CN118176395A - Air conditioner - Google Patents

Abstract

An air conditioner (100) is provided with a Refrigerant Circuit (RC) and a blower (32). The refrigerant flow path switching mechanism (RF) is configured to be switched in a first switching state such that the refrigerant flows in the Refrigerant Circuit (RC) in the order of the reheater (21), the second expansion valve (23), and the cooler (22). The refrigerant flow path switching mechanism (RF) is configured to be switched in a second switching state such that the refrigerant flows in the Refrigerant Circuit (RC) in the order of the reheater (21), the second expansion valve (23), and the cooler (22). The reheater (21) and the cooler (22) are configured such that air blown by the blower (32) passes through the reheater (21) after passing through the cooler (22) in both the first switching state and the second switching state.

Description

Air conditioner

Technical Field

The present disclosure relates to air conditioners.

Background

An air conditioner is known, which has: an outdoor unit provided with an outdoor heat exchanger functioning as a condenser; an indoor unit having a first indoor heat exchanger functioning as a cooler and a second indoor heat exchanger functioning as a reheater; and a compressor circulating the refrigerant among the outdoor heat exchanger, the first indoor heat exchanger, and the second indoor heat exchanger. In this air conditioner, the temperature and humidity of air blown out from the indoor unit to the space to be air-conditioned are respectively adjusted by heating the air cooled and dehumidified by the first indoor heat exchanger by the second indoor heat exchanger. Such an air conditioner is described in, for example, japanese patent application laid-open No. 2002-89998 (patent document 1).

Prior art literature

Patent literature

Patent document 1: japanese patent laid-open No. 2002-89998

Disclosure of Invention

Problems to be solved by the invention

However, in the air conditioner described in the above publication, only one four-way valve is used as the refrigerant flow path switching mechanism. Therefore, when the cooling main operation and the heating main operation are performed in correspondence with the two switching states of the four-way valve, the direction of the refrigerant flowing through the indoor unit is reversed during the cooling main operation and the heating main operation. Therefore, the indoor heat exchanger functioning as a cooler and the indoor heat exchanger functioning as a reheater are replaced in the cooling main operation and the heating main operation. As a result, in either one of the cooling main operation and the heating main operation, the air heated by the reheater is cooled by the cooler, and therefore sufficient dehumidification cannot be performed.

The present disclosure has been made in view of the above-described problems, and an object thereof is to provide an air conditioner capable of making the directions of the refrigerant flowing through the reheater and the cooler the same in both the cooling main operation and the heating main operation.

Means for solving the problems

The air conditioner of the present disclosure includes a refrigerant circuit and a blower. The refrigerant circuit includes a compressor, a refrigerant flow path switching mechanism, an outdoor heat exchanger, a first expansion valve, a reheater, a second expansion valve, and a cooler, and is configured to circulate a refrigerant. The blower is configured to blow air to the reheater and the cooler. The refrigerant flow path switching mechanism is configured to be switchable between a first switching state and a second switching state. The refrigerant flow switching mechanism is configured to be switched in the first switching state such that the refrigerant flows in the refrigerant circuit in the order of the compressor, the refrigerant flow switching mechanism, the outdoor heat exchanger, the first expansion valve, the refrigerant flow switching mechanism, the reheater, the second expansion valve, the cooler, and the refrigerant flow switching mechanism. The refrigerant flow switching mechanism is configured to be switched in the second switching state such that the refrigerant flows in the refrigerant circuit in the order of the compressor, the refrigerant flow switching mechanism, the reheater, the second expansion valve, the cooler, the refrigerant flow switching mechanism, the first expansion valve, the outdoor heat exchanger, and the refrigerant flow switching mechanism. The reheater and the cooler are configured such that the air blown by the blower passes through the reheater after passing through the cooler, both in the first switching state and in the second switching state.

Effects of the invention

According to the air conditioner of the present disclosure, the refrigerant flow path switching mechanism is configured to be switched such that the refrigerant flows in the refrigerant circuit in the order of the reheater and the cooler, both in the first switching state and in the second switching state. Therefore, the directions of the refrigerant flowing through the reheater and the cooler can be made the same in both the cooling main operation and the heating main operation.

Drawings

Fig. 1 is a refrigerant circuit diagram of the cooling main operation of the air conditioner according to embodiment 1.

Fig. 2 is a refrigerant circuit diagram of the heating body operation of the air conditioner according to embodiment 1.

Fig. 3 is a schematic diagram of a first switching state of a rotary six-way valve of the air conditioner according to embodiment 1.

Fig. 4 is a schematic diagram of a second switching state of the rotary six-way valve of the air conditioner according to embodiment 1.

Fig. 5 is a schematic diagram of a first switching state of a sliding six-way valve of the air conditioner according to embodiment 1.

Fig. 6 is a schematic diagram of a second switching state of the sliding six-way valve of the air conditioner according to embodiment 1.

Fig. 7 is a refrigerant circuit diagram of the cooling main operation of the air conditioner according to embodiment 2.

Fig. 8 is a refrigerant circuit diagram of the heating body operation of the air conditioner according to embodiment 2.

Fig. 9 is a refrigerant circuit diagram of the cooling main operation of the air conditioner according to embodiment 3.

Fig. 10 is a refrigerant circuit diagram of the heating body operation of the air conditioner according to embodiment 3.

Fig. 11 is a perspective view of a reheater of the air conditioner in embodiment 3.

Fig. 12 is a perspective view of a cooler of an air conditioner according to embodiment 3.

Fig. 13 is a perspective view of a reheater of the air conditioner in accordance with embodiment 4.

Fig. 14 is a perspective view of a cooler of an air conditioner according to embodiment 4.

Fig. 15 is a cross-sectional view of a fin of a reheater of an air conditioner in accordance with embodiment 4.

Detailed Description

Hereinafter, embodiments will be described with reference to the drawings. In the following, the same or corresponding parts are denoted by the same reference numerals, and the description thereof will not be repeated.

Embodiment 1.

The structure of an air conditioner 100 according to embodiment 1 will be described with reference to fig. 1.

< Device Structure >

Fig. 1 is a refrigerant circuit diagram of an air conditioner 100 according to embodiment 1. As shown in fig. 1, the air conditioner 100 includes a refrigerant circuit RC, a sensor 15, an air passage 31, a blower 32, and a control device CD. The refrigerant circuit RC includes a high-pressure pipe 1, a low-pressure pipe 2, a discharge pipe 3, a suction pipe 4, a gas pipe 5, a liquid pipe 6, a compressor 11, a refrigerant flow switching mechanism RF, an outdoor heat exchanger 13, a first expansion valve 14, a reheater 21, a cooler 22, and a second expansion valve 23.

In the refrigerant circuit RC, the compressor 11, the refrigerant flow switching mechanism RF, the outdoor heat exchanger 13, the first expansion valve 14, the reheater 21, the cooler 22, and the second expansion valve 23 are connected by a high-pressure pipe 1, a low-pressure pipe 2, a discharge pipe 3, a suction pipe 4, a gas pipe 5, and a liquid pipe 6.

The high-pressure pipe 1 is connected to the refrigerant flow switching mechanism RF and the reheater 21. The low-pressure pipe 2 is connected to the refrigerant flow switching mechanism RF and the cooler 22. The discharge pipe 3 is connected to the discharge side of the compressor 11 and the refrigerant flow switching mechanism RF. The suction pipe 4 is connected to a suction side of the compressor 11 and the refrigerant flow switching mechanism RF. The gas pipe 5 is connected to the refrigerant flow switching mechanism RF and the outdoor heat exchanger 13. The liquid pipe 6 is connected to the outdoor heat exchanger 13 and the refrigerant flow switching mechanism RF via the first expansion valve 14.

The refrigerant circuit RC is configured to circulate a refrigerant. The refrigerant is a mixed refrigerant. The mixed refrigerant is a mixture of two or more refrigerants. In addition, the refrigerant may be a single refrigerant.

The air conditioner 100 includes an outdoor unit 10 and an indoor unit 20. The outdoor unit 10 and the indoor unit 20 are connected by a high-pressure pipe 1 and a low-pressure pipe 2. The outdoor unit 10 includes a compressor 11, a refrigerant flow switching mechanism RF, an outdoor heat exchanger 13, a first expansion valve 14, a sensor 15, and a control device CD. The compressor 11, the refrigerant flow path switching mechanism RF, the outdoor heat exchanger 13, the first expansion valve 14, the sensor 15, and the control device CD are housed in the outdoor unit 10. The indoor unit 20 includes a reheater 21, a cooler 22, a second expansion valve 23, an air passage 31, and a blower 32. The reheater 21, the cooler 22, the second expansion valve 23, and the blower 32 are housed in the indoor unit 20. The indoor unit 20 is provided with an air duct 31.

The compressor 11 is configured to compress a refrigerant. The compressor 11 is configured to compress and discharge the sucked refrigerant. The compressor 11 is configured to have a variable capacity, for example. The compressor 11 is configured to change the capacity by adjusting the rotation speed of the compressor 11 based on an instruction from the control device CD, for example.

The refrigerant flow path switching mechanism RF is configured to be switchable between a first switching state and a second switching state. The refrigerant flow path switching mechanism RF is configured to switch between a first switching state and a second switching state, for example, based on an instruction from the control device CD. The refrigerant flow switching mechanism RF is configured to be switched in the first switching state such that the refrigerant flows in the refrigerant circuit RC in the order of the compressor 11, the refrigerant flow switching mechanism RF, the outdoor heat exchanger 13, the first expansion valve 14, the refrigerant flow switching mechanism RF, the reheater 21, the second expansion valve 23, the cooler 22, and the refrigerant flow switching mechanism RF. The refrigerant flow path switching mechanism RF is in a first switching state during the cooling main body operation.

The refrigerant flow switching mechanism RF is configured to be switched in the second switching state such that the refrigerant flows in the refrigerant circuit RC in the order of the compressor 11, the refrigerant flow switching mechanism RF, the reheater 21, the second expansion valve 23, the cooler 22, the refrigerant flow switching mechanism RF, the first expansion valve 14, the outdoor heat exchanger 13, and the refrigerant flow switching mechanism RF. The refrigerant flow path switching mechanism RF is in the second switching state during the heating main body operation.

In embodiment 1, the refrigerant flow path switching mechanism RF is a six-way valve 12. The six connection ports (first connection port P1 to sixth connection port P6) of the six-way valve 12 are connected to the high-pressure pipe 1, the low-pressure pipe 2, the discharge pipe 3, the suction pipe 4, the gas pipe 5, and the liquid pipe 6, respectively. The first connection port P1 is connected to the discharge pipe 3. The second connection port P2 is connected to the gas pipe 5. The third connection port P3 is connected to the suction pipe 4. The fourth connection port P4 is connected to the low-pressure pipe 2. The fifth connection port P5 is connected to the liquid pipe 6. The sixth connection port P6 is connected to the high-pressure pipe 1.

In the first switching state of the six-way valve 12, a refrigerant circuit RC is formed in which the refrigerant reaches the compressor 11 again through the compressor 11, the discharge pipe 3, the six-way valve 12, the gas pipe 5, the outdoor heat exchanger 13, the liquid pipe 6, the first expansion valve 14, the six-way valve 12, the high-pressure pipe 1, the reheater 21, the second expansion valve 23, the cooler 22, the low-pressure pipe 2, the six-way valve 12, and the suction pipe 4. In the first switching state of the six-way valve 12, the second connection port P2 is connected to the first connection port P1, the fourth connection port is connected to the third connection port P3, and the sixth connection port is connected to the fifth connection port.

In the second switching state of the six-way valve 12, a refrigerant circuit RC is formed which reaches the compressor 11 again through the compressor 11, the discharge pipe 3, the six-way valve 12, the high-pressure pipe 1, the reheater 21, the second expansion valve 23, the cooler 22, the low-pressure pipe 2, the six-way valve 12, the first expansion valve 14, the liquid pipe 6, the outdoor heat exchanger 13, the gas pipe 5, the six-way valve 12, and the suction pipe 4. In the second switching state of the six-way valve 12, the sixth connection port P6 is connected to the first connection port P1, the third connection port P3 is connected to the second connection port P2, and the fifth connection port P5 is connected to the fourth connection port P4.

The outdoor heat exchanger 13 is configured to exchange heat between the refrigerant flowing inside the outdoor heat exchanger 13 and the air flowing outside the outdoor heat exchanger 13. The outdoor heat exchanger 13 is configured to function as a condenser for condensing the refrigerant in the cooling main operation and the cooling operation. The outdoor heat exchanger 13 is configured to function as an evaporator for evaporating the refrigerant in the heating main operation and the heating operation. The outdoor heat exchanger 13 is, for example, a fin-and-tube heat exchanger having a plurality of fins and a heat transfer tube penetrating the plurality of fins.

The first expansion valve 14 is configured to decompress the refrigerant condensed by the condenser by expanding the refrigerant. In the cooling main operation and the heating main operation, the first expansion valve 14 is in the fully opened state and does not function as a pressure reducing device. The first expansion valve 14 is configured to decompress the refrigerant condensed by the outdoor heat exchanger 13 during the cooling operation. The first expansion valve 14 is configured to decompress the refrigerant condensed by the reheater 21 and the cooler 22 during the heating operation.

The first expansion valve 14 is, for example, a solenoid expansion valve. The first expansion valve 14 is configured to change the amount of pressure reduction by adjusting the opening degree of the first expansion valve 14 based on an instruction from the control device CD, for example.

The sensor 15 is provided in the refrigerant circuit RC between the first expansion valve 14 and the refrigerant flow switching mechanism RF. The sensor 15 is provided in a pipe connecting the first expansion valve 14 and the refrigerant flow switching mechanism RF. The sensor 15 is configured to be able to measure the pressure or temperature of the refrigerant in the pipe. The sensor 15 is configured to be able to measure the pressure or temperature of the refrigerant in the refrigerant circuit RC. The sensor 15 may be a refrigerant pressure sensor configured to be able to measure the pressure of the refrigerant, or may be a refrigerant temperature sensor configured to be able to measure the temperature of the refrigerant.

The control device CD is configured to perform operations, instructions, and the like to control the respective devices and the like of the air conditioner 100. The control device CD is electrically connected to the compressor 11, the refrigerant flow switching mechanism RF, the first expansion valve 14, the sensor 15, the second expansion valve 23, the blower 32, and the like, and is configured to control the operations thereof.

The reheater 21 is configured to exchange heat between the refrigerant flowing inside the reheater 21 and the air flowing outside the reheater 21. The reheater 21 is configured to function as a condenser for condensing the refrigerant in the cooling main operation, the heating main operation, and the heating operation. The reheater 21 is configured to function as an evaporator that evaporates the refrigerant in the cooling operation. The reheater 21 is, for example, a fin-tube heat exchanger having a plurality of fins and a heat transfer tube penetrating the plurality of fins.

The cooler 22 is configured to exchange heat between the refrigerant flowing inside the cooler 22 and the air flowing outside the cooler 22. The cooler 22 is configured to function as an evaporator for evaporating the refrigerant in the cooling main operation, the heating main operation, and the cooling operation. The cooler 22 is configured to function as a condenser for condensing the refrigerant during the heating operation. The cooler 22 is, for example, a fin-tube heat exchanger having a plurality of fins and a heat transfer tube penetrating the plurality of fins.

The second expansion valve 23 is configured to decompress the refrigerant condensed by the condenser by expanding the refrigerant. The second expansion valve 23 is configured to decompress the refrigerant condensed by the reheater 21 in the cooling main operation and the heating main operation. In the cooling operation and the heating operation, the second expansion valve 23 is fully opened and does not function as a pressure reducing device. The second expansion valve 23 is, for example, an electromagnetic expansion valve. The second expansion valve 23 is configured to change the amount of pressure reduction by adjusting the opening degree of the second expansion valve 23 based on an instruction from the control device CD, for example.

The air duct 31 is provided in the casing of the indoor unit 20. The reheater 21 and the cooler 22 are disposed in the air duct 31. The blower 32 is configured to blow air to the reheater 21 and the cooler 22. The reheater 21 and the cooler 22 are arranged in the flow direction of the air blown by the blower 32. The reheater 21 is disposed downstream of the cooler 22 in the flow of the air blown by the blower 32. In the air passage 31, the cooler 22 is disposed upstream of the reheater 21.

The reheater 21 and the cooler 22 share the air passage 31 and the blower 32. The reheater 21 and the cooler 22 are configured such that the air blown by the blower 32 passes through the reheater 21 after passing through the cooler 22, both in the first switching state and in the second switching state. The reheater 21 and the cooler 22 are configured such that, during operation of the blower 32, air passes through the reheater 21 after passing through the cooler 22, regardless of the first switching state and the second switching state of the six-way valve 12.

The reheater 21 and the cooler 22 may be configured such that the flow of the refrigerant is opposite to the flow of the air. Both the reheater 21 and the cooler 22 have a heat transfer pipe flow path structure in which air and refrigerant flow in opposite directions. The reheater 21 and the cooler 22 have a heat transfer pipe on the upwind side and a heat transfer pipe on the downwind side, respectively. The heat transfer pipe on the windward side is connected with the heat transfer pipe on the leeward side. In the cooling main operation and the heating main operation, the refrigerant flows from the heat transfer pipe on the leeward side to the heat transfer pipe on the upwind side. In both the cooling main operation and the heating main operation, the refrigerant flowing through the heat transfer tubes of the reheater 21 and the cooler 22 and the air flowing through the outside of the heat transfer tubes are in opposite flows.

Next, the operation of the air conditioner 100 according to embodiment 1 will be described.

< Operation of Cooling body >

First, the cooling main operation of the air conditioner 100 according to embodiment 1 will be described with reference to fig. 1. The cooling main operation is an operation in which the cooling amount of air in the cooler 22 is larger than the heating amount of air in the reheater 21, and the outdoor heat exchanger 13 functions as a condenser, thereby radiating heat to the outside air as the remaining heat radiation amount of the heat pump. In the cooling main operation, the air passing through the reheater 21 has a lower temperature and a lower moisture content than the air before passing through the cooler 22.

In the cooling main operation, as shown by the solid line in fig. 1, the six-way valve 12 is switched to the first switching state. The vapor refrigerant compressed to a high temperature and a high pressure in the compressor 11 flows out to the discharge pipe 3, passes through the six-way valve 12, and flows into the outdoor heat exchanger 13 through the gas pipe 5. The outdoor heat exchanger 13 functions as a condenser. The high-temperature and high-pressure vapor refrigerant radiates heat to the outdoor air introduced into the outdoor heat exchanger 13 by an outdoor blower (not shown). Thereby, the high-temperature and high-pressure vapor refrigerant is condensed to become a high-temperature and high-pressure gas-liquid two-phase refrigerant.

The high-temperature and high-pressure gas-liquid two-phase refrigerant flows out to the liquid pipe 6, passes through the six-way valve 12 via the first expansion valve 14, and flows into the reheater 21 via the high-pressure pipe 1. The reheater 21 functions as a condenser. The high-temperature and high-pressure gas-liquid two-phase refrigerant radiates heat to the air introduced into the reheater 21 by the blower 32. Thereby, the high-temperature and high-pressure gas-liquid two-phase refrigerant is condensed to become a high-pressure liquid refrigerant. The high-pressure liquid refrigerant flows into the second expansion valve 23.

The high-pressure liquid refrigerant is expanded and decompressed in the second expansion valve 23, and becomes a low-temperature low-pressure gas-liquid two-phase refrigerant. The low-temperature low-pressure gas-liquid two-phase refrigerant flows into the cooler 22. The cooler 22 functions as an evaporator. By absorbing heat from the air introduced into the cooler 22 by the blower 32, the low-temperature low-pressure gas-liquid two-phase refrigerant evaporates, thereby becoming a low-pressure vapor refrigerant. Thereafter, the low-pressure vapor refrigerant flows into the six-way valve 12 through the low-pressure pipe 2, and is sucked into the compressor 11 through the suction pipe 4. In the cooling main operation, the refrigerant is next circulated in the refrigerant circuit RC in the same manner.

The reheater 21 and the cooler 22 share the air passage 31 and the blower 32. The air guided in the air passage 31 by the blower 32 is first cooled and dehumidified by the cooler 22. This reduces the temperature of the air, and reduces the moisture content of the air. The air having passed through the cooler 22 is guided by the air duct 31, passes through the reheater 21, and is heated. Thereby, the temperature of the air rises. Since humidification is not generally performed in the reheater 21, the moisture content of the air does not change before and after passing through the reheater 21. The air having passed through the reheater 21 is guided by the duct 31 and blown out into the space to be air-conditioned.

The air is cooled and dehumidified by the cooler 22 and then heated by the reheater 21 as necessary, so that the amount of dehumidification of the air and the temperature of the air can be independently adjusted. Therefore, the air of the temperature and humidity set by the user can be supplied to the space to be air-conditioned.

< Operation of heating body >

Next, the heating main operation of the air conditioner 100 according to embodiment 1 will be described with reference to fig. 2. The heating main operation is an operation in which the heating amount of the air in the reheater 21 is larger than the cooling amount of the air in the cooler 22, and the outdoor heat exchanger 13 functions as an evaporator, thereby exhausting heat to the outside air as the remaining cooling heat amount of the heat pump. In the heating main operation, the air passing through the reheater 21 has a higher temperature and a lower moisture content than the air before passing through the cooler 22.

In the heating main operation, as shown by the solid line in fig. 2, the six-way valve 12 is switched to the second switching state. The vapor refrigerant compressed to a high temperature and a high pressure in the compressor 11 flows out to the discharge pipe 3, passes through the six-way valve 12, and flows into the reheater 21 via the high pressure pipe 1. The reheater 21 functions as a condenser. The high-temperature and high-pressure vapor refrigerant radiates heat to the air introduced into the reheater 21 by the blower 32. Thereby, the high-temperature and high-pressure vapor refrigerant is condensed to become a high-pressure liquid refrigerant. The high-pressure liquid refrigerant flows into the second expansion valve 23.

The high-pressure liquid refrigerant is expanded and decompressed in the second expansion valve 23, and becomes a low-temperature low-pressure gas-liquid two-phase refrigerant. The low-temperature low-pressure gas-liquid two-phase refrigerant flows into the cooler 22. The cooler 22 functions as an evaporator. By absorbing heat from the air introduced into the cooler 22 by the blower 32, a part of the low-temperature low-pressure gas-liquid two-phase refrigerant evaporates. Thereafter, the low-temperature low-pressure gas-liquid two-phase refrigerant flows into the six-way valve 12 through the low-pressure pipe 2, flows out into the liquid pipe 6, and flows into the outdoor heat exchanger 13 through the first expansion valve 14.

The outdoor heat exchanger 13 functions as an evaporator. The low-temperature low-pressure gas-liquid two-phase refrigerant evaporates by absorbing heat from the outdoor air introduced into the outdoor heat exchanger 13 by an outdoor blower (not shown), thereby becoming a low-pressure vapor refrigerant. The low-pressure vapor refrigerant flows into the six-way valve 12 through the gas pipe 5, and is sucked into the compressor 11 through the suction pipe 4. In the heating main operation, the refrigerant is next circulated in the refrigerant circuit RC in the same manner.

The air guided in the air passage 31 by the blower 32 is cooled and dehumidified by the cooler 22, and then heated by the reheater 21, and blown out into the space to be air-conditioned, as in the cooling main operation. Therefore, the amount of dehumidification of the air and the temperature of the air can be independently adjusted, respectively. Therefore, the air of the temperature and humidity set by the user can be supplied to the space to be air-conditioned.

< Cooling operation >

The cooling operation will be described with reference to fig. 1 again. In the cooling operation, the first expansion valve 14 expands the refrigerant. That is, in the cooling operation, the first expansion valve 14 functions as an expansion valve. On the other hand, during the cooling operation, the second expansion valve 23 is in the fully opened state and does not function as an expansion valve.

In the cooling operation, the refrigerant circulates through the refrigerant circuit RC in the order of the compressor 11, the refrigerant flow switching mechanism RF, the outdoor heat exchanger 13, the first expansion valve 14, the refrigerant flow switching mechanism RF, the reheater 21, the second expansion valve 23, the cooler 22, and the refrigerant flow switching mechanism RF.

< Heating operation >

The heating operation will be described with reference to fig. 2 again. In the heating operation, the first expansion valve 14 expands the refrigerant. That is, during the heating operation, the first expansion valve 14 functions as an expansion valve. On the other hand, during the heating operation, the second expansion valve 23 is in the fully opened state and does not function as an expansion valve.

In the heating operation, the refrigerant circulates in the refrigerant circuit RC in the order of the compressor 11, the refrigerant flow switching mechanism RF, the reheater 21, the second expansion valve 23, the cooler 22, the refrigerant flow switching mechanism RF, the first expansion valve 14, the outdoor heat exchanger 13, and the refrigerant flow switching mechanism RF.

Next, the operational effects of the air conditioner 100 according to embodiment 1 will be described.

According to the air conditioner of embodiment 1, the refrigerant flow path switching mechanism RF is configured to be switched such that the refrigerant flows in the refrigerant circuit RC in the order of the reheater 21 and the cooler 22, both in the first switching state and in the second switching state. The refrigerant flow path switching mechanism RF is set to a first switching state during the cooling main operation and to a second switching state during the heating main operation. Therefore, the directions of the refrigerant flowing through the reheater 21 and the cooler 22 can be made the same in both the cooling main operation and the heating main operation.

The reheater 21 and the cooler 22 are configured such that the air blown by the blower 32 passes through the reheater 21 after passing through the cooler 22, both in the first switching state and in the second switching state. Therefore, in both the cooling main operation and the heating main operation, the air can be reheated after being cooled and dehumidified. Therefore, sufficient dehumidification can be performed in both the cooling main operation and the heating main operation.

In particular, since sufficient dehumidification can be performed during the heating main operation, the heating main operation can be used for drying and dehumidifying the air-conditioning target space. Therefore, the air conditioner 100 according to embodiment 1 can be used for drying food and materials.

In the air conditioner 100 according to embodiment 1, the refrigerant flow switching mechanism RF is the six-way valve 12. Therefore, the flow direction of the refrigerant flowing in the reheater 21 and the cooler 22 can be made the same, both in the cooling main operation and in the heating main operation. Therefore, the reheater 21 can heat the air cooled and dehumidified by the cooler 22, both during the cooling main operation and during the heating main operation. Therefore, the air of the temperature and humidity set by the user can be supplied to the space to be air-conditioned.

When noise, vibration, and the like in the indoor space are not desired, it is preferable to provide the compressor 11 in the outdoor unit 10 as compared with the structure of the air conditioner 100 called the remote control type in which the compressor 11 is provided in the indoor unit 20. In the long range, the following refrigerant circuit structure is typical: one end of the reheater 21 is connected to the discharge pipe 3 without passing through the refrigerant flow switching mechanism RF, and the other end of the reheater 21 is connected to the liquid pipe 6. In this refrigerant circuit configuration, if a separate configuration is adopted in which the compressor 11 is provided in the outdoor unit 10, it is necessary to connect the outdoor unit 10 and the indoor unit 20 by three pipes, i.e., the discharge pipe 3, the liquid pipe 6, and the low-pressure pipe 2. In the configuration of the air conditioner 100 according to embodiment 1, the outdoor unit 10 and the indoor unit 20 are connected by the high-pressure pipe 1 and the low-pressure pipe 2. Therefore, the outdoor unit 10 and the indoor unit 20 can be connected by two pipes, i.e., the high-pressure pipe 1 and the low-pressure pipe 2, and thus the labor for construction can be reduced.

According to the air conditioner 100 of embodiment 1, the sensor 15 is configured to be able to measure the pressure or temperature of the refrigerant in the refrigerant circuit RC. Therefore, during the cooling main operation, the first expansion valve 14 can adjust the heating amount of the air based on the result of the sensor 15 measuring the pressure or temperature of the refrigerant in the reheater 21. In the heating main operation, the first expansion valve 14 can adjust the cooling amount of the air based on the result of the sensor 15 measuring the pressure or temperature of the refrigerant in the cooler 22. Therefore, the refrigerant condensation temperature in the reheater 21 can be finely adjusted in the cooling main operation, and the refrigerant evaporation temperature in the cooler 22 can be finely adjusted in the heating main operation. This enables stable control of the temperature and humidity of the blown air of the air conditioner 100.

Specifically, for example, when the refrigerant pressure value in the reheater 21 in the cooling main operation or the refrigerant pressure value in the cooler 22 in the heating main operation corresponding to the temperature and humidity of the air blown out by the air conditioner 100 set by the user is clear in advance, the opening command of the first expansion valve 14 is adjusted so that the measured value of the sensor 15 approaches the refrigerant pressure value.

According to the air conditioner 100 of embodiment 1, the refrigerant is a mixed refrigerant. Since a mixture of two or more refrigerants, i.e., a mixed refrigerant, is generally a non-azeotropic refrigerant, the temperature at the time of gas-liquid phase change is not constant. Thus, a temperature gradient is generated in the heat exchanger as the mixed refrigerant changes phase. Therefore, an optimal design of the heat exchanger is required. In the air conditioner 100 according to embodiment 1, since the reheater 21 and the cooler 22 can be specially designed, the air conditioner 100 with high performance can be realized even when the mixed refrigerant is used.

According to the air conditioner 100 of embodiment 1, the reheater 21 and the cooler 22 are configured such that the flow of the refrigerant is opposite to the flow of the air. Therefore, the temperature gradient in the heat exchanger of the mixed refrigerant can be used to reduce the heat exchange temperature difference between the air and the refrigerant. Therefore, high-performance operation of the air conditioner 100 can be achieved.

Since the temperature of the zeotropic refrigerant increases with the evaporation of the refrigerant, the temperature increase in the flow direction of the refrigerant and the temperature decrease in the flow direction of the air interact with each other by the structure in which the air and the refrigerant are caused to flow in the opposite direction in the cooler 22 functioning as an evaporator, and thus the heat exchange temperature difference between the air and the refrigerant can be reduced in the entire region of the cooler 22.

Further, since the temperature of the zeotropic refrigerant decreases with the condensation of the refrigerant, the temperature decrease in the flow direction of the refrigerant and the temperature increase in the flow direction of the air interact with each other by the structure in which the air and the refrigerant are caused to flow in the counter flow in the reheater 21 functioning as a condenser, and thus the heat exchange temperature difference between the air and the refrigerant can be reduced in the entire area of the reheater 21.

The position of the blower 32 is not limited to the upstream of the air passage 31 of the cooler 22 as shown in fig. 1 and 2. The blower 32 may be located between the cooler 22 and the reheater 21 in the air passage 31, or downstream of the air passage 31 of the reheater 21.

Referring to fig. 3 and 4, the six-way valve 12 may be configured to rotate. Fig. 3 is a schematic diagram of a first switching state of the rotary six-way valve 12. Fig. 4 is a schematic diagram of the second switching state of the rotary six-way valve 12. The rotary six-way valve 12 includes a valve seat 12a and a valve body 12b configured to be rotatable with respect to the valve seat 12 a. The flow path is switched between the first switching state and the second switching state by rotation of the valve body 12b relative to the valve seat 12 a.

Referring to fig. 5 and 6, the six-way valve 12 may have a sliding type structure. Fig. 5 is a schematic diagram of the first switching state of the sliding six-way valve 12. Fig. 6 is a schematic diagram of the second switching state of the sliding six-way valve 12. The sliding six-way valve 12 includes a valve seat 12a and a valve body 12b configured to be slidable with respect to the valve seat 12 a. By sliding the valve body 12b relative to the valve seat 12a, the flow path is switched between the first switching state and the second switching state.

Embodiment 2.

The air conditioner 100 according to embodiment 2 has the same structure, operation, and effects as those of the air conditioner 100 according to embodiment 1 unless otherwise specified.

< Device Structure >

Fig. 7 is a refrigerant circuit diagram of the air conditioner 100 according to embodiment 2. The configuration of the air conditioner 100 according to embodiment 2 will be described with reference to fig. 7.

In embodiment 2, the refrigerant flow path switching mechanism RF has the four-way valve 41 and the check valve bridge circuit NC. The four-way valve 41 is connected to the compressor 11, the outdoor heat exchanger 13, and the check valve bridge circuit NC. The check valve bridge circuit NC has a first check valve 42, a second check valve 43, a third check valve 44, and a fourth check valve 45.

The four connection ports (first connection port P1 to fourth connection port P4) of the four-way valve 41 are connected to the high-pressure pipe 1, the low-pressure pipe 2, the discharge pipe 3, the suction pipe 4, and the gas pipe 5, respectively. The first connection port P1 is connected to the discharge pipe 3. The second connection port P2 is connected to the gas pipe 5. The third connection port P3 is connected to the inflow port of the first check valve 42 and the outflow port of the fourth check valve 45. The fourth connection port P4 is connected to the suction pipe 4.

The outflow port of the first check valve 42 and the outflow port of the third check valve 44 are connected to the high-pressure pipe 1. An inflow port of the fourth check valve 45 and an inflow port of the second check valve 43 are connected to the low-pressure pipe 2. The outflow port of the second check valve 43 and the inflow port of the third check valve 44 are connected to the liquid pipe 6.

In the first switching state of the four-way valve 41, a refrigerant circuit RC is configured such that the refrigerant reaches the compressor 11 again through the compressor 11, the discharge pipe 3, the four-way valve 41, the gas pipe 5, the outdoor heat exchanger 13, the liquid pipe 6, the first expansion valve 14, the third check valve 44, the high-pressure pipe 1, the reheater 21, the second expansion valve 23, the cooler 22, the low-pressure pipe 2, the fourth check valve 45, the four-way valve 41, and the suction pipe 4. In the first switching state of the four-way valve 41, the second connection port P2 is connected to the first connection port P1, and the fourth connection port is connected to the third connection port P3.

In the second switching state of the four-way valve 41, a refrigerant circuit RC is formed in which the refrigerant reaches the compressor 11 again through the compressor 11, the discharge pipe 3, the four-way valve 41, the first check valve 42, the high-pressure pipe 1, the reheater 21, the second expansion valve 23, the cooler 22, the low-pressure pipe 2, the second check valve 43, the first expansion valve 14, the liquid pipe 6, the outdoor heat exchanger 13, the gas pipe 5, the four-way valve 41, and the suction pipe 4. In the second switching state of the four-way valve 41, the third connection port P3 is connected to the first connection port P1, and the fourth connection port P4 is connected to the second connection port P2.

Next, the operation of the air conditioner 100 according to embodiment 2 will be described.

The operation of the air conditioner 100 according to embodiment 2 is basically the same as that of embodiment 1. Referring to fig. 7, in the cooling main operation of the air conditioner 100 according to embodiment 2, the refrigerant flows into the compressor 11 again through the compressor 11, the discharge pipe 3, the four-way valve 41, the gas pipe 5, the outdoor heat exchanger 13, the liquid pipe 6, the first expansion valve 14, the third check valve 44, the high-pressure pipe 1, the reheater 21, the second expansion valve 23, the cooler 22, the low-pressure pipe 2, the fourth check valve 45, the four-way valve 41, and the suction pipe 4 in the refrigerant circuit RC.

Referring to fig. 8, in the heating main operation of the air conditioner 100 according to embodiment 2, the refrigerant flows again to the compressor 11 through the compressor 11, the discharge pipe 3, the four-way valve 41, the first check valve 42, the high-pressure pipe 1, the reheater 21, the second expansion valve 23, the cooler 22, the low-pressure pipe 2, the second check valve 43, the first expansion valve 14, the liquid pipe 6, the outdoor heat exchanger 13, the gas pipe 5, the four-way valve 41, and the suction pipe 4 in the refrigerant circuit RC.

Referring again to fig. 7, in the cooling operation of the air conditioner 100 according to embodiment 2, the refrigerant flows through the refrigerant circuit RC in the same manner as in the cooling main operation. Referring again to fig. 8, in the heating operation of the air conditioner 100 according to embodiment 2, the refrigerant flows through the refrigerant circuit RC in the same manner as in the heating main operation.

Next, the operational effects of the air conditioner 100 according to embodiment 2 will be described.

In the air conditioner 100 according to embodiment 2, the refrigerant flow switching mechanism RF includes a four-way valve 41 and a check valve bridge circuit NC. Therefore, the direction of the refrigerant flowing through the reheater 21 and the cooler 22 can be made the same, both in the cooling main operation and in the heating main operation. Therefore, the reheater 21 can heat the air cooled and dehumidified by the cooler 22, both during the cooling main operation and during the heating main operation. Therefore, the air of the temperature and humidity set by the user can be supplied to the space to be air-conditioned.

Further, the four-way valve 41 and the check valve bridge circuit NC can constitute the refrigerant flow switching mechanism RF, and therefore the refrigerant flow switching mechanism RF can be constituted by inexpensive components.

Embodiment 3.

The air conditioner 100 of embodiment 3 has the same structure, operation, and effects as those of the air conditioner 100 of embodiment 1 unless otherwise specified.

The structure of the air conditioner 100 according to embodiment 3 will be described with reference to fig. 9 and 10.

As shown in fig. 9 and 10, the reheater 21 has a plurality of first heat transfer passages T1 arranged in parallel. The cooler 22 has a plurality of second heat transfer flow paths T2 arranged in parallel.

Referring to fig. 11 and 12, the number of parallel second heat transfer passages T2 of the cooler 22 is larger than the number of parallel first heat transfer passages T1 of the reheater 21. The parallel number is the branch number. In other words, the parallel number is the number of passes.

Next, the operational effects of the air conditioner 100 according to embodiment 3 will be described.

The refrigerant in the reheater 21 is in a high-temperature and high-pressure state, and has a high density. Therefore, by reducing the number of parallel first heat transfer channels T1, the refrigerant flow rate can be increased to increase the heat transfer rate in the heat transfer channels. Therefore, reducing the number of parallel connections of the first heat transfer flow path T1 contributes to improving the performance of the air conditioner 100.

The refrigerant in the cooler 22 is in a low-temperature and low-pressure state, and has a low density. Therefore, by increasing the number of parallel second heat transfer channels T2, the refrigerant flow rate can be reduced, and the pressure loss in the heat transfer channels can be reduced. Therefore, increasing the number of parallel connection of the second heat transfer flow paths T2 contributes to improvement in performance of the air conditioner 100.

Therefore, according to the air conditioner 100 of embodiment 3, the number of parallel connection of the plurality of second heat transfer channels T2 of the cooler 22 is larger than the number of parallel connection of the plurality of first heat transfer channels T1 of the reheater 21, and therefore, the high-performance air conditioner 100 can be realized.

The heat exchanger on the upstream side of the air passage is a cooler 22, and the heat exchanger on the downstream side of the air passage is a reheater 21, and thus, from the viewpoint of designing the number of parallel branches of the heat transfer tubes in the heat exchanger, it is possible to optimally design the effect of performance improvement due to the improvement in heat transfer rate of the refrigerant and the effect of performance improvement due to the reduction in pressure loss of the refrigerant.

Embodiment 4.

The air conditioner 100 of embodiment 4 has the same structure, operation, and effects as those of the air conditioner 100 of embodiment 1 unless otherwise specified.

The configuration of the reheater 21 and the cooler 22 of the air conditioner 100 according to embodiment 4 will be described with reference to fig. 13 to 15.

As shown in fig. 13, the reheater 21 has a first fin F1. The reheater 21 may have a plurality of first fins F1. As shown in fig. 14, the cooler 22 has second fins. The cooler 22 may also have a plurality of second fins F2. The contact angle with water at the surface of the second fin F2 of the cooler 22 is smaller than the contact angle with water at the surface of the first fin F1 of the reheater 21.

As shown in fig. 15, the surface of the second fin F2 of the cooler 22, on which condensation occurs due to cooling of air, is preferably subjected to hydrophilic treatment in order to suppress scattering of condensation water into the air passage and to improve drainage of the fin surface. The second fin F2 of the cooler 22 has a main body portion Fa and a hydrophilic treatment portion Fb covering the surface of the main body portion Fa. On the other hand, dew condensation water is not generated on the fin surfaces of the reheater 21, and thus, it is not necessary to perform a costly hydrophilic treatment.

Next, the operational effects of the air conditioner 100 according to embodiment 4 will be described.

According to the air conditioner 100 of embodiment 4, the contact angle with water at the surface of the second fin F2 of the cooler 22 is smaller than the contact angle with water at the surface of the first fin F1 of the reheater 21. Therefore, the air conditioner 100 can be realized which combines dehumidification performance and cost.

Since the cooler 22 is used as the heat exchanger on the upstream side of the air passage and the reheater 21 is used as the heat exchanger on the downstream side of the air passage, the contact angle of water on the surface of the second fin F2 of the cooler 22 can be reduced as compared with the surface of the first fin F1 of the reheater 21 by, for example, performing hydrophilic treatment only on the fin surface of the cooler 22.

The presently disclosed embodiments are considered in all respects to be illustrative and not restrictive. The scope of the present disclosure is indicated by the claims rather than by the foregoing description, and all changes that come within the meaning and range of equivalency of the claims are intended to be embraced therein.

Description of the reference numerals

1: High-pressure piping, 2: low-pressure piping, 3: discharge piping, 4: suction pipe, 5: gas piping, 6: liquid piping, 10: outdoor unit, 11: compressor, 12: six-way valve, 13: outdoor heat exchanger, 14: first expansion valve, 15: sensor, 20: indoor unit, 21: reheater, 22: cooler, 23: second expansion valve, 31: wind path, 32: blower, 41: four-way valve, 42: first check valve, 43: second check valve, 44: third check valve, 45: fourth check valve, 100: air conditioner, F1: first fin, F2: second fin, NC: check valve bridge circuit, RC: refrigerant circuit, RF: refrigerant flow path switching mechanism, T1: first heat transfer flow path, T2: and a second heat transfer flow path.

Claims (9)

1. An air conditioner is provided with:

a refrigerant circuit configured to circulate a refrigerant, the refrigerant circuit including a compressor, a refrigerant flow path switching mechanism, an outdoor heat exchanger, a first expansion valve, a reheater, a second expansion valve, and a cooler; and

A blower configured to blow air to the reheater and the cooler,

The refrigerant flow path switching mechanism is configured to be switchable between a first switching state and a second switching state,

The refrigerant flow switching mechanism is configured to be switched in the first switching state such that the refrigerant flows in the refrigerant circuit in the order of the compressor, the refrigerant flow switching mechanism, the outdoor heat exchanger, the first expansion valve, the refrigerant flow switching mechanism, the reheater, the second expansion valve, the cooler, and the refrigerant flow switching mechanism, and

The refrigerant flow switching mechanism is configured to be switched in the second switching state such that the refrigerant flows in the refrigerant circuit in the order of the compressor, the refrigerant flow switching mechanism, the reheater, the second expansion valve, the cooler, the refrigerant flow switching mechanism, the first expansion valve, the outdoor heat exchanger, and the refrigerant flow switching mechanism,

The reheater and the cooler are configured such that the air blown by the blower passes through the reheater after passing through the cooler, both in the first switching state and in the second switching state.

2. The air conditioner according to claim 1, wherein,

The refrigerant flow path switching mechanism is a six-way valve.

3. The air conditioner according to claim 1, wherein,

The refrigerant flow path switching mechanism has a four-way valve and a check valve bridge circuit,

The four-way valve is connected with the compressor, the outdoor heat exchanger and the check valve bridge circuit.

4. The air conditioner according to any one of claim 1 to 3, wherein,

The reheater has a plurality of first heat transfer circuits arranged in parallel,

The cooler has a plurality of second heat transfer flow paths arranged in parallel,

The number of parallel connection of the plurality of second heat transfer flow paths of the cooler is greater than the number of parallel connection of the plurality of first heat transfer flow paths of the reheater.

5. The air conditioner according to any one of claims 1 to 4, wherein,

The reheater has a first fin and,

The cooler is provided with a second fin which,

The contact angle with water at the surface of the second fin of the cooler is less than the contact angle with water at the surface of the first fin of the reheater.

6. The air conditioner according to any one of claims 1 to 5, wherein,

The air conditioner further comprises:

an outdoor unit having the compressor and the outdoor heat exchanger;

An indoor unit having the reheater and the cooler;

High-pressure piping; and

A low-pressure piping is arranged in the pipeline,

The outdoor unit and the indoor unit are connected by the high-pressure pipe and the low-pressure pipe.

7. The air conditioner according to any one of claims 1 to 6, wherein,

A sensor is further provided in a pipe connecting the first expansion valve and the refrigerant flow switching mechanism,

The sensor is configured to be able to measure the pressure or temperature of the refrigerant in the piping.

8. The air conditioner according to any one of claims 1 to 7, wherein,

The refrigerant is a mixed refrigerant.

9. The air conditioner according to claim 8, wherein,

The reheater and the cooler are configured such that the flow of the refrigerant is counter-current to the flow of the air.