Heat pump cycle device

Abstract

To provide a heat pump cycle device capable of properly protecting a compressor even when an operation mode is switched.SOLUTION: An air conditioner 1 for a vehicle which is a heat pump cycle device includes an accumulator 23, a compressor 11, and an operation mode switching part. The operation mode switching part switches between a first operation mode, and a second operation mode in which a suction side refrigerant pressure PS which is a refrigerant pressure in the accumulator 23 becomes lower than that in the first operation mode. In a refrigerant flow passage where a refrigerant does not circulate when switched to the first operation mode, a flow passage 24 for recovery is formed capable of allowing the refrigerant to flow in. When the operation switching part switches the operation mode from the first operation mode to the second operation mode, by allowing the refrigerant to flow into the flow passage 24 for recovery, liquid volume reduction control is performed for reducing a liquid phase refrigerant amount in the accumulator 23.SELECTED DRAWING: Figure 7

Description

Technical Field

[0001] The present invention relates to a heat pump cycle device including an accumulator and configured to be able to switch operating modes.

Background Art

[0002] Conventionally, Patent Document 1 discloses a heat pump cycle device including an accumulator and configured to be able to switch operating modes. The accumulator is a low-pressure gas-liquid separator that separates the gas and liquid of the refrigerant, allows the separated gaseous refrigerant to flow out to the suction port side of the compressor, and stores the separated liquid-phase refrigerant as surplus refrigerant in the cycle.

[0003] The heat pump cycle device of Patent Document 1 is applied to a vehicle air conditioner and is configured to be able to switch operating modes such as a hot gas heating mode and an outside air heat absorption heating mode.

[0004] More specifically, in the heat pump cycle device of Patent Document 1, during the hot gas heating mode, a part of the discharged refrigerant discharged from the compressor is switched to a refrigerant circuit that flows into a heating unit. The heating unit uses the discharged refrigerant as a heat source to heat the blown air blown into the vehicle interior. Further, the refrigerant flowing out from the heating unit and the remaining discharged refrigerant discharged from the compressor are decompressed and then merged and switched to a refrigerant circuit that flows into the accumulator.

[0005] Also, during the outside air heat absorption heating mode, all of the discharged refrigerant is switched to a refrigerant circuit that flows into the heating unit. Further, the refrigerant flowing out from the heating unit is decompressed, and the outside air side heat of the outside air is absorbed by the decompressed refrigerant and switched to a refrigerant circuit that flows into the accumulator.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0007] By the way, in the hot gas heating mode of Patent Document 1, in order to improve the heating capacity of the blown air in the heating section, a means of increasing the discharge flow rate of the compressor is effective. In order to increase the discharge flow rate of the compressor, it is necessary to increase the pressure of the low-pressure side refrigerant and increase the suction density of the refrigerant sucked into the compressor. That is, in the hot gas heating mode, in order to improve the heating capacity of the blown air in the heating section, it is necessary to increase the refrigerant pressure in the accumulator.

[0008] On the other hand, in the outside air heat absorption heating mode of Patent Document 1, in order to improve the heating capacity of the blown air in the heating section, it is effective to increase the heat absorption amount of the low-pressure side refrigerant from the outside air. In order to increase the heat absorption amount of the low-pressure side refrigerant from the outside air, it is necessary to lower the saturation temperature of the low-pressure side refrigerant. That is, in the outside air heat absorption heating mode, in order to improve the heating capacity of the blown air in the heating section, it is necessary to lower the refrigerant pressure in the accumulator.

[0009] For this reason, in the heat pump cycle device of Patent Document 1, when switching from the hot gas heating mode to the outside air heat absorption heating mode, the refrigerant pressure in the accumulator may suddenly decrease.

[0010] And when the refrigerant pressure in the accumulator suddenly decreases, a so-called forming phenomenon may occur in which the liquid-phase refrigerant in the accumulator suddenly boils and the liquid-phase refrigerant is lifted up. When such a forming phenomenon occurs, the compressor sucks in a refrigerant with a low dryness, which has an adverse effect on the durability life of the compressor due to liquid compression.

[0011] In view of the above points, the present invention provides a heat pump cycle device including an accumulator and configured to be able to switch the operation mode, and aims to provide a heat pump cycle device capable of appropriately protecting the compressor.

Means for Solving the Problem

[0012] To achieve the above object, the refrigeration cycle apparatus according to claim 1 includes an accumulator (23), a compressor (11), and an operation mode switching unit (14a to 14d, 22a, 22b, 43).

[0013] The accumulator separates the gas and liquid of the refrigerant and stores the separated liquid-phase refrigerant. The compressor sucks and compresses the gas-phase refrigerant separated by the accumulator. The operation mode switching unit switches the operation mode.

[0014] As operation modes that can be switched by the operation mode switching unit, there are a first operation mode and a second operation mode in which the suction-side refrigerant pressure (PS), which is the refrigerant pressure in the accumulator, is lower than that in the first operation mode.

[0015] In a refrigerant flow path where no refrigerant flows when the operation mode switching unit switches to the first operation mode, a recovery flow path (24, 24a) that allows the refrigerant to flow in is formed.

[0016] When the operation mode switching unit switches the operation mode from the first operation mode to the second operation mode, liquid amount reduction control is performed to reduce the amount of liquid-phase refrigerant in the accumulator by causing the refrigerant to flow into the recovery flow path.

[0017] According to this, since the liquid amount reduction control is performed, when switching from the first operation mode to the second operation mode, even if the suction-side refrigerant pressure (PS) decreases, the forming phenomenon is less likely to occur, and liquid compression of the compressor (11) can be suppressed. That is, even in a heat pump cycle apparatus including an accumulator (23) and configured to be able to switch the operation mode, the compressor (11) can be appropriately protected.

[0018] Note that the reference numerals in parentheses for each means described in this column and the claims are an example showing the correspondence relationship with the specific means described in the embodiments described later.

Brief Description of the Drawings

[0019]

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Figure 17

Embodiments for Carrying Out the Invention

[0020] Hereinafter, a plurality of embodiments for carrying out the present invention will be described with reference to the drawings. In each embodiment, parts corresponding to those described in the preceding embodiment may be denoted by the same reference numerals and redundant descriptions may be omitted. When only a part of the configuration is described in each embodiment, other embodiments described previously can be applied to other parts of the configuration. Not only combinations of parts that are explicitly shown to be combinable in each embodiment, but also partial combinations of embodiments are possible as long as there is no problem with the combination, even if not explicitly stated.

[0021] (First Embodiment) The first embodiment of the heat pump cycle device according to the present invention will be described with reference to FIGS. 1 to 8. In this embodiment, the heat pump cycle device according to the present invention is applied to a vehicle air conditioner 1 mounted on an electric vehicle. An electric vehicle is a vehicle that obtains driving force for running from an electric motor. The vehicle air conditioner 1 air - conditions the vehicle interior, which is the air - conditioning target space, and also adjusts the temperature of in - vehicle devices. Therefore, the vehicle air conditioner 1 can be called an air conditioner with an in - vehicle device temperature adjustment function or an in - vehicle device temperature adjustment device with an air - conditioning function.

[0022] In the vehicle air conditioner 1, as an in-vehicle device, specifically, the temperature of the battery 70 is adjusted. The battery 70 is a secondary battery that stores electric power supplied to a plurality of in-vehicle devices operated by electricity. The battery 70 is an assembled battery formed by electrically connecting a plurality of stacked battery cells in series or in parallel. The battery cells of the present embodiment are lithium-ion batteries.

[0023] The battery 70 is a heat-generating device that generates heat during operation (i.e., during charge and discharge). When the battery 70 is at a low temperature, its output tends to decrease, and when it is at a high temperature, deterioration tends to progress. Therefore, 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). Thus, in the electric vehicle of the present embodiment, the vehicle air conditioner 1 is used to adjust the temperature of the battery 70. Of course, the in-vehicle devices whose temperature is adjusted by the vehicle air conditioner 1 are not limited to the battery 70.

[0024] The vehicle air conditioner 1 is configured to be able to switch various operation modes in order to adjust the air conditioning in the vehicle interior and the temperature of the battery 70. The vehicle air conditioner 1 includes a heat pump cycle 10, a high-temperature side heat medium circuit 30, a low-temperature side heat medium circuit 40, an interior air conditioning unit 50, a control device 60, and the like.

[0025] First, the heat pump cycle 10 will be described. The heat pump cycle 10 is a vapor compression refrigeration cycle that adjusts the temperatures of the blown air sent into the vehicle interior, the high-temperature side heat medium circulating in the high-temperature side heat medium circuit 30, and the low-temperature side heat medium circulating in the low-temperature side heat medium circuit 40. The heat pump cycle 10 is configured to be able to switch the circuit configuration of the refrigerant circuit according to the operation mode of the vehicle air conditioner 1.

[0026] In the heat pump cycle 10, an HFO-based refrigerant (specifically, R1234yf) is adopted as the refrigerant. The heat pump cycle 10 constitutes a subcritical refrigeration cycle in which the pressure of the high-pressure side refrigerant does not exceed the critical pressure of the refrigerant. Refrigerant oil for lubricating the compressor 11 is mixed in the refrigerant. The refrigerant oil is PAG oil having compatibility with the liquid-phase refrigerant. A part of the refrigerant oil circulates through the heat pump cycle 10 together with the refrigerant.

[0027] The compressor 11 sucks, compresses, and discharges the refrigerant in the heat pump cycle 10. The compressor 11 is an electric compressor that rotationally drives a fixed displacement type compression mechanism with a fixed discharge capacity by an electric motor. The rotation speed (i.e., the refrigerant discharge capacity) of the compressor 11 is controlled by a control signal output from a control device 60 described later.

[0028] The compressor 11 is disposed in a drive device chamber formed on the front side of the passenger compartment. The drive device chamber forms a space in which at least a part of devices (e.g., an electric motor for running) used for generating and adjusting the driving force for vehicle running is disposed.

[0029] The inlet side of the first three-way joint 12a is connected to the discharge port of the compressor 11. The first three-way joint 12a has three inlets and outlets communicating with each other. As the first three-way joint 12a, a joint part formed by joining a plurality of pipes or a joint part formed by providing a plurality of refrigerant passages in a metal block or a resin block can be adopted.

[0030] Furthermore, as will be described later, the heat pump cycle 10 includes a second three-way joint 12b to a sixth three-way joint 12f. The basic configuration of the second three-way joint 12b to the sixth three-way joint 12f is the same as that of the first three-way joint 12a. Furthermore, the basic configuration of the three-way joint described in the embodiments described later is also the same as that of the first three-way joint 12a.

[0031] When one of these three-way joints is used as an inlet and the remaining two are used as outlets, it serves as a branch section for splitting the refrigerant flow. Also, when two of the three inlets / outlets are used as inlets and the remaining one is used as an outlet, it serves as a confluence section for merging the refrigerant flow. The first three-way joint 12a serves as a discharge-side branch section for splitting the flow of the discharged refrigerant from the compressor 11.

[0032] On one outlet of the first three-way joint 12a, the inlet side of the refrigerant passage of the water-cooled medium heat exchanger 13 is connected. On the other outlet of the first three-way joint 12a, one inlet side of the sixth three-way joint 12f is connected. The refrigerant passage from the other outlet of the first three-way joint 12a to one inlet of the sixth three-way joint 12f is the bypass passage 21a. A bypass-side flow rate adjustment valve 14d is arranged in the bypass passage 21a.

[0033] The bypass-side flow rate adjustment valve 14d is a decompression section on the bypass passage side that decompresses the refrigerant flowing out from the other outlet of the first three-way joint 12a (i.e., the other refrigerant branched at the first three-way joint 12a) during the hot gas heating mode and the like, which will be described later. The bypass-side flow rate adjustment valve 14d is a bypass-side flow rate adjustment section that adjusts the flow rate (mass flow rate) of the refrigerant flowing through the bypass passage 21a.

[0034] The bypass-side flow rate adjustment valve 14d is an electric variable throttle mechanism having a valve body that changes the throttle opening degree and an electric actuator that displaces the valve body. As the electric actuator, a stepping motor or a brushless motor can be adopted. The operation of the bypass-side flow rate adjustment valve 14d is controlled by a control signal output from the control device 60.

[0035] The bypass-side flow rate adjustment valve 14d has a fully open function in which, by fully opening the valve opening degree, it functions as merely a refrigerant passage with hardly any refrigerant decompression action and flow rate adjustment action. The bypass-side flow rate adjustment valve 14d has a fully closed function in which, by fully closing the valve opening degree, it blocks the refrigerant passage.

[0036] Furthermore, as will be described later, the heat pump cycle 10 includes a heating expansion valve 14a, a cooling expansion valve 14b, and a cooling expansion valve 14c. The basic configurations of the heating expansion valve 14a, the cooling expansion valve 14b, and the cooling expansion valve 14c are the same as those of the bypass side flow rate adjustment valve 14d.

[0037] The heating expansion valve 14a, the cooling expansion valve 14b, the cooling expansion valve 14c, and the bypass side flow rate adjustment valve 14d can switch the refrigerant circuit by exerting the fully closed function described above. Therefore, the heating expansion valve 14a, the cooling expansion valve 14b, the cooling expansion valve 14c, and the bypass side flow rate adjustment valve 14d are operation mode switching units that switch the operation mode by switching the refrigerant circuit.

[0038] Of course, the heating expansion valve 14a, the cooling expansion valve 14b, the cooling expansion valve 14c, and the bypass side flow rate adjustment valve 14d may be formed by combining a variable throttle mechanism that does not have a fully closed function and an on-off valve that opens and closes a throttle passage. In this case, each on-off valve serves as an operation mode switching unit.

[0039] The water-cooled refrigerant heat exchanger 13 is a heat exchange unit that exchanges heat between the discharged refrigerant flowing out from one outlet of the first three-way joint 12a (that is, one of the refrigerants branched at the first three-way joint 12a) and the high-temperature side heat medium circulating in the high-temperature side heat medium circuit 30. In the water-cooled refrigerant heat exchanger 13, the heat possessed by the discharged refrigerant is radiated to the high-temperature side heat medium to heat the high-temperature side heat medium.

[0040] The inlet side of the second three-way joint 12b is connected to the outlet of the refrigerant passage of the water-cooled refrigerant heat exchanger 13. The inlet side of the heating expansion valve 14a is connected to one outlet of the second three-way joint 12b. One inlet side of the four-way joint 12x is connected to the other outlet of the second three-way joint 12b. The refrigerant passage from the other outlet of the second three-way joint 12b to one inlet of the four-way joint 12x is the dehumidification passage 21b.

[0041] A dehumidifying on-off valve 22a is arranged in the dehumidifying passage 21b. The dehumidifying on-off valve 22a is an on-off valve that opens and closes the dehumidifying passage 21b. The dehumidifying on-off valve 22a is a solenoid valve whose opening and closing operation is controlled by a control voltage output from the control device 60. The dehumidifying on-off valve 22a can switch the refrigerant circuit by opening and closing the dehumidifying passage 21b. Therefore, the dehumidifying on-off valve 22a is an operation mode switching unit that switches the operation mode by switching the refrigerant circuit.

[0042] The four-way joint 12x is a joint part having four inflow / outflow ports communicating with each other. As the four-way joint 12x, a joint part formed in the same manner as the aforementioned three-way joint can be adopted. As the four-way joint 12x, one formed by combining two three-way joints may be adopted.

[0043] The heating expansion valve 14a is an outdoor air pressure reducing unit that reduces the pressure of the refrigerant flowing into the outdoor heat exchanger 15 during the single outdoor air heat absorption heating mode described later and the like. Further, the heating expansion valve 14a is an outdoor air flow rate adjusting unit that adjusts the flow rate (mass flow rate) of the refrigerant flowing into the outdoor heat exchanger 15.

[0044] The refrigerant inlet side of the outdoor heat exchanger 15 is connected to the outlet of the heating expansion valve 14a. The outdoor heat exchanger 15 is an outdoor heat exchange unit that exchanges heat between the refrigerant flowing out from the heating expansion valve 14a and the outdoor air blown by an outdoor air fan (not shown). The outdoor heat exchanger 15 is arranged on the front side of the drive device chamber. For this reason, during vehicle travel, the traveling wind flowing into the drive device chamber through the grill can be applied to the outdoor heat exchanger 15.

[0045] The outdoor heat exchanger 15 becomes an outdoor heat radiation unit that radiates the heat of the refrigerant to the outdoor air during the single cooling mode described later and the like. The outdoor heat exchanger 15 becomes an outdoor heat absorption unit that absorbs the outdoor air side heat of the outdoor air by the refrigerant during the single outdoor air heat absorption heating mode described later and the like.

[0046] The inlet side of the third three-way joint 12c is connected to the refrigerant outlet of the outdoor heat exchanger 15. The other inlet side of the four-way joint 12x is connected to one of the outlets of the third three-way joint 12c via the first check valve 16a. The inlet side of one of the fourth three-way joints 12d is connected to the other outlet of the third three-way joint 12c. The refrigerant passage from the other outlet of the third three-way joint 12c to the inlet of one of the fourth three-way joints 12d is the heating passage 21c.

[0047] A heating on-off valve 22b is arranged in the heating passage 21c. The heating on-off valve 22b is an on-off valve that opens and closes the heating passage 21c. The basic structure of the heating on-off valve 22b is the same as that of the dehumidifying on-off valve 22a. The heating on-off valve 22b can switch the refrigerant circuit by opening and closing the heating passage 21c. Therefore, the heating on-off valve 22b is an operation mode switching unit that switches the operation mode by switching the refrigerant circuit.

[0048] Here, when the heating on-off valve 22b closes the heating passage 21c, the refrigerant cannot flow through the heating passage 21c in either the forward or reverse direction.

[0049] That is, when the heating on-off valve 22b closes the heating passage 21c, the refrigerant cannot flow from the other outlet side of the third three-way joint 12c to the inlet of one of the fourth three-way joints 12d through the heating passage 21c. Further, when the heating on-off valve 22b closes the heating passage 21c, the refrigerant cannot flow from the inlet of one of the fourth three-way joints 12d to the other outlet side of the third three-way joint 12c through the heating passage 21c. This also applies to the dehumidifying on-off valve 22a.

[0050] The first check valve 16a allows the refrigerant to flow from the third three-way joint 12c side to the four-way joint 12x side and prohibits the refrigerant from flowing from the four-way joint 12x side to the third three-way joint 12c side.

[0051] One outlet of the four-way joint 12x is connected to the refrigerant inlet side of the indoor evaporator 18 via the cooling expansion valve 14b. The cooling expansion valve 14b is a pressure reducing section for the evaporator that reduces the pressure of the refrigerant flowing out from one outlet of the four-way joint 12x during the single cooling mode or the like described later. Further, the cooling expansion valve 14b is a flow rate adjusting section for the evaporator that adjusts the flow rate (mass flow rate) of the refrigerant flowing into the indoor evaporator 18.

[0052] The indoor evaporator 18 is disposed in the air conditioning case 51 of the indoor air conditioning unit 50 described later. The indoor evaporator 18 is a cooling evaporating section that exchanges heat between the low-pressure refrigerant decompressed by the cooling expansion valve 14b and the blown air blown from the indoor blower 52 into the vehicle interior. In the indoor evaporator 18, the blown air is cooled by evaporating the low-pressure refrigerant and exerting an endothermic effect.

[0053] One inlet side of the fifth three-way joint 12e is connected to the refrigerant outlet of the indoor evaporator 18 via the second check valve 16b. The second check valve 16b allows the refrigerant to flow from the refrigerant outlet side of the indoor evaporator 18 to the fifth three-way joint 12e side, and prohibits the refrigerant from flowing from the fifth three-way joint 12e side to the refrigerant outlet side of the indoor evaporator 18.

[0054] The other outlet of the four-way joint 12x is connected to the other inlet side of the sixth three-way joint 12f via the cooling expansion valve 14c. The inlet side of the refrigerant passage of the chiller 20 is connected to the outlet of the sixth three-way joint 12f.

[0055] The cooling expansion valve 14c is a pressure reducing section for equipment that reduces the pressure of the refrigerant flowing into the chiller 20 during the cooling and cooling mode or the hot gas heating mode described later. Further, the cooling expansion valve 14c is a flow rate adjusting section for equipment that adjusts the flow rate (mass flow rate) of the refrigerant flowing into the chiller 20.

[0056] The chiller 20 exchanges heat between the low-pressure refrigerant decompressed by the cooling expansion valve 14c and the low-temperature-side heat medium circulating in the low-temperature-side heat medium circuit 40 to evaporate the low-pressure refrigerant. In the chiller 20, the low-pressure refrigerant is evaporated to exert an endothermic effect, thereby cooling the low-temperature-side heat medium.

[0057] The other inlet side of the fourth three-way joint 12d is connected to the outlet of the refrigerant passage of the chiller 20. The other inlet side of the fifth three-way joint 12e is connected to the outlet of the fourth three-way joint 12d.

[0058] The inlet side of the accumulator 23 is connected to the outlet of the fifth three-way joint 12e. The accumulator 23 is a low-pressure gas-liquid separator arranged to separate the gas and liquid of the refrigerant flowing into the interior, let the separated gas-phase refrigerant flow out to the suction inlet side of the compressor 11, and store the separated liquid-phase refrigerant as the surplus refrigerant of the cycle. Therefore, the gas-phase refrigerant outlet of the accumulator 23 is connected to the suction inlet side of the compressor 11.

[0059] Next, the high-temperature-side heat medium circuit 30 will be described. The high-temperature-side heat medium circuit 30 is a heat medium circulation circuit that circulates the high-temperature-side heat medium. In the present embodiment, an ethylene glycol aqueous solution is employed as the high-temperature-side heat medium. In the high-temperature-side heat medium circuit 30, a heat medium passage of the water-cooled heat exchanger 13, a high-temperature-side pump 31, a heater core 32, etc. are arranged.

[0060] The high-temperature-side pump 31 is a high-temperature-side heat medium pumping unit that pumps the high-temperature-side heat medium flowing out from the heat medium passage of the water-cooled heat exchanger 13 to the heat medium inlet side of the heater core 32. The high-temperature-side pump 31 is an electric pump whose rotation speed (i.e., pumping capacity) is controlled by a control voltage output from the control device 60.

[0061] The heater core 32 is a heat exchanger for heating the blown air by exchanging heat between the high-temperature side heat medium heated by the water-cooled medium heat exchanger 13 and the blown air that has passed through the indoor evaporator 18. The heater core 32 is disposed within the air-conditioning case 51 of the indoor air-conditioning unit 50. The inlet side of the heat medium passage of the water-cooled medium heat exchanger 13 is connected to the heat medium outlet of the heater core 32.

[0062] Therefore, each component device disposed in the water-cooled medium heat exchanger 13 and the high-temperature side heat medium circuit 30 of the present embodiment is a heating unit that heats the blown air, which is an object to be heated, using one of the discharged refrigerants branched by the first three-way joint 12a as a heat source.

[0063] Next, the low-temperature side heat medium circuit 40 will be described. The low-temperature side heat medium circuit 40 is a heat medium circuit that circulates the low-temperature side heat medium. In the present embodiment, the same type of fluid as the high-temperature side heat medium is employed as the low-temperature side heat medium. The low-temperature side heat medium circuit 40 is connected to a low-temperature side pump 41, a cooling water passage 70a of the battery 70, a heat medium passage of the chiller 20, and the like.

[0064] The low-temperature side pump 41 is a low-temperature side heat medium pumping unit that pumps the low-temperature side heat medium flowing out from the cooling water passage 70a of the battery 70 to the inlet side of the heat medium passage of the chiller 20. The basic configuration of the low-temperature side pump 41 is the same as that of the high-temperature side pump 31. The inlet side of the cooling water passage 70a of the battery 70 is connected to the outlet side of the heat medium passage of the chiller 20.

[0065] The cooling water passage 70a of the battery 70 is a cooling water passage formed to cool the battery 70 by allowing the low-temperature side heat medium cooled by the chiller 20 to flow therethrough. The cooling water passage 70a is formed inside a battery dedicated case that houses a plurality of stacked battery cells.

[0066] The passage structure of the cooling water passage 70a is a passage structure in which a plurality of passages are connected in parallel inside the battery dedicated case. As a result, in the cooling water passage 70a, all the battery cells can be cooled evenly. The suction port side of the low-temperature side pump 41 is connected to the outlet of the cooling water passage 70a.

[0067] Therefore, the chiller 20 of the present embodiment serves as a heat absorption unit for equipment that absorbs the heat generated by the battery 70 into the refrigerant through the low-temperature side heat medium during the waste heat recovery heating mode and the like, which will be described later.

[0068] Next, the indoor air conditioning unit 50 will be described. The indoor air conditioning unit 50 is a unit that integrates a plurality of component devices in order to blow out the blown air adjusted to an appropriate temperature for air conditioning in the vehicle interior to an appropriate location in the vehicle interior. The indoor air conditioning unit 50 is disposed inside the instrument panel at the foremost part of the vehicle interior.

[0069] The indoor air conditioning unit 50 is formed by accommodating an indoor blower 52, an indoor evaporator 18, a heater core 32, etc. in an air conditioning case 51 that forms an air passage for the blown air. The air conditioning case 51 is made of a resin (for example, polypropylene) having a certain degree of elasticity and excellent strength.

[0070] An inside / outside air switching device 53 is disposed on the most upstream side of the blown air flow in the air conditioning case 51. The inside / outside air switching device 53 switches and introduces inside air (that is, vehicle interior air) and outside air (that is, vehicle exterior air) into the air conditioning case 51. The operation of the inside / outside air switching device 53 is controlled by a control signal output from the control device 60.

[0071] An indoor blower 52 is disposed on the downstream side of the blown air flow of the inside / outside air switching device 53. The indoor blower 52 is a blowing unit that blows the air inhaled through the inside / outside air switching device 53 toward the vehicle interior. The rotational speed (that is, the blowing capacity) of the indoor blower 52 is controlled by a control voltage output from the control device 60.

[0072] On the downstream side of the air flow of the indoor blower 52, an indoor evaporator 18 and a heater core 32 are arranged. The indoor evaporator 18 is arranged on the upstream side of the air flow with respect to the heater core 32. Inside the air conditioning case 51, a cold air bypass passage 55 is formed to allow the air flow after passing through the indoor evaporator 18 to flow around the heater core 32.

[0073] An air mix door 54 is arranged on the downstream side of the air flow of the indoor evaporator 18 in the air conditioning case 51 and on the upstream side of the air flow of the heater core 32 and the cold air bypass passage 55.

[0074] The air mix door 54 adjusts the air volume ratio between the air volume of the air flow passing through the heater core 32 side and the air volume of the air flow passing through the cold air bypass passage 55 among the air flow after passing through the indoor evaporator 18. The actuator for driving the air mix door 54 has its operation controlled by a control signal output from the control device 60.

[0075] A mixing space 56 is arranged on the downstream side of the air flow of the heater core 32 and the cold air bypass passage 55. The mixing space 56 is a space for mixing the air flow heated by the heater core 32 and the air flow that has passed through the cold air bypass passage 55 and has not been heated.

[0076] Therefore, in the indoor air conditioning unit 50, by adjusting the opening degree of the air mix door 54, the temperature of the air flow (i.e., the conditioned air) mixed in the mixing space 56 and blown into the vehicle interior can be adjusted. The air mix door 54 of the present embodiment is a flow rate adjustment unit that adjusts the flow rate of the air flow heat-exchanged by the heater core 32.

[0077] At the most downstream part of the air flow of the air conditioning case 51, a plurality of opening holes (not shown) for blowing the conditioned air toward various locations in the vehicle interior are formed. For each of the plurality of opening holes, a blow mode door (not shown) for opening and closing each opening hole is arranged. The actuator for driving the blow mode door has its operation controlled by a control signal output from the control device 60.

[0078] Therefore, in the in-vehicle air-conditioning unit 50, by switching the opening hole through which the blow mode door opens and closes, conditioned air adjusted to an appropriate temperature can be blown out to an appropriate location in the vehicle interior.

[0079] Next, the electric control unit of the present embodiment will be described with reference to the block diagram of FIG. 2. The control device 60 includes a well-known microcomputer including a CPU, a ROM, a RAM, etc. and its peripheral circuits. The control device 60 performs various calculations and processes based on the control programs stored in the ROM. Then, the control device 60 controls the operations of various controlled devices connected to the output side based on the calculation and processing results.

[0080] On the input side of the control device 60, a group of control sensors such as an in-vehicle temperature sensor 61a, an outside air temperature sensor 61b, a solar radiation sensor 61c, a discharged refrigerant temperature and pressure sensor 62a, a high-pressure side refrigerant temperature and pressure sensor 62b, an outdoor unit side refrigerant temperature and pressure sensor 62c, an evaporator side refrigerant temperature and pressure sensor 62d, a chiller side refrigerant temperature and pressure sensor 62e, a suction refrigerant pressure sensor 62f, a high-temperature side heat medium temperature sensor 63a, a low-temperature side heat medium temperature sensor 63b, a battery temperature sensor 64, and an air-conditioning air temperature sensor 65 are connected.

[0081] The in-vehicle temperature sensor 61a is an in-vehicle temperature detection unit that detects the in-vehicle temperature (in-vehicle temperature) Tr. The outside air temperature sensor 61b is an outside air temperature detection unit that detects the outside air temperature (outside air temperature) Tam outside the vehicle. The solar radiation sensor 61c is a solar radiation amount detection unit that detects the amount of solar radiation As irradiated into the vehicle interior.

[0082] The discharged refrigerant temperature and pressure sensor 62a is a discharged refrigerant temperature and pressure detection unit that detects the discharged refrigerant temperature Td and the discharged refrigerant pressure Pd of the discharged refrigerant discharged from the compressor 11.

[0083] The high-pressure side refrigerant temperature and pressure sensor 62b is a high-pressure side refrigerant temperature and pressure detection unit that detects the high-pressure side refrigerant temperature T1 and the high-pressure side refrigerant pressure P1 of the refrigerant flowing out from the water-cooled refrigerant heat exchanger 13.

[0084] The outdoor unit side refrigerant temperature and pressure sensor 62c is an outdoor unit side refrigerant temperature and pressure detection unit that detects the outdoor unit side refrigerant temperature T2 and the outdoor unit side refrigerant pressure P2 of the refrigerant flowing out of the outdoor heat exchanger 15.

[0085] The evaporator side refrigerant temperature and pressure sensor 62d is an evaporator side refrigerant temperature and pressure detection unit that detects the evaporator side refrigerant temperature Te and the evaporator side refrigerant pressure Pe of the refrigerant flowing out of the indoor evaporator 18.

[0086] The chiller side refrigerant temperature and pressure sensor 62e is a chiller side refrigerant temperature and pressure detection unit that detects the chiller side refrigerant temperature Tc and the chiller side refrigerant pressure Pc of the refrigerant flowing out of the refrigerant passage of the chiller 20.

[0087] Also, in this embodiment, as the refrigerant temperature and pressure sensor, a detection unit in which a pressure detection unit and a temperature detection unit are integrated is adopted. Of course, a pressure detection unit and a temperature detection unit configured separately may also be adopted.

[0088] The suction refrigerant pressure sensor 62f is a suction refrigerant temperature detection unit that detects the suction side refrigerant pressure PS, which is the pressure of the refrigerant in the accumulator 23.

[0089] The high-temperature side heat medium temperature sensor 63a is a high-temperature side heat medium temperature detection unit that detects the high-temperature side heat medium temperature TWH, which is the temperature of the high-temperature side heat medium flowing into the heater core 32. The low-temperature side heat medium temperature sensor 63b is a low-temperature side heat medium temperature detection unit that detects the low-temperature side heat medium temperature TWL, which is the temperature of the low-temperature side heat medium flowing into the cooling water passage 70a of the battery 70.

[0090] The battery temperature sensor 64 is a battery temperature detection unit that detects the battery temperature TB, which is the temperature of the battery 70. The battery temperature sensor 64 has a plurality of temperature sensors and detects the temperatures at a plurality of locations of the battery 70. Therefore, the control device 60 can detect the temperature difference and temperature distribution of each battery cell forming the battery 70. Furthermore, as the battery temperature TB, the average value of the detection values of the plurality of temperature sensors is adopted.

[0091] The air-conditioning air temperature sensor 65 is an air-conditioning air temperature detection unit that detects the supply air temperature TAV, which is the temperature of the supply air blown from the mixing space 56 into the vehicle interior.

[0092] Furthermore, as shown in FIG. 2, an operation panel 69 disposed near the instrument panel at the front of the vehicle interior is connected to the input side of the control device 60. Operation signals from various operation switches provided on the operation panel 69 are input to the control device 60.

[0093] 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, and the like.

[0094] The auto switch is an automatic control setting unit that sets or cancels the automatic control operation of the vehicle air conditioner 1. The air conditioner switch is a cooling request unit that requests cooling of the supply air by the in-vehicle evaporator 18. The air volume setting switch is an air volume setting unit that manually sets the air volume of the in-vehicle blower 52. The temperature setting switch is a temperature setting unit that sets the set temperature Tset in the vehicle interior.

[0095] Note that the control device 60 of the present embodiment is configured such that a control unit that controls various controlled devices connected to its output side is integrally formed. Therefore, the configurations (hardware and software) that control the operations of the respective controlled devices constitute a control unit that controls the operations of the respective controlled devices.

[0096] For example, among the control device 60, the configuration that controls the rotational speed of the compressor 11 constitutes a discharge capacity control unit 60a. The configuration that controls the operation of the operation mode switching unit constitutes an operation mode switching control unit 60b.

[0097] Next, the operation of the vehicle air conditioner 1 of the present embodiment in the above configuration will be described. In the vehicle air conditioner 1, various operation modes are switched in order to perform air conditioning in the vehicle interior and adjust the temperature of the battery 70. The switching of the operation mode is performed by executing a control program stored in advance in the control device 60.

[0098] The control program is executed not only when the start switch (so-called IG switch) of the vehicle system is turned on and the vehicle system is activated, but also when the battery 70 is being charged from an external power source.

[0099] In the control program, the detection signals of the above-described control sensor group and the operation signals of the operation panel are read. Then, based on the read detection signals and operation signals, the target blow-out temperature TAO, which is the target temperature of the blown air to be blown into the vehicle interior, is calculated. Further, based on the detection signals, operation signals, target blow-out temperature TAO, etc., an operation mode is selected, and the operation of various controlled devices is controlled according to the selected operation mode.

[0100] Thereafter, until the end condition of the control program is satisfied, the control routines such as reading of the above-described detection signals and operation signals, calculation of the target blow-out temperature TAO, selection of the operation mode, and control of various controlled devices are repeated at a predetermined control cycle.

[0101] The target blow-out temperature TAO is calculated using the internal air temperature Tr detected by the internal air temperature sensor 61a, the outside air temperature Tam detected by the outside air temperature sensor 61b, the solar radiation amount As detected by the solar radiation sensor 61c, the set temperature Tset set by the temperature setting switch, and the like. Each operation mode will be described below.

[0102] (a) Cooling mode The cooling mode is an operation mode in which the vehicle interior is cooled by blowing out the cooled blown air into the vehicle interior. The cooling mode is likely to be selected when the outside air temperature Tam is relatively high or when the target blow-out temperature TAO is relatively low.

[0103] In the cooling mode, there are a single cooling mode for cooling the interior of the vehicle without cooling the battery 70, and a cooling and cooling mode for cooling the battery 70 and cooling the interior of the vehicle. In the control program of the present embodiment, when the battery temperature TB detected by the battery temperature sensor 64 becomes equal to or higher than a predetermined reference upper limit temperature KTBH, an operation mode for cooling the battery 70 is executed.

[0104] (a-1) Single cooling mode In the heat pump cycle 10 of the single cooling mode, the control device 60 fully opens the heating expansion valve 14a, sets the cooling expansion valve 14b in a throttle state that exhibits a refrigerant pressure reducing action, fully closes the cooling expansion valve 14c, and fully closes the bypass side flow rate adjustment valve 14d. Further, the control device 60 closes the dehumidification on-off valve 22a and closes the heating on-off valve 22b.

[0105] Therefore, in the heat pump cycle 10 of the single cooling mode, the refrigerant discharged from the compressor 11 is switched to a refrigerant circuit that circulates in the order of the water-cooled heat exchanger 13, the fully open heating expansion valve 14a, the outdoor heat exchanger 15, the throttle state cooling expansion valve 14b, the indoor evaporator 18, the accumulator 23, and the suction port of the compressor 11.

[0106] In the high-temperature side heat medium circuit 30 of the single cooling mode, the control device 60 operates the high-temperature side pump 31 so as to exhibit a predetermined reference pressure feeding capacity. Therefore, in the high-temperature side heat medium circuit 30 of the single cooling mode, the high-temperature side heat medium pumped from the high-temperature side pump 31 circulates in the order of the heater core 32, the heat medium passage of the water-cooled heat exchanger 13, and the suction port of the high-temperature side pump 31.

[0107] In the indoor air conditioner unit 50 of the single cooling mode, the control device 60 controls the rotation speed of the indoor blower 52 by referring to a control map stored in the control device 60 in advance based on the target blowing temperature TAO.

[0108] Further, the control device 60 adjusts the opening degree of the air mix door 54 so that the blown air temperature TAV detected by the air-conditioning air temperature sensor 65 approaches the target blowing temperature TAO. Further, the control device 60 appropriately controls the operation of other controlled devices.

[0109] Therefore, in the heat pump cycle 10 in the single cooling mode, the water-cooled refrigerant heat exchanger 13 and the outdoor heat exchanger 15 function as condensers that dissipate and condense the refrigerant, and the indoor evaporator 18 functions as an evaporator that evaporates the refrigerant, constituting a vapor compression refrigeration cycle.

[0110] Here, the refrigerant evaporation pressure in the indoor evaporator 18 in the single cooling mode is adjusted so as to suppress frosting of the indoor evaporator 18. More specifically, in the present embodiment, the saturation temperature of the refrigerant in the indoor evaporator 18 is adjusted to be 2°C or higher. Also, although the suction-side refrigerant pressure PS in the single cooling mode may decrease due to pressure loss, it is generally equivalent to the refrigerant evaporation pressure in the indoor evaporator 18.

[0111] In the high-temperature side heat medium circuit 30 in the single cooling mode, the high-temperature side heat medium that has flowed into the heat medium passage of the water-cooled refrigerant heat exchanger 13 exchanges heat with the refrigerant discharged from the compressor 11 and is heated. The high-temperature side heat medium heated by the water-cooled refrigerant heat exchanger 13 is sucked into the high-temperature side pump 31 and pumped to the heater core 32.

[0112] The high-temperature side heat medium that has flowed into the heater core 32 exchanges heat with the blown air. Thereby, the blown air is heated. The high-temperature side heat medium that has flowed out of the heater core 32 flows into the heat medium passage of the water-cooled refrigerant heat exchanger 13.

[0113] In the indoor air conditioning unit 50 in the single cooling mode, when the blown air sent from the indoor blower 52 passes through the indoor evaporator 18, it is cooled by absorbing heat from the refrigerant. The blown air cooled by the indoor evaporator 18 is reheated by exchanging heat with the high-temperature side heat medium in the heater core 32 according to the opening degree of the air mix door 54. Then, the blown air whose temperature is adjusted to approach the target blow-out temperature TAO is blown into the vehicle interior. Thereby, cooling in the vehicle interior is realized.

[0114] (a-2) Cooling and air-conditioning mode In the heat pump cycle 10 in the cooling and air-conditioning mode, the control device 60 sets the cooling expansion valve 14c in a throttled state with respect to the single cooling mode.

[0115] Therefore, in the heat pump cycle 10 in the cooling and air-conditioning mode, the refrigerant discharged from the compressor 11 circulates in the same manner as in the single cooling mode. At the same time, the refrigerant discharged from the compressor 11 is switched to a refrigerant circuit that circulates in the order of the water-cooled heat exchanger 13, the heating expansion valve 14a in the fully open state, the outdoor heat exchanger 15, the cooling expansion valve 14c in the throttled state, the chiller 20, the accumulator 23, and the suction port of the compressor 11. That is, the indoor evaporator 18 and the chiller 20 are switched to a refrigerant circuit connected in parallel with respect to the flow of the refrigerant.

[0116] Also, in the high-temperature side heat medium circuit 30 in the cooling and air-conditioning mode, the high-temperature side heat medium pumped from the high-temperature side pump 31 circulates in the same manner as in the single cooling mode.

[0117] Also, in the low-temperature side heat medium circuit 40 in the cooling and air-conditioning mode, the control device 60 operates the low-temperature side pump 41 so as to exhibit a predetermined reference pumping capacity. Therefore, in the low-temperature side heat medium circuit 40 in the cooling and air-conditioning mode, the low-temperature side heat medium pumped from the low-temperature side pump 41 circulates in the order of the heat medium passage of the chiller 20, the cooling water passage 70a of the battery 70, and the suction port of the low-temperature side pump 41.

[0118] Also, in the indoor air conditioning unit 50 in the cooling and cooling mode, similar to the single cooling mode, the control device 60 controls the rotation speed of the indoor blower 52, the opening degree of the air mix door 54, etc. Further, the control device 60 appropriately controls the operation of other controlled devices.

[0119] Therefore, in the heat pump cycle 10 in the cooling and cooling mode, a vapor compression refrigeration cycle is configured in which the water-cooled refrigerant heat exchanger 13 and the outdoor heat exchanger 15 function as condensers, and the indoor evaporator 18 and the chiller 20 function as evaporators. The suction-side refrigerant pressure PS in the cooling and cooling mode is equivalent to that in the single cooling mode.

[0120] In the high-temperature side heat medium circuit 30 in the cooling and cooling mode, similar to the single cooling mode, the high-temperature side heat medium heated by the water-cooled refrigerant heat exchanger 13 is pumped to the heater core 32.

[0121] In the low-temperature side heat medium circuit 40 in the cooling and cooling mode, the low-temperature side heat medium flowing into the heat medium passage of the chiller 20 exchanges heat with the low-pressure side refrigerant decompressed by the cooling expansion valve 14c and is cooled. The low-temperature side heat medium cooled by the chiller 20 flows into the cooling water passage 70a of the battery 70. The low-temperature side heat medium flowing into the cooling water passage 70a of the battery 70 absorbs the heat generated by the device side of the battery 70. Thereby, the battery 70 is cooled.

[0122] The low-temperature side heat medium flowing out from the cooling water passage 70a of the battery 70 is sucked by the low-temperature side pump 41 and pumped to the heat medium passage of the chiller 20. Therefore, in the chiller 20 in the cooling and cooling mode, the refrigerant absorbs the heat generated by the device side of the battery 70 through the low-temperature side heat medium.

[0123] In the indoor air conditioning unit 50 in the cooling and cooling mode, similar to the single cooling mode, the temperature-adjusted blown air is blown into the vehicle interior, thereby realizing cooling in the vehicle interior.

[0124] (b) Dehumidifying and heating mode The dehumidifying and heating mode is an operation mode that dehumidifies and heats the interior of the vehicle by reheating the cooled and dehumidified blown air and blowing it into the vehicle interior. The dehumidifying and heating mode is likely to be selected when the outside air temperature Tam is in the intermediate temperature range or when the target blow-out temperature TAO is in the intermediate temperature range.

[0125] The dehumidifying and heating mode includes a single dehumidifying and heating mode that dehumidifies and heats the interior of the vehicle without cooling the battery 70, and a cooling dehumidifying and heating mode that cools the battery 70 and dehumidifies and heats the interior of the vehicle.

[0126] (b-1) Single dehumidifying and heating mode In the heat pump cycle 10 of the single dehumidifying and heating mode, the control device 60 fully closes the heating expansion valve 14a, throttles the cooling expansion valve 14b, fully closes the cooling expansion valve 14c, and fully closes the bypass side flow rate adjustment valve 14d. Also, the control device 60 opens the dehumidifying on-off valve 22a and closes the heating on-off valve 22b.

[0127] Therefore, in the heat pump cycle 10 of the single dehumidifying and heating mode, as shown by the solid line arrows in FIG. 3, the refrigerant discharged from the compressor 11 is switched to a refrigerant circuit that circulates in the order of the water-cooled medium heat exchanger 13, the dehumidifying passage 21b, the cooling expansion valve 14b in the throttled state, the indoor evaporator 18, the accumulator 23, and the suction port of the compressor 11.

[0128] Also, in the high-temperature side heat medium circuit 30 of the single dehumidifying and heating mode, as shown by the broken line arrows in FIG. 3, the high-temperature side heat medium pumped from the high-temperature side pump 31 circulates in the same manner as in the single cooling mode.

[0129] Also, in the indoor air-conditioning unit 50 of the single dehumidifying and heating mode, the control device 60 controls the rotation speed of the indoor blower 52, the opening degree of the air mix door 54, etc. in the same manner as in the single cooling mode. Further, the control device 60 appropriately controls the operation of other controlled devices.

[0130] Therefore, in the heat pump cycle 10 of the independent dehumidifying and heating mode, a vapor compression refrigeration cycle is configured in which the water-cooled refrigerant heat exchanger 13 functions as a condenser and the indoor evaporator 18 functions as an evaporator.

[0131] Here, the refrigerant evaporation pressure in the indoor evaporator 18 in the independent dehumidifying and heating mode is adjusted so that the supply air can be dehumidified by the indoor evaporator 18 and the frosting of the indoor evaporator 18 can be suppressed. More specifically, the saturation temperature of the refrigerant in the indoor evaporator 18 is adjusted to be lower than the outside air temperature Tam and 2°C or higher. Although the suction-side refrigerant pressure PS in the independent dehumidifying and heating mode may decrease due to pressure loss, it is generally equivalent to the refrigerant evaporation pressure in the indoor evaporator 18.

[0132] In the high-temperature side heat medium circuit 30 of the independent dehumidifying and heating mode, similar to the independent cooling mode, the high-temperature side heat medium heated by the water-cooled refrigerant heat exchanger 13 is pumped to the heater core 32.

[0133] In the indoor air conditioner unit 50 of the independent dehumidifying and heating mode, the supply air cooled and dehumidified by the indoor evaporator 18 is reheated by the heater core 32. Then, the temperature-adjusted supply air is blown into the vehicle interior, thereby realizing dehumidifying and heating in the vehicle interior.

[0134] (b-2) Cooling dehumidifying and heating mode In the heat pump cycle 10 of the cooling dehumidifying and heating mode, the control device 60 sets the cooling expansion valve 14c in a throttled state with respect to the independent dehumidifying and heating mode.

[0135] For this reason, in the heat pump cycle 10 of the cooling dehumidifying and heating mode, the refrigerant discharged from the compressor 11 circulates in the same manner as in the independent dehumidifying and heating mode. At the same time, the refrigerant discharged from the compressor 11 is switched to a refrigerant circuit that circulates in the order of the water-cooled refrigerant heat exchanger 13, the dehumidifying passage 21b, the throttled cooling expansion valve 14c, the chiller 20, the accumulator 23, and the suction port of the compressor 11. That is, the indoor evaporator 18 and the chiller 20 are switched to a refrigerant circuit connected in parallel with respect to the refrigerant flow.

[0136] Also, in the high-temperature side heat medium circuit 30 in the cooling dehumidifying heating mode, similar to the single cooling mode, the high-temperature side heat medium pumped from the high-temperature side pump 31 circulates.

[0137] Also, in the low-temperature side heat medium circuit 40 in the cooling dehumidifying heating mode, similar to the cooling mode, the low-temperature side heat medium pumped from the low-temperature side pump 41 circulates.

[0138] Also, in the indoor air conditioner unit 50 in the cooling dehumidifying heating mode, similar to the single cooling mode, the control device 60 controls the rotation speed of the indoor blower 52, the opening degree of the air mix door 54, etc. Further, the control device 60 appropriately controls the operation of other controlled devices.

[0139] Therefore, in the heat pump cycle 10 in the cooling dehumidifying heating mode, a vapor compression refrigeration cycle is configured in which the water-cooled medium heat exchanger 13 functions as a condenser, and the indoor evaporator 18 and the chiller 20 function as evaporators. The suction side refrigerant pressure PS during the cooling dehumidifying heating mode is equivalent to that in the single cooling mode.

[0140] In the high-temperature side heat medium circuit 30 in the cooling dehumidifying heating mode, similar to the single cooling mode, the high-temperature side heat medium heated by the water-cooled medium heat exchanger 13 is pumped to the heater core 32.

[0141] In the low-temperature side heat medium circuit 40 in the cooling dehumidifying heating mode, similar to the cooling mode, the low-temperature side heat medium cooled by the chiller 20 flows into the cooling water passage 70a of the battery 70. Thereby, the battery 70 is cooled.

[0142] In the indoor air conditioner unit 50 in the cooling dehumidifying heating mode, similar to the single dehumidifying heating mode, the temperature-adjusted blown air is blown into the vehicle interior, thereby realizing dehumidifying heating in the vehicle interior.

[0143] (c) Heating mode The heating mode is an operation mode in which the interior of the vehicle is heated by blowing out heated supply air into the vehicle interior. The heating mode is likely to be selected when the outside air temperature Tam is relatively low or when the target blowing temperature TAO is relatively high.

[0144] The heating mode includes a sole outside air heat absorption heating mode in which the interior of the vehicle is heated using heat absorbed from the outside air without cooling the battery 70 as a heat source, a cooling outside air heat absorption heating mode in which the interior of the vehicle is heated using heat absorbed from the outside air while cooling the battery 70 as a heat source, and a waste heat recovery heating mode in which the interior of the vehicle is heated using the waste heat of the battery 70 as a heat source.

[0145] In the control program of the present embodiment, the sole outside air heat absorption heating mode, the cooling outside air heat absorption heating mode, and the waste heat recovery heating mode are switched based on the battery temperature TB, the supply air temperature TAV, etc.

[0146] (c-1) Sole outside air heat absorption heating mode In the heat pump cycle 10 of the sole outside air heat absorption heating mode, the control device 60 sets the heating expansion valve 14a in a throttled state, the cooling expansion valve 14b in a fully closed state, the cooling expansion valve 14c in a fully closed state, and the bypass side flow rate adjustment valve 14d in a fully closed state. Further, the control device 60 closes the dehumidification on-off valve 22a and opens the heating on-off valve 22b.

[0147] Therefore, in the heat pump cycle 10 of the sole outside air heat absorption heating mode, as shown by the solid line arrows in FIG. 4, the refrigerant discharged from the compressor 11 is switched to a refrigerant circuit in which the refrigerant circulates in the order of the water-cooled medium heat exchanger 13, the heating expansion valve 14a in a throttled state, the outdoor heat exchanger 15, the heating passage 21c, the accumulator 23, and the suction port of the compressor 11.

[0148] Also, in the high-temperature side heat medium circuit 30 of the sole outside air heat absorption heating mode, as shown by the broken line arrows in FIG. 4, the high-temperature side heat medium pumped from the high-temperature side pump 31 circulates in the same manner as in the sole cooling mode.

[0149] In addition, in the indoor air conditioner unit 50 in the independent outside air heat absorption heating mode, similar to the independent cooling mode, the control device 60 controls the rotation speed of the indoor blower 52, the opening degree of the air mix door 54, etc. Further, the control device 60 appropriately controls the operation of other controlled devices.

[0150] Therefore, in the heat pump cycle 10 in the independent outside air heat absorption heating mode, a vapor compression refrigeration cycle is configured in which the water-cooled refrigerant heat exchanger 13 functions as a condenser and the outdoor heat exchanger 15 functions as an evaporator.

[0151] Here, the refrigerant evaporation pressure in the outdoor heat exchanger 15 in the independent outside air heat absorption heating mode is adjusted so that the refrigerant decompressed by the heating expansion valve 14a can absorb heat from the outside air. More specifically, the saturation temperature of the refrigerant in the outdoor heat exchanger 15 is adjusted to be lower than the outside air temperature Tam.

[0152] Although the suction-side refrigerant pressure PS during the independent outside air heat absorption heating mode may decrease due to pressure loss, it is generally equivalent to the refrigerant evaporation pressure in the indoor evaporator 18. Since the heating mode is executed when the outside air temperature Tam is relatively low, the suction-side refrigerant pressure PS during the independent outside air heat absorption heating mode is likely to be lower than the suction-side refrigerant pressure PS during the independent cooling mode or the like.

[0153] In the high-temperature side heat medium circuit 30 in the independent outside air heat absorption heating mode, similar to the independent cooling mode, the high-temperature side heat medium heated by the water-cooled refrigerant heat exchanger 13 is pumped to the heater core 32.

[0154] In the indoor air conditioner unit 50 in the independent outside air heat absorption heating mode, the blown air sent from the indoor blower 52 passes through the indoor evaporator 18. The blown air that has passed through the indoor evaporator 18 is heated by exchanging heat with the high-temperature side heat medium in the heater core 32 according to the opening degree of the air mix door 54. Then, the blown air whose temperature is adjusted to approach the target blow-out temperature TAO is blown into the vehicle interior. Thereby, heating of the vehicle interior is realized.

[0155] (c-2) Cooling outside air heat absorption heating mode In the heat pump cycle 10 of the cooling outside air heat absorption heating mode, for the single outside air heat absorption heating mode, the control device 60 sets the cooling expansion valve 14c to a throttled state. Further, the control device 60 opens the dehumidification on-off valve 22a.

[0156] Therefore, in the heat pump cycle 10 of the cooling outside air heat absorption heating mode, the refrigerant discharged from the compressor 11 circulates in the same manner as in the single outside air heat absorption heating mode. At the same time, the refrigerant discharged from the compressor 11 is switched to a refrigerant circuit that circulates in the order of the water-cooled medium heat exchanger 13, the dehumidification passage 21b, the cooling expansion valve 14c in a throttled state, the chiller 20, the accumulator 23, and the suction port of the compressor 11. That is, the outdoor heat exchanger 15 and the chiller 20 are switched to a refrigerant circuit connected in parallel with respect to the flow of the refrigerant.

[0157] Further, in the high-temperature side heat medium circuit 30 of the cooling outside air heat absorption heating mode, the high-temperature side heat medium pumped from the high-temperature side pump 31 circulates in the same manner as in the single cooling mode.

[0158] Further, in the low-temperature side heat medium circuit 40 of the cooling outside air heat absorption heating mode, the low-temperature side heat medium pumped from the low-temperature side pump 41 circulates in the same manner as in the cooling and cooling mode.

[0159] Further, in the indoor air conditioner unit 50 of the cooling outside air heat absorption heating mode, the control device 60 controls the rotation speed of the indoor blower 52, the opening degree of the air mix door 54, etc. in the same manner as in the single cooling mode. Further, the control device 60 appropriately controls the operation of other controlled devices.

[0160] Therefore, in the heat pump cycle 10 of the cooling outside air heat absorption heating mode, a vapor compression refrigeration cycle is configured in which the water-cooled medium heat exchanger 13 functions as a condenser, and the outdoor heat exchanger 15 and the chiller 20 function as evaporators. The suction side refrigerant pressure PS during the cooling outside air heat absorption heating mode is equivalent to that in the single outside air heat absorption heating mode.

[0161] In the high-temperature side heat medium circuit 30 in the cooling outside air heat absorption heating mode, similar to the single cooling mode, the high-temperature side heat medium heated by the water-cooled medium heat exchanger 13 is pumped to the heater core 32.

[0162] In the low-temperature side heat medium circuit 40 in the cooling outside air heat absorption heating mode, similar to the cooling cooling mode, the low-temperature side heat medium cooled by the chiller 20 flows into the cooling water passage 70a of the battery 70. Thereby, the battery 70 is cooled.

[0163] In the indoor air conditioner unit 50 in the cooling outside air heat absorption heating mode, similar to the single outside air heat absorption heating mode, the temperature-adjusted blown air is blown into the vehicle interior, thereby realizing heating in the vehicle interior.

[0164] (c-3) Waste heat recovery heating mode In the heat pump cycle 10 in the waste heat recovery heating mode, the control device 60 fully closes the heating expansion valve 14a, fully closes the cooling expansion valve 14b, sets the cooling expansion valve 14c in a throttled state, and fully closes the bypass side flow rate adjustment valve 14d. Further, the control device 60 opens the dehumidification on-off valve 22a and closes the heating on-off valve 22b.

[0165] Therefore, in the heat pump cycle 10 in the waste heat recovery heating mode, as shown by the solid line arrow in FIG. 5, the refrigerant discharged from the compressor 11 is switched to a refrigerant circuit that circulates in the order of the water-cooled medium heat exchanger 13, the dehumidification passage 21b, the cooling expansion valve 14c in a throttled state, the chiller 20, the accumulator 23, and the suction port of the compressor 11.

[0166] Also, in the high-temperature side heat medium circuit 30 in the waste heat recovery heating mode, as shown by the broken line arrow in FIG. 5, similar to the single cooling mode, the high-temperature side heat medium pumped from the high-temperature side pump 31 circulates.

[0167] Also, in the low-temperature side heat medium circuit 40 in the waste heat recovery heating mode, as shown by the broken line arrow in FIG. 5, similar to the cooling cooling mode, the low-temperature side heat medium pumped from the low-temperature side pump 41 circulates.

[0168] In addition, in the indoor air conditioner unit 50 in the waste heat recovery heating mode, similar to the single cooling mode, the control device 60 controls the rotation speed of the indoor blower 52, the opening degree of the air mix door 54, etc. Further, the control device 60 appropriately controls the operation of other controlled devices.

[0169] Therefore, in the heat pump cycle 10 in the waste heat recovery heating mode, a vapor compression refrigeration cycle is configured in which the water-cooled refrigerant heat exchanger 13 functions as a condenser and the chiller 20 functions as an evaporator.

[0170] Here, the refrigerant evaporation pressure in the chiller 20 in the waste heat recovery heating mode is adjusted so that the battery 70 can be appropriately cooled. In the present embodiment, the saturation temperature of the refrigerant in the chiller 20 is adjusted to be higher than the outside air temperature Tam.

[0171] Although the suction-side refrigerant pressure PS in the waste heat recovery heating mode may decrease due to pressure loss, it is generally equivalent to the refrigerant evaporation pressure in the chiller 20. For this reason, the refrigerant pressure in the accumulator 23 in the waste heat recovery heating mode is more likely to be higher than the refrigerant pressure in the accumulator 23 in the single outside air heat absorption heating mode or the like.

[0172] In the high-temperature side heat medium circuit 30 in the waste heat recovery heating mode, similar to the single cooling mode, the high-temperature side heat medium heated by the water-cooled refrigerant heat exchanger 13 is pumped to the heater core 32.

[0173] In the low-temperature side heat medium circuit 40 in the waste heat recovery heating mode, similar to the cooling and cooling mode, the low-temperature side heat medium cooled by the chiller 20 flows into the cooling water passage 70a of the battery 70. Thereby, the battery 70 is cooled.

[0174] In the indoor air conditioner unit 50 in the waste heat recovery heating mode, similar to the single outside air heat absorption heating mode, the temperature-adjusted blown air is blown into the vehicle interior, thereby realizing heating in the vehicle interior.

[0175] (d) Hot gas heating mode The hot gas heating mode is an operation mode for heating the interior of the vehicle. The hot gas heating mode is selected when the outside air temperature Tam is extremely low (less than -10°C in this embodiment).

[0176] In the heat pump cycle 10 of the hot gas heating mode, the control device 60 fully closes the heating expansion valve 14a, fully closes the cooling expansion valve 14b, sets the cooling expansion valve 14c in a throttled state, and sets the bypass side flow rate adjustment valve 14d in a throttled state. Further, the control device 60 opens the dehumidification on-off valve 22a and closes the heating on-off valve 22b.

[0177] Therefore, in the heat pump cycle 10 of the hot gas heating mode, as shown by the solid line arrows in FIG. 6, the refrigerant discharged from the compressor 11 circulates in the order of the first three-way joint 12a, the water-cooled heat exchanger 13, the dehumidification passage 21b, the throttled cooling expansion valve 14c, the sixth three-way joint 12f, the chiller 20, the accumulator 23, and the suction port of the compressor 11. At the same time, the refrigerant discharged from the compressor 11 is switched to a refrigerant circuit that circulates in the order of the first three-way joint 12a, the throttled bypass side flow rate adjustment valve 14d arranged in the bypass passage 21a, the sixth three-way joint 12f, the chiller 20, the accumulator 23, and the suction port of the compressor 11.

[0178] Also, in the high-temperature side heat medium circuit 30 of the hot gas heating mode, as shown by the broken line arrows in FIG. 6, the high-temperature side heat medium pumped from the high-temperature side pump 31 circulates in the same manner as in the single cooling mode.

[0179] Also, in the indoor air conditioner unit 50 in the waste heat recovery heating mode, the control device 60 controls the rotation speed of the indoor blower 52, the opening degree of the air mix door 54, etc. in the same manner as in the single cooling mode. Further, the control device 60 appropriately controls the operation of other controlled devices.

[0180] Therefore, in the heat pump cycle 10 in the hot gas heating mode, the refrigerant flow discharged from the compressor 11 is branched at the first three-way joint 12a. One of the refrigerants branched at the first three-way joint 12a flows into the water-cooled heat exchanger 13 and releases heat to the high-temperature side heat medium. Thereby, the high-temperature side heat medium is heated.

[0181] The refrigerant flowing out from the water-cooled heat exchanger 13 flows into the cooling expansion valve 14c through the dehumidification passage 21b and is depressurized. The refrigerant with a relatively low enthalpy flowing out from the cooling expansion valve 14c flows into the other inlet of the sixth three-way joint 12f.

[0182] On the other hand, the other refrigerant branched at the first three-way joint 12a flows into the bypass passage 21a. The refrigerant flowing into the bypass passage 21a is adjusted in flow rate by the bypass side flow rate adjustment valve 14d and is depressurized. The refrigerant with a relatively high enthalpy depressurized by the bypass side flow rate adjustment valve 14d flows into one inlet of the sixth three-way joint 12f.

[0183] The refrigerant flow flowing out from the bypass side flow rate adjustment valve 14d and the refrigerant flow flowing out from the cooling expansion valve 14c merge and are mixed at the sixth three-way joint 12f. The refrigerant flowing out from the sixth three-way joint 12f flows into the chiller 20 and is further mixed homogeneously. The refrigerant flowing out from the refrigerant passage of the chiller 20 flows into the accumulator 23. The gaseous phase refrigerant separated by the accumulator 23 is sucked into the compressor 11 and compressed again.

[0184] In the high-temperature side heat medium circuit 30 in the hot gas heating mode, similar to the single cooling mode, the high-temperature side heat medium heated by the water-cooled heat exchanger 13 is pumped to the heater core 32.

[0185] In the indoor air conditioning unit 50 in the hot gas heating mode, similar to the single outside air heat absorption heating mode, the temperature-adjusted blown air is blown into the vehicle interior, thereby realizing heating in the vehicle interior.

[0186] Here, the hot gas heating mode is an operation mode selected when the outside air temperature Tam is extremely low. Therefore, when the refrigerant flowing out of the water-cooled refrigerant heat exchanger 13 is made to flow into the outdoor heat exchanger 15, even if it is decompressed by the heating expansion valve 14a, there is a possibility that the refrigerant will dissipate heat to the outside air in the outdoor heat exchanger 15.

[0187] If the refrigerant dissipates heat to the outside air in the outdoor heat exchanger 15, the amount of heat dissipated by the refrigerant to the high-temperature side heat medium in the water-cooled refrigerant heat exchanger 13 will decrease, so the heating capacity of the blown air in the heating section will decrease.

[0188] Therefore, in the hot gas heating mode, the refrigerant circuit of the heat pump cycle 10 is switched to a refrigerant circuit in which the refrigerant flowing out of the water-cooled refrigerant heat exchanger 13 does not flow into the outdoor heat exchanger 15. According to this, the heat generated by the work of the compressor 11 can be effectively used to heat the blown air, and a decrease in the heating capacity in the heating section can be suppressed.

[0189] On the other hand, in the refrigerant circuit of the heat pump cycle 10 in the hot gas heating mode, the refrigerant cannot absorb heat from the outside air side. Therefore, in order to improve the heating capacity of the blown air in the heating section, means for increasing the discharge flow rate of the compressor 11 is effective. Furthermore, in order to increase the discharge flow rate of the compressor 11, it is necessary to increase the suction side refrigerant pressure PS to increase the suction density of the refrigerant sucked into the compressor 11.

[0190] Therefore, in the hot gas heating mode, the suction side refrigerant pressure PS is adjusted to be higher than in all heating modes (that is, in the single outside air heat absorption heating mode, the cooling outside air heat absorption heating mode, and the waste heat recovery heating mode). More specifically, in this embodiment, the suction side refrigerant saturation temperature is adjusted to be about 20°C. The adjustment of the suction side refrigerant pressure PS is performed by controlling the refrigerant discharge capacity of the compressor 11, the throttle opening degree of the cooling expansion valve 14c, and the throttle opening degree of the bypass side flow rate adjustment valve 14d.

[0191] As described above, in the vehicle air conditioner 1 of the present embodiment, by switching the operation mode, it is possible to perform comfortable air conditioning in the vehicle interior and appropriate temperature adjustment of the battery 70 which is an in-vehicle device.

[0192] By the way, in the vehicle air conditioner 1 of the present embodiment, as described above, when the operation mode is switched, the suction-side refrigerant pressure PS may change. In other words, in the vehicle air conditioner 1 of the present embodiment, when the operation mode is switched, the refrigerant pressure in the accumulator 23 may change rapidly.

[0193] When the operation mode is switched and the refrigerant pressure in the accumulator 23 drops rapidly, a so-called flashing phenomenon may occur in which the liquid-phase refrigerant in the accumulator 23 boils rapidly, and a so-called foaming phenomenon may occur in which the liquid-phase refrigerant is lifted up. When such a foaming phenomenon occurs, the compressor 11 sucks in a refrigerant with a low dryness, which has an adverse effect on the durability life of the compressor 11 due to liquid compression.

[0194] Therefore, in the vehicle air conditioner 1 of the present embodiment, when the operation mode is switched, liquid amount reduction control is performed to reduce the amount of liquid-phase refrigerant in the accumulator 23.

[0195] The liquid amount reduction control is executed when the operation mode is switched from the first operation mode to the second operation mode, where a predetermined operation mode is defined as the first operation mode and an operation mode in which the suction-side refrigerant pressure PS is lower than that in the first operation mode is defined as the second operation mode. The second operation mode is not limited to an operation mode in which the suction-side refrigerant pressure PS is always lower than that in the first operation mode, and includes an operation mode in which the suction-side refrigerant pressure PS can be lower than that in the first operation mode.

[0196] In the liquid amount reduction control, the amount of liquid-phase refrigerant stored in the accumulator 23 is reduced by causing the refrigerant in the heat pump cycle 10 to flow into the recovery flow path 24. The recovery flow path 24 is a refrigerant flow path in which the refrigerant does not flow during the first operation mode and is formed so that the refrigerant can flow in.

[0197] By performing liquid volume reduction control, the refrigerant recovery passage 24 desirably has a volume equal to or greater than that of the accumulator 23 so that the amount of liquid-phase refrigerant stored in the accumulator 23 can be reliably reduced. Therefore, the refrigerant recovery passage 24 of the present embodiment is formed by a refrigerant passage including a component device having a relatively large internal volume (specifically, a heat exchanger).

[0198] Furthermore, the refrigerant recovery passage 24 of the present embodiment is formed so as to be able to connect a portion through which the high-pressure side refrigerant flows and a portion through which the low-pressure side refrigerant flows in the first operation mode.

[0199] In the control program of the present embodiment, the operation mode is switched based on the outside air temperature Tam and the target blow-out temperature TAO. Therefore, in the vehicle air conditioner 1 of the present embodiment, the following combinations can be considered as the operation modes corresponding to the first operation mode and the second operation mode.

[0200] For example, when the hot gas heating mode is defined as the first operation mode, the single outside air heat absorption heating mode, the cooling outside air heat absorption heating mode, and the waste heat recovery heating mode can be defined as the second operation mode. When the hot gas heating mode is defined as the first operation mode, the refrigerant recovery passage 24 is formed by a refrigerant passage that extends from one outlet of the second three-way joint 12b, through the heating expansion valve 14a, the outdoor heat exchanger 15, and the heating passage 21c, and reaches the fourth three-way joint 12d, as shown in FIG. 6.

[0201] Also, when the waste heat recovery heating mode is defined as the first operation mode, the single outside air heat absorption heating mode or the cooling outside air heat absorption heating mode can be defined as the second operation mode. When the waste heat recovery heating mode is defined as the first operation mode, the refrigerant recovery passage 24 is formed by a refrigerant passage that extends from one outlet of the second three-way joint 12b, through the heating expansion valve 14a, the outdoor heat exchanger 15, and the heating passage 21c, and reaches the fourth three-way joint 12d, as shown in FIG. 5.

[0202] When the independent dehumidification heating mode or the cooling dehumidification heating mode is defined as the first operation mode, the independent outdoor air heat absorption heating mode or the cooling outdoor air heat absorption heating mode can be defined as the second operation mode. When the independent dehumidification heating mode or the cooling dehumidification heating mode is defined as the first operation mode, the recovery flow path 24 is formed by a refrigerant flow path that extends from one outlet of the second three-way joint 12b to the fifth three-way joint 12e via the heating expansion valve 14a, the outdoor heat exchanger 15, the heating passage 21c, and the fourth three-way joint 12d as shown in FIG. 3.

[0203] In the liquid amount reduction control, as shown in the time charts of FIGS. 7 and 8, the operation of each component device is controlled. The liquid amount reduction control is executed when the control program determines the switching from the first operation mode to the second operation mode. First, the time chart of FIG. 7 shows an example in which the hot gas heating mode is defined as the first operation mode and the independent outdoor air heat absorption heating mode is defined as the second operation mode.

[0204] In the liquid amount reduction control of FIG. 7, when the switching from the first operation mode to the second operation mode is determined, the heating expansion valve 14a is changed from the fully closed state to the throttling state. That is, in the liquid amount reduction control, the heating expansion valve 14a is opened. At this time, the opening degree of the heating expansion valve 14a is set to a minute opening degree that does not affect the high and low pressure balance of the heat pump cycle 10 in the hot gas heating mode.

[0205] As a result, in the liquid amount reduction control, refrigerant flows into the recovery flow path 24. That is, a part of the high-pressure side refrigerant flowing out from the water-cooled refrigerant heat exchanger 13 flows into the outdoor heat exchanger 15 via the heating expansion valve 14a. Since the heating mode is executed when the outdoor air temperature Tam is relatively low, the refrigerant flowing into the outdoor heat exchanger 15 condenses and is stored in the outdoor heat exchanger 15. As a result, the amount of liquid-phase refrigerant in the accumulator 23 is reduced.

[0206] After that, wait for the elapse of a predetermined recovery time Tmc and then end the liquid volume reduction control. Then, after the end of the liquid volume reduction control, switch to the independent outside air heat absorption heating mode. The recovery time Tmc in the present embodiment is set to a time interval (specifically, 10 seconds) capable of appropriately reducing the liquid-phase refrigerant amount in the accumulator 23.

[0207] Also, when the hot gas heating mode is defined as the first operation mode and the cooling outside air heat absorption heating mode is defined as the second operation mode, the same liquid volume reduction control as in FIG. 7 may be performed. In this case, when the independent outside air heat absorption heating mode is defined as the second operation mode, after the end of the liquid volume reduction control, the cooling expansion valve 14c may be throttled and the dehumidification on-off valve 22a may be opened.

[0208] Also, when the hot gas heating mode is defined as the first operation mode and the waste heat recovery heating mode is defined as the second operation mode, the same liquid volume reduction control as in FIG. 7 may be executed. In this case, when the independent outside air heat absorption heating mode is defined as the second operation mode, after the end of the liquid volume reduction control, the heating expansion valve 14a may be fully closed, the cooling expansion valve 14c may be throttled, and the dehumidification on-off valve 22a may be opened.

[0209] Also, the time chart in FIG. 8 shows an example in which the waste heat recovery heating mode is defined as the first operation mode and the independent outside air heat absorption heating mode is defined as the second operation mode. Also in the liquid volume reduction control in FIG. 8, when the switching from the first operation mode to the second operation mode is determined, the heating expansion valve 14a is changed from the fully closed state to the throttled state. Thereby, similar to the liquid volume reduction control in FIG. 7, the liquid-phase refrigerant amount in the accumulator 23 can be reduced.

[0210] Also, when the waste heat recovery heating mode is defined as the first operation mode and the cooling outside air heat absorption heating mode is defined as the second operation mode, the same liquid volume reduction control as in FIG. 8 may be performed. In this case, when the independent outside air heat absorption heating mode is defined as the second operation mode, after the elapse of the recovery time Tmc, the cooling expansion valve 14c may be throttled and the dehumidification on-off valve 22a may be opened.

[0211] Also, when the single dehumidification heating mode or the cooling dehumidification heating mode is defined as the first operation mode, and the single outdoor air heat absorption heating mode or the cooling outdoor air heat absorption heating mode is defined as the second operation mode, the same liquid amount reduction control may be implemented. That is, in the liquid amount reduction control, the heating expansion valve 14a may be changed from the fully closed state to the throttling state.

[0212] According to the vehicle air conditioner 1 of the present embodiment, when switching from the first operation mode to the second operation mode, liquid amount reduction control is performed. Thereby, the amount of liquid-phase refrigerant in the accumulator 23 can be reduced. Therefore, even when the suction-side refrigerant pressure PS drops when switching from the first operation mode to the second operation mode, the forming phenomenon is less likely to occur, and liquid compression of the compressor 11 can be suppressed.

[0213] That is, even in a heat pump cycle device such as the vehicle air conditioner 1 of the present embodiment, which is provided with an accumulator 23 and is configured to be able to switch the operation mode, the compressor 11 can be appropriately protected. Furthermore, in the liquid amount reduction control, since only the surplus refrigerant in the cycle is moved from the accumulator 23 into the outdoor heat exchanger 15, the heating ability of the blown air in the heating section does not decrease during the execution of the liquid amount reduction control.

[0214] Also, in the vehicle air conditioner 1 of the present embodiment, the recovery flow path 24 is formed so as to be able to connect a portion where the high-pressure side refrigerant flows and a portion where the low-pressure side refrigerant flows during the first operation mode. According to this, by allowing the refrigerant to flow in from the high-pressure side during the liquid amount reduction control, the refrigerant can be made to flow into the recovery flow path 24 in a short time. Therefore, the amount of liquid-phase refrigerant in the accumulator 23 can be reduced in a short time.

[0215] In addition, in the vehicle air conditioner 1 of the present embodiment, when switching from the hot gas heating mode to the independent outside air heat absorption heating mode or the cooling outside air heat absorption heating mode, liquid amount reduction control is performed. Also, when switching from the waste heat recovery heating mode to the independent outside air heat absorption heating mode or the cooling outside air heat absorption heating mode, liquid amount reduction control is performed. Further, when switching from the independent dehumidifying heating mode or the cooling dehumidifying heating mode to the independent outside air heat absorption heating mode or the cooling outside air heat absorption heating mode, liquid amount reduction control is performed.

[0216] In these operation mode switches, the recovery flow path 24 is formed by the part through which the refrigerant flows in the second operation mode. Therefore, by switching to the second operation mode, the refrigerant stored in the outdoor heat exchanger 15 can be returned to the accumulator 23 again. As a result, after switching to the second operation mode, it is possible to avoid a refrigerant shortage in the heat pump cycle 10.

[0217] In addition, in the vehicle air conditioner 1 of the present embodiment, since the heating expansion valve 14a and the outdoor heat exchanger 15 form the recovery flow path 24, in the liquid amount reduction control, the liquid phase refrigerant amount in the accumulator 23 can be reduced by a simple control of opening the heating expansion valve 14a.

[0218] (Second Embodiment) In the present embodiment, as shown in the overall configuration diagram of FIG. 9, an example in which the first three-way joint 12a, the sixth three-way joint 12f, the bypass passage 21a, and the bypass side flow rate adjustment valve 14d of the heat pump cycle 10 are abolished with respect to the first embodiment will be described. The configuration of the other vehicle air conditioner 1 is the same as that of the first embodiment.

[0219] In the vehicle air conditioner 1 of the present embodiment, the operations in (a) the cooling mode, (b) the dehumidifying heating mode, and (c) the heating mode described in the first embodiment can be executed.

[0220] Therefore, in the vehicle air conditioner 1 of the present embodiment, the waste heat recovery heating mode is defined as the first operation mode, and the independent outside air heat absorption heating mode or the cooling outside air heat absorption heating mode is defined as the second operation mode. Then, by performing the liquid amount reduction control when switching from the first operation mode to the second operation mode, the same effects as those of the first embodiment can be obtained.

[0221] Further, the independent dehumidification heating mode or the cooling dehumidification heating mode is defined as the first operation mode, and the independent outside air heat absorption heating mode or the cooling outside air heat absorption heating mode is defined as the second operation mode. Then, by performing the liquid amount reduction control when switching from the first operation mode to the second operation mode, the same effects as those of the first embodiment can be obtained.

[0222] That is, in the vehicle air conditioner 1 of the present embodiment, even in a heat pump cycle device provided with an accumulator 23 and configured to be able to switch the operation mode, the compressor 11 can be appropriately protected.

[0223] (Third Embodiment) In the present embodiment, as shown in the overall configuration diagram of FIG. 10, an example in which a third check valve 16c is added to the first embodiment will be described.

[0224] The third check valve 16c is disposed in the heating passage 21c. The third check valve 16c allows the refrigerant to flow from the outlet side of the heating on-off valve 22b to one inlet side of the fourth three-way joint 12d, and prohibits the refrigerant from flowing from the fourth three-way joint 12d side to the outlet side of the heating on-off valve 22b. The configuration of the other heat pump cycle 10 is the same as that of the first embodiment.

[0225] Therefore, in the vehicle air conditioner 1 of the present embodiment, it operates in exactly the same manner as in the first embodiment. As a result, the same effects as those of the first embodiment can be obtained. That is, even in a heat pump cycle device provided with an accumulator 23 and configured to be able to switch the operation mode, the compressor 11 can be appropriately protected.

[0226] Furthermore, in the vehicle air conditioner 1 of the present embodiment, since the third check valve 16c is adopted, the heating on-off valve 22b does not have to have reverse sealing performance. That is, the heating on-off valve 22b does not have to have a function of prohibiting the refrigerant from flowing from one inlet side of the fourth three-way joint 12d to the other outlet side of the third three-way joint 12c. Therefore, the heating on-off valve 22b may be opened in the hot gas heating mode.

[0227] (Fourth Embodiment) In the present embodiment, an example in which the heat pump cycle device according to the present invention is applied to the vehicle air conditioner 1a shown in FIG. 11 will be described. The vehicle air conditioner 1a is a heat pump cycle device that performs air conditioning in the vehicle interior and temperature adjustment of in-vehicle devices, similar to the vehicle air conditioner 1 described in the first embodiment. The vehicle air conditioner 1a includes a heat pump cycle 10a, a heat medium circuit 30a, an interior air conditioning unit 50, a control device 60, and the like.

[0228] The heat pump cycle 10a of the present embodiment is a vapor compression refrigeration cycle that adjusts the temperature of the blown air sent into the vehicle interior and the heat medium circulating in the heat medium circuit 30a. The heat pump cycle 10a is configured to be able to switch the circuit configuration of the refrigerant circuit according to the operation mode of the vehicle air conditioner 1a.

[0229] The heat pump cycle 10a has the second three-way joint 12b, the third three-way joint 12c, the fourth three-way joint 12d, the heating expansion valve 14a, the outdoor heat exchanger 15, the dehumidification passage 21b, the heating passage 21c, the dehumidification on-off valve 22a, the heating on-off valve 22b, etc. abolished with respect to the heat pump cycle 10 described in the first embodiment.

[0230] At the outlet of the refrigerant passage of the water-cooled medium heat exchanger 13 of the heat pump cycle 10a, the inlet side of the seventh three-way joint 12g is connected. To one outlet of the seventh three-way joint 12g, the inlet side of the cooling expansion valve 14b is connected. To the other outlet of the seventh three-way joint 12g, the inlet side of the cooling expansion valve 14c is connected. The configuration of the other heat pump cycle 10a is the same as that of the heat pump cycle 10 described in the first embodiment.

[0231] Next, the heat medium circuit 30a will be described. The heat medium circuit 30a is a heat medium circulation circuit that circulates the heat medium. The heat medium circuit 30a is configured to be able to switch the circuit configuration according to the operation mode of the vehicle air conditioner 1a. In the present embodiment, an ethylene glycol aqueous solution is adopted as the heat medium.

[0232] In the heat medium circuit 30a, there are arranged a heat medium passage of the water-cooled medium heat exchanger 13, a high-temperature side pump 31, a heater core 32, a high-temperature side three-way valve 33, a radiator 34, a heat medium passage of the chiller 20, a low-temperature side pump 41, a low-temperature side three-way valve 43, a cooling water passage 70a of the battery 70, and the like.

[0233] To the discharge port of the high-temperature side pump 31 of the heat medium circuit 30a, the inlet side of the heat medium passage of the water-cooled medium heat exchanger 13 is connected. To the outlet of the heat medium passage of the water-cooled medium heat exchanger 13, the inlet side of the high-temperature side three-way valve 33 is connected. To one outlet of the high-temperature side three-way valve 33, one inlet side of the first heat medium three-way joint 35a is connected. To the other outlet of the high-temperature side three-way valve 33, the heat medium inlet side of the heater core 32 is connected.

[0234] The high-temperature side three-way valve 33 is a three-mode flow rate adjustment valve capable of continuously adjusting the flow rate ratio between the flow rate of the heat medium flowing out from the heat medium passage of the water-cooled medium heat exchanger 13 and flowing into the radiator 34 via the first heat medium three-way joint 35a and the flow rate of the heat medium flowing into the heater core 32. The operation of the high-temperature side three-way valve 33 is controlled by a control signal output from the control device 60.

[0235] The high-temperature three-way valve 33 can allow the entire flow rate of the heat medium flowing out from the heat medium passage of the water-cooled medium heat exchanger 13 to flow into the radiator 34. Further, the high-temperature three-way valve 33 can allow the entire flow rate of the heat medium flowing out from the heat medium passage of the water-cooled medium heat exchanger 13 to flow into the heater core 32. Therefore, the high-temperature three-way valve 33 is an operation mode switching unit that switches the operation mode by switching the circuit configuration.

[0236] The first heat medium three-way joint 35a is a joint part having three inlets / outlets communicating with each other, similar to the first three-way joint 12a etc. described in the first embodiment. Further, as will be described later, the heat medium circuit 30a includes second to fourth heat medium three-way joints 35b to 35d. The basic configuration of the second to fourth heat medium three-way joints 35b to 35d is the same as that of the first heat medium three-way joint 35a.

[0237] The outlet side of the first heat medium three-way joint 35a is connected to the heat medium inlet side of the radiator 34. The radiator 34 is a water-air heat exchange unit that exchanges heat between the heat medium flowing out from the first heat medium three-way joint 35a and the outside air. The radiator 34 is arranged on the front side of the drive device chamber together with the outdoor heat exchanger 15 of the heat pump cycle 10a.

[0238] When a heat medium at a temperature higher than the outside air temperature Tam flows into the radiator 34, it becomes a heat medium heat dissipation unit that dissipates the heat of the heat medium to the outside air. Further, when a heat medium at a temperature lower than the outside air temperature Tam flows into the radiator 34, it becomes a heat medium heat absorption unit that absorbs the outside air side heat of the outside air into the heat medium.

[0239] The heat medium outlet of the radiator 34 is connected to the inlet side of the second heat medium three-way joint 35b. One outlet side of the second heat medium three-way joint 35b is connected to one inlet side of the third heat medium three-way joint 35c. The other outlet side of the second heat medium three-way joint 35b is connected to one inlet side of the fourth heat medium three-way joint 35d.

[0240] On the heat medium outlet of the heater core 32, the other inlet side of the third heat medium three-way joint 35c is connected. To the outlet of the third heat medium three-way joint 35c, the suction inlet side of the high-temperature side pump 31 is connected. Therefore, in the heat medium circuit 30a, by switching the circuit configuration so that the high-temperature side three-way valve 33 allows the heat medium flowing out from the heat medium passage of the water-cooled medium heat exchanger 13 to flow into the heater core 32, a heating section similar to that of the first embodiment can be formed.

[0241] To the discharge port of the low-temperature side pump 41 in the heat medium circuit 30a, the inlet side of the heat medium passage of the chiller 20 is connected. To the outlet of the heat medium passage of the chiller 20, the inlet side of the low-temperature side three-way valve 43 is connected. To one outlet of the low-temperature side three-way valve 43, the inlet side of the cooling water passage 70a of the battery 70 is connected. To the other outlet of the low-temperature side three-way valve 43, the other inlet side of the first heat medium three-way joint 35a is connected.

[0242] The low-temperature side three-way valve 43 is a three-mode flow rate adjustment valve capable of continuously adjusting the flow rate ratio between the flow rate of the heat medium flowing into the cooling water passage 70a of the battery 70 and the flow rate of the heat medium flowing out from the heat medium passage of the chiller 20 and flowing into the radiator 34 via the first heat medium three-way joint 35a. The basic configuration of the low-temperature side three-way valve 43 is the same as that of the high-temperature side three-way valve 33.

[0243] The low-temperature side three-way valve 43 can make the total flow rate of the heat medium flowing out from the heat medium passage of the chiller 20 flow into the cooling water passage 70a of the battery 70. Also, the low-temperature side three-way valve 43 can make the total flow rate of the heat medium flowing out from the heat medium passage of the chiller 20 flow into the radiator 34. Therefore, the low-temperature side three-way valve 43 is an operation mode switching section that switches the operation mode by switching the circuit configuration.

[0244] To the outlet of the cooling water passage 70a of the battery 70, the one inlet side of the fourth heat medium three-way joint 35d is connected. To the outlet of the fourth heat medium three-way joint 35d, the suction inlet side of the low-temperature side pump 41 is connected.

[0245] Therefore, in the heat medium circuit 30a, the low-temperature three-way valve 43 allows the heat medium flowing out of the heat medium passage of the chiller 20 to flow into the cooling water passage 70a of the battery 70, enabling the heat medium to absorb the equipment-side heat generated by the battery 70. Further, the low-temperature three-way valve 43 allows the heat medium flowing out of the heat medium passage of the chiller 20 to flow into the radiator 34, enabling the heat medium to absorb the outside-air-side heat possessed by the outside air.

[0246] Accordingly, the chiller 20 of the present embodiment serves as a common heat absorption unit that causes the refrigerant to absorb at least one of the equipment-side heat and the outside-air-side heat via the heat medium. Furthermore, the cooling expansion valve 14c of the present embodiment serves as a common pressure reduction unit that reduces the pressure of the refrigerant flowing into the chiller 20. Also, the low-temperature three-way valve 43 serves as a heat absorption ratio adjustment unit that adjusts the ratio between the outside-air-side heat and the equipment-side heat in the heat that causes the refrigerant to absorb heat in the chiller 20.

[0247] The configuration of the other vehicle air conditioner 1a is the same as that of the vehicle air conditioner 1 described in the first embodiment.

[0248] Next, the operation of the vehicle air conditioner 1a of the present embodiment with the above configuration will be described. In the vehicle air conditioner 1a, similar to the vehicle air conditioner 1 described in the first embodiment, various operation modes are switched to perform air conditioning in the vehicle interior and temperature adjustment of the battery 70. The detailed operation of each operation mode will be described below.

[0249] (a-1) Single cooling mode In the heat pump cycle 10a in the single cooling mode, the control device 60 sets the cooling expansion valve 14b to a throttled state, the cooling expansion valve 14c to a fully closed state, and the bypass-side flow rate adjustment valve 14d to a fully closed state.

[0250] Therefore, in the heat pump cycle 10a in the single cooling mode, the refrigerant discharged from the compressor 11 is switched to a refrigerant circuit that circulates in the order of the water-cooled heat exchanger 13, the throttled cooling expansion valve 14b, the indoor evaporator 18, the accumulator 23, and the suction port of the compressor 11.

[0251] In the heat medium circuit 30a in the single cooling mode, the control device 60 operates the high-temperature side pump 31 so as to exhibit a predetermined reference pumping capacity. Further, the control device 60 controls the operation of the high-temperature side three-way valve 33 so that the high-temperature side heat medium temperature TWH detected by the high-temperature side heat medium temperature sensor 63a approaches a predetermined reference high-temperature side heat medium temperature KTWH.

[0252] Therefore, in the heat medium circuit 30a in the single cooling mode, the heat medium pumped from the high-temperature side pump 31 circulates in the order of the water-cooled medium heat exchanger 13, the heater core 32, and the suction port of the high-temperature side pump 31. At the same time, the low-temperature side heat medium pumped from the high-temperature side pump 31 is switched to a circuit that circulates in the order of the water-cooled medium heat exchanger 13, the radiator 34, and the suction port of the high-temperature side pump 31.

[0253] In the indoor air-conditioning unit 50 in the single cooling mode, the control device 60 controls the rotation speed of the indoor blower 52, the opening degree of the air mix door 54, etc., in the same manner as in the first embodiment. Further, the control device 60 appropriately controls the operation of other controlled devices.

[0254] Therefore, in the heat pump cycle 10a in the single cooling mode, a vapor compression refrigeration cycle is configured in which the water-cooled medium heat exchanger 13 functions as a condenser that dissipates and condenses the refrigerant, and the indoor evaporator 18 functions as an evaporator that evaporates the refrigerant. The suction-side refrigerant pressure PS in the single cooling mode is equivalent to that in the single cooling mode of the first embodiment.

[0255] In the heat medium circuit 30a in the single cooling mode, the heat medium flowing into the heat medium passage of the water-cooled medium heat exchanger 13 exchanges heat with the refrigerant discharged from the compressor 11 and is heated. The heat medium heated by the water-cooled medium heat exchanger 13 flows into the heater core 32 and the radiator 34 according to the operation of the high-temperature side three-way valve 33.

[0256] The heat medium flowing into the heater core 32 dissipates heat to the blown air. As a result, the blown air is heated. The heat medium flowing into the radiator 34 dissipates heat to the outside air and is cooled. The heat medium flowing out of the heater core 32 and the heat medium flowing out of the radiator 34 are sucked into the high-temperature side pump 31 and pumped into the heat medium passage of the water-cooled medium heat exchanger 13.

[0257] In the indoor air-conditioning unit 50 in the single cooling mode, similar to the first embodiment, the temperature-adjusted blown air is blown into the vehicle interior, thereby realizing cooling in the vehicle interior.

[0258] (a-2) Cooling and refrigeration mode In the heat pump cycle 10a in the cooling and refrigeration mode, the control device 60 sets the cooling expansion valve 14c to a throttled state with respect to the single cooling mode.

[0259] Therefore, in the heat pump cycle 10a in the cooling and refrigeration mode, the refrigerant discharged from the compressor 11 circulates in the same manner as in the single cooling mode. At the same time, the refrigerant discharged from the compressor 11 is switched to a refrigerant circuit that circulates in the order of the water-cooled medium heat exchanger 13, the cooling expansion valve 14c in the throttled state, the chiller 20, the accumulator 23, and the suction port of the compressor 11. That is, the indoor evaporator 18 and the chiller 20 are switched to a refrigerant circuit connected in parallel with respect to the flow of the refrigerant.

[0260] Also, in the heat medium circuit 30a in the cooling and refrigeration mode, the control device 60 controls the operation of the high-temperature side pump 31 and the high-temperature side three-way valve 33 in the same manner as in the single cooling mode. Further, the control device 60 operates the low-temperature side pump 41 so as to exhibit a predetermined reference pumping capacity. In addition, the control device 60 controls the operation of the low-temperature side three-way valve 43 so that the total flow rate of the heat medium flowing out of the heat medium passage of the chiller 20 flows into the cooling water passage 70a of the battery 70.

[0261] Therefore, in the heat medium circuit 30a in the cooling and air - conditioning mode, the heat medium pumped from the high - temperature side pump 31 circulates in the same manner as in the single - air - conditioning mode. At the same time, the heat medium pumped from the low - temperature side pump 41 is switched to a circuit that circulates in the order of the chiller 20, the cooling water passage 70a of the battery 70, and the suction port of the low - temperature side pump 41.

[0262] Also, in the room air - conditioning unit 50 in the cooling and air - conditioning mode, similar to the single - air - conditioning mode, the control device 60 controls the rotation speed of the indoor blower 52, the opening degree of the air mix door 54, etc. Further, the control device 60 appropriately controls the operation of other controlled devices.

[0263] Therefore, in the heat pump cycle 10a in the cooling and air - conditioning mode, a vapor - compression refrigeration cycle is configured in which the water - cooled medium heat exchanger 13 functions as a condenser, and the indoor evaporator 18 and the chiller 20 function as evaporators. The suction - side refrigerant pressure PS in the cooling and air - conditioning mode is equivalent to that in the single - air - conditioning mode.

[0264] In the heat medium circuit 30a in the cooling and air - conditioning mode, similar to the single - air - conditioning mode, the heat medium heated by the water - cooled medium heat exchanger 13 flows into the heater core 32 and the radiator 34 according to the operation of the high - temperature side three - way valve 33.

[0265] Furthermore, the heat medium flowing into the heat medium passage of the chiller 20 exchanges heat with the low - pressure - side refrigerant decompressed by the cooling expansion valve 14c and is cooled. The heat medium cooled by the chiller 20 flows into the cooling water passage 70a of the battery 70 through the low - temperature side three - way valve 43. The heat medium flowing into the cooling water passage 70a of the battery 70 absorbs the device - side heat generated by the battery 70. As a result, the battery 70 is cooled.

[0266] The heat medium flowing out from the cooling water passage 70a of the battery 70 is sucked into the low - temperature side pump 41 and pumped into the heat medium passage of the chiller 20. Therefore, in the chiller 20 in the cooling and air - conditioning mode, the refrigerant absorbs the device - side heat generated by the battery 70 through the low - temperature side heat medium.

[0267] In the in-vehicle air conditioning unit 50 in the cooling and air-conditioning mode, similar to the single air-conditioning mode, the temperature-adjusted blown air is blown into the vehicle interior, thereby realizing the air-conditioning in the vehicle interior.

[0268] (b-1) Single dehumidifying and heating mode In the heat pump cycle 10a in the single dehumidifying and heating mode, the control device 60 sets the refrigerant expansion valve 14b for cooling in a throttled state, the refrigerant expansion valve 14c for cooling in a fully closed state, and the bypass side flow rate adjustment valve 14d in a fully closed state. Therefore, in the heat pump cycle 10a in the single dehumidifying and heating mode, the refrigerant circuit in which the refrigerant circulates is switched to the same as that in the single air-conditioning mode.

[0269] Also, in the heat medium circuit 30a in the single dehumidifying and heating mode, the control device 60 operates the high-temperature side pump 31 so as to exhibit a predetermined reference pressure feeding capacity. Further, the control device 60 controls the operation of the high-temperature side three-way valve 33 so that the total flow rate of the heat medium flowing out from the water-cooled heat exchanger 13 flows into the heater core 32.

[0270] Therefore, in the heat medium circuit 30a in the single dehumidifying and heating mode, the heat medium pumped from the high-temperature side pump 31 circulates in the order of the water-cooled heat exchanger 13, the heater core 32, and the suction port of the high-temperature side pump 31.

[0271] Also, in the in-vehicle air conditioning unit 50 in the single dehumidifying and heating mode, similar to the single air-conditioning mode, the control device 60 controls the rotation speed of the in-vehicle blower 52, the opening degree of the air mix door 54, etc. Further, the control device 60 appropriately controls the operation of other controlled devices.

[0272] Therefore, in the heat pump cycle 10a in the single dehumidifying and heating mode, a vapor compression refrigeration cycle is configured in which the water-cooled heat exchanger 13 functions as a condenser and the in-vehicle evaporator 18 functions as an evaporator. The suction side refrigerant pressure PS in the single dehumidifying and heating mode is equivalent to that in the single air-conditioning mode.

[0273] In the heat medium circuit 30a in the single dehumidifying and heating mode, the heat medium heated by the water-cooled heat exchanger 13 is pumped to the heater core 32.

[0274] In the in-vehicle air-conditioning unit 50 in the independent dehumidifying and heating mode, the blown air cooled and dehumidified by the in-vehicle evaporator 18 is reheated by the heater core 32. Then, the temperature-adjusted blown air is blown into the vehicle interior, thereby realizing dehumidifying and heating in the vehicle interior.

[0275] (b-2) Cooling dehumidifying and heating mode In the heat pump cycle 10a in the cooling dehumidifying and heating mode, the control device 60 sets the cooling expansion valve 14b in a throttled state, sets the cooling expansion valve 14c in a throttled state, and sets the bypass-side flow rate adjustment valve 14d in a fully closed state. Therefore, in the heat pump cycle 10a in the cooling dehumidifying and heating mode, the refrigerant circuit in which the refrigerant circulates is switched to the same as that in the cooling and cooling mode.

[0276] Also, in the heat medium circuit 30a in the cooling dehumidifying and heating mode, the control device 60 controls the operations of the high-temperature side pump 31 and the high-temperature side three-way valve 33 in the same manner as in the independent dehumidifying and heating mode. Further, the control device 60 operates the low-temperature side pump 41 so as to exhibit a predetermined reference pressure feeding capacity. In addition, the control device 60 controls the operation of the low-temperature side three-way valve 43 so that the total flow rate of the heat medium flowing out from the heat medium passage of the chiller 20 flows into the cooling water passage 70a of the battery 70.

[0277] Therefore, in the heat medium circuit 30a in the cooling dehumidifying and heating mode, the heat medium pumped from the high-temperature side pump 31 circulates in the same manner as in the independent dehumidifying and heating mode. Further, the heat medium pumped from the low-temperature side pump 41 circulates in the order of the chiller 20, the cooling water passage 70a of the battery 70, and the suction port of the low-temperature side pump 41.

[0278] Also, in the in-vehicle air-conditioning unit 50 in the cooling dehumidifying and heating mode, the control device 60 controls the rotation speed of the in-vehicle blower 52, the opening degree of the air mix door 54, etc. in the same manner as in the first embodiment. Further, the control device 60 appropriately controls the operations of other controlled devices.

[0279] Therefore, in the heat pump cycle 10a in the cooling dehumidification heating mode, a vapor compression refrigeration cycle is configured in which the water-cooled refrigerant heat exchanger 13 functions as a condenser and the indoor evaporator 18 and the chiller 20 function as evaporators. The suction-side refrigerant pressure PS in the cooling dehumidification heating mode is the same as that in the single cooling mode.

[0280] In the heat medium circuit 30a in the cooling dehumidification heating mode, the heat medium heated by the water-cooled refrigerant heat exchanger 13 is pumped to the heater core 32, similarly to the single dehumidification heating mode. Further, the heat medium cooled by the chiller 20 flows into the cooling water passage 70a of the battery 70. The heat medium that has flowed into the cooling water passage 70a of the battery 70 absorbs the equipment-side heat generated by the battery 70, similarly to the cooling cooling mode. As a result, the battery 70 is cooled.

[0281] In the indoor air conditioner unit 50 in the cooling dehumidification heating mode, dehumidification heating in the vehicle interior is realized by blowing out the temperature-adjusted blown air into the vehicle interior, similarly to the single dehumidification heating mode.

[0282] (c-1) Single outside air heat absorption heating mode In the heat pump cycle 10a in the single outside air heat absorption heating mode, the control device 60 fully closes the cooling expansion valve 14b, throttles the cooling expansion valve 14c, and fully closes the bypass-side flow rate adjustment valve 14d.

[0283] Therefore, in the heat pump cycle 10a in the single outside air heat absorption heating mode, as shown by the solid line arrow in FIG. 12, the refrigerant discharged from the compressor 11 is switched to a refrigerant circuit that circulates in the order of the water-cooled refrigerant heat exchanger 13, the cooling expansion valve 14c in the throttled state, the chiller 20, the accumulator 23, and the suction port of the compressor 11.

[0284] In the heat medium circuit 30a in the independent outdoor air heat absorption heating mode, the control device 60 controls the operations of the high-temperature side pump 31 and the high-temperature side three-way valve 33 in the same manner as in the independent dehumidifying heating mode. Further, the control device 60 operates the low-temperature side pump 41 so as to exhibit a predetermined reference pumping capacity. In addition, the control device 60 controls the operation of the low-temperature side three-way valve 43 so that the total flow rate of the heat medium flowing out from the heat medium passage of the chiller 20 flows into the radiator 34.

[0285] Therefore, in the heat medium circuit 30a in the independent outdoor air heat absorption heating mode, as shown by the dashed arrow in FIG. 12, the heat medium pumped from the high-temperature side pump 31 circulates in the same manner as in the independent dehumidifying heating mode. At the same time, the heat medium pumped from the low-temperature side pump 41 is switched to a circuit that circulates in the order of the chiller 20, the radiator 34, and the suction port of the low-temperature side pump 41.

[0286] In the indoor air conditioner unit 50 in the independent outdoor air heat absorption heating mode, the control device 60 controls the rotational speed of the indoor blower 52, the opening degree of the air mix door 54, etc. in the same manner as in the independent cooling mode. Further, the control device 60 appropriately controls the operations of other controlled devices.

[0287] Therefore, in the heat pump cycle 10a in the independent outdoor air heat absorption heating mode, a vapor compression refrigeration cycle is configured in which the water-cooled medium heat exchanger 13 functions as a condenser and the chiller 20 functions as an evaporator. The suction side refrigerant pressure PS in the independent outdoor air heat absorption heating mode is equivalent to that in the independent outdoor air heat absorption heating mode of the first embodiment. For this reason, the refrigerant pressure in the accumulator 23 during the independent outdoor air heat absorption heating mode is likely to be lower than the refrigerant pressure in the accumulator 23 during the independent cooling mode or the like.

[0288] In the heat medium circuit 30a of the independent outdoor air heat absorption heating mode, similar to the independent dehumidification heating mode, the heat medium heated by the water-cooled heat exchanger 13 is pumped to the heater core 32. Further, the heat medium cooled by the chiller 20 flows into the radiator 34. The heat medium flowing into the radiator 34 absorbs the outdoor air side heat of the outdoor air. The heat medium that has absorbed the outdoor air side heat in the radiator 34 is sucked by the low-temperature side pump 41 and pumped to the heat medium passage of the chiller 20.

[0289] In the indoor air conditioner unit 50 of the independent outdoor air heat absorption heating mode, the blown air blown from the indoor blower 52 passes through the indoor evaporator 18. The blown air that has passed through the indoor evaporator 18 is heated by exchanging heat with the high-temperature side heat medium in the heater core 32 according to the opening degree of the air mix door 54. Then, the blown air whose temperature is adjusted to approach the target blow-out temperature TAO is blown into the vehicle interior. Thereby, heating in the vehicle interior is realized.

[0290] (c-2) Cooling outdoor air heat absorption heating mode In the heat pump cycle 10a of the cooling outdoor air heat absorption heating mode, the control device 60 fully closes the cooling expansion valve 14b, sets the cooling expansion valve 14c in a throttled state, and fully closes the bypass side flow rate adjustment valve 14d. Therefore, in the heat pump cycle 10a of the cooling outdoor air heat absorption heating mode, it is switched to the same refrigerant circuit as the independent outdoor air heat absorption heating mode.

[0291] Also, in the heat medium circuit 30a of the cooling outdoor air heat absorption heating mode, the control device 60 controls the operations of the high-temperature side pump 31 and the high-temperature side three-way valve 33 in the same manner as in the independent dehumidification heating mode.

[0292] Furthermore, the control device 60 operates the low-temperature side pump 41 so as to exhibit a predetermined reference pumping capacity. Also, the control device 60 controls the operation of the low-temperature side three-way valve 43 so that the low-temperature side heat medium temperature TWL detected by the low-temperature side heat medium temperature sensor 63b approaches a predetermined reference low-temperature side heat medium temperature KTWL.

[0293] Therefore, in the heat medium circuit 30a in the cooling outside air heat absorption heating mode, the heat medium pumped from the high-temperature side pump 31 circulates in the same manner as in the independent outside air heat absorption heating mode. Further, the heat medium pumped from the low-temperature side pump 41 circulates in the order of the chiller 20, the cooling water passage 70a of the battery 70, and the suction port of the low-temperature side pump 41. At the same time, the heat medium pumped from the low-temperature side pump 41 is switched to a circuit that circulates in the order of the chiller 20, the radiator 34, and the suction port of the low-temperature side pump 41.

[0294] Also, in the indoor air conditioner unit 50 in the cooling outside air heat absorption heating mode, the control device 60 controls the rotation speed of the indoor blower 52, the opening degree of the air mix door 54, etc. in the same manner as in the independent cooling mode. Further, the control device 60 appropriately controls the operation of other controlled devices.

[0295] Therefore, in the heat pump cycle 10a in the cooling and heating mode, a vapor compression refrigeration cycle is configured in which the water-cooled medium heat exchanger 13 functions as a condenser and the chiller 20 functions as an evaporator, in the same manner as in the independent outside air heat absorption heating mode. The suction side refrigerant pressure PS in the cooling outside air heat absorption heating mode is equivalent to that in the independent outside air heat absorption heating mode.

[0296] In the heat medium circuit 30a in the cooling outside air heat absorption heating mode, the heat medium heated by the water-cooled medium heat exchanger 13 is pumped to the heater core 32, in the same manner as in the cooling and dehumidifying heating mode. The heat medium cooled by the chiller 20 flows into the cooling water passage 70a of the battery 70 and the radiator 34 according to the operation of the low-temperature side three-way valve 43.

[0297] The heat medium that has flowed into the cooling water passage 70a of the battery 70 absorbs the heat generated by the equipment side of the battery 70. The heat medium that has flowed into the radiator 34 absorbs the outside air side heat of the outside air. Therefore, in the chiller 20 in the cooling outside air heat absorption heating mode, the refrigerant absorbs the equipment side heat and the outside air side heat through the low-temperature side heat medium according to the operation of the low-temperature side three-way valve 43.

[0298] In the in-vehicle air conditioning unit 50 in the cooling outside air heat absorption heating mode, similar to the single outside air heat absorption heating mode, heated air whose temperature has been adjusted is blown into the vehicle interior, thereby realizing heating in the vehicle interior.

[0299] (c-3) Waste heat recovery heating mode In the heat pump cycle 10a in the waste heat recovery heating mode, the control device 60 fully closes the cooling expansion valve 14b, sets the cooling expansion valve 14c in a throttled state, and fully closes the bypass side flow rate adjustment valve 14d. Therefore, in the heat pump cycle 10a in the cooling outside air heat absorption heating mode, as shown by the solid line arrows in FIG. 13, it is switched to the same refrigerant circuit as the single outside air heat absorption heating mode.

[0300] Also, in the heat medium circuit 30a in the waste heat recovery heating mode, the control device 60 controls the operation of the high-temperature side pump 31 and the high-temperature side three-way valve 33 in the same manner as in the single dehumidifying heating mode. Further, the control device 60 controls the operation of the low-temperature side pump 41 and the low-temperature side three-way valve 43 in the same manner as in the cooling and refrigeration mode.

[0301] Therefore, in the heat medium circuit 30a in the waste heat recovery heating mode, as shown by the dashed line arrows in FIG. 13, the heat medium pumped from the high-temperature side pump 31 circulates in the same manner as in the single dehumidifying heating mode. Also, the heat medium pumped from the low-temperature side pump 41 circulates in the same manner as in the cooling and refrigeration mode.

[0302] Also, in the in-vehicle air conditioning unit 50 in the waste heat recovery heating mode, the control device 60 controls the rotation speed of the in-vehicle blower 52, the opening degree of the air mix door 54, etc. in the same manner as in the single refrigeration mode. Further, the control device 60 appropriately controls the operation of other controlled devices.

[0303] Therefore, in the heat pump cycle 10a in the cooling and heating mode, a vapor compression refrigeration cycle is configured in which the water-cooled medium heat exchanger 13 functions as a condenser and the chiller 20 functions as an evaporator, similar to the single outside air heat absorption heating mode.

[0304] The suction-side refrigerant pressure PS in the waste heat recovery heating mode is the same as that in the waste heat recovery heating mode of the first embodiment. Therefore, the refrigerant pressure in the accumulator 23 in the waste heat recovery heating mode is likely to be higher than the refrigerant pressure in the accumulator 23 in the single outside air heat absorption heating mode or the like.

[0305] Also, in the heat medium circuit 30a in the waste heat recovery heating mode, similar to the single dehumidification heating mode, the heat medium heated by the water-cooled heat exchanger 13 is pumped to the heater core 32. Also, similar to the cooling and cooling mode, the heat medium cooled by the chiller 20 is pumped to the cooling water passage 70a of the battery 70.

[0306] In the room air conditioner unit 50 in the waste heat recovery heating mode, similar to the single outside air heat absorption heating mode, the temperature-adjusted blown air is blown into the vehicle interior, thereby realizing heating in the vehicle interior.

[0307] (d) Hot gas heating mode In the hot gas heating mode, the control device 60 fully closes the cooling expansion valve 14b, throttles the cooling expansion valve 14c, and throttles the bypass-side flow rate adjustment valve 14d.

[0308] Therefore, in the heat pump cycle 10a in the hot gas heating mode, as shown by the solid line arrows in FIG. 14, the refrigerant discharged from the compressor 11 circulates in the order of the water-cooled heat exchanger 13, the cooling expansion valve 14c in the throttled state, the chiller 20, and the suction port of the compressor 11. At the same time, the refrigerant discharged from the compressor 11 is switched to a refrigerant circuit in which the refrigerant circulates in the order of the bypass-side flow rate adjustment valve 14d in the throttled state, the chiller 20, and the suction port of the compressor 11.

[0309] Also, in the heat medium circuit 30a in the hot gas heating mode, the control device 60 controls the operations of the high-temperature side pump 31 and the high-temperature side three-way valve 33 in the same manner as in the single dehumidifying heating mode. Further, the control device 60 stops the low-temperature side pump 41. Therefore, in the heat medium circuit 30a in the hot gas heating mode, as shown by the broken-line arrow in FIG. 14, the heat medium pumped from the high-temperature side pump 31 circulates in the same manner as in the single dehumidifying heating mode.

[0310] Also, in the indoor air conditioner unit 50 in the hot gas heating mode, the control device 60 controls the rotational speed of the indoor blower 52, the opening degree of the air mix door 54, etc. in the same manner as in the single cooling mode. Further, the control device 60 appropriately controls the operations of other controlled devices.

[0311] Therefore, in the heat pump cycle 10a in the hot gas heating mode, it operates in the same manner as the hot gas heating mode of the first embodiment. For this reason, in the hot gas heating mode, the suction side refrigerant pressure PS is adjusted to be higher than in all heating modes.

[0312] In the heat medium circuit 30a in the hot gas heating mode, the high-temperature side heat medium heated by the water-cooled heat exchanger 13 is pumped to the heater core 32 in the same manner as in the single dehumidifying heating mode.

[0313] In the indoor air conditioner unit 50 in the hot gas heating mode, in the same manner as in the single outdoor air heat absorption heating mode, the temperature-adjusted blown air is blown into the vehicle interior, thereby realizing heating of the vehicle interior.

[0314] As described above, in the vehicle air conditioner 1a of the present embodiment, by switching the operation mode, it is possible to perform comfortable air conditioning in the vehicle interior and appropriate temperature adjustment of the battery 70 which is an in-vehicle device.

[0315] Furthermore, also in the control program of the present embodiment, in the same manner as in the first embodiment, when switching from the first operation mode to the second operation mode, liquid amount reduction control is performed.

[0316] In this embodiment, when the hot gas heating mode is defined as the first operation mode, the independent outdoor air heat absorption heating mode, the cooling outdoor air heat absorption heating mode, and the waste heat recovery heating mode can be defined as the second operation mode. When the hot gas heating mode is defined as the first operation mode, the recovery flow path 24a is formed by a refrigerant flow path that extends from one outlet of the seventh three-way joint 12g, passes through the cooling expansion valve 14b and the indoor evaporator 18, and reaches the fifth three-way joint 12e.

[0317] Also, when the waste heat recovery heating mode is defined as the first operation mode, the independent outdoor air heat absorption heating mode and the cooling outdoor air heat absorption heating mode can be defined as the second operation mode. When the waste heat recovery heating mode is defined as the first operation mode, the recovery flow path 24a is formed by a refrigerant flow path that extends from one outlet of the seventh three-way joint 12g, passes through the cooling expansion valve 14b and the indoor evaporator 18, and reaches the fifth three-way joint 12e.

[0318] In the liquid amount reduction control of this embodiment, as shown in the time charts of FIGS. 15 and 16, the operation of each component device is controlled. The time chart of FIG. 15 shows an example in which the hot gas heating mode is defined as the first operation mode and the independent outdoor air heat absorption heating mode is defined as the second operation mode.

[0319] In the liquid amount reduction control of FIG. 15, the cooling expansion valve 14b is changed from the fully closed state to the throttled state. That is, in the liquid amount reduction control, the cooling expansion valve 14b is opened. At this time, the opening degree of the cooling expansion valve 14b is set to a minute opening degree that does not affect the high and low pressure balance of the heat pump cycle 10a in the hot gas heating mode.

[0320] As a result, in the liquid amount reduction control, refrigerant flows into the recovery flow path 24a. That is, a part of the high-pressure side refrigerant flowing out from the water-cooled refrigerant heat exchanger 13 flows into the indoor evaporator 18 via the cooling expansion valve 14b. The refrigerant flowing into the indoor evaporator 18 condenses and is stored as liquid in the indoor evaporator 18. As a result, the amount of liquid-phase refrigerant in the accumulator 23 is reduced.

[0321] Thereafter, wait for the elapse of a predetermined recovery time Tmc and then end the liquid volume reduction control. Then, after the end of the liquid volume reduction control, switch to the independent outside air heat absorption heating mode.

[0322] Also, when the hot gas heating mode is defined as the first operation mode and the cooling outside air heat absorption heating mode is defined as the second operation mode, the same liquid volume reduction control as in FIG. 15 may be performed. In this case, when the independent outside air heat absorption heating mode is defined as the second operation mode, after the end of the liquid volume reduction control, the operation of the low-temperature side three-way valve 43 may be controlled so that the low-temperature side heat medium temperature TWL approaches the reference low-temperature side heat medium temperature KTWL.

[0323] Also, when the hot gas heating mode is defined as the first operation mode and the waste heat recovery heating mode is defined as the second operation mode, the same liquid volume reduction control as in FIG. 15 may be performed. In this case, when the independent outside air heat absorption heating mode is defined as the second operation mode, after the end of the liquid volume reduction control, the operation of the low-temperature side three-way valve 43 may be controlled so that the total flow rate of the heat medium flowing out from the heat medium passage of the chiller 20 flows into the cooling water passage 70a of the battery 70.

[0324] Here, in FIG. 15, an example is illustrated in which the operation of the low-temperature side three-way valve 43 is controlled so that the total flow rate of the heat medium flowing out from the heat medium passage of the chiller 20 flows into the cooling water passage 70a of the battery 70 during the hot gas heating mode and the execution of the liquid volume reduction control, but it is not limited thereto. In the hot gas heating mode, since the low-temperature side pump 41 is stopped, the opening degree of the low-temperature side three-way valve 43 may be any opening degree.

[0325] Also, the time chart of FIG. 16 shows an example in which the waste heat recovery heating mode is defined as the first operation mode and the independent outside air heat absorption heating mode is defined as the second operation mode. Also in the liquid volume reduction control of FIG. 16, the refrigerant expansion valve 14b for cooling is changed from the fully closed state to the throttle state. Thereby, the liquid phase refrigerant amount in the accumulator 23 can be reduced in the same manner as the liquid volume reduction control of FIG. 15.

[0326] Also, when the waste heat recovery heating mode is defined as the first operation mode and the cooling outside air heat absorption heating mode is defined as the second operation mode, the same liquid volume reduction control as in FIG. 16 may be performed. In this case, compared with the case where the single outside air heat absorption heating mode is defined as the second operation mode, after the liquid volume reduction control ends, the operation of the low-temperature side three-way valve 43 may be controlled so that the low-temperature side heat medium temperature TWL approaches the reference low-temperature side heat medium temperature KTWL.

[0327] As described above, according to the vehicle air conditioner 1a of the present embodiment, when switching from the first operation mode to the second operation mode, since the liquid volume reduction control is performed, the same effect as in the first embodiment can be obtained. That is, even in a heat pump cycle device equipped with an accumulator 23 and configured to be able to switch the operation mode like the vehicle air conditioner 1a of the present embodiment, the compressor 11 can be appropriately protected.

[0328] (Fifth Embodiment) In the present embodiment, as shown in the overall configuration diagram of FIG. 18, an example in which the first three-way joint 12a, the sixth three-way joint 12f, the bypass passage 21a, and the bypass side flow rate adjustment valve 14d of the heat pump cycle 10a are abolished with respect to the fourth embodiment will be described. The configuration of the other vehicle air conditioner 1 is the same as that of the first embodiment.

[0329] In the vehicle air conditioner 1 of the present embodiment, the operations in (a) the cooling mode, (b) the dehumidifying heating mode, and (c) the heating mode described in the first embodiment can be executed.

[0330] Therefore, in the vehicle air conditioner 1 of the present embodiment, the waste heat recovery heating mode is defined as the first operation mode, and the single outside air heat absorption heating mode or the cooling outside air heat absorption heating mode is defined as the second operation mode. Then, when switching from the first operation mode to the second operation mode, by performing the liquid volume reduction control, the same effect as in the first embodiment can be obtained.

[0331] That is, in the vehicle air conditioner 1a of the present embodiment, even in a heat pump cycle device including an accumulator 23 and configured to be able to switch the operation mode, the compressor 11 can be appropriately protected.

[0332] (Other embodiments) The present invention is not limited to the above-described embodiments, and various modifications can be made as follows without departing from the gist of the present invention.

[0333] (1) In the above-described embodiment, an example in which the heat pump cycle device according to the present invention is applied to a vehicle air conditioner has been described. However, the application target of the heat pump cycle device is not limited to a vehicle air conditioner. For example, it may be applied to an air conditioner that only performs air conditioning of the air-conditioned space without adjusting the temperature of the heat generating device. For example, it may be applied to a water heater that heats domestic water or the like as a heating target.

[0334] Further, in the above-described embodiment, an example in which the temperature of the battery 70 is adjusted as an in-vehicle device to be temperature-adjusted has been described. However, the in-vehicle device is not limited to the battery 70. For example, it may be configured to adjust the temperature of an inverter, a PCU, a transaxle, a control device for ADAS, or the like. Furthermore, it may be configured to adjust the temperatures of a plurality of in-vehicle devices.

[0335] The inverter supplies power to a motor generator or the like. The PCU is a power control unit that performs power conversion and power distribution. The transaxle is a power transmission mechanism that integrates a transmission, a differential gear, and the like. The control device for ADAS is a control device for an advanced driver assistance system.

[0336] (2) The configuration of the heat pump cycle device according to the present invention is not limited to the configuration disclosed in the above-described embodiment.

[0337] In the above-described embodiments, an example in which the heating unit is formed by each component device of the water-cooled medium heat exchanger 13 and the high-temperature side heat medium circuit 30, or each component device of the water-cooled medium heat exchanger 13 and the heat medium circuit 30a has been described, but the present invention is not limited thereto.

[0338] For example, an indoor condenser may be employed as the heating unit. The indoor condenser is a heat exchange unit for heating the blown air by exchanging heat between one of the discharged refrigerants branched by the first three-way joint 12a and the blown air that has passed through the indoor evaporator 18. Then, the indoor condenser may be arranged in the air passage of the indoor air conditioning unit 50 in the same manner as the heater core 32.

[0339] Further, in the above-described embodiments, an example in which the sixth three-way joint 12f, which is the mixing unit, is arranged on the upstream side of the refrigerant flow of the chiller 20 has been described, but the present invention is not limited thereto.

[0340] For example, it may be arranged on the downstream side of the refrigerant flow of the chiller 20. In this case, the refrigerant flowing out from the bypass side flow rate adjustment valve 14d and the refrigerant flowing out from the refrigerant passage of the chiller 20 are uniformly mixed when flowing through the refrigerant pipe leading from the accumulator 23 or the sixth three-way joint 12f to the suction side of the compressor 11. For example, the sixth three-way joint 12f may be omitted and the end of the bypass passage 21a may be directly connected to the accumulator 23.

[0341] Further, in the above-described fourth embodiment, an example in which the heat medium circuit 30a is employed has been described, but the present invention is not limited thereto. For example, similar to the first embodiment, independent high-temperature side heat medium circuit 30 and low-temperature side heat medium circuit 40 may be employed.

[0342] In this case, a high-temperature side three-way valve 33 and a high-temperature side radiator may be arranged in the high-temperature side heat medium circuit 30. The high-temperature side radiator is a high-temperature side heat medium heat dissipation unit that exchanges heat between the high-temperature side heat medium and the outside air discharge. Then, the high-temperature side three-way valve 33 may be arranged so that the flow rate ratio between the flow rate of the high-temperature side heat medium flowing into the heater core 32 and the flow rate of the high-temperature side heat medium flowing into the high-temperature side radiator can be adjusted.

[0343] Furthermore, a low-temperature-side three-way valve 43 and a low-temperature-side radiator may be arranged in the low-temperature-side heat medium circuit 40. The low-temperature-side radiator is a high-temperature-side heat medium heat radiation part that exchanges heat between the low-temperature-side heat medium and the outside air discharge. Then, the low-temperature-side three-way valve 43 may be arranged so that the flow rate ratio between the flow rate of the low-temperature-side heat medium flowing into the cooling water passage 70a of the battery 70 and the flow rate of the low-temperature-side heat medium flowing into the low-temperature-side radiator can be adjusted.

[0344] In addition, in the above-described embodiment, an example in which the second check valve 16b is adopted has been described. However, an evaporation pressure regulating valve may be adopted instead of the second check valve 16b. The evaporation pressure regulating valve is a variable throttle mechanism that maintains the refrigerant evaporation temperature in the indoor evaporator 18 at a predetermined temperature (for example, a temperature at which the indoor evaporator 18 can be suppressed) or higher.

[0345] As the evaporation pressure regulating valve, a variable throttle mechanism configured by a mechanical mechanism that increases the valve opening degree as the pressure of the refrigerant on the refrigerant outlet side of the indoor evaporator 18 increases may be adopted. Also, as the evaporation pressure regulating valve, a variable throttle mechanism configured by an electric mechanism similar to the heating expansion valve 14a or the like may be adopted.

[0346] In addition, in the above-described embodiment, an example in which R1234yf is adopted as the refrigerant of the heat pump cycles 10 and 10a has been described, but it is not limited thereto. For example, R134a, R600a, R410A, R404A, R32, R407C, etc. may be adopted. Or, a mixed refrigerant in which a plurality of these refrigerants are mixed may be adopted. Furthermore, carbon dioxide may be adopted as the refrigerant to constitute a transcritical refrigeration cycle in which the high-pressure-side refrigerant pressure becomes equal to or higher than the critical pressure of the refrigerant.

[0347] In addition, in the above-described embodiment, an example in which PAG oil (that is, polyalkylene glycol oil) is adopted as the refrigeration oil has been described, but it is not limited thereto. For example, POE (that is, polyol ester) or the like may be adopted.

[0348] In addition, in the above-described embodiments, an example in which an ethylene glycol aqueous solution is employed as the heat medium, the low-temperature-side heat medium, and the high-temperature-side heat medium has been described, but the present invention is not limited thereto. For example, dimethylpolysiloxane, or a solution containing a nanofluid or the like, an antifreeze, an aqueous liquid refrigerant containing alcohol or the like, a liquid medium containing oil or the like may be employed.

[0349] Further, the control sensor group connected to the input side of the control device 60 is not limited to the detection unit disclosed in the above-described embodiments. Various detection units may be added as necessary.

[0350] (3) The control mode of the heat pump cycle device according to the present invention is not limited to the control mode disclosed in the above-described embodiments.

[0351] In the above-described embodiments, the vehicle air conditioners 1 and 1a capable of executing various operation modes have been described, but the heat pump cycle device according to the present invention does not necessarily need to be capable of executing all the above-described operation modes. As long as it is possible to execute a combination of operation modes corresponding to at least one or more first operation modes and second operation modes, the same effects as those of the above-described embodiments can be obtained.

[0352] Furthermore, the vehicle air conditioners 1 and 1a may be capable of executing other operation modes. For example, it may be possible to execute an equipment cooling mode in which only the battery 70 is cooled without performing air conditioning in the vehicle interior. Specifically, when executing the equipment cooling mode, the control device 60 switches the refrigerant circuit of the heat pump cycles 10 and 10a in the same manner as in the cooling mode, and fully closes the cooling expansion valve 14b. Further, the control device 60 may stop the indoor blower 52.

[0353] For example, in the vehicle air conditioner 1 of the first embodiment, with respect to the flow of the discharged refrigerant discharged from the compressor 11, the water-cooled refrigerant heat exchanger 13, the outdoor heat exchanger 15, and the indoor evaporator 18 may be connected in series to execute a series dehumidifying and heating mode for performing dehumidifying and heating in the vehicle interior. Further, with respect to the flow of the refrigerant flowing out from the water-cooled refrigerant heat exchanger 13, the outdoor heat exchanger 15 and the indoor evaporator 18 may be connected in parallel to execute a parallel dehumidifying and heating mode for performing dehumidifying and heating in the vehicle interior.

[0354] Similarly, in the vehicle air conditioner 1a of the fourth embodiment, for the single dehumidifying and heating mode, the cooling expansion valve 14c is set in a throttled state. Then, the low-temperature side pump 41 is operated, and an outdoor air heat absorption dehumidifying and heating mode may be executed by controlling the operation of the low-temperature side three-way valve 43 so that the entire flow rate of the heat medium flowing out from the heat medium passage of the chiller 20 flows into the radiator 34.

[0355] The features of the heat pump cycle device disclosed in this specification are shown as follows. (Item 1) An accumulator (23) that separates the gas and liquid of the refrigerant and stores the separated liquid-phase refrigerant, A compressor (11) that sucks and compresses the gas-phase refrigerant separated by the accumulator, An operation mode switching unit (14a to 14d, 22a, 22b, 43) that switches the operation mode, and As operation modes that can be switched by the operation mode switching unit, a first operation mode and a second operation mode in which the suction-side refrigerant pressure (PS), which is the refrigerant pressure in the accumulator, is lower than that in the first operation mode, In a refrigerant flow path through which the refrigerant does not flow when the operation mode switching unit switches to the first operation mode, a recovery flow path (24, 24a) for allowing the refrigerant to flow in is formed, A heat pump cycle device that performs liquid amount reduction control for reducing the amount of liquid-phase refrigerant in the accumulator by allowing the refrigerant to flow into the recovery flow path when the operation mode switching unit switches the operation mode from the first operation mode to the second operation mode. (Item 2) The heat pump cycle device according to item 1, wherein the recovery flow path is formed so as to be able to connect a portion where the refrigerant on the high-pressure side flows and a portion where the refrigerant on the low-pressure side flows during the first operation mode. (Item 3) The heat pump cycle device according to item 1 or 2, wherein the recovery flow path is formed in a portion where the refrigerant flows during the second operation mode. (Item 4) A discharge-side branch portion (12a) that branches the flow of the refrigerant discharged from the compressor, A heating portion (13, 30) that heats an object to be heated using the refrigerant flowing out from one outlet of the discharge-side branch portion as a heat source, A bypass passage (21a) through which the refrigerant flowing out from the other outlet of the discharge-side branch portion flows, An outdoor heat absorption portion (15) that causes the refrigerant to absorb the outdoor-side heat of the outside air, and is provided with, The operation mode switching portion has an outdoor pressure reducing portion (14a) that reduces the pressure of the refrigerant flowing into the outdoor heat absorption portion, and a bypass-side flow rate adjusting portion (14d) that adjusts the flow rate of the refrigerant flowing through the bypass passage. The operation mode switching portion, During the first operation mode, the refrigerant discharged from the compressor circulates in the order of the discharge-side branch portion, the heating portion, the accumulator, and the suction port of the compressor, and is switched to a refrigerant circuit that circulates in the order of the discharge-side branch portion, the bypass passage, the accumulator, and the suction port of the compressor. During the second operation mode, the refrigerant discharged from the compressor is switched to a refrigerant circuit that circulates in the order of the heating portion, the outdoor pressure reducing portion, the outdoor heat absorption portion, the accumulator, and the suction port of the compressor. The heat pump cycle device according to any one of items 1 to 3. (Item 5) A heating portion (13, 30) that heats an object to be heated using the refrigerant discharged from the compressor as a heat source, An outdoor heat absorption portion (15) that causes the refrigerant to absorb the outdoor-side heat of the outside air, An equipment heat absorption part (20) that allows the refrigerant to absorb the equipment-side heat generated by a heat-generating device (70) that generates heat during operation. The operation mode switching part has an outdoor air pressure reduction part (14a) that reduces the pressure of the refrigerant flowing into the outdoor air heat absorption part, and an equipment pressure reduction part (14c) that reduces the pressure of the refrigerant flowing into the equipment heat absorption part. The operation mode switching part During the first operation mode, the refrigerant discharged from the compressor is switched to a refrigerant circuit that circulates through the heating part, the equipment pressure reduction part, the equipment heat absorption part, the accumulator, and the suction port of the compressor. During the second operation mode, the refrigerant discharged from the compressor is switched to a refrigerant circuit that circulates through the heating part, the outdoor air pressure reduction part, the outdoor air heat absorption part, the accumulator, and the suction port of the compressor. The heat pump cycle device according to any one of Items 1 to 3. (Item 6) The outdoor air pressure reduction part and the outdoor air heat absorption part form the recovery flow path. In the liquid volume reduction control, the heat pump cycle device according to Item 4 or 5 that opens the outdoor air pressure reduction part. (Item 7) A discharge side branch part (12a) that branches the flow of the refrigerant discharged from the compressor. A heating part (13, 30) that heats a heating object using the refrigerant flowing out from one outlet of the discharge side branch part as a heat source. A bypass passage (21a) through which the refrigerant flowing out from the other outlet of the discharge side branch part flows. An equipment heat absorption part (20) that allows the refrigerant to absorb the equipment-side heat generated by a heat-generating device (70) that generates heat during operation. The operation mode switching part has an equipment pressure reduction part (14c) that reduces the pressure of the refrigerant flowing into the equipment heat absorption part (20), and a bypass side flow rate adjustment part (14d) that adjusts the flow rate of the refrigerant flowing through the bypass passage. The operation mode switching part In the first operation mode, the refrigerant discharged from the compressor circulates in the order of the discharge-side branch portion, the heating portion, the accumulator, and the suction port of the compressor, and is switched to a refrigerant circuit that circulates in the order of the discharge-side branch portion, the bypass passage, the accumulator, and the suction port of the compressor. In the second operation mode, the refrigerant discharged from the compressor is switched to a refrigerant circuit that circulates in the order of the heating portion, the equipment decompression portion, the equipment heat absorption portion, the accumulator, and the suction port of the compressor. The heat pump cycle device according to item 1 or 2. (Item 8) A discharge-side branch portion (12a) that branches the flow of the refrigerant discharged from the compressor, A heating portion (13, 30a) that heats an object to be heated using the refrigerant flowing out from one outlet of the discharge-side branch portion as a heat source, A bypass passage (21a) through which the refrigerant flowing out from the other outlet of the discharge-side branch portion flows, A shared heat absorption portion (20) that absorbs at least one of the heat on the equipment side generated by the heat-generating equipment (70) that generates heat during operation and the heat on the outside air side of the outside air into the refrigerant. The operation mode switching unit includes a shared decompression unit (14c) that decompresses the refrigerant flowing into the shared heat absorption portion, a bypass-side flow rate adjustment unit (14d) that adjusts the flow rate of the refrigerant flowing through the bypass passage, and a heat absorption ratio adjustment unit (43) that adjusts the ratio of the heat on the outside air side to the heat on the equipment side in the heat absorbed by the refrigerant in the shared heat absorption portion. The operation mode switching unit In the first operation mode, the refrigerant discharged from the compressor circulates in the order of the discharge-side branch portion, the heating portion, the accumulator, and the suction port of the compressor, and is switched to a refrigerant circuit that circulates in the order of the discharge-side branch portion, the bypass passage, the accumulator, and the suction port of the compressor. Further, the heat absorption of the refrigerant in the shared heat absorption portion is stopped. In the second operation mode, the refrigerant discharged from the compressor is switched to a refrigerant circuit that circulates in the order of the heating unit, the decompression unit, the common heat absorption unit, the accumulator, and the suction port of the compressor, and further, at least one of the heat of the outside air and the heat generated by the heat generating device is absorbed by the refrigerant in the common heat absorption unit. The heat pump cycle device according to item 1 or 2. (Item 9) A heating unit (13, 30a) that heats an object to be heated using the refrigerant discharged from the compressor as a heat source, A common heat absorption unit (20) that absorbs at least one of the outside air heat of the outside air and the equipment side heat generated by the heat generating device (70) that generates heat during operation into the refrigerant, The operation mode switching unit has a common decompression unit (14c) that decompresses the refrigerant flowing into the common heat absorption unit, and a heat absorption ratio adjustment unit (43) that adjusts the ratio of the outside air heat and the equipment side heat in the heat absorbed by the refrigerant in the common heat absorption unit. The operation mode switching unit In the first operation mode, the refrigerant discharged from the compressor is switched to a refrigerant circuit that circulates in the order of the heating unit, the heat absorption side decompression unit, the common heat absorption unit, the accumulator, and the suction port of the compressor, and further, the equipment side heat is absorbed by the refrigerant in the common heat absorption unit. In the second operation mode, the refrigerant discharged from the compressor is switched to a refrigerant circuit that circulates in the order of the heating unit, the heat absorption side decompression unit, the common heat absorption unit, the accumulator, and the suction port of the compressor, and further, the outside air heat is absorbed by the refrigerant in the common heat absorption unit. The heat pump cycle device according to item 1 or 2.

Description of symbols

[0356] 1, 1a Vehicle air conditioner (heat pump cycle device) 11 Compressor 14a, 14b Expansion valve for heating, expansion valve for cooling (operation mode switching unit) 14c Expansion valve for cooling (equipment decompression unit, common decompression unit: operation mode switching unit) 14d bypass side flow rate adjustment valve (bypass side flow rate adjustment unit: operation mode switching unit) 22a, 22b dehumidification on-off valve, heating on-off valve (operation mode switching unit) 23 accumulator 24, 24a recovery flow path 43 low-temperature side three-way valve (heat absorption ratio adjustment unit)

Claims

1. An accumulator (23) that separates the gas and liquid of the refrigerant and stores the separated liquid-phase refrigerant, A compressor (11) that sucks and compresses the gas-phase refrigerant separated by the accumulator, An operation mode switching unit (14a to 14d, 22a, 22b, 43) that switches the operation mode, and As operation modes that can be switched by the operation mode switching unit, there are a first operation mode and a second operation mode in which the suction-side refrigerant pressure (PS), which is the refrigerant pressure in the accumulator, is lower than that in the first operation mode, In a refrigerant flow path where the refrigerant does not flow when the operation mode switching unit switches to the first operation mode, a recovery flow path (24, 24a) through which the refrigerant can flow in is formed, A heat pump cycle device that performs liquid amount reduction control to reduce the amount of liquid-phase refrigerant in the accumulator by causing the refrigerant to flow into the recovery flow path when the operation mode switching unit switches the operation mode from the first operation mode to the second operation mode.

2. The heat pump cycle device according to claim 1, wherein the recovery flow path is formed so as to be able to connect a part where the refrigerant on the high-pressure side flows and a part where the refrigerant on the low-pressure side flows during the first operation mode.

3. The heat pump cycle device according to claim 1 or 2, wherein the recovery flow path is formed at a part where the refrigerant flows during the second operation mode.

4. A discharge-side branch portion (12a) that branches the flow of the refrigerant discharged from the compressor, A heating unit (13, 30) that heats an object to be heated using the refrigerant flowing out from one outlet of the discharge-side branch portion as a heat source, A bypass passage (21a) through which the refrigerant flowing out from the other outlet of the discharge-side branch portion flows, An outdoor heat absorption unit (15) that causes the refrigerant to absorb the outdoor-side heat of the outside air, and The operation mode switching unit has an outdoor pressure reducing unit (14a) that reduces the pressure of the refrigerant flowing into the outdoor heat absorbing unit, and a bypass side flow rate adjusting unit (14d) that adjusts the flow rate of the refrigerant flowing through the bypass passage. The operation mode switching unit In the first operation mode, the refrigerant discharged from the compressor circulates in the order of the discharge side branch portion, the heating unit, the accumulator, and the suction port of the compressor, and is switched to a refrigerant circuit that circulates in the order of the discharge side branch portion, the bypass passage, the accumulator, and the suction port of the compressor. The heat pump cycle device according to claim 1, wherein in the second operation mode, the refrigerant discharged from the compressor is switched to a refrigerant circuit that circulates in the order of the heating unit, the outdoor pressure reducing unit, the outdoor heat absorbing unit, the accumulator, and the suction port of the compressor.

5. A heating unit (13, 30) that heats an object to be heated using the refrigerant discharged from the compressor as a heat source, An outdoor heat absorbing unit (15) that absorbs the outdoor side heat of the outside air by the refrigerant, A device heat absorbing unit (20) that absorbs the device side heat generated by a heat generating device (70) that generates heat during operation by the refrigerant, and is provided with The operation mode switching unit has an outdoor pressure reducing unit (14a) that reduces the pressure of the refrigerant flowing into the outdoor heat absorbing unit, and a device pressure reducing unit (14c) that reduces the pressure of the refrigerant flowing into the device heat absorbing unit. The operation mode switching unit In the first operation mode, the refrigerant discharged from the compressor is switched to a refrigerant circuit that circulates through the heating unit, the device pressure reducing unit, the device heat absorbing unit, the accumulator, and the suction port of the compressor. The heat pump cycle device according to claim 1, wherein in the second operation mode, the refrigerant discharged from the compressor is switched to a refrigerant circuit that circulates through the heating unit, the outdoor pressure reducing unit, the outdoor heat absorbing unit, the accumulator, and the suction port of the compressor.

6. The outdoor pressure reducing unit and the outdoor heat absorbing unit form the recovery flow path. The heat pump cycle device according to claim 4 or 5, wherein in the liquid amount reduction control, the outside air decompression part is opened.

7. A discharge side branch part (12a) for branching the flow of the refrigerant discharged from the compressor, A heating part (13, 30) for heating an object to be heated using the refrigerant flowing out from one outlet of the discharge side branch part as a heat source, A bypass passage (21a) for circulating the refrigerant flowing out from the other outlet of the discharge side branch part, An equipment heat absorption part (20) for absorbing the equipment side heat generated by a heat generating equipment (70) that generates heat during operation by the refrigerant, and is provided with, The operation mode switching part has an equipment decompression part (14c) for decompressing the refrigerant flowing into the equipment heat absorption part (20), and a bypass side flow rate adjustment part (14d) for adjusting the flow rate of the refrigerant flowing through the bypass passage, The operation mode switching part, In the first operation mode, the refrigerant discharged from the compressor circulates in the order of the discharge side branch part, the heating part, the accumulator, and the suction port of the compressor, and is switched to a refrigerant circuit that circulates in the order of the discharge side branch part, the bypass passage, the accumulator, and the suction port of the compressor, The heat pump cycle device according to claim 1, wherein in the second operation mode, the refrigerant discharged from the compressor is switched to a refrigerant circuit that circulates in the order of the heating part, the equipment decompression part, the equipment heat absorption part, the accumulator, and the suction port of the compressor.

8. A discharge side branch part (12a) for branching the flow of the refrigerant discharged from the compressor, A heating part (13, 30a) for heating an object to be heated using the refrigerant flowing out from one outlet of the discharge side branch part as a heat source, A bypass passage (21a) for circulating the refrigerant flowing out from the other outlet of the discharge side branch part, A shared heat absorption unit (20) that causes the refrigerant to absorb at least one of the heat on the equipment side generated by the heat generating equipment (70) that generates heat during operation and the heat on the outside air side of the outside air. The operation mode switching unit includes a shared pressure reducing unit (14c) that reduces the pressure of the refrigerant flowing into the shared heat absorption unit, a bypass side flow rate adjusting unit (14d) that adjusts the flow rate of the refrigerant flowing through the bypass passage, and a heat absorption ratio adjusting unit (43) that adjusts the ratio of the outside air side heat and the equipment side heat in the heat that causes the refrigerant to absorb heat in the shared heat absorption unit. The operation mode switching unit In the first operation mode, the refrigerant discharged from the compressor circulates in the order of the discharge side branch portion, the heating unit, the accumulator, and the suction port of the compressor, and is switched to a refrigerant circuit that circulates in the order of the discharge side branch portion, the bypass passage, the accumulator, and the suction port of the compressor. Further, the heat absorption of the refrigerant in the shared heat absorption unit is stopped. In the second operation mode, the refrigerant discharged from the compressor is switched to a refrigerant circuit that circulates in the order of the heating unit, the shared pressure reducing unit, the shared heat absorption unit, the accumulator, and the suction port of the compressor. Further, at least one of the heat of the outside air and the heat generated by the heat generating equipment is absorbed by the refrigerant in the shared heat absorption unit. The heat pump cycle device according to claim 1.

9. A heating unit (13, 30a) that heats a heating object using the refrigerant discharged from the compressor as a heat source. A shared heat absorption unit (20) that causes the refrigerant to absorb at least one of the heat on the outside air side of the outside air and the heat on the equipment side generated by the heat generating equipment (70) that generates heat during operation. The operation mode switching unit includes a shared pressure reducing unit (14c) that reduces the pressure of the refrigerant flowing into the shared heat absorption unit, and a heat absorption ratio adjusting unit (43) that adjusts the ratio of the outside air side heat and the equipment side heat in the heat that causes the refrigerant to absorb heat in the shared heat absorption unit. The operation mode switching unit In the first operation mode, the refrigerant discharged from the compressor is switched to a refrigerant circuit that circulates in the order of the heating unit, the common decompression unit, the common heat absorption unit, the accumulator, and the suction port of the compressor. Further, the heat of the equipment side is absorbed by the refrigerant in the common heat absorption unit, The heat pump cycle device according to claim 1, wherein in the second operation mode, the refrigerant discharged from the compressor is switched to a refrigerant circuit that circulates in the order of the heating unit, the common decompression unit, the common heat absorption unit, the accumulator, and the suction port of the compressor. Further, the heat on the outside air side is absorbed by the refrigerant in the common heat absorption unit.

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