WO2023012891A1 - Dispositif à cycle de réfrigération - Google Patents

Dispositif à cycle de réfrigération Download PDF

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Publication number
WO2023012891A1
WO2023012891A1 PCT/JP2021/028744 JP2021028744W WO2023012891A1 WO 2023012891 A1 WO2023012891 A1 WO 2023012891A1 JP 2021028744 W JP2021028744 W JP 2021028744W WO 2023012891 A1 WO2023012891 A1 WO 2023012891A1
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Prior art keywords
pipe
valve
hexagonal
refrigerant
port
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PCT/JP2021/028744
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English (en)
Japanese (ja)
Inventor
千歳 田中
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三菱電機株式会社
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Application filed by 三菱電機株式会社 filed Critical 三菱電機株式会社
Priority to CN202180100966.0A priority Critical patent/CN117716187A/zh
Priority to EP21952721.5A priority patent/EP4382834A1/fr
Priority to JP2023539414A priority patent/JPWO2023012891A1/ja
Priority to PCT/JP2021/028744 priority patent/WO2023012891A1/fr
Publication of WO2023012891A1 publication Critical patent/WO2023012891A1/fr

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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
    • F25B13/00—Compression machines, plants or systems, with 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
    • F25B2313/00—Compression machines, plants or systems with reversible cycle not otherwise provided for
    • F25B2313/007—Compression machines, plants or systems with reversible cycle not otherwise provided for three pipes connecting the outdoor side to the indoor side with multiple indoor units
    • 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
    • F25B2313/00—Compression machines, plants or systems with reversible cycle not otherwise provided for
    • F25B2313/023—Compression machines, plants or systems with reversible cycle not otherwise provided for using multiple indoor units
    • F25B2313/0231—Compression machines, plants or systems with reversible cycle not otherwise provided for using multiple indoor units with simultaneous cooling and heating
    • 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
    • F25B2313/00—Compression machines, plants or systems with reversible cycle not otherwise provided for
    • F25B2313/027—Compression machines, plants or systems with reversible cycle not otherwise provided for characterised by the reversing means
    • F25B2313/0272—Compression machines, plants or systems with reversible cycle not otherwise provided for characterised by the reversing means using bridge circuits of one-way valves
    • 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
    • F25B2313/00—Compression machines, plants or systems with reversible cycle not otherwise provided for
    • F25B2313/027—Compression machines, plants or systems with reversible cycle not otherwise provided for characterised by the reversing means
    • F25B2313/0276—Compression machines, plants or systems with reversible cycle not otherwise provided for characterised by the reversing means using six-way valves
    • 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
    • F25B2400/00—General features or devices for refrigeration machines, plants or systems, combined heating and refrigeration systems or heat-pump systems, i.e. not limited to a particular subgroup of F25B
    • F25B2400/13—Economisers
    • 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
    • F25B41/00—Fluid-circulation arrangements
    • F25B41/20—Disposition of valves, e.g. of on-off valves or flow control valves

Definitions

  • the present disclosure relates to a refrigeration cycle device.
  • a refrigeration cycle device in which a plurality of indoor units are connected to an outdoor unit via a relay unit (branch unit).
  • each of a plurality of indoor units can select cooling/heating independently of the cooling/heating operation states of other indoor units.
  • cooling is required in general offices, but cooling may be required in rooms that generate heat, such as computer rooms or kitchens.
  • air conditioning for cooling and heating of separate rooms can be performed simultaneously with a single refrigeration cycle device.
  • This air conditioning system is generally called a simultaneous cooling and heating air conditioning system.
  • Patent Document 1 JP-A-2011-112233 (Patent Document 1), in a configuration using two solenoid valves and two check valves as a switching mechanism between cooling operation and heating operation of each indoor unit, the number of parts is increased. There is a problem that many of them are expensive and require a large installation space.
  • the present disclosure has been made to describe an embodiment for solving the above problems.
  • a refrigeration cycle apparatus includes a heat source unit having a compressor and an outdoor heat exchanger, a plurality of indoor units, and a repeater connected between the heat source unit and the plurality of indoor units to relay refrigerant.
  • the repeater includes a first pipe through which the refrigerant sent from the heat source unit passes, a second pipe through which the refrigerant returning to the heat source unit passes, a third pipe, a fourth pipe, the first pipe and the third pipe. a first expansion valve provided between, a second expansion valve provided between the fourth pipe and the second pipe, and a plurality of hexagonal valves provided corresponding to each of the plurality of indoor units.
  • Each of the plurality of hexagonal valves has a first port connected to the second pipe, a second port connected to one end of the refrigerant channel of the corresponding indoor unit, and a third port connected to the first pipe. , a fourth port connected to the fourth pipe, a fifth port connected to the other end of the refrigerant flow path of the corresponding indoor unit, a sixth port connected to the third pipe, the first to the It has a housing having 6 ports, and a valve body arranged inside the housing and forming a first flow path and a second flow path. The valve body is configured to switch the communication state of each of the plurality of hexagonal valves between a first switching state and a second switching state.
  • the first flow path communicates the first port and the second port
  • the second flow path communicates the fourth port and the fifth port.
  • the 3rd port and the 6th port are closed.
  • the first flow passage communicates the second port and the third port
  • the second flow passage communicates the fifth port and the sixth port. At this time, the first port and the fourth port are closed.
  • a refrigerating cycle device that is lower in cost and more compact than using a six-way valve for the cooling/heating switching mechanism of the indoor unit and using two solenoid valves and two check valves can be realized. .
  • FIG. 2 is a refrigerant circuit diagram showing a refrigerant circuit configuration of the refrigeration cycle device 300 of Embodiment 1.
  • FIG. FIG. 2 is a diagram representatively showing one indoor unit and one hexagonal valve (rotary type) corresponding thereto.
  • FIG. 4 is a diagram showing a state of a hexagonal valve (rotary type) when the indoor unit performs heating operation;
  • FIG. 4 is a diagram showing a state of a hexagonal valve (rotary type) when the indoor unit performs cooling operation;
  • FIG. 2 is a diagram representatively showing one indoor unit and one hexagonal valve (slide type) corresponding thereto.
  • FIG. 4 is a diagram showing a state of a hexagonal valve (slide type) when the indoor unit performs heating operation;
  • FIG. 4 is a diagram showing a state of a hexagonal valve (slide type) when the indoor unit performs cooling operation
  • FIG. 3 is a refrigerant circuit diagram showing a refrigerant circuit configuration of a refrigeration cycle device 500 of a comparative example
  • FIG. 10 is a diagram showing a state in which a six-way valve (rotary type) indoor unit used in Embodiment 2 performs a heating operation
  • FIG. 10 is a diagram showing a state in which a six-way valve (rotary type) indoor unit used in Embodiment 2 performs a cooling operation
  • FIG. 10 is a diagram showing a state in which a hexagonal valve (slide type) indoor unit used in Embodiment 2 performs a heating operation
  • FIG. 10 is a diagram showing a state in which the hexagonal valve (slide type) indoor unit used in Embodiment 2 performs a cooling operation
  • FIG. 11 is a diagram showing a state in which a hexagonal valve (slide type) indoor unit used in Embodiment 3 performs a heating operation
  • FIG. 10 is a diagram showing a state in the middle of operation switching of a hexagonal valve (slide type) used in Embodiment 3
  • FIG. 10 is a diagram showing a state in which the hexagonal valve (slide type) indoor unit used in Embodiment 3 performs a cooling operation
  • FIG. 10 is a diagram showing a state in the middle of operation switching of a hexagonal valve (rotary type) used in Embodiment 3
  • FIG. 12 is a diagram showing configurations of a relay unit, an indoor unit, and a control device for explaining hexagonal valve control according to Embodiment 4
  • 4 is a flowchart for explaining switching control of a hexagonal valve executed by
  • FIG. 1 is a refrigerant circuit diagram showing a refrigerant circuit configuration of a refrigeration cycle device 300 of Embodiment 1.
  • FIG. 1 The configuration and operation of the refrigeration cycle apparatus 300 shown in FIG. 1 will be described.
  • the refrigeration cycle device 300 is a two-pipe multi-system air conditioner that can simultaneously process cooling operation and heating operation selected in each indoor unit by performing vapor compression refrigeration cycle operation.
  • each component may differ from the actual one. Further, those with a suffix "a” are installed in the indoor unit 303a, and those with a suffix "b" are installed in the indoor unit 303b.
  • the refrigeration cycle device 300 includes a heat source unit 301, a repeater 302, an indoor unit 303a, and an indoor unit 303b.
  • a heat source unit 301 for generating heat.
  • a repeater 302 for generating heat.
  • an indoor unit 303a for generating heat.
  • an indoor unit 303b for storing data.
  • the heat source unit 301 and the repeater 302 are connected by the high pressure connection pipe 6 and the low pressure connection pipe 24 .
  • the outlet side of the check valve 5 and the high pressure pipe H of the repeater 302 are connected by the high pressure connection pipe 6 .
  • the inlet of the check valve 25 and the low pressure pipe L of the repeater 302 are connected by the low pressure connection pipe 24 .
  • the four pipes of the repeater 302 and the indoor unit 303a are connected via a six-way valve 10a.
  • the four pipes of the repeater 302 and the indoor unit 303b are connected via the hexagonal valve 10b.
  • Refrigerants used in the refrigeration cycle device 300 include, for example, HFC (hydrofluorocarbon) refrigerants such as R32 and R410A, and natural refrigerants such as hydrocarbons, carbon dioxide, and ammonia.
  • the operation mode of the heat source unit 301 is determined according to the ratio of the cooling load and the heating load of the indoor unit 303 connected.
  • the refrigeration cycle device 300 executes the following four operation modes.
  • (a) An operation mode of the heat source unit 301 when there is no heating load and all of the indoor units 303 perform cooling operation (hereinafter referred to as cooling only operation mode).
  • heating only operation mode An operation mode of the heat source unit 301 when there is no cooling load and all the indoor units 303 perform heating operation.
  • heating main operation mode An operation mode of the heat source unit 301 when the heating load is large in simultaneous cooling and heating operation in which the indoor unit 303 performs both the cooling operation and the heating operation at the same time.
  • the indoor unit 303 is installed at a location where conditioned air can be blown out to an air-conditioned area.
  • the indoor unit 303 is installed in such a place, for example, by embedding or hanging it in the indoor ceiling, or by hanging it on the wall.
  • the indoor unit 303 is connected to the heat source unit 301 via the repeater 302, the high pressure connection pipe 6 and the low pressure connection pipe 24, and constitutes part of the refrigerant circuit.
  • the indoor unit 303a includes an indoor-side refrigerant circuit that forms part of the refrigerant circuit.
  • the indoor refrigerant circuit is composed of an indoor heat exchanger 12a as a user side heat exchanger and an indoor pressure reducing mechanism 14a connected in series with the indoor heat exchanger 12a.
  • the indoor unit 303a is also provided with an indoor fan (not shown) for supplying conditioned air after heat exchange with the refrigerant in the indoor heat exchanger 12a to an air-conditioned area such as a room.
  • the indoor unit 303b has an indoor-side refrigerant circuit that forms part of the refrigerant circuit.
  • This indoor-side refrigerant circuit is composed of an indoor heat exchanger 12b as a user-side heat exchanger and an indoor pressure reducing mechanism 14b connected in series with the indoor heat exchanger 12b.
  • the indoor unit 303b is also provided with an indoor blower (not shown) for supplying conditioned air after heat exchange with the refrigerant in the indoor heat exchanger 12b to an air-conditioned area such as a room.
  • Each of the indoor heat exchangers 12a and 12b can be configured by, for example, a cross-fin type fin-and-tube heat exchanger configured by heat transfer tubes and a large number of fins. Also, each of the indoor heat exchangers 12a and 12b may be configured by a microchannel heat exchanger, a shell and tube heat exchanger, a heat pipe heat exchanger, or a double tube heat exchanger.
  • the indoor heat exchangers 12a and 12b function as refrigerant evaporators to cool the air in the air-conditioned area. functions as a condenser for the refrigerant and heats the air in the area to be conditioned.
  • An indoor fan (not shown) draws indoor air into each of the indoor units 303a and 303b, heat-exchanges the indoor air with the refrigerant in the indoor heat exchangers 12a and 12b, and then supplies the conditioned air to the air-conditioned area. It has the function to That is, in each of the indoor units 303a and 303b, it is possible to exchange heat between the indoor air taken in by the indoor fan and the refrigerant flowing through the indoor heat exchangers 12a and 12b.
  • the indoor blower can vary the flow rate of conditioned air supplied to the corresponding indoor heat exchanger, and is composed of a fan such as a centrifugal fan or a multi-blade fan and a DC fan motor that drives the fan. and a motor.
  • a fan such as a centrifugal fan or a multi-blade fan
  • a DC fan motor that drives the fan.
  • Heat source unit 301 is installed outdoors, for example, and is connected to indoor unit 303 via high-pressure connection pipe 6, low-pressure connection pipe 24, and relay machine 302. Configure.
  • the heat source unit 301 is provided with two connection pipes 27 and 29 that connect the high-pressure connection pipe 6 and the low-pressure connection pipe 24 in order to keep the flow direction of the refrigerant flowing in and out of the repeater 302 constant.
  • the heat source unit 301 includes an outdoor refrigerant circuit that forms part of the refrigerant circuit.
  • This outdoor refrigerant circuit includes a compressor 1 for compressing refrigerant, a four-way valve 2 for switching the direction of refrigerant flow, an outdoor heat exchanger 3 as a heat source side heat exchanger, and a refrigerant with one direction of flow. It consists of four check valves 5, 25, 26 and 28 which control the flow of refrigerant by only permitting it, and an accumulator 30 for storing excess refrigerant.
  • the heat source unit 301 is also provided with an outdoor fan 4 for supplying air to the outdoor heat exchanger 3 .
  • the compressor 1 sucks refrigerant and compresses the refrigerant to a high temperature and high pressure state.
  • the compressor 1 mounted in the air conditioner according to Embodiment 1 is capable of varying the operating capacity, and is, for example, a positive displacement compressor driven by a motor (not shown) controlled by an inverter. Configured.
  • the case where there is only one compressor 1 is shown as an example, but the present invention is not limited to this, and two or more compressors 1 may be connected in parallel according to the number of connected indoor units. It can be anything.
  • the four-way valve 2 functions as a channel switching device that switches the direction of refrigerant flow depending on the operation mode of the heat source unit 301 .
  • the four-way valve 2 connects the discharge side of the compressor 1 and the outdoor heat exchanger 3 so that the outdoor heat exchanger 3 functions as a condenser for the refrigerant compressed in the compressor 1. It connects the gas side of the heat exchanger 3 and connects the suction side of the compressor 1 and the low-pressure connection pipe 24 side via the check valve 25 .
  • a flow path is formed as indicated by the solid line in the four-way valve 2.
  • the four-way valve 2 passes through the discharge side of the compressor 1 and the check valve 26 so that the outdoor heat exchanger 3 functions as a refrigerant evaporator. Then, the high-pressure connecting pipe 6 side is connected, and the suction side of the compressor 1 and the gas side of the outdoor heat exchanger 3 are connected. In this case, a flow path is formed as indicated by the dashed line in the four-way valve 2 .
  • the check valve 5 is provided between a connection portion a between the high-pressure connection pipe 6 and the connection pipe 27 and a connection portion b between the high-pressure connection pipe 6 and the connection pipe 29, and is directed from the heat source unit 301 to the repeater 302. Refrigerant flow is allowed only in one direction.
  • the check valve 25 is provided between a connecting portion c between the low-pressure connecting pipe 24 and the connecting pipe 27 and a connecting portion d between the low-pressure connecting pipe 24 and the connecting pipe 29, and is directed from the repeater 302 to the heat source unit 301. Refrigerant flow is allowed only in one direction.
  • the check valve 26 is provided in the connection pipe 27 and allows the refrigerant to flow only in the direction from the heat source unit 301 to the repeater 302 .
  • the check valve 28 is provided in the connecting pipe 29 and allows the refrigerant to flow only in the direction from the repeater 302 toward the heat source unit 301 .
  • the refrigerant is permitted to flow only in the direction from the heat source unit 301 to the repeater 302 in the high-pressure connection pipe 6, and in the low-pressure connection pipe 24 Refrigerant is allowed to flow only in the direction from the repeater 302 toward the heat source unit 301 .
  • the flow direction of the refrigerant when the four-way valve 2 is switched is determined.
  • the outdoor heat exchanger 3 can be composed of, for example, a cross-fin fin-and-tube heat exchanger composed of heat transfer tubes and a large number of fins. Also, the outdoor heat exchanger 3 may be composed of a microchannel heat exchanger, a shell and tube heat exchanger, a heat pipe heat exchanger, or a double tube heat exchanger.
  • the outdoor heat exchanger 3 functions as a refrigerant condenser to radiate heat in the cooling only operation mode and the cooling main operation mode, and functions as a refrigerant evaporator to release the refrigerant in the heating only operation mode and the heating main operation mode. Endothermic.
  • the outdoor heat exchanger 3 is connected to the four-way valve 2 on the gas side and to the check valves 5 and 28 on the liquid side.
  • the outdoor blower 4 has a function of sucking outdoor air into the heat source unit 301, exchanging the heat of the outdoor air with the outdoor heat exchanger 3, and then discharging the outdoor air to the outside.
  • the heat source unit 301 exchanges heat between the outdoor air taken in by the outdoor fan 4 and the refrigerant flowing through the outdoor heat exchanger 3 .
  • the outdoor blower 4 can vary the flow rate of air supplied to the outdoor heat exchanger 3, and includes a fan such as a propeller fan and a motor such as a DC fan motor that drives the fan.
  • a fan such as a propeller fan
  • a motor such as a DC fan motor that drives the fan.
  • the accumulator 30 stores liquid refrigerant to prevent liquid backflow to the compressor 1 when an abnormality occurs in the refrigeration cycle device 300 or during a transient response of the operating state accompanying a change in operation control. 1 suction side.
  • the compressor 1, the four-way valve 2, and the outdoor fan 4 are operated as a normal operation controller that performs normal operations including a cooling-only operation mode, a cooling-main operation mode, a heating-only operation mode, and a heating-main operation mode. 100.
  • the control device 100 includes a CPU (Central Processing Unit) 101, a memory 102 (ROM (Read Only Memory) and RAM (Random Access Memory)), an input/output buffer (not shown), and the like.
  • the CPU 101 develops a program stored in the ROM into a RAM or the like and executes it.
  • the program stored in the ROM is a program in which processing procedures of the control device 100 are described.
  • the control device 100 controls each device in the refrigeration cycle device 300 according to these programs. This control is not limited to processing by software, and processing by dedicated hardware (electronic circuit) is also possible.
  • Repeater 302 is installed indoors, for example, is connected to heat source unit 301 via low-pressure connection pipe 24 and high-pressure connection pipe 6, and is connected to indoor unit 303 via pipe 11 and pipe 15. It constitutes a part of the refrigerant circuit.
  • the repeater 302 is interposed between the heat source unit 301 and the indoor unit 303 and has a function of controlling the flow of refrigerant according to the operation required of each indoor unit 303 .
  • the repeater 302 includes a repeater refrigerant circuit that forms part of the refrigerant circuit.
  • This relay refrigerant circuit includes a heat exchange portion 19 and a heat exchange portion 21 for exchanging heat of the refrigerant, expansion valves 20 and 22 for controlling the distribution flow rate of the refrigerant, a low pressure pipe L, and a high pressure pipe H. , a middle pressure junction pipe MJ, a middle pressure branched pipe MB, and six-way valves 10a and 10b.
  • Refrigerant supplied from the high-pressure connecting pipe 6 passes through the expansion valve 20 and the expansion valve 22 and flows into the low-pressure connecting pipe. It is distributed to the pressure branch MB.
  • FIG. 2 is a diagram representatively showing one indoor unit and one corresponding six-way valve (rotary type).
  • FIG. 3 is a diagram showing the state of the hexagonal valve (rotary type) when the indoor unit performs heating operation.
  • FIG. 4 is a diagram showing the state of the hexagonal valve (rotary type) when the indoor unit performs cooling operation.
  • the hexagonal valve 10a connects the pipe 11a to either the low-pressure pipe L or the high-pressure pipe H, and connects the pipe 15a to the medium-pressure junction pipe MJ or the medium-pressure branch pipe. Connect to either one of the MBs.
  • the hexagonal valve 10b connects the pipe 11b to either the low pressure pipe L or the high pressure pipe H, and connects the pipe 15b to the intermediate pressure junction pipe MJ or the intermediate pressure branch pipe. Connect to either one of the MBs.
  • the indoor units 303a and 303b may be collectively referred to as the indoor unit 303, the hexagonal valves 10a and 10b as the hexagonal valve 10, the pipes 11a and 11b as the pipe 11, and the pipes 15a and 15b as the pipe 15. be.
  • the hexagonal valve 10 When the corresponding indoor unit 303 is requested to operate for heating, the hexagonal valve 10 is set as shown in FIG.
  • the hexagonal valve 10 includes a housing 41 and a valve body 42 .
  • a first flow path C1 and a second flow path C2 are formed in the valve body 42 .
  • a heating channel is formed in the hexagonal valve 10 by controlling the rotational position of the valve body 42 as shown in FIG.
  • the ports P2 and P3 communicate with each other through the first flow path C1
  • the ports P5 and P6 communicate with each other through the second flow path C2, and the ports P1 and P4 are closed by the valve body .
  • the six-way valve 10 connects the pipe 11 and the high-pressure pipe H, and connects the pipe 15 and the intermediate-pressure junction pipe MJ.
  • the ends of the low-pressure pipe L and the intermediate-pressure branch pipe MB are blocked at the hexagonal valve 10 .
  • the heating channel is formed in the hexagonal valve 10 as indicated by the solid line in FIG.
  • the hexagonal valve 10 When the corresponding indoor unit 303 is requested to operate for cooling, the hexagonal valve 10 is set as shown in FIG. A cooling flow path is formed in the hexagonal valve 10 by controlling the rotational position of the valve body 42 as shown in FIG.
  • the port P2 communicates with the port P1 through the first flow path C1
  • the port P5 communicates with the port P4 through the second flow path C2
  • the ports P3 and P6 are closed by the valve body .
  • the six-way valve 10 connects the pipe 11 and the low-pressure pipe L, and connects the pipe 15 and the medium-pressure branch MB.
  • the ends of the high-pressure pipe H and the medium-pressure junction pipe MJ are blocked at the hexagonal valve 10 .
  • the cooling channel is formed in the hexagonal valve 10 as indicated by the dashed line in FIG.
  • the heat exchange portion 19 has a flow path 31 and a flow path 32 and is configured to exchange heat between the refrigerant flowing through the flow path 31 and the refrigerant flowing through the flow path 32 .
  • the heat exchange unit 21 has a flow path 33 and a flow path 34 and is configured to exchange heat between the refrigerant flowing through the flow path 33 and the refrigerant flowing through the flow path 34 .
  • a part of the refrigerant flowing through the high-pressure pipe H passes through the flow path 31 and reaches the expansion valve 20 .
  • a medium pressure junction pipe MJ is connected downstream of the expansion valve 20 .
  • the flow path 33 is connected between the intermediate pressure junction pipe MJ and the intermediate pressure period MB.
  • a part of the refrigerant branched from the medium-pressure branch pipe MB flows toward the low-pressure pipe L through the expansion valve 22, the flow path 34, and the flow path 32 in order.
  • Each of the expansion valve 20 and the expansion valve 22 can be configured with a flow rate control device that can variably control the degree of opening.
  • a flow control device for example, a precise flow control device such as an electronic expansion valve or an inexpensive refrigerant flow control device such as a capillary tube can be used in place of the expansion valve.
  • the cooling only operation mode is the operation mode of the refrigeration cycle apparatus when all the indoor units to be operated are in the cooling operation state and there is no indoor unit in the heating operation state.
  • the four-way valve 2 In the cooling only operation mode, the four-way valve 2 is in a state indicated by a solid line, that is, the discharge side of the compressor 1 is connected to the gas side of the outdoor heat exchanger 3, and the suction side of the compressor 1 is connected via the check valve 25. Then, it will be in a state of being connected to the low-pressure connection pipe 24 . All the indoor units 303 are in the cooling operation mode, and both the hexagonal valves 10a and 10b are controlled to form cooling flow paths.
  • the low-pressure gas refrigerant is sucked into the compressor 1 and compressed into a high-temperature, high-pressure gas refrigerant.
  • the high-temperature and high-pressure gas refrigerant is sent to the outdoor heat exchanger 3 via the four-way valve 2, exchanges heat with the outdoor air supplied by the outdoor fan 4, and is condensed to become a high-pressure liquid refrigerant. .
  • This high-pressure liquid refrigerant passes through the high-pressure connection pipe 6 via the check valve 5 and is sent to the high-pressure pipe H of the repeater 302 . After that, the refrigerant flows into the high pressure side flow path 31 of the heat exchange section 19 . The refrigerant flowing into the flow path 31 releases heat to the refrigerant flowing through the flow path 32 on the low pressure side of the heat exchange section 19 . This refrigerant flows out of the flow path 31 and flows into the expansion valve 20 which is fully opened. After passing through the expansion valve 20 , the refrigerant flows into the high pressure side flow path 33 of the heat exchange section 21 and releases heat to the refrigerant flowing through the low pressure side flow path 34 of the heat exchange section 21 . After that, this refrigerant is divided into refrigerant flowing through the expansion valve 22 and refrigerant flowing through the pipes 15a and 15b via the hexagonal valves 10a and 10b.
  • the refrigerant that has flowed into the expansion valve 22 is decompressed, becomes a low-pressure gas-liquid two-phase state, flows into the low-pressure side flow path 34 of the heat exchange section 21, and flows through the high-pressure side flow path 33 of the heat exchange section 21. heated by After that, the refrigerant flows out of the low pressure side flow path 34 of the heat exchange section 21, flows into the low pressure side flow path 32 of the heat exchange section 19, and flows through the high pressure side flow path 31 of the heat exchange section 19. heated by the refrigerant. After that, the refrigerant flows into the low-pressure connection pipe 24 via the bypass connection pipe 23 .
  • the expansion valve 22 is controlled by the control device 100 so that the degree of superheat downstream of the flow path 32 on the low pressure side of the heat exchange section 19 becomes a reference value.
  • the low-pressure gaseous refrigerant evaporated downstream of the low-pressure flow path 32 of the heat exchange section 19 is in a state of having the degree of superheat of the reference value.
  • the expansion valve 22 is controlled so that the refrigerant flows in each of the indoor units 303a and 303b at a flow rate corresponding to the cooling load required in each air-conditioned space.
  • the refrigerant flowing through the pipe 15 from the intermediate pressure branch pipe MB via the hexagonal valve 10 flows into the indoor unit 303 .
  • the pressure is reduced by the indoor decompression mechanism 14 to enter a low-pressure gas-liquid two-phase state and flow into the indoor heat exchanger 12 .
  • the refrigerant exchanges heat with the indoor air supplied by the indoor blower, evaporates, and becomes a low-pressure gas refrigerant.
  • the indoor pressure reducing mechanism 14 controls the flow rate of the refrigerant flowing through the indoor heat exchanger 12, and the indoor heat exchanger 12 has a flow rate corresponding to the cooling load required in the air-conditioned space where the indoor unit 303 is installed. Refrigerant is flowing.
  • the low-pressure gas refrigerant that has cooled the indoor air in the indoor heat exchanger 12 flows out from the indoor heat exchanger 12, flows through the pipe 11, and flows out from the indoor unit 303.
  • This refrigerant flows through the first flow path C1 of the hexagonal valve 10 into the low-pressure connecting pipe 24, passes through the expansion valve 22, and joins with the refrigerant flowing through the bypass connecting pipe 23.
  • the merged refrigerant flows into the heat source unit 301, passes through the check valve 25, the four-way valve 2 and the accumulator 30, and is sucked into the compressor 1 again.
  • the cooling only operation mode all indoor units 303 are in cooling operation, and there is no heating load, only cooling load. Therefore, by controlling the evaporating temperature Te and the operating frequency of the compressor 1, the cooling capacity of the indoor unit 303 during the cooling operation with the maximum temperature difference is controlled. Also, the performance of the outdoor heat exchanger 3 is maximized by maximizing the air volume of the outdoor fan 4. - ⁇ When the number of connected indoor units 303 is large, the cooling capacity is controlled by controlling the degree of opening of the indoor decompression mechanism 14 in the indoor unit 303 with a smaller temperature difference depending on the temperature difference. The degree of opening of the indoor decompression mechanism 14 of the indoor unit 303 during cooling operation with the maximum temperature difference is controlled to be large enough to prevent liquid backflow in the compressor 1 .
  • Cooling-dominant operation mode is when indoor units in cooling operation and indoor units in heating operation coexist, and the cooling air-conditioning load is greater than the heating air-conditioning load. This is the operation mode of the refrigeration cycle device.
  • the cooling main operation mode is an operation mode in which the cooling operation load is larger than the heating operation load at this time.
  • the four-way valve 2 is controlled so that the flow path indicated by the solid line in the four-way valve 2 is formed in the same manner as in the cooling-only operation mode.
  • the hexagonal valves 10a and 10b are controlled so that the hexagonal valve 10a forms a heating path and the hexagonal valve 10b forms a cooling path.
  • the low-pressure gas refrigerant is sucked into the compressor 1 and compressed into a high-temperature and high-pressure gas refrigerant.
  • the high-temperature and high-pressure gas refrigerant is sent to the outdoor heat exchanger 3 via the four-way valve 2, exchanges heat with the outdoor air supplied by the outdoor fan 4, and is condensed into a high-pressure liquid refrigerant.
  • This high-pressure liquid refrigerant passes through the high-pressure connection pipe 6 via the check valve 5, flows into the repeater 302, and is sent to the high-pressure pipe H.
  • the gas refrigerant that has flowed from the high-pressure pipe H through the first flow path C1 of the hexagonal valve 10a into the pipe 11a exchanges heat with the indoor air in the indoor heat exchanger 12a of the indoor unit 303a, and is condensed into a high-pressure liquid. It becomes a refrigerant. Thereafter, the high-pressure liquid refrigerant that has heated the indoor air is decompressed by the indoor decompression mechanism 14a, and becomes intermediate-pressure gas-liquid two-phase or liquid-phase refrigerant.
  • the indoor pressure reducing mechanism 14a controls the flow rate of the refrigerant flowing through the indoor heat exchanger 12a. Refrigerant is flowing. After that, the refrigerant passes through the indoor decompression mechanism 14a, flows out from the indoor unit 303a, and is sent to the intermediate pressure junction pipe MJ via the second flow path C2 of the hexagonal valve 10a.
  • part of the refrigerant that has passed through the high-pressure connection pipe 6 flows into the high-pressure side flow path 31 of the heat exchange section 19, releases heat to the refrigerant flowing through the low-pressure side flow path 32 of the heat exchange section 19, The pressure is reduced by the expansion valve 20 to become intermediate-pressure gas-liquid two-phase or liquid-phase refrigerant.
  • the expansion valve 20 is controlled by the control device 100 so that the differential pressure between the high pressure and the intermediate pressure becomes a predetermined target value.
  • a pressure sensor may be provided in each of the high-pressure pipe H and the medium-pressure junction pipe MJ to detect the pressure difference.
  • the expansion valve 20 controls the flow rate of the refrigerant flowing through the expansion valve 20 so that the differential pressure between the high pressure side and the intermediate pressure side becomes the target value. is controlled to the pressure required to perform In this manner, the expansion valve 20 is controlled such that the refrigerant flows through the indoor unit 303a at a flow rate corresponding to the heating operation load required in the air-conditioned space.
  • the refrigerant that has passed through the expansion valve 20 flows out from the indoor unit 303a, joins the refrigerant that has passed through the second flow path C2 of the hexagonal valve 10a and the medium-pressure junction pipe MJ, and flows into the high pressure side flow path 33 of the heat exchange section 21. flow into
  • the refrigerant flowing through the high pressure side passage 33 of the heat exchange portion 21 releases heat to the refrigerant flowing through the low pressure side passage 34, and then the refrigerant flowing through the expansion valve 22 and the refrigerant flowing through the intermediate pressure branch pipe MB. distributed.
  • the refrigerant that has flowed into the expansion valve 22 is decompressed, becomes a low-pressure gas-liquid two-phase state, and flows into the flow path 34 on the low-pressure side of the heat exchange section 21 .
  • the refrigerant flowing into the flow path 34 is heated by the refrigerant flowing through the flow path 33 on the high pressure side of the heat exchange section 21 .
  • the refrigerant flows into the low pressure side flow path 32 of the heat exchange section 19 is heated by the refrigerant flowing through the high pressure side flow path 31 in the heat exchange section 19, and passes through the bypass connection pipe 23 to the low pressure connection pipe. Flow into 24.
  • the expansion valve 22 is controlled by the control device 100 so that the degree of superheat on the downstream side of the low-pressure side of the heat exchange section 19 becomes a target value.
  • the refrigerant that has flowed into the second flow path C2 of the hexagonal valve 10b flows into the indoor unit 303b via the pipe 15b.
  • the refrigerant that has flowed into the indoor unit 303b is decompressed by the indoor decompression mechanism 14b, becomes a low-pressure gas-liquid two-phase state, and flows into the indoor heat exchanger 12b.
  • the refrigerant passing through the indoor heat exchanger 12b exchanges heat with the indoor air and evaporates to become a low-pressure gas refrigerant.
  • the indoor decompression mechanism 14b controls the flow rate of the refrigerant flowing through the indoor heat exchanger 12b. Refrigerant is flowing. The refrigerant that has cooled the indoor air in the indoor heat exchanger 12b flows out from the indoor unit 303b.
  • the refrigerant flowing out of the indoor unit 303b flows through the pipe 11b and flows into the low-pressure pipe L via the first flow path C1 of the hexagonal valve 10b.
  • the refrigerant that has flowed into the low-pressure pipe L joins the refrigerant that has flowed into the expansion valve 22 and passed through the bypass connection pipe 23 , and is sent to the low-pressure connection pipe 24 .
  • the merged refrigerant then flows into the heat source unit 301, passes through the check valve 25, the four-way valve 2 and the accumulator 30, and is sucked into the compressor 1 again.
  • the cooling load and heating load of the indoor unit 303 exist at the same time, and the cooling load is greater than the heating load. Therefore, the evaporation temperature Te is controlled by the operating frequency of the compressor 1 to control the cooling capacity of the indoor unit 303 during the cooling operation with the maximum temperature difference. Also, the condensing temperature Tc is controlled by the air volume of the outdoor fan 4 to control the heating capacity of the indoor unit 303 during the heating operation with the maximum temperature difference.
  • the air conditioning capacity is controlled by controlling the degree of opening of the indoor decompression mechanism 14 according to the temperature difference in the indoor units 303 where the temperature difference is not the largest.
  • the degree of opening of the indoor decompression mechanism 14 of the indoor unit 303 during cooling operation with the maximum temperature difference is controlled to be large enough to prevent liquid backflow in the compressor 1 .
  • the degree of opening of the indoor decompression mechanism 14 of the indoor unit 303 during heating operation with the maximum temperature difference is controlled to be large so that the performance of the indoor heat exchanger 12 is maximized.
  • the outdoor blower 4 controls the heating capacity of the indoor unit 303a.
  • the indoor decompression mechanism 14 controls the cooling capacity and heating capacity of the indoor units whose temperature difference is not the maximum.
  • the heating only operation mode is the operation mode of the refrigeration cycle apparatus when all the indoor units to be operated are in the heating operation state and no indoor units are in the cooling operation state.
  • the four-way valve 2 is in a state indicated by a dashed line, that is, the discharge side of the compressor 1 is connected to the high pressure connection pipe 6 via the check valve 26, and the suction side of the compressor 1 is connected to the outdoor heat exchange. It is in a state of being connected to the gas side of the vessel 3. All the indoor units 303 are in the heating operation mode, and both the hexagonal valves 10a and 10b are controlled to form heating flow paths.
  • the compressor 1, the outdoor fan 4, and the indoor fan (not shown) are started in this state of the refrigerant circuit, the low-pressure gas refrigerant is sucked into the compressor 1 and compressed into a high-temperature and high-pressure gas refrigerant. . After that, the high-temperature and high-pressure gas refrigerant flows into the repeater 302 via the four-way valve 2 and the check valve 26 . The refrigerant that has flowed into the repeater 302 flows into the indoor unit 303 via the high-pressure pipe H and the first flow path C1 of the hexagonal valve 10 .
  • the refrigerant that has flowed into the indoor unit 303 flows into the indoor heat exchanger 12 , exchanges heat with indoor air, condenses into a high-pressure liquid refrigerant, and flows out of the indoor heat exchanger 12 .
  • the refrigerant that heats the indoor air in the indoor heat exchanger 12 is decompressed by the indoor decompression mechanism 14 and becomes intermediate-pressure gas-liquid two-phase or liquid-phase refrigerant.
  • the refrigerant that has passed through the indoor decompression mechanism 14 flows out of the indoor unit 303 and flows into the heat exchange section 21 via the second flow path C2 of the hexagonal valve 10 and the intermediate pressure junction pipe MJ. Note that the expansion valve 20 is controlled to be fully closed.
  • the refrigerant flowing into the high pressure side passage 33 of the heat exchanging portion 21 releases heat to the refrigerant flowing through the low pressure side passage 34 of the heat exchanging portion 21, and then flows into the expansion valve 22 to be decompressed. It becomes a low-pressure gas-liquid two-phase refrigerant.
  • the expansion valve 22 is controlled by the control device 100 so that the differential pressure between the high pressure and the intermediate pressure becomes the target value.
  • the differential pressure between high and intermediate pressures can be detected by a pressure sensor (not shown). In this manner, the expansion valve 22 is controlled such that the refrigerant flows through the indoor unit 303 at a flow rate corresponding to the heating operation load required in the air-conditioned space.
  • the refrigerant that has passed through the expansion valve 22 is then heated in the low pressure side flow path 34 of the heat exchange section 21 by the refrigerant flowing through the high pressure side flow path 33 of the heat exchange section 21, and further flows through the low pressure side of the heat exchange section 19. , and flows into the low-pressure connection pipe 24 via the bypass connection pipe 23 .
  • the condensing temperature Tc is controlled by the operating frequency of the compressor 1 to control the heating capacity of the indoor unit 303 during the heating operation with the maximum temperature difference.
  • the performance of the outdoor heat exchanger 3 is maximized by maximizing the air volume of the outdoor fan 4. - ⁇ When the number of connected indoor units 303 is large, the heating capacity is controlled by controlling the opening degree of the indoor decompression mechanism 14 according to the temperature difference in the indoor units 303 where the temperature difference is not the largest. In addition, the degree of opening of the indoor decompression mechanism 14 of the indoor unit 303 during heating operation with the maximum temperature difference is controlled to be large so that the performance of the indoor heat exchanger 12 is maximized.
  • Heating main operation mode is when indoor units in cooling operation and indoor units in heating operation are mixed, and the heating and air conditioning load is greater than the cooling and air conditioning load. This is the operation mode of the refrigeration cycle device.
  • the indoor unit 303b is in the cooling operation state
  • the indoor unit 303a is in the heating operation state.
  • the heating main operation mode is an operation mode in which the heating operation load is greater than the cooling operation load at this time.
  • the four-way valve 2 is controlled in the same way as in the heating only operation mode.
  • the hexagonal valves 10a and 10b are controlled so that the hexagonal valve 10a forms a heating path and the hexagonal valve 10b forms a cooling path.
  • This high-pressure liquid refrigerant passes through the high-pressure connecting pipe 6 via the four-way valve 2 and the check valve 26, flows into the repeater 302, and is sent to the high-pressure pipe H.
  • the gas refrigerant that has flowed from the high-pressure pipe H through the first flow path C1 of the hexagonal valve 10a into the pipe 11a exchanges heat with the indoor air in the indoor heat exchanger 12a of the indoor unit 303a, and is condensed into a high-pressure liquid. It becomes a refrigerant. Thereafter, the high-pressure liquid refrigerant that has heated the indoor air is decompressed by the indoor decompression mechanism 14a, and becomes intermediate-pressure gas-liquid two-phase or liquid-phase refrigerant.
  • the refrigerant that has passed through the indoor decompression mechanism 14a flows out from the indoor unit 303a, passes through the pipe 15a, the second flow path C2 of the hexagonal valve 10a, and the medium pressure junction pipe MJ, and reaches the high pressure side of the heat exchange unit 21. It flows into the channel 33 . Note that the expansion valve 20 is controlled to be fully closed.
  • the refrigerant flowing into the high pressure side flow path 33 of the heat exchange section 21 releases heat to the refrigerant flowing through the low pressure side flow path 34 of the heat exchange section 21 .
  • Refrigerant that has passed through the flow path 33 is divided into refrigerant heading to the expansion valve 22 and refrigerant heading to the intermediate-pressure branch pipe MB.
  • the refrigerant that has flowed into the expansion valve 22 after distribution is decompressed into a low-pressure gas-liquid two-phase state, and flows into the flow path 34 on the low-pressure side of the heat exchange section 21 .
  • the expansion valve 22 is controlled by the controller 100 so that the differential pressure between the high pressure and the intermediate pressure becomes a target value.
  • the refrigerant that has flowed into the flow path 34 of the heat exchange section 21 is heated by the refrigerant flowing through the high pressure side flow path 33 of the heat exchange section 21, then flows into the low pressure side flow path 32 of the heat exchange section 19, and is bypassed. It flows into the low-pressure connecting line 24 via the connecting line 23 .
  • the refrigerant that has flowed into the intermediate pressure portion period MB after distribution flows into the indoor unit 303b via the second flow path C2 of the hexagonal valve 10b and the pipe 15b.
  • the refrigerant that has flowed into the indoor unit 303b is first decompressed by the indoor decompression mechanism 14b, becomes a low-pressure gas-liquid two-phase state, and flows into the indoor heat exchanger 12b.
  • the refrigerant that has flowed into the indoor heat exchanger 12b exchanges heat with the indoor air and evaporates to become a low-pressure gas refrigerant.
  • the low-pressure gas refrigerant that has cooled the indoor air in the indoor heat exchanger 12b flows out from the indoor heat exchanger 12b, flows through the pipe 11b, and flows out from the indoor unit 303b.
  • the refrigerant flowing out of the indoor unit 303b passes through the first flow path C1 of the hexagonal valve 10b and the low-pressure pipe L, joins the refrigerant flowing through the bypass connection pipe 23, and then flows into the low-pressure connection pipe 24.
  • the merged refrigerant flows into the heat source unit 301, passes through the check valve 28, and flows into the outdoor heat exchanger 3.
  • the refrigerant that has flowed into the outdoor heat exchanger 3 exchanges heat with the outdoor air supplied by the outdoor blower 4 and evaporates to become a low-pressure gas refrigerant.
  • the refrigerant is sucked into the compressor 1 again after passing through the accumulator 30 via the flow path on the dashed line side of the four-way valve 2 .
  • the heating load and cooling load of the indoor unit 303 exist at the same time, and the heating load is greater than the cooling load. Therefore, the condensing temperature Tc is controlled by the operating frequency of the compressor 1 to control the heating capacity of the indoor unit 303 during the heating operation with the maximum temperature difference. Also, the evaporation temperature Te is controlled by the air volume of the outdoor fan 4 to control the cooling capacity of the indoor unit 303 during the cooling operation with the maximum temperature difference.
  • the air conditioning capacity is controlled by controlling the degree of opening of the indoor decompression mechanism 14 according to the temperature difference in the indoor units 303 where the temperature difference is not the largest.
  • the degree of opening of the indoor decompression mechanism 14 of the indoor unit 303 during cooling operation with the maximum temperature difference is controlled to be large enough to prevent liquid backflow in the compressor 1 .
  • the degree of opening of the indoor decompression mechanism 14 of the indoor unit 303 during heating operation with the maximum temperature difference is controlled to be large so that the performance of the indoor heat exchanger 12 is maximized.
  • the heating capacity of the indoor unit 303a is controlled by the compressor 1.
  • the outdoor fan 4 controls the cooling capacity of the indoor unit 303b.
  • the indoor decompression mechanism 14 controls the cooling capacity and heating capacity of the indoor unit whose temperature difference is not the maximum.
  • the indoor unit is operated by the flow path switching function of the hexagonal valve in any of the cooling-only operation mode, cooling-main operation, heating-only operation, and heating-main operation. cooling operation and heating operation can be switched individually.
  • FIGS. 1 to 4 Modification of hexagonal valve
  • the structure of the valve body of the hexagonal valve is a rotary type valve body, but a slide type valve body may be adopted.
  • FIG. 5 is a diagram representatively showing one indoor unit and one corresponding hexagonal valve (slide type).
  • FIG. 6 is a diagram showing the state of the hexagonal valve (slide type) when the indoor unit performs heating operation.
  • FIG. 7 is a diagram showing the state of the hexagonal valve (slide type) when the indoor unit performs cooling operation.
  • a slide type hexagonal valve 410 is used instead of the rotary hexagonal valve 10 in the configuration shown in FIG.
  • the hexagonal valve 410a connects the pipe 11a to either the low-pressure pipe L or the high-pressure pipe H, and connects the pipe 15a to the medium-pressure junction pipe MJ or the medium-pressure branch pipe. Connect to either one of the MBs.
  • the hexagonal valve 410b connects the pipe 11b to either the low pressure pipe L or the high pressure pipe H, and connects the pipe 15b to the medium pressure junction pipe MJ or the medium pressure branch pipe. Connect to either one of the MBs.
  • the indoor units 303a and 303b may be collectively referred to as the indoor unit 303, the hexagonal valves 10a and 10b as the hexagonal valve 10, the pipes 11a and 11b as the pipe 11, and the pipes 15a and 15b as the pipe 15. be.
  • Hexagonal valve 410 When the corresponding indoor unit 303 is requested to operate for heating, the hexagonal valve 410 is set as shown in FIG. Hexagonal valve 410 includes housing 411 and valve body 412 . A first flow path C1 and a second flow path C2 are formed in the valve body 412 . A heating channel is formed in the hexagonal valve 410 by controlling the sliding position of the valve body 412 as shown in FIG. In this case, the port P2 and the port P3 communicate with each other through the first flow path C1, the port P5 and the port P6 communicate with each other through the second flow path C2, and the ports P1 and P4 are closed by the valve element 412.
  • the six-way valve 410 connects the pipe 11 and the high-pressure pipe H, and connects the pipe 15 and the intermediate-pressure junction pipe MJ.
  • the ends of the low-pressure pipe L and the intermediate-pressure branch pipe MB are blocked at the hexagonal valve 410 .
  • the heating channel is formed in the hexagonal valve 410, the channel is formed in the hexagonal valve 410 as shown in FIG.
  • the hexagonal valve 410 When the corresponding indoor unit 303 is requested to operate for cooling, the hexagonal valve 410 is set as shown in FIG. A cooling flow path is formed in the hexagonal valve 410 by controlling the sliding position of the valve body 412 as shown in FIG.
  • the port P2 communicates with the port P1 through the first channel C1
  • the port P5 communicates with the port P4 through the second channel C2
  • the ports P3 and P6 are closed by the valve element 412.
  • the six-way valve 410 connects the pipe 11 and the low-pressure pipe L, and connects the pipe 15 and the medium-pressure branch MB.
  • the ends of the high-pressure pipe H and the intermediate-pressure junction pipe MJ are blocked at the hexagonal valve 410 .
  • FIG. 8 is a refrigerant circuit diagram showing a refrigerant circuit configuration of a refrigeration cycle device 500 of a comparative example.
  • a refrigerating cycle device 500 has a repeater 502 instead of the repeater 302 in the configuration of the refrigerating cycle device 300 in FIG.
  • the refrigeration cycle apparatus of the comparative example shown in FIG. 8 is a four-way valve that operates the outdoor heat exchanger 3 in the heat source unit 301 as a condenser by means of a refrigerant flow switching mechanism using one four-way valve and four check valves.
  • the low-pressure connecting pipe 24 is used as a low-pressure pipe
  • the high-pressure connecting pipe 6 is used as a high-pressure pipe. It has the advantage of simplifying construction compared to a system that connects the outdoor unit and the repeater with three pipes, which is common as a simultaneous cooling and heating air conditioning system.
  • the first switching state of the four-way valve 2 corresponds to the cooling only operation mode and the cooling main operation described above
  • the second switching state of the four way valve corresponds to the heating only operation and the heating main operation described above.
  • each of the indoor units 303 is connected to the repeater 502 by two refrigerant pipes each of pipes 11 and 15 .
  • the pipe 11 is connected to the high-pressure pipe H via the solenoid valve 511 and to the low-pressure pipe L via the solenoid valve 512 .
  • the pipe 15 is also connected to the intermediate pressure junction pipe MJ through a check valve 514 and to the intermediate pressure branch pipe MB through a check valve 515 .
  • an electromagnetic valve 513 and an orifice 501 are provided in parallel to the electromagnetic valve 512 that connects the pipe 11 and the low-pressure pipe L.
  • the switching between cooling operation and heating operation of each indoor unit is performed by switching the open/close state of the solenoid valve and check valve in the repeater corresponding to the connection port of each indoor unit.
  • the solenoid valve 511 is closed and the solenoid valve 512 is opened, whereby the indoor unit 303 is connected to the low pressure pipe L.
  • the check valve 514 is closed and the check valve 515 is closed.
  • the indoor unit 303 is connected to the intermediate pressure branch pipe MB.
  • the solenoid valve 511 is opened and the solenoid valve 512 is closed, so that the indoor unit 303 is connected to the high-pressure pipe H.
  • the check valve 514 is circulated and the check valve 515 is closed.
  • the indoor unit 303 is connected to the medium pressure junction pipe MJ.
  • the solenoid valve 511 when switching the operation of the indoor unit 303 from heating to cooling, the solenoid valve 511 is switched from the open state to the closed state, and the solenoid valve 512 is switched from the closed state to the open state.
  • the solenoid valve 512 is opened with a pressure difference between both ends, the high-temperature and high-pressure refrigerant in the indoor unit 303 during heating operation rapidly flows out while expanding toward the low-pressure pipe L, generating a loud refrigerant expansion noise. .
  • a solenoid valve 513 having a diameter smaller than that of the solenoid valve 512 is provided in parallel with the solenoid valve 512, and the solenoid valve 513 is opened before the solenoid valve 512 is opened, thereby After the pressure inside the low-pressure pipe is gradually equalized, the electromagnetic valve 512 is opened to suppress the refrigerant expansion noise.
  • a vacuum pump is connected to the service port in the heat source unit 301 to remove air or refrigerant from the refrigerating cycle device. may be collected.
  • the electromagnetic valve is generally in a closed state in a non-energized state, and if the opening degree of the indoor pressure reducing mechanism 14 is unknown, the indoor pressure reducing mechanism 14 may also be fully closed. Even if the vacuum pump is operated, there is a possibility that the air or refrigerant clogged in the indoor heat exchanger 12 cannot be recovered.
  • the refrigerant is additionally charged into the refrigeration cycle device while the air or refrigerant in the refrigeration cycle device is incompletely collected, there is a risk that the composition or weight of the refrigerant will differ from the design value, resulting in the inability to demonstrate the required performance. Furthermore, there is a risk of malfunction of the device due to contamination of the refrigerant with impurities such as water or air.
  • an orifice 501 is generally provided in parallel with the solenoid valve 512 to always ensure communication between the interior of the indoor unit 303 and the heat source unit 301 via the low pressure pipe L and the low pressure connection pipe 24 .
  • connection ports such as the maximum number of indoor units that can be connected to 8 or 16 units
  • the hexagonal valve may be of the rotary type shown in FIGS. 2 to 4 or the slide type shown in FIGS.
  • the refrigerant flow path is gradually opened and closed along with the movement of the valve body, and it takes several seconds to equalize the pressure. Therefore, refrigerant expansion noise can be reduced without parallel installation of a small-diameter solenoid valve.
  • the indoor unit 303 communicates with the heat source unit 301 via the high-pressure pipe H or the low-pressure pipe L in both the first switching state and the second switching state. No loss of performance.
  • check valves have the risk of valve body vibration noise due to the balance of gravity, fluid force, and buoyancy, or the check valve breakage due to scraping of the inner wall of the check valve.
  • the valve body resin may be scraped or swelled to cause deformation, which may cause the check valve to fail to close, resulting in system malfunction.
  • Embodiment 1 by using a hexagonal valve to replace the function of the check valve, problems caused by the check valve can be resolved.
  • FIG. 9 is a diagram showing a state in which a hexagonal valve (rotary type) indoor unit used in Embodiment 2 performs heating operation.
  • FIG. 10 is a diagram showing a state in which the six-way valve (rotary type) indoor unit used in Embodiment 2 performs cooling operation.
  • Hexagonal valve 450 includes housing 451 and valve body 452 .
  • FIG. 11 is a diagram showing a state in which the hexagonal valve (slide type) indoor unit used in Embodiment 2 performs heating operation.
  • FIG. 12 is a diagram showing a state in which the hexagonal valve (slide type) indoor unit used in Embodiment 2 performs cooling operation.
  • Hexagonal valve 460 includes housing 461 and valve body 462 .
  • the first flow path C1 communicating with the pipe 11 is maintained during both the cooling operation and the heating operation of the indoor unit 303.
  • Vapor refrigerant flows.
  • liquid refrigerant flows through the second flow path C2 that communicates with the pipe 15 during the cooling operation of the indoor unit 303, and gas-liquid refrigerant flows during the heating operation of the indoor unit 303.
  • a phase refrigerant flows.
  • vapor refrigerants Compared to liquid refrigerants or gas-liquid two-phase refrigerants, vapor refrigerants have a lower density and a higher flow velocity. can be reduced.
  • the flow channel cross-sectional area of the first flow channel C1 is replaced by the flow channel cross-sectional area of the second flow channel C2.
  • the minimum dimension among the inner diameters of the high-pressure pipe H, the low-pressure pipe L, and the pipe 11 is is larger than the maximum inner diameter of each of the intermediate pressure junction pipe MJ, the intermediate pressure branch pipe MB, and the pipe 15, the pipes connected to the hexagonal valve can be made compact and the cost can be reduced.
  • FIG. 13 is a diagram showing a state in which a hexagonal valve (slide type) indoor unit used in Embodiment 3 performs a heating operation.
  • FIG. 14 is a diagram showing a state in the middle of operation switching of the hexagonal valve (slide type) used in the third embodiment.
  • FIG. 15 is a diagram showing a state in which the hexagonal valve (slide type) indoor unit used in Embodiment 3 performs cooling operation.
  • Hexagonal valve 470 includes housing 471 and valve body 472 .
  • the first flow path C1 in the hexagonal valve 470 is switched between a first switching state in which the heating flow path of the hexagonal valve 470 is formed and a second switching state in which the cooling flow path is formed.
  • a first flow path C1 is formed so as to communicate with at least one of the high-pressure pipe H and the low-pressure pipe L at an arbitrary position of the valve body 472 between them.
  • FIGS. 13 to 15 show an example of a slide-type hexagonal valve
  • the same effect can be obtained even with a rotary-type hexagonal valve by forming a similar first flow path C1 in the valve body.
  • FIG. 16 is a diagram showing a state in the middle of operation switching of the hexagonal valve (rotary type) used in the third embodiment. As shown in FIG. 16, even in a rotary hexagonal valve, if a similar first flow path C1 is formed in the valve body, the inside of the indoor heat exchanger 12 will communicate with at least one of the high-pressure pipe H and the low-pressure pipe L. .
  • Embodiment 4 When the pipe 11 communicates with both the high-pressure pipe H and the low-pressure pipe L at a valve body position between the first switching state and the second switching state of the hexagonal valve, switching a plurality of hexagonal valves at the same time causes a high pressure Since the pipe H and the low-pressure pipe L are short-circuited via the first flow path C1 in the hexagonal valve, in the case of a differential pressure operated valve, the operating differential pressure required for valve switching cannot be maintained, and the valve body is in the middle of switching. There is a risk that it will not be possible to recover while it is stopped at the position.
  • Embodiment 4 is characterized in that when a plurality of hexagonal valves are switched according to the cooling/heating operation state of the indoor unit, the hexagonal valves are switched one by one. By switching the hexagonal valves one by one instead of switching the plurality of hexagonal valves at the same time, the above problems can be prevented.
  • switching of the next hexagonal valve is started.
  • an expected switching required time for example, 5 seconds
  • FIG. 17 is a diagram showing configurations of a repeater, an indoor unit, and a control device for explaining the hexagonal valve control of Embodiment 4.
  • FIG. 17 is a diagram showing configurations of a repeater, an indoor unit, and a control device for explaining the hexagonal valve control of Embodiment 4.
  • the indoor unit 303a further includes a control device 110a.
  • the indoor unit 303b further includes a control device 110b.
  • Repeater 302 further includes sensor 120a and sensor 120b.
  • the hexagonal valves 10a and 10b are controlled by the control device 100.
  • the control device 100 controls the hexagonal valves 10a and 10b based on signals from the control device 110a, the sensor 120a, the control device 110b and the sensor 120b.
  • FIG. 18 is a flowchart for explaining the hexagonal valve switching control executed by the control device 100.
  • the control device 100 stores a switching enable/disable flag indicating whether or not the hexagonal valve can be switched, and constitutes a switching standby counter that counts the number of hexagonal valves waiting to be switched.
  • step S1 the control device 100 initializes the switching enable/disable flag to "permit” and also initializes the switching standby counter to zero.
  • control device 100 determines whether a switching request signal requesting switching of the corresponding hexagonal valve has been received from either the control device 110a of the indoor unit 303a or the control device 110b of the indoor unit 303b. If the switching request signal has been received (YES in S2), control device 100 adds 1 to the switching standby counter in step S3, and advances the process to step S4. On the other hand, if the switching request signal has not been received (NO in S2), the process proceeds to step S4 without executing the process of step S3.
  • step S4 the control device 100 determines whether the count value of the switching standby counter is "1 or more” and the switching permission flag is "permitted”.
  • step S5 the control device 100 sends a switching signal to the next hexagonal valve in standby. The command is transmitted, the switching of the hexagonal valve is started, the switching permission/prohibition flag is changed to "not permitted", and the process proceeds to step S6.
  • step S6 without executing step S5.
  • the control device 100 subsequently determines whether or not the state of the hexagonal valve during switching has stabilized through the processing of steps S6 and S7.
  • step S6 it is determined whether or not the temperature or pressure measurement value measured by the sensor 120 corresponding to the hexagonal valve that is being switched falls within a specified range corresponding to the completion of switching.
  • step S7 it is determined whether or not a specified time has passed since the switching signal was transmitted to the hexagonal valve.
  • step S8 the control device 100 changes the switching permission flag from "not permitted” to "permitted", and the switching is performed. Decrease the value of the wait counter by one.
  • step S5 the processing of step S5 and the processing of step S8, the execution order of steps S6 and S7 may be exchanged, or only one of steps S6 and S7 may be performed.
  • step S9 the control device 100 determines whether or not the count value of the switching standby counter is zero. If the count value is not zero (NO in S9), there are still hexagonal valves to be switched, so the processes after step S2 are repeated. If the count value is zero (YES in S9), there are no hexagonal valves to be switched, so the processing of this flowchart ends.
  • a refrigeration cycle apparatus 300 shown in FIG. 1 includes a heat source unit 301 having a compressor 1 and an outdoor heat exchanger 3, a plurality of indoor units 303a and 303b, and between the heat source unit 301 and the plurality of indoor units 303a and 303b. and a repeater 302 that is connected and relays the refrigerant.
  • the repeater 302 includes a first pipe (high-pressure pipe H) through which the refrigerant sent from the heat source unit 301 passes, a second pipe (low-pressure pipe L) through which the refrigerant returning to the heat source unit passes, and a third pipe (medium-pressure pipe).
  • each of the plurality of hexagonal valves 10a and 10b includes a first port P1 connected to the second pipe and a first port P1 connected to one end of the refrigerant channel of the corresponding indoor unit.
  • the valve element 42 is configured to switch the communication state of each of the plurality of hexagonal valves 10a and 10b between the first switching state shown in FIG. 3 and the second switching state shown in FIG.
  • the first flow path C1 communicates the first port P1 and the second port P2, and the second flow path C2 communicates the fourth port P4 and the fifth port P5. At this time, the third port P3 and the sixth port P6 are closed.
  • the first flow path C1 communicates the second port P2 and the third port P3, and the second flow path C2 communicates the fifth port P5 and the sixth port P6. At this time, the first port P1 and the fourth port P4 are closed.
  • the cross-sectional area of the first channel C1 is greater than or equal to the cross-sectional area of the second channel C2.
  • three pipes (low pressure pipe L, pipe 11a (or 11b), the minimum dimension of the inner diameter of the high-pressure pipe H) is three pipes (medium-pressure branch pipe MB , the pipe 15a (or 15b) and the medium pressure junction pipe MJ).
  • the valve body 472 slides in the housing 471 to switch the communication state of each of the hexagonal valves 470a and 470b between the first switching state and the second switching state. configured as possible.
  • the valve body 452 is configured to be able to switch the communication state of each of the hexagonal valves 450a and 450b between the first switching state and the second switching state by rotating inside the housing 451.
  • the first flow path C1 is arranged such that the second port P2 is connected to the first port P1 or It is formed to communicate with at least one of the third ports P3.
  • the refrigeration cycle device further includes a control device 100 that controls switching of the plurality of hexagonal valves.
  • the control device 100 switches the first hexagonal valve 10a as shown in S5 of FIG. is started, and after switching of the first hexagonal valve 10a is completed, switching of the second hexagonal valve 10b is started.
  • the refrigeration cycle device further includes a sensor 120a that detects the switching state of the first hexagonal valve 10a.
  • the control device 100 determines completion of switching of the first hexagonal valve 10a based on the output of the sensor 120a.
  • the sensor 120a may be a pressure sensor or a temperature sensor.
  • the control device 100 starts switching the first hexagonal valve and As shown in S7 of 18, it is configured to start switching the second hexagonal valve 10b after a predetermined specified time or more has elapsed.

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  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Mechanical Engineering (AREA)
  • Thermal Sciences (AREA)
  • General Engineering & Computer Science (AREA)
  • Compression-Type Refrigeration Machines With Reversible Cycles (AREA)

Abstract

Ce dispositif à cycle de réfrigération comprend une unité de source de chaleur (301), une pluralité d'unités intérieures (303a, 303b) et une unité de relais (302) pour les relais. L'unité de relais (302) comporte une pluralité de soupapes à six voies (10a, 10b) qui sont disposées de manière à correspondre à la pluralité d'unités intérieures (303a, 303b), respectivement. Chacune des soupapes à six voies présente un boîtier (41) présentant des premier à sixième orifices, et un corps de soupape (42) qui est disposé à l'intérieur du boîtier et formé avec un premier trajet d'écoulement et un second trajet d'écoulement. Dans le second état de commutation, le premier trajet d'écoulement permet une communication entre le premier orifice et le deuxième orifice, et le second trajet d'écoulement permet une communication entre le quatrième orifice et le cinquième orifice. Dans le premier état de commutation, le premier trajet d'écoulement permet une communication entre le deuxième orifice et le troisième orifice, et le second trajet d'écoulement permet une communication entre le cinquième orifice et le sixième orifice.
PCT/JP2021/028744 2021-08-03 2021-08-03 Dispositif à cycle de réfrigération WO2023012891A1 (fr)

Priority Applications (4)

Application Number Priority Date Filing Date Title
CN202180100966.0A CN117716187A (zh) 2021-08-03 2021-08-03 制冷循环装置
EP21952721.5A EP4382834A1 (fr) 2021-08-03 2021-08-03 Dispositif à cycle de réfrigération
JP2023539414A JPWO2023012891A1 (fr) 2021-08-03 2021-08-03
PCT/JP2021/028744 WO2023012891A1 (fr) 2021-08-03 2021-08-03 Dispositif à cycle de réfrigération

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Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2011112233A (ja) 2009-11-24 2011-06-09 Mitsubishi Electric Corp 空気調和装置
WO2017145219A1 (fr) * 2016-02-22 2017-08-31 三菱電機株式会社 Appareil à cycle frigorifique
WO2019215916A1 (fr) * 2018-05-11 2019-11-14 三菱電機株式会社 Système à cycle de réfrigération
JP2020148254A (ja) * 2019-03-13 2020-09-17 株式会社不二工機 流路切換弁
WO2021106084A1 (fr) * 2019-11-26 2021-06-03 三菱電機株式会社 Dispositif à cycle de réfrigération

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2011112233A (ja) 2009-11-24 2011-06-09 Mitsubishi Electric Corp 空気調和装置
WO2017145219A1 (fr) * 2016-02-22 2017-08-31 三菱電機株式会社 Appareil à cycle frigorifique
WO2019215916A1 (fr) * 2018-05-11 2019-11-14 三菱電機株式会社 Système à cycle de réfrigération
JP2020148254A (ja) * 2019-03-13 2020-09-17 株式会社不二工機 流路切換弁
WO2021106084A1 (fr) * 2019-11-26 2021-06-03 三菱電機株式会社 Dispositif à cycle de réfrigération

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JPWO2023012891A1 (fr) 2023-02-09
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