Refrigeration cycle device

Abstract

In this refrigeration cycle device, a refrigerant circuit switching unit (15a...15e), when in a first operation mode, switches to a refrigerant circuit in which: a refrigerant that has flowed out from a heat dissipation unit (12) is allowed to be sucked into a second compression unit (112); the refrigerant that has been discharged from the second compression unit (112) is allowed to flow into a heat absorption / dissipation unit (16); the pressure of the refrigerant, the heat of which has been dissipated by the heat absorption / dissipation unit (16), is reduced by means of a second decompression unit (14b); and the refrigerant that has flowed out from a heat absorption unit (18) is allowed to be sucked into a first compression unit (111). In a second operation mode, the switching unit switches to a refrigerant circuit which: reduces the pressure of the refrigerant flowing out from the heat dissipation unit (12), by means of a first decompression unit (14a); causes the refrigerant flowing out from the first decompression unit (14a) to flow into the heat absorption / dissipation unit (16); and causes the refrigerant the heat of which has been absorbed by the heat absorption / dissipation unit (16) to be sucked into the first compression unit (111).

Description

Refrigeration Cycle Equipment CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application is based on Japanese Patent Application No. 2024-066794 filed on April 17, 2024, the contents of which are incorporated herein by reference.

[0002] The present disclosure relates to a refrigeration cycle device configured to be able to switch refrigerant circuits.

[0003] BACKGROUND ART Patent Document 1 discloses a two-stage compression refrigeration cycle device that is applied to a refrigeration system.

[0004] In the refrigeration cycle device of Patent Document 1, intermediate-pressure refrigerant heated in an intermediate heat exchanger and intermediate-pressure refrigerant cooled in an intercooler are mixed and drawn into a high-pressure compression mechanism. The intermediate heat exchanger is an intermediate-pressure internal heat exchanger that exchanges heat between the high-pressure refrigerant discharged from the high-pressure compression mechanism and the intermediate-pressure refrigerant decompressed by an intermediate-pressure expansion valve. The intercooler is an air-cooling heat exchanger that exchanges heat between the intermediate-pressure refrigerant discharged from the low-pressure compression mechanism and outside air.

[0005] Furthermore, in the refrigeration cycle device of Patent Document 1, the throttling opening of the intermediate-pressure expansion valve is appropriately adjusted to prevent the temperature of the high-pressure refrigerant discharged from the high-stage compression mechanism from exceeding the heat-resistant temperature of the high-stage compression mechanism.

[0006] JP 2013-155972 A

[0007] The refrigeration cycle device of Patent Document 1 is used solely to cool the air inside the showcase unit that is circulated and blown in. However, a refrigeration cycle device applied to an air conditioner or the like is required to not only cool the air blown into the room as an object to be cooled, but also heat the air as an object to be heated.

[0008] In response to this, it is conceivable to add a function of heating an object by making the refrigerant circuit of the refrigeration cycle device of Patent Document 1 switchable. However, in general, the cycle balance in an operation mode for cooling an object to be cooled differs from the cycle balance in an operation mode for heating an object to be heated.

[0009] Therefore, the pressure resistance and heat resistance of each component must be determined according to the cycle balance in an operation mode that requires high pressure resistance and heat resistance. As a result, in a refrigeration cycle device configured to be able to switch refrigerant circuits, the component devices tend to become larger and heavier, which can lead to a decrease in productivity of the refrigeration cycle device as a whole.

[0010] In view of the above, an object of the present disclosure is to provide a refrigeration cycle apparatus configured to be able to switch refrigerant circuits, which is less likely to result in a decrease in productivity.

[0011] A refrigeration cycle device according to a first aspect of the present disclosure includes a first compression section, a heat dissipation section, a first pressure reduction section, a second compression section, a heat absorption and dissipation section, a second pressure reduction section, a heat absorption section, and a refrigerant circuit switching section.

[0012] The first compression unit compresses and discharges the refrigerant. The heat dissipation unit dissipates heat from the refrigerant discharged from the first compression unit. The first pressure reduction unit depressurizes the refrigerant. The second compression unit compresses and discharges the refrigerant. The heat absorption and dissipation unit absorbs or dissipates heat from the refrigerant. The second pressure reduction unit depressurizes the refrigerant. The heat absorption unit causes the refrigerant depressurized by the second pressure reduction unit to absorb heat. The refrigerant circuit switching unit switches the refrigerant circuit that circulates the refrigerant.

[0013] In the first operation mode, the refrigerant circuit switching unit switches to a refrigerant circuit in which the refrigerant flowing out from the heat radiating unit is drawn into the second compressing unit, the refrigerant discharged from the second compressing unit is drawn into the heat absorbing and radiating unit, the refrigerant that has radiated heat in the heat absorbing and radiating unit is decompressed in the second decompressing unit, and the refrigerant flowing out from the heat absorbing unit is drawn into the first compressing unit.

[0014] In the second operating mode, the refrigerant circuit switching unit depressurizes the refrigerant flowing out from the heat dissipation unit in the first pressure reduction unit, causes the refrigerant flowing out from the first pressure reduction unit to flow into the heat absorption and dissipation unit, and switches to a refrigerant circuit in which the refrigerant that has absorbed heat in the heat absorption and dissipation unit is sucked into the first compression unit.

[0015] According to this, in the first operation mode, a vapor compression refrigeration cycle can be configured in which the refrigerant is compressed in two stages, in the first compression section and the second compression section, and in the second operation mode, a vapor compression refrigeration cycle can be configured in which the refrigerant is compressed in the first compression section. Therefore, an operation mode that provides a more appropriate cycle balance can be selected depending on the application.

[0016] Furthermore, in both operation modes, the heat dissipation unit is used as a heat exchanger for dissipating heat from the refrigerant. Therefore, even if the refrigerant circuit is configured to be switchable, it is possible to prevent the number of heat exchangers from increasing depending on the operation mode.

[0017] In addition, the heat absorption section is used as a heat exchanger to evaporate the refrigerant. Therefore, the pressure resistance and heat resistance of the heat absorption section can be made lower than those of the heat radiation section and the heat absorption / radiation section. This prevents the heat absorption section from becoming larger and heavier.

[0018] In the first operating mode, the refrigerant cooled in the heat dissipation section is drawn into the second compression section, which suppresses the temperature rise of the refrigerant discharged from the second compression section, thereby reducing the heat resistance of the second compression section and suppressing increases in size and weight of the second compression section.

[0019] As a result, according to the refrigeration cycle apparatus of the first aspect, even in a refrigeration cycle apparatus configured to be able to switch refrigerant circuits, it is possible to suppress a decrease in productivity.

[0020] In addition, a second aspect of the refrigeration cycle device includes a first compression section, a heat dissipation section, a first pressure reduction section, a second compression section, a heat absorption and dissipation section, a second pressure reduction section, a heat absorption section, and a refrigerant circuit switching section.

[0021] The first compression unit compresses and discharges the refrigerant. The heat dissipation unit dissipates heat from the refrigerant discharged from the first compression unit. The first pressure reduction unit depressurizes the refrigerant. The second compression unit compresses and discharges the refrigerant. The heat absorption and dissipation unit absorbs or dissipates heat from the refrigerant. The second pressure reduction unit depressurizes the refrigerant. The heat absorption unit causes the refrigerant depressurized by the second pressure reduction unit to absorb heat. The refrigerant circuit switching unit switches the refrigerant circuit that circulates the refrigerant.

[0022] In the first operation mode, the refrigerant circuit switching unit switches to a refrigerant circuit in which the refrigerant flowing out from the heat radiating unit is drawn into the second compressing unit, the refrigerant discharged from the second compressing unit is drawn into the heat absorbing and radiating unit, the refrigerant that has radiated heat in the heat absorbing and radiating unit is decompressed in the second decompressing unit, and the refrigerant flowing out from the heat absorbing unit is drawn into the first compressing unit.

[0023] In the third operating mode, the refrigerant circuit switching unit switches to a refrigerant circuit that causes the refrigerant flowing out of the heat dissipation unit to flow into the first pressure reduction unit, causes the refrigerant flowing out of the first pressure reduction unit to flow into the heat absorption and dissipation unit, reduces the pressure of the refrigerant that has dissipated heat in the heat absorption and dissipation unit in the second pressure reduction unit, and causes the refrigerant flowing out of the heat absorption unit to be sucked into the first compression unit.

[0024] According to this, as with the refrigeration cycle device of the first aspect, a two-stage compression vapor compression refrigeration cycle can be configured in the first operation mode, and a single-stage compression vapor compression refrigeration cycle can be configured in the third operation mode. Therefore, an operation mode that provides a more appropriate cycle balance can be selected depending on the application.

[0025] Furthermore, as in the refrigeration cycle apparatus of the first aspect, an increase in the number of heat exchangers can be suppressed, and as in the refrigeration cycle apparatus of the first aspect, an increase in the size and weight of the heat absorption section and the second compression section can be suppressed.

[0026] As a result, according to the refrigeration cycle apparatus of the second aspect, even in a refrigeration cycle apparatus configured to be able to switch refrigerant circuits, it is possible to suppress a decrease in productivity.

[0027] In addition, the refrigeration cycle device of the third aspect includes a first compression section, a heat dissipation section, a first pressure reduction section, a second compression section, a first heat absorption and radiation section, a second pressure reduction section, a second heat absorption and radiation section, and a refrigerant circuit switching section.

[0028] The first compression unit compresses and discharges the refrigerant. The heat dissipation unit dissipates heat from the refrigerant discharged from the first compression unit. The first pressure reduction unit depressurizes the refrigerant. The second compression unit compresses and discharges the refrigerant. The first heat absorption and radiation unit absorbs or dissipates heat from the refrigerant. The second pressure reduction unit depressurizes the refrigerant. The second heat absorption and radiation unit absorbs or dissipates heat from the refrigerant flowing out from the second pressure reduction unit. The refrigerant circuit switching unit switches the refrigerant circuit that circulates the refrigerant.

[0029] In the first operation mode, the refrigerant circuit switching unit switches to a refrigerant circuit that causes the refrigerant flowing out from the heat radiating unit to be drawn into the second compression unit, causes the refrigerant discharged from the second compression unit to flow into the first heat absorbing and radiating unit, reduces the pressure of the refrigerant that has radiated heat in the first heat absorbing and radiating unit in the second decompression unit, and draws the refrigerant that has absorbed heat in the second heat absorbing and radiating unit into the first compression unit.

[0030] In the fourth operating mode, the refrigerant circuit switching unit switches to a refrigerant circuit that causes the refrigerant flowing out from the heat dissipation unit to flow into the second pressure reduction unit, reduces the pressure of the refrigerant that has dissipated heat in the second heat absorption and dissipation unit in the first pressure reduction unit, causes the refrigerant flowing out from the first pressure reduction unit to flow into the first heat absorption and dissipation unit, and sucks the refrigerant that has absorbed heat in the first heat absorption and dissipation unit into the first compression unit.

[0031] According to this, as with the refrigeration cycle device of the first aspect, a two-stage compression vapor compression refrigeration cycle can be configured in the first operation mode, and a single-stage compression vapor compression refrigeration cycle can be configured in the fourth operation mode. Therefore, an operation mode that provides a more appropriate cycle balance can be selected depending on the application.

[0032] Furthermore, as in the refrigeration cycle apparatus of the first aspect, an increase in the number of heat exchangers can be suppressed, and as in the refrigeration cycle apparatus of the first aspect, an increase in the size and weight of the second compression section can be suppressed.

[0033] As a result, according to the refrigeration cycle apparatus of the third aspect, even in a refrigeration cycle apparatus configured to be able to switch refrigerant circuits, it is possible to suppress a decrease in productivity.

[0034] Furthermore, a fourth aspect of the refrigeration cycle device includes a first compression section, a first heat dissipation section, a second compression section, a second heat dissipation section, a second pressure reduction section, a first heat absorption section, a fourth pressure reduction section, a second heat absorption section, and a refrigerant circuit switching section.

[0035] The first compression unit compresses and discharges the refrigerant. The first heat dissipation unit dissipates heat from the refrigerant discharged from the first compression unit. The second compression unit compresses and discharges the refrigerant. The second heat dissipation unit dissipates heat from the refrigerant discharged from the second compression unit. The second pressure reduction unit depressurizes the refrigerant flowing out from the second heat dissipation unit. The first heat absorption unit causes the refrigerant depressurized by the second pressure reduction unit to absorb heat. The fourth pressure reduction unit depressurizes the refrigerant flowing out from the second heat dissipation unit. The second heat absorption unit causes the refrigerant depressurized by the fourth pressure reduction unit to absorb heat. The refrigerant circuit switching unit switches the refrigerant circuit that circulates the refrigerant. The heat absorption performance of the first heat absorption unit and the heat absorption performance of the second heat absorption unit are different from each other.

[0036] In the first operation mode, the refrigerant circuit switching unit switches to a refrigerant circuit in which the refrigerant flowing out of the first heat radiating unit is drawn into the second compressing unit, the refrigerant flowing out of the second heat radiating unit is drawn into the second decompressing unit, and the refrigerant flowing out of the first heat absorbing unit is drawn into the first compressing unit.

[0037] In the fifth operation mode, the refrigerant circuit switching unit switches to a refrigerant circuit in which the refrigerant flowing out of the first heat radiating unit is drawn into the second compressing unit, the refrigerant flowing out of the second heat radiating unit is drawn into the fourth decompressing unit, and the refrigerant flowing out of the second heat absorbing unit is drawn into the first compressing unit.

[0038] This allows the first heat absorption section and the second heat absorption section, which have different heat exchange capacities, to be selected as the heat exchange section for evaporating the refrigerant depending on the operation mode, and therefore allows the operation mode that provides a more appropriate cycle balance to be selected depending on the application.

[0039] Furthermore, in both operation modes, the first heat radiating portion and the second heat radiating portion are used as heat exchangers for radiating heat from the refrigerant, so that, similar to the refrigeration cycle apparatus of the first aspect, an increase in the number of heat exchangers can be suppressed.

[0040] Furthermore, similarly to the refrigeration cycle device of the first aspect, it is possible to suppress an increase in size and weight of the first heat absorption section, the second heat absorption section, and the second compression section.

[0041] As a result, according to the refrigeration cycle apparatus of the fourth aspect, even in a refrigeration cycle apparatus configured to be able to switch refrigerant circuits, it is possible to suppress a decrease in productivity.

[0042] The above and other objects, features, and advantages of the present disclosure will become more apparent from the following detailed description taken in conjunction with the accompanying drawings.

[0014] Fig. 1 is a schematic overall configuration diagram showing a refrigerant flow in a cooling mode of a refrigeration cycle device of a first embodiment.

[0015] Fig. 2 is a schematic configuration diagram showing an air flow in a cooling mode of an air distribution unit of the first embodiment.

[0016] Fig. 3 is a block diagram showing an electrical control unit of a vehicle air conditioner of the first embodiment.

[0017] Fig. 4 is a Mollier diagram showing a change in refrigerant state in a single cooling mode of the refrigeration cycle device of the first embodiment.

[0018] Fig. 5 is a schematic overall configuration diagram showing a refrigerant flow in a heating mode of the refrigeration cycle device of the first embodiment.

[0019] Fig. 6 is a schematic configuration diagram showing an air flow in a heating mode of the air distribution unit of the first embodiment.

[0020] Fig. 7 is a Mollier diagram showing a change in refrigerant state in a heating mode of the refrigeration cycle device of the first embodiment.

[0021] Fig. 8 is a schematic overall configuration diagram showing a refrigerant flow in a dehumidifying heating mode of the refrigeration cycle device of the first embodiment.

[0022] Fig. 9 is a schematic configuration diagram showing an air flow in a dehumidifying heating mode of the air distribution unit of the first embodiment.

[0023] Fig. 10 is a Mollier diagram showing a change in refrigerant state in a dehumidifying heating mode of the refrigeration cycle device of the first embodiment. Fig. 10 is a schematic diagram showing an air flow in a heating mode of an air distribution unit of a second embodiment. Fig. 11 is a schematic overall diagram showing a refrigerant flow in a heating mode of a refrigeration cycle device of a third embodiment. Fig. 12 is a Mollier diagram showing a change in the state of a refrigerant in a heating mode of a refrigeration cycle device of a third embodiment. Fig. 13 is a schematic overall diagram of a refrigeration cycle device of a fourth embodiment. Fig. 14 is a Mollier diagram showing a change in the state of a refrigerant in a cooling mode of a refrigeration cycle device of a fourth embodiment.

[0043] Hereinafter, multiple embodiments for carrying out the present disclosure will be described with reference to the drawings. In each embodiment, parts corresponding to matters described in the preceding embodiment will be assigned the same reference numerals, and duplicate descriptions may be omitted. In each embodiment, when only a part of the configuration is described, other previously described embodiments may be applied to the other parts of the configuration. In addition to combinations of parts that are specifically specified as being combinable in each embodiment, it is also possible to partially combine embodiments even if not specified, as long as there is no particular problem with the combination.

[0044] First Embodiment A first embodiment of a refrigeration cycle device according to the present disclosure will be described using Figures 1 to 10. In this embodiment, a refrigeration cycle device 10 according to the present disclosure is applied to a vehicle air conditioner 1 mounted on an electric vehicle. The vehicle air conditioner 1 of this embodiment conditions the air inside the vehicle cabin, which is the space to be air-conditioned, and also regulates the temperature of on-board equipment. Therefore, the vehicle air conditioner 1 can be called an air conditioner with an on-board equipment temperature regulation function, or an on-board equipment temperature regulation device with an air conditioning function.

[0045] Specifically, the vehicle air conditioner 1 regulates the temperature of a battery 70 as an on-board device. The battery 70 is a secondary battery that stores power to be supplied to a plurality of electrically operated on-board devices. The battery 70 is an assembled battery formed by electrically connecting a plurality of stacked battery cells in series or parallel. In this embodiment, the battery cells are lithium-ion batteries.

[0046] The battery 70 generates heat during operation (i.e., during charging and discharging). The output of the battery 70 is likely to decrease at low temperatures, and deterioration is likely to progress at high temperatures. For this reason, the temperature of the battery 70 needs to be maintained within an appropriate temperature range (in this embodiment, 15°C or higher and 55°C or lower). Therefore, in the electric vehicle of this embodiment, the temperature of the battery 70 is adjusted using the vehicle air conditioner 1.

[0047] The vehicle air conditioner 1 includes a refrigeration cycle device 10, a low-temperature side heat medium circuit 40, an air distribution unit 50, a control device 60, and the like.

[0048] First, a refrigeration cycle device 10 will be described with reference to Fig. 1. The refrigeration cycle device 10 adjusts the temperature of the air blown into the vehicle cabin and the low-temperature side heat medium circulating through a low-temperature side heat medium circuit 40. Furthermore, the refrigeration cycle device 10 is configured to be able to switch the refrigerant circuit according to various operation modes described below in order to air-condition the vehicle cabin and adjust the temperature of on-board equipment.

[0049] The refrigeration cycle device 10 uses carbon dioxide (i.e., R744), which is a natural refrigerant, as a refrigerant. The refrigeration cycle device 10 configures a supercritical refrigeration cycle in which the refrigerant pressure on the high-pressure side is equal to or higher than the critical pressure of the refrigerant.

[0050] The refrigerant is mixed with refrigeration oil to lubricate the compressor 11. As the refrigeration oil, oil containing PAG (i.e., polyalkylene glycol) that is compatible with the liquid-phase refrigerant can be used. A portion of the refrigeration oil circulates through the refrigeration cycle device 10 together with the refrigerant.

[0051] The compressor 11 is a combined compressor in which a first compression section 111 and a second compression section 112 are housed in the same housing. The first compression section 111 and the second compression section 112 compress and discharge the refrigerant in the refrigeration cycle apparatus 10.

[0052] The first compression section 111 and the second compression section 112 are electric compressors in which fixed displacement compression mechanisms, each having a fixed displacement, are rotationally driven by an electric motor. In the compressor 11 of this embodiment, the compression mechanisms of the first compression section 111 and the second compression section 112 are rotationally driven by different electric motors.

[0053] Furthermore, the compressor 11 of this embodiment employs rotary compression mechanisms as the compression mechanisms of the first compression section 111 and the second compression section 112. The rotary compression mechanism offers a high degree of freedom in forming refrigerant passages within the housing, and is therefore effective in preventing an increase in size and weight of the combined compressor.

[0054] The housing is formed with a first intake port 111a through which refrigerant is drawn into the first compression section 111 and a first discharge port 111b through which the refrigerant compressed by the first compression section 111 is discharged. The housing is further formed with a second intake port 112a through which refrigerant is drawn into the second compression section 112 and a second discharge port 112b through which the refrigerant compressed by the second compression section 112 is discharged.

[0055] The first and second discharge ports 111b, 112b are each provided with a discharge valve (not shown). Therefore, even when the first and second compression sections 111, 112 are not operating, the refrigerant does not flow back into the housing through the first and second discharge ports 111b, 112b. The rotation speeds (i.e., refrigerant discharge capacities) of the first and second compression sections 111, 112 are controlled by control signals output from a control device 60 (described later).

[0056] The first discharge port 111b of the compressor 11 is connected to a refrigerant inlet side of a first heat exchanger 12. The first heat exchanger 12 is disposed in an air passage formed by an air distribution unit 50, which will be described later.

[0057] The first heat exchanger 12 exchanges heat between the refrigerant discharged from the first compression section 111 and either inside air (i.e., air inside the vehicle cabin) or outside air (i.e., air outside the vehicle cabin) blown by a blower (not shown). The first heat exchanger 12 is a heat dissipation section that dissipates heat contained in the refrigerant discharged from the first compression section 111 to the outside air or inside air.

[0058] The inlet side of a first three-way joint 13a is connected to the refrigerant outlet of the first heat exchanger 12. The first three-way joint 13a is a three-way joint having three inlet and outlet ports that communicate with each other. The first three-way joint 13a may be a joint formed by joining multiple pipes or a joint formed by providing multiple refrigerant passages in a metal block or a resin block.

[0059] Furthermore, the refrigeration cycle apparatus 10 includes a second three-way joint 13b to an eighth three-way joint 13h, as will be described later. The second three-way joint 13b to the eighth three-way joint 13h have the same basic configuration as the first three-way joint 13a. Furthermore, the basic configuration of each three-way joint described in the embodiments below is also the same as the first three-way joint 13a.

[0060] The three-way joint can branch the refrigerant flow when one of the three inlet / outlet ports is used as an inlet and the remaining two are used as outlet ports, and can merge the refrigerant flow when two of the three inlet / outlet ports are used as inlet ports and the remaining one is used as an outlet port.

[0061] One outlet of the first three-way joint 13 a is connected to one inlet of the second three-way joint 13 b, and the other outlet of the first three-way joint 13 a is connected to the inlet of the heating expansion valve 14 a.

[0062] The heating expansion valve 14a is a first pressure reducing unit that reduces the pressure of the refrigerant flowing out from the other outlet of the first three-way joint 13a (i.e., the other refrigerant branched at the first three-way joint 13a) during a heating mode, etc., which will be described later. Furthermore, the heating expansion valve 14a is a first flow rate adjusting unit that adjusts the refrigerant flow rate (in this embodiment, the mass flow rate) flowing from the first heat exchanger 12 into the second heat exchanger 16 during a heating mode, etc.

[0063] The heating expansion valve 14a is an electric variable throttle mechanism having a first valve body 15a that changes the throttle opening and an electric actuator (specifically, a stepping motor or a brushless DC motor) that serves as a drive unit that displaces the first valve body 15a. The operation of the heating expansion valve 14a is controlled by control pulses output from the control device 60.

[0064] The heating expansion valve 14a has a fully open function that functions as a simple refrigerant passage without exerting any refrigerant decompression effect by fully opening the throttle opening of the first valve body 15a, and also has a fully closed function that closes the refrigerant passage by fully closing the throttle opening of the first valve body 15a.

[0065] Furthermore, as will be described later, the refrigeration cycle apparatus 10 is equipped with a cooling expansion valve 14b, an intermediate-pressure expansion valve 14c, and a cooling expansion valve 14d. The basic configuration of these expansion valves is the same as that of the heating expansion valve 14a. Therefore, the cooling expansion valve 14b, the intermediate-pressure expansion valve 14c, and the cooling expansion valve 14d each have a second valve body 15b, a third valve body 15c, and a fourth valve body 15d that are similar to the first valve body 15a.

[0066] The heating expansion valve 14a to the cooling expansion valve 14d can switch the refrigerant circuit of the refrigeration cycle device 10 by the first valve body portion 15a to the fourth valve body portion 15d fulfilling the fully closing function. Therefore, the first valve body portion 15a to the fourth valve body portion 15d also function as a refrigerant circuit switching unit.

[0067] Of course, the heating expansion valve 14a to the cooling expansion valve 14d may be formed by combining a variable throttle mechanism that does not have a full-closing function with an on-off valve that opens and closes the throttle passage. In this case, each on-off valve serves as a refrigerant circuit switching unit.

[0068] An outlet of the heating expansion valve 14 a is connected to one inlet side of a third three-way joint 13 c, and the other inlet side of the third three-way joint 13 c is connected to the second discharge port 112 b side of the compressor 11.

[0069] The outlet of the third three-way joint 13c is connected to the refrigerant inlet side of the second heat exchanger 16. The second heat exchanger 16 is disposed in an air passage formed by the air distribution unit 50. The second heat exchanger 16 exchanges heat between the refrigerant flowing out from the third three-way joint 13c and outside air blown by a blower (not shown).

[0070] More specifically, the second heat exchanger 16 functions as a heat-dissipating heat exchanger that dissipates heat from the refrigerant to the outside air during a cooling mode, which will be described later. The second heat exchanger 16 also functions as a heat-absorbing heat exchanger that absorbs heat from the outside air into the refrigerant during a heating mode, etc. Therefore, the second heat exchanger 16 is a heat-absorbing / heat-dissipating section that absorbs or dissipates heat from the refrigerant that has flowed out from the third three-way joint 13c.

[0071] The inlet side of a fourth three-way joint 13d is connected to the refrigerant outlet of the second heat exchanger 16. The inlet side of the intermediate-pressure expansion valve 14c is connected to one outlet of the fourth three-way joint 13d. The inlet side of the high-pressure refrigerant passage of the internal heat exchanger 17 is connected to the other outlet of the fourth three-way joint 13d. Therefore, the fourth three-way joint 13d is a branching part that branches the flow of refrigerant flowing out of the second heat exchanger 16.

[0072] The intermediate-pressure expansion valve 14c is a third pressure reducing unit that reduces the pressure of the refrigerant flowing out from one outlet of the fourth three-way joint 13d (i.e., one of the refrigerant branches at the fourth three-way joint 13d) during the cooling mode, etc. Furthermore, the intermediate-pressure expansion valve 14c is a third flow rate adjusting unit that adjusts the flow rate of the refrigerant drawn from the fourth three-way joint 13d side into the second suction port 112a of the compressor 11 during the cooling mode, etc.

[0073] The outlet of the intermediate pressure expansion valve 14c is connected to the other inlet side of the second three-way joint 13b. The outlet of the second three-way joint 13b is connected to the second suction port 112a side of the compressor 11.

[0074] The internal heat exchanger 17 has a high-pressure refrigerant passage and a low-pressure refrigerant passage, and exchanges heat between the high-pressure refrigerant flowing through the high-pressure refrigerant passage and the low-pressure refrigerant flowing through the low-pressure refrigerant passage. The refrigerant flowing through the other outlet of the fourth three-way joint 13d (i.e., the other refrigerant branched by the fourth three-way joint 13d) flows through the high-pressure refrigerant passage. The refrigerant drawn into the first suction port 111a of the compressor 11 flows through the low-pressure refrigerant passage.

[0075] Therefore, in the cooling mode, the internal heat exchanger 17 serves as a high-low pressure internal heat exchange section that exchanges heat between the refrigerant flowing out of the second heat exchanger 16 and the refrigerant drawn into the first compression section 111 .

[0076] An inlet side of a fifth three-way joint 13e is connected to an outlet of the high-pressure refrigerant passage of the internal heat exchanger 17. An inlet side of a sixth three-way joint 13f is connected to one outlet side of the fifth three-way joint 13e. An inlet side of an on-off valve 15e is connected to the other outlet side of the fifth three-way joint 13e. An outlet side of the on-off valve 15e is connected to one inlet side of a seventh three-way joint 13g.

[0077] The on-off valve 15e opens and closes the refrigerant flow path from the other outlet of the fifth three-way joint 13e to one inlet of the seventh three-way joint 13g. The on-off valve 15e is a solenoid valve whose opening and closing operation is controlled by a control voltage output from the control device 60. Furthermore, the basic configuration of each on-off valve described in the embodiments below is also the same as that of the on-off valve 15e.

[0078] One outlet of the sixth three-way joint 13f is connected to the inlet side of the cooling expansion valve 14b, and the other outlet of the sixth three-way joint 13f is connected to the inlet side of the cooling expansion valve 14d.

[0079] The cooling expansion valve 14b is a second pressure reducing unit that reduces the pressure of the refrigerant flowing out from one outlet of the sixth three-way joint 13f (i.e., one of the refrigerant branches at the sixth three-way joint 13f) during the cooling mode, etc. Furthermore, the cooling expansion valve 14b is a second flow rate adjusting unit that adjusts the flow rate of the refrigerant flowing into the evaporator 18 during the cooling mode, etc.

[0080] The outlet of the cooling expansion valve 14b is connected to the refrigerant inlet side of the evaporator 18. The evaporator 18 is disposed in an air passage formed by the air distribution unit 50. The evaporator 18 exchanges heat between the refrigerant decompressed by the cooling expansion valve 14b and the air blown from a blower (not shown). The evaporator 18 is a heat absorption unit that cools the air blown by evaporating the refrigerant decompressed by the cooling expansion valve 14b to exert a heat absorption effect.

[0081] The cooling expansion valve 14d is a fourth pressure reducing unit that reduces the pressure of the refrigerant flowing out from the other outlet of the sixth three-way joint 13f (i.e., the other refrigerant branched at the sixth three-way joint 13f) during the operation mode for cooling the on-vehicle equipment. Furthermore, the cooling expansion valve 14d is a fourth flow rate adjusting unit that adjusts the flow rate of the refrigerant flowing into the chiller 19 during the operation mode for cooling the on-vehicle equipment.

[0082] The outlet of the cooling expansion valve 14d is connected to the inlet side of the refrigerant passage of the chiller 19. The chiller 19 exchanges heat between the refrigerant decompressed by the cooling expansion valve 14d and the low-temperature side heat medium circulating through the low-temperature side heat medium circuit 40. The chiller 19 is a cooling heat exchanger that cools the low-temperature side heat medium by evaporating the refrigerant decompressed by the cooling expansion valve 14d to exert a heat absorption effect.

[0083] Here, the heat absorption performance of the evaporator 18 and the heat absorption performance of the chiller 19 in this embodiment are different from each other. Specifically, the heat absorption performance of the evaporator 18 is set to be higher than the heat absorption performance of the chiller 19. The heat absorption performance can be defined as the amount of heat absorbed by the refrigerant when refrigerant at the same temperature and flow rate passes through the evaporator 18. Therefore, in this embodiment, the heat exchange capacity of the evaporator 18 is set to be higher than the heat exchange capacity of the chiller.

[0084] Furthermore, the heat exchange capacities of the first heat exchanger 12, the second heat exchanger 16, and the evaporator 18 are set so that the heat exchange capacity of the second heat exchanger 16 is higher than the heat exchange capacity of the first heat exchanger 12 and the heat exchange capacity of the evaporator 18. The heat exchange capacities of these heat exchangers can be set, for example, by adjusting the area of ​​the heat exchange core portion where heat exchange between the refrigerant and the air actually takes place.

[0085] One inlet side of an eighth three-way joint 13h is connected to the refrigerant outlet of the evaporator 18. The other inlet side of the eighth three-way joint 13h is connected to the refrigerant outlet of the refrigerant passage of the chiller 19. The other inlet side of the seventh three-way joint 13g is connected to the outlet of the eighth three-way joint 13h.

[0086] The outlet of the seventh three-way joint 13g is connected to the inlet side of the accumulator 20. The accumulator 20 is a low-pressure gas-liquid separation unit that separates the refrigerant flowing out from the seventh three-way joint 13g into gas and liquid phases and stores the separated liquid-phase refrigerant as surplus refrigerant for the cycle.

[0087] The gas-phase refrigerant outlet of the accumulator 20 is connected to the inlet side of the low-pressure refrigerant passage of the internal heat exchanger 17. The outlet of the low-pressure refrigerant passage of the internal heat exchanger 17 is connected to the first suction port 111a side of the compressor 11.

[0088] Next, the low-temperature side heat medium circuit 40 will be described. The low-temperature side heat medium circuit 40 is a heat medium circulation circuit that circulates the low-temperature side heat medium. In this embodiment, an ethylene glycol aqueous solution is used as the low-temperature side heat medium. The low-temperature side heat medium circuit 40 includes a heat medium passage for the chiller 19, a low-temperature side pump 41, a coolant passage 70a for the battery 70, a low-temperature side three-way valve 42, a low-temperature side radiator 44, and the like.

[0089] The low-temperature side pump 41 is a low-temperature side heat medium pumping unit that pumps the low-temperature side heat medium to the inlet side of the heat medium passage of the chiller 19. The low-temperature side pump 41 is an electric water pump whose rotation speed (i.e., pumping capacity) is controlled by a control voltage output from the control device 60.

[0090] The outlet of the heat medium passage of the chiller 19 is connected to the inlet side of the coolant passage 70a of the battery 70. The coolant passage 70a of the battery 70 is a coolant passage that cools the battery 70 by circulating the low-temperature heat medium that has flowed out from the chiller 19. In other words, the coolant passage 70a is a heat exchanger for cooling the battery 70 by exchanging heat between the low-temperature heat medium circulating through the heat medium flow path and the battery cells.

[0091] The cooling water passage 70a is formed inside the battery case that houses multiple stacked battery cells. The cooling water passage 70a is configured with multiple passages connected in parallel inside the battery case. This allows the cooling water passage 70a to cool all of the battery cells evenly.

[0092] The inlet side of the low-temperature side three-way valve 42 is connected to the outlet of the coolant passage 70a of the battery 70. The low-temperature side three-way valve 42 is an electric three-way flow control valve that has one inlet and two outlets and can continuously adjust the passage area ratio of the two outlets. The operation of the low-temperature side three-way valve 42 is controlled by a control signal output from the control device 60.

[0093] One outlet of the low-temperature side three-way valve 42 is connected to one inlet side of a heat medium three-way joint 43. The basic configuration of the heat medium three-way joint 43 is similar to that of the first three-way joint 13a for the refrigerant, etc. The other outlet of the low-temperature side three-way valve 42 is connected to the heat medium inlet side of a low-temperature side radiator 44.

[0094] The low-temperature side radiator 44 is an outside air heat exchanger for a heat medium that exchanges heat between the refrigerant flowing out from the coolant passage 70a and outside air blown by an outside air fan (not shown). The low-temperature side radiator 44 may be formed integrally with the second heat exchanger 16 and disposed in the air passage of the air distribution unit 50.

[0095] The heat medium outlet of the low-temperature side radiator 44 is connected to the other inlet side of the heat medium three-way joint 43. The outlet side of the heat medium three-way joint 43 is connected to the suction side of the low-temperature side pump 41.

[0096] Therefore, in the low-temperature side heat medium circuit 40, the low-temperature side three-way valve 42 allows the low-temperature side heat medium flowing out from the coolant passage 70a to flow into the heat medium passage of the chiller 19. As a result, the heat absorbed from the battery 70 by the low-temperature side heat medium in the coolant passage 70a can be absorbed by the low-pressure refrigerant in the chiller 19.

[0097] Furthermore, in the low-temperature side heat medium circuit 40, the low-temperature side three-way valve 42 allows the low-temperature side heat medium that flows out from the coolant passage 70a to flow into the low-temperature side radiator 44. This allows the heat absorbed by the low-temperature side heat medium from the battery 70 in the coolant passage 70a to be radiated to the outside air by the low-temperature side radiator 44.

[0098] Next, the air distribution unit 50 will be described with reference to Fig. 2. The air distribution unit 50 is a unit that integrates multiple components to exchange heat between the refrigerant circulating in the refrigeration cycle device 10 and the air, and to blow out the air after heat exchange to an appropriate location. The air distribution unit 50 is disposed in the drive unit chamber.

[0099] The drive unit compartment forms a space in which at least a portion of the equipment used to generate and adjust the drive force for the vehicle (e.g., an electric motor for driving the vehicle) is disposed. The drive unit compartment is located outside the vehicle interior.

[0100] The air distribution unit 50 has a casing 51 that forms an air passage through which the ventilation air to be blown into the vehicle cabin and the outside air circulate. The casing 51 is molded from a resin (e.g., polypropylene) that has a certain degree of elasticity and excellent strength. The casing 51 of this embodiment forms three air passages: a first air passage 50a, a second air passage 50b, and a third air passage 50c.

[0101] The first air passage 50a is provided with the second heat exchanger 16. An outside air inlet 52a for introducing outside air is formed at the most upstream portion of the first air passage 50a in the air flow direction. An outside air outlet for discharging the outside air that has passed through the second heat exchanger 16 to the outside of the vehicle cabin is formed at the most downstream portion of the first air passage 50a in the air flow direction. Therefore, the first air passage 50a is an outside air passage for circulating outside air.

[0102] The second air passage 50b is provided with a first heat exchanger 12. A second inside / outside air switching device 52b is provided at the most upstream portion of the second air passage 50b in the air flow direction. The second inside / outside air switching device 52b switches between introducing inside air and outside air into the second air passage 50b. The operation of the second inside / outside air switching device 52b is controlled by a control signal output from the control device 60.

[0103] The third air passage 50c is provided with an evaporator 18. A third inside / outside air switching device 52c is provided at the most upstream portion of the third air passage 50c in the air flow direction. The third inside / outside air switching device 52c switches between introducing inside air and outside air into the third air passage 50c. The basic configuration of the third inside / outside air switching device 52c is the same as that of the second inside / outside air switching device 52b.

[0104] The partition wall separating the second air passage 50b and the third air passage 50c has a communication hole 51a that connects the second air passage 50b and the third air passage 50c. The partition wall separating the second air passage 50b and the third air passage 50c has an air passage switching device 52d that switches the air passage by opening and closing the communication hole 51a.

[0105] Specifically, when the air-flow-path switching device 52d closes the communication hole 51a, the second air passage 50b and the third air passage 50c are switched to become independent air passages. When the air-flow-path switching device 52d opens the communication hole 51a, the air that has passed through the evaporator 18 disposed in the third air passage 50c is switched to an air passage that leads, via the communication hole 51a, to the upstream side of the first heat exchanger 12 disposed in the second air passage 50b.

[0106] Furthermore, the ventilation path switching device 52d of this embodiment also has the function of closing the inlet side of the second air passage 50b to allow air to flow from the third air passage 50c to the second air passage 50b. The operation of the ventilation path switching device 52d is controlled by a control signal output from the control device 60.

[0107] An interior air introduction device 52e is disposed at the most downstream air flow portion of the second air passage 50b and the third air passage 50c. The interior air introduction device 52e switches the air that has flowed through the second air passage 50b and the third air passage 50c between a ventilation path that guides the air into the vehicle cabin and a ventilation path that exhausts the air to the outside of the vehicle cabin. The operation of the interior air introduction device 52e is controlled by a control signal output from the control device 60.

[0108] Next, the electrical control unit of the vehicle air conditioner 1 will be described. The control device 60 has a well-known microcomputer including a CPU, ROM, RAM, etc., and its peripheral circuits. The control device 60 performs various calculations and processes based on control programs stored in the ROM. The control device 60 then controls the operation of various control target devices connected to the output side based on the results of the calculations and processes.

[0109] 3, a group of control sensors is connected to the input side of the control device 60. The group of control sensors includes an inside air temperature sensor 61a, an outside air temperature sensor 61b, a solar radiation sensor 61c, a first discharge refrigerant sensor 62a, a second intake refrigerant sensor 62b, a second discharge refrigerant sensor 62c, a first refrigerant sensor 62d, a second refrigerant sensor 62e, an evaporator temperature sensor 62f, a chiller-side temperature sensor 62g, a low-temperature side heat medium temperature sensor 63, an air conditioning air temperature sensor 64, a battery temperature sensor 65, and the like.

[0110] The inside air temperature sensor 61a is an inside air temperature detector that detects the inside air temperature (i.e., the temperature inside the vehicle cabin) Tr. The outside air temperature sensor 61b is an outside air temperature detector that detects the outside air temperature (i.e., the temperature outside the vehicle cabin) Tam. The solar radiation sensor 61c is an solar radiation amount detector that detects the amount of solar radiation As irradiating into the vehicle cabin.

[0111] The first discharge refrigerant sensor 62a is a first discharge refrigerant temperature / pressure detection unit that detects the first discharge refrigerant temperature Td1, which is the temperature of the first discharge refrigerant discharged from the first compression unit 111, and the first discharge refrigerant pressure Pd1, which is the pressure of the first discharge refrigerant.

[0112] The second intake refrigerant sensor 62b is a second intake refrigerant temperature / pressure detection unit that detects the second intake refrigerant temperature Ts2, which is the temperature of the second intake refrigerant sucked into the second compression unit 112, and the second intake refrigerant pressure Ps2, which is the pressure of the second intake refrigerant.

[0113] The second discharge refrigerant sensor 62c is a second discharge refrigerant temperature / pressure detection unit that detects the second discharge refrigerant temperature Td2, which is the temperature of the second discharge refrigerant discharged from the second compression unit 112, and the second discharge refrigerant pressure Pd2, which is the pressure of the second discharge refrigerant.

[0114] The first refrigerant sensor 62d is a first refrigerant temperature and pressure detection unit that detects the first refrigerant temperature Ti1, which is the temperature of the first refrigerant at the outlet side of the first heat exchanger 12, and the first refrigerant pressure Pi1, which is the pressure of the first refrigerant.

[0115] The second refrigerant sensor 62e is a second refrigerant temperature and pressure detection unit that detects the second refrigerant temperature Ti2, which is the temperature of the second refrigerant at the outlet side of the high-pressure refrigerant passage of the internal heat exchanger 17, and the second refrigerant pressure Pi2, which is the pressure of the second refrigerant.

[0116] In this embodiment, a detection unit in which a pressure detection unit and a temperature detection unit are integrated is used as the refrigerant sensor, but of course, a pressure detection unit and a temperature detection unit that are each configured as separate units may also be used.

[0117] The evaporator temperature sensor 62f is an evaporator temperature detection unit that detects the refrigerant evaporation temperature (evaporator temperature) Tefin in the evaporator 18. Specifically, the evaporator temperature sensor 62f detects the temperature of the heat exchange fins of the evaporator 18. The chiller-side temperature sensor 62g is a chiller-side refrigerant temperature detection unit that detects a chiller-side refrigerant temperature Tc, which is the temperature of the chiller outlet-side refrigerant flowing out from the refrigerant passage of the chiller 19.

[0118] The low-temperature-side heat medium temperature sensor 63 is a low-temperature-side heat medium temperature detection unit that detects a low-temperature-side heat medium temperature TWL, which is the temperature of the low-temperature-side heat medium flowing out from the coolant passage 70a of the battery 70. The air conditioning air temperature sensor 64 is an air conditioning air temperature detection unit that detects the temperature TAV of the air blown into the vehicle cabin from the air distribution unit 50.

[0119] The battery temperature sensor 65 is a battery temperature detection unit that detects the battery temperature TB, which is the temperature of the battery 70. The battery temperature sensor 65 has multiple temperature sensors and detects the temperature at multiple locations on the battery 70. This allows the control device 60 to detect the temperature difference and temperature distribution among the battery cells that make up the battery 70. The average value of the detection values ​​of the multiple temperature sensors is used as the battery temperature TB.

[0120] 3, an operation panel 69 located near the instrument panel at the front of the vehicle cabin is connected to the input side of the control device 60 via wire or wirelessly. Operation signals are input to the control device 60 from various operation switches provided on the operation panel 69. Specific examples of the various operation switches provided on the operation panel 69 include an auto switch, an air conditioner switch, an air volume setting switch, a temperature setting switch, etc.

[0121] The auto switch is an automatic control setting unit that sets or cancels automatic control operation of the vehicle air conditioner 1. The air conditioner switch is a cooling request unit that requests cooling of the blown air by the evaporator 18. The air volume setting switch is an air volume setting unit that manually sets the volume of the blown air to be blown into the vehicle compartment. The temperature setting switch is a temperature setting unit that sets the set temperature Tset in the vehicle compartment.

[0122] The control device 60 of this embodiment is an integrated unit that controls various control target devices connected to the output side. Therefore, the configuration (hardware and software) that controls the operation of each control target device constitutes the control unit that controls the operation of each control target device.

[0123] For example, in the control device 60, the component that controls the refrigerant discharge capacity of the first compression section 111 constitutes a first discharge capacity control section 60a, the component that controls the refrigerant discharge capacity of the second compression section 112 constitutes a second discharge capacity control section 60b, and the component that controls the operation of the refrigerant circuit switching section constitutes a refrigerant circuit control section 60c.

[0124] Next, the operation of the vehicle air conditioner 1 of this embodiment configured as described above will be described. The vehicle air conditioner 1 of this embodiment switches between various operating modes to condition the air in the vehicle cabin and regulate the temperature of the battery 70. The switching of operating modes is performed by executing a control program stored in advance in the control device 60.

[0125] The control program is executed not only when the start switch (so-called ignition switch) of the vehicle system is turned on and the vehicle system is running, but also when the battery 70 is being charged from an external power source, etc. The control program performs air conditioning in the vehicle cabin when the auto switch is turned on.

[0126] The control program reads detection signals from the control sensors and operation signals from the operation panel 69. Based on the read detection signals and operation signals, the control program calculates a target outlet temperature TAO. The target outlet temperature TAO is the target temperature of the air to be blown into the vehicle cabin. Based on the detection signals, operation signals, target outlet temperature TAO, etc., the control program selects an operation mode and controls the operation of various controlled devices according to the selected operation mode.

[0127] Thereafter, the control routines, such as reading the above-mentioned detection signals and operation signals, calculating the target blown air temperature TAO, selecting the operation mode, and controlling the various controlled devices, are repeated at each predetermined control cycle until the termination condition of the control program is met.

[0128] The target air temperature TAO is calculated using the following formula F1: TAO=Kset×Tset−Kr×Tr−Kam×Tam−Ks×As+C (F1) Tset is the set temperature inside the vehicle cabin set by the temperature setting switch. Tr is the inside air temperature detected by the inside air temperature sensor 61a. Tam is the outside air temperature detected by the outside air temperature sensor 61b. As is the amount of solar radiation detected by the solar radiation amount sensor 61c. Kset, Kr, Kam, and Ks are control gains, and C is a correction constant. Each operating mode will be described below.

[0129] (a) Cooling Mode The cooling mode is an operating mode in which cooled air is blown into the vehicle cabin to cool the interior of the vehicle. The cooling mode is likely to be selected when the auto switch and the air conditioner switch are on, the outside air temperature Tam is relatively high (in this embodiment, 25°C or higher), or the target outlet temperature TAO is relatively low.

[0130] The cooling modes include a standalone cooling mode and a cooling / cooling mode. The standalone cooling mode is an operation mode in which the vehicle cabin is cooled without cooling the battery 70 using the cooling capacity of the refrigeration cycle device 10. The cooling / cooling mode is an operation mode in which the battery 70 is cooled using the cooling capacity of the refrigeration cycle device 10 and the vehicle cabin is cooled.

[0131] Here, the control device 60 has a cooling necessity determination unit that determines whether or not it is necessary to cool the battery 70 using the cooling capacity of the refrigeration cycle device 10. Then, when the cooling necessity determination unit determines that it is necessary to cool the battery 70, the control device 60 switches to an operation mode that cools the battery.

[0132] More specifically, when the battery temperature TB detected by the battery temperature sensor 65 is equal to or higher than a predetermined reference cooling temperature KTB, the cooling necessity determination unit determines that it is necessary to cool the battery 70 using the cooling capacity of the refrigeration cycle device 10. This also applies to other operating modes.

[0133] (a-1) Cooling Only Mode In the refrigeration cycle apparatus 10 in the cooling only mode, the control device 60 fully closes the heating expansion valve 14a, fully closes the intermediate-pressure expansion valve 14c or throttles the intermediate-pressure expansion valve 14c to reduce the refrigerant pressure, throttles the cooling expansion valve 14b, and fully closes the cooling expansion valve 14d. The control device 60 also closes the on-off valve 15e. The control device 60 also controls both the first compression section 111 and the second compression section 112 to exert their refrigerant discharge capacities.

[0134] 1 , in the refrigeration cycle apparatus 10 in the cooling-only mode, the refrigerant discharged from the first discharge port 111b of the compressor 11 circulates in this order through the first heat exchanger 12 and the second suction port 112a of the compressor 11. Furthermore, the refrigerant discharged from the second discharge port 112b circulates in this order through the second heat exchanger 16, the intermediate-pressure expansion valve 14c, and the second suction port 112a of the compressor 11, and the refrigerant discharged from the second discharge port 112b of the compressor 11 circulates in this order through the second heat exchanger 16, the high-pressure refrigerant passage of the internal heat exchanger 17, the cooling expansion valve 14b, the evaporator 18, the accumulator 20, the low-pressure refrigerant passage of the internal heat exchanger 17, and the first suction port 111a of the compressor 11.

[0135] The control device 60 also controls the refrigerant discharge capacity of the first compression section 111 so that the pressure of the refrigerant drawn into the second compression section 112 is equal to or higher than the critical pressure of the refrigerant, i.e., so that the refrigerant drawn into the second compression section 112 is in a supercritical state. The control device 60 detects the state of the refrigerant drawn into the second compression section 112 using the second suction refrigerant temperature Ts2 and the second suction refrigerant pressure Ps2 detected by the second suction refrigerant sensor 62b.

[0136] The control device 60 also controls the refrigerant discharge capacity of the second compression section 112 so that the evaporator temperature Tefin detected by the evaporator temperature sensor 62f approaches the target evaporator temperature TEO. The target evaporator temperature TEO is determined based on the target outlet temperature TAO by referring to a control map stored in advance in the control device 60.

[0137] In the control map, the target evaporator temperature TEO is increased as the target air outlet temperature TAO increases. The control map also determines the target evaporator temperature TEO within a range that can prevent frost formation on the evaporator 18.

[0138] The control device 60 also controls the throttle opening of the intermediate-pressure expansion valve 14c so that the second discharge refrigerant temperature Td2 detected by the second discharge refrigerant sensor 62c is equal to or lower than a reference temperature KTd2. The reference temperature KTd2 is set to a temperature lower than the heat-resistant temperature of the second compression section 112. Therefore, under operating conditions where the temperature of the refrigerant flowing out of the first heat exchanger 12 is sufficiently low, the control device 60 may fully close the intermediate-pressure expansion valve 14c.

[0139] The control device 60 also controls the throttle opening of the cooling expansion valve 14b so that the second refrigerant pressure Pi2 detected by the second refrigerant sensor 62e approaches the target high-pressure PDO2. The target high-pressure PDO2 is determined based on the outside air temperature Tam and the second discharge refrigerant temperature Td2, with reference to a control map pre-stored in the control device.

[0140] In the control map, the target high-pressure PDO2 is determined so that the coefficient of performance (ie, COP) of the refrigeration cycle device 10 approaches a maximum value.

[0141] In the low-temperature side heat medium circuit 40 in the single cooling mode, the control device 60 operates the low-temperature side pump 41 so as to exert a predetermined reference pumping capacity. The control device 60 also controls the operation of the low-temperature side three-way valve 42 so that the low-temperature side heat medium temperature TWL detected by the low-temperature side heat medium temperature sensor 63 approaches a predetermined reference low-temperature side heat medium temperature KTWL.

[0142] In the air distribution unit 50 in the sole cooling mode, the control device 60 operates a predetermined fan (not shown). As shown in Fig. 2, the control device 60 controls the operation of the second inside / outside air switching device 52b so that outside air is introduced into the second air passage 50b. In response to an operation signal or the like, the control device 60 controls the operation of the third inside / outside air switching device 52c so that outside air or inside air is introduced into the third air passage 50c.

[0143] The control device 60 also controls the operation of the air passage switching device 52d to close the communication hole 51a. The control device 60 also controls the operation of the interior air introducing device 52e to discharge the outside air that has passed through the first heat exchanger 12 to the outside of the vehicle cabin and introduce the blown air that has passed through the evaporator 18 into the vehicle cabin. The control device 60 also controls the operation of other devices that are subject to control as appropriate.

[0144] Therefore, in the refrigeration cycle device 10 in the single cooling mode, the state of the refrigerant changes as shown in the Mollier diagram of FIG.

[0145] That is, the refrigerant discharged from the first compression section 111 (point a4 in FIG. 4) flows into the first heat exchanger 12. The refrigerant that flows into the first heat exchanger 12 dissipates heat to the outside air flowing through the second air passage 50b, thereby reducing its enthalpy. The refrigerant that flows out of the first heat exchanger 12 merges with the refrigerant that has been decompressed by the intermediate-pressure expansion valve 14c (point e4 in FIG. 4), and is drawn into the second compression section 112 and compressed (from point j4 to point c4 in FIG. 4).

[0146] The refrigerant discharged from the second compression section 112 (point c4 in FIG. 4) flows into the second heat exchanger 16. The refrigerant that flows into the second heat exchanger 16 dissipates heat to the outside air flowing through the first air passage 50a, thereby reducing the enthalpy (from point c4 to point d4 in FIG. 4). The flow of the refrigerant that flows out of the second heat exchanger 16 is branched at the fourth three-way joint 13d.

[0147] One of the refrigerant branches at the fourth three-way joint 13d is decompressed by the intermediate-pressure expansion valve 14c (from point d4 to point e4 in FIG. 4 ). The refrigerant decompressed by the intermediate-pressure expansion valve 14c joins with the refrigerant flowing out of the first heat exchanger 12 and is drawn into the second compression section 112.

[0148] However, when the intermediate pressure expansion valve 14c is fully closed, the refrigerant flow is not branched at the fourth three-way joint 3d, i.e., the state of the refrigerant does not change from point d4 to point e4, or from point e4 to point j4 in Figure 4.

[0149] The other refrigerant branched at the fourth three-way joint 13d flows into the high-pressure refrigerant passage of the internal heat exchanger 17. The refrigerant that flows into the high-pressure refrigerant passage of the internal heat exchanger 17 exchanges heat with the refrigerant flowing through the low-pressure refrigerant passage, thereby reducing its enthalpy (from point d4 to point f4 in FIG. 4). The refrigerant that flows out of the high-pressure refrigerant passage of the internal heat exchanger 17 is decompressed by the cooling expansion valve 14b (from point f4 to point g4 in FIG. 4).

[0150] The refrigerant decompressed by the cooling expansion valve 14b flows into the evaporator 18. The refrigerant that flows into the evaporator 18 evaporates by heat exchange with the outside air or the inside air flowing through the third air passage 50c (from point g4 to point h4 in FIG. 4). This cools the outside air or the inside air passing through the evaporator 18. The refrigerant that flows out of the evaporator 18 flows into the accumulator 20 and is separated into gas and liquid.

[0151] The gas phase refrigerant separated in the accumulator 20 flows into the low-pressure refrigerant passage of the internal heat exchanger 17. The refrigerant that flows into the low-pressure refrigerant passage of the internal heat exchanger 17 exchanges heat with the refrigerant flowing through the high-pressure refrigerant passage, increasing the enthalpy (from point h4 to point i4 in FIG. 4). The refrigerant that flows out of the low-pressure refrigerant passage of the internal heat exchanger 17 is drawn into the first compression section 111 and compressed (from point i4 to point a4 in FIG. 4).

[0152] In other words, the single cooling mode is a first operating mode in which the heat contained in the refrigerant is dissipated to the outside air in the first heat exchanger 12 and the second heat exchanger 16, and the heat contained in the outside air or inside air, which is the object to be cooled, is absorbed by the refrigerant in the evaporator 18, thereby cooling the outside air or inside air.

[0153] In the low-temperature side heat medium circuit 40 in the single cooling mode, the low-temperature side heat medium pumped from the low-temperature side pump 41 flows into the heat medium passage of the chiller 19. The heat medium that has flowed into the heat medium passage of the chiller 19 flows out of the chiller 19 without any change in temperature, because no refrigerant is circulating in the refrigerant passage of the chiller 19.

[0154] The heat medium flowing out of chiller 19 flows into coolant passage 70a of battery 70, thereby cooling battery 70. The heat medium flowing out of coolant passage 70a flows out to one inlet side of heat medium three-way joint 43 and the heat medium inlet side of low-temperature side radiator 44, depending on the opening degree of low-temperature side three-way valve 42.

[0155] The heat medium that flows into the low-temperature side radiator 44 dissipates heat into the outside air. The heat medium that flows out of the low-temperature side radiator 44 flows into the other inlet of the heat medium three-way joint 43. The heat medium that flows out of the heat medium three-way joint 43 is sucked into the low-temperature side pump 41 and is pumped toward the heat medium passage of the chiller 19.

[0156] In the air distribution unit 50 in the sole cooling mode, the outside air or the inside air introduced into the third air passage 50c via the third inside / outside air switching device 52c is cooled by the evaporator 18. The outside air or the inside air cooled by the evaporator 18 is blown into the vehicle cabin via the interior introducing device 52e as ventilation air to be sent into the vehicle cabin, thereby realizing cooling of the vehicle cabin.

[0157] (a-2) Cooling / air-conditioning mode The cooling / air-conditioning mode is selected when the cooling necessity determination unit determines that it is necessary to cool the battery 70 using the cooling capacity of the refrigeration cycle device 10 while the single cooling mode is being executed.

[0158] In the refrigeration cycle apparatus 10 in the cooling / cooling mode, the control device 60 fully closes the heating expansion valve 14a, throttles or fully closes the intermediate-pressure expansion valve 14c, throttles the cooling expansion valve 14b, and throttles the cooling expansion valve 14d. The control device 60 also closes the on-off valve 15e. The control device 60 also controls both the first compression section 111 and the second compression section 112 to exert their refrigerant discharge capacities.

[0159] Therefore, in the refrigeration cycle device 10 in the cooling / cooling mode, the refrigerant is switched to a refrigerant circuit in which the refrigerant circulates in the same manner as in the single cooling mode. Furthermore, as shown by the bold dashed line in Figure 1, the other refrigerant branched at the sixth three-way joint 13f is switched to a refrigerant circuit in which the refrigerant flows in this order through the cooling expansion valve 14d, the chiller 19, and the eighth three-way joint 13h.

[0160] That is, in the refrigeration cycle apparatus 10 in the cooling / cooling mode, a multi-stage pressure-boosting refrigeration cycle is configured in which the refrigerant is compressed in stages in both the low-stage compression section 111 and the high-stage compression section 112. Furthermore, in the refrigeration cycle apparatus 10 in the cooling / cooling mode, the evaporator 18 and the chiller 19 are switched to a refrigerant circuit of the first operation mode in which they are connected in parallel with respect to the refrigerant flow.

[0161] The control device 60 also controls the throttle opening of the cooling expansion valve 14d so that the throttle opening becomes a predetermined throttle opening for the cooling / air-conditioning mode. The control device 60 also controls the operation of other control target devices in the same way as in the single cooling mode.

[0162] Therefore, in the refrigeration cycle device 10 in the cooling / air-conditioning mode, a multi-stage pressure-boosting refrigeration cycle is configured in which the first heat exchanger 12 and the second heat exchanger 16 function as heat exchangers for heat dissipation, and the evaporator 18 and chiller 19 function as heat exchangers for evaporation.

[0163] That is, the cooling / air-conditioning mode is a first operating mode in which the heat of the refrigerant is dissipated to the outside air in the first heat exchanger 12 and the second heat exchanger 16, and the heat of the outside air or the inside air, which is the object to be cooled, is absorbed by the refrigerant in the evaporator 18, thereby cooling the outside air or the inside air. Furthermore, the cooling / air-conditioning mode is an operating mode in which the heat of the low-temperature side heat medium is absorbed by the chiller 19, thereby cooling the low-temperature side heat medium.

[0164] In the low-temperature side heat medium circuit 40 in the cooling / cooling mode, the low-temperature side heat medium pumped from the low-temperature side pump 41 flows into the heat medium passage of the chiller 19. The low-temperature side heat medium that has flowed into the heat medium passage of the chiller 19 absorbs heat from the refrigerant and is cooled. The low-temperature side heat medium cooled by the chiller 19 flows into the coolant passage 70a of the battery 70. This cools the battery 70. Other operations are the same as in the single cooling mode.

[0165] In the air distribution unit 50 in the cooling / air-conditioning mode, the outside air or the inside air introduced into the third air passage 50c is cooled by the evaporator 18 and blown into the passenger compartment as ventilation air, as in the single cooling mode, thereby realizing cooling of the passenger compartment.

[0166] (b) Heating Mode The heating mode is an operating mode in which heated air is blown into the vehicle cabin to heat the interior of the vehicle. The heating mode is likely to be selected when the auto switch and air conditioner switch are on and the outside air temperature Tam is relatively low (in this embodiment, less than 10°C).

[0167] Therefore, in the heating mode of this embodiment, the vehicle cabin is heated without cooling the battery 70 using the cooling capacity of the refrigeration cycle device 10. In other words, the vehicle air conditioning device 1 of this embodiment is not provided with an operation mode in which the battery 70 is cooled using the cooling capacity of the refrigeration cycle device 10 and the vehicle cabin is heated.

[0168] In the heating mode of the refrigeration cycle apparatus 10, the control device 60 throttles the heating expansion valve 14a, fully closes the intermediate-pressure expansion valve 14c, fully closes the cooling expansion valve 14b, and fully closes the cooling expansion valve 14d. The control device 60 also opens the on-off valve 15e. The control device 60 also causes the first compression section 111 to exert its refrigerant discharge capacity and stops the second compression section 112.

[0169] Therefore, in the refrigeration cycle apparatus 10 in the heating mode, as shown by the thick solid line in Figure 5, the refrigerant discharged from the first discharge port 111b of the compressor 11 is switched to a refrigerant circuit for the second operation mode in which the refrigerant circulates in this order through the first heat exchanger 12, the heating expansion valve 14a, the second heat exchanger 16, the high-pressure refrigerant passage of the internal heat exchanger 17, the accumulator 20, the low-pressure refrigerant passage of the internal heat exchanger 17, and the first suction port 111a of the compressor 11.

[0170] The controller 60 also controls the refrigerant discharge capacity of the first compression section 111 so that the second refrigerant temperature Ti2 detected by the second refrigerant sensor 62e approaches a target second refrigerant temperature TiO2. The target second refrigerant temperature TiO2 is determined based on the target outlet temperature TAO and the outside air temperature T am by referring to a control map previously stored in the controller 60.

[0171] In the control map, the target second refrigerant temperature TiO2 is decreased as the target blow-out temperature TAO increases, and the control map also determines the target second refrigerant temperature TiO2 to be a value lower than the outside air temperature Tam.

[0172] The control device 60 also controls the throttle opening of the heating expansion valve 14a so that the first refrigerant pressure Pi1 detected by the first refrigerant sensor 62d approaches the target high-pressure PDO1. The target high-pressure PDO1 is determined based on the outside air temperature Tam and the first discharge refrigerant temperature Td1 detected by the first discharge refrigerant sensor 62a, with reference to a control map pre-stored in the control device.

[0173] In the control map, the target high pressure PDO1 is determined so that the COP of the refrigeration cycle device 10 approaches the maximum value.

[0174] In the low-temperature side heat medium circuit 40 in the heating mode, the control device 60 controls the operation of each component of the low-temperature side heat medium circuit 40 in the same manner as in the single cooling mode.

[0175] In the air distribution unit 50 in the heating mode, the control device 60 operates a predetermined blower (not shown). In addition, the control device 60 controls the operation of the second inside / outside air switching device 52b so that inside air is introduced into the second air passage 50b, as shown in FIG.

[0176] The control device 60 also controls the operation of the ventilation path switching device 52d so as to close the communication hole 51a. The control device 60 also controls the operation of the interior air introducing device 52e so as to introduce the blown air that has passed through the first heat exchanger 12 into the vehicle interior. Furthermore, the control device 60 also controls the operation of other control target devices as appropriate.

[0177] Therefore, in the refrigeration cycle apparatus 10 in the heating mode, the state of the refrigerant changes as shown in the Mollier diagram of Fig. 7. In Fig. 7, the state of the refrigerant at the locations equivalent in the cycle configuration to the Mollier diagram of Fig. 4, which describes the cooling-only mode, is indicated by the same reference characters (alphabet) as in Fig. 4, with only the subscripts (numbers) changed to match the diagram numbers. This also applies to the Mollier diagrams in the following embodiments.

[0178] That is, the refrigerant discharged from the first compression section 111 (point a7 in FIG. 7 ) flows into the first heat exchanger 12. The refrigerant that flows into the first heat exchanger 12 dissipates heat to the inside air flowing through the second air passage 50b, thereby reducing the enthalpy (from point a7 to point b7 in FIG. 7 ). This heats the air that is blown into the vehicle cabin. The refrigerant that flows out of the first heat exchanger 12 is decompressed by the heating expansion valve 14a (from point b7 to point c7 in FIG. 7 ).

[0179] The refrigerant decompressed by the heating expansion valve 14a flows into the second heat exchanger 16. The refrigerant that flows into the second heat exchanger 16 absorbs heat from the outside air flowing through the first air passage 50a and evaporates (from point c7 to point i7 in FIG. 7). The refrigerant that flows out of the second heat exchanger 16 flows into the high-pressure refrigerant passage of the internal heat exchanger 17. The refrigerant that flows out of the high-pressure refrigerant passage of the internal heat exchanger 17 flows into the accumulator 20 and is separated into gas and liquid.

[0180] The gas-phase refrigerant separated in the accumulator 20 flows into the low-pressure refrigerant passage of the internal heat exchanger 17. As described above, in the heating mode, the refrigerant flowing into the accumulator 20 flows into the high-pressure refrigerant passage of the internal heat exchanger 17, and the gas-phase refrigerant flowing out from the accumulator 20 flows into the low-pressure refrigerant passage. Therefore, almost no heat exchange occurs in the internal heat exchanger 17 in the heating mode.

[0181] The refrigerant flowing out from the low-pressure refrigerant passage of the internal heat exchanger 17 is drawn into the first compression section 111 and compressed (from point i7 to point a7 in FIG. 7).

[0182] In other words, the heating mode is a second operating mode in which the heat contained in the refrigerant is dissipated to the inside air, which is the object to be heated, in the first heat exchanger 12, and the heat contained in the outside air is absorbed by the refrigerant in the second heat exchanger 16, thereby heating the inside air.

[0183] In addition, in the heating mode, the low-temperature side heat medium circuit 40 cools the battery 70 in the same manner as in the sole cooling mode.

[0184] In addition, in the air distribution unit 50 in the heating mode, the inside air introduced into the second air passage 50b via the second inside / outside air switching device 52b is heated by the first heat exchanger 12. The inside air heated by the first heat exchanger 12 is blown into the vehicle cabin via the interior introducing device 52e as ventilation air to be blown into the vehicle cabin, thereby realizing heating of the vehicle cabin.

[0185] (c) Dehumidifying and Heating Mode The dehumidifying and heating mode is an operating mode in which cooled and dehumidified ventilation air is reheated and blown into the passenger compartment to dehumidify and heat the passenger compartment. The dehumidifying and heating mode is likely to be selected when the auto switch and air conditioner switch are on, the outside air temperature Tam is in the intermediate temperature range (in this embodiment, 10°C or higher and lower than 25°C), or when the target outlet temperature TAO is in the intermediate temperature range.

[0186] The dehumidifying and heating modes include a standalone dehumidifying and heating mode and a cooling and dehumidifying and heating mode. The standalone dehumidifying and heating mode is an operation mode in which the vehicle interior is dehumidified and heated without cooling the battery 70 using the cooling capacity of the refrigeration cycle device 10. The cooling and serial dehumidifying and heating mode is an operation mode in which the battery 70 is cooled using the cooling capacity of the refrigeration cycle device 10 and the vehicle interior is dehumidified and heated.

[0187] (c-1) Single Dehumidifying and Heating Mode In the refrigeration cycle apparatus 10 in the single dehumidifying and heating mode, the control device 60 throttles the heating expansion valve 14a, fully closes the intermediate-pressure expansion valve 14c, throttles the cooling expansion valve 14b, and fully closes the cooling expansion valve 14d. The control device 60 also closes the on-off valve 15e. The control device 60 also causes the first compression section 111 to exert its refrigerant discharge capacity and stops the second compression section 112.

[0188] Therefore, in the refrigeration cycle apparatus 10 in the single dehumidifying and heating mode, as shown by the thick solid line in Figure 8, the refrigerant discharged from the first discharge port 111b of the compressor 11 is switched to a refrigerant circuit of the third operation mode in which the refrigerant circulates in the following order: the first heat exchanger 12, the heating expansion valve 14a, the second heat exchanger 16, the high-pressure refrigerant passage of the internal heat exchanger 17, the cooling expansion valve 14b, the evaporator 18, the accumulator 20, the low-pressure refrigerant passage of the internal heat exchanger 17, and the first suction port 111a of the compressor 11.

[0189] Furthermore, the control device 60 controls the refrigerant discharge capacity of the first compression section 111 in the same manner as in the heating mode.

[0190] In addition, the control device 60 determines the opening pattern of the throttling opening of the heating expansion valve 14a and the throttling opening of the cooling expansion valve 14b based on the target blowing temperature TAO by referring to a control map pre-stored in the control device 60.

[0191] In the control map, as the target outlet temperature TAO increases, the throttle opening of the heating expansion valve 14 a is decreased and the throttle opening of the cooling expansion valve 14 b is increased. Furthermore, the throttle openings of the heating expansion valve 14 a and the cooling expansion valve 14 b are adjusted within a range in which the temperature of the refrigerant flowing into the second heat exchanger 16 is higher than the outside air temperature.

[0192] In the low-temperature side heat medium circuit 40 in the sole dehumidifying and heating mode, the control device 60 controls the operation of each component of the low-temperature side heat medium circuit 40 in the same manner as in the sole cooling mode.

[0193] In the air distribution unit 50 in the single dehumidifying / heating mode, the control device 60 operates a predetermined fan (not shown). In addition, the control device 60 controls the operation of the third inside / outside air switching device 52c in response to an operation signal or the like, as shown in Figure 9, so that outside air or inside air is introduced into the third air passage 50c.

[0194] The control device 60 also controls the operation of the air passage switching device 52d to close the inlet side of the second air passage 50b and open the communication hole 51a. The control device 60 also controls the operation of the interior air introducing device 52e to introduce the blown air that has passed through the first heat exchanger 12 into the vehicle cabin. The control device 60 also controls the operation of other devices to be controlled as appropriate.

[0195] Therefore, in the refrigeration cycle device 10 in the single dehumidifying and heating mode, the state of the refrigerant changes as shown in the Mollier diagram of FIG.

[0196] That is, the refrigerant discharged from the first compression section 111 (point a10 in FIG. 10) flows into the first heat exchanger 12. The refrigerant that flows into the first heat exchanger 12 dissipates heat to the air that has flowed into the second air passage 50b after passing through the evaporator 18, thereby reducing the enthalpy (from point a10 to point b10 in FIG. 10). This heats the air that is blown into the vehicle cabin.

[0197] The refrigerant flowing out of the first heat exchanger 12 is decompressed by the heating expansion valve 14a (from point b10 to point c10 in FIG. 10 ). The refrigerant decompressed by the heating expansion valve 14a flows into the second heat exchanger 16.

[0198] The refrigerant that has flowed into the second heat exchanger 16 dissipates heat to the outside air flowing through the first air passage 50a, thereby decreasing the enthalpy (from point c10 to point d10 in FIG. 10 ). The refrigerant that has flowed out of the second heat exchanger 16 flows into the high-pressure refrigerant passage of the internal heat exchanger 17.

[0199] The refrigerant flowing into the high-pressure refrigerant passage of the internal heat exchanger 17 exchanges heat with the refrigerant flowing through the low-pressure refrigerant passage, thereby reducing its enthalpy (from point d10 to point f10 in FIG. 10). The refrigerant flowing out of the high-pressure refrigerant passage of the internal heat exchanger 17 is decompressed by the cooling expansion valve 14b (from point f10 to point g10 in FIG. 10).

[0200] The refrigerant decompressed by the cooling expansion valve 14b flows into the evaporator 18. The refrigerant that flows into the evaporator 18 evaporates by heat exchange with the outside air or the inside air flowing through the third air passage 50c (from point g10 to point h10 in FIG. 10). This cools the outside air or the inside air passing through the evaporator 18. The refrigerant that flows out of the evaporator 18 flows into the accumulator 20 and is separated into gas and liquid.

[0201] The gas phase refrigerant separated in the accumulator 20 flows into the low-pressure refrigerant passage of the internal heat exchanger 17. The refrigerant that flows into the low-pressure refrigerant passage of the internal heat exchanger 17 exchanges heat with the refrigerant flowing through the high-pressure refrigerant passage, increasing the enthalpy (from point h10 to point i10 in FIG. 10). The refrigerant that flows out of the low-pressure refrigerant passage of the internal heat exchanger 17 is drawn into the first compression section 111 and compressed (from point i10 to point a10 in FIG. 4).

[0202] In the low-temperature side heat medium circuit 40 in the sole dehumidifying and heating mode, the battery 70 is cooled in the same manner as in the sole cooling mode.

[0203] In the air distribution unit 50 in the single dehumidifying / heating mode, the outside air or inside air introduced into the third air passage 50c via the third inside / outside air switching device 52c is cooled and dehumidified by the evaporator 18. The outside air or inside air dehumidified by the evaporator 18 is introduced into the second air passage 50b via the communication hole 51a.

[0204] The outside air or inside air introduced into the second air passage 50b is reheated in the first heat exchanger 12. The outside air or inside air reheated in the first heat exchanger 12 is blown into the vehicle cabin via the interior introducing device 52e as ventilation air to be blown into the vehicle cabin, thereby realizing dehumidifying and heating the vehicle cabin.

[0205] Furthermore, in the refrigeration cycle device 10 in the dehumidifying heating mode, as the target air temperature TAO increases, the throttle opening of the heating expansion valve 14a is decreased and the throttle opening of the cooling expansion valve 14b is increased.

[0206] This allows the amount of heat radiation from the refrigerant in the first heat exchanger 12 to be increased and the amount of heat radiation from the refrigerant in the second heat exchanger to be decreased as the target blow-out temperature TAO increases. Therefore, the heating capacity of the blow-out air in the first heat exchanger 12 can be improved as the target blow-out temperature TAO increases without increasing the rotation speed of the compressor 11.

[0207] (c-2) Cooling, dehumidifying, and heating mode The cooling, dehumidifying, and heating mode is selected when the cooling necessity determination unit determines that it is necessary to cool the battery 70 using the cooling capacity of the refrigeration cycle device 10 while the single dehumidifying and heating mode is being executed.

[0208] In the refrigeration cycle apparatus 10 in the cooling / dehumidifying / heating mode, the control device 60 throttles the heating expansion valve 14a, fully closes the intermediate-pressure expansion valve 14c, throttles the cooling expansion valve 14b, and throttles the cooling expansion valve 14d. The control device 60 also closes the on-off valve 15e. The control device 60 also controls the first compression section 111 to exert its refrigerant discharge capacity and stops the second compression section 112.

[0209] Therefore, in the cooling / dehumidifying / heating mode, the refrigeration cycle apparatus 10 switches to a refrigerant circuit in which the refrigerant circulates in the same way as in the single dehumidifying / heating mode. Furthermore, as shown by the bold dashed line in Fig. 8, the other refrigerant branched at the sixth three-way joint 13f is switched to a refrigerant circuit in which the other refrigerant flows through the cooling expansion valve 14d, the chiller 19, and the eighth three-way joint 13h in this order. In other words, in the cooling / dehumidifying / heating mode, the refrigerant circuit is switched to that of the third operation mode in which the evaporator 18 and the chiller 19 are connected in parallel with respect to the refrigerant flow.

[0210] The control device 60 also controls the throttle opening of the cooling expansion valve 14d so that the throttle opening becomes a predetermined throttle opening for the cooling, dehumidifying, and heating mode. Furthermore, the control device 60 controls the operation of other control target devices in the same way as in the single dehumidifying and heating mode.

[0211] Therefore, in the cooling / dehumidifying / heating mode, the refrigeration cycle apparatus 10 configures a single-stage pressure-boosting refrigeration cycle in which the first heat exchanger 12 and the second heat exchanger 16 function as heat exchangers for heat radiation, and the evaporator 18 and the chiller 19 function as heat exchangers for evaporation. As a result, the first heat exchanger 12 heats the blown air. The evaporator 18 cools the outside air or the inside air. Furthermore, the chiller 19 cools the low-temperature side heat medium.

[0212] In the cooling / dehumidifying / heating mode, the low-temperature side heat medium circuit 40 cools the battery 70 in the same manner as in the cooling / cooling mode.

[0213] In the cooling / dehumidifying / heating mode, the air distribution unit 50, like the single dehumidifying / heating mode, reheats the outside air or inside air cooled and dehumidified by the evaporator 18 in the first heat exchanger 12 and blows it into the passenger compartment, thereby realizing dehumidifying and heating the passenger compartment.

[0214] As described above, the vehicle air conditioner 1 of this embodiment can provide comfortable air conditioning for the vehicle interior and appropriately adjust the temperature of the battery 70, which is an on-board device, by switching the operation mode.

[0215] In a refrigeration cycle apparatus configured to switch refrigerant circuits depending on the operating mode, such as the refrigeration cycle apparatus 10 of this embodiment, the components tend to become larger and heavier, and productivity tends to decrease. This is because the cycle balance differs in each operating mode. More specifically, the pressure resistance and heat resistance of each component must be determined according to the cycle balance in the operating mode that requires high pressure resistance and heat resistance. Therefore, a refrigeration cycle apparatus configured to switch refrigerant circuits tends to increase the size and weight of the components.

[0216] In contrast, the refrigeration cycle device 10 of this embodiment can configure a two-stage compression refrigeration cycle in the first operation mode, in which the refrigerant is compressed in two stages by the first compression section 111 and the second compression section 112. Also, in the second operation mode, it can configure a single-stage compression refrigeration cycle in which the refrigerant is compressed by the first compression section 111. Therefore, an operation mode that provides a more appropriate cycle balance can be selected depending on the application.

[0217] Specifically, in the refrigeration cycle apparatus 10 of this embodiment, the refrigerant pressure in the second heat exchanger 16 in the cooling mode tends to be higher than the refrigerant pressure in the first heat exchanger 12 in the heating mode. Therefore, in the cooling mode, the cycle is more likely to be balanced with a larger pressure difference than in the heating mode. Therefore, the first operating mode is set to the cooling mode, and the second operating mode is set to the heating mode.

[0218] Here, the high-low pressure difference in the cooling mode is the value obtained by subtracting the refrigerant pressure in the evaporator 18 from the refrigerant pressure in the second heat exchanger 16. Also, the high-low pressure difference in the heating mode is the value obtained by subtracting the refrigerant pressure in the second heat exchanger 16 from the refrigerant pressure in the first heat exchanger 12.

[0219] In the refrigeration cycle apparatus 10 of this embodiment, the first heat exchanger 12 is used as a heat exchanger for dissipating heat from the refrigerant in either operation mode. This makes it possible to prevent an increase in the number of heat exchangers even if the refrigerant circuit is configured to be switchable.

[0220] In the refrigeration cycle apparatus 10 of this embodiment, the evaporator 18 is used as a heat exchanger for evaporating the refrigerant. This allows the pressure resistance and heat resistance of the evaporator 18 to be lower than those of the first heat exchanger 12 and the second heat exchanger 16. This prevents the evaporator 18 from becoming larger and heavier.

[0221] Furthermore, in the first operation mode, the refrigerant cooled in the first heat exchanger 12 is drawn into the second compression section 112, thereby suppressing a rise in the temperature of the refrigerant discharged from the second compression section 112. This makes it possible to reduce the heat resistance of the second compression section 112, and to suppress an increase in the size and weight of the second compression section 112.

[0222] As a result, according to the refrigeration cycle apparatus 10 of the present embodiment, even in a refrigeration cycle apparatus configured to be able to switch refrigerant circuits, it is possible to suppress a decrease in productivity.

[0223] The refrigeration cycle device 10 of this embodiment also includes an internal heat exchanger 17. This reduces the enthalpy of the refrigerant flowing into the evaporator 18 in the cooling mode and the dehumidifying heating mode, thereby increasing the refrigeration capacity of the evaporator 18. This improves the COP of the cycle.

[0224] Furthermore, in the cooling mode of the two-stage compression refrigeration cycle, the internal heat exchanger 17 of this embodiment exchanges heat between the high-pressure refrigerant and the low-pressure refrigerant, rather than between the high-pressure refrigerant and the intermediate-pressure refrigerant. Because the low-pressure refrigerant has a lower temperature than the intermediate-pressure refrigerant, the COP of the cycle can be further improved in the cooling mode and the dehumidifying heating mode.

[0225] The refrigeration cycle apparatus 10 of this embodiment also includes a fourth three-way joint 13d as a branching section and an intermediate-pressure expansion valve 14c as a third pressure reducing section, which allows the temperature of the refrigerant drawn into the second compression section 112 to be adjusted in the first operation mode, and allows the second discharge refrigerant temperature Td2 to be set to an appropriate value equal to or lower than the reference temperature KTd2.

[0226] Furthermore, the refrigeration cycle apparatus 10 of this embodiment can switch to a refrigerant circuit for the third operation mode. Therefore, operation in the dehumidifying and heating mode can be performed. In the dehumidifying and heating mode, the air conditioning heat load is generally smaller than in the cooling or heating mode. Therefore, the ability to configure a single-stage vapor compression refrigeration cycle in which the refrigerant is compressed only by the first compression section 111 is effective in reducing the power consumption of the compressor 11.

[0227] In the refrigeration cycle apparatus 10 of this embodiment, the refrigerant discharge capacity of the first compression section 111 is controlled so that the refrigerant drawn into the second compression section 112 is in a supercritical state. This reliably prevents liquid compression in the second compression section 112, thereby protecting the second compression section 112.

[0228] In this embodiment, the second heat exchanger 16 is a heat exchanger having a higher heat exchange capacity than the first heat exchanger 12 and the evaporator 18. As described above, in the vehicle air conditioning system 1 of this embodiment, the refrigerant pressure in the second heat exchanger 16 tends to be higher in the cooling mode than in the heating mode. Therefore, the high heat exchange capacity of the second heat exchanger 16 is effective in protecting the second compression section 112.

[0229] Second Embodiment A vehicle air conditioner 1 of this embodiment includes an air distribution unit 501 shown in FIG. 11 instead of the air distribution unit 50 described in the first embodiment.

[0230] In the air distribution unit 501, a first inside / outside air switching device 52f is disposed at the most upstream part of the air flow of the first air passage 50a relative to the air distribution unit 50. The first inside / outside air switching device 52f switches between introducing inside air and outside air into the first air passage 50a. The operation of the first inside / outside air switching device 52f is controlled by a control signal output from the control device 60.

[0231] In the air distribution unit 501, an outdoor exhaust device 52g is disposed downstream of the evaporator 18 in the third air passage 50c in the air flow direction and upstream of the interior introduction device 52e. The outdoor exhaust device 52g switches the air that has flowed through the third air passage 50c between an air passage that guides the air toward the interior introduction device 52e and an air passage that discharges the air to the outside of the vehicle cabin. The operation of the outdoor exhaust device 52g is controlled by a control signal output from the control device 60.

[0232] In the air distribution unit 501, a second communication hole 51b that communicates the first air passage 50a and the second air passage 50b is formed in the partition wall that separates the first air passage 50a and the second air passage 50b. A second air passage switching device 52h that switches the air passage by opening and closing the second communication hole 51b is disposed in the partition wall that separates the first air passage 50a and the second air passage 50b.

[0233] Specifically, when the second air-passage switching device 52h closes the second communication hole 51b, the first air passage 50a and the second air passage 50b are switched to become independent air passages. Also, when the second air-passage switching device 52h opens the second communication hole 51b, the air that has passed through the second heat exchanger 16 disposed in the first air passage 50a is switched to an air passage that leads, via the second communication hole 51b, to the upstream side of the first heat exchanger 12 disposed in the second air passage 50b.

[0234] In this embodiment, for the sake of clarity, the air-flow path switching device 52d described in the first embodiment will be referred to as a first air-flow path switching device 52d, and the communication hole 51a will be referred to as a first communication hole 51a.

[0235] In the air distribution unit 501, the control device 60 controls the operation of the various switching devices 52b...52h, thereby switching the ventilation channels in the same manner as in the first embodiment. In Fig. 11, the operating states of the various switching devices 52b...52h in the heating mode of this embodiment are indicated by solid lines, and the operating states of the various switching devices 52b...52h in the cooling mode are indicated by two-dot chain lines.

[0236] Other configurations of the air distribution unit 501 and the vehicle air conditioner 1 are similar to those of the air distribution unit 50 and the vehicle air conditioner 1 described in the first embodiment.

[0237] Next, the operation of the vehicle air conditioner 1 of this embodiment configured as described above will be described. The vehicle air conditioner 1 of this embodiment can switch between various operating modes, just like the first embodiment. Furthermore, the vehicle air conditioner 1 of this embodiment can execute (a) a cooling mode and (c) a dehumidifying and heating mode, just like the first embodiment.

[0238] Therefore, the cooling mode (a) of this embodiment is a first operating mode in which heat contained in the refrigerant is dissipated to the outside air in the first heat exchanger 12 and the second heat exchanger 16. Furthermore, the refrigerant absorbs heat contained in the outside air or inside air, which is the object to be cooled, in the evaporator 18, thereby cooling the outside air or inside air. The heating mode (b) of this embodiment will now be described.

[0239] (b) Heating Mode The heating modes in this embodiment include a sole heating mode and a cooling / heating mode. The sole cooling mode is an operation mode in which the vehicle cabin is heated without cooling the battery 70 using the cooling capacity of the refrigeration cycle device 10. The cooling / heating mode is an operation mode in which the battery 70 is cooled using the cooling capacity of the refrigeration cycle device 10 and the vehicle cabin is cooled.

[0240] (b-1) Single Heating Mode In the refrigeration cycle apparatus 10 in the single heating mode, the control device 60 controls the operation of the various control target devices in the same manner as in the single dehumidifying and heating mode of the first embodiment. Therefore, in the refrigeration cycle apparatus 10 in the single heating mode, as shown by the thick solid line in Fig. 8, the refrigeration cycle apparatus 10 is switched to the refrigerant circuit of the third operation mode in which the refrigerant circulates in the same order as in the single dehumidifying and heating mode of the first embodiment.

[0241] In the low-temperature side heat medium circuit 40 in the single heating mode, the control device 60 controls the operation of each component of the low-temperature side heat medium circuit 40 in the same way as in the single dehumidifying and heating mode of the first embodiment.

[0242] In the air distribution unit 501 in the single heating mode, the control device 60 operates a predetermined fan (not shown). The control device 60 also controls the operation of the first inside / outside air switching device 52f so that outside air or inside air is introduced into the first air passage 50a, as shown in Fig. 11. The control device 60 also controls the operation of the third inside / outside air switching device 52c so that outside air is introduced into the third air passage 50b.

[0243] The control device 60 also controls the operation of the first air-passage switching device 52d to close the inlet side of the second air passage 50b and the first communication hole 51a, and controls the operation of the second air-passage switching device 52h to open the second communication passage 51b.

[0244] The control device 60 also controls the operation of the interior intake device 52e so that the blown air that has passed through the first heat exchanger 12 is introduced into the vehicle cabin. The control device 60 also controls the operation of the exterior exhaust device 52g so that the outside air that has passed through the evaporator 18 is exhausted to the outside of the vehicle cabin. The control device 60 also controls the operation of other devices that are subject to control as appropriate.

[0245] Therefore, in the refrigeration cycle apparatus 10 in the single heating mode, the state of the refrigerant changes in the same manner as in the Mollier diagram of Fig. 10 described in the first embodiment. More specifically, in this embodiment, in the process corresponding to point a10 to point b10 in Fig. 10, the refrigerant that has flowed into the first heat exchanger 12 releases heat to the air that has flowed into the second air passage 50b and passed through the second heat exchanger 16, thereby reducing the enthalpy.

[0246] 10, the refrigerant that has flowed into the second heat exchanger 16 releases heat to the outside air or inside air flowing through the first air passage 50a, thereby reducing enthalpy. Also, from point g10 to point h10 in FIG. 10, the refrigerant that has flowed into the evaporator 18 absorbs heat from the outside air flowing through the third air passage 50c and evaporates.

[0247] In other words, the single heating mode is a third operating mode in which the heat of the refrigerant is dissipated to the outside air or inside air, which is the object to be heated, in the first heat exchanger 12 and the second heat exchanger 16, and the heat of the outside air is absorbed by the refrigerant in the evaporator 18, thereby heating the outside air or inside air.

[0248] In the low-temperature side heat medium circuit 40 in the single heating mode, the battery 70 is cooled, similarly to the single dehumidifying and heating mode of the first embodiment.

[0249] In the air distribution unit 501 in the single heating mode, the outside air or inside air introduced into the first air passage 50a via the first inside / outside air switching device 50f is heated in the second heat exchanger 16. The outside air or inside air heated in the second heat exchanger 16 is introduced into the second air passage 50b via the second communication hole 51b.

[0250] The outside air or inside air introduced into the second air passage 50b is further heated in the first heat exchanger 12. The outside air or inside air heated in the first heat exchanger 12 is blown into the vehicle cabin via the interior introducing device 52e as ventilation air to be sent into the vehicle cabin. This achieves heating inside the vehicle cabin. Meanwhile, the outside air introduced into the third air passage 50c absorbs heat as it passes through the evaporator 18 and is discharged outside the vehicle cabin via the exterior exhaust device 52g.

[0251] Furthermore, in the refrigeration cycle device 10 in the single heating mode, the refrigerant heat release temperature in the second heat exchanger 16 is lower than the refrigerant heat release temperature in the first heat exchanger 12. Therefore, in the vehicle air conditioning device 1, the air blown into the vehicle compartment can be efficiently cooled in the order from the second heat exchanger 16 to the first heat exchanger 12.

[0252] (b-2) Cooling and heating mode The cooling and heating mode is selected when the cooling necessity determination unit determines that it is necessary to cool the battery 70 using the cooling capacity of the refrigeration cycle device 10 while the single heating mode is being executed.

[0253] In the refrigeration cycle apparatus 10 in the cooling and heating mode, the control device 60 controls the operation of various control target devices in the same manner as in the cooling, dehumidifying, and heating mode of Embodiment 1. Therefore, in the refrigeration cycle apparatus 10 in the cooling and heating mode, the refrigeration cycle apparatus 10 is switched to the refrigerant circuit of the third operation mode in which the refrigerant circulates in the same order as in the single dehumidifying and heating mode of Embodiment 1, as shown by the thick solid line and the thick dashed line in Figure 8.

[0254] The control device 60 also controls the throttle opening of the cooling expansion valve 14d so that the throttle opening is set to a predetermined value for the cooling / heating mode. Furthermore, the control device 60 controls the operation of other control target devices in the same manner as in the single dehumidifying / heating mode.

[0255] Therefore, in the refrigeration cycle device 10 in the cooling / heating mode, a single-stage pressure-boosting refrigeration cycle is configured in which the first heat exchanger 12 and the second heat exchanger 16 function as heat exchangers for heat dissipation, and the evaporator 18 and chiller 19 function as heat exchangers for evaporation.

[0256] That is, the cooling / heating mode is a third operation mode in which the first heat exchanger 12 and the second heat exchanger 16 radiate heat from the refrigerant to the outside air or the inside air, which is the object to be heated, and the evaporator 18 causes the refrigerant to absorb heat from the outside air, thereby heating the outside air or the inside air. Furthermore, in the cooling / heating mode, the chiller 19 absorbs heat from the low-temperature side heat medium, thereby cooling the low-temperature side heat medium.

[0257] In the cooling / heating mode, the low-temperature side heat medium circuit 40 cools the battery 70 in the same manner as in the cooling / air-conditioning mode described in the first embodiment.

[0258] In the air distribution unit 501 in the single heating mode, the outside air or the inside air heated by the second heat exchanger 16 is further heated by the first heat exchanger 12 and blown into the vehicle compartment, as in the single heating mode. This achieves heating of the vehicle compartment.

[0259] As described above, the vehicle air conditioner 1 of this embodiment can provide comfortable air conditioning for the vehicle interior and appropriately adjust the temperature of the battery 70, which is an on-board device, by switching the operation mode.

[0260] Furthermore, the refrigeration cycle apparatus 10 of this embodiment can achieve the same effects as those of the first embodiment. That is, like the first embodiment, it is possible to prevent an increase in the number of heat exchangers. Also, like the first embodiment, it is possible to prevent an increase in the size and weight of the evaporator 18 and the second compression section 112.

[0261] As a result, according to the refrigeration cycle apparatus 10 of the present embodiment, even in a refrigeration cycle apparatus configured to be able to switch refrigerant circuits, it is possible to suppress a decrease in productivity.

[0262] Third Embodiment In this embodiment, a vehicle air conditioner 1a including a refrigeration cycle device 10a shown in the overall configuration diagram of FIG. 12 will be described.

[0263] In the refrigeration cycle apparatus 10a, the sixth three-way joint 13f and the eighth three-way joint 13h are eliminated from the refrigeration cycle apparatus 10 described in the first embodiment, and a ninth three-way joint 13i, a tenth three-way joint 13j, a first four-way joint 13x, and a second four-way joint 12y are adopted. Furthermore, the refrigeration cycle apparatus 10a has added second to sixth on-off valves 15f to 15j as refrigerant circuit switching units.

[0264] More specifically, in the refrigeration cycle apparatus 10a, one outlet of the first three-way joint 13a is connected to the inlet side of the ninth three-way joint 13i. The other outlet of the first three-way joint 13a is connected to the inlet side of the second on-off valve 15f. The outlet of the second on-off valve 15f is connected to one inlet side of the tenth three-way joint 13i. The outlet of the tenth three-way joint 13j is connected to the inlet side of the heating expansion valve 14a.

[0265] One outlet of the ninth three-way joint 13i is connected to one inlet of the second three-way joint 13b. The other outlet of the ninth three-way joint 13i is connected to the inlet of a third on-off valve 15g. The outlet of the third on-off valve 15g is connected to one inlet of a first four-way joint 13x.

[0266] The first four-way joint 13x is a joint portion having four inlet / outlet ports that communicate with each other. As the first four-way joint 13x, a joint portion formed in the same manner as a three-way joint can be used.

[0267] In the refrigeration cycle apparatus 10a, an inlet side of a fourth on-off valve 15h is connected to one outlet side of the fifth three-way joint 13e. An outlet side of the fourth on-off valve 15h is connected to another inlet side of the first four-way joint 13x. An inlet side of the cooling expansion valve 14b is connected to one outlet side of the first four-way joint 13x. An inlet side of the cooling expansion valve 14d is connected to another outlet side of the first four-way joint 13x.

[0268] In the refrigeration cycle apparatus 10a, one inlet side of the second four-way joint 13y is connected to the outlet of the evaporator 18. Another inlet side of the second four-way joint 13y is connected to the outlet of the refrigerant passage of the chiller 19. The basic configuration of the second four-way joint 13y is similar to that of the first four-way joint 13x.

[0269] One outlet of the second four-way joint 13y is connected to the inlet side of a fifth on-off valve 15i. The outlet of the fifth on-off valve 15i is connected to the other inlet side of the seventh three-way joint 13g. Another outlet of the second four-way joint 13y is connected to the inlet side of a sixth on-off valve 15j. The outlet of the sixth on-off valve 15j is connected to the other inlet side of the tenth three-way joint 13j.

[0270] In the present embodiment, for the sake of clarity, the on-off valve 15 e described in the first embodiment will be referred to as the first on-off valve 15 e. Furthermore, in the refrigeration cycle apparatus 10 a, the second heat exchanger 16 is a first heat absorption / radiation unit, and the evaporator 18 is a second heat absorption / radiation unit.

[0271] In the refrigeration cycle apparatus 10a, the control device 60 controls the operation of the refrigerant circuit switching units 15a...15j, thereby enabling switching to the exact same refrigerant circuit as the refrigeration cycle apparatus 10 described in the first embodiment. Other configurations of the refrigeration cycle apparatus 10a and the vehicle air conditioner 1a are similar to those of the refrigeration cycle apparatus 10 and the vehicle air conditioner 1 described in the first embodiment.

[0272] Next, the operation of the automotive air conditioner 1a of this embodiment configured as described above will be described. The automotive air conditioner 1a can switch between various operating modes, just like the first embodiment. Furthermore, the automotive air conditioner 1a can execute (a) a cooling mode and (c) a dehumidifying and heating mode, just like the first embodiment.

[0273] Therefore, the cooling mode (a) of this embodiment is a first operation mode in which the heat of the refrigerant is radiated to the outside air in the second heat exchanger 16, which is the first heat absorption and radiation unit. Furthermore, the evaporator 18, which is the second heat absorption and radiation unit, causes the refrigerant to absorb heat from the outside air or inside air, which is the object to be cooled, thereby cooling the outside air or inside air. The heating mode (b) of this embodiment will be described below.

[0274] (b) Heating Mode As in the first embodiment, the vehicle air conditioning system 1a does not have an operation mode in which the cooling capacity of the refrigeration cycle system 10a is used to cool the battery 70 and the interior of the vehicle is heated.

[0275] In the refrigeration cycle apparatus 10a in the heating mode, the control device 60 throttles the heating expansion valve 14a, fully closes the intermediate-pressure expansion valve 14c, throttles the cooling expansion valve 14b, and fully closes the cooling expansion valve 14d. The control device 60 also opens the first on-off valve 15e, closes the second on-off valve 15f, opens the third on-off valve 15g, closes the fourth on-off valve 15h, closes the fifth on-off valve 15i, and opens the sixth on-off valve 15j. The control device 60 also controls the first compression section 111 to exert its refrigerant discharge capacity and stops the second compression section 112.

[0276] Therefore, in the refrigeration cycle apparatus 10 in the single dehumidifying and heating mode, as shown by the thick solid line in Figure 12, the refrigerant discharged from the first discharge port 111b of the compressor 11 is switched to a refrigerant circuit of the fourth operation mode in which the refrigerant circulates in this order through the first heat exchanger 12, the cooling expansion valve 14b, the evaporator 18, the heating expansion valve 14a, the second heat exchanger 16, the high-pressure refrigerant passage of the internal heat exchanger 17, the accumulator 20, the low-pressure refrigerant passage of the internal heat exchanger 17, and the first suction port 111a of the compressor 11.

[0277] Further, the control device 60 controls the refrigerant discharge capacity of the first compression section 111, similarly to the first embodiment.

[0278] In addition, the control device 60 determines the opening pattern of the throttling opening of the heating expansion valve 14a and the throttling opening of the cooling expansion valve 14b based on the target blowing temperature TAO by referring to a control map pre-stored in the control device 60.

[0279] In the control map, as the target outlet temperature TAO increases, the throttle opening of the cooling expansion valve 14b is decreased and the throttle opening of the heating expansion valve 14a is increased. Furthermore, the throttle openings of the heating expansion valve 14a and the cooling expansion valve 14b are adjusted within a range in which the temperature of the refrigerant flowing into the evaporator 18 is higher than the outside air temperature.

[0280] In the low-temperature side heat medium circuit 40 in the heating mode, the control device 60 controls the operation of each component of the low-temperature side heat medium circuit 40 in the same manner as in the first embodiment.

[0281] In the air distribution unit 50 in the heating mode, the control device 60 controls the operation of the various switching devices 52b...52e so that air flows, similar to the dehumidifying heating mode of the first embodiment.

[0282] Therefore, in the refrigeration cycle device 10a in the heating mode, the state of the refrigerant changes as shown in the Mollier diagram of FIG.

[0283] That is, the refrigerant discharged from the first compression section 111 (point a13 in FIG. 13) flows into the first heat exchanger 12. The refrigerant that flows into the first heat exchanger 12 dissipates heat to the air that has flowed into the second air passage 50b after passing through the evaporator 18, thereby reducing the enthalpy (from point a13 to point b13 in FIG. 13). This heats the air that is blown into the vehicle cabin.

[0284] The refrigerant flowing out of the first heat exchanger 12 is decompressed by the cooling expansion valve 14b (from point b13 to point g13 in FIG. 13 ). The refrigerant decompressed by the cooling expansion valve 14b flows into the evaporator 18, which is the second heat absorption and radiation part.

[0285] The refrigerant that flows into the evaporator 18 releases heat to the outside air or the inside air flowing through the third air passage 50c, thereby reducing the enthalpy (from point g13 to point h13 in FIG. 13 ), thereby heating the air that flows into the first heat exchanger 12. The refrigerant that flows out of the evaporator 18 is decompressed by the heating expansion valve 14a (from point h13 to point c13 in FIG. 13 ).

[0286] The refrigerant decompressed by the heating expansion valve 14a flows into the second heat exchanger 16. The refrigerant that flows into the second heat exchanger 16 absorbs heat from the outside air flowing through the first air passage 50a and evaporates (from point c13 to point i13 in FIG. 13). The refrigerant that flows out of the second heat exchanger 16 flows into the high-pressure refrigerant passage of the internal heat exchanger 17. The refrigerant that flows out of the high-pressure refrigerant passage of the internal heat exchanger 17 flows into the accumulator 20 and is separated into gas and liquid.

[0287] The gas-phase refrigerant separated in the accumulator 20 flows into the low-pressure refrigerant passage of the internal heat exchanger 17. As described above, in the heating mode, the refrigerant flowing into the accumulator 20 flows into the high-pressure refrigerant passage of the internal heat exchanger 17, and the gas-phase refrigerant flowing out from the accumulator 20 flows into the low-pressure refrigerant passage. Therefore, in the heating mode of the internal heat exchanger 17 of this embodiment, almost no heat exchange occurs.

[0288] The refrigerant flowing out from the low-pressure refrigerant passage of the internal heat exchanger 17 is drawn into the first compression section 111 and compressed (from point i13 to point a13 in FIG. 13).

[0289] In other words, the heating mode is a fourth operating mode in which the heat of the refrigerant is dissipated to the outside air or inside air, which is the object to be heated, in the first heat exchanger 12 and the evaporator 18, and the heat of the outside air is absorbed by the refrigerant in the second heat exchanger 16, thereby heating the outside air or inside air.

[0290] In addition, in the heating mode, the low-temperature side heat medium circuit 40 cools the battery 70 in the same manner as in the first embodiment.

[0291] In the air distribution unit 50 in the heating mode, the outside air or the inside air heated by the evaporator 18 is further heated by the first heat exchanger 12 and blown into the vehicle compartment, thereby realizing heating of the vehicle compartment.

[0292] As described above, the vehicle air conditioner 1a of this embodiment can provide comfortable air conditioning for the vehicle interior and appropriately adjust the temperature of the battery 70, which is an on-board device, by switching the operation mode.

[0293] Furthermore, the refrigeration cycle apparatus 10a of this embodiment can achieve the same effects as those of the first embodiment. That is, like the first embodiment, an increase in the number of heat exchangers can be suppressed. Also, like the first embodiment, an increase in the size and weight of the second compression section 112 can be suppressed.

[0294] As a result, according to the refrigeration cycle apparatus 10a of this embodiment, even in a refrigeration cycle apparatus configured to be able to switch refrigerant circuits, it is possible to suppress a decrease in productivity.

[0295] In the refrigeration cycle device 10a in the heating mode, the refrigerant heat radiation temperature in the first heat exchanger 12 is higher than the refrigerant heat radiation temperature in the evaporator 18. Therefore, in the vehicle air conditioning device 1a, the air to be blown into the vehicle compartment can be efficiently heated in the order from the evaporator 18 to the first heat exchanger 12.

[0296] Fourth Embodiment In this embodiment, an example will be described in which a refrigeration cycle device 10b is applied to a vehicle air conditioner 1b. Unlike the vehicle air conditioner 1 described in the first embodiment, the vehicle air conditioner 1b does not have a function of adjusting the temperature of on-board equipment. The vehicle air conditioner 1b includes a refrigeration cycle device 10b, a low-temperature side heat medium circuit 40a, an air distribution unit 50, a control device 60, etc.

[0297] As shown in the overall configuration diagram of Figure 14, the refrigeration cycle device 10b does not include the first three-way joint 13a, the third three-way joint 13c, the fifth three-way joint 13e, the seventh three-way joint 13g, the heating expansion valve 14a, and the opening / closing valve 15e, as compared to the refrigeration cycle device 10 described in the first embodiment.

[0298] Therefore, one inlet of the second three-way joint 13b is connected to the refrigerant outlet of the first heat exchanger 12. The refrigerant inlet of the second heat exchanger 16a is connected to the second discharge port 112b. The second heat exchanger 16a has a configuration equivalent to that of the second heat exchanger 16 described in the first embodiment. In the refrigeration cycle apparatus 10b, the inlet of the accumulator 20 is connected to the outlet of the eighth three-way joint 13h.

[0299] The refrigeration cycle apparatus 10b employs an intermediate-pressure internal heat exchanger 17a instead of the internal heat exchanger 17. The intermediate-pressure internal heat exchanger 17a has a high-pressure refrigerant passage and an intermediate-pressure refrigerant passage, and exchanges heat between the high-pressure refrigerant flowing through the high-pressure refrigerant passage and the intermediate-pressure refrigerant flowing through the intermediate-pressure refrigerant passage. The other refrigerant branched at the fourth three-way joint 13d flows through the high-pressure refrigerant passage. The intermediate-pressure refrigerant is reduced in pressure by the intermediate-pressure expansion valve 14c.

[0300] The outlet of the high-pressure refrigerant passage of the intermediate-pressure internal heat exchanger 17a is connected to the inlet side of the sixth three-way joint 13f. The outlet of the intermediate-pressure refrigerant passage of the intermediate-pressure internal heat exchanger 17a is connected to the other inlet side of the second three-way joint 13b.

[0301] In the refrigeration cycle apparatus 10b, the first heat exchanger 12 is a first heat radiating section, the second heat exchanger 16a is a second heat radiating section, the evaporator 18 is a first heat absorbing section, the chiller 19 is a second heat absorbing section, and the cooling expansion valve 14d is a fourth expansion valve.

[0302] As shown in the overall configuration diagram of FIG. 14 , the low-temperature side heat medium circuit 40 a does not have the coolant passage 70 a of the battery 70, the low-temperature side three-way valve 42, and the heat medium three-way joint 43, as compared to the low-temperature side heat medium circuit 40 described in the first embodiment.

[0303] The second refrigerant sensor 62e connected to the control device 60 of this embodiment detects the temperature of the refrigerant at the outlet side of the high-pressure refrigerant passage of the intermediate-pressure internal heat exchanger 17a as a second refrigerant temperature Ti2 and detects the pressure of the second refrigerant as a second refrigerant pressure Pi2. The rest of the configuration of the automotive air conditioner 1b is the same as that of the automotive air conditioner 1 described in the first embodiment.

[0304] Next, the operation of the vehicle air conditioner 1b of this embodiment with the above configuration will be described. As in the first embodiment, the vehicle air conditioner 1b of this embodiment can also switch between various operating modes. Each operating mode will be described below.

[0305] In the refrigeration cycle apparatus 10b in the cooling-only mode, the control device 60 controls the intermediate-pressure expansion valve 14c to be throttled or fully closed, the cooling expansion valve 14b to be throttled, and the cooling expansion valve 14d to be fully closed. The control device 60 also controls both the first compression section 111 and the second compression section 112 to exert their refrigerant discharge capacities.

[0306] 11 , the refrigeration cycle apparatus 10b in the cooling mode is switched to a refrigerant circuit for a first operating mode in which the refrigerant discharged from the first discharge port 111b of the compressor 11 circulates in this order through the first heat exchanger 12 and the second suction port 112a of the compressor 11. Furthermore, the refrigerant discharged from the second discharge port 112b of the compressor 11 circulates in this order through the second heat exchanger 16a, the intermediate-pressure expansion valve 14c, the intermediate-pressure refrigerant passage of the intermediate-pressure internal heat exchanger 17a, and the second suction port 112a of the compressor 11, and the refrigerant discharged from the second discharge port 112b of the compressor 11 circulates in this order through the second heat exchanger 16a, the high-pressure refrigerant passage of the intermediate-pressure internal heat exchanger 17a, the cooling expansion valve 14b, the evaporator 18 serving as the first heat absorption unit, the accumulator 20, and the first suction port 111a of the compressor 11.

[0307] Furthermore, the control device 60 controls the operation of the control target devices of the refrigeration cycle device 10b in the same manner as in the cooling mode of the first embodiment.

[0308] In the low-temperature side heat medium circuit 40a in the cooling mode, the control device 60 stops the low-temperature side pump 41. In the air distribution unit 50 in the cooling mode, the control device 60 controls the operation of the controlled devices of the air distribution unit 50, similar to the cooling mode of the first embodiment.

[0309] Therefore, in the refrigeration cycle device 10b in the cooling mode, the state of the refrigerant changes as shown in the Mollier diagram of FIG.

[0310] That is, the refrigerant discharged from the first compression section 111 (point a15 in FIG. 15 ) flows into the first heat exchanger 12. The refrigerant that flows into the first heat exchanger 12 dissipates heat to the outside air flowing through the second air passage 50b, thereby reducing enthalpy. The refrigerant that flows out of the first heat exchanger 12 merges with the refrigerant that flows out of the intermediate-pressure refrigerant passage of the intermediate-pressure internal heat exchanger 17a (point k15 in FIG. 15 ), and is drawn into the second compression section 112 and compressed (from point j15 to point c15 in FIG. 15 ).

[0311] The refrigerant discharged from the second compression section 112 (point c15 in FIG. 15) flows into the second heat exchanger 16a. The refrigerant that flows into the second heat exchanger 16a dissipates heat to the outside air flowing through the first air passage 50a, thereby reducing its enthalpy (from point c15 to point d15 in FIG. 15). The flow of the refrigerant that flows out of the second heat exchanger 16a is branched at the fourth three-way joint 13d.

[0312] One of the refrigerant branches at the fourth three-way joint 13d is decompressed by the intermediate-pressure expansion valve 14c (from point d15 to point e15 in FIG. 15 ), and flows into the intermediate-pressure refrigerant passage of the intermediate-pressure internal heat exchanger 17a.

[0313] The refrigerant flowing into the intermediate-pressure refrigerant passage of the intermediate-pressure internal heat exchanger 17a exchanges heat with the refrigerant flowing through the high-pressure refrigerant passage, increasing its enthalpy (from point e15 to point k15 in FIG. 15 ). The refrigerant flowing out of the intermediate-pressure refrigerant passage of the intermediate-pressure internal heat exchanger 17a joins with the refrigerant flowing out of the first heat exchanger 12, and is drawn into the second compression section 112.

[0314] However, when the intermediate pressure expansion valve 14c is fully closed, the refrigerant flow is not branched at the fourth three-way joint 3d, i.e., the state of the refrigerant does not change from point d15 to point e15, from point e15 to point k15, or from point k15 to point j15 in Figure 15.

[0315] The other refrigerant branched at the fourth three-way joint 13d flows into the high-pressure refrigerant passage of the intermediate-pressure internal heat exchanger 17a. The refrigerant flowing into the high-pressure refrigerant passage of the intermediate-pressure internal heat exchanger 17a exchanges heat with the refrigerant flowing through the intermediate-pressure refrigerant passage, thereby reducing its enthalpy (from point d15 to point m15 in FIG. 15). The refrigerant flowing out of the high-pressure refrigerant passage of the intermediate-pressure internal heat exchanger 17a is decompressed by the cooling expansion valve 14b (from point m15 to point g15 in FIG. 15).

[0316] The refrigerant decompressed by the cooling expansion valve 14b flows into the evaporator 18. The refrigerant that has flowed into the evaporator 18 evaporates by heat exchange with the outside air or the inside air flowing through the third air passage 50c (from point g15 to point i15 in FIG. 15). As a result, the outside air or the inside air passing through the evaporator 18 is cooled.

[0317] The refrigerant flowing out from the evaporator 18 flows into the accumulator 20 and is separated into gas and liquid. The gas phase refrigerant separated in the accumulator 20 is drawn into the first compression section 111 and compressed (from point i15 to point a15 in FIG. 15).

[0318] In other words, the cooling mode is a first operating mode in which the heat contained in the refrigerant is dissipated to the outside air in the first heat exchanger 12 and the second heat exchanger 16a, and the heat contained in the outside air or inside air, which is the object to be cooled, is absorbed by the refrigerant in the evaporator 18, thereby cooling the outside air or inside air.

[0319] In the air distribution unit 50 in the cooling mode, the outside air or the inside air cooled by the evaporator 18 is blown into the vehicle compartment as ventilation air, as in the first embodiment, thereby realizing cooling of the vehicle compartment.

[0320] In the refrigeration cycle apparatus 10b in the heating mode, the control device 60 controls the intermediate-pressure expansion valve 14c to be throttled or fully closed, the cooling expansion valve 14b to be fully closed, and the cooling expansion valve 14d to be throttled. The control device 60 also controls both the first compression section 111 and the second compression section 112 to exhibit their refrigerant discharge capacities.

[0321] Therefore, in the refrigeration cycle apparatus 10b in the heating mode, the refrigerant discharged from the first discharge port 111b of the compressor 11 circulates in this order through the first heat exchanger 12 and the second suction port 112a of the compressor 11. Furthermore, the refrigerant discharged from the second discharge port 112b of the compressor 11 circulates in this order through the second heat exchanger 16a, the intermediate-pressure expansion valve 14c, the intermediate-pressure refrigerant passage of the intermediate-pressure internal heat exchanger 17a, and the second suction port 112a of the compressor 11, and as shown by the thick dashed line in Fig. 14 , the system is switched to a refrigerant circuit for a fifth operation mode in which the refrigerant discharged from the second discharge port 112b of the compressor 11 circulates in this order through the second heat exchanger 16a, the high-pressure refrigerant passage of the intermediate-pressure internal heat exchanger 17a, the cooling expansion valve 14d, the chiller 19 serving as the second heat absorption unit, the accumulator 20, and the first suction port 111a of the compressor 11.

[0322] The control device 60 also controls the throttle opening of the cooling expansion valve 14 d so that the second refrigerant pressure Pi2 approaches the target high pressure PDO2. Similarly to the cooling mode, the control device 60 also controls the operation of other control target devices of the refrigeration cycle device 10 b.

[0323] In the low-temperature side heat medium circuit 40a in the heating mode, the control device 60 operates the low-temperature side pump 41 so as to exert a predetermined reference pumping capacity. In the air distribution unit 50 in the heating mode, the control device 60 controls the operation of the controlled devices of the air distribution unit 50, as in the heating mode of the first embodiment.

[0324] Therefore, in the refrigeration cycle apparatus 10b in the heating mode, as in the cooling mode, the refrigerant discharged from the first compression section 111 dissipates heat in the first heat exchanger 12. This heats the air blown into the vehicle cabin. Also, the refrigerant discharged from the second compression section 112 dissipates heat in the second heat exchanger 16a. Furthermore, in the refrigeration cycle apparatus 10b in the heating mode, as shown by the thick dashed line in Fig. 14 , the refrigerant decompressed by the cooling expansion valve 14d absorbs heat from the low-temperature side heat medium in the chiller 19 and evaporates.

[0325] In other words, the heating mode is a fifth operating mode in which the heat contained in the refrigerant is dissipated to the inside air, which is the object to be heated, in the first heat exchanger 12, and the heat contained in the outside air, which is the object to be cooled, is absorbed by the refrigerant in the chiller 19, thereby heating the inside air.

[0326] In the low-temperature side heat medium circuit 40 in the heating mode, the low-temperature side heat medium pumped from the low-temperature side pump 41 flows into the heat medium passage of the chiller 19. The low-temperature side heat medium that has flowed into the heat medium passage of the chiller 19 absorbs heat from the refrigerant and is cooled. In the low-temperature side radiator 44, the low-temperature side heat medium absorbs heat from the outside air.

[0327] The low-temperature side heat medium that flows out of the heat medium passage of the chiller 19 flows into the low-temperature side radiator 44. In the low-temperature side radiator 44, the low-temperature side heat medium absorbs heat from the outside air. The low-temperature side heat medium that flows out of the low-temperature side radiator 44 is sucked into the low-temperature side pump 41 and pumped to the heat medium passage side of the chiller 19.

[0328] In the air distribution unit 50 in the heating mode, the inside air heated by the first heat exchanger 12 is blown into the vehicle compartment, as in the first embodiment, thereby realizing heating of the vehicle compartment.

[0329] In the refrigeration cycle device 10b in the dehumidifying and heating mode, the control device 60 controls the intermediate-pressure expansion valve 14c to be throttled or fully closed, the cooling expansion valve 14b to be throttled, and the cooling expansion valve 14d to be throttled. The control device 60 also controls both the first compression section 111 and the second compression section 112 to exhibit their refrigerant discharge capacities.

[0330] Therefore, in the dehumidifying and heating mode, the refrigeration cycle apparatus 10b switches to a refrigerant circuit in which the refrigerant circulates in the same manner as in the cooling mode, as shown by the thick solid line in Fig. 14. Furthermore, as shown by the thick dashed line in Fig. 14, the other refrigerant branched at the sixth three-way joint 13f is switched to a refrigerant circuit in which the other refrigerant flows through the cooling expansion valve 14d, the chiller 19, and the eighth three-way joint 13h in this order. In other words, in the dehumidifying and heating mode, the refrigerant circuit switches to one in which the evaporator 18 and the chiller 19 are connected in parallel with respect to the refrigerant flow.

[0331] The control device 60 also controls the throttle opening of the cooling expansion valve 14b so that the second refrigerant pressure Pi2 approaches the target high pressure PDO2. The control device 60 also controls the throttle opening of the cooling expansion valve 14d so that the throttle opening becomes a predetermined throttle opening for the cooling / air-conditioning mode. The control device 60 also controls the operation of other control target devices of the refrigeration cycle device 10b, similar to the cooling mode.

[0332] In the low-temperature side heat medium circuit 40a in the dehumidifying and heating mode, the control device 60 operates the low-temperature side pump 41 to achieve a predetermined reference pumping capacity. In the air distribution unit 50 in the dehumidifying and heating mode, the control device 60 controls the operation of the controlled devices of the air distribution unit 50, as in the dehumidifying and heating mode of the first embodiment.

[0333] Therefore, in the refrigeration cycle apparatus 10b in the dehumidifying and heating mode, as in the cooling mode, the refrigerant discharged from the first compression section 111 dissipates heat in the first heat exchanger 12. This heats the blown air that has passed through the evaporator 18. In addition, the refrigerant discharged from the second compression section 112 dissipates heat in the second heat exchanger 16a.

[0334] Furthermore, in the refrigeration cycle apparatus 10b in the dehumidifying heating mode, as in the cooling mode, one of the refrigerants branched at the sixth three-way joint 13f absorbs heat from the outside air or the inside air and evaporates in the evaporator 18. As in the heating mode, the other refrigerant branched at the sixth three-way joint 13f absorbs heat from the low-temperature side heat medium and evaporates in the chiller 19.

[0335] In the dehumidifying heating mode, in the low-temperature side heat medium circuit 40, the low-temperature side heat medium that has flowed into the heat medium passage of the chiller 19 is cooled by absorbing heat from the refrigerant, as in the heating mode. In the low-temperature side radiator 44, the low-temperature side heat medium absorbs heat from the outside air.

[0336] In the air distribution unit 50 in the dehumidifying and heating mode, the outside air or the inside air that has been cooled and dehumidified by the evaporator 18 is reheated by the first heat exchanger 12 and blown into the vehicle compartment, as in the first embodiment. This achieves dehumidifying and heating the vehicle compartment.

[0337] As described above, the vehicle air conditioner 1b of this embodiment can provide comfortable air conditioning for the vehicle interior by switching the operation mode.

[0338] Furthermore, the refrigeration cycle apparatus 10b of this embodiment can select the evaporator 18 and chiller 19 with different heat exchange capacities (in other words, heat absorption performance) as heat exchange units for causing the refrigerant to absorb heat depending on the operation mode. Therefore, it is possible to select an operation mode that provides a more appropriate cycle balance depending on the application.

[0339] In the refrigeration cycle apparatus 10b of this embodiment, the first heat exchanger 12 and the second heat exchanger 16a are used as heat exchangers for dissipating heat from the refrigerant in both operation modes, which prevents the number of heat exchangers from increasing even if the refrigerant circuit is configured to be switchable.

[0340] In the refrigeration cycle apparatus 10b of this embodiment, the evaporator 18 and the chiller 19 are used as heat exchangers for evaporating the refrigerant in both operation modes. This allows the pressure resistance and heat resistance of the evaporator 18 and the chiller 19 to be lower than those of the first heat exchanger 12 and the second heat exchanger 16a. This prevents the evaporator 18 and the chiller 19 from becoming larger and heavier.

[0341] Furthermore, in the refrigeration cycle apparatus 10b of this embodiment, in any operation mode, the refrigerant cooled in the first heat exchanger 12 is drawn into the second compression section 112, thereby suppressing a temperature rise in the refrigerant discharged from the second compression section 112. This makes it possible to reduce the pressure resistance and heat resistance of the second compression section 112, and suppress an increase in the size and weight of the second compression section 112.

[0342] As a result, the refrigeration cycle apparatus 10b of this embodiment can achieve the same effects as those of the first embodiment. That is, even in a refrigeration cycle apparatus configured to be able to switch refrigerant circuits, it is possible to suppress a decrease in productivity.

[0343] The present disclosure is not limited to the above-described embodiments, and various modifications can be made as follows within the scope of the present disclosure.

[0344] In the above embodiment, an example has been described in which the refrigeration cycle device according to the present disclosure is applied to a vehicle air conditioner, but the application of the refrigeration cycle device according to the present disclosure is not limited to this. The refrigeration cycle device may also be applied to a stationary air conditioner, etc. For example, the refrigeration cycle device may be applied to an air conditioner with a server temperature adjustment function that cools a computer that functions as a server and also conditions the air in a room in which the server is housed.

[0345] In the above embodiment, the battery 70 is used as the in-vehicle device to be temperature-controlled, but the in-vehicle device is not limited to this. For example, the in-vehicle device may be a motor generator, an inverter, a sensor processing unit, a transaxle, an ADAS control device, or other device that generates a relatively large amount of heat during operation.

[0346] A motor generator is an electric motor that functions as both a motor that outputs driving force for driving and a generator. An inverter is an electric circuit device that supplies power to the motor generator, etc. A sensor processing unit is a control device that integrates environmental sensor interfaces and communication functions for autonomous driving and energy-saving driving. A transaxle is a power transmission mechanism that integrates a transmission, differential gear, etc. An ADAS control device is a control device for an advanced driver assistance system.

[0347] In the first embodiment described above, the first operation mode is the cooling mode and the second operation mode is the heating mode, but the present invention is not limited to this.

[0348] That is, in the first embodiment, the first operation mode may be an operation mode in which the heat of the refrigerant is radiated to the object to be heated by the heat radiating unit and the heat absorbing unit, and the heat of the outside air is absorbed by the refrigerant by the heat absorbing unit, thereby heating the object to be heated. Furthermore, the second operation mode may be an operation mode in which the heat of the refrigerant is radiated to the outside air by the heat radiating unit, and the heat of the object to be cooled is absorbed by the refrigerant by the heat absorbing unit, thereby cooling the object to be cooled.

[0349] In the second embodiment described above, the first operation mode is the cooling mode and the third operation mode is the heating mode, but the present invention is not limited to this.

[0350] That is, in the second embodiment, the first operating mode may be an operating mode in which the heat of the refrigerant is radiated to the object to be heated by the heat radiating unit and the heat absorbing unit, and the heat of the outside air is absorbed by the refrigerant by the heat absorbing unit, thereby heating the object to be heated. Furthermore, the second operating mode may be an operating mode in which the heat of the refrigerant is radiated to the outside air by at least one of the heat radiating unit and the heat absorbing unit, and the heat of the object to be cooled is absorbed by the refrigerant by the heat absorbing unit, thereby cooling the object to be cooled.

[0351] In the third embodiment described above, the first operation mode is the cooling mode and the fourth operation mode is the heating mode, but the present invention is not limited to this.

[0352] That is, in the third embodiment, the first operating mode may be an operating mode in which the first heat absorption and radiation unit radiates heat from the refrigerant to the object to be heated, and the second heat absorption and radiation unit absorbs heat from the outside air into the refrigerant, thereby heating the object to be heated.Furthermore, the fourth operating mode may be an operating mode in which the first heat absorption and radiation unit and the second heat absorption and radiation unit radiate heat from the refrigerant to the outside air, and the first heat absorption and radiation unit absorbs heat from the object to be cooled, thereby cooling the object to be cooled.

[0353] In the fourth embodiment described above, the first operation mode is the cooling mode and the fifth operation mode is the heating mode, but the present invention is not limited to this.

[0354] That is, the first operating mode may be an operating mode in which the second heat radiating section radiates heat from the refrigerant to the object to be heated, and the first heat absorbing section absorbs heat from the outside air into the refrigerant, thereby heating the object to be heated.Furthermore, the fifth operating mode may be an operating mode in which the first heat radiating section radiates heat from the refrigerant to the outside air, and the second heat absorbing section absorbs heat from the object to be cooled, thereby cooling the object to be cooled.

[0355] The configuration of the refrigeration cycle device according to the present disclosure is not limited to the configuration disclosed in the above-described embodiment.

[0356] For example, the configuration of the refrigeration cycle apparatus according to the present disclosure may be appropriately integrated or separated to improve productivity of the refrigeration cycle apparatus. For example, in the first embodiment, a four-way joint in which the fifth three-way joint 13 e and the sixth three-way joint 13 f are integrated may be employed.

[0357] For example, in the above-described embodiment of the refrigeration cycle device 10, 10a, an example was described in which a composite compressor was used as the compressor 11, but in order to improve mountability, different compressors may be used as the first compression section 111 and the second compression section 112.

[0358] Furthermore, the compressor 11 may be configured so that both the compression mechanism of the first compression section 111 and the compression mechanism of the second compression section 112 can be rotationally driven by the same electric motor. In this case, in the refrigeration cycle device 10 of the first embodiment, it is desirable that the electric motor be configured so that either one of the compression mechanisms can be rotationally driven by a clutch mechanism or the like.

[0359] In the refrigeration cycle apparatus 10, 10a of the above-described embodiment, the first heat exchanger 12 is a heat exchanger that exchanges heat between a refrigerant and air. However, the refrigerant may be exchanged with air via a heat medium, as in the chiller 19. That is, a heat medium circulation circuit including a water-refrigerant heat exchanger and an air-heat medium heat exchanger may be used instead of the first heat exchanger 12. The same applies to the second heat exchangers 16, 16a and the evaporator 18.

[0360] Furthermore, in the above-described embodiment, an example was described in which the heat exchange capacity (i.e., heat absorption performance) of the evaporator 18 is higher than the heat exchange capacity of the chiller 19, but the heat exchange capacity of the chiller 19 may also be higher than the heat exchange capacity of the evaporator 18 depending on the cycle balance.

[0361] Furthermore, the group of control sensors connected to the input side of the control device 60 is not limited to the detection units disclosed in the above embodiment. Various detection units may be added as needed.

[0362] In the above-described embodiment, the refrigeration cycle apparatus 10, 10a, and 10b employ carbon dioxide as a refrigerant to configure a supercritical cycle, but the present invention is not limited to this. For example, a subcritical refrigeration cycle may employ R134a, R600a, R410A, R404A, R32, R407C, R290, or a mixture of these refrigerants, in which the high-pressure refrigerant does not exceed the critical pressure of the refrigerant.

[0363] When configuring a subcritical refrigeration cycle, it is desirable to have the refrigerant in a gas phase state when drawn into the second compression section 112. Of course, even when configuring a supercritical refrigeration cycle, if the refrigerant in the second compression section 112 is in a gas phase when drawn into the second compression section 112, liquid compression in the second compression section 112 can be avoided.

[0364] In the above embodiment, an example in which an ethylene glycol aqueous solution is used as the low-temperature heat medium is described, but the present invention is not limited to this. For example, a solution containing dimethylpolysiloxane or nanofluid, antifreeze, a water-based liquid refrigerant containing alcohol, or a liquid medium containing oil may be used.

[0365] The control aspects of the refrigeration cycle device according to the present disclosure are not limited to the control aspects disclosed in the above-described embodiments.

[0366] For example, in the refrigeration cycle apparatus 10 of the first embodiment, the effects of the refrigeration cycle apparatus according to the present disclosure can be obtained as long as the refrigeration cycle apparatus 10 is capable of switching at least between the first and second operating modes. That is, even in a refrigeration cycle apparatus configured to be able to switch the refrigerant circuit, a decrease in productivity can be suppressed.

[0367] Similarly, the refrigeration cycle apparatus 10 of the second embodiment can achieve the effects of the refrigeration cycle apparatus according to the present disclosure as long as it is switchable between at least the first and third operating modes. The refrigeration cycle apparatus 10a of the third embodiment can achieve the effects of the refrigeration cycle apparatus according to the present disclosure as long as it is switchable between at least the first and fourth operating modes. The refrigeration cycle apparatus 10a of the fourth embodiment can achieve the effects of the refrigeration cycle apparatus according to the present disclosure as long as it is switchable between at least the first and fifth operating modes.

[0368] The refrigeration cycle devices 10, 10a, and 10b may also be capable of operating in other modes. For example, the vehicle air conditioner 1, 1a may be capable of operating in a single cooling mode in which the vehicle-mounted devices are cooled without air-conditioning the vehicle interior.

[0369] Specifically, in the single-cooling mode of the refrigeration cycle apparatus 10 of the first embodiment, the heating expansion valve 14a is fully closed, the intermediate-pressure expansion valve 14c is throttled or fully closed, the cooling expansion valve 14b is fully closed, and the cooling expansion valve 14d is throttled. The control device 60 also closes the on-off valve 15e. The control device 60 may also cause both the first compression section 111 and the second compression section 112 to exert their refrigerant discharge capacities.

[0370] Furthermore, the internal heat exchanger 17 may be eliminated from the refrigeration cycle devices 10 and 10a. For example, the internal heat exchanger 17 may be eliminated from the vehicle air conditioning device 1 of the first embodiment, and the cooling / heating mode may be implemented. Specifically, in the cooling / heating mode, the on-off valve 15e may be closed and the cooling expansion valve 14d may be throttled, as compared with the heating mode. This allows the chiller 19 to cool the low-temperature side heat medium.

[0371] For example, in the vehicle air conditioning system 1 of the first embodiment, the internal heat exchanger 17 may be eliminated, and the throttle openings of the heating expansion valve 14 a and the cooling expansion valve 14 b may be adjusted so that the temperature of the refrigerant flowing into the second heat exchanger 16 is lower than the outside air temperature during the dehumidifying and heating mode. In this case, the second heat exchanger 16 functions as an evaporative heat exchanger that evaporates the refrigerant.

[0372] For example, in the vehicle air conditioning system 1 of the second embodiment, the internal heat exchanger 17 may be eliminated, and the openings of the heating expansion valve 14 a and the cooling expansion valve 14 b may be adjusted so that the temperature of the refrigerant flowing into the second heat exchanger 16 is lower than the outside air temperature during the heating mode. In this case, the third operating mode becomes an operating mode in which the blown air is heated only by the first heat exchanger 12, which is a heat radiating part.

[0373] The means disclosed in each of the above embodiments may be combined as appropriate within a practicable range. For example, the low-temperature side heat medium circuit 40 described in the first embodiment may be adopted in the refrigeration cycle device 10b of the fourth embodiment so as to be able to cool on-vehicle equipment.

[0374] Furthermore, a second heating mode that operates in the same manner as in the first embodiment may be added to the vehicle air conditioner 1 of the second embodiment. Similarly, a second heating mode that operates in the same manner as in the first embodiment may be added to the vehicle air conditioner 1a of the third embodiment.

[0375] The features of the refrigeration cycle device disclosed in this specification are as follows: (Item 1) A refrigeration cycle device includes a first compression section (111) that compresses and discharges a refrigerant, a heat dissipation section (12) that dissipates heat from the refrigerant discharged from the first compression section, a first pressure reduction section (14a) that depressurizes the refrigerant, a second compression section (112) that compresses and discharges the refrigerant, a heat absorption and dissipation section (16) that absorbs or dissipates heat from the refrigerant, a second pressure reduction section (14b) that depressurizes the refrigerant, a heat absorption section (18) that absorbs heat into the refrigerant depressurized in the second pressure reduction section, and a refrigerant circuit switching section (15a...15e) that switches a refrigerant circuit through which the refrigerant is circulated, In a first operation mode, the refrigerant circuit switching unit switches to a refrigerant circuit that causes the refrigerant flowing out of the heat radiating unit to be sucked into the second compression unit, causes the refrigerant discharged from the second compression unit to flow into the heat absorbing and radiating unit, depressurizes the refrigerant that has radiated heat in the heat absorbing and radiating unit in the second decompression unit, and sucks the refrigerant flowing out of the heat absorbing unit into the first compression unit; and in a second operation mode, the refrigerant circuit switching unit switches to a refrigerant circuit that depressurizes the refrigerant flowing out of the heat radiating unit in the first decompression unit, causes the refrigerant flowing out of the first decompression unit to flow into the heat absorbing and radiating unit, and sucks the refrigerant that has absorbed heat in the heat absorbing and radiating unit into the first compression unit. (Item 2) The refrigeration cycle apparatus according to item 1, wherein the first operation mode is an operation mode in which the heat radiation unit and the heat absorption and radiation unit radiate heat of the refrigerant to outside air and the heat absorption unit absorbs heat of the object to be cooled, thereby cooling the object to be cooled, and the second operation mode is an operation mode in which the heat radiation unit radiates heat of the refrigerant to the object to be heated, and the heat absorption and radiation unit absorbs heat of the outside air into the refrigerant, thereby heating the object to be heated. (Item 3) The refrigeration cycle apparatus according to item 1 or 2, wherein the refrigerant circuit switching unit, in a third operation mode, switches to a refrigerant circuit in which the refrigerant flowing out of the heat radiation unit flows into the first decompression unit, the refrigerant flowing out of the first decompression unit flows into the heat absorption and radiation unit, the refrigerant flowing out of the heat absorption and radiation unit is decompressed by the second decompression unit, and the refrigerant flowing out of the heat absorption and radiation unit is drawn into the first compression unit.(Item 4) A refrigerant compressor includes a first compression section (111) that compresses and discharges a refrigerant, a heat dissipation section (12) that dissipates heat from the refrigerant discharged from the first compression section, a first pressure reduction section (14a) that depressurizes the refrigerant, a second compression section (112) that compresses and discharges the refrigerant, a heat absorption and dissipation section (16) that absorbs or dissipates heat from the refrigerant, a second pressure reduction section (14b) that depressurizes the refrigerant, a heat absorption section (18) that absorbs heat into the refrigerant depressurized by the second pressure reduction section, and a refrigerant circuit switching section (15a...15e) that switches a refrigerant circuit through which the refrigerant is circulated, In a first operation mode, the refrigerant circuit switching unit switches to a refrigerant circuit that causes the refrigerant flowing out of the heat radiating unit to be sucked into the second compression unit, causes the refrigerant discharged from the second compression unit to flow into the heat absorbing and radiating unit, depressurizes the refrigerant that has radiated heat in the heat absorbing and radiating unit in the second depressurization unit, and sucks the refrigerant flowing out of the heat absorbing unit into the first compression unit; and in a third operation mode, the refrigerant circuit switching unit switches to a refrigerant circuit that causes the refrigerant flowing out of the heat radiating unit to flow into the first depressurization unit, causes the refrigerant flowing out of the first depressurization unit to flow into the heat absorbing and radiating unit, depressurizes the refrigerant that has radiated heat in the heat absorbing and radiating unit in the second depressurization unit, and sucks the refrigerant flowing out of the heat absorbing unit into the first compression unit. (Item 5) The refrigeration cycle apparatus according to item 4, wherein the first operation mode is an operation mode in which the heat radiation unit and the heat absorption and radiation unit radiate heat of the refrigerant to outside air, and the heat absorption unit causes the refrigerant to absorb heat from the object to be cooled, thereby cooling the object to be cooled; and the third operation mode is an operation mode in which the heat radiation unit and at least one of the heat absorption and radiation unit radiate heat of the refrigerant to an object to be heated, and the heat absorption unit causes the refrigerant to absorb heat from the outside air, thereby heating the object to be heated.(Item 6) A refrigerant compressor includes a first compression section (111) that compresses and discharges a refrigerant, a heat dissipation section (12) that dissipates heat from the refrigerant discharged from the first compression section, a first pressure reduction section (14a) that depressurizes the refrigerant, a second compression section (112) that compresses and discharges the refrigerant, a first heat absorption and radiation section (16) that absorbs or dissipates heat from the refrigerant, a second pressure reduction section (14b) that depressurizes the refrigerant, a second heat absorption and radiation section (18) that absorbs or dissipates heat from the refrigerant flowing out from the second pressure reduction section, and a refrigerant circuit switching section (15a...15j) that switches a refrigerant circuit through which the refrigerant is circulated, In a first operation mode, the refrigerant circuit switching unit switches to a refrigerant circuit that causes the refrigerant flowing out from the heat radiating unit to be sucked into the second compression unit, causes the refrigerant discharged from the second compression unit to flow into the first heat absorption and radiating unit, depressurizes the refrigerant that has radiated heat in the first heat absorption and radiating unit in the second decompression unit, and sucks the refrigerant that has absorbed heat in the second heat absorption and radiating unit into the first compression unit; and in a fourth operation mode, the refrigerant circuit switching unit switches to a refrigerant circuit that causes the refrigerant flowing out from the heat radiating unit to flow into the second decompression unit, depressurizes the refrigerant that has radiated heat in the second heat absorption and radiating unit in the first decompression unit, causes the refrigerant flowing out from the first decompression unit to flow into the first heat absorption and radiating unit, and sucks the refrigerant that has absorbed heat in the first heat absorption and radiating unit into the first compression unit. (Item 7) The refrigeration cycle apparatus according to item 6, wherein the first operation mode is an operation mode in which the first heat absorption and radiation unit radiates heat from the refrigerant to outside air, and the second heat absorption and radiation unit causes the refrigerant to absorb heat from the object to be cooled, thereby cooling the object to be cooled; and the fourth operation mode is an operation mode in which at least one of the heat radiation unit and the second heat absorption and radiation unit radiates heat from the refrigerant to an object to be heated, and the first heat absorption and radiation unit causes the refrigerant to absorb heat from the outside air, thereby heating the object to be heated.(Item 8) A refrigerant compressor includes: a first compression section (111) that compresses and discharges a refrigerant; a first heat dissipation section (12) that dissipates heat from the refrigerant discharged from the first compression section; a second compression section (112) that compresses and discharges the refrigerant; a second heat dissipation section (16a) that dissipates heat from the refrigerant discharged from the second compression section; a second pressure reduction section (14b) that reduces the pressure of the refrigerant flowing out from the second heat dissipation section; a first heat absorption section (18) that causes the refrigerant decompressed in the second pressure reduction section to absorb heat; a fourth pressure reduction section (14d) that reduces the pressure of the refrigerant flowing out from the second heat dissipation section; a second heat absorption section (19) that causes the refrigerant decompressed in the fourth pressure reduction section to absorb heat; and a refrigerant circuit switching section (15b...15d) that switches a refrigerant circuit through which the refrigerant circulates, wherein the heat absorption performance of the first heat absorption section and the heat absorption performance of the second heat absorption section are different from each other, In a first operation mode, the refrigerant circuit switching unit switches to a refrigerant circuit that causes the refrigerant flowing out of the first heat radiating unit to be sucked into the second compressing unit, causes the refrigerant flowing out of the second heat radiating unit to flow into the second decompressing unit, and causes the refrigerant flowing out of the first heat absorbing unit to be sucked into the first compressing unit; and in a fifth operation mode, the refrigerant circuit switching unit switches to a refrigerant circuit that causes the refrigerant flowing out of the first heat radiating unit to be sucked into the second compressing unit, causes the refrigerant flowing out of the second heat radiating unit to flow into the fourth decompressing unit, and causes the refrigerant flowing out of the second heat absorbing unit to be sucked into the first compressing unit. (Item 9) The refrigeration cycle apparatus according to item 8, wherein the first operation mode is an operation mode in which the second heat radiating section radiates heat of the refrigerant to outside air and the first heat absorbing section absorbs heat of the object to be cooled, thereby cooling the object to be cooled, and the fifth operation mode is an operation mode in which the first heat radiating section radiates heat of the refrigerant to an object to be heated, while the second heat absorbing section absorbs heat of the outside air, thereby heating the object to be heated. (Item 10) The refrigeration cycle apparatus according to any one of items 1 to 5, further comprising: a high-low pressure internal heat exchange section (17) that exchanges heat between the refrigerant flowing out from the heat absorbing and radiating section and the refrigerant drawn into the first compression section.(Item 11) The refrigeration cycle device according to any one of items 1 to 5 and 10, comprising: a branching section (13d) that branches a flow of the refrigerant flowing out from the heat absorption and radiation section; and a third pressure reduction section (14c) that reduces the pressure of one of the refrigerants branched at the branching section, wherein in the first operation mode, the refrigerant flowing out from the heat radiation section and the refrigerant reduced in pressure by the third pressure reduction section are drawn into the second compression section. (Item 12) The refrigeration cycle device according to any one of items 1 to 11, wherein the refrigerant drawn into the second compression section is in a supercritical state.

[0376] Although the present disclosure has been described with reference to the embodiments, it is understood that the present disclosure is not limited to the embodiments or structures. The present disclosure also encompasses various modifications and equivalent modifications. In addition, various combinations and forms, including only one element, more than one element, or less than one element, are also within the scope and spirit of the present disclosure.

Claims

1. A refrigerant compressor comprising: a first compression section (111) that compresses and discharges a refrigerant; a heat dissipation section (12) that dissipates heat from the refrigerant discharged from the first compression section; a first pressure reduction section (14a) that depressurizes the refrigerant; a second compression section (112) that compresses and discharges the refrigerant; a heat absorption and dissipation section (16) that absorbs or dissipates heat from the refrigerant; a second pressure reduction section (14b) that depressurizes the refrigerant; a heat absorption section (18) that absorbs heat into the refrigerant depressurized by the second pressure reduction section; and a refrigerant circuit switching section (15a...15e) that switches a refrigerant circuit through which the refrigerant is circulated; In a first operation mode, the refrigerant circuit switching unit switches to a refrigerant circuit that causes the refrigerant flowing out of the heat radiating unit to be sucked into the second compression unit, causes the refrigerant discharged from the second compression unit to flow into the heat absorbing and radiating unit, depressurizes the refrigerant that has radiated heat in the heat absorbing and radiating unit in the second decompression unit, and sucks the refrigerant flowing out of the heat absorbing unit into the first compression unit; and in a second operation mode, the refrigerant circuit switching unit switches to a refrigerant circuit that depressurizes the refrigerant flowing out of the heat radiating unit in the first decompression unit, causes the refrigerant flowing out of the first decompression unit to flow into the heat absorbing and radiating unit, and sucks the refrigerant that has absorbed heat in the heat absorbing and radiating unit into the first compression unit.

2. The refrigeration cycle device according to claim 1, wherein the first operating mode is an operating mode in which the heat of the refrigerant is radiated to the outside air by the heat radiating section and the heat absorbing section, and the heat of the object to be cooled is absorbed by the refrigerant by the heat absorbing section, thereby cooling the object to be cooled; and the second operating mode is an operating mode in which the heat of the refrigerant is radiated to the object to be heated by the heat radiating section, and the heat of the outside air is absorbed by the refrigerant by the heat absorbing section, thereby heating the object to be heated.

3. The refrigeration cycle device of claim 1, wherein in the third operating mode, the refrigerant circuit switching unit switches to a refrigerant circuit that causes the refrigerant flowing out of the heat dissipation unit to flow into the first pressure reduction unit, causes the refrigerant flowing out of the first pressure reduction unit to flow into the heat absorption and dissipation unit, reduces the pressure of the refrigerant flowing out of the heat absorption and dissipation unit in the second pressure reduction unit, and sucks the refrigerant flowing out of the heat absorption unit into the first compression unit.

4. A compressor including a first compression section (111) that compresses and discharges a refrigerant, a heat dissipation section (12) that dissipates heat from the refrigerant discharged from the first compression section, a first pressure reduction section (14a) that depressurizes the refrigerant, a second compression section (112) that compresses and discharges the refrigerant, a heat absorption and dissipation section (16) that absorbs or dissipates heat from the refrigerant, a second pressure reduction section (14b) that depressurizes the refrigerant, a heat absorption section (18) that absorbs heat into the refrigerant depressurized by the second pressure reduction section, and a refrigerant circuit switching section (15a...15e) that switches a refrigerant circuit through which the refrigerant is circulated, In a first operation mode, the refrigerant circuit switching unit switches to a refrigerant circuit that causes the refrigerant flowing out of the heat radiating unit to be sucked into the second compression unit, causes the refrigerant discharged from the second compression unit to flow into the heat absorbing and radiating unit, depressurizes the refrigerant that has radiated heat in the heat absorbing and radiating unit in the second depressurization unit, and sucks the refrigerant flowing out of the heat absorbing unit into the first compression unit; and in a third operation mode, the refrigerant circuit switching unit switches to a refrigerant circuit that causes the refrigerant flowing out of the heat radiating unit to flow into the first depressurization unit, causes the refrigerant flowing out of the first depressurization unit to flow into the heat absorbing and radiating unit, depressurizes the refrigerant that has radiated heat in the heat absorbing and radiating unit in the second depressurization unit, and sucks the refrigerant flowing out of the heat absorbing unit into the first compression unit.

5. The refrigeration cycle device according to claim 4, wherein the first operating mode is an operating mode in which the heat of the refrigerant is radiated to the outside air by the heat radiating section and the heat absorbing section, and the heat of the object to be cooled is absorbed by the refrigerant by the heat absorbing section, thereby cooling the object to be cooled; and the third operating mode is an operating mode in which the heat of the refrigerant is radiated to the object to be heated by at least one of the heat radiating section and the heat absorbing section, and the heat of the outside air is absorbed by the refrigerant by the heat absorbing section, thereby heating the object to be heated.

6. A refrigerant compressor comprising: a first compression section (111) that compresses and discharges a refrigerant; a heat dissipation section (12) that dissipates heat from the refrigerant discharged from the first compression section; a first pressure reduction section (14a) that depressurizes the refrigerant; a second compression section (112) that compresses and discharges the refrigerant; a first heat absorption and radiation section (16) that absorbs or dissipates heat from the refrigerant; a second pressure reduction section (14b) that depressurizes the refrigerant; a second heat absorption and radiation section (18) that absorbs or dissipates heat from the refrigerant flowing out from the second pressure reduction section; and a refrigerant circuit switching section (15a...15j) that switches a refrigerant circuit through which the refrigerant is circulated, In a first operation mode, the refrigerant circuit switching unit switches to a refrigerant circuit that causes the refrigerant flowing out from the heat radiating unit to be sucked into the second compression unit, causes the refrigerant discharged from the second compression unit to flow into the first heat absorption and radiating unit, depressurizes the refrigerant that has radiated heat in the first heat absorption and radiating unit in the second decompression unit, and sucks the refrigerant that has absorbed heat in the second heat absorption and radiating unit into the first compression unit; and in a fourth operation mode, the refrigerant circuit switching unit switches to a refrigerant circuit that causes the refrigerant flowing out from the heat radiating unit to flow into the second decompression unit, depressurizes the refrigerant that has radiated heat in the second heat absorption and radiating unit in the first decompression unit, causes the refrigerant flowing out from the first decompression unit to flow into the first heat absorption and radiating unit, and sucks the refrigerant that has absorbed heat in the first heat absorption and radiating unit into the first compression unit.

7. A refrigeration cycle device as described in claim 6, wherein the first operating mode is an operating mode in which the first heat absorption and radiation section radiates heat from the refrigerant to the outside air, and the second heat absorption and radiation section causes the refrigerant to absorb heat from the object to be cooled, thereby cooling the object to be cooled; and the fourth operating mode is an operating mode in which the heat from the refrigerant is radiated to the object to be heated by at least one of the heat radiation section and the second heat absorption and radiation section, and the first heat absorption and radiation section causes the refrigerant to absorb heat from the outside air, thereby heating the object to be heated.

8. A refrigerant compressor comprising: a first compression section (111) that compresses and discharges a refrigerant; a first heat dissipation section (12) that dissipates heat from the refrigerant discharged from the first compression section; a second compression section (112) that compresses and discharges the refrigerant; a second heat dissipation section (16a) that dissipates heat from the refrigerant discharged from the second compression section; a second pressure reduction section (14b) that reduces the pressure of the refrigerant flowing out from the second heat dissipation section; a first heat absorption section (18) that absorbs heat into the refrigerant decompressed in the second pressure reduction section; a fourth pressure reduction section (14d) that reduces the pressure of the refrigerant flowing out from the second heat dissipation section; a second heat absorption section (19) that absorbs heat into the refrigerant decompressed in the fourth pressure reduction section; and a refrigerant circuit switching section (15b...15d) that switches a refrigerant circuit through which the refrigerant is circulated, wherein the heat absorption performance of the first heat absorption section and the heat absorption performance of the second heat absorption section are different from each other, In a first operation mode, the refrigerant circuit switching unit switches to a refrigerant circuit that causes the refrigerant flowing out of the first heat radiating unit to be sucked into the second compressing unit, causes the refrigerant flowing out of the second heat radiating unit to flow into the second decompressing unit, and causes the refrigerant flowing out of the first heat absorbing unit to be sucked into the first compressing unit; and in a fifth operation mode, the refrigerant circuit switching unit switches to a refrigerant circuit that causes the refrigerant flowing out of the first heat radiating unit to be sucked into the second compressing unit, causes the refrigerant flowing out of the second heat radiating unit to flow into the fourth decompressing unit, and causes the refrigerant flowing out of the second heat absorbing unit to be sucked into the first compressing unit.

9. The refrigeration cycle device according to claim 8, wherein the first operating mode is an operating mode in which the heat possessed by the refrigerant is radiated to the outside air at the second heat radiating section and the heat possessed by the object to be cooled is absorbed by the refrigerant at the first heat absorbing section, thereby cooling the object to be cooled; and the fifth operating mode is an operating mode in which the heat possessed by the refrigerant is radiated to the object to be heated at the first heat radiating section and the heat possessed by the outside air is absorbed by the refrigerant at the second heat absorbing section, thereby heating the object to be heated.

10. A refrigeration cycle device as described in claim 1, further comprising a high-low pressure internal heat exchange section (17) for exchanging heat between the refrigerant flowing out from the heat absorption and radiation section and the refrigerant being drawn into the first compression section.

11. A refrigeration cycle device as described in claim 1, comprising: a branching section (13d) that branches the flow of the refrigerant flowing out from the heat absorption and radiation section; and a third pressure reduction section (14c) that reduces the pressure of one of the refrigerants branched at the branching section, wherein in the first operating mode, the refrigerant flowing out from the heat radiation section and the refrigerant reduced in pressure at the third pressure reduction section are drawn into the second compression section.

12. A refrigeration cycle device according to any one of claims 1 to 11, wherein the refrigerant drawn into the second compression section is in a supercritical state.

Images