮機１００Ｂは、インジェクション部１２５を備えていないが、この点を除いて圧縮機１００と共通の構成を有する。例えば、第１圧縮機１００Ａ及び第２圧縮機１００Ｂは、圧縮機１００と同様の吸込口１０４を有し、第１圧縮機１００Ａの吸込口１０４は、圧縮機２００全体の吸入部の一例に対応する。以下では、第１圧縮機１００Ａ及び第２圧縮機１００Ｂの構成については説明を省略する。 The air conditioner 2 has a compressor 200. The compressor 200 is a two-stage compressor that includes a first compressor 100A and a second compressor 100B. The first compressor 100A and the second compressor 100B do not include the injection section 125, but have the same configuration as the compressor 100 except for this point. For example, the first compressor 100A and the second compressor 100B have the same suction port 104 as the compressor 100, and the suction port 104 of the first compressor 100A corresponds to an example of the suction part of the entire compressor 200. do. Below, description of the configurations of the first compressor 100A and the second compressor 100B will be omitted.
　第１圧縮機１００Ａは、配管４１に接続され、配管４１から供給される気体の冷媒を圧縮して、圧縮した冷媒を接続管２０１に吐出する。接続管２０１は、第１圧縮機１００Ａの吐出側と第２圧縮機１００Ｂの吸い込み側とを接続する配管である。第２圧縮機１００Ｂは、接続管２０１から冷媒を吸い込んで圧縮し、圧縮した高圧の冷媒を配管４２に吐出する。 The first compressor 100A is connected to the pipe 41, compresses the gaseous refrigerant supplied from the pipe 41, and discharges the compressed refrigerant to the connecting pipe 201. The connecting pipe 201 is a pipe that connects the discharge side of the first compressor 100A and the suction side of the second compressor 100B. The second compressor 100B sucks refrigerant from the connecting pipe 201, compresses it, and discharges the compressed high-pressure refrigerant to the pipe 42.
　このように、第１圧縮機１００Ａは１段目の圧縮機であり、第１圧縮機構の一例に対応する。第２圧縮機１００Ｂは、２段目の圧縮機であり、第２圧縮機構の一例に対応する。 In this way, the first compressor 100A is a first-stage compressor and corresponds to an example of a first compression mechanism. The second compressor 100B is a second stage compressor and corresponds to an example of a second compression mechanism.
　接続管２０１には、インジェクション部２０２において配管４３が接続される。これにより、弁１６が開かれている状態で、気液分離器１５から配管４３に冷媒が流出することに伴って気液分離器１５における冷媒の圧力を低下させ、気液分離器１５で冷媒を膨張させることができる。これにより、実施の形態１と同様に、気液分離器１５は一種の熱交換器として機能する。この作用により、空気調和装置２の冷房運転状態で、冷媒が膨張弁１４、及び、気液分離器１５において、二段階に減圧される。すなわち、膨張弁１４及び気液分離器１５が２段階の膨張機構を構成する。冷房運転状態で冷媒が高温高圧となる領域は、空気調和装置２の高圧部であり、圧縮機２００、配管４２、４６、及び四方弁２１のいずれかを含む。膨張弁１４及び気液分離器１５が２段階の膨張機構を構成することによって、領域ＨＰを狭い範囲に限定することができる。このため、仮に冷媒の不均化反応が発生した場合に、冷媒の連鎖反応が伝搬する範囲を狭くすることができる。さらに、２段階の膨張過程を構成することによって、圧縮機構１２０の温度を下げることができ、不均化反応をより効果的に抑制できる。インジェクション部２０２は冷媒供給部の一例に対応する。 A pipe 43 is connected to the connecting pipe 201 at the injection section 202. As a result, while the valve 16 is open, the refrigerant flows out from the gas-liquid separator 15 to the pipe 43, reducing the pressure of the refrigerant in the gas-liquid separator 15, and causing the refrigerant to flow into the gas-liquid separator 15. can be expanded. Thereby, similarly to the first embodiment, the gas-liquid separator 15 functions as a type of heat exchanger. Due to this action, the pressure of the refrigerant is reduced in two stages in the expansion valve 14 and the gas-liquid separator 15 when the air conditioner 2 is in the cooling operation state. That is, the expansion valve 14 and the gas-liquid separator 15 constitute a two-stage expansion mechanism. The region where the refrigerant becomes high temperature and high pressure in the cooling operation state is a high pressure section of the air conditioner 2 and includes any one of the compressor 200, the pipes 42 and 46, and the four-way valve 21. Since the expansion valve 14 and the gas-liquid separator 15 constitute a two-stage expansion mechanism, the region HP can be limited to a narrow range. Therefore, even if a refrigerant disproportionation reaction occurs, the range in which the refrigerant chain reaction propagates can be narrowed. Furthermore, by configuring a two-stage expansion process, the temperature of the compression mechanism 120 can be lowered, and the disproportionation reaction can be suppressed more effectively. The injection unit 202 corresponds to an example of a refrigerant supply unit.
　四方弁２１及び四方弁２２は、制御装置２０に接続される。四方弁２１及び四方弁２２は、制御装置２０の制御に従って動作し、空気調和装置２の冷房運転状態と暖房運転状態とを切り替える。 The four-way valve 21 and the four-way valve 22 are connected to the control device 20. The four-way valve 21 and the four-way valve 22 operate under the control of the control device 20 to switch the air conditioner 2 between a cooling operation state and a heating operation state.
　圧縮機２００は、１つの容器に１段目の第１圧縮機構と２段目の第２圧縮機構とを収容するコンパウンド型の圧縮機であってもよい。この場合、第２圧縮機構の吸い込み側に配管４３が接続される構成であれば、図４に示す空気調和装置２と同様の作用が期待できる。 The compressor 200 may be a compound type compressor that accommodates a first compression mechanism in the first stage and a second compression mechanism in the second stage in one container. In this case, if the pipe 43 is connected to the suction side of the second compression mechanism, the same effect as the air conditioner 2 shown in FIG. 4 can be expected.
　［２－２．冷媒］
　空気調和装置２で使用される冷媒は、実施の形態１において空気調和装置１の冷媒として説明した作動媒体である。すなわち、空気調和装置２は、エチレン系フルオロオレフィンを含む作動媒体を、冷媒として使用する。この作動媒体は、２以上の冷媒成分を含んでもよい。また、空気調和装置２において冷媒として使用される作動媒体は、冷媒成分に加え、不均化抑制剤を含んでもよい。この作動媒体は、飽和炭化水素、及び、ハロアルカンから選択される複数の不均化抑制剤を含んでもよい。また、作動媒体は、１種類の飽和炭化水素を含んでもよいし、２種類以上の飽和炭化水素を含む作動媒体であってもよい。また、作動媒体は、１種類のハロアルカンを含んでもよいし、２種類以上のハロアルカンを含む作動媒体であってもよい。 [2-2. Refrigerant]
The refrigerant used in the air conditioner 2 is the working medium described as the refrigerant of the air conditioner 1 in the first embodiment. That is, the air conditioner 2 uses a working medium containing ethylene-based fluoroolefin as a refrigerant. This working medium may include two or more refrigerant components. Further, the working medium used as a refrigerant in the air conditioner 2 may include a disproportionation inhibitor in addition to the refrigerant component. The working medium may include a plurality of disproportionation inhibitors selected from saturated hydrocarbons and haloalkanes. Further, the working medium may contain one type of saturated hydrocarbon or may contain two or more types of saturated hydrocarbons. Further, the working medium may contain one type of haloalkane, or may contain two or more types of haloalkanes.
　作動媒体の好ましい例として、１，１，２－トリフルオロエチレンと、ｎ－プロパンとを含み、不可避不純物を含む混合物が挙げられる。この作動媒体は、上述した第２の冷媒成分を含んでもよいし、その他の成分を含んでもよい。 A preferred example of the working medium is a mixture containing 1,1,2-trifluoroethylene and n-propane, and containing unavoidable impurities. This working medium may contain the second refrigerant component described above, or may contain other components.
　［２－３．制御装置］
　空気調和装置２は、制御装置２０を備える。制御装置２０は、マイクロコントローラ等のプロセッサを備える。制御装置１０は、プロセッサによりプログラムを実行することにより、或いは、プログラムされたハードウェアの機能により空気調和装置２を制御する。 [2-3. Control device]
The air conditioner 2 includes a control device 20. The control device 20 includes a processor such as a microcontroller. The control device 10 controls the air conditioner 2 by executing a program using a processor or by using programmed hardware functions.
　制御装置２０は、四方弁２１、及び、四方弁２２に接続される。四方弁２１は、制御装置２０の制御によって、配管４１、４２、４４、４６の接続を切り替える。また、四方弁２２は、制御装置２０の制御によって、配管４５、４７、４８、４９の接続を切り替える。 The control device 20 is connected to a four-way valve 21 and a four-way valve 22. The four-way valve 21 switches connections between the pipes 41 , 42 , 44 , and 46 under the control of the control device 20 . Furthermore, the four-way valve 22 switches connections between the pipes 45 , 47 , 48 , and 49 under the control of the control device 20 .
　制御装置２０は、四方弁２１及び四方弁２２を動作させて、冷房運転状態と暖房運転状態とを切り替える。すなわち、空気調和装置２が冷房運転を実行する場合、制御装置２０は、四方弁２１によって配管４１と配管４４とを接続させ、配管４２と配管４６とを接続させる。また、制御装置２０は、四方弁２２によって配管４８と配管４５とを接続させ、配管４７と配管４９とを接続させる。
　空気調和装置２が暖房運転を実行する場合、制御装置２０は、四方弁２１によって配管４１と配管４６とを接続させ、配管４２と配管４４とを接続させる。また、制御装置２０は、四方弁２２によって配管４９と配管４５とを接続させ、配管４７と配管４８とを接続させる。 The control device 20 operates the four-way valve 21 and the four-way valve 22 to switch between the cooling operation state and the heating operation state. That is, when the air conditioner 2 performs cooling operation, the control device 20 connects the piping 41 and the piping 44 and connects the piping 42 and the piping 46 using the four-way valve 21. Further, the control device 20 connects the piping 48 and the piping 45 and connects the piping 47 and the piping 49 using the four-way valve 22.
When the air conditioner 2 performs heating operation, the control device 20 connects the piping 41 and the piping 46 and connects the piping 42 and the piping 44 using the four-way valve 21. Further, the control device 20 connects the piping 49 and the piping 45 and connects the piping 47 and the piping 48 using the four-way valve 22.
　制御装置２０には、膨張弁１２ａ、１２ｂ、膨張弁１４、及び、弁１６が接続される。制御装置２０は、冷房運転状態において膨張弁１４を全開状態にするとともに、膨張弁１２ａ、１２ｂの開度を調整する。制御装置２０は、暖房運転状態において膨張弁１２ａ、１２ｂを全開状態にするとともに、膨張弁１４の開度を調整する。 The expansion valves 12a, 12b, the expansion valve 14, and the valve 16 are connected to the control device 20. The control device 20 fully opens the expansion valve 14 in the cooling operation state and adjusts the opening degrees of the expansion valves 12a and 12b. The control device 20 fully opens the expansion valves 12a and 12b in the heating operation state, and adjusts the opening degree of the expansion valve 14.
　空気調和装置２は、第１圧縮機１００Ａが有する電動機および／または第２圧縮機１００Ｂが有する電動機の温度を検出する不図示の温度センサと、第２圧縮機１００Ｂが吐出する冷媒の温度を検出する不図示の温度センサと、のいずれか１以上を備えてもよい。これらの温度センサは制御装置２０に接続される。制御装置２０は、温度センサの検出値を取得することにより、電動機の温度、及び、第２圧縮機１００Ｂが吐出する冷媒の温度のいずれか、或いは両方を検出する。また、制御装置２０は、第２圧縮機１００Ｂが吐出する冷媒の温度に基づいて、第２圧縮機１００Ｂが吐出する冷媒の圧力を算出してもよい。 The air conditioner 2 includes a temperature sensor (not shown) that detects the temperature of the electric motor of the first compressor 100A and/or the electric motor of the second compressor 100B, and a temperature sensor (not shown) that detects the temperature of the refrigerant discharged by the second compressor 100B. It may also include one or more of the following: a temperature sensor (not shown); These temperature sensors are connected to the control device 20. The control device 20 detects either or both of the temperature of the electric motor and the temperature of the refrigerant discharged by the second compressor 100B by acquiring the detected value of the temperature sensor. Further, the control device 20 may calculate the pressure of the refrigerant discharged by the second compressor 100B based on the temperature of the refrigerant discharged by the second compressor 100B.
　また、空気調和装置２は、第２圧縮機１００Ｂが吐出する冷媒の圧力を検出する圧力センサを備えてもよい。また、空気調和装置２は、熱交換器１１ａ、１１ｂ、及び、熱交換器１３の温度を検出する不図示の熱交換器温度センサを備えてもよい。この場合、制御装置２０は、熱交換器温度センサの検出値に基づいて、第２圧縮機１００Ｂが吐出する冷媒の圧力や温度を算出してもよく、上述した温度センサを備えていない構成としてもよい。 Additionally, the air conditioner 2 may include a pressure sensor that detects the pressure of the refrigerant discharged by the second compressor 100B. Additionally, the air conditioner 2 may include a heat exchanger temperature sensor (not shown) that detects the temperatures of the heat exchangers 11a, 11b, and the heat exchanger 13. In this case, the control device 20 may calculate the pressure and temperature of the refrigerant discharged by the second compressor 100B based on the detected value of the heat exchanger temperature sensor. Good too.
　制御装置２０は、弁１６を開閉させる制御を実行する。弁１６は、電動弁、電磁弁或いは膨張弁により構成される。弁１６が電動弁または膨張弁である場合、制御装置２０は、弁１６の開閉の制御、及び、弁１６の開度の調整を行う。 The control device 20 executes control to open and close the valve 16. The valve 16 is composed of an electric valve, a solenoid valve, or an expansion valve. When the valve 16 is an electric valve or an expansion valve, the control device 20 controls opening and closing of the valve 16 and adjusts the degree of opening of the valve 16.
　［２－４．制御装置による制御］
　空気調和装置２は、制御装置２０の制御により、冷媒の不均化反応を抑制する。例えば、制御装置２０は、上述したように、電動機の温度または第２圧縮機１００Ｂの吐出冷媒の温度が閾値を超えた場合に弁１６を開く制御を行う。また、制御装置２０は、四方弁２１、２２、及び、その他の弁を動作させることによって、不均化反応を抑制する。 [2-4. Control by control device]
The air conditioner 2 suppresses the disproportionation reaction of the refrigerant under the control of the control device 20 . For example, as described above, the control device 20 performs control to open the valve 16 when the temperature of the electric motor or the temperature of the refrigerant discharged from the second compressor 100B exceeds a threshold value. Further, the control device 20 suppresses the disproportionation reaction by operating the four- way valves 21, 22 and other valves.
　制御装置２０は、例えば、図４を参照して説明した動作を実行する。制御装置２０は、空気調和装置２における高圧部の冷媒圧力が閾値以上に上昇した場合に、空気調和装置２を暖房運転状態から冷房運転状態に切り替える制御を実行する。ここで、空気調和装置２の高圧部は、例えば、第２圧縮機１００Ｂ、配管４２等である。 The control device 20 executes the operation described with reference to FIG. 4, for example. The control device 20 executes control to switch the air conditioner 2 from the heating operation state to the cooling operation state when the refrigerant pressure in the high pressure section of the air conditioner 2 increases to a threshold value or more. Here, the high pressure parts of the air conditioner 2 are, for example, the second compressor 100B, the piping 42, and the like.
　さらに、制御装置２０は、空気調和装置２が冷房運転中である場合、及び、空気調和装置２を暖房運転状態から冷房運転状態に切り替えた場合、制御対象の弁を第１開度まで閉じる制御を行う。そして、高圧部の圧力の上昇が停止した場合、制御装置２０は、第１開度まで閉めた弁を全閉状態まで閉じる制御を行う。その後、制御装置２０は、報知を実行する。これらの制御を実行する間、制御装置２０は、圧縮機２００を停止させてもよい。 Furthermore, when the air conditioner 2 is in the cooling operation and when the air conditioner 2 is switched from the heating operation state to the cooling operation state, the control device 20 performs control to close the valve to be controlled to the first opening degree. I do. Then, when the pressure in the high pressure section stops increasing, the control device 20 performs control to close the valve that has been closed to the first opening degree to a fully closed state. After that, the control device 20 executes the notification. While performing these controls, the control device 20 may stop the compressor 200.
　［２－５．効果等］
　以上説明したように、実施の形態２の空気調和装置２は、実施の形態１で説明した空気調和装置１と同様に、冷媒の不均化反応が発生した場合に冷凍サイクルにおける不均化反応の影響を抑えることができる。
　すなわち、空気調和装置２は、圧縮機２００と、熱源側熱交換器である熱交換器１３と、利用側熱交換器である熱交換器１１ａ、１１ｂと、膨張機構と、を備える。空気調和装置２は、熱交換器１１ａ、１１ｂを凝縮器として動作させる暖房運転状態と、熱交換器１３を凝縮器として動作させる冷房運転状態と、を切り替える四方弁２１、２２と、制御装置２０と、を備える。空気調和装置２は、冷媒として、エチレン系フルオロオレフィンを含む作動媒体を使用する。制御装置２０は、暖房運転状態で圧縮機２００と凝縮器とを含む高圧部における作動媒体の圧力が閾値以上まで上昇したことを検出した場合に、四方弁２１、２２を制御して暖房運転状態から冷房運転状態への切り替えを行う。
　これにより、空気調和装置２は、エチレン系フルオロオレフィンを含む作動媒体を利用することにより低ＧＷＰ化を実現する。さらに、空気調和装置２は、冷媒の不均化反応が発生した可能性がある場合、或いは、不均化反応が発生したと推定される場合に、空気調和装置２を暖房運転状態から冷房運転状態に切り替えて、高圧の冷媒が流れる領域ＨＰを狭くする。これにより、不均化反応によって冷媒の圧力が急激に上昇する領域を限定することができ、不均化反応の影響を抑えることができる。 [2-5. Effects, etc.]
As explained above, the air conditioner 2 of the second embodiment, like the air conditioner 1 explained in the first embodiment, responds to the disproportionation reaction in the refrigeration cycle when the refrigerant disproportionation reaction occurs. The impact of this can be suppressed.
That is, the air conditioner 2 includes a compressor 200, a heat exchanger 13 that is a heat source side heat exchanger, heat exchangers 11a and 11b that are usage side heat exchangers, and an expansion mechanism. The air conditioner 2 includes four- way valves 21 and 22 that switch between a heating operating state in which the heat exchangers 11a and 11b operate as condensers and a cooling operating state in which the heat exchanger 13 operates as a condenser, and a control device 20. and. The air conditioner 2 uses a working medium containing ethylene-based fluoroolefin as a refrigerant. When the control device 20 detects that the pressure of the working medium in the high-pressure section including the compressor 200 and the condenser has increased to a threshold value or more in the heating operation state, the control device 20 controls the four- way valves 21 and 22 to return to the heating operation state. Switch from to cooling operation state.
Thereby, the air conditioner 2 achieves low GWP by using a working medium containing ethylene-based fluoroolefins. Further, the air conditioner 2 switches the air conditioner 2 from the heating operation state to the cooling operation when there is a possibility that a refrigerant disproportionation reaction has occurred, or when it is estimated that a disproportionation reaction has occurred. state to narrow the region HP through which high-pressure refrigerant flows. Thereby, the region where the pressure of the refrigerant rapidly increases due to the disproportionation reaction can be limited, and the influence of the disproportionation reaction can be suppressed.
　空気調和装置２の膨張機構は、凝縮器の出口に配置された膨張弁１４または膨張弁１２ａ、１２ｂを含む。制御装置２０は、膨張弁１２ａ、１２ｂ、１４を制御する。制御装置２０は、空気調和装置２の高圧部における作動媒体の圧力が閾値以上まで上昇したことを検出した場合に、膨張弁１２ａ、１２ｂ、１４のいずれかを第１開度まで閉方向に動作させ、その後、高圧部における作動媒体の圧力の上昇が停止した場合に膨張弁を第２開度まで閉方向に動作させる。第２開度は、例えば、全閉の状態である。高圧部は、例えば、圧縮機１００と凝縮器とを含む。
　これにより、冷媒の不均化反応が発生した可能性がある場合、或いは、不均化反応が発生したと推定される場合に、不均化反応に伴う圧力上昇を抑制できる。そして、高圧部の圧力の上昇が停止した後に、弁を第２開度まで閉じることによって、不均化反応の伝搬をより確実に抑制できる。 The expansion mechanism of the air conditioner 2 includes an expansion valve 14 or expansion valves 12a, 12b arranged at the outlet of the condenser. The control device 20 controls the expansion valves 12a, 12b, and 14. The control device 20 operates one of the expansion valves 12a, 12b, and 14 in the closing direction to a first opening degree when it is detected that the pressure of the working medium in the high-pressure part of the air conditioner 2 has increased to a threshold value or more. Then, when the pressure of the working medium in the high pressure section stops increasing, the expansion valve is operated in the closing direction to the second opening degree. The second opening degree is, for example, a fully closed state. The high pressure section includes, for example, a compressor 100 and a condenser.
Thereby, when there is a possibility that a disproportionation reaction of the refrigerant has occurred, or when it is estimated that a disproportionation reaction has occurred, it is possible to suppress the pressure increase associated with the disproportionation reaction. Then, by closing the valve to the second opening degree after the pressure rise in the high-pressure section has stopped, propagation of the disproportionation reaction can be suppressed more reliably.
　空気調和装置２は、圧縮機２００が圧縮された冷媒を吐出する配管４２に、配管４２の圧力が設定圧以上の場合に圧力を開放するリリーフバルブ６０を有する。
　これにより、不均化反応が発生することに伴って配管４２の圧力が急激に上昇した場合に、配管４２の圧力を解放することができ、不均化反応による影響を軽減できる。 The air conditioner 2 includes a relief valve 60 in a pipe 42 through which the compressor 200 discharges compressed refrigerant, which releases the pressure when the pressure in the pipe 42 is equal to or higher than a set pressure.
Thereby, when the pressure in the pipe 42 suddenly increases due to the occurrence of the disproportionation reaction, the pressure in the pipe 42 can be released, and the influence of the disproportionation reaction can be reduced.
　また、空気調和装置２において、圧縮機２００は、作動媒体を吸入する吸込口１０４と、吸込口１０４から吸入された作動媒体を圧縮する第１圧縮機１００Ａと、第１圧縮機１００Ａにより圧縮された作動媒体を圧縮する第２圧縮機１００Ｂと、を含む２段圧縮機である。空気調和装置２は、第１圧縮機１００Ａと第２圧縮機１００Ｂとの間に作動媒体を供給するインジェクション部２０２を有する。
　これにより、空気調和装置２は、エチレン系フルオロオレフィンを含む作動媒体を利用することにより低ＧＷＰ化を実現できる。さらに、インジェクション部２０２により、第１圧縮機１００Ａと第２圧縮機１００Ｂとの間の接続管２０１に冷媒を供給することによって圧縮機２００の吐出冷媒の温度を低下させて、エチレン系フルオロオレフィンの不均化反応が発生しにくい構成を実現する。従って、ＧＷＰの低い冷媒を利用する場合の不均化反応を抑制できる。
　また、空気調和装置２は、２段式の圧縮機２００を用いることにより、第１圧縮機１００Ａと第２圧縮機１００Ｂのそれぞれの圧縮比を抑えることができる。このため、圧縮ロスの低減、及び、圧縮機２００の電動機の負荷の低減を図ることができ、電動機の温度の上昇を抑制することが期待できる。 In the air conditioner 2, the compressor 200 includes a suction port 104 that sucks a working medium, a first compressor 100A that compresses the working medium sucked from the suction port 104, and a first compressor 100A that compresses the working medium. This is a two-stage compressor including a second compressor 100B that compresses the working medium. The air conditioner 2 includes an injection section 202 that supplies a working medium between the first compressor 100A and the second compressor 100B.
As a result, the air conditioner 2 can achieve low GWP by using a working medium containing ethylene-based fluoroolefins. Furthermore, the injection unit 202 supplies refrigerant to the connecting pipe 201 between the first compressor 100A and the second compressor 100B, thereby lowering the temperature of the refrigerant discharged from the compressor 200. Achieve a configuration in which disproportionation reactions are less likely to occur. Therefore, disproportionation reactions can be suppressed when using a refrigerant with a low GWP.
Furthermore, by using the two-stage compressor 200, the air conditioner 2 can suppress the compression ratio of each of the first compressor 100A and the second compressor 100B. Therefore, it is possible to reduce compression loss and the load on the electric motor of the compressor 200, and it can be expected to suppress a rise in the temperature of the electric motor.
　また、制御装置２０は、空気調和装置２の暖房運転状態で高圧部における作動媒体の圧力が閾値以上まで上昇したことを検出した場合に、四方弁２１、２２を制御して暖房運転状態から冷房運転状態への切り替えを行う。これにより、暖房運転状態において高圧部で不均化反応が発生したと推定される場合に、冷房運転状態に切り替えることによって高圧の冷媒が流れる領域を制限できる。これにより、不均化反応の伝搬を抑制できる。また、冷房運転状態では利用側熱交換器である熱交換器１１ａ、１１ｂに高圧の冷媒が流れなくなるので、不均化反応の影響が被調和空間に及ぶことを回避できる。 Further, when the control device 20 detects that the pressure of the working medium in the high pressure section has increased to a threshold value or more in the heating operation state of the air conditioner 2, the control device 20 controls the four- way valves 21 and 22 to change the heating operation state to the cooling state. Switch to operating state. Thereby, when it is estimated that a disproportionation reaction has occurred in the high-pressure section in the heating operation state, the region through which the high-pressure refrigerant flows can be restricted by switching to the cooling operation state. Thereby, propagation of the disproportionation reaction can be suppressed. Further, in the cooling operation state, high-pressure refrigerant does not flow to the heat exchangers 11a and 11b, which are the utilization side heat exchangers, so that the influence of the disproportionation reaction can be avoided from reaching the conditioned space.
　さらに、空気調和装置２は、インジェクション部２０２に気液分離器１５から作動媒体を流入させる配管４３を備える。空気調和装置２は、配管４３を開閉する弁１６と、弁１６を制御する制御装置２０と、を備える。制御装置２０は、圧縮機２００の温度が予め設定された条件を満たす場合に弁１６を開かせる制御を行う。
　これにより、圧縮機２００の温度が予め設定された条件を満たす場合に、気液分離器１５から配管４３を通じて冷媒を抜き取ることにより、気液分離器１５における冷媒の圧力を低下させ、気液分離器１５で冷媒を膨張させることができる。そのため、気液分離器１５を中間冷却器として作用させ、膨張弁１４、及び、気液分離器１５において、二段階の膨張過程を構成させることができる。これにより、圧縮機２００において不均化反応が発生しやすい状態が生じた場合に、この状態を解消できる。また、圧縮機２００において不均化反応が発生したと推定される場合に、不均化反応を抑制または停止させることができる。 Furthermore, the air conditioner 2 includes a pipe 43 that allows the working medium to flow into the injection section 202 from the gas-liquid separator 15 . The air conditioner 2 includes a valve 16 that opens and closes the pipe 43 and a control device 20 that controls the valve 16. The control device 20 controls the valve 16 to be opened when the temperature of the compressor 200 satisfies preset conditions.
As a result, when the temperature of the compressor 200 satisfies preset conditions, the refrigerant is extracted from the gas-liquid separator 15 through the pipe 43, thereby reducing the pressure of the refrigerant in the gas-liquid separator 15, and separating the gas and liquid. The refrigerant can be expanded in the vessel 15. Therefore, the gas-liquid separator 15 can act as an intercooler, and a two-stage expansion process can be configured in the expansion valve 14 and the gas-liquid separator 15. This makes it possible to eliminate a situation in which a disproportionation reaction is likely to occur in the compressor 200. Furthermore, when it is estimated that a disproportionation reaction has occurred in the compressor 200, the disproportionation reaction can be suppressed or stopped.
　（実施の形態３）
　図６は、実施の形態３における空気調和装置１Ａの構成を示す図である。図６に示す空気調和装置１Ａは、本発明の冷凍回路を適用した一例である。 (Embodiment 3)
FIG. 6 is a diagram showing the configuration of an air conditioner 1A in the third embodiment. An air conditioner 1A shown in FIG. 6 is an example to which the refrigeration circuit of the present invention is applied.
　空気調和装置１Ａは、図１～図４を参照して説明した空気調和装置１に、配管５５及び弁５６を設けた構成である。配管５５及び弁５６を除く各部の構成は、実施の形態１で説明した構成と共通であるため、同じ符号を付して説明を省略する。 The air conditioner 1A has a configuration in which a pipe 55 and a valve 56 are added to the air conditioner 1 described with reference to FIGS. 1 to 4. The configuration of each part except for the piping 55 and the valve 56 is the same as the configuration described in Embodiment 1, so the same reference numerals are given and the explanation will be omitted.
　配管５５は、配管４８と、配管４１とを接続する冷媒配管である。配管５５には弁５６が設けられる。弁５６は、例えば電磁弁で構成され、制御装置１０の制御に従って開閉する。弁５６は電磁弁で構成されてもよい。この場合、制御装置１０は、弁５６の開閉に加え、弁５６の開度を調整することができる。配管５５は電動機冷却回路の一例に対応し、弁５６は電動機冷却弁の一例に対応する。 The pipe 55 is a refrigerant pipe that connects the pipe 48 and the pipe 41. A valve 56 is provided in the pipe 55. The valve 56 is composed of, for example, a solenoid valve, and opens and closes under the control of the control device 10. The valve 56 may be a solenoid valve. In this case, the control device 10 can adjust the opening degree of the valve 56 in addition to opening and closing the valve 56. Piping 55 corresponds to an example of a motor cooling circuit, and valve 56 corresponds to an example of a motor cooling valve.
　弁５６が開かれた状態で、配管５５には、配管４８から配管４１へ冷媒が流れる。配管５５を流れる冷媒は、気液分離器１５から配管４８に流れる液体の冷媒である。この冷媒は、配管４１を通って吸込口１０４に達し、容器１０２の内部に供給される。 With the valve 56 open, refrigerant flows through the pipe 55 from the pipe 48 to the pipe 41. The refrigerant flowing through the pipe 55 is a liquid refrigerant flowing from the gas-liquid separator 15 to the pipe 48 . This refrigerant passes through the pipe 41 and reaches the suction port 104, and is supplied into the container 102.
　従って、弁５６が開かれた場合、液体の冷媒が吸込口１０４から電動機１１０に供給される。この冷媒は吸込口１０４を通って圧縮機構１２０に吸い込まれる過程で、電動機１１０を冷却する。配管５５は、電動機１１０を収容する容器１０２に直接接続されてもよい。この場合も、配管５５から容器１０２に液体の冷媒が供給されることによって、電動機１１０の温度を下げることができる。特に、図２に示したように、吸込口１０４から吸い込まれた冷媒が固定子１１１と回転子１１２との間のエアギャップを通る構成では、より効果的に電動機１１０を冷却できる。 Therefore, when the valve 56 is opened, liquid refrigerant is supplied to the electric motor 110 from the suction port 104. This refrigerant cools the electric motor 110 in the process of being sucked into the compression mechanism 120 through the suction port 104. Piping 55 may be directly connected to container 102 containing electric motor 110. In this case as well, the temperature of the electric motor 110 can be lowered by supplying liquid refrigerant from the pipe 55 to the container 102. In particular, as shown in FIG. 2, in a configuration in which the refrigerant sucked in from the suction port 104 passes through the air gap between the stator 111 and the rotor 112, the electric motor 110 can be cooled more effectively.
　空気調和装置１Ａにおいて、制御装置１０は、上述した弁１６の開閉制御、及び、図４に示した制御を実行する。 In the air conditioner 1A, the control device 10 executes the opening/closing control of the valve 16 described above and the control shown in FIG. 4.
　さらに、制御装置１０は、圧縮機１００の温度が予め設定された条件を満たす場合に、弁５６を開かせる制御を行う。予め設定された条件は、例えば、圧縮機１００の温度の閾値である。具体的には、圧縮機１００の温度、または、圧縮機構１２０の吐出冷媒の温度である。制御装置１０は、電動機１１０の温度、或いは、圧縮機構１２０の吐出冷媒の温度が閾値を超えた場合に、弁５６を開かせる。制御装置１０は、弁５６を開かせることにより、電動機１１０に液体の冷媒を供給させて、電動機１１０の温度を低下させることができる。これにより、電動機１１０を冷却して不均化反応を抑制できる。 Further, the control device 10 controls the valve 56 to be opened when the temperature of the compressor 100 satisfies a preset condition. The preset condition is, for example, a temperature threshold of the compressor 100. Specifically, it is the temperature of the compressor 100 or the temperature of the refrigerant discharged from the compression mechanism 120. The control device 10 opens the valve 56 when the temperature of the electric motor 110 or the temperature of the refrigerant discharged from the compression mechanism 120 exceeds a threshold value. By opening the valve 56, the control device 10 can supply liquid refrigerant to the electric motor 110 and lower the temperature of the electric motor 110. Thereby, the electric motor 110 can be cooled and the disproportionation reaction can be suppressed.
　このように、実施の形態３の空気調和装置１Ａは、圧縮機１００の容器１０２に、配管４１を通じて液体の作動媒体を流入させる配管５５と、配管５５を開閉する弁５６と、弁５６を制御する制御装置１０と、を備える。制御装置１０は、圧縮機１００の温度が予め設定された条件を満たす場合に弁５６を開かせる制御を行う。
　これにより、電動機１１０を液体の冷媒によって冷却できる。例えば、電動機１１０が高温となって冷媒の不均化反応が発生しやすい状態となった場合、或いは、冷媒の不均化反応の発生が推定される状態となった場合に、電動機１１０を冷却できる。このため、冷媒の不均化反応を抑制または停止させることができる。 In this way, the air conditioner 1A according to the third embodiment controls the pipe 55 that allows liquid working medium to flow into the container 102 of the compressor 100 through the pipe 41, the valve 56 that opens and closes the pipe 55, and the valve 56. A control device 10 is provided. The control device 10 controls the valve 56 to be opened when the temperature of the compressor 100 satisfies preset conditions.
Thereby, the electric motor 110 can be cooled by the liquid refrigerant. For example, when the electric motor 110 reaches a high temperature and is in a state where a refrigerant disproportionation reaction is likely to occur, or when a refrigerant disproportionation reaction is estimated to occur, the electric motor 110 is cooled. can. Therefore, the disproportionation reaction of the refrigerant can be suppressed or stopped.
　（実施の形態４）
　図７は、実施の形態４における空気調和装置２Ａの構成を示す図である。図７に示す空気調和装置２Ａは、本発明の冷凍回路を適用した一例である。 (Embodiment 4)
FIG. 7 is a diagram showing the configuration of an air conditioner 2A in Embodiment 4. An air conditioner 2A shown in FIG. 7 is an example to which the refrigeration circuit of the present invention is applied.
　空気調和装置２Ａは、図５を参照して説明した空気調和装置２に、配管５７、弁５８及び弁５９を設けた構成である。配管５７、弁５８及び弁５９を除く各部の構成は、実施の形態２で説明した構成と共通であるため、同じ符号を付して説明を省略する。 The air conditioner 2A has a configuration in which the air conditioner 2 described with reference to FIG. 5 is provided with a pipe 57, a valve 58, and a valve 59. The configuration of each part other than the piping 57, valve 58, and valve 59 is the same as the configuration described in the second embodiment, so the same reference numerals are given and the explanation will be omitted.
　配管５７の一端は配管４８に接続され、気液分離器１５から配管５７に液体の冷媒が流れる。配管５７は分岐部２０５において２手に分岐する。配管５７は、接続部２０３において接続管２０１に接続され、接続部２０４において配管４１に接続される。分岐部２０５と接続部２０３との間には弁５８が設けられ、分岐部２０５と接続部２０４との間には弁５９が設けられる。 One end of the pipe 57 is connected to the pipe 48, and liquid refrigerant flows from the gas-liquid separator 15 to the pipe 57. The pipe 57 branches into two branches at a branching portion 205 . The pipe 57 is connected to the connecting pipe 201 at the connecting part 203 and to the pipe 41 at the connecting part 204. A valve 58 is provided between the branch section 205 and the connection section 203, and a valve 59 is provided between the branch section 205 and the connection section 204.
　弁５８、及び弁５９は、それぞれ、例えば電磁弁で構成され、制御装置２０の制御に従って開閉する。弁５８、５９は電磁弁で構成されてもよい。この場合、制御装置２０は、弁５８、５９の開閉に加え、弁５８及び弁５９のそれぞれの開度を調整できる。配管５７は電動機冷却回路の一例に対応し、弁５８、５９は電動機冷却弁の一例に対応する。 The valves 58 and 59 are each formed of, for example, a solenoid valve, and are opened and closed under the control of the control device 20. The valves 58 and 59 may be constituted by electromagnetic valves. In this case, the control device 20 can adjust the opening degree of each of the valves 58 and 59 in addition to opening and closing the valves 58 and 59. The pipe 57 corresponds to an example of a motor cooling circuit, and the valves 58 and 59 correspond to an example of a motor cooling valve.
　弁５８が開かれた状態では、配管５７を通じて、気液分離器１５に貯留された液体の冷媒が接続管２０１に流れる。この冷媒は第２圧縮機１００Ｂに吸い込まれ、第２圧縮機１００Ｂの内部で気化することにより、第２圧縮機１００Ｂを冷却する。 When the valve 58 is open, the liquid refrigerant stored in the gas-liquid separator 15 flows into the connecting pipe 201 through the pipe 57. This refrigerant is sucked into the second compressor 100B and vaporized inside the second compressor 100B, thereby cooling the second compressor 100B.
　弁５９が開かれた状態では、配管５７を通じて、気液分離器１５に貯留された液体の冷媒が配管４１に流れる。この冷媒は第１圧縮機１００Ａに吸い込まれ、第１圧縮機１００Ａの内部で気化することにより、第１圧縮機１００Ａを冷却する。 When the valve 59 is open, the liquid refrigerant stored in the gas-liquid separator 15 flows into the pipe 41 through the pipe 57. This refrigerant is sucked into the first compressor 100A and vaporized inside the first compressor 100A, thereby cooling the first compressor 100A.
　空気調和装置２Ａにおいて、制御装置２０は、実施の形態２で説明したように、上述した弁１６の開閉制御、及び、図４に示した制御を実行する。 In the air conditioner 2A, the control device 20 executes the opening/closing control of the valve 16 described above and the control shown in FIG. 4, as described in the second embodiment.
　さらに、制御装置２０は、圧縮機２００の温度が予め設定された条件を満たす場合に、弁５８、５９を開かせる制御を行う。予め設定された条件は、例えば、圧縮機２００の温度の閾値である。具体的には、第１圧縮機１００Ａが備える電動機、及び／または第２圧縮機１００Ｂが備える電動機の温度、或いは、第１圧縮機１００Ａ及び／または第２圧縮機１００Ｂの吐出冷媒の温度である。制御装置２０は、例えば、第２圧縮機１００Ｂの電動機の温度、或いは、第２圧縮機１００Ｂの吐出冷媒の温度が閾値を超えた場合に、弁５８を開かせる。制御装置２０は、弁５８を開かせることにより、第２圧縮機１００Ｂに液体の冷媒を吸い込ませて、第２圧縮機１００Ｂの電動機の温度及び第２圧縮機１００Ｂの吐出冷媒を低下させることができる。また、例えば、制御装置２０は、第１圧縮機１００Ａの電動機の温度、或いは、第１圧縮機１００Ａの吐出冷媒の温度が閾値を超えた場合に、弁５９を開かせる。制御装置２０は、弁５９を開かせることにより、第１圧縮機１００Ａに液体の冷媒を吸い込ませて、第１圧縮機１００Ａの電動機の温度及び第１圧縮機１００Ａの吐出冷媒を低下させることができる。これにより、圧縮機２００を冷却して不均化反応を抑制または防止できる。 Further, the control device 20 controls the valves 58 and 59 to be opened when the temperature of the compressor 200 satisfies preset conditions. The preset condition is, for example, a temperature threshold of the compressor 200. Specifically, it is the temperature of the electric motor included in the first compressor 100A and/or the electric motor included in the second compressor 100B, or the temperature of the refrigerant discharged from the first compressor 100A and/or the second compressor 100B. . For example, the control device 20 opens the valve 58 when the temperature of the electric motor of the second compressor 100B or the temperature of the refrigerant discharged from the second compressor 100B exceeds a threshold value. By opening the valve 58, the control device 20 can cause the second compressor 100B to suck liquid refrigerant, thereby lowering the temperature of the electric motor of the second compressor 100B and the refrigerant discharged from the second compressor 100B. can. For example, the control device 20 opens the valve 59 when the temperature of the electric motor of the first compressor 100A or the temperature of the refrigerant discharged from the first compressor 100A exceeds a threshold value. By opening the valve 59, the control device 20 can cause the first compressor 100A to suck liquid refrigerant, thereby lowering the temperature of the electric motor of the first compressor 100A and the refrigerant discharged from the first compressor 100A. can. Thereby, the compressor 200 can be cooled to suppress or prevent the disproportionation reaction.
　このように、実施の形態４の空気調和装置２Ａは、圧縮機２００に、配管４３を通じて液体の作動媒体を流入させる配管５７と、配管５７を開閉する弁５８、５９と、弁５８、５９を制御する制御装置２０と、を備える。制御装置２０は、圧縮機２００の温度が予め設定された条件を満たす場合に弁５８、５９を開かせる制御を行う。
　これにより、配管４３を通じて圧縮機２００に冷媒を流入させることにより、圧縮機２００を冷却できる。例えば、第１圧縮機１００Ａまたは第２圧縮機１００Ｂの電動機が高温となって冷媒の不均化反応が発生しやすい状態となった場合、或いは、冷媒の不均化反応の発生が推定される状態となった場合に、電動機を冷却できる。このため、冷媒の不均化反応を抑制または停止させることができる。 In this way, the air conditioner 2A of the fourth embodiment includes the pipe 57 that allows liquid working medium to flow into the compressor 200 through the pipe 43, the valves 58 and 59 that open and close the pipe 57, and the valves 58 and 59. and a control device 20 for controlling. The control device 20 controls the valves 58 and 59 to be opened when the temperature of the compressor 200 satisfies preset conditions.
Thereby, the compressor 200 can be cooled by allowing the refrigerant to flow into the compressor 200 through the pipe 43. For example, if the electric motor of the first compressor 100A or the second compressor 100B reaches a high temperature and is in a state where a refrigerant disproportionation reaction is likely to occur, or it is estimated that a refrigerant disproportionation reaction is likely to occur. If this occurs, the motor can be cooled down. Therefore, the disproportionation reaction of the refrigerant can be suppressed or stopped.
　（実施の形態５）
　図８は、実施の形態５における空気調和装置３の構成を示す図である。図８に示す空気調和装置３は、本発明の冷凍回路を適用した一例である。 (Embodiment 5)
FIG. 8 is a diagram showing the configuration of the air conditioner 3 in the fifth embodiment. The air conditioner 3 shown in FIG. 8 is an example to which the refrigeration circuit of the present invention is applied.
　空気調和装置３は、図１～図４を参照して説明した空気調和装置１の一部と共通する構成を有する。これらの共通の構成について、実施の形態１と同じ符号を付して説明を省略する。 The air conditioner 3 has a configuration common to a part of the air conditioner 1 described with reference to FIGS. 1 to 4. These common configurations are given the same reference numerals as those in Embodiment 1, and a description thereof will be omitted.
　本開示は、上述した実施の形態１～４の空気調和装置１、１Ａ、２、２Ａに限らず、冷房運転と暖房運転とを切り替えて実行可能な冷凍装置に適用可能である。空気調和装置３は、この種の冷凍装置の一例に対応する。 The present disclosure is applicable not only to the air conditioners 1, 1A, 2, and 2A of Embodiments 1 to 4 described above, but also to a refrigeration system that can switch between cooling operation and heating operation. The air conditioner 3 corresponds to an example of this type of refrigeration device.
　空気調和装置３は、利用側熱交換器としての熱交換器１１ａ、１１ｂと、熱交換器１１ａ、１１ｂに繋がる配管に設けられた膨張弁１２ａ、１２ｂと、熱源側熱交換器としての熱交換器１３と、熱交換器１３に繋がる配管４７に設けられた膨張弁１４と、を備える。また、空気調和装置３は、圧縮機１００と、熱交換器１１ａ、１１ｂまたは熱交換器１３を切り替えて圧縮機１００の吐出側の配管４２に接続する四方弁２１と、を備える。 The air conditioner 3 includes heat exchangers 11a and 11b as usage side heat exchangers, expansion valves 12a and 12b provided in piping connected to the heat exchangers 11a and 11b, and a heat exchanger as a heat source side heat exchanger. 13 and an expansion valve 14 provided in a pipe 47 connected to the heat exchanger 13. The air conditioner 3 also includes a compressor 100 and a four-way valve 21 that switches between the heat exchangers 11a, 11b or the heat exchanger 13 and connects to the piping 42 on the discharge side of the compressor 100.
　空気調和装置３は、四方弁２１を制御する制御装置１０Ａを備える。制御装置１０Ａは、制御装置１０と同様に、マイクロコントローラ等のプロセッサを備える。制御装置１０Ａは、プロセッサによりプログラムを実行することにより、或いは、プログラムされたハードウェアの機能により空気調和装置３を制御する。制御装置１０Ａは、四方弁２１を制御して、冷房運転状態と暖房運転状態とを切り替える。 The air conditioner 3 includes a control device 10A that controls the four-way valve 21. The control device 10A, like the control device 10, includes a processor such as a microcontroller. The control device 10A controls the air conditioner 3 by executing a program using a processor or by using programmed hardware functions. The control device 10A controls the four-way valve 21 to switch between a cooling operation state and a heating operation state.
　すなわち、制御装置１０Ａは、四方弁２１によって、圧縮機１００が高圧の冷媒を吐出する配管４２と、熱交換器１３に繋がる配管４６とを接続し、熱交換器１１ａ、１１ｂに繋がる配管４４と圧縮機１００の吸い込み側の配管４１とを接続する。これにより、空気調和装置３は、冷房運転を実行する。冷房運転状態で、圧縮機１００が吐出する高圧の冷媒が熱交換器１３において凝縮され、膨張弁１２ａ、１２ｂを経由して熱交換器１１ａ、１１ｂに送られる。この冷媒は膨張弁１２ａ、１２ｂにより減圧されて熱交換器１１ａ、１１ｂで蒸発し、配管４１を通って圧縮機１００に吸い込まれる。図８には空気調和装置３の冷房運転状態を示す。冷房運転状態において、高圧部ＨＰは、例えば、圧縮機１００、高圧の冷媒が流れる配管４２、四方弁２１、及び、熱交換器１３を含む。 That is, the control device 10A uses the four-way valve 21 to connect a pipe 42 through which the compressor 100 discharges high-pressure refrigerant to a pipe 46 connected to the heat exchanger 13, and a pipe 44 connected to the heat exchangers 11a and 11b. It is connected to the suction side piping 41 of the compressor 100. Thereby, the air conditioner 3 executes the cooling operation. During cooling operation, high-pressure refrigerant discharged from the compressor 100 is condensed in the heat exchanger 13 and sent to the heat exchangers 11a and 11b via the expansion valves 12a and 12b. This refrigerant is depressurized by the expansion valves 12a, 12b, evaporated in the heat exchangers 11a, 11b, and is sucked into the compressor 100 through the pipe 41. FIG. 8 shows the cooling operation state of the air conditioner 3. In the cooling operation state, the high pressure section HP includes, for example, a compressor 100, a pipe 42 through which a high pressure refrigerant flows, a four-way valve 21, and a heat exchanger 13.
　空気調和装置３が制御装置１０Ａの制御により暖房運転を実行する場合、圧縮機１００が吐出する高圧の冷媒が熱交換器１１ａ、１１ｂにおいて凝縮され、膨張弁１４を経由して熱交換器１３に送られる。この冷媒は膨張弁１４により減圧されて熱交換器１３で蒸発し、配管４１を通って圧縮機１００に吸い込まれる。空気調和装置３の暖房運転状態において、図示はしないが、領域ＨＰは、圧縮機１００、配管４２、四方弁２１、及び、熱交換器１１ａ、１１ｂを含む。 When the air conditioner 3 performs heating operation under the control of the control device 10A, the high-pressure refrigerant discharged by the compressor 100 is condensed in the heat exchangers 11a and 11b, and is transferred to the heat exchanger 13 via the expansion valve 14. Sent. This refrigerant is depressurized by the expansion valve 14, evaporated in the heat exchanger 13, and sucked into the compressor 100 through the pipe 41. In the heating operation state of the air conditioner 3, although not shown, the region HP includes the compressor 100, the piping 42, the four-way valve 21, and the heat exchangers 11a and 11b.
　このように、空気調和装置３は、制御装置１０Ａの制御により、熱交換器１３を凝縮器として動作させる冷房運転と、熱交換器１１ａ、１１ｂを凝縮器とし熱交換器１３を蒸発器として動作させる暖房運転とを、四方弁２１によって切り替え可能な冷凍装置である。 Thus, under the control of the control device 10A, the air conditioner 3 performs a cooling operation in which the heat exchanger 13 is operated as a condenser, and a cooling operation in which the heat exchanger 11a and 11b are operated as a condenser and the heat exchanger 13 is operated as an evaporator. This is a refrigeration system that can switch between heating operation and heating operation using a four-way valve 21.
　空気調和装置３は、電動機１１０の温度を検出する不図示の温度センサ、及び、圧縮機構１２０が吐出する冷媒の温度を検出する不図示の温度センサのいずれか１以上を備えてもよい。これらの温度センサは制御装置１０Ａに接続される。制御装置１０Ａは、温度センサの検出値を取得することにより、電動機１１０の温度、及び、圧縮機構１２０が吐出する冷媒の温度のいずれか、或いは両方を検出する。また、制御装置１０Ａは、圧縮機構１２０が吐出する冷媒の温度に基づいて、圧縮機構１２０が吐出する冷媒の圧力を算出してもよい。空気調和装置３は、圧縮機構１２０が吐出する冷媒の圧力を検出する圧力センサを備えてもよい。また、空気調和装置３は、熱交換器１１ａ、１１ｂ、及び、熱交換器１３の温度を検出する不図示の熱交換器温度センサを備えてもよい。この場合、制御装置１０Ａは、熱交換器温度センサの検出値に基づいて、圧縮機構１２０が吐出する冷媒の圧力や温度を算出してもよく、上述した温度センサを備えていない構成としてもよい。 The air conditioner 3 may include one or more of a temperature sensor (not shown) that detects the temperature of the electric motor 110 and a temperature sensor (not shown) that detects the temperature of the refrigerant discharged by the compression mechanism 120. These temperature sensors are connected to the control device 10A. The control device 10A detects either or both of the temperature of the electric motor 110 and the temperature of the refrigerant discharged by the compression mechanism 120 by acquiring the detected value of the temperature sensor. Further, the control device 10A may calculate the pressure of the refrigerant discharged by the compression mechanism 120 based on the temperature of the refrigerant discharged by the compression mechanism 120. The air conditioner 3 may include a pressure sensor that detects the pressure of the refrigerant discharged by the compression mechanism 120. Furthermore, the air conditioner 3 may include a heat exchanger temperature sensor (not shown) that detects the temperatures of the heat exchangers 11a, 11b and the heat exchanger 13. In this case, the control device 10A may calculate the pressure and temperature of the refrigerant discharged by the compression mechanism 120 based on the detected value of the heat exchanger temperature sensor, or may be configured without the temperature sensor described above. .
　制御装置１０Ａは、制御装置１０と同様に図４に示した制御を実行する。すなわち、制御装置１０Ａは、空気調和装置３の暖房運転中に高圧部ＨＰにおける冷媒の圧力が閾値以上まで上昇したことを検出した場合に、空気調和装置３を冷房運転に切り替えさせる。 The control device 10A executes the control shown in FIG. 4 similarly to the control device 10. That is, when the control device 10A detects that the pressure of the refrigerant in the high pressure portion HP has increased to a threshold value or more during the heating operation of the air conditioner 3, the control device 10A switches the air conditioner 3 to the cooling operation.
　このように、空気調和装置３は、圧縮機１００と、熱源側熱交換器である熱交換器１３と、利用側熱交換器である熱交換器１１ａ、１１ｂと、膨張機構と、を備える。空気調和装置３は、熱交換器１１ａ、１１ｂを凝縮器として動作させる暖房運転状態と、熱交換器１３を凝縮器として動作させる冷房運転状態と、を切り替える四方弁２１と、制御装置１０Ａと、を備える。空気調和装置３は、冷媒として、エチレン系フルオロオレフィンを含む作動媒体を使用する。制御装置１０Ａは、暖房運転状態で圧縮機１００と凝縮器とを含む高圧部における作動媒体の圧力が閾値以上まで上昇したことを検出した場合に、四方弁２１を制御して暖房運転状態から冷房運転状態への切り替えを行う。
　これにより、空気調和装置３は、エチレン系フルオロオレフィンを含む作動媒体を利用することにより低ＧＷＰ化を実現できる。さらに、空気調和装置３は、冷媒の不均化反応が発生した可能性がある場合、或いは、不均化反応が発生したと推定される場合に、空気調和装置３を暖房運転状態から冷房運転状態に切り替えて、高圧の冷媒が流れる領域ＨＰを狭くする。これにより、不均化反応によって冷媒の圧力が急激に上昇する領域ＨＰを限定することができ、冷凍サイクルにおける不均化反応の影響を抑えることができる。例えば、熱交換器１１ａ、１１ｂが空気調和装置３の被調和空間またはその近傍に設置される場合、制御装置１０Ａの制御により、不均化反応の影響が被調和空間に及ぶことを防止または抑制できる。 In this way, the air conditioner 3 includes the compressor 100, the heat exchanger 13 which is a heat source side heat exchanger, the heat exchangers 11a and 11b which are usage side heat exchangers, and an expansion mechanism. The air conditioner 3 includes a four-way valve 21 that switches between a heating operation state in which the heat exchangers 11a and 11b operate as a condenser and a cooling operation state in which the heat exchanger 13 operates as a condenser, and a control device 10A. Equipped with The air conditioner 3 uses a working medium containing ethylene-based fluoroolefin as a refrigerant. When the control device 10A detects that the pressure of the working medium in the high-pressure section including the compressor 100 and the condenser has increased to a threshold value or more in the heating operation state, the control device 10A controls the four-way valve 21 to switch from the heating operation state to the cooling state. Switch to operating state.
Thereby, the air conditioner 3 can realize a low GWP by using a working medium containing ethylene-based fluoroolefin. Further, the air conditioner 3 switches the air conditioner 3 from the heating operation state to the cooling operation when there is a possibility that a refrigerant disproportionation reaction has occurred, or when it is estimated that a disproportionation reaction has occurred. state to narrow the region HP through which high-pressure refrigerant flows. Thereby, the region HP where the pressure of the refrigerant rapidly increases due to the disproportionation reaction can be limited, and the influence of the disproportionation reaction on the refrigeration cycle can be suppressed. For example, when the heat exchangers 11a and 11b are installed in or near the conditioned space of the air conditioner 3, the control of the control device 10A prevents or suppresses the influence of the disproportionation reaction from reaching the conditioned space. can.
　膨張機構は、凝縮器の出口に配置された膨張弁１４または膨張弁１２ａ、１２ｂを含む。空気調和装置３は、膨張弁１２ａ、１２ｂ、１４を制御する制御装置１０Ａを備える。制御装置１０Ａは、空気調和装置３の高圧部における作動媒体の圧力が閾値以上まで上昇したことを検出した場合に、膨張弁１２ａ、１２ｂ、１４のいずれかを第１開度まで閉方向に動作させ、その後、高圧部における作動媒体の圧力の上昇が停止した場合に膨張弁を第２開度まで閉方向に動作させる。第２開度は、例えば、全閉の状態である。高圧部は、例えば、圧縮機１００と凝縮器とを含む。
　これにより、冷媒の不均化反応が発生した可能性がある場合、或いは、不均化反応が発生したと推定される場合に、不均化反応に伴う圧力上昇を抑制できる。そして、高圧部の圧力の上昇が停止した後に、弁を第２開度まで閉じることによって、不均化反応の伝搬をより確実に抑制できる。 The expansion mechanism includes an expansion valve 14 or expansion valves 12a, 12b located at the outlet of the condenser. The air conditioner 3 includes a control device 10A that controls the expansion valves 12a, 12b, and 14. The control device 10A operates one of the expansion valves 12a, 12b, and 14 in the closing direction to a first opening degree when it is detected that the pressure of the working medium in the high-pressure part of the air conditioner 3 has increased to a threshold value or more. Then, when the pressure of the working medium in the high pressure section stops increasing, the expansion valve is operated in the closing direction to the second opening degree. The second opening degree is, for example, a fully closed state. The high pressure section includes, for example, a compressor 100 and a condenser.
Thereby, when there is a possibility that a disproportionation reaction of the refrigerant has occurred, or when it is estimated that a disproportionation reaction has occurred, it is possible to suppress the pressure increase associated with the disproportionation reaction. Then, by closing the valve to the second opening degree after the pressure rise in the high-pressure section has stopped, propagation of the disproportionation reaction can be suppressed more reliably.
　空気調和装置３においても、空気調和装置１と同様に、圧縮機１００が圧縮された冷媒を吐出する配管４２に、配管４２の圧力が設定圧以上の場合に圧力を開放するリリーフバルブ６０を設けてもよい。この場合、不均化反応が発生することに伴って配管４２の圧力が急激に上昇した場合に、配管４２の圧力を解放することができ、不均化反応による影響を軽減できる。 In the air conditioner 3, as in the air conditioner 1, the pipe 42 through which the compressor 100 discharges the compressed refrigerant is provided with a relief valve 60 that releases the pressure when the pressure in the pipe 42 is equal to or higher than the set pressure. You can. In this case, when the pressure in the pipe 42 suddenly increases due to the occurrence of the disproportionation reaction, the pressure in the pipe 42 can be released, and the influence of the disproportionation reaction can be reduced.
　（他の実施例）
　以上のように、本出願において開示する例示として、上記実施形態を説明した。しかしながら、本開示における技術は、これに限定されず、変更、置き換え、付加、省略などを行った実施形態にも適用できる。また、上記実施形態で説明した各構成要素を組み合わせて、新たな実施形態とすることも可能である。
　そこで、以下、他の実施形態を例示する。 (Other examples)
As mentioned above, the above embodiment has been described as an example disclosed in this application. However, the technology in the present disclosure is not limited to this, and can also be applied to embodiments in which changes, replacements, additions, omissions, etc. are made. Furthermore, it is also possible to create a new embodiment by combining the components described in the above embodiments.
Therefore, other embodiments will be illustrated below.
　上述した実施形態では、配管４２に設けられる圧力解放手段として、オーバーフローバルブとも呼ばれるリリーフバルブ６０を用いる構成を例示したが、これは一例である。圧力解放手段は、配管４２の圧力が設定圧以上の場合に破壊されて圧力を解放する、破裂板（ラプチャーディスク）であってもよい。
　上述した実施形態における圧縮機１００、第１圧縮機１００Ａ、及び第２圧縮機１００Ｂは、スクロール式の圧縮機に限定されず、ロータリー式の圧縮機であってもよいし、レシプロ式の圧縮機であってもよい。 In the embodiment described above, a configuration is illustrated in which the relief valve 60, also called an overflow valve, is used as the pressure release means provided in the pipe 42, but this is just an example. The pressure release means may be a rupture disk that ruptures to release the pressure when the pressure in the pipe 42 exceeds a set pressure.
The compressor 100, the first compressor 100A, and the second compressor 100B in the embodiments described above are not limited to scroll compressors, but may be rotary compressors, or reciprocating compressors. It may be.
　空気調和装置１、１Ａ、２、２Ａが備える各種のセンサの構成は任意である。例えば、空気調和装置１は、熱交換器１１ａ、１１ｂ、１３の温度を検出する温度センサを備えてもよく、空気調和装置１Ａ、２、２Ａにおいても同様である。また、空気調和装置１、１Ａは、圧縮機１００が吐出する冷媒の温度を検出する冷媒温度センサを備えてもよい。また、空気調和装置２、２Ａは、圧縮機２００が吐出する冷媒の温度を検出する冷媒温度センサを備えてもよい。これらのセンサは制御装置１０、２０に適宜に接続され、制御装置１０、２０がセンサの検出値を取得可能であればよい。 The configurations of the various sensors included in the air conditioners 1, 1A, 2, and 2A are arbitrary. For example, the air conditioner 1 may include a temperature sensor that detects the temperature of the heat exchangers 11a, 11b, and 13, and the same applies to the air conditioners 1A, 2, and 2A. Furthermore, the air conditioners 1 and 1A may include a refrigerant temperature sensor that detects the temperature of the refrigerant discharged by the compressor 100. Furthermore, the air conditioners 2 and 2A may include a refrigerant temperature sensor that detects the temperature of the refrigerant discharged by the compressor 200. These sensors may be connected to the control devices 10, 20 as appropriate so that the control devices 10, 20 can acquire the detected values of the sensors.
　（上記実施形態によりサポートされる構成）
　上記実施形態は、以下の構成をサポートする。 (Configuration supported by the above embodiment)
The above embodiment supports the following configurations.
　（付記） (Additional note)
　（技術１）圧縮機と、熱源側熱交換器と、利用側熱交換器と、膨張機構と、前記利用側熱交換器を凝縮器として動作させる暖房運転状態と、前記熱源側熱交換器を凝縮器として動作させる冷房運転状態と、を切り替える切替弁と、制御装置と、を備え、冷媒として、エチレン系フルオロオレフィンを含む作動媒体を使用し、前記制御装置は、前記暖房運転状態で前記圧縮機と前記凝縮器とを含む高圧部における前記作動媒体の圧力が閾値以上まで上昇したことを検出した場合に、前記切替弁を制御して前記暖房運転状態から前記冷房運転状態への切り替えを行うこと、を特徴とする冷凍装置。 (Technology 1) A compressor, a heat source side heat exchanger, a user side heat exchanger, an expansion mechanism, a heating operation state in which the user side heat exchanger operates as a condenser, and a heating operation state in which the heat source side heat exchanger is operated as a condenser. a switching valve that switches between a cooling operation state in which the condenser is operated and a control device; the control device uses a working medium containing ethylene-based fluoroolefin as a refrigerant; When it is detected that the pressure of the working medium in the high-pressure section including the air conditioner and the condenser has increased to a threshold value or more, the switching valve is controlled to switch from the heating operation state to the cooling operation state. A refrigeration device characterized by the following.
　（技術２）前記膨張機構は前記凝縮器の出口に配置された膨張弁を含み、前記制御装置は、前記圧縮機と前記凝縮器とを含む高圧部における前記作動媒体の圧力が閾値以上まで上昇したことを検出した場合に、前記膨張弁を第１開度まで閉方向に動作させ、その後、前記高圧部における前記作動媒体の圧力の上昇が停止した場合に前記膨張弁を第２開度まで閉方向に動作させること、を特徴とする技術１に記載の冷凍装置。 (Technology 2) The expansion mechanism includes an expansion valve disposed at the outlet of the condenser, and the control device causes the pressure of the working medium in a high-pressure section including the compressor and the condenser to rise to a threshold value or more. the expansion valve is operated in the closing direction to a first opening degree, and then, when the pressure of the working medium in the high pressure section stops increasing, the expansion valve is operated to a second opening degree. The refrigeration device according to technique 1, characterized in that the refrigeration device is operated in a closing direction.
　（技術３）前記圧縮機が圧縮された冷媒を吐出する吐出配管に、前記吐出配管の圧力が設定圧以上の場合に圧力を開放する圧力解放手段を有すること、を特徴とする技術１または技術２に記載の冷凍装置。 (Technique 3) Technique 1 or technique characterized in that the discharge piping through which the compressor discharges the compressed refrigerant has a pressure release means that releases the pressure when the pressure of the discharge piping is equal to or higher than a set pressure. 2. The refrigeration device according to 2.
　以上のように、本発明に係る冷凍装置は、被調和空間の冷房および暖房を行う空気調和装置、冷却と加熱とを切り替える機能を有する冷蔵庫や冷凍庫を含む冷蔵装置、これらを結合した冷凍システム、及び、その他の用途に利用可能である。 As described above, the refrigeration system according to the present invention includes an air conditioner that cools and heats a space to be conditioned, a refrigeration system that includes a refrigerator or a freezer that has the function of switching between cooling and heating, and a refrigeration system that combines these. It can also be used for other purposes.
　１、１Ａ、２、２Ａ、３　空気調和装置（冷凍装置）
　１０、１０Ａ、２０　制御装置
　１１ａ、１１ｂ　熱交換器（利用側熱交換器）
　１２ａ、１２ｂ　膨張弁
　１３　熱交換器（熱源側熱交換器）
　１４　膨張弁
　１５　気液分離器（冷媒貯留部）
　１６　弁
　２０　制御装置
　２１、２２　四方弁（切替弁）
　４１　配管（吸入配管）
　４２　配管（吐出配管）
　４３　配管（冷媒配管）
　４４、４５、４６、４７、４８、４９　配管
　５５、５７　配管（電動機冷却回路）
　５６、５８、５９　弁（電動機冷却弁）
　６０　リリーフバルブ（圧力解放手段）
　１００、２００　圧縮機
　１０２　容器
　１０３　クランク軸
　１０４　吸込口（吸入部）
　１０５　吐出管
　１０７、１０８　軸受
　１１０　電動機
　１１１　固定子
　１１２　回転子
　１１６　駆動回路
　１２０　圧縮機構
　１２５　インジェクション部（冷媒供給部）
　１００Ａ　第１圧縮機（第１圧縮機構）
　１００Ｂ　第２圧縮機（第２圧縮機構）
　２０１　接続管
　２０２　インジェクション部（冷媒供給部）
　２０３　接続部
　２０４　接続部
　２０５　分岐部 1, 1A, 2, 2A, 3 Air conditioning equipment (refrigeration equipment)
10, 10A, 20 Control device 11a, 11b Heat exchanger (user side heat exchanger)
12a, 12b expansion valve 13 heat exchanger (heat source side heat exchanger)
14 Expansion valve 15 Gas-liquid separator (refrigerant storage section)
16 Valve 20 Control device 21, 22 Four-way valve (switching valve)
41 Piping (suction piping)
42 Piping (discharge piping)
43 Piping (refrigerant piping)
44, 45, 46, 47, 48, 49 Piping 55, 57 Piping (motor cooling circuit)
56, 58, 59 valves (motor cooling valve)
60 Relief valve (pressure release means)
100, 200 compressor 102 container 103 crankshaft 104 suction port (suction part)
105 discharge pipe 107, 108 bearing 110 electric motor 111 stator 112 rotor 116 drive circuit 120 compression mechanism 125 injection section (refrigerant supply section)
100A 1st compressor (1st compression mechanism)
100B Second compressor (second compression mechanism)
201 Connection pipe 202 Injection part (refrigerant supply part)
203 Connection part 204 Connection part 205 Branch part

Claims (3)

  1. 　圧縮機と、熱源側熱交換器と、利用側熱交換器と、膨張機構と、前記利用側熱交換器を凝縮器として動作させる暖房運転状態と、前記熱源側熱交換器を凝縮器として動作させる冷房運転状態と、を切り替える切替弁と、制御装置と、を備え、
    　冷媒として、エチレン系フルオロオレフィンを含む作動媒体を使用し、
    　前記制御装置は、前記暖房運転状態で前記圧縮機と前記凝縮器とを含む高圧部における前記作動媒体の圧力が閾値以上まで上昇したことを検出した場合に、前記切替弁を制御して前記暖房運転状態から前記冷房運転状態への切り替えを行うこと、を特徴とする冷凍装置。     a compressor, a heat source side heat exchanger, a usage side heat exchanger, an expansion mechanism, a heating operation state in which the usage side heat exchanger operates as a condenser, and a heating operation state in which the heat source side heat exchanger operates as a condenser. a switching valve for switching between a cooling operation state and a control device;
    Using a working medium containing ethylene-based fluoroolefins as a refrigerant,
    The control device controls the switching valve to switch off the heating when it is detected that the pressure of the working medium in the high-pressure section including the compressor and the condenser has increased to a threshold value or more in the heating operation state. A refrigeration system characterized by switching from an operating state to the cooling operating state.
  2. 　前記膨張機構は前記凝縮器の出口に配置された膨張弁を含み、
    　前記制御装置は、前記圧縮機と前記凝縮器とを含む高圧部における前記作動媒体の圧力が閾値以上まで上昇したことを検出した場合に、前記膨張弁を第１開度まで閉方向に動作させ、その後、前記高圧部における前記作動媒体の圧力の上昇が停止した場合に前記膨張弁を第２開度まで閉方向に動作させること、を特徴とする請求項１に記載の冷凍装置。     the expansion mechanism includes an expansion valve located at the outlet of the condenser;
    The control device operates the expansion valve in a closing direction to a first opening degree when detecting that the pressure of the working medium in a high-pressure section including the compressor and the condenser has increased to a threshold value or more. 2. The refrigeration system according to claim 1, further comprising operating the expansion valve in the closing direction to a second opening degree when the pressure of the working medium in the high pressure section stops increasing.
  3. 　前記圧縮機が圧縮された冷媒を吐出する吐出配管に、前記吐出配管の圧力が設定圧以上の場合に圧力を開放する圧力解放手段を有すること、を特徴とする請求項１または請求項２に記載の冷凍装置。 Claim 1 or Claim 2, characterized in that a discharge pipe through which the compressor discharges the compressed refrigerant has a pressure release means for releasing the pressure when the pressure of the discharge pipe is equal to or higher than a set pressure. Refrigeration equipment as described.
PCT/JP2023/015550 2022-04-28 2023-04-19 Refrigeration device WO2023210457A1 (en)

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS4846771A (en) * 1971-10-13 1973-07-03
JPS6317362A (en) * 1986-07-10 1988-01-25 三菱電機株式会社 Air conditioner
JPH08159621A (en) * 1994-12-08 1996-06-21 Hitachi Ltd Air conditioner
JP2009058146A (en) * 2007-08-30 2009-03-19 Sanden Corp Refrigerating air-conditioning device
JP2009092353A (en) * 2007-10-12 2009-04-30 Hitachi Appliances Inc Air conditioner
JP2019194310A (en) * 2018-04-25 2019-11-07 ダイキン工業株式会社 Composition containing coolant, heat transfer medium and heat cycle system
JP2021055983A (en) * 2019-09-30 2021-04-08 ダイキン工業株式会社 Heat source unit and refrigerating device

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS4846771A (en) * 1971-10-13 1973-07-03
JPS6317362A (en) * 1986-07-10 1988-01-25 三菱電機株式会社 Air conditioner
JPH08159621A (en) * 1994-12-08 1996-06-21 Hitachi Ltd Air conditioner
JP2009058146A (en) * 2007-08-30 2009-03-19 Sanden Corp Refrigerating air-conditioning device
JP2009092353A (en) * 2007-10-12 2009-04-30 Hitachi Appliances Inc Air conditioner
JP2019194310A (en) * 2018-04-25 2019-11-07 ダイキン工業株式会社 Composition containing coolant, heat transfer medium and heat cycle system
JP2021055983A (en) * 2019-09-30 2021-04-08 ダイキン工業株式会社 Heat source unit and refrigerating device

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