CN114623508A - Air conditioner - Google Patents

Abstract

Provided is an air conditioner which can save energy. An air conditioner according to one embodiment includes an indoor heat exchanger, an outdoor heat exchanger, 1 st and 2 nd pipes, a compressor, a four-way valve, 1 st and 2 nd expansion valves, a heat storage material, and a 1 st heat transfer unit. The 1 st and 2 nd pipes connect the indoor heat exchanger and the outdoor heat exchanger. The compressor and the four-way valve are provided in the 1 st pipe. The 1 st expansion valve is provided in the 2 nd pipe. The heat storage material is connected to the 1 st pipe between the indoor heat exchanger and the four-way valve and/or between the four-way valve and the compressor. The 2 nd expansion valve is provided in the 1 st pipe between the heat storage material and the compressor. The 1 st heat transfer unit is connected to the 1 st pipe between the 2 nd expansion valve and the compressor, and is connected to the 2 nd pipe between the outdoor heat exchanger and the 1 st expansion valve.

Description

Air conditioner

Technical Field

Embodiments of the present invention relate to an air conditioner.

Background

An air conditioner such as an air conditioner adjusts the temperature of the room by condensing and evaporating a refrigerant in a refrigeration cycle. For example, during a cooling operation, the refrigerant is condensed in the outdoor heat exchanger and evaporated in the indoor heat exchanger.

Patent document 1: japanese patent No. 6188932

Disclosure of Invention

When the outside air temperature is high during the cooling operation, the efficiency of heat exchange in the outdoor heat exchanger decreases, and the sensible heat load of the indoor heat exchanger increases due to radiant heat. Therefore, the indoor temperature is less likely to decrease, and the energy saving performance of the air conditioner is reduced.

An example of the problem to be solved by the present invention is to provide an air conditioner capable of saving energy.

An air conditioner according to an embodiment of the present invention includes an indoor heat exchanger, an outdoor heat exchanger, a 1 st pipe, a 2 nd pipe, a compressor, a four-way valve, a 1 st expansion valve, a heat storage material, a 2 nd expansion valve, and a 1 st heat transfer portion. The 1 st pipe connects the indoor heat exchanger and the outdoor heat exchanger to flow a refrigerant. The 2 nd pipe connects the outdoor heat exchanger and the indoor heat exchanger, and a refrigerant flows therethrough. The compressor is provided in the 1 st pipe, and has a suction port through which the refrigerant is sucked and a discharge port through which the refrigerant is discharged. The four-way valve is provided in the 1 st pipe, and is capable of changing a direction in which the refrigerant flows. The 1 st expansion valve is provided in the 2 nd pipe. The heat storage material is thermally connected to the 1 st pipe at least one of between the indoor heat exchanger and the four-way valve and between the four-way valve and the suction port of the compressor. The 2 nd expansion valve is provided in the 1 st pipe between the four-way valve and the suction port of the compressor and between the heat storage material and the suction port of the compressor. The 1 st heat transfer unit is thermally connected to the 1 st pipe between the 2 nd expansion valve and the suction port of the compressor, and is thermally connected to the 2 nd pipe between the outdoor heat exchanger and the 1 st expansion valve.

In the air conditioner, the heat storage material is thermally connected to the 1 st pipe between the indoor heat exchanger and the four-way valve, and is thermally connected to the 1 st pipe between the four-way valve and the suction port of the compressor.

The air conditioner further includes a 3 rd pipe, a switching valve, and a 2 nd heat transfer unit. One end of the 3 rd pipe is connected to the 1 st pipe between the 2 nd expansion valve and the 1 st heat transfer portion, and the other end is connected to the 1 st pipe between the 1 st heat transfer portion and the suction port of the compressor. The switching valve is provided at a connection portion between the one end of the 3 rd pipe and the 1 st pipe, and is capable of changing a direction in which the refrigerant flows. The 2 nd heat transfer portion is thermally connected to the 3 rd pipe, and is thermally connected to the 2 nd pipe between the indoor heat exchanger and the 1 st expansion valve.

The air conditioner further includes an indoor air supply fan and a control device. The indoor blowing fan generates an air flow which exchanges heat with the indoor heat exchanger. The control device controls the four-way valve, the 1 st expansion valve, the 2 nd expansion valve, and the indoor air supply fan. The control device can execute: a cooling operation in which the four-way valve is controlled so that the refrigerant flows from the discharge port of the compressor to the outdoor heat exchanger; and a cold storage operation in which the four-way valve is controlled so that the refrigerant flows from the discharge port of the compressor to the outdoor heat exchanger, the 1 st expansion valve and the indoor air-sending fan are controlled so that the refrigerant discharged from the indoor heat exchanger contains more liquid than gas, and the 2 nd expansion valve is controlled so that the refrigerant having transferred heat to the 1 st heat transfer unit is vaporized.

The air conditioner further includes an indoor unit temperature sensor and a heat storage material temperature sensor. The indoor unit temperature sensor detects a temperature of the refrigerant flowing through the indoor heat exchanger. The heat storage material temperature sensor detects the temperature of the heat storage material. The control device controls the opening degree of the 1 st expansion valve based on a difference between the temperature detected by the indoor unit temperature sensor and the temperature detected by the heat storage material temperature sensor during the cooling operation.

The air conditioner further includes a control device. The control device controls the four-way valve, the 1 st expansion valve, and the 2 nd expansion valve. The controller may be configured to perform a heating operation in which the four-way valve is controlled so that the refrigerant flows from the discharge port of the compressor to the indoor heat exchanger, and the 1 st expansion valve is controlled so that the refrigerant discharged from the indoor heat exchanger contains more gas than liquid.

According to the air conditioner described above, for example, energy saving of the air conditioner can be achieved.

Drawings

Fig. 1 is a refrigerant system diagram schematically showing an air conditioner in a cooling operation according to an embodiment.

Fig. 2 is a schematic diagram showing a refrigerant system of the air conditioner during the heating operation according to the above embodiment.

Fig. 3 is a block diagram functionally showing the configuration of the air conditioner according to the above embodiment.

Fig. 4 is a flowchart illustrating an example of the cooling operation control of the air conditioner according to the above embodiment.

Fig. 5 is a flowchart showing an example of the cooling operation control of the air conditioner according to the above embodiment.

Fig. 6 is a flowchart showing an example of the heating operation control of the air conditioner according to the above embodiment.

Fig. 7 is a block diagram showing an example of a hardware configuration of the control device according to the above embodiment.

Description of the symbols

10: an air conditioner; 14: a control device; 21: an outdoor heat exchanger; 23: a compressor; 23 a: a suction inlet; 23 b: an outlet port; 25: a four-way valve; 31: 1 st expansion valve; 32: a 2 nd expansion valve; 33: a switching valve; 41: an indoor heat exchanger; 42: an indoor air supply fan; 51: a 1 st pipe; 52: a 2 nd pipe; 53: a 3 rd pipe; 61: 1 st heat storage material; 62: a 2 nd heat storage material; 63: the 3 rd heat storage material.

Detailed Description

An embodiment will be described below with reference to fig. 1 to 7. In the present specification, the constituent elements of the embodiments and descriptions of the elements may be described in various ways. The constituent elements and their description are examples, and are not limited to the description of the present specification. The constituent elements may be identified by names different from those in the present specification. Further, the constituent elements may be described by expressions different from those of the present specification.

Fig. 1 is a refrigerant system diagram schematically showing an air conditioner 10 in a cooling operation according to an embodiment. The air conditioner 10 is, for example, a household air conditioner. The air conditioner 10 is not limited to this example, and may be another air conditioner such as a commercial air conditioner.

As shown in fig. 1, the air conditioner 10 includes an outdoor unit 11, an indoor unit 12, a refrigerant pipe 13, and a control device 14. The outdoor unit 11 is disposed outdoors, for example. The indoor unit 12 is disposed indoors, for example.

The air conditioner 10 includes a refrigeration cycle in which an outdoor unit 11 and an indoor unit 12 are connected by a refrigerant pipe 13. The refrigerant flows between the outdoor unit 11 and the indoor units 12 through the refrigerant pipes 13. The outdoor unit 11 and the indoor units 12 are electrically connected to each other by, for example, electric wiring.

The outdoor unit 11 includes an outdoor heat exchanger 21, an outdoor air-sending fan 22, a compressor 23, an accumulator 24, a four-way valve 25, a 1 st expansion valve 31, a 2 nd expansion valve 32, a switching valve 33, a 1 st check valve 34, and a 2 nd check valve 35. The indoor unit 12 includes an indoor heat exchanger 41 and an indoor air-sending fan 42.

The refrigerant pipe 13 is a pipe made of metal such as copper or aluminum, for example. The refrigerant pipe 13 includes a 1 st pipe 51, a 2 nd pipe 52, and a 3 rd pipe 53. The 1 st pipe 51 connects the indoor heat exchanger 41 and the outdoor heat exchanger 21. The compressor 23, the accumulator 24, the four-way valve 25, the 2 nd expansion valve 32, the switching valve 33, and the 1 st check valve 34 are provided in the 1 st pipe 51. The 2 nd pipe 52 connects the outdoor heat exchanger 21 and the indoor heat exchanger 41. The 1 st expansion valve 31 is provided in the 2 nd pipe 52. The 3 rd pipe 53 is connected to the 1 st pipe 51. The 2 nd check valve 35 is provided in the 3 rd pipe 53.

In the cooling operation, the refrigerant flows from the indoor heat exchanger 41 to the outdoor heat exchanger 21 through the 1 st pipe 51, and flows from the outdoor heat exchanger 21 to the indoor heat exchanger 41 through the 2 nd pipe 52. Arrows in fig. 1 indicate the flow of the refrigerant during the cooling operation.

Fig. 2 is a refrigerant system diagram schematically showing the air conditioner 10 during the heating operation according to the present embodiment. As shown in fig. 2, during the heating operation, the refrigerant flows from the outdoor heat exchanger 21 to the indoor heat exchanger 41 through the 1 st pipe 51, and flows from the indoor heat exchanger 41 to the outdoor heat exchanger 21 through the 2 nd pipe 52. Arrows in fig. 2 indicate the flow of the refrigerant during the heating operation.

The outdoor heat exchanger 21 of the outdoor unit 11 absorbs heat from the refrigerant as an evaporator or radiates heat from the refrigerant as a condenser, depending on the direction in which the refrigerant flows. The outdoor air-sending fan 22 sends air toward the outdoor heat exchanger 21, and promotes heat exchange between the refrigerant and the air in the outdoor heat exchanger 21. In other words, the outdoor blower fan 22 generates an air flow that exchanges heat with the outdoor heat exchanger 21.

The compressor 23 has a suction port 23a and a discharge port 23 b. The compressor 23 sucks the refrigerant from the suction port 23a, and discharges the compressed refrigerant from the discharge port 23 b. Thereby, the compressor 23 compresses the refrigerant in the refrigeration cycle, and generates a cycle of the refrigerant.

The accumulator 24 is connected to a suction port 23a of the compressor 23. The accumulator 24 separates the gaseous refrigerant from the liquid refrigerant. Thereby, the compressor 23 can suck the gaseous refrigerant passing through the accumulator 24 from the suction port 23 a. The accumulator 24 is formed integrally with the compressor 23, and thus can serve as a suction port of the compressor 23.

The four-way valve 25 is connected to the outdoor heat exchanger 21, the indoor heat exchanger 41, the discharge port 23b of the compressor 23, and the accumulator 24 (the suction port 23a of the compressor 23). The four-way valve 25 switches the flow paths connected to the outdoor heat exchanger 21, the indoor heat exchanger 41, the discharge port 23b of the compressor 23, and the accumulator 24 during the air-heating operation and the air-cooling operation, and changes the direction in which the refrigerant flows.

As shown in fig. 1, during the cooling operation, the four-way valve 25 connects the outdoor heat exchanger 21 to the discharge port 23b of the compressor 23. Further, during the cooling operation, the four-way valve 25 connects the indoor heat exchanger 41 and the accumulator 24. Thereby, the refrigerant compressed by the compressor 23 flows into the outdoor heat exchanger 21, and the refrigerant evaporated by the indoor heat exchanger 41 flows into the accumulator 24.

As shown in fig. 2, during the heating operation, the four-way valve 25 connects the outdoor heat exchanger 21 and the accumulator 24. Further, during the heating operation, the four-way valve 25 connects the indoor heat exchanger 41 to the discharge port 23b of the compressor 23. Thereby, the refrigerant compressed by the compressor 23 flows into the indoor heat exchanger 41, and the refrigerant evaporated by the outdoor heat exchanger 21 flows into the accumulator 24.

The 1 st expansion valve 31 and the 2 nd expansion valve 32 are, for example, electromagnetic expansion valves. The 1 st expansion valve 31 and the 2 nd expansion valve 32 may be other expansion valves. The 1 st expansion valve 31 and the 2 nd expansion valve 32 adjust the amount of refrigerant passing therethrough by controlling the opening degree.

The indoor heat exchanger 41 of the indoor unit 12 absorbs heat as an evaporator or radiates heat as a condenser depending on the direction in which the refrigerant flows. The indoor air-sending fan 42 sends air toward the indoor heat exchanger 41, and promotes heat exchange between the indoor heat exchanger 41 and the air. In other words, the indoor blower fan 42 generates an air flow that exchanges heat with the indoor heat exchanger 41.

In the air conditioner 10 in which the respective elements are arranged as described above, the 1 st pipe 51 includes the 1 st area 51a, the 2 nd area 51b, the 3 rd area 51c, and the 4 th area 51 d. The 1 st area 51a is a part of the 1 st pipe 51 between the indoor heat exchanger 41 and the four-way valve 25. The 2 nd area 51b is a part of the 1 st pipe 51 between the four-way valve 25 and the accumulator 24. The 3 rd region 51c is a part of the 1 st pipe 51 between the discharge port 23b of the compressor 23 and the four-way valve 25. The 4 th area 51d is a part of the 1 st pipe 51 between the four-way valve 25 and the outdoor heat exchanger 21.

The 2 nd pipe 52 has a 5 th region 52a and a 6 th region 52 b. The 5 th area 52a is a part of the 2 nd pipe 52 between the outdoor heat exchanger 21 and the 1 st expansion valve 31. The 6 th area 52b is a part of the 2 nd pipe 52 between the 1 st expansion valve 31 and the indoor heat exchanger 41.

The 2 nd expansion valve 32 is provided in the 2 nd area 51b of the 1 st pipe 51. In other words, the 2 nd expansion valve 32 is provided in the 1 st pipe 51 between the four-way valve 25 and the suction port 23a of the compressor 23.

The switching valve 33 is, for example, a three-way valve. The switching valve 33 may be another switching valve such as a four-way valve that can change the direction of the refrigerant flow. The switching valve 33 is provided in the 2 nd region 51b of the 1 st pipe 51 between the 2 nd expansion valve 32 and the suction port 23a of the compressor 23.

The 3 rd pipe 53 is connected to the 2 nd area 51b of the 1 st pipe 51. The 1 st end 53a of the 3 rd pipe 53 is connected to the switching valve 33. That is, the switching valve 33 is provided at a connection portion between the 1 st end 53a of the 3 rd pipe 53 and the 1 st pipe 51. The 2 nd end 53b of the 3 rd pipe 53 is connected to the 1 st pipe 51 between the switching valve 33 and the suction port 23a of the compressor 23. The 1 st end 53a is an example of one end of the 3 rd pipe. The 2 nd end portion 53b is an example of the other end portion of the 3 rd pipe.

The switching valve 33 switches the flow paths connected to the four-way valve 25, the suction port 23a of the compressor 23, and the 3 rd pipe 53, respectively, and changes the direction in which the refrigerant flows. That is, the switching valve 33 can cause the refrigerant flowing from the four-way valve 25 toward the suction port 23a of the compressor 23 to flow toward the suction port 23a of the compressor 23 via the 3 rd pipe 53.

The 1 st check valve 34 is provided in the 1 st pipe 51 between the switching valve 33 and the 2 nd end 53b of the 3 rd pipe 53. The 1 st check valve 34 allows the refrigerant flowing from the switching valve 33 toward the suction port 23a of the compressor 23 to pass therethrough. On the other hand, the 1 st check valve 34 blocks the refrigerant flowing in the direction from the suction port 23a of the compressor 23 to the switching valve 33.

The 2 nd check valve 35 is provided in the 3 rd pipe 53 between the switching valve 33 and the 2 nd end 53b of the 3 rd pipe 53. The 2 nd check valve 35 passes the refrigerant flowing from the switching valve 33 toward the suction port 23a of the compressor 23. On the other hand, the 2 nd check valve 35 blocks the refrigerant flowing from the suction port 23a of the compressor 23 toward the switching valve 33.

The outdoor unit 11 of the present embodiment further includes a 1 st heat storage material 61, a 2 nd heat storage material 62, a 3 rd heat storage material 63, a 1 st temperature sensor 71, a 2 nd temperature sensor 72, a 3 rd temperature sensor 73, a 4 th temperature sensor 74, a 5 th temperature sensor 75, a 6 th temperature sensor 76, and a 7 th temperature sensor 77. The 1 st heat storage material 61 is an example of a heat storage material. The 2 nd heat storage material 62 is an example of the 1 st heat transfer portion. The 3 rd heat storage material 63 is an example of the 2 nd heat transfer portion. The 2 nd temperature sensor 72 is an example of an indoor unit temperature sensor. The 3 rd temperature sensor 73 is an example of a heat storage material temperature sensor.

The 1 st, 2 nd, and 3 rd heat storage materials 61, 62, and 63 have latent heat storage materials filled in a block-shaped container, for example. The latent heat storage material is, for example, calcium chloride. The 1 st, 2 nd, and 3 rd heat storage materials 61, 62, and 63 may have other latent heat storage materials. The 1 st, 2 nd, and 3 rd heat storage materials 61, 62, and 63 in this embodiment are, for example, heat storage materials that can be used in a temperature band of about 10 ℃ to about 100 ℃.

The 1 st, 2 nd, and 3 rd heat storage materials 61, 62, and 63 are not limited to the above-described examples, and may be other heat storage materials such as sensible heat storage materials, or may be heat storage materials that can be used in other temperature bands. The 1 st, 2 nd, and 3 rd heat storage members 61, 62, and 63 may be different heat storage members from each other.

The 1 st heat storage material 61 is thermally connected to the 1 st region 51a of the 1 st pipe 51 between the indoor heat exchanger 41 and the four-way valve 25. Further, the 1 st heat storage material 61 is thermally connected to the 2 nd region 51b of the 1 st pipe 51 between the four-way valve 25 and the suction port 23a of the compressor 23. The 1 st heat storage material 61 may be thermally connected to only one of the 1 st region 51a and the 2 nd region 51 b.

For example, the 1 st region 51a and the 2 nd region 51b of the 1 st pipe 51 are separated from each other and penetrate the 1 st heat storage material 61. Therefore, the 1 st region 51a and the 2 nd region 51b are thermally connected to each other via the 1 st heat storage material 61.

In the present embodiment, the 1 st heat storage material 61 is thermally connected to the 2 nd region 51b of the 1 st pipe 51 between the four-way valve 25 and the 2 nd expansion valve 32. Therefore, the 2 nd expansion valve 32 is provided in the 1 st pipe 51 between the 1 st heat storage material 61 and the suction port 23a of the compressor 23.

The storable amount of heat (heat storage capacity) of the 1 st heat storage material 61 is larger than the storable amounts of heat in the 1 st region 51a and the 2 nd region 51b, respectively. The 1 st region 51a and the 2 nd region 51b are made of metal and are in close contact with the latent heat storage material of the 1 st heat storage material 61. Therefore, heat conduction is easily generated between the 1 st region 51a and the 2 nd region 51b and the latent heat storage material of the 1 st heat storage material 61.

The 2 nd heat storage material 62 is thermally connected to the 2 nd region 51b of the 1 st pipe 51 between the 2 nd expansion valve 32 and the suction port 23a of the compressor 23. In the present embodiment, the 2 nd heat storage material 62 is thermally connected to the 1 st pipe 51 between the switching valve 33 and the 1 st check valve 34. Therefore, the 1 st end 53a of the 3 rd pipe 53 is connected to the 1 st pipe 51 between the 2 nd expansion valve 32 and the 2 nd heat storage member 62. Further, the 2 nd end 53b of the 3 rd pipe 53 is connected to the 1 st pipe 51 between the 2 nd heat storage material 62 and the suction port 23a of the compressor 23.

Further, the 2 nd heat storage material 62 is thermally connected to the 5 th region 52a of the 2 nd pipe 52 between the outdoor heat exchanger 21 and the 1 st expansion valve 31. For example, the 1 st pipe 51 and the 2 nd pipe 52 are separated from each other and pass through the 2 nd heat storage material 62. Therefore, the 2 nd heat storage material 62 thermally connects the 1 st pipe 51 and the 2 nd pipe 52 to each other.

The heat storage capacity of the 2 nd heat storage member 62 is larger than the heat storage capacities of the 2 nd region 51b and the 5 th region 52a, respectively. The 2 nd region 51b and the 5 th region 52a are made of metal and are in close contact with the latent heat storage material of the 2 nd heat storage material 62. Therefore, heat conduction is easily generated between the 2 nd regions 51b and 5 th regions 52a and the latent heat storage material of the 2 nd heat storage material 62.

The 3 rd heat storage material 63 is thermally connected to the 3 rd pipe 53. In the present embodiment, the 3 rd heat storage material 63 is thermally connected to the 3 rd pipe 53 between the switching valve 33 and the 2 nd check valve 35.

Further, the 3 rd heat storage material 63 is thermally connected to the 6 th area 52b of the 2 nd pipe 52 between the indoor heat exchanger 41 and the 1 st expansion valve 31. For example, the 6 th region 52b and the 3 rd pipe 53 are separated from each other and penetrate the 3 rd heat storage member 63. Therefore, the 3 rd heat storage material 63 thermally connects the 6 th region 52b and the 3 rd pipe 53 to each other.

The heat storage capacity of the 3 rd heat storage material 63 is larger than the heat storage capacities of the 3 rd pipe 53 and the 6 th region 52b, respectively. The 3 rd pipe 53 and the 6 th region 52b are made of metal and are in close contact with the latent heat storage material of the 3 rd heat storage material 63. Therefore, heat conduction is easily generated between the 3 rd pipe 53 and the 6 th region 52b and the latent heat storage material of the 3 rd heat storage material 63.

The 1 st heat storage material 61 has a larger volume and a larger heat storage capacity than the 2 nd heat storage material 62 and the 3 rd heat storage material 63, respectively. The volume and the heat storage capacity of the latent heat storage materials of the 2 nd heat storage material 62 and the 3 rd heat storage material 63 are substantially the same. The volumes and heat storage capacities of the latent heat storage materials of the 2 nd heat storage material 62 and the 3 rd heat storage material 63 may be different from each other.

The 1 st temperature sensor 71 is disposed in, for example, a casing of the outdoor unit 11. The 1 st temperature sensor 71 detects the outside air temperature of the outdoor environment in which the outdoor unit 11 is disposed. The 2 nd temperature sensor 72 is provided in the indoor heat exchanger 41. The 2 nd temperature sensor 72 detects the temperature of the refrigerant flowing in the indoor heat exchanger 41. For example, the 2 nd temperature sensor 72 is disposed at a position where the saturation temperature of the refrigerant flowing through the indoor heat exchanger 41 can be acquired.

The 3 rd temperature sensor 73 is provided in the 1 st heat storage material 61. The 3 rd temperature sensor 73 detects the temperature of the 1 st heat storage material 61. The 4 th temperature sensor 74 is provided in the 2 nd region 51b of the 1 st pipe 51 in the vicinity of the accumulator 24. The 4 th temperature sensor 74 detects the temperature of the refrigerant flowing in the 2 nd area 51b in the vicinity of the accumulator 24.

The 5 th temperature sensor 75 is provided in the 2 nd region 51b of the 1 st pipe 51 between the 2 nd end 53b of the 3 rd pipe 53 and the tank 24 and in the vicinity of the 2 nd end 53 b. The 5 th temperature sensor 75 detects the temperature of the refrigerant flowing through the 2 nd area 51b in the vicinity of the 2 nd end 53 b.

The 6 th temperature sensor 76 is provided in the 6 th area 52b of the 2 nd pipe 52 between the indoor heat exchanger 41 and the 3 rd heat storage material 63 and in the vicinity of the 3 rd heat storage material 63. The 6 th temperature sensor 76 detects the temperature of the refrigerant flowing through the 6 th region 52b in the vicinity of the 3 rd heat storage material 63.

The control device 14 includes, for example, an outdoor control device 14a and an indoor control device 14 b. The outdoor control device 14a and the indoor control device 14b are electrically connected to each other by electric wiring. At least one of the outdoor control device 14a and the indoor control device 14b is, for example, a computer having a control device such as a cpu (central Processing unit) or a microcontroller, and a storage device such as a rom (read Only memory), a ram (random Access memory), or a flash memory. The control device 14 is not limited to this example. For example, the control device 14 may include only one of the outdoor control device 14a and the indoor control device 14 b.

The outdoor control device 14a controls the outdoor blower fan 22, the compressor 23, the four-way valve 25, the 1 st expansion valve 31, the 2 nd expansion valve 32, and the switching valve 33 of the outdoor unit 11. The indoor control device 14b controls the indoor blower fan 42 of the indoor unit 12.

The control device 14 controls the outdoor unit 11 and the indoor units 12, whereby the air conditioner 10 performs cooling operation, heating operation, dehumidifying operation, defrosting operation, cooling operation, and other operations. The indoor control device 14b may input a signal from, for example, a remote controller, or may input a signal from an information terminal such as a smartphone via a communication device.

Fig. 3 is a block diagram functionally showing the configuration of the air conditioner 10 according to the present embodiment. As shown in fig. 3, the air conditioner 10 of the present embodiment further includes an outdoor fan drive circuit 81, an indoor fan drive circuit 82, an inverter circuit 83, a four-way valve drive circuit 84, a 1 st expansion valve drive circuit 85, a 2 nd expansion valve drive circuit 86, and a switching valve drive circuit 87.

The outdoor fan drive circuit 81 is a drive circuit for the outdoor blower fan 22. The indoor fan drive circuit 82 is a drive circuit for the indoor blower fan 42. The inverter circuit 83 performs inverter control on the compressor 23 to change the operating frequency of the compressor 23. The frequency conversion circuit 83 is, for example, a frequency conversion circuit of a pam (pulse Amplitude modulation) system. The inverter circuit 83 is not limited to this example.

The four-way valve drive circuit 84 is a drive circuit of the four-way valve 25. The 1 st expansion valve driving circuit 85 is a driving circuit of the 1 st expansion valve 31. The 2 nd expansion valve drive circuit 86 is a drive circuit for the 2 nd expansion valve 32. The switching valve drive circuit 87 is a drive circuit of the switching valve 33.

The control device 14 is connected to the 1 st to 7 th temperature sensors 71 to 77, the outdoor fan drive circuit 81, the indoor fan drive circuit 82, the inverter circuit 83, the four-way valve drive circuit 84, the 1 st expansion valve drive circuit 85, the 2 nd expansion valve drive circuit 86, and the switching valve drive circuit 87. The control device 14 includes a temperature acquisition unit 91, an operation switching unit 92, an outdoor fan control unit 93, an indoor fan control unit 94, a compressor control unit 95, and a valve control unit 96.

The temperature acquisition unit 91 acquires the outside air temperature, the temperature of the refrigerant, and the temperature of the 1 st heat storage material 61 using the 1 st to 7 th temperature sensors 71 to 77. For example, the temperature acquisition unit 91 calculates the outside air temperature, the temperature of the refrigerant, and the temperature of the 1 st heat storage material 61 based on the output signals of the 1 st to 7 th temperature sensors 71 to 77.

The operation switching unit 92 switches the cooling operation, the heating operation, the dehumidifying operation, the defrosting operation, and the cooling operation in the air conditioner 10. The operation switching unit 92 may switch the operation of the air conditioner 10 to another operation method.

The outdoor fan controller 93 controls the outdoor blower fan 22. For example, the outdoor fan control unit 93 controls the outdoor fan drive circuit 81 to control the rotation speed of the motor of the outdoor blower fan 22.

The indoor fan control unit 94 controls the indoor blower fan 42. For example, the indoor fan control unit 94 controls the indoor fan drive circuit 82 to control the rotation speed of the motor of the indoor blower fan 42.

The compressor control unit 95 controls the compressor 23. For example, the compressor control unit 95 controls the inverter circuit 83 to control the operating frequency of the compressor 23 by inverter control.

The valve control unit 96 controls the four-way valve 25, the 1 st expansion valve 31, the 2 nd expansion valve 32, and the switching valve 33. The valve control unit 96 controls the four-way valve drive circuit 84 to drive the actuator of the four-way valve 25, thereby changing the direction of the refrigerant flow in the four-way valve 25. The valve control unit 96 controls the 1 st expansion valve drive circuit 85 and the 2 nd expansion valve drive circuit 86 to change the opening degrees of the 1 st expansion valve 31 and the 2 nd expansion valve 32. Further, the valve control unit 96 controls the switching valve drive circuit 87 to change the direction of the refrigerant flow in the switching valve 33.

The cooling operation, and the heating operation of the air conditioner 10 according to the present embodiment will be described below. As described above, the air conditioner 10 is not limited to the cooling operation, and the heating operation, and may perform other operations such as the dehumidifying operation and the defrosting operation. The cooling operation, and the heating operation of the air conditioner 10 are not limited to the examples described below.

Fig. 4 is a flowchart illustrating an example of the cooling operation control of the air conditioner 10 according to the present embodiment. For example, when the start of the air conditioner 10 and the start of the cooling operation are simultaneously performed, the outdoor air-sending fan 22, the compressor 23, and the indoor air-sending fan 42 are stopped. In this case, when the outdoor fan controller 93, the indoor fan controller 94, and the compressor controller 95 start the cooling operation, the outdoor air-sending fan 22, the compressor 23, and the indoor air-sending fan 42 are started.

During the cooling operation, the outdoor fan controller 93 adjusts the rotation speed of the outdoor blower fan 22. The indoor fan control unit 94 adjusts the rotation speed of the indoor air supply fan 42. The compressor control unit 95 adjusts the operating frequency of the compressor 23. For example, the indoor fan control unit 94 controls the indoor air supply fan 42 between a weak wind (low speed) operation and a strong wind (high speed) operation based on the indoor air temperature at which the indoor unit 12 is installed or a signal input from a remote controller.

As shown in fig. 4, when the cooling operation is started, the valve control unit 96 controls the four-way valve drive circuit 84 and the switching valve drive circuit 87 to change the direction of the refrigerant flow in the four-way valve 25 and the switching valve 33 (S101). Thereby, the outdoor heat exchanger 21 is connected to the discharge port 23b of the compressor 23, and the indoor heat exchanger 41 is connected to the accumulator 24 (the suction port 23a of the compressor 23). That is, the controller 14 performs a cooling operation in which the four-way valve 25 is controlled so that the refrigerant flows from the discharge port 23b of the compressor 23 to the outdoor heat exchanger 21. The 2 nd expansion valve 32 is connected to the suction port 23a of the compressor 23 via the 2 nd heat storage material 62.

Next, the operation switching unit 92 determines whether or not to end the cooling operation (S102). For example, when a stop signal or a switching signal to another operation is input from the remote controller to the air conditioner 10, the operation switching unit 92 determines that the cooling operation is ended (yes in S102), and ends the cooling operation.

If the cooling operation is not completed (no in S102), the valve control unit 96 determines whether or not the difference (superheat) between the temperature Ta and the temperature Tc is about 0 ℃ (S103). For example, the temperature acquiring unit 91 acquires the temperature Tc of the indoor heat exchanger 41 from the 2 nd temperature sensor 72. Further, the temperature acquisition unit 91 acquires the temperature Ta of the 1 st heat storage material 61 from the 3 rd temperature sensor 73.

The valve control unit 96 determines whether the degree of superheat (Ta-Tc) is about 0 ℃. For example, the valve control unit 96 determines whether or not the degree of superheat (Ta-Tc) is within the range of 0. + -. 0.5 ℃ in a predetermined time. The determination in S103 is not limited to this example.

When the degree of superheat (Ta-Tc) is not about 0 ℃ (S103: no), the valve control unit 96 controls the 1 st expansion valve drive circuit 85 to adjust the opening degree of the 1 st expansion valve 31 (S104). The valve control unit 96 adjusts the opening degree of the 1 st expansion valve 31 so that the degree of superheat (Ta-Tc) becomes about 0 ℃. In the case where the degree of superheat (Ta-Tc) in S103 is about 0 ℃ (S103: YES), S104 is omitted.

Then, the valve control unit 96 determines whether or not the difference (degree of superheat) between the temperature Su and the temperature Tk is 1 to 2 ℃ (S105). For example, the temperature acquisition unit 91 acquires the temperature Su of the refrigerant in the vicinity of the accumulator 24 from the 4 th temperature sensor 74. In other words, the temperature obtaining unit 91 obtains the temperature Su of the refrigerant entering the suction port 23a of the compressor 23 from the 4 th temperature sensor 74. Further, the temperature obtaining unit 91 obtains the temperature Tk of the refrigerant in the vicinity of the 2 nd end 53b of the 3 rd pipe 53 from the 5 th temperature sensor 75. In other words, the temperature acquisition unit 91 acquires the temperature Tk of the refrigerant coming out of the 2 nd heat storage material 62 from the 5 th temperature sensor 75.

The valve control unit 96 determines whether the degree of superheat (Su-Tk) is 1 to 2 ℃. For example, the valve control unit 96 determines whether or not the degree of superheat (Su-Tk) is within a range of 1 to 2 ℃ for a predetermined period of time. The determination in S105 is not limited to this example.

When the temperature difference (Su-Tk) is not 1 to 2 ℃ (NO in S105), the valve control unit 96 controls the 2 nd expansion valve drive circuit 86 to adjust the opening degree of the 2 nd expansion valve 32 (S106). The valve control unit 96 adjusts the opening degree of the 2 nd expansion valve 32 so that the degree of superheat (Su-Tk) is 1 to 2 ℃. When the degree of superheat (Su-Tk) in S105 is 1 to 2 ℃ (YES in S105), S106 is omitted.

When the valve control unit 96 adjusts the 2 nd expansion valve 32 or the degree of superheat (Su-Tk) to 1 to 2 ℃, the process returns to S102, and the operation switching unit 92 determines again whether or not the cooling operation is ended. S102 to S106 are repeated until the cooling operation is completed.

As shown in fig. 1, in the cooling operation, the high-temperature, high-pressure gas refrigerant discharged from the discharge port 23b of the compressor 23 radiates heat in the outdoor heat exchanger 21 through the four-way valve 25. The intermediate-temperature and intermediate-pressure liquid refrigerant condensed by the outdoor heat exchanger 21 is decompressed by the 1 st expansion valve 31.

The low-temperature low-pressure liquid refrigerant decompressed by the 1 st expansion valve 31 absorbs heat in the indoor heat exchanger 41. The gaseous refrigerant evaporated in the indoor heat exchanger 41 passes through the four-way valve 25 and is reduced in pressure by the 2 nd expansion valve 32. The refrigerant is returned to the suction port 23a of the compressor 23 through the switching valve 33 and the accumulator 24.

When the outdoor environment in which the outdoor unit 11 is disposed has a high outside air temperature, the refrigerant is less likely to condense in the outdoor heat exchanger 21. Therefore, the refrigerant flowing through the 5 th region 52a has a higher dryness, and the proportion of gas increases. If the ratio of the refrigerant in the gas state is high in the 5 th area 52a, the amount of the refrigerant that can pass through the 1 st expansion valve 31 decreases, and the capacity of the outdoor heat exchanger 21 may decrease.

For example, the cooling capacity (watt) of the air conditioner 10 when the outside air temperature is 48 ℃ may be reduced to about half of the cooling capacity (watt) of the air conditioner 10 when the outside air temperature is 35 ℃. The air conditioner 10 suppresses a decrease in the capacity of the indoor heat exchanger 41 due to an increase in the outside air temperature, and thus performs the following cooling operation.

Fig. 5 is a flowchart showing an example of the cooling operation control of the air conditioner 10 according to the present embodiment. The control device 14 of the present embodiment executes the cold storage operation at night when the air conditioner 10 is stopped, for example. The timing for executing the cooling operation is not limited to this example.

First, the operation switching unit 92 determines whether or not the start condition of the cooling operation is fulfilled (S201). For example, when the operation switching unit 92 determines that the air conditioner 10 is stopped and the time is 1 to 3 am (night), it determines that the start condition of the cold storage operation is fulfilled.

The starting conditions of the cooling operation are not limited to the above examples. For example, the operation switching unit 92 may determine the start condition of the cold storage operation based on the outside air temperature. In this case, the temperature acquisition unit 91 acquires the outside air temperature from the 1 st temperature sensor 71. The operation switching unit 92 determines that the start condition of the cold storage operation is fulfilled when the air conditioner is stopped and the outside air temperature is lower than the threshold value for a predetermined time.

The operation switching unit 92 may determine the start condition based on the presence of a person in the room. In this case, the operation switching unit 92 determines whether or not there is no person in the room based on an output signal of the human detection sensor provided in the indoor unit 12. When it is determined that no person is present in the room for a predetermined time, the operation switching unit 92 determines that the start condition of the cooling operation is fulfilled.

Further, the operation switching unit 92 may determine the start condition of the cooling operation based on the required capacity of the air conditioner 10. In this case, the operation switching unit 92 calculates the required capacity of the air conditioner 10 (the cooling capacity required for the air conditioner 10 to set the room temperature to the target temperature) based on the difference between the room temperature and the target temperature set by the user, and the like. The operation switching unit 92 determines that the start condition of the cooling operation is fulfilled when the required capacity of the air conditioner 10 is equal to or less than a predetermined threshold value.

When the start condition of the cooling operation is not satisfied (no in S201), the operation switching unit 92 waits without starting the cooling operation. When the start condition of the cooling operation is fulfilled (yes in S201), the outdoor fan controller 93, the indoor fan controller 94, and the compressor controller 95 start and adjust the outdoor air-sending fan 22, the compressor 23, and the indoor air-sending fan 42 (S202).

The valve control unit 96 changes the direction in which the refrigerant flows through the four-way valve 25 and the switching valve 33, as in the cooling operation. Thereby, the outdoor heat exchanger 21 is connected to the discharge port 23b of the compressor 23, and the indoor heat exchanger 41 is connected to the receiver 24 (the suction port 23a of the compressor 23). That is, the control device 14 performs the cooling operation in which the four-way valve 25 is controlled so that the refrigerant flows from the discharge port 23b of the compressor 23 to the outdoor heat exchanger 21. The 2 nd expansion valve 32 is connected to the suction port 23a of the compressor 23 via the 2 nd heat storage material 62.

The outdoor fan controller 93 and the compressor controller 95 control the outdoor blower fan 22 and the compressor 23 in the same manner as in the cooling operation. The control of the outdoor fan controller 93 and the compressor controller 95 during the cooling operation may be different from the control during the cooling operation.

On the other hand, the indoor fan control unit 94 controls the indoor blower fan 42 to be in a weak wind (low speed) operation. That is, the indoor fan control unit 94 rotates the indoor blower fan 42 at the lowest speed during the cooling operation. The control of the indoor fan control unit 94 is not limited to this example. For example, the indoor fan control unit 94 may stop the indoor blower fan 42.

Next, the operation switching unit 92 determines whether or not to end the cooling operation (S203). For example, when a stop signal or a switching signal to another operation is input from the remote controller to the air conditioner 10, the operation switching unit 92 determines that the cooling operation is ended (yes in S203), and ends the cooling operation.

When the cooling operation is not completed (no in S203), the operation switching unit 92 determines whether or not a predetermined time has elapsed from the start of the cooling operation (S204). For example, when 1 hour has elapsed since the start of the cooling operation (S204: YES), the operation switching unit 92 ends the cooling operation.

When a stop signal is input from the remote controller to the air conditioner 10 and when a predetermined time has elapsed from the start of the cooling operation, the outdoor fan controller 93, the indoor fan controller 94, and the compressor controller 95 stop the outdoor air-sending fan 22, the compressor 23, and the indoor air-sending fan 42.

When the predetermined time has not elapsed from the start of the cooling operation (no in S204), the valve control unit 96 determines whether or not the difference (degree of superheat) between the temperature Tc and the temperature Ta is about-2 ℃ (S205). For example, the temperature acquiring unit 91 acquires the temperature Tc of the indoor heat exchanger 41 from the 2 nd temperature sensor 72. Further, the temperature acquisition unit 91 acquires the temperature Ta of the 1 st heat storage material 61 from the 3 rd temperature sensor 73.

The valve control portion 96 determines whether the degree of superheat (Tc-Ta) is about-2 ℃. For example, the valve control unit 96 determines whether or not the degree of superheat (Tc-Ta) is within the range of-2. + -. 0.5 ℃ in a predetermined time. The determination in S205 is not limited to this example.

When the degree of superheat (Tc-Ta) is not about-2 ℃ (S205: No), the valve control unit 96 controls the 1 st expansion valve drive circuit 85 to adjust the opening degree of the 1 st expansion valve 31 (S206). The valve control unit 96 adjusts the opening degree of the 1 st expansion valve 31 so that the superheat degree (Tc-Ta) becomes about-2 ℃. For example, the valve control unit 96 sets the opening degree of the 1 st expansion valve 31 to be relatively large. In the case where the degree of superheat (Tc-Ta) in S205 is about-2 ℃ (S205: YES), S206 is omitted.

Then, the valve control unit 96 determines whether or not the difference (superheat) between the temperature Su and the temperature Tk is 1 to 2 ℃ (S207). For example, the temperature acquisition unit 91 acquires the temperature Su of the refrigerant in the vicinity of the accumulator 24 from the 4 th temperature sensor 74. Further, the temperature obtaining unit 91 obtains the temperature Tk of the refrigerant in the vicinity of the 2 nd end 53b of the 3 rd pipe 53 from the 5 th temperature sensor 75.

The valve control unit 96 determines whether the degree of superheat (Su-Tk) is 1 to 2 ℃. For example, the valve control unit 96 determines whether or not the degree of superheat (Su-Tk) is within a range of 1 to 2 ℃ for a predetermined period of time. The determination at S207 is not limited to this example.

When the degree of superheat (Su-Tk) is not 1 to 2 ℃ (NO in S207), the valve control unit 96 controls the 2 nd expansion valve drive circuit 86 to adjust the opening degree of the 2 nd expansion valve 32 (S208). The valve control unit 96 adjusts the opening degree of the 2 nd expansion valve 32 so that the degree of superheat (Su-Tk) is 1 to 2 ℃. When the degree of superheat (Su-Tk) in S207 is 1 to 2 ℃ (S207: YES), S208 is omitted.

If the valve control unit 96 adjusts the 2 nd expansion valve 32 or the degree of superheat (Su-Tk) to 1 to 2 ℃, the process returns to S203, and the operation switching unit 92 determines again whether or not to end the cold storage operation. S203 to S208 are repeated until the cooling operation is completed.

As shown in fig. 1, in the cooling operation, the high-temperature, high-pressure gas refrigerant discharged from the discharge port 23b of the compressor 23 is passed through the four-way valve 25 to be radiated by the outdoor heat exchanger 21. The intermediate-temperature and intermediate-pressure liquid refrigerant condensed by the outdoor heat exchanger 21 exchanges heat with the 2 nd heat storage material 62, and is decompressed by the 1 st expansion valve 31. The low-temperature low-pressure liquid refrigerant decompressed by the 1 st expansion valve 31 flows from the 1 st expansion valve 31 to the indoor heat exchanger 41.

In the cold storage operation, the valve control unit 96 controls the 1 st expansion valve 31 so that the refrigerant discharged from the indoor heat exchanger 41 contains more liquid than gas. Further, during the cooling operation, the indoor fan control unit 94 controls the indoor air-sending fan 42 so that the refrigerant discharged from the indoor heat exchanger 41 contains more liquid than the gas.

For example, as described above, the 1 st expansion valve 31 is adjusted in opening degree so that the degree of superheat (Tc-Ta) becomes about-2 ℃. Thereby, the refrigerant passes through the indoor heat exchanger 41 while remaining in a liquid state. Further, as described above, the indoor blower fan 42 performs the weak wind operation. Therefore, the refrigerant is difficult to exchange heat in the indoor heat exchanger 41, and the refrigerant passes through the indoor heat exchanger 41 while remaining in a liquid state. Further, the indoor air-sending fan 42 is operated with weak wind, thereby suppressing the occurrence of dew condensation in the indoor heat exchanger 41.

The low-temperature low-pressure liquid refrigerant that has flowed out of the indoor heat exchanger 41 exchanges heat with the 1 st heat storage material 61, and cools the 1 st heat storage material 61. The low-temperature, low-pressure refrigerant cools the 1 st heat storage material 61 twice when passing through the 1 st region 51a and when passing through the 2 nd region 51b of the 1 st pipe 51.

The liquid refrigerant discharged from the 1 st heat storage material 61 is decompressed by the 2 nd expansion valve 32. The liquid refrigerant decompressed by the 2 nd expansion valve 32 exchanges heat with the 2 nd heat storage material 62. In other words, the low-temperature low-pressure liquid refrigerant flowing through the 2 nd region 51b of the 1 st pipe 51 exchanges heat with the medium-temperature medium-pressure liquid refrigerant flowing through the 5 th region 52a of the 2 nd pipe 52 via the 2 nd heat storage material 62.

The liquid refrigerant flowing through the 2 nd region 51b is heated and vaporized by the medium-temperature and medium-pressure refrigerant flowing through the 5 th region 52a by the 2 nd heat storage material 62. The refrigerant vaporized by the 2 nd heat storage material 62 returns to the suction port 23a of the compressor 23 through the accumulator 24. The refrigerant is vaporized by the 2 nd heat storage material 62, and therefore, can be prevented from entering the suction port 23a of the compressor 23 while remaining in a liquid state.

During the cold storage operation, the valve control unit 96 controls the 2 nd expansion valve 32 to vaporize the refrigerant that has transferred to the 2 nd region 51b of the 2 nd heat storage material 62. For example, as described above, the opening degree of the 2 nd expansion valve 32 is adjusted so that the degree of superheat (Su-Tk) is 1 to 2 ℃. Thereby, the refrigerant is vaporized by heat transfer with the 2 nd heat storage material 62. In other words, the 2 nd expansion valve 32 adjusts the amount of the refrigerant supplied to the 2 nd heat storage material 62, thereby adjusting the degree of superheat of the refrigerant returning to the suction port 23a of the compressor 23.

On the other hand, the refrigerant flowing through the 5 th region 52a is cooled by the low-temperature and low-pressure refrigerant flowing through the 2 nd region 51 b. In the 5 th region 52a, the gaseous refrigerant that has not evaporated in the outdoor heat exchanger 21 may flow. In this case, the gaseous refrigerant is cooled and liquefied by the 2 nd heat storage material 62.

If the ratio of the refrigerant in the gas state is large in the 5 th area 52a, the amount of the refrigerant that can pass through the 1 st expansion valve 31 may decrease. In the present embodiment, the 2 nd heat storage material 62 liquefies the refrigerant, thereby increasing the proportion of the liquid in the refrigerant that passes through the 1 st expansion valve 31. Thereby, the 2 nd heat storage material 62 suppresses a decrease in the amount of the refrigerant supplied to the indoor heat exchanger 41.

As described above, the cold storage operation was performed for 1 hour. For example, even in summer, the outside air temperature is lower at night than during day. Therefore, the 1 st heat storage material 61 is sufficiently cooled during the night when the cold storage operation is performed.

In the cooling operation after the cold storage operation, the 1 st heat storage material 61 cools the refrigerant that has come out of the indoor heat exchanger 41. The refrigerant cooled by the 1 st heat storage material 61 is decompressed by the 2 nd expansion valve 32, and exchanges heat with the 2 nd heat storage material 62. In other words, the refrigerant flowing through the 2 nd area 51b of the 1 st pipe 51 exchanges heat with the intermediate-temperature, intermediate-pressure, liquid-state refrigerant flowing through the 5 th area 52a of the 2 nd pipe 52 via the 2 nd heat storage material 62.

The refrigerant flowing through the 2 nd area 51b is heated and vaporized by the medium-temperature and medium-pressure refrigerant flowing through the 5 th area 52 a. The refrigerant vaporized by the 2 nd heat storage material 62 returns to the suction port 23a of the compressor 23 through the accumulator 24. The refrigerant is vaporized by the 2 nd heat storage material 62, and therefore, can be prevented from entering the suction port 23a of the compressor 23 while remaining in a liquid state.

On the other hand, the refrigerant flowing in the 5 th region 52a is cooled by the refrigerant flowing in the 2 nd region 51 b. When the outside air temperature is high, the refrigerant is hard to condense in the outdoor heat exchanger 21. Therefore, the refrigerant flowing through the 5 th region 52a has a higher dryness, and the proportion of gas increases. However, the gaseous refrigerant is cooled and liquefied by the 2 nd heat storage material 62. The refrigerant is cooled by the 2 nd heat storage material 62, and thus the degree of supercooling of the refrigerant is, for example, 5 ℃. Thus, the 2 nd heat storage material 62 causes the liquid refrigerant to pass through the 1 st expansion valve 31, and suppresses a decrease in the amount of refrigerant supplied to the indoor heat exchanger 41.

As described above, the 2 nd heat storage material 62 turns the refrigerant supplied to the indoor heat exchanger 41 into a low-temperature low-pressure liquid state, and supplies a sufficient amount of refrigerant to the indoor heat exchanger 41. This makes it possible to suppress a decrease in the capacity of the indoor heat exchanger 41 in the air conditioner 10 even when the outside air temperature is high. Further, the 1 st heat storage material 61 cools the refrigerant in the 2 nd region 51b, whereby the 2 nd heat storage material 62 can cool the refrigerant in the 5 th region 52 a.

Fig. 6 is a flowchart illustrating an example of the heating operation control of the air conditioner 10 according to the present embodiment. For example, when the start of the air conditioner 10 and the start of the heating operation are simultaneously performed, the outdoor air-sending fan 22, the compressor 23, and the indoor air-sending fan 42 are stopped. In this case, when the outdoor fan controller 93, the indoor fan controller 94, and the compressor controller 95 start the heating operation, the outdoor air-sending fan 22, the compressor 23, and the indoor air-sending fan 42 are started.

As shown in fig. 6, when the heating operation is started, the valve control unit 96 controls the four-way valve drive circuit 84 and the switching valve drive circuit 87 to change the direction of the refrigerant flow in the four-way valve 25 and the switching valve 33 (S301). Thereby, the indoor heat exchanger 41 is connected to the discharge port 23b of the compressor 23, and the outdoor heat exchanger 21 is connected to the receiver 24 (the suction port 23a of the compressor 23). That is, the control device 14 performs a cooling operation in which the four-way valve 25 is controlled so that the refrigerant flows from the discharge port 23b of the compressor 23 to the indoor heat exchanger 41. The 2 nd expansion valve 32 is connected to the suction port 23a of the compressor 23 via a 3 rd pipe 53 and a 3 rd heat storage member 63.

Next, the operation switching unit 92 determines whether or not to end the heating operation (S302). For example, when a stop signal or a switching signal to another operation is input from the remote controller to the air conditioner 10, the operation switching unit 92 determines that the heating operation is ended (yes in S302), and ends the heating operation.

If the heating operation is not completed (no in S302), the valve control unit 96 determines whether or not the difference between the temperature Tc1 and the temperature Tc (the degree of supercooling) is about 3 ℃ (S303). For example, the temperature acquiring unit 91 acquires the temperature Tc of the indoor heat exchanger 41 from the 2 nd temperature sensor 72. Further, the temperature acquisition unit 91 acquires the temperature Tc1 of the refrigerant in the vicinity of the 3 rd heat storage material 63 from the 6 th temperature sensor 76.

The valve control unit 96 determines whether the supercooling degree (Tc1-Tc) is about 3 ℃. For example, the valve control unit 96 determines whether or not the supercooling degree (Tc1-Tc) is within the range of 3 ± 0.5 ℃ for a predetermined time. The determination at S303 is not limited to this example.

When the supercooling degree (Tc1-Tc) is not about 3 ℃ (S303: no), the valve control unit 96 controls the 1 st expansion valve driving circuit 85 to adjust the opening degree of the 1 st expansion valve 31 (S304). For example, the valve control unit 96 sets the opening degree of the 1 st expansion valve 31 to be relatively large. The valve control unit 96 adjusts the opening degree of the 1 st expansion valve 31 so that the supercooling degree (Tc1-Tc) becomes about 3 ℃. When the degree of supercooling (Tc1-Tc) is about 3 ℃ (S303: YES), S304 is omitted.

Next, the valve control portion 96 determines whether or not the difference (supercooling degree) between the temperature Su and the temperature Tk is about 5 ℃ (S305). For example, the temperature acquisition unit 91 acquires the temperature Su of the refrigerant in the vicinity of the accumulator 24 from the 4 th temperature sensor 74. Further, the temperature obtaining unit 91 obtains the temperature Tk of the refrigerant in the vicinity of the 2 nd end 53b of the 3 rd pipe 53 from the 5 th temperature sensor 75. In other words, the temperature acquisition unit 91 acquires the temperature Tk of the refrigerant coming out of the 3 rd heat storage material 63 from the 5 th temperature sensor 75.

The valve control portion 96 determines whether the degree of subcooling (Su-Tk) is about 5 ℃. For example, the valve control unit 96 determines whether or not the supercooling degree (Su-Tk) is within the range of 5 ± 0.5 ℃ for a predetermined time. The determination at S305 is not limited to this example.

When the degree of subcooling (Su-Tk) is not about 5 ℃ (S305: no), the valve control unit 96 controls the 2 nd expansion valve drive circuit 86 to adjust the opening degree of the 2 nd expansion valve 32 (S306). The valve control unit 96 adjusts the opening degree of the 2 nd expansion valve 32 so that the supercooling degree (Su-Tk) becomes about 5 ℃. When the degree of supercooling (Su-Tk) is about 5 ℃ in S305 (S305: YES), S306 is omitted.

Next, the valve control portion 96 determines whether or not the difference between the temperature Te and the outside air temperature To is about 2 ℃ (S307). For example, the temperature obtaining unit 91 obtains the outside air temperature To from the 1 st temperature sensor 71. Further, the temperature acquisition unit 91 acquires the temperature Te of the outdoor heat exchanger 21 from the 7 th temperature sensor 77.

The valve control unit 96 determines whether or not the temperature difference (Te-To) is about 2 ℃. For example, the valve control unit 96 determines whether or not the temperature difference (Te-To) is within the range of 2. + -. 0.5 ℃ within a predetermined time. The determination at S307 is not limited to this example.

When the temperature difference (Te-To) is not about 2 ℃ (S307: no), the valve control unit 96 controls the 1 st expansion valve drive circuit 85 To adjust the opening degree of the 1 st expansion valve 31 (S308). The valve control unit 96 adjusts the opening degree of the 1 st expansion valve 31 so that the temperature difference (Te-To) becomes about 2 ℃. In the case where the temperature difference (Te-To) is about 2 ℃ in S307 (S307: YES), S308 is omitted. The air conditioner 10 of the present embodiment can suppress the frost formation on the surface of the outdoor heat exchanger 21 by reducing the temperature difference (Te-To) To about 2 ℃.

Next, the valve control unit 96 determines whether or not the difference (degree of superheat) between the temperature Te and the temperature Su is 0 ℃ or less (S309). For example, the temperature acquisition unit 91 acquires the temperature Su of the refrigerant in the vicinity of the accumulator 24 from the 4 th temperature sensor 74. Further, the temperature acquisition unit 91 acquires the temperature Te of the outdoor heat exchanger 21 from the 7 th temperature sensor 77.

The valve control unit 96 determines whether or not the degree of superheat (Te-Su) is 0 ℃. For example, the valve control unit 96 determines whether or not the degree of superheat (Te-Su) is 0 ℃ or lower within a predetermined time. The determination at S308 is not limited to this example.

When the degree of superheat (Te-Su) is 0 ℃ or less (S309: YES), the valve control unit 96 controls the 2 nd expansion valve drive circuit 86 to adjust the opening degree of the 2 nd expansion valve 32 (S310). The valve control unit 96 adjusts the opening degree of the 2 nd expansion valve 32 so that the degree of superheat (Te-Su) becomes higher than 0 ℃. When the degree of superheat (Te-Su) is higher than 0 ℃ in S309 (S309: NO), S310 is omitted.

If the valve control unit 96 adjusts the 2 nd expansion valve 32 or the degree of superheat (Te-Su) is higher than 0 ℃, the process returns to S302, and the operation switching unit 92 determines again whether or not the heating operation is ended. S302 to S310 are repeated until the heating operation is completed.

As shown in fig. 2, during the heating operation, the gaseous refrigerant evaporated in the outdoor heat exchanger 21 exchanges heat with the 1 st heat storage material 61 through the four-way valve 25. In other words, the refrigerant flowing through the 2 nd area 51b of the 1 st pipe 51 exchanges heat with the high-temperature and high-pressure refrigerant flowing through the 1 st area 51a of the 1 st pipe 51 after coming out of the discharge port 23b of the compressor 23 via the 1 st heat storage material 61. Thereby, the refrigerant flowing through the 2 nd region 51b is heated by the refrigerant flowing through the 1 st region 51 a.

The refrigerant heated by the 1 st heat storage material 61 is decompressed by the 2 nd expansion valve 32. The refrigerant decompressed by the 2 nd expansion valve 32 exchanges heat with the 3 rd heat storage material 63 through the switching valve 33. The refrigerant then returns to the suction port 23a of the compressor 23 through the accumulator 24.

The high-temperature high-pressure gaseous refrigerant discharged from the discharge port 23b of the compressor 23 exchanges heat with the 1 st heat storage material 61 through the four-way valve 25. The refrigerant that has come out of the 1 st heat storage material 61 radiates heat in the indoor heat exchanger 41. In the heating operation of the present embodiment, the valve control unit 96 controls the 1 st expansion valve 31 so that the refrigerant discharged from the indoor heat exchanger 41 contains more gas than liquid. For example, as described above, the opening degree of the 1 st expansion valve 31 is adjusted so that the supercooling degree (Tc1-Tc) becomes about 3 ℃. Thereby, the refrigerant passes through the indoor heat exchanger 41 while remaining in a gaseous state.

The gas refrigerant has a higher heat exchange efficiency in the indoor heat exchanger 41 than the liquid refrigerant. Therefore, the 1 st expansion valve 31 keeps the refrigerant passing through the indoor heat exchanger 41 in a gaseous state, thereby improving the efficiency of heat exchange in the indoor heat exchanger 41.

The intermediate-temperature and intermediate-pressure gas refrigerant having passed through the indoor heat exchanger 41 exchanges heat with the 3 rd heat storage material 63. In other words, the medium-temperature and medium-pressure gas refrigerant flowing through the 6 th region 52b of the 2 nd pipe 52 and the low-temperature and low-pressure refrigerant flowing through the 3 rd pipe 53 exchange heat via the 3 rd heat storage material 63.

The gaseous refrigerant flowing through the 6 th region 52b is cooled and liquefied by the low-temperature low-pressure refrigerant flowing through the 3 rd pipe 53. That is, the 3 rd heat storage material 63 supplements the degree of subcooling of the refrigerant flowing in the 6 th region 52 b. The refrigerant liquefied by the 3 rd heat storage material 63 is decompressed by the 1 st expansion valve 31. Since the refrigerant is liquefied by the 3 rd heat storage material 63, the refrigerant can be prevented from entering the 1 st expansion valve 31 while remaining in a gaseous state.

The low-temperature low-pressure liquid refrigerant decompressed by the 1 st expansion valve 31 absorbs heat in the outdoor heat exchanger 21. As described above, the gaseous refrigerant evaporated by the outdoor heat exchanger 21 flows toward the suction port 23a of the compressor 23.

The refrigerant flowing through the 2 nd region 51b of the 1 st pipe 51 is heated by the refrigerant flowing through the 1 st region 51a via the 1 st heat storage material, and is heated by the refrigerant flowing through the 6 th region 52b via the 3 rd heat storage material. That is, the 1 st heat storage material 61 and the 3 rd heat storage material 63 supplement the degree of superheat of the refrigerant flowing in the 2 nd region 51 b.

As described above, the 1 st expansion valve 31 keeps the refrigerant of the indoor heat exchanger 41 in a gas state with high heat exchange efficiency. Further, the 3 rd heat storage material 63 liquefies the gaseous refrigerant that has come out of the indoor heat exchanger 41, and supplies the liquefied refrigerant to the 1 st expansion valve 31. This enables the air conditioner 10 to improve the capacity of the indoor heat exchanger 41.

When the outdoor air temperature of the environment outside the room where the outdoor unit 11 is disposed is low, the power consumption of the air conditioner 10 may increase. For example, the power consumption (watt) of the air conditioner 10 when the outside air temperature is 2 ℃ may be increased to 3 times or more the power consumption (watt) of the air conditioner 10 when the outside air temperature is 7 ℃. However, the air conditioner 10 according to the present embodiment can improve the efficiency of heat exchange in the indoor heat exchanger 41. Further, the 3 rd heat storage material 63 increases the temperature and pressure of the refrigerant returning to the compressor 23, thereby suppressing an increase in the amount of work of the compressor 23. Thus, the air conditioner 10 of the present embodiment can suppress an increase in power consumption of the air conditioner 10 due to a decrease in the outside air temperature, and can achieve energy saving.

Fig. 7 is a block diagram showing an example of the hardware configuration of the control device 14 according to the present embodiment. The control device 14 is realized by a computer 100 configured by hardware shown in fig. 7, for example.

The computer 100 has, for example, a CPU101, a ROM102, a RAM103, a storage device 104, and an interface (I/F) 106. The CPU101, ROM102, RAM103, storage 104, and I/F106 are connected by a bus.

The CPU101 can execute programs stored in the storage device 104 by being developed in the RAM103, control the respective units to perform input/output operations, and process data. The ROM102 stores a boot program for reading out a boot program of an operating system from the storage device 104 to the RAM 103.

The storage device 104 is, for example, a flash memory. The storage device 104 stores an operating system, application programs, and data. These programs are distributed as files in an installable or executable format stored in a computer-readable storage medium. Further, the program may be distributed by being downloaded from a server.

The I/F106 is an interface device for connecting to, for example, the 1 st to 7 th temperature sensors 71 to 77, the outdoor fan drive circuit 81, the indoor fan drive circuit 82, the inverter circuit 83, the four-way valve drive circuit 84, the 1 st expansion valve drive circuit 85, the 2 nd expansion valve drive circuit 86, and the switching valve drive circuit 87.

The program executed by the computer 100 according to the present embodiment may be provided as a computer-readable storage medium in which a file in an installable or executable format is stored in a CD-ROM, a Floppy Disk (FD), a CD-R, DVD, or the like.

The program executed by the computer 100 according to the present embodiment may be stored on a computer connected to a network such as the internet and may be provided by downloading the program via the network. The program executed by the computer 100 of the present embodiment may be provided or distributed via a network such as the internet. The program of the present embodiment may be provided by being embedded in the ROM102 or the like.

The program for causing the computer 100 to function as the control device 14 has a module configuration including a temperature acquisition module, an operation switching module, an outdoor fan control module, an indoor fan control module, a compressor control module, and a valve control module. The computer 100 reads out and executes a program from a storage medium (a storage device 104 or the like) by a processor (CPU101) which is actual hardware, and loads each module onto a main storage device (RAM 103). Thus, the processor (CPU101) functions as the temperature acquisition unit 91, the operation switching unit 92, the outdoor fan control unit 93, the indoor fan control unit 94, the compressor control unit 95, and the valve control unit 96 in fig. 3. The computer 100 may implement a part or all of the configuration of the temperature acquisition unit 91, the operation switching unit 92, the outdoor fan control unit 93, the indoor fan control unit 94, the compressor control unit 95, and the valve control unit 96 by hardware.

In the air conditioner 10 of the embodiment described above, the 1 st heat storage material 61 is thermally connected to the 1 st pipe 51 at least one of between the indoor heat exchanger 41 and the four-way valve 25 and between the four-way valve 25 and the suction port 23a of the compressor 23. The 2 nd expansion valve 32 is provided in the 1 st pipe 51 between the four-way valve 25 and the suction port 23a of the compressor 23 and between the 1 st heat storage material 61 and the suction port 23a of the compressor 23. The 2 nd heat storage material 62 is thermally connected to the 1 st pipe 51 between the 2 nd expansion valve 32 and the suction port 23a of the compressor 23, and is thermally connected to the 2 nd pipe 52 between the outdoor heat exchanger 21 and the 1 st expansion valve 31. Thus, for example, when the outside air temperature is lower than the predetermined temperature, the low-temperature refrigerant discharged from the indoor heat exchanger 41 cools the 1 st heat storage material 61 by the cooling operation or the cold storage operation in which the refrigerant is circulated in the same direction as the cooling operation. By cooling the 1 st heat storage material 61, the air conditioner 10 can keep the temperature of the refrigerant entering the indoor heat exchanger 41 at a desired low temperature even when the outside air temperature is higher than a predetermined temperature, for example. For example, the refrigerant that has exited the indoor heat exchanger 41 is cooled by the 1 st heat storage material 61, passes through the 2 nd expansion valve 32, and reaches the 2 nd heat storage material 62. The 2 nd heat storage material 62 exchanges heat between the low-temperature refrigerant in the 1 st pipe 51 and the refrigerant flowing out of the outdoor heat exchanger 21 located outdoors at a high temperature. The refrigerant that has exited the outdoor heat exchanger 21 is cooled and liquefied by the 2 nd heat storage material 62, and is decompressed by the 1 st expansion valve 31. Since the 2 nd heat storage material 62 liquefies the refrigerant, a sufficient amount of the refrigerant can pass through the 1 st expansion valve 31. Accordingly, a sufficient amount of low-temperature low-pressure liquid refrigerant enters the indoor heat exchanger 41 (evaporator), and therefore the air conditioner 10 can suppress a decrease in the capacity of the indoor heat exchanger 41 due to an increase in the outside air temperature, and can achieve energy saving. The refrigerant in the 1 st pipe 51 is heated and vaporized by the 2 nd heat storage material 62, and enters the suction port 23a of the compressor 23. This allows the air conditioner 10 to suppress the liquid refrigerant from entering the suction port 23a of the compressor 23.

The 1 st heat storage material 61 is thermally connected to the 1 st pipe 51 between the indoor heat exchanger 41 and the four-way valve 25, and is thermally connected to the 1 st pipe 51 between the four-way valve 25 and the suction port 23a of the compressor 23. Thus, for example, when the outside air temperature is lower than a predetermined temperature, the low-temperature refrigerant that has exited the indoor heat exchanger 41 can further cool the 1 st heat storage material 61 by the cooling operation or the cold storage operation.

The 1 st end 53a of the 3 rd pipe 53 is connected to the 1 st pipe 51 between the 2 nd expansion valve 32 and the 2 nd heat storage material 62. The 2 nd end 53b of the 3 rd pipe 53 is connected to the 1 st pipe 51 between the 2 nd heat storage material 62 and the suction port 23a of the compressor 23. The switching valve 33 is provided at a connection portion between the 1 st end 53a of the 3 rd pipe 53 and the 1 st pipe 51, and is capable of changing the direction of the refrigerant flow. The 3 rd heat storage material 63 is thermally connected to the 3 rd pipe 53, and is thermally connected to the 2 nd pipe 52 between the indoor heat exchanger 41 and the 1 st expansion valve 31. For example, the switching valve 33 causes the refrigerant to flow toward the 2 nd heat storage material 62 during the cooling operation, and causes the refrigerant to flow toward the 3 rd heat storage material 63 during the heating operation. During the heating operation, the refrigerant flowing out of the outdoor heat exchanger 21 passes through the 1 st heat storage material 61 and the 2 nd expansion valve 32, and reaches the 3 rd heat storage material 63. The 3 rd heat storage material 63 exchanges heat between the low-temperature refrigerant in the 3 rd pipe 53 and the refrigerant flowing out of the indoor heat exchanger 41. The refrigerant flowing out of the indoor heat exchanger 41 is cooled and liquefied by the 3 rd heat storage material 63, and is reduced in pressure by the 1 st expansion valve 31. Since the 3 rd heat storage material 63 liquefies the refrigerant, a sufficient amount of the refrigerant can pass through the 1 st expansion valve 31. Accordingly, a sufficient amount of liquid refrigerant enters the outdoor heat exchanger 21 (evaporator), and therefore, the air conditioner 10 can suppress a decrease in the capacity of the outdoor heat exchanger 21, and can achieve energy saving. Further, since the 3 rd heat storage material 63 liquefies the refrigerant, the air conditioner 10 can exchange heat in the indoor heat exchanger 41 without condensing the refrigerant. The efficiency of heat exchange of the gaseous refrigerant is high. Therefore, the air conditioner 10 can improve the capacity of the indoor heat exchanger 41 and can achieve energy saving. Further, since the efficiency of heat exchange in the indoor heat exchanger 41 is improved, the air conditioner 10 can reduce the work of the compressor 23, and can achieve energy saving. The 1 st heat storage material 61 exchanges heat between the high-temperature refrigerant flowing out of the discharge port 23b of the compressor 23 and the low-temperature refrigerant flowing out of the outdoor heat exchanger 21. Thus, the refrigerant that has exited the outdoor heat exchanger 21 is heated and sufficiently vaporized by the 1 st heat storage material 61 and the 3 rd heat storage material 63. Therefore, the air conditioner 10 can suppress the liquid refrigerant from entering the suction port 23a of the compressor 23.

In the cold storage operation, the controller 14 controls the 1 st expansion valve 31 and the indoor air blowing fan 42 so that the refrigerant discharged from the indoor heat exchanger 41 contains more liquid than the gas. Further, the controller 14 controls the 2 nd expansion valve 32 to vaporize the refrigerant that has transferred to the 2 nd heat storage material 62. Thus, the air conditioner 10 can further cool the 1 st heat storage material 61 by the low-temperature refrigerant as a liquid during the cold storage operation. Further, since the refrigerant is vaporized by the 2 nd heat storage material 62, the air conditioner 10 can suppress the liquid refrigerant from entering the suction port 23a of the compressor 23.

The control device 14 controls the opening degree of the 1 st expansion valve 31 based on the difference between the temperature Tc detected by the 2 nd temperature sensor 72 and the temperature Ta detected by the 3 rd temperature sensor 73 during the cold storage operation. Thus, the air conditioner 10 can make the refrigerant discharged from the indoor heat exchanger 41 contain more liquid than gas.

During the heating operation, the controller 14 controls the 1 st expansion valve 31 so that the refrigerant discharged from the indoor heat exchanger 41 contains more gas than liquid. The gas refrigerant has a higher heat exchange efficiency in the indoor heat exchanger 41 than the liquid refrigerant. This improves the capacity of the indoor heat exchanger 41, and therefore, energy saving of the air conditioner 10 can be achieved.

In the above embodiment, the 2 nd area 51b of the 1 st pipe 51 and the 5 th area 52a of the 2 nd pipe 52 exchange heat via the 2 nd heat storage material 62. Further, the 3 rd pipe 53 and the 6 th region 52b of the 2 nd pipe 52 exchange heat via the 3 rd heat storage member 63. However, a heat-transferable member (heat transfer portion) such as copper may be provided instead of the 2 nd heat storage material 62 and the 3 rd heat storage material 63. However, the 2 nd heat storage material 62 and the 3 rd heat storage material 63 can stabilize heat transfer as compared with a member such as copper.

In the above embodiment, the air conditioner 10 can perform the cooling operation, and the heating operation by changing the direction of the refrigerant flow by the four-way valve 25. However, the air conditioner 10 may not have the four-way valve 25 and may perform only the cooling operation and the cooling operation. In this case, the air conditioner 10 may omit the switching valve 33, the 3 rd pipe 53, and the 3 rd heat storage material 63.

Several embodiments of the present invention have been described, but these embodiments are presented as examples and are not intended to limit the scope of the invention. These new embodiments can be implemented in other various ways, and various omissions, substitutions, and changes can be made without departing from the spirit of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the inventions described in the claims and the equivalent scope thereof.

Claims (6)

1. An air conditioner is provided with:

an indoor heat exchanger;

an outdoor heat exchanger;

a 1 st pipe for connecting the indoor heat exchanger and the outdoor heat exchanger and allowing a refrigerant to flow therethrough;

a 2 nd pipe for connecting the outdoor heat exchanger and the indoor heat exchanger and allowing the refrigerant to flow therethrough;

a compressor provided in the 1 st pipe and having a suction port for sucking the refrigerant and a discharge port for discharging the refrigerant;

a four-way valve provided in the 1 st pipe and capable of changing a direction in which the refrigerant flows;

a 1 st expansion valve provided in the 2 nd pipe;

a heat storage member thermally connected to the 1 st pipe at least one of between the indoor heat exchanger and the four-way valve and between the four-way valve and the suction port of the compressor;

a 2 nd expansion valve provided in the 1 st pipe between the four-way valve and the suction port of the compressor and between the heat storage material and the suction port of the compressor; and

and a 1 st heat transfer unit thermally connected to the 1 st pipe between the 2 nd expansion valve and the suction port of the compressor, and thermally connected to the 2 nd pipe between the outdoor heat exchanger and the 1 st expansion valve.

2. The air conditioner according to claim 1,

the heat storage material is thermally connected to the 1 st pipe between the indoor heat exchanger and the four-way valve, and is thermally connected to the 1 st pipe between the four-way valve and the suction port of the compressor.

3. The air conditioner according to claim 1 or 2,

the air conditioner further includes:

a 3 rd pipe having one end connected to the 1 st pipe between the 2 nd expansion valve and the 1 st heat transfer portion and the other end connected to the 1 st pipe between the 1 st heat transfer portion and the suction port of the compressor;

a switching valve provided at a connection portion between the one end of the 3 rd pipe and the 1 st pipe, the switching valve being capable of changing a direction in which the refrigerant flows; and

and a 2 nd heat transfer portion thermally connected to the 3 rd pipe and thermally connected to the 2 nd pipe between the indoor heat exchanger and the 1 st expansion valve.

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

the air conditioner further includes:

an indoor air supply fan for generating air flow for heat exchange with the indoor heat exchanger; and

a control device for controlling the four-way valve, the 1 st expansion valve, the 2 nd expansion valve and the indoor air supply fan,

the control device can execute:

a cooling operation in which the four-way valve is controlled so that the refrigerant flows from the discharge port of the compressor to the outdoor heat exchanger; and

a cold storage operation in which the four-way valve is controlled so that the refrigerant flows from the discharge port of the compressor to the outdoor heat exchanger, the 1 st expansion valve and the indoor air-sending fan are controlled so that the refrigerant discharged from the indoor heat exchanger contains more liquid than gas, and the 2 nd expansion valve is controlled so that the refrigerant having transferred heat to the 1 st heat transfer portion is vaporized.

5. The air conditioner according to claim 4,

the air conditioner further includes:

an indoor unit temperature sensor that detects a temperature of the refrigerant flowing through the indoor heat exchanger; and

a heat storage material temperature sensor for detecting the temperature of the heat storage material,

the control device controls the opening degree of the 1 st expansion valve based on a difference between the temperature detected by the indoor unit temperature sensor and the temperature detected by the heat storage material temperature sensor during the cooling operation.

6. The air conditioner according to claim 3,

the air conditioner further comprises a control device for controlling the four-way valve, the 1 st expansion valve and the 2 nd expansion valve,

the controller may be configured to perform a heating operation in which the four-way valve is controlled so that the refrigerant flows from the discharge port of the compressor to the indoor heat exchanger, and the 1 st expansion valve is controlled so that the refrigerant discharged from the indoor heat exchanger contains more gas than liquid.

Images