Refrigeration cycle device

Abstract

In a serial dehumidifying and space heating mode, this refrigeration cycle device switches to a refrigerant circuit in which a refrigerant discharged from a compressor (11) circulates in order through a heating unit (13, 40), an outdoor-side pressure reducing unit (14a), an outdoor heat exchanging unit (15), an indoor-side pressure reducing unit (14b), an indoor evaporating unit (18), and a suction inlet port of the compressor (11). Further, in a hot gas dehumidifying and space heating mode, the refrigeration cycle device switches to a refrigerant circuit in which the refrigerant discharged from a compressor (11) circulates in order through an upstream-side branching portion (12a), the heating unit (13, 40), the indoor-side pressure reducing unit (14b), the indoor evaporating unit (18), merging portions (12g, 12h), and the suction inlet opening of the compressor (11), and additionally circulates in order through the upstream-side branching portion (12a), the heating portion (13, 40), a bypass-side pressure reducing unit (14c), the merging portions (12g, 12h), and the suction inlet opening of the compressor (11), and circulates in order through the upstream-side branching portion (12a), a bypass passage (21c), the merging portions (12g, 12h), and the suction inlet port of the compressor (11).

Description

Refrigeration Cycle Equipment CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application is based on Japanese Patent Application No. 2022-142135 filed on September 7, 2022, the contents of which are incorporated herein by reference.

[0002] The present disclosure relates to a refrigeration cycle device applied to an air conditioner.

[0003] 2. Description of the Related Art Japanese Patent Application Laid-Open No. 2003-129999 discloses a refrigeration cycle device that is adapted to a vehicle air conditioner and is configured to be able to switch between operation modes.

[0004] The refrigeration cycle device of Patent Document 1 includes a heat pump cycle that adjusts the temperature of air blown into a vehicle interior, which is a space to be air-conditioned. The heat pump cycle of Patent Document 1 is configured to be able to switch refrigerant circuits depending on the operating mode in order to continuously adjust the temperature of the air blown over a wide range. For example, when dehumidifying and heating the vehicle interior, the refrigerant circuit switches between a series dehumidifying and heating mode and a parallel dehumidifying and heating mode.

[0005] More specifically, in the series dehumidifying and heating mode, the outdoor heat exchanger is switched to a refrigerant circuit connected in series upstream of the indoor evaporator in the refrigerant flow. The outdoor heat exchanger exchanges heat between the refrigerant and outdoor air. The indoor evaporator exchanges heat between the refrigerant and the ventilation air. In the series dehumidifying and heating mode, the amount of heat exchanged between the refrigerant and outdoor air in the outdoor heat exchanger is adjusted while suppressing frost formation on the indoor evaporator, thereby adjusting the heating capacity of the heating unit for the ventilation air.

[0006] In parallel dehumidifying and heating mode, the refrigerant circuit is switched to one in which the outdoor heat exchanger and the indoor evaporator are connected in parallel with respect to the refrigerant flow. The refrigerant evaporation temperature in the outdoor heat exchanger is lowered below that of the indoor evaporator while suppressing frost formation on the indoor evaporator. This increases the amount of heat absorbed by the refrigerant from the outside air, improving the heating capacity of the heater for the blown air compared to serial dehumidifying and heating mode.

[0007] In other words, in the vehicle air conditioning system of Patent Document 1, when dehumidifying and heating the passenger compartment, the refrigerant circuit is switched between a series dehumidifying and heating mode refrigerant circuit and a parallel dehumidifying and heating mode refrigerant circuit, allowing the temperature of the blown air to be continuously adjusted over a wide range.

[0008] JP 2012-225637 A

[0009] However, in the heat pump cycle of Patent Document 1, an evaporation pressure control valve is disposed downstream of the indoor evaporator in order to lower the refrigerant evaporation temperature in the outdoor heat exchanger below that of the indoor evaporator in parallel dehumidifying and heating mode. The evaporation pressure control valve increases the pressure loss of the refrigerant circulating through the heat pump cycle, which reduces the operating efficiency of the heat pump cycle.

[0010] In view of the above, an object of the present disclosure is to provide a refrigeration cycle device that can continuously adjust the temperature of blown air over a wide range while suppressing a decrease in operating efficiency.

[0011] A refrigeration cycle device according to a first aspect of the present disclosure includes a compressor, an upstream branch section, a heating section, a heating section-side pressure reducing section, an outdoor heat exchange section, an indoor evaporation section, a bypass passage, a bypass-side flow rate adjusting section, a confluence section, and a refrigerant circuit switching section.

[0012] The compressor compresses and discharges the refrigerant. The upstream branching section branches the flow of the refrigerant discharged from the compressor. The heating section uses the refrigerant flowing out from one outlet of the upstream branching section as a heat source to heat the air to be blown into the air-conditioned space. The heating section-side decompression section decompresses the refrigerant flowing out from the heating section. The outdoor heat exchange section exchanges heat between the refrigerant flowing out from the heating section-side decompression section and outside air. The indoor evaporating section evaporates the refrigerant decompressed by the heating section-side decompression section to cool the air to be heated by the heating section. The bypass passage guides the other refrigerant branched by the upstream branching section to the suction side of the compressor. The bypass-side flow rate adjustment section adjusts the flow rate of the refrigerant flowing through the bypass passage. The confluence section merges the flow of refrigerant flowing out from the heating section-side decompression section and the flow of refrigerant flowing out from the bypass-side flow rate adjustment section, and causes the refrigerant to flow out to the suction side of the compressor. The refrigerant circuit switching section switches the refrigerant circuit.

[0013] The heating unit-side pressure reduction section has an outdoor-side pressure reduction section, an indoor-side pressure reduction section, and a bypass-side pressure reduction section. The outdoor-side pressure reduction section reduces the pressure of refrigerant flowing into the outdoor heat exchange section. The indoor-side pressure reduction section reduces the pressure of refrigerant flowing into the indoor evaporator section. The bypass-side pressure reduction section reduces the pressure of refrigerant flowing bypassing the outdoor heat exchange section and the indoor evaporator section.

[0014] The air conditioner has a series dehumidifying and heating mode and a hot gas dehumidifying and heating mode as operation modes in which the blown air cooled in the indoor evaporating section is reheated in the heating section.

[0015] In the serial dehumidifying and heating mode, the refrigerant circuit switching unit switches to a refrigerant circuit in which the refrigerant discharged from the compressor circulates in the order of the heating unit, outdoor pressure reduction unit, outdoor heat exchange unit, indoor pressure reduction unit, indoor evaporator unit, and compressor intake.

[0016] In addition, in the hot gas dehumidifying heating mode, the refrigerant circuit switching unit switches to a refrigerant circuit in which the refrigerant discharged from the compressor circulates in the order of upstream branch section, heating section, indoor pressure reduction section, indoor evaporation section, junction section, and compressor suction port, and further in which the refrigerant discharged from the compressor circulates in the order of upstream branch section, heating section, bypass pressure reduction section, junction section, and compressor suction port, and in which the refrigerant discharged from the compressor circulates in the order of upstream branch section, bypass passage, junction section, and compressor suction port.

[0017] In the serial dehumidifying and heating mode, the throttle opening of at least one of the outdoor pressure reducing section and the indoor pressure reducing section can be adjusted to adjust the heat exchange rate between the refrigerant and the outdoor air in the outdoor heat exchange section while suppressing frost formation in the indoor evaporator, thereby continuously adjusting the heating capacity of the heating section.

[0018] In the hot gas dehumidifying and heating mode, the refrigerant with a relatively high enthalpy is merged with the refrigerant with a relatively low enthalpy flowing out from the bypass pressure reducing section through the bypass passage. This allows the amount of heat dissipated by the refrigerant in the heating section to be increased without reducing the refrigerant evaporation pressure in the indoor evaporation section when the refrigerant discharge capacity of the compressor is increased.

[0019] In other words, in the hot gas dehumidifying heating mode, by increasing the refrigerant discharge capacity of the compressor, it is possible to suppress frost formation in the indoor evaporator while improving the heating capacity of the blown air in the heating section more than in the serial dehumidifying heating mode.

[0020] Furthermore, in the hot gas dehumidifying and heating mode, the increased compression work that occurs when the refrigerant discharge capacity of the compressor is increased can be used as a heating source for the blown air, thereby preventing a decrease in operating efficiency when the heating capacity of the heater for the blown air is improved.

[0021] As a result, according to the refrigeration cycle device of the first aspect of the present disclosure, by switching between serial dehumidification heating mode and hot gas dehumidification heating mode, the temperature of the blown air can be continuously adjusted over a wide range while suppressing a decrease in operating efficiency.

[0022] Furthermore, a refrigeration cycle device according to a second aspect of the present disclosure includes a compressor, an upstream branch section, a heating section, a heating section side pressure reducing section, an outdoor heat exchange section, a bypass passage, a bypass side flow rate adjusting section, a confluence section, and a refrigerant circuit switching section.

[0023] The compressor compresses and discharges the refrigerant. The upstream branching section branches the flow of refrigerant discharged from the compressor. The heating section uses the refrigerant flowing out from one outlet of the upstream branching section as a heat source to heat the air to be blown into the air-conditioned space. The heating section side decompression section decompresses the refrigerant flowing out from the heating section. The outdoor heat exchange section exchanges heat between the refrigerant flowing out from the heating section side decompression section and outside air. The bypass passage guides the other refrigerant branched at the upstream branching section to the suction port side of the compressor. The bypass side flow rate adjustment section adjusts the flow rate of refrigerant flowing through the bypass passage. The confluence section merges the flow of refrigerant flowing out from the heating section side decompression section and the flow of refrigerant flowing out from the bypass side flow rate adjustment section, and causes the refrigerant to flow out to the suction port side of the compressor. The refrigerant circuit switching section switches the refrigerant circuit.

[0024] The heating unit-side pressure reduction section has an outdoor-side pressure reduction section and a bypass-side pressure reduction section. The outdoor-side pressure reduction section reduces the pressure of the refrigerant flowing into the outdoor heat exchange section. The bypass-side pressure reduction section reduces the pressure of the refrigerant bypassing the outdoor heat exchange section.

[0025] The operation modes for heating the blown air by the heating section include an outside air heat absorption heating mode and a hot gas heating mode.

[0026] In the outdoor air heat absorption heating mode, the refrigerant circuit switching unit switches to a refrigerant circuit in which refrigerant discharged from the compressor circulates through the heating unit, the outdoor pressure reducing unit, the outdoor heat exchange unit, and the compressor intake port in this order.

[0027] In addition, in the hot gas heating mode, the refrigerant circuit switching unit switches to a refrigerant circuit in which the refrigerant discharged from the compressor circulates in the order of the upstream branch section, heating section, bypass side pressure reduction section, junction section, and compressor suction port, and the refrigerant discharged from the compressor circulates in the order of the upstream branch section, bypass passage, junction section, and compressor suction port.

[0028] According to this, in the outdoor air heat absorption heating mode, the heating capacity of the heater for the blown air can be adjusted by adjusting at least one of the refrigerant discharge capacity of the compressor and the throttle opening of the outdoor pressure reducing section.

[0029] In the hot gas heating mode, the refrigerant with a relatively high enthalpy is merged with the refrigerant flowing out from the bypass pressure reduction section through the bypass passage. This allows the cycle to be balanced even if the refrigerant discharge capacity of the compressor is increased and the heating capacity of the heater section is improved.

[0030] Furthermore, in the hot gas heating mode, the increased compression work when the refrigerant discharge capacity of the compressor is increased can be used as a heating source for the blown air, thereby preventing a decrease in operating efficiency when the heating capacity of the heater for the blown air is improved.

[0031] As a result, according to the second aspect of the refrigeration cycle device of the present disclosure, by switching between the outdoor air heat absorption heating mode and the hot gas heating mode, the temperature of the blown air can be continuously adjusted over a wide range of temperatures while suppressing a decrease in operating efficiency.

[0032] The above and other objects, features, and advantages of the present disclosure will become more apparent from the following detailed description taken in conjunction with the accompanying drawings.

[0014] Fig. 1 is a schematic overall configuration diagram of a vehicle air conditioner of a first embodiment.

[0015] Fig. 2 is a block diagram of an electrical control unit of the vehicle air conditioner of the first embodiment.

[0016] Fig. 3 is a flowchart showing a part of the control process of the control program of the first embodiment.

[0017] Fig. 4 is a flowchart showing another part of the control process of the control program of the first embodiment.

[0018] Fig. 5 is a flowchart showing another part of the control process of the control program of the first embodiment.

[0019] Fig. 6 is a flowchart showing another part of the control process of the control program of the first embodiment.

[0020] Fig. 7 is a control characteristic diagram for switching an operation mode in the control program of the first embodiment.

[0021] Fig. 8 is another control characteristic diagram for switching an operation mode in the control program of the first embodiment.

[0022] Fig. 9 is another control characteristic diagram for switching an operation mode in the control program of the first embodiment.

[0023] Fig. 10 is a flowchart showing control process in an HG dehumidifying and heating mode of the control program of the first embodiment.

[0024] Fig. 11 is a schematic overall configuration diagram showing refrigerant flow and the like in the HG dehumidifying and heating mode and the cooled HG dehumidifying and heating mode of the vehicle air conditioner of the first embodiment. Fig. 1 is a Mollier diagram showing changes in refrigerant state in an HG dehumidifying heating mode of the heat pump cycle of the first embodiment. Fig. 2 is a flowchart showing control processing in an outside air heat absorption HG dehumidifying heating mode of the control program of the first embodiment. Fig. 3 is a schematic overall configuration diagram showing refrigerant flow, etc. in an outside air heat absorption HG dehumidifying heating mode and a cooled outside air heat absorption HG dehumidifying heating mode of the vehicle air conditioner of the first embodiment. Fig. 4 is a Mollier diagram showing changes in refrigerant state in an outside air heat absorption HG dehumidifying heating mode of the heat pump cycle of the first embodiment. Fig. 5 is a flowchart showing control processing in the HG heating mode of the control program of the first embodiment. Fig. 6 is a schematic overall configuration diagram showing refrigerant flow, etc. in an HG heating mode and a cooled HG heating mode of the vehicle air conditioner of the first embodiment.1 is a Mollier diagram showing a change in refrigerant state in the HG heating mode of the heat pump cycle of the first embodiment. FIG. 2 is a flowchart showing a control process in a cooling HG dehumidifying heating mode of the control program of the first embodiment. FIG. 3 is a Mollier diagram showing a change in refrigerant state in the cooling HG dehumidifying heating mode of the heat pump cycle of the first embodiment. FIG. 4 is a flowchart showing a control process in a cooling outside air heat absorption HG dehumidifying heating mode of the control program of the first embodiment. FIG. 5 is a Mollier diagram showing a change in refrigerant state in the cooling outside air heat absorption HG dehumidifying heating mode of the heat pump cycle of the first embodiment. FIG. 6 is a flowchart showing a control process in a cooling outside air heat absorption HG heating mode of the control program of the first embodiment. FIG. 7 is a Mollier diagram showing a change in refrigerant state in the cooling outside air heat absorption HG heating mode of the heat pump cycle of the first embodiment. FIG. 8 is a flowchart showing a control process in a cooling outside air heat absorption HG heating mode of the control program of the first embodiment. FIG. 9 is a schematic overall configuration diagram showing a refrigerant flow, etc., in the cooling outside air heat absorption HG heating mode of the vehicle air conditioner of the first embodiment. FIG. 10 is a Mollier diagram showing a change in refrigerant state in the cooling HG heating mode of the heat pump cycle of the first embodiment. 10 is another control characteristic diagram for switching operation modes in the control program of the second embodiment. FIG. 11 is a schematic overall configuration diagram of a vehicle air conditioner of a third embodiment. FIG. 12 is a schematic overall configuration diagram showing refrigerant flow, etc. in the HG dehumidifying heating mode and the cooled HG dehumidifying heating mode of the vehicle air conditioner of the third embodiment. FIG. 13 is a schematic overall configuration diagram showing refrigerant flow, etc. in the outside air heat absorption HG dehumidifying heating mode and the cooled outside air heat absorption HG dehumidifying heating mode of the vehicle air conditioner of the third embodiment. FIG. 14 is a schematic overall configuration diagram showing refrigerant flow, etc. in the HG heating mode and the cooled HG heating mode of the vehicle air conditioner of the third embodiment. FIG. 15 is a schematic overall configuration diagram showing refrigerant flow, etc. in the cooled outside air heat absorption HG heating mode of the vehicle air conditioner of the third embodiment.

[0033] Hereinafter, multiple embodiments for carrying out the present disclosure will be described with reference to the drawings. In each embodiment, parts corresponding to matters described in the preceding embodiment will be assigned the same reference numerals, and duplicate descriptions may be omitted. In each embodiment, when only a part of the configuration is described, other previously described embodiments may be applied to the other parts of the configuration. In addition to combinations of parts that are specifically specified as being combinable in each embodiment, it is also possible to partially combine embodiments even if not specified, as long as there is no particular problem with the combination.

[0034] First Embodiment A first embodiment of a refrigeration cycle device according to the present disclosure will now be described with reference to the drawings. In this embodiment, the refrigeration cycle device according to the present disclosure is applied to a vehicle air conditioner 1 mounted on an electric vehicle. An electric vehicle is a vehicle that obtains driving power for traveling from an electric motor. The vehicle air conditioner 1 of this embodiment conditions the interior of the vehicle, which is the space to be air-conditioned, and also regulates the temperature of on-board equipment, which is the object to be cooled. Therefore, the vehicle air conditioner 1 is an air conditioner with a function of regulating the temperature of on-board equipment.

[0035] Specifically, the vehicle air conditioner 1 regulates the temperature of a battery 70 as an on-board device. The battery 70 is a secondary battery that stores power to be supplied to a plurality of electrically operated on-board devices. The battery 70 is an assembled battery formed by electrically connecting a plurality of stacked battery cells 71 in series or parallel. In this embodiment, the battery cells 71 are lithium-ion batteries.

[0036] The battery 70 generates heat during operation (i.e., during charging and discharging). The output of the battery 70 is likely to decrease at low temperatures, and deterioration is likely to progress at high temperatures. For this reason, the temperature of the battery 70 needs to be maintained within an appropriate temperature range (in this embodiment, 15°C or higher and 55°C or lower). Therefore, in the electric vehicle of this embodiment, the temperature of the battery 70 is adjusted using the vehicle air conditioner 1.

[0037] As shown in the overall configuration diagram of FIG. 1, the vehicle air conditioner 1 includes a heat pump cycle 10, an interior air conditioning unit 30, a high-temperature side heat medium circuit 40, a low-temperature side heat medium circuit 50, and the like.

[0038] The heat pump cycle 10 constitutes a vapor compression refrigeration cycle for adjusting the temperatures of the blown air blown into the vehicle cabin, the high-temperature heat medium circulating through the high-temperature heat medium circuit 40, and the low-temperature heat medium circulating through the low-temperature heat medium circuit 50. The heat pump cycle 10 is configured to be able to switch refrigerant circuits according to various operation modes described below for air conditioning in the vehicle cabin and temperature adjustment of on-board equipment.

[0039] The heat pump cycle 10 employs an HFO refrigerant (specifically, R1234yf) as a refrigerant. The heat pump cycle 10 constitutes a vapor compression subcritical refrigeration cycle in which the pressure of the high-pressure side refrigerant does not exceed the critical pressure of the refrigerant. Refrigerant oil is mixed with the refrigerant to lubricate the compressor 11. In this embodiment, the refrigerant oil is a PAG oil that is compatible with liquid-phase refrigerants. A portion of the refrigerant oil circulates through the cycle together with the refrigerant.

[0040] The compressor 11 draws in, compresses, and discharges refrigerant in the heat pump cycle 10. The compressor 11 is an electric compressor that rotates a fixed-displacement compression mechanism with a fixed discharge capacity using an electric motor. The refrigerant discharge capacity (i.e., rotation speed) of the compressor 11 is controlled by a control signal output from a control device 60, which will be described later.

[0041] The compressor 11 is disposed in a drive unit compartment formed in the front side of the vehicle interior. The drive unit compartment forms a space in which at least some of the devices used to generate and adjust the driving force for running the vehicle (e.g., an electric motor for running the vehicle) are disposed.

[0042] The inlet side of a first three-way joint 12a is connected to the discharge port of the compressor 11. The first three-way joint 12a has three inlet and outlet ports that communicate with each other. The first three-way joint 12a may be a joint formed by joining multiple pipes or a joint formed by providing multiple refrigerant passages in a metal block or a resin block.

[0043] Furthermore, the heat pump cycle 10 includes a second three-way joint 12b to an eighth three-way joint 12h, as will be described later. The second three-way joint 12b to the eighth three-way joint 12h have the same basic configuration as the first three-way joint 12a. The basic configuration of each three-way joint described in the embodiments below is also the same as that of the first three-way joint 12a.

[0044] These three-way joints branch the refrigerant flow when one of the three inlet / outlet ports is used as an inlet and the remaining two are used as outlet ports. Furthermore, when two of the three inlet / outlet ports are used as inlet ports and the remaining one is used as an outlet port, the refrigerant flows are merged. The first three-way joint 12a is an upstream branching part that branches the flow of the refrigerant discharged from the compressor 11.

[0045] One outlet of the first three-way joint 12a is connected to the inlet side of the refrigerant passage of the water-refrigerant heat exchanger 13. The other outlet of the first three-way joint 12a is connected to one inlet side of a seventh three-way joint 12g.

[0046] The refrigerant passage extending from the other outlet of the first three-way joint 12a to one inlet of the seventh three-way joint 12g is a bypass passage 21c. A bypass-side flow rate adjustment valve 14d is disposed in the bypass passage 21c.

[0047] The bypass-side flow control valve 14d is a bypass-passage-side pressure reducing part that reduces the pressure of the refrigerant discharged from the other outlet of the first three-way joint 12a (i.e., the other refrigerant branched at the first three-way joint 12a) in a hot gas dehumidifying heating mode, etc., which will be described later. The bypass-side flow control valve 14d is also a bypass-side flow control part that adjusts the flow rate (mass flow rate) of the refrigerant flowing through the bypass passage 21c.

[0048] The bypass-side flow rate adjustment valve 14d is an electric variable throttle mechanism having a valve element that changes the throttle opening and an electric actuator that displaces the valve element. A stepping motor or a brushless motor can be used as the electric actuator. The operation of the bypass-side flow rate adjustment valve 14d is controlled by a control signal output from the control device 60.

[0049] The bypass-side flow control valve 14d has a full-open function that functions simply as a refrigerant passage without exerting any refrigerant pressure reduction or flow rate adjustment functions by fully opening the throttle, and a full-close function that closes the refrigerant passage by fully closing the throttle.

[0050] Furthermore, as will be described later, the heat pump cycle 10 includes a heating expansion valve 14 a, a cooling expansion valve 14 b, and a cooling expansion valve 14 c. The heating expansion valve 14 a, the cooling expansion valve 14 b, and the cooling expansion valve 14 c have the same basic configuration as the bypass-side flow control valve 14 d.

[0051] 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 of the heat pump cycle 10 by performing the above-mentioned fully closing function. 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 also function as a refrigerant circuit switching unit.

[0052] Of course, the heating expansion valve 14 a, the cooling expansion valve 14 b, the cooling expansion valve 14 c, and the bypass side flow control valve 14 d may be formed by combining a variable throttle mechanism that does not have a full-closing function with an on-off valve that opens and closes the throttle passage. In this case, each on-off valve serves as a refrigerant circuit switching unit.

[0053] The water-refrigerant heat exchanger 13 is a high-temperature side heat exchange unit that exchanges heat between the discharged refrigerant flowing out from one outlet of the first three-way joint 12a (i.e., one of the refrigerants branched at the first three-way joint 12a) and the high-temperature side heat medium circulating through the high-temperature side heat medium circuit 40. The water-refrigerant heat exchanger 13 is a refrigerant heat dissipation unit that dissipates heat from the discharged refrigerant to the high-temperature side heat medium to heat the high-temperature side heat medium.

[0054] An inlet side of a second three-way joint 12b is connected to the outlet of the refrigerant passage of the water-refrigerant heat exchanger 13. One outlet side of the second three-way joint 12b is connected to the refrigerant inlet side of the outdoor heat exchanger 15. The other outlet side of the second three-way joint 12b is connected to one inlet side of a fourth three-way joint 12d.

[0055] The refrigerant passage extending from the other outlet of the second three-way joint 12b to one inlet of the fourth three-way joint 12d is a high-pressure side passage 21a. A high-pressure side on-off valve 22a is arranged in the high-pressure side passage 21a.

[0056] The high-pressure side on-off valve 22a is an on-off valve that opens and closes the high-pressure side passage 21a. The high-pressure side 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 high-pressure side on-off valve 22a can switch the refrigerant circuit by opening and closing the high-pressure side passage 21a. Therefore, the high-pressure side on-off valve 22a is a refrigerant circuit switching unit.

[0057] A heating expansion valve 14a is disposed in the refrigerant passage extending from one outlet of the second three-way joint 12b to the refrigerant inlet of the outdoor heat exchanger 15. The heating expansion valve 14a is an outdoor-side pressure reducing unit that reduces the pressure of the refrigerant flowing into the outdoor heat exchanger 15, for example, in an outdoor air heat absorption heating mode (described later). The heating expansion valve 14a also serves as an outdoor-side flow rate adjusting unit that adjusts the flow rate (mass flow rate) of the refrigerant flowing into the outdoor heat exchanger 15.

[0058] The exterior heat exchanger 15 is an exterior heat exchanger that exchanges heat between the refrigerant flowing out of the heating expansion valve 14a and outside air blown in by an outside air fan (not shown). The exterior heat exchanger 15 is located on the front side of the drive unit compartment. Therefore, when the vehicle is running, the airflow that flows into the drive unit compartment through the grille can hit the exterior heat exchanger 15.

[0059] An inlet side of a third three-way joint 12c is connected to a refrigerant outlet of the outdoor heat exchanger 15. One outlet side of the third three-way joint 12c is connected to the other inlet side of a fourth three-way joint 12d. One outlet side of the third three-way joint 12c is connected to one inlet side of an eighth three-way joint 12h.

[0060] The refrigerant passage extending from the other outlet of the third three-way joint 12c to one inlet of the eighth three-way joint 12h is a low-pressure side passage 21b, which includes a low-pressure side on-off valve 22b and a first check valve 16a.

[0061] The low-pressure side on-off valve 22b is an on-off valve that opens and closes the low-pressure side passage 21b. The basic configuration of the low-pressure side on-off valve 22b is the same as that of the high-pressure side on-off valve 22a. Therefore, the low-pressure side on-off valve 22b is a refrigerant circuit switching unit. The first check valve 16a allows refrigerant to flow from the third three-way joint 12c to the eighth three-way joint 12h and prohibits refrigerant from flowing from the eighth three-way joint 12h to the third three-way joint 12c.

[0062] A second check valve 16b is disposed in the refrigerant passage extending from one outlet of the third three-way joint 12c to the other inlet of the fourth three-way joint 12d. The second check valve 16b allows the refrigerant to flow from the third three-way joint 12c to the fourth three-way joint 12d, but prevents the refrigerant from flowing from the fourth three-way joint 12d to the third three-way joint 12c.

[0063] The outlet of the fourth three-way joint 12 d is connected to the inlet side of a fifth three-way joint 12 e. One outlet of the fifth three-way joint 12 e is connected to the refrigerant inlet side of the indoor evaporator 18. The other outlet of the fifth three-way joint 12 e is connected to the refrigerant inlet side of the chiller 20.

[0064] A cooling expansion valve 14b is disposed in the refrigerant passage extending from one outlet of the fifth three-way joint 12e to the refrigerant inlet of the indoor evaporator 18. The cooling expansion valve 14b is an indoor pressure reducing unit that reduces the pressure of the refrigerant flowing out from one outlet of the fifth three-way joint 12e during a single cooling mode, which will be described later, etc. The cooling expansion valve 14b also serves as an indoor flow rate adjusting unit that adjusts the flow rate (mass flow rate) of the refrigerant flowing into the indoor evaporator 18.

[0065] The interior evaporator 18 is disposed in an air conditioning case 31 of the interior air conditioning unit 30, which will be described later. The interior evaporator 18 is an air cooling heat exchanger that exchanges heat between the low-pressure refrigerant decompressed by the cooling expansion valve 14b and the blown air blown into the vehicle cabin from the interior blower 32. The interior evaporator 18 is an interior evaporation section that cools the blown air by evaporating the low-pressure refrigerant and exerting a heat absorption effect.

[0066] One inlet side of a sixth three-way joint 12f is connected to the refrigerant outlet of the interior evaporator 18. A third check valve 16c is disposed in the refrigerant passage extending from the refrigerant outlet of the interior evaporator 18 to one inlet side of the sixth three-way joint 12f. The third check valve 16c allows refrigerant to flow from the interior evaporator 18 side to the sixth three-way joint 12f side, but prohibits refrigerant from flowing from the sixth three-way joint 12f side to the interior evaporator 18 side.

[0067] A cooling expansion valve 14c is disposed in the refrigerant passage extending from the other outlet of the fifth three-way joint 12e to the refrigerant inlet of the chiller 20. The cooling expansion valve 14c is a cooling-side pressure reducing unit that reduces the pressure of the refrigerant flowing out from the other outlet of the fifth three-way joint 12e during a cooling mode, which will be described later, etc. The cooling expansion valve 14c is also a cooling-side flow rate adjusting unit that adjusts the flow rate (mass flow rate) of the refrigerant flowing into the chiller 20.

[0068] Furthermore, the cooling expansion valve 14c serves as a bypass pressure reducing section that reduces the pressure of the refrigerant that flows bypassing the outdoor heat exchanger 15 and the indoor evaporator 18 during a hot gas dehumidifying heating mode, which will be described later.

[0069] The chiller 20 is a low-temperature side heat exchange unit that exchanges heat between the low-pressure refrigerant decompressed by the cooling expansion valve 14c and the low-temperature side heat medium circulating through the low-temperature side heat medium circuit 50. The chiller 20 is a cooling evaporation unit that cools the low-temperature side heat medium by evaporating the low-pressure refrigerant to exert a heat absorption effect.

[0070] The other inlet side of the sixth three-way joint 12f is connected to the refrigerant outlet of the chiller 20. The other inlet side of the seventh three-way joint 12g is connected to the outlet side of the sixth three-way joint 12f. The other inlet side of the eighth three-way joint 12h is connected to the outlet side of the seventh three-way joint 12g.

[0071] The outlet of the eighth three-way joint 12h is connected to the inlet side of the accumulator 23. The accumulator 23 is a low-pressure gas-liquid separator that separates the refrigerant that flows into it into gas and liquid phases and stores the separated liquid-phase refrigerant as surplus refrigerant for the cycle. The gas-phase refrigerant outlet of the accumulator 23 is connected to the suction port side of the compressor 11.

[0072] As is clear from the above description, the seventh three-way joint 12g and the eighth three-way joint 12h join the refrigerant flowing out from the heating expansion valve 14a, the cooling expansion valve 14b, and the cooling expansion valve 14c with the flowing out from the bypass-side flow control valve 14d. The seventh three-way joint 12g and the eighth three-way joint 12h then function as a joining section that allows the joined refrigerant to flow into the suction port side of the compressor 11.

[0073] Next, the high-temperature side heat medium circuit 40 will be described. The high-temperature side heat medium circuit 40 is a heat medium circulation circuit that circulates the high-temperature side heat medium. In this embodiment, an ethylene glycol aqueous solution is used as the high-temperature side heat medium. The high-temperature side heat medium circuit 40 includes a heat medium passage of the water-refrigerant heat exchanger 13, a high-temperature side pump 41, a heater core 42, and the like.

[0074] The high-temperature side pump 41 is a high-temperature side heat medium pumping unit that pumps the high-temperature side heat medium to the inlet side of the heat medium passage of the water-refrigerant heat exchanger 13. The high-temperature side pump 41 is an electric water pump whose rotation speed (i.e., pumping capacity) is controlled by a control voltage output from the control device 60.

[0075] The heat medium inlet side of a heater core 42 is connected to the outlet of the heat medium passage of the water-refrigerant heat exchanger 13. The heater core 42 is an air heating heat exchange unit that exchanges heat between the high-temperature side heat medium heated in the water-refrigerant heat exchanger 13 and the blown air that has passed through the indoor evaporator 18. The heater core 42 is a heat medium radiating unit that radiates heat from the high-temperature side heat medium to the blown air, thereby heating the blown air.

[0076] The heater core 42 is disposed in the air conditioning case 31 of the interior air conditioning unit 30. The outlet of the heat medium passage of the heater core 42 is connected to the intake port side of the high temperature side pump 41.

[0077] Therefore, the water-refrigerant heat exchanger 13 and the components of the high-temperature side heat medium circuit 40 of this embodiment form a heating section that heats the air to be blown into the vehicle cabin using the refrigerant flowing out from one outlet of the first three-way joint 12 a as a heat source. Furthermore, the heating expansion valve 14 a, the cooling expansion valve 14 b, and the cooling expansion valve 14 c are all included in a heating section-side decompression section that decompresses the refrigerant flowing out from the water-refrigerant heat exchanger 13 that forms the heating section.

[0078] Next, the low-temperature side heat medium circuit 50 will be described. The low-temperature side heat medium circuit 50 is a heat medium circulation circuit that circulates the low-temperature side heat medium. In this embodiment, the same type of fluid as the high-temperature side heat medium is used as the low-temperature side heat medium. The low-temperature side heat medium circuit 50 includes a heat medium passage for the chiller 20, a low-temperature side pump 51, a coolant passage 70a for the battery 70, a heat medium three-way valve 53, a low-temperature side radiator 54, and the like.

[0079] The low-temperature side pump 51 is a low-temperature side heat medium pumping unit that pumps the low-temperature side heat medium to the inlet side of the heat medium passage of the chiller 20. The basic configuration of the low-temperature side pump 51 is similar to that of the high-temperature side pump 41.

[0080] The outlet of the heat medium passage of the chiller 20 is connected to the inlet side of the coolant passage 70a of the battery 70. The coolant passage 70a of the battery 70 is a coolant passage that cools the battery 70 by circulating the low-temperature heat medium that has flowed out from the chiller 20. In other words, the coolant passage 70a is a heat exchanger for cooling the battery 70 by exchanging heat between the low-temperature heat medium circulating through the heat medium flow path and the battery cells 71.

[0081] The cooling water passages 70a are formed inside a battery case that houses a plurality of stacked battery cells 71. The cooling water passages 70a are configured so that multiple passages are connected in parallel inside the battery case, allowing the cooling water passages 70a to cool all of the battery cells 71 evenly.

[0082] The inlet side of the heat medium three-way valve 53 is connected to the outlet of the coolant passage 70a of the battery 70. The heat medium three-way valve 53 is an electric three-way flow control valve that has one inlet and two outlets and can continuously adjust the passage area ratio of the two outlets. The operation of the heat medium three-way valve 53 is controlled by a control signal output from the control device 60.

[0083] One outlet of the heat medium three-way valve 53 is connected to the heat medium inlet side of the low-temperature side radiator 54. The other outlet of the heat medium three-way valve 53 is connected to one inlet side of a heat medium three-way joint 55. The basic configuration of the heat medium three-way joint 55 is similar to that of the first three-way joint 12a for the refrigerant, etc.

[0084] The low-temperature side radiator 54 is an outside air heat exchanger for a heat medium that exchanges heat between the refrigerant flowing out of the coolant passage 70a and outside air blown by an outside air fan (not shown). The low-temperature side radiator 54 is disposed at the front side of the drive unit compartment. Therefore, when the vehicle is traveling, traveling air can be applied to the low-temperature side radiator 54. The low-temperature side radiator 54 may be formed integrally with the exterior heat exchanger 15.

[0085] The heat medium outlet of the low-temperature side radiator 54 is connected to the other inlet side of the heat medium three-way joint 55. The outlet side of the heat medium three-way joint 55 is connected to the suction side of the low-temperature side pump 51.

[0086] Therefore, the chiller 20 and the components of the low-temperature side heat medium circuit 50 in this embodiment are a cooling unit that cools the battery 70, which is the object to be cooled, using the low-temperature side heat medium flowing out from the heat medium passage of the chiller 20.

[0087] In the cooling section of the present embodiment, the heat medium three-way valve 53 allows the low-temperature side heat medium flowing out from the coolant passage 70a to flow into the heat medium passage of the chiller 20. As a result, the heat absorbed from the battery 70 by the low-temperature side heat medium in the coolant passage 70a can be absorbed by the low-pressure refrigerant in the chiller 20.

[0088] Furthermore, in the cooling section of this embodiment, the heat medium three-way valve 53 allows the low-temperature side heat medium that flows out from the coolant passage 70a to flow into the low-temperature side radiator 54. This allows the low-temperature side heat medium that absorbs heat from the battery 70 in the coolant passage 70a to be radiated to the outside air by the low-temperature side radiator 54.

[0089] Next, the interior air conditioning unit 30 will be described. The interior air conditioning unit 30 is an air distribution unit that integrates multiple components to blow air adjusted to an appropriate temperature to appropriate locations within the vehicle cabin. The interior air conditioning unit 30 is located inside the instrument panel at the front of the vehicle cabin.

[0090] 1, the indoor air conditioning unit 30 is formed by accommodating an indoor fan 32, an indoor evaporator 18, a heater core 42, etc. in an air conditioning case 31 that forms an air passage for blown air. The air conditioning case 31 is molded from a resin (e.g., polypropylene) that has a certain degree of elasticity and excellent strength.

[0091] An inside / outside air switching device 33 is disposed on the most upstream side of the blown air flow of the air conditioning case 31. The inside / outside air switching device 33 switches between introducing inside air (i.e., air inside the vehicle cabin) and outside air (i.e., air outside the vehicle cabin) into the air conditioning case 31. The operation of the inside / outside air switching device 33 is controlled by a control signal output from the control device 60.

[0092] An interior blower 32 is disposed downstream of the inside / outside air switching device 33 in the flow of blown air. The interior blower 32 is an interior blower unit that blows air drawn in through the inside / outside air switching device 33 toward the vehicle interior. The rotation speed (i.e., blowing capacity) of the interior blower 32 is controlled by a control voltage output from the control device 60.

[0093] The interior evaporator 18 and the heater core 42 are disposed downstream in the flow of air blown by the interior blower 32. The interior evaporator 18 is disposed upstream in the flow of air blown from the heater core 42. A cool air bypass passage 35 is formed in the air conditioning case 31, allowing the air blown after passing through the interior evaporator 18 to bypass the heater core 42.

[0094] An air mix door 34 is disposed downstream of the interior evaporator 18 in the air conditioning case 31 in the direction of the blown air flow, and upstream of the heater core 42 and the cool air bypass passage 35 in the direction of the blown air flow.

[0095] The air mix door 34 is an air volume ratio adjusting unit that adjusts the ratio of the volume of the blown air that passes through the heater core 42 side to the volume of the blown air that passes through the cool air bypass passage 35 after passing through the interior evaporator 18. The operation of the actuator for driving the air mix door 34 is controlled by a control signal output from the control device 60.

[0096] A mixing space 36 is formed downstream of the heater core 42 and the cold air bypass passage 35 in the air conditioning case 31 in the direction of the blown air flow. The mixing space 36 is a space where the blown air heated by the heater core 42 mixes with the blown air that has passed through the cold air bypass passage 35 and has not been heated.

[0097] Therefore, in the interior air conditioning unit 30, the air mix door 34 adjusts the air volume ratio, thereby adjusting the temperature of the blown air (i.e., conditioned air) that is mixed in the mixing space 36 and blown into the vehicle interior.

[0098] Furthermore, an opening hole is arranged downstream of the airflow of the air conditioning case 31 for blowing the air that has been mixed and temperature-adjusted in the mixing space into the vehicle interior.

[0099] The openings include a face opening, a foot opening, and a defroster opening (none of which are shown). The face opening is an opening for blowing conditioned air toward the upper bodies of occupants in the vehicle cabin. The foot opening is an opening for blowing conditioned air toward the feet of occupants. The defroster opening is an opening for blowing conditioned air toward the inside surface of the vehicle front windshield.

[0100] Additionally, a face door, a foot door, and a defroster door (none of which are shown) are disposed upstream of the face opening, foot opening, and defroster opening, respectively. The face door adjusts the opening area of ​​the face opening. The foot door adjusts the opening area of ​​the foot opening. The defroster door adjusts the opening area of ​​the defroster opening.

[0101] The face door, foot door, and defroster door are air outlet mode switching units that switch the air outlet mode. These doors are connected to a common electric actuator for driving the air outlet mode doors via a link mechanism or the like, and are rotated in conjunction with each other. The operation of the electric actuator for driving the air outlet mode doors is controlled by a control signal output from the control device 60.

[0102] Therefore, in the interior air conditioning unit 30, by switching the opening hole that the air outlet mode switching section opens and closes to switch the air outlet mode, air conditioned air adjusted to an appropriate temperature can be blown out from the mixing space 36 to an appropriate location in the vehicle cabin.

[0103] Next, an overview of the electrical control unit of this embodiment will be described. The control device 60 is composed of a well-known microcomputer including a CPU, ROM, RAM, etc., and its peripheral circuits. It performs various calculations and processes based on control programs stored in the ROM, and controls the operation of the various control target devices 11, 14a to 14d, 22a, 22b, 32, 41, 51, 53, etc. connected to its output side.

[0104] As shown in the block diagram of Figure 2, a group of control sensors is connected to the input side of the control device 60. Detection signals from the group of control sensors are input to the control device 60. Each sensor will be described below.

[0105] The inside air temperature sensor 61a is an inside air temperature detector that detects the temperature inside the vehicle cabin (inside air temperature) Tr. The outside air temperature sensor 61b is an outside air temperature detector that detects the temperature outside the vehicle cabin (outside air temperature) Tam. The solar radiation sensor 61c is an solar radiation amount detector that detects the amount of solar radiation As irradiating the vehicle cabin.

[0106] The discharge refrigerant temperature and pressure sensor 62 a is a discharge refrigerant temperature and pressure detection unit that detects the discharge refrigerant temperature Td and the discharge refrigerant pressure Pd of the discharge refrigerant discharged from the compressor 11 .

[0107] The high-pressure side refrigerant temperature and pressure sensor 62 b 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-refrigerant heat exchanger 13 .

[0108] The outdoor unit side refrigerant temperature and pressure sensor 62 c is an outdoor unit side refrigerant temperature and pressure detection unit that detects the outdoor unit side refrigerant temperature T2 and outdoor unit side refrigerant pressure P2 of the refrigerant flowing out from the outdoor heat exchanger 15 .

[0109] The evaporator-side refrigerant temperature and pressure sensor 62 d is an evaporator-side refrigerant temperature and pressure detection unit that detects the evaporator-side refrigerant temperature Te and evaporator-side refrigerant pressure Pe of the refrigerant flowing out from the interior evaporator 18 .

[0110] The chiller-side refrigerant temperature and pressure sensor 62 e is a chiller-side refrigerant temperature and pressure detection unit that detects the chiller-side refrigerant temperature Tc and chiller-side refrigerant pressure Pc of the refrigerant flowing out from the refrigerant passage of the chiller 20 .

[0111] In this embodiment, a detection unit in which a pressure detection unit and a temperature detection unit are integrated is used as the refrigerant temperature pressure sensor, but of course, a pressure detection unit and a temperature detection unit that are each configured as separate units may also be used.

[0112] The evaporator temperature sensor 62f is an evaporator temperature detection unit that detects the refrigerant evaporation temperature (evaporator temperature) Tefin in the interior evaporator 18. Specifically, the evaporator temperature sensor 62f in this embodiment detects the temperature of the heat exchange fins of the interior evaporator 18.

[0113] 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 that flows out of the heat medium passage of the water-refrigerant heat exchanger 13 and into the heater core 42.

[0114] The first low-temperature-side heat medium temperature sensor 64a is a first low-temperature-side heat medium temperature detector that detects a first low-temperature-side heat medium temperature TWL1, which is the temperature of the low-temperature-side heat medium flowing into the coolant passage 70a. The second low-temperature-side heat medium temperature sensor 64b is a second low-temperature-side heat medium temperature detector that detects a second low-temperature-side heat medium temperature TWL2, which is the temperature of the low-temperature-side heat medium flowing out of the coolant passage 70a.

[0115] The battery temperature sensor 65 is a battery temperature detection unit that detects the battery temperature TB, which is the temperature of the battery 70. The battery temperature sensor 65 has multiple temperature sensors and detects the temperature at multiple locations on the battery 70. This allows the control device 60 to detect the temperature difference and temperature distribution among the battery cells that make up the battery 70. Furthermore, the average value of the detected values ​​from the multiple temperature sensors is used as the battery temperature TB.

[0116] The air conditioning air temperature sensor 66 is an air conditioning air temperature detection unit that detects the blown air temperature TAV, which is the temperature of the blown air blown into the vehicle interior from the mixing space 36. The intake air temperature sensor 67 is an intake air temperature detection unit that detects the intake air temperature Tin, which is the temperature of the blown air flowing into the interior evaporator 18.

[0117] 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 are input to the control device 60 from various operation switches provided on the operation panel 69.

[0118] The various operation switches provided on the operation panel 69 specifically include an auto switch, an air conditioner switch, an air volume setting switch, a temperature setting switch, an air outlet mode switch, and the like.

[0119] The auto switch is an automatic control setting unit that sets or cancels automatic control operation of the vehicle air conditioner 1. The air conditioner switch is a cooling request unit that requests cooling of the blown air by the interior evaporator 18. The air volume setting switch is an air volume setting unit that manually sets the blown air volume of the interior blower 32. The temperature setting switch is a temperature setting unit that sets the interior set temperature Tset. The air outlet mode switch is an air outlet mode setting unit that manually sets the air outlet mode.

[0120] The control device 60 of this embodiment is an integrated unit that controls various control target devices connected to its output side. Therefore, the configuration (hardware and software) that controls the operation of each control target device constitutes the control unit that controls the operation of each control target device.

[0121] For example, in the control device 60, the component that controls the rotation speed of the compressor 11 constitutes a discharge capacity control unit 60a, and the component that controls the operation of the refrigerant circuit switching units, such as the high-pressure side on-off valve 22a and the low-pressure side on-off valve 22b, constitutes a refrigerant circuit switching control unit 60b.

[0122] Next, the operation of the present embodiment with the above configuration will be described. As described above, the automotive air conditioner 1 of this embodiment conditions the air inside the vehicle cabin and also regulates the temperature of the battery 70. To achieve this, the automotive air conditioner 1 can execute the following 16 operating modes.

[0123] (1) Single cooling mode: The single cooling mode is included in the cooling modes in which the vehicle cabin is cooled by cooling the blown air and blowing it into the vehicle cabin. The single cooling mode is an operating mode in which the vehicle cabin is cooled without cooling the battery 70.

[0124] (2) Series dehumidifying and heating mode: The series dehumidifying and heating mode is included in the dehumidifying and heating mode in which cooled and dehumidified ventilation air is reheated and blown into the passenger compartment to dehumidify and heat the passenger compartment. The series dehumidifying and heating mode is an operating mode in which the passenger compartment is dehumidified and heated without cooling the battery 70.

[0125] (3-1) Hot gas dehumidifying and heating mode (hereinafter referred to as HG dehumidifying and heating mode): The HG dehumidifying and heating mode is included in the dehumidifying and heating mode. The HG dehumidifying and heating mode is an operation mode that dehumidifies and heats the vehicle cabin with a heating capacity higher than that of the series dehumidifying and heating mode without cooling the battery 70.

[0126] (3-2) Outside air heat absorption hot gas dehumidifying heating mode (hereinafter referred to as outside air heat absorption HG dehumidifying heating mode): The outside air heat absorption HG dehumidifying heating mode is included in the dehumidifying heating mode. The outside air heat absorption HG dehumidifying heating mode is an operating mode that dehumidifies and heats the vehicle interior with a heating capacity higher than that of the series dehumidifying heating mode and with an operating efficiency higher than that of the HG dehumidifying heating mode, without cooling the battery 70.

[0127] (4-1) Outside Air Heating Mode: The outside air heating mode is included in the heating modes in which the vehicle interior is heated by heating the ventilation air and blowing it into the vehicle interior. The outside air heating mode is an operating mode in which the vehicle interior is heated without cooling the battery 70.

[0128] (4-2) Hot gas heating mode (hereinafter referred to as HG heating mode): The HG heating mode is included in the heating mode. The HG heating mode is an operation mode in which the vehicle interior is heated with a heating capacity higher than that in the outside air heat absorption heating mode without cooling the battery 70.

[0129] (5) Cooling / Cooling Mode: The cooling / cooling mode is included in the cooling mode. The cooling / cooling mode is an operation mode in which the battery 70 is cooled and the interior of the vehicle is cooled.

[0130] (6) Cooling-series dehumidifying and heating mode: The cooling-series dehumidifying and heating mode is included in the dehumidifying and heating mode. The cooling-series dehumidifying and heating mode is an operation mode in which the battery 70 is cooled and the vehicle interior is dehumidified and heated.

[0131] (7-1) Cooled hot gas dehumidifying and heating mode (hereinafter referred to as the cooled hot gas dehumidifying and heating mode): The cooled hot gas dehumidifying and heating mode is included in the dehumidifying and heating mode. The cooled hot gas dehumidifying and heating mode is an operation mode that cools the battery 70 and dehumidifies and heats the vehicle interior with a heating capacity higher than that of the cooled series dehumidifying and heating mode.

[0132] (7-2) Cooled outdoor air heat absorption hot gas dehumidifying heating mode (hereinafter referred to as cooled outdoor air heat absorption HG dehumidifying heating mode): The cooled outdoor air heat absorption HG dehumidifying heating mode is included in the dehumidifying heating mode. The cooled outdoor air heat absorption HG dehumidifying heating mode is an operating mode that cools the battery 70 and dehumidifies and heats the vehicle cabin with a heating capacity higher than that of the cooled series dehumidifying heating mode and with an operating efficiency higher than that of the cooled HG dehumidifying heating mode.

[0133] (8) Refrigeration device heat absorption heating mode: The cooling device heat absorption heating mode is included in the heating mode. The cooling device heat absorption heating mode is an operation mode in which the battery 70 is cooled and the vehicle interior is heated by utilizing waste heat absorbed from the battery 70 by the refrigerant.

[0134] (9) Cooled Outside Air Heat Endoscopy Heating Mode: The cooled outside air heat endoscopy heating mode is included in the heating mode. The cooled outside air heat endoscopy heating mode is an operation mode in which the battery 70 is cooled and the vehicle interior is heated by utilizing heat absorbed by the refrigerant from the outside air.

[0135] (10-1) Cooled hot gas heating mode (hereinafter referred to as cooled hot gas heating mode): The cooled hot gas heating mode is included in the heating mode. The cooled hot gas heating mode is an operation mode that cools the battery 70 and heats the vehicle interior with a heating capacity higher than that of the cooled outside air heat absorption heating mode.

[0136] (10-2) Cooled outside air heat absorption hot gas heating mode (hereinafter referred to as cooled outside air heat absorption HG heating mode): The cooled outside air heat absorption HG heating mode is included in the heating mode. The cooled outside air heat absorption HG heating mode is an operation mode that cools the battery 70 and heats the vehicle interior with a heating capacity higher than that of the cooled outside air heat absorption heating mode and with an operating efficiency higher than that of the cooled outside air heat absorption heating mode.

[0137] (11) Cooling mode: This is an operating mode in which the battery 70 is cooled without air conditioning the interior of the vehicle.

[0138] (12) Fan mode: This is an operating mode in which ventilation air is blown into the vehicle interior without cooling the battery 70 or adjusting the temperature of the air conditioning air.

[0139] These driving modes are switched by executing a control program stored in advance in the control device 60. The control program is executed not only when the start switch (so-called ignition switch) of the vehicle system is turned on and the vehicle system is running, but also when the battery 70 is being charged from an external power source, etc. The control program performs air conditioning in the vehicle cabin when the auto switch is turned on.

[0140] The control program will be described with reference to Fig. 3 etc. Each control step shown in the flowchart of Fig. 3 etc. is a part that realizes various functions of the control device 60.

[0141] 3, the detection signals from the above-mentioned sensors and the operation signal from the operation panel 69 are read. Next, in step S20, a target blowout temperature TAO, which is the target temperature of the air blown into the vehicle compartment, is determined based on the detection signals and the operation signal read in step S10. Therefore, step S20 is a target blowout temperature determining section.

[0142] Specifically, the target air temperature TAO is calculated by the following formula F1: TAO=Kset×Tset−Kr×Tr−Kam×Tam−Ks×As+C (F1) Tset is the interior temperature set by the temperature setting switch. Tr is the interior temperature detected by the interior temperature sensor 61a. Tam is the outside temperature detected by the outside temperature sensor 61b. As is the amount of solar radiation detected by the solar radiation sensor 61c. Kset, Kr, Kam, and Ks are control gains, and C is a correction constant.

[0143] Next, in step S30, it is determined whether the air conditioner switch is ON (turned on). As described above, the air conditioner switch is a cooling request unit that requests cooling of the blown air by the interior evaporator 18. Therefore, when the air conditioner switch is ON, it means that the occupant is requesting cooling or dehumidifying heating of the vehicle interior.

[0144] If it is determined in step S30 that the air conditioner switch is ON, the process proceeds to step S40. If it is determined in step S30 that the air conditioner switch is not ON, the process proceeds to step S200.

[0145] In step S40, it is determined whether the outside air temperature Tam is higher than a predetermined reference outside air temperature KA (0° C. in this embodiment). The reference outside air temperature KA is set so that cooling the blown air by the indoor evaporator 18 is effective for cooling or dehumidifying the space to be air-conditioned.

[0146] More specifically, in this embodiment, in an operation mode in which the refrigerant is evaporated in the interior evaporator 18, the refrigerant evaporation temperature in the interior evaporator 18 is adjusted to be equal to or higher than the frost suppression temperature (1° C. in this embodiment) that can suppress frost formation on the interior evaporator 18. Therefore, the interior evaporator 18 cannot cool the blown air to a temperature lower than the frost suppression temperature.

[0147] That is, when the temperature of the blown air flowing into the interior evaporator 18 is lower than the frost suppression temperature, it is not effective to cool the blown air by the interior evaporator 18. Therefore, the reference outside air temperature KA is set to a value lower than the frost suppression temperature, and when the outside air temperature Tam is equal to or lower than the reference outside air temperature KA, the blown air is not cooled by the interior evaporator 18.

[0148] If it is determined in step S40 that the outside air temperature Tam is higher than the reference outside air temperature KA, the process proceeds to step S50. If it is determined in step S40 that the outside air temperature Tam is not higher than the reference outside air temperature KA, the process proceeds to step S200.

[0149] In step S50, it is determined whether the target air temperature TAO is lower than a reference air-conditioning temperature α1. The reference air-conditioning temperature α1 is a reference value for determining whether or not to cool the vehicle interior. The reference air-conditioning temperature α1 is determined based on the outside air temperature Tam and by referring to a control map stored in advance in the control device 60.

[0150] In the control map of this embodiment, as shown in Fig. 8, the cooling reference temperature α1 is determined to a lower value as the outside air temperature Tam decreases. Fig. 8 is a control characteristics diagram for determining the operation mode when the air conditioner switch is ON. The numbers in parentheses in the diagram correspond to the above-mentioned operation modes. This also applies to the control characteristics diagrams of Figs. 9 and 10.

[0151] If it is determined in step S50 that the target air temperature TAO is lower than the cooling reference temperature α1, the process proceeds to step S60. If it is determined in step S50 that the target air temperature TAO is not lower than the cooling reference temperature α1, the process proceeds to step S90.

[0152] In step S60, it is determined whether or not cooling of the battery 70 is necessary. Specifically, in this embodiment, when the battery temperature TB detected by the battery temperature sensor 65 is equal to or higher than a predetermined reference cooling temperature KTB (35° C. in this embodiment), it is determined that cooling of the battery 70 is necessary. On the other hand, when the battery temperature TB is lower than the reference cooling temperature KTB, it is determined that cooling of the battery 70 is not necessary.

[0153] Of course, when the battery temperature TB is rising, it may be determined that cooling of the battery 70 is necessary when the battery temperature TB is equal to or higher than the reference cooling temperature KTB. Furthermore, when the battery temperature TB is falling, it may be determined that cooling of the battery 70 is not necessary when the battery temperature TB is equal to or lower than the low-temperature reference cooling temperature KTBL.

[0154] If it is determined in step S60 that cooling of the battery 70 is necessary, the process proceeds to step S70, where the (5) cooling air-conditioning mode is selected as the operation mode. If it is determined in step S60 that cooling of the battery 70 is not necessary, the process proceeds to step S80, where the (1) single air-conditioning mode is selected as the operation mode.

[0155] In step S90, it is determined whether the target air temperature TAO is lower than a dehumidification reference temperature β1. The dehumidification reference temperature β1 is a reference value for determining whether it is necessary to heat the blown air with a high heating capacity when performing dehumidification and heating of the vehicle interior.

[0156] The dehumidifying reference temperature β1 is determined based on the outside air temperature Tam by referring to a control map stored in advance in the control device 60. In the control map of this embodiment, as shown in Fig. 8, similar to the cooling reference temperature α1, the dehumidifying reference temperature β1 is determined to a lower value as the outside air temperature Tam decreases. Furthermore, for the same outside air temperature Tam, the dehumidifying reference temperature β1 is determined to a higher value than the cooling reference temperature α1.

[0157] If it is determined in step S90 that the target blow-out temperature TAO is lower than the dehumidification reference temperature β1, the process proceeds to step S100. If it is determined in step S90 that the target blow-out temperature TAO is not lower than the dehumidification reference temperature β1, the process proceeds to step S130.

[0158] In step S100, similar to step S60, it is determined whether or not cooling of battery 70 is necessary.

[0159] If it is determined in step S100 that cooling of the battery 70 is necessary, the process proceeds to step S110, where the (6) cooling series dehumidifying heating mode is selected as the operating mode. If it is determined in step S100 that cooling of the battery 70 is not necessary, the process proceeds to step S120, where the (2) series dehumidifying heating mode is selected as the operating mode.

[0160] In step S130, similar to step S60, it is determined whether or not cooling of the battery 70 is necessary. If it is determined in step S130 that cooling of the battery 70 is necessary, the process proceeds to step S140. If it is determined in step S130 that cooling of the battery 70 is not necessary, the process proceeds to step S170.

[0161] 4, in step S140, it is determined whether or not the heat of the outside air can be appropriately absorbed by the refrigerant in the outdoor heat exchanger 15. In step S140 of this embodiment, it is determined whether or not the heat of the outside air can be absorbed using the outdoor unit heat absorption possibility flag and the excessive outlet temperature flag.

[0162] The outdoor unit heat absorption possibility flag is determined using the outdoor unit temperature difference ΔTO, as shown in Fig. 11. The outdoor unit temperature difference ΔTO is a value (Tam - Tout) obtained by subtracting the outdoor unit temperature Tout, which corresponds to the refrigerant temperature in the outdoor heat exchanger 15, from the outside air temperature Tam.

[0163] In step S140, the target evaporator temperature TEO is used as the outdoor evaporator temperature Tout. The target evaporator temperature TEO is a target value for the refrigerant evaporation temperature in the indoor evaporator 18. In a refrigerant circuit in which the indoor evaporator 18 and the outdoor heat exchanger 15 are connected in parallel with respect to the refrigerant flow, as in the dehumidifying heating mode, the outdoor evaporator temperature Tout in the outdoor heat exchanger 15 also approaches the target evaporator temperature TEO.

[0164] 11 , when the outdoor unit temperature difference ΔTO is increasing, the outdoor unit heat absorption possibility flag is set to “Yes” when the outdoor unit temperature difference ΔTO becomes equal to or greater than the first reference temperature difference KΔTO1. When the outdoor unit heat absorption possibility flag is set to “Yes,” the refrigerant temperature in the outdoor heat exchanger 15 is sufficiently lower than the outside air temperature Tam, and the refrigerant in the outdoor heat exchanger 15 can absorb heat from the outside air.

[0165] Furthermore, when the outdoor unit temperature difference ΔTO is decreasing and the outdoor unit temperature difference ΔTO becomes equal to or smaller than the second reference temperature difference KΔTO2, the outdoor unit heat absorption possibility flag is set to "prohibited." When the outdoor unit heat absorption possibility flag is set to "prohibited," this means that the refrigerant temperature in the outdoor heat exchanger 15 is not sufficiently lower than the outside air temperature Tam, and the refrigerant in the outdoor heat exchanger 15 is not able to absorb heat from the outside air.

[0166] The excessive blow-out temperature flag is determined using the blow-out temperature difference ΔTAO, as shown in Fig. 12. The blow-out temperature difference ΔTAO is a value (TAO - TAOA) obtained by subtracting the estimated blow-out temperature TAOA from the target blow-out temperature TAO.

[0167] The estimated outlet temperature TAOA is determined by referring to a control map stored in the control device 60 based on the outside air temperature Tam and the intake air temperature Tin detected by the intake air temperature sensor 67. In the control map of this embodiment, the estimated outlet temperature TAOA is determined so that it increases with an increase in the outside air temperature Tam. Also, the estimated outlet temperature TAOA is determined so that it increases with an increase in the intake air temperature Tin.

[0168] 12, when the blowout temperature difference ΔTAO is increasing, if the blowout temperature difference ΔTAO becomes equal to or greater than the first reference blowout temperature difference KΔTAO1, the excessive blowout temperature flag is set to "normal." When the excessive blowout temperature flag is set to "normal," this means that the estimated blowout temperature TAOA is sufficiently lower than the target blowout temperature TAO, and the heat absorbed by the refrigerant from the outside air can be used to heat the blown air.

[0169] Furthermore, when the blowing temperature difference ΔTAO is decreasing, and the blowing temperature difference ΔTAO becomes equal to or less than the second reference blowing temperature difference KΔTAO2, the excessive blowing temperature flag is set to "excessive." When the excessive blowing temperature flag is set to "excessive," this means that the estimated blowing temperature TAOA is close to the target blowing temperature TAO, and the heating capacity of the blowing air would be excessive if the heat absorbed by the refrigerant from the outside air were used to heat the blowing air.

[0170] Therefore, in step S140 of this embodiment, when the outdoor unit heat absorption possibility flag is set to "possible" and the excessive discharge temperature flag is set to "normal," it is determined that the heat of the outdoor air can be appropriately absorbed by the refrigerant in the outdoor heat exchanger 15. In other words, it is determined that outdoor air heat absorption is possible.

[0171] If it is determined in step S140 that outside air heat absorption is possible, the process proceeds to step S150, where the (7-2) cooled outside air heat absorption HG dehumidifying heating mode is selected as the operation mode, as shown in Fig. 4. If it is determined in step S140 that outside air heat absorption is not possible, the process proceeds to step S160, where the (7-1) cooled outside air heat absorption HG dehumidifying heating mode is selected as the operation mode.

[0172] In step S170, it is determined whether or not heat can be absorbed from the outside air, as in step S140, as shown in Fig. 5. In step S170, the target evaporator temperature TEO is used as the outdoor unit temperature Tout.

[0173] If it is determined in step S170 that outside air heat absorption is possible, the process proceeds to step S180, where the (3-2) outside air heat absorption HG dehumidifying heating mode is selected as the operating mode. If it is determined in step S170 that outside air heat absorption is not possible, the process proceeds to step S190, where the (3-1) HG dehumidifying heating mode is selected as the operating mode.

[0174] Next, a case where the process proceeds from step S30 or step S40 to step S200 will be described. In step S200, as shown in Fig. 6, it is determined whether the target air temperature TAO is lower than a heating reference temperature γ. The heating reference temperature γ is a reference value for determining whether to heat the vehicle interior.

[0175] The heating reference temperature γ is determined based on the outside air temperature Tam by referring to a control map stored in advance in the control device 60. In the control map of this embodiment, as shown in Fig. 9 , the heating reference temperature γ is determined to a lower value as the outside air temperature Tam decreases. The heating reference temperature γ is set so that heating the blown air by the heater core 42 forming the heating section is effective for heating the space to be air-conditioned.

[0176] If it is determined in step S200 that the target outlet temperature TAO is lower than the heating reference temperature γ, it is not necessary to heat the blown air by the heater core 42, and the process proceeds to step S210. If it is determined in step S200 that the target outlet temperature TAO is not lower than the heating reference temperature γ, it is necessary to heat the blown air by the heater core 42, and the process proceeds to step S240.

[0177] In step S210, similar to step S60, it is determined whether or not cooling of battery 70 is necessary.

[0178] If it is determined in step S210 that cooling of the battery 70 is necessary, the process proceeds to step S220, where the (11) cooling mode is selected as the operating mode. If it is determined in step S210 that cooling of the battery 70 is not necessary, the process proceeds to step S230, where the (12) fan mode is selected as the operating mode.

[0179] In step S240, it is determined whether the target outlet temperature TAO is lower than a hot gas reference temperature δ. The hot gas reference temperature δ is a reference value for determining whether it is necessary to heat the blown air with a high heating capacity when heating the vehicle interior.

[0180] The hot gas reference temperature δ is determined based on the outside air temperature Tam by referring to a control map stored in advance in the control device 60. In the control map of this embodiment, as shown in Fig. 9, similar to the heating reference temperature γ, the hot gas reference temperature δ is determined to decrease as the outside air temperature Tam decreases. Furthermore, the hot gas reference temperature δ is determined to be a value higher than the heating reference temperature γ.

[0181] If it is determined in step S240 that the target blow-out temperature TAO is lower than the hot gas reference temperature δ, the process proceeds to step S250. If it is determined in step S240 that the target blow-out temperature TAO is not lower than the hot gas reference temperature δ, the process proceeds to step S270.

[0182] In step S250, similar to step S60, it is determined whether or not cooling of battery 70 is necessary.

[0183] If it is determined in step S250 that cooling of the battery 70 is necessary, the process proceeds to step S300. If it is determined in step S250 that cooling of the battery 70 is not necessary, the process proceeds to step S260, where the (4-1) outside air heat absorption heating mode is selected as the operation mode.

[0184] In step S270, similar to step S60, it is determined whether or not cooling of battery 70 is necessary.

[0185] If it is determined in step S270 that cooling of the battery 70 is necessary, the process proceeds to step S300. If it is determined in step S270 that cooling of the battery 70 is not necessary, the process proceeds to step S280, in which the (4-2) HG heating mode is selected as the operation mode.

[0186] If it is determined in steps S250 and S270 that cooling of the battery 70 is necessary and the process proceeds to step S300, it is necessary to both heat the vehicle interior and cool the battery 70. Therefore, in the heat pump cycle 10, it is necessary to appropriately adjust the amount of heat released by the refrigerant to the high-temperature side heat medium in the water-refrigerant heat exchanger 13 and the amount of heat absorbed by the refrigerant from the low-temperature side heat medium in the chiller 20.

[0187] Therefore, in step S300, it is determined whether the target blown air temperature TAO is lower than the first cooling / heating reference temperature α2, as shown in Fig. 7. The first cooling / heating reference temperature α2 is a reference value for determining whether it is necessary to heat the blown air with a high heating capacity when heating the vehicle cabin.

[0188] The first cooling / heating reference temperature α2 is determined based on the outside air temperature Tam by referring to a control map stored in advance in the control device 60. In the control map of this embodiment, as shown in Fig. 10, the first cooling / heating reference temperature α2 is determined to a lower value as the outside air temperature Tam decreases. Here, for the same outside air temperature Tam, the first cooling / heating reference temperature α2 is determined to a higher value than the cooling reference temperature α1.

[0189] If it is determined in step S300 that the target air temperature TAO is lower than the first cooling / heating reference temperature α2, the process proceeds to step S310, where the (8) cooling device heat absorption heating mode is selected. If it is determined in step S300 that the target air temperature TAO is not lower than the first cooling / heating reference temperature α2, the process proceeds to step S320.

[0190] In step S320, it is determined whether the target air temperature TAO is lower than a second reference temperature β2 for cooling and heating, which is a reference value for determining whether the air needs to be heated with a higher heating capacity when heating the passenger compartment.

[0191] The second cooling / heating reference temperature β2 is determined based on the outside air temperature Tam by referring to a control map previously stored in the control device 60. In the control map of this embodiment, as shown in Fig. 10, similar to the first cooling / heating reference temperature α2, the second cooling / heating reference temperature β2 is determined to a lower value as the outside air temperature Tam decreases. Furthermore, for the same outside air temperature Tam, the second cooling / heating reference temperature β2 is determined to a higher value than the dehumidification reference temperature β1.

[0192] If it is determined in step S320 that the target air temperature TAO is lower than the second cooling / heating reference temperature β2, the process proceeds to step S330, where the (9) cooled outside air heat absorption heating mode is selected. If it is determined in step S320 that the target air temperature TAO is not lower than the second cooling / heating reference temperature β2, the process proceeds to step S340.

[0193] In step S340, it is determined whether heat absorption by the outside air is possible. In step S340, the saturation temperature of the refrigerant in the target low-pressure PSO is used as the outdoor unit temperature Tout. The target low-pressure PSO is a target value for the temperature of the refrigerant drawn into the compressor 11. In the refrigerant circuit in the heating mode, the outdoor unit temperature Tout in the outdoor heat exchanger 15 also approaches the saturation temperature of the refrigerant in the target low-pressure PSO. The rest of the determination is the same as in step S140.

[0194] If it is determined in step S340 that outside air heat absorption is possible, the process proceeds to step S350, where the (10-2) cooled outside air heat absorption HG heating mode is selected as the operating mode. If it is determined in step S340 that outside air heat absorption is not possible, the process proceeds to step S360, where the (10-1) cooled outside air heat absorption HG heating mode is selected as the operating mode.

[0195] The control program of this embodiment switches between the operating modes as described above. The control program then repeats the control routines of reading the detection signals and operation signals, calculating the target air temperature TAO, selecting the operating mode, and controlling the various controlled devices according to the operating mode at each predetermined control cycle until a predetermined termination condition for the control program is met. The detailed operation of each operating mode is described below.

[0196] (1) Single Cooling Mode In the single cooling mode, the control device 60 executes a control flow for the single cooling mode. In the control flow for the single cooling mode, the control device 60 determines a target evaporator temperature TEO. The target evaporator temperature TEO is a target value for the refrigerant evaporation temperature in the interior evaporator 18. Therefore, the control flow for the single cooling mode includes a target evaporator temperature determination unit that determines the target evaporator temperature TEO.

[0197] The target evaporator temperature determination unit determines the target evaporator temperature TEO based on the target outlet temperature TAO by referring to a control map stored in advance in the control device 60. The control map for the single cooling mode determines the target evaporator temperature TEO so that it increases as the target outlet temperature TAO increases. The target evaporator temperature TEO is determined to a temperature (1° C. or higher in this embodiment) that will not cause frost to form on the interior evaporator 18.

[0198] Furthermore, the control device 60 determines an increase / decrease amount ΔIVO of the rotation speed of the compressor 11. The increase / decrease amount ΔIVO in the single cooling mode is determined by a feedback control method based on, for example, the deviation between the target evaporator temperature TEO and the evaporator temperature Tefin detected by the evaporator temperature sensor 62f so that the evaporator temperature Tefin approaches the target evaporator temperature TEO.

[0199] The control device 60 also determines a target degree of subcooling SCO2 of the refrigerant flowing out from the outdoor heat exchanger 15. The target degree of subcooling SCO2 is determined based on the outside air temperature Tam and by referring to a control map pre-stored in the control device 60. In the control map for the single cooling mode, the target degree of subcooling SCO2 is determined so that the coefficient of performance (COP) of the cycle approaches a local maximum value.

[0200] Furthermore, the control device 60 determines an increase or decrease ΔEVC in the throttle opening of the cooling expansion valve 14b. The increase or decrease ΔEVC in the single cooling mode is determined by a feedback control method based on the deviation between the target subcooling degree SCO2 and the subcooling degree SC2 of the refrigerant on the outlet side of the outdoor heat exchanger 15, so that the subcooling degree SC2 of the refrigerant on the outlet side of the outdoor heat exchanger 15 approaches the target subcooling degree SCO2.

[0201] The degree of subcooling SC2 of the refrigerant on the outlet side of the outdoor heat exchanger 15 is calculated using the outdoor unit side refrigerant temperature T2 and the outdoor unit side refrigerant pressure P2 detected by the outdoor unit side refrigerant temperature and pressure sensor 62c.

[0202] The control device 60 also calculates the opening degree SW of the air mix door 34. Specifically, the opening degree SW is calculated using the following formula F2: SW={TAO+(Te+C2)} / {TWH+(Te+C2)}×100(%) (F2), where Te is the evaporator-side refrigerant temperature detected by the evaporator-side refrigerant temperature / pressure sensor 62d. TWH is the high-temperature side heat medium temperature detected by the high-temperature side heat medium temperature sensor 63a. C2 is a control constant.

[0203] Furthermore, the control device 60 determines a control signal to be output to an actuator for driving the air mix door 34 in accordance with the opening degree SW.

[0204] For example, when the opening degree SW is 100%, the control signal is determined so that the air mix door 34 is displaced to a so-called max hot position, which fully opens the air passage on the heater core 42 side and fully closes the cool air bypass passage 35. When the opening degree SW is 0%, the control signal is determined so that the air mix door 34 is displaced to a so-called max cool position, which fully closes the air passage on the heater core 42 side and fully opens the cool air bypass passage 35.

[0205] The control device 60 determines the control signals to be output to the heating expansion valve 14 a in a fully open state, the cooling expansion valve 14 b in a throttled state that exerts a refrigerant decompression effect, the cooling expansion valve 14 c in a fully closed state, and the bypass side flow control valve 14 d in a fully closed state. The control device 60 also determines the control voltages to be output to the high-pressure side opening / closing valve 22 a and the low-pressure side opening / closing valve 22 b.

[0206] Furthermore, the control device 60 appropriately determines the operating states of other control target devices. For example, the control device 60 determines the control voltage to be output to the high-temperature side pump 41 so as to exhibit a predetermined reference pumping capacity, and stops the low-temperature side pump 51.

[0207] For example, the control device 60 determines the control voltage to be output to the indoor blower 32 based on the target blowing temperature TAO by referring to a control map stored in advance in the control device 60. In the control map of this embodiment, the control voltage is determined so that the airflow rate of the indoor blower 32 is maximized in the extremely low temperature range (maximum cooling range) and the extremely high temperature range (maximum heating range) of the target blowing temperature TAO, and the airflow rate decreases as the temperature approaches the intermediate temperature range.

[0208] The control device 60 outputs control signals or control voltages to the various control target devices so that the control states of the various control target devices determined as described above are obtained. Then, as indicated by Z in FIG. 3, the control flow returns to step S10.

[0209] Therefore, in the heat pump cycle 10 in the cooling-only mode, the refrigerant discharged from the compressor 11 is switched to a refrigerant circuit in which it circulates in the following order: the water-refrigerant heat exchanger 13, the fully open heating expansion valve 14a, the outdoor heat exchanger 15, the cooling expansion valve 14b, the indoor evaporator 18, the accumulator 23, and the intake port of the compressor 11.

[0210] Therefore, in the heat pump cycle 10 in the cooling-only mode, the water-refrigerant heat exchanger 13 and the outdoor heat exchanger 15 function as condensers that condense the refrigerant by dissipating heat, and the indoor evaporator 18 functions as an evaporator that evaporates the refrigerant, forming a vapor compression refrigeration cycle.

[0211] In the water-refrigerant heat exchanger 13, the refrigerant dissipates heat to the high-temperature side heat medium, thereby heating the high-temperature side heat medium. In the indoor evaporator 18, the refrigerant absorbs heat from the blown air, thereby cooling the blown air.

[0212] In the high-temperature side heat medium circuit 40 in the sole cooling mode, the high-temperature side heat medium pumped from the high-temperature side pump 41 circulates sequentially through the heat medium passage of the water-refrigerant heat exchanger 13, the heater core 42, and the suction port of the high-temperature side pump 41. As a result, the high-temperature side heat medium heated in the water-refrigerant heat exchanger 13 flows into the heater core 42.

[0213] In the interior air conditioning unit 30 in the sole cooling mode, the air blown from the interior blower 32 is cooled by the interior evaporator 18. The air cooled by the interior evaporator 18 is heated by the heater core 42 depending on the opening degree of the air mix door 34. The conditioned air, whose temperature has been adjusted to approach the target outlet temperature TAO, is then blown into the vehicle compartment. This achieves cooling of the vehicle compartment.

[0214] (2) Series Dehumidifying Heating Mode In the series dehumidifying heating mode, the control device 60 executes a control flow for the series dehumidifying heating mode. In the control flow for the series dehumidifying heating mode, the control device 60 determines the target evaporator temperature TEO, similar to the sole cooling mode. Therefore, the control flow for the series dehumidifying heating mode includes a target evaporator temperature determination unit. Furthermore, similar to the sole cooling mode, the control device 60 determines the increase / decrease amount ΔIVO of the rotation speed of the compressor 11.

[0215] Furthermore, the control device 60 determines the target high-temperature-side heat medium temperature TWHO so that the blown air can be sufficiently heated by the heater core 42. This is the target value of the high-temperature-side heat medium temperature TWH detected by the high-temperature-side heat medium temperature sensor 63a.

[0216] The target high-temperature-side heat medium temperature TWHO is determined by referring to a control map stored in advance in the control device 60, based on the target blowing temperature TAO and the efficiency of the heater core 42. In the control map for the serial dehumidifying heating mode, the target high-temperature-side heat medium temperature TWHO is determined so as to increase as the target blowing temperature TAO increases.

[0217] Furthermore, the control device 60 determines the amount of change ΔKPN1 in the opening degree pattern KPN1 based on the target blow-out temperature TAO and the target high-temperature-side heat medium temperature TWHO by referring to a control map stored in advance in the control device 60.

[0218] The opening pattern KPN1 is a parameter for determining a combination of the throttle opening of the heating expansion valve 14 a and the throttle opening of the cooling expansion valve 14 b. The opening pattern KPN1 corresponds to the ratio of the throttle opening of the cooling expansion valve 14 b to the throttle opening of the heating expansion valve 14 a.

[0219] In the control map for the serial dehumidifying and heating mode, the opening pattern KPN1 is increased as the target blowing temperature TAO increases. That is, as the target blowing temperature TAO increases, the ratio of the opening of the cooling expansion valve 14b to the opening of the heating expansion valve 14a is increased.

[0220] Furthermore, the control device 60 calculates the opening degree SW of the air mix door 34 in the same manner as in the single cooling mode.

[0221] The control device 60 determines the control signals to be output to the heating expansion valve 14 a, the cooling expansion valve 14 b, the cooling expansion valve 14 c, and the bypass-side flow control valve 14 d so that the valves are throttled, fully closed, and fully closed, respectively. The control device 60 also determines the control voltages to be output to the high-pressure side on-off valve 22 a, and the low-pressure side on-off valve 22 b so that the valves are closed.

[0222] Furthermore, the control device 60 appropriately determines the operating states of other control target devices, similarly to the single cooling mode.

[0223] The control device 60 outputs control signals or control voltages to the various control target devices so that the control states of the various control target devices determined as described above are obtained. Then, as indicated by Z in FIG. 3, the control flow returns to step S10.

[0224] Therefore, in the heat pump cycle 10 in the serial dehumidifying and heating mode, the refrigerant discharged from the compressor 11 is switched to a refrigerant circuit in which it circulates in the following order: the water-refrigerant heat exchanger 13, the heating expansion valve 14a, the outdoor heat exchanger 15, the cooling expansion valve 14b, the indoor evaporator 18, the accumulator 23, and the intake port of the compressor 11.

[0225] Therefore, in the heat pump cycle 10 in the serial dehumidifying heating mode, a vapor compression refrigeration cycle is configured in which the water-refrigerant heat exchanger 13 functions as a condenser and the indoor evaporator 18 functions as an evaporator.

[0226] Furthermore, in the heat pump cycle 10 in the serial dehumidifying heating mode, when the saturation temperature of the refrigerant in the outdoor heat exchanger 15 is higher than the outdoor air temperature Tam, the outdoor heat exchanger 15 functions as a condenser. When the saturation temperature of the refrigerant in the outdoor heat exchanger 15 is lower than the outdoor air temperature Tam, the outdoor heat exchanger 15 functions as an evaporator.

[0227] In the water-refrigerant heat exchanger 13, the refrigerant dissipates heat to the high-temperature side heat medium, thereby heating the high-temperature side heat medium. In the indoor evaporator 18, the refrigerant absorbs heat from the blown air, thereby cooling the blown air.

[0228] In the high-temperature side heat medium circuit 40 in the series dehumidifying and heating mode, the high-temperature side heat medium heated in the water-refrigerant heat exchanger 13 flows into the heater core 42, as in the single cooling mode.

[0229] In the interior air conditioning unit 30 in the serial dehumidifying and heating mode, the air blown from the interior blower 32 is cooled and dehumidified by the interior evaporator 18. The air cooled and dehumidified by the interior evaporator 18 is reheated by the heater core 42 depending on the opening degree of the air mix door 34. The conditioned air, whose temperature has been adjusted to approach the target outlet temperature TAO, is then blown into the vehicle cabin. This achieves dehumidifying and heating the vehicle cabin.

[0230] (3-1) HG Dehumidifying and Heating Mode In the HG dehumidifying and heating mode, the control device 60 executes the control flow for the HG dehumidifying and heating mode shown in FIG.

[0231] First, in step S1901, a target high-temperature-side heat medium temperature TWHO of the high-temperature-side heat medium is determined. The target high-temperature-side heat medium temperature TWHO is determined by referring to a control map based on the vehicle interior set temperature Tset set by the temperature setting switch. The control map for the HG dehumidifying and heating mode determines the target high-temperature-side heat medium temperature TWHO to increase as the outside air temperature Tam decreases within a predetermined range of the vehicle interior set temperature Tset.

[0232] In step S1902, an increase / decrease ΔIVO in the rotation speed of the compressor 11 is determined. The increase / decrease ΔIVO in the HG dehumidifying heating mode is determined by a feedback control method based on the deviation between the target high-temperature-side heat medium temperature TWHO and the high-temperature-side heat medium temperature TWH, etc., so that the high-temperature-side heat medium temperature TWH approaches the target high-temperature-side heat medium temperature TWHO.

[0233] In step S1903, a target degree of superheat SHEO of the refrigerant on the outlet side of the interior evaporator 18 is determined. A predetermined constant (5° C. in this embodiment) can be used as the target degree of superheat SHEO.

[0234] In step S1904, the increase / decrease amount ΔEVC of the throttle opening of the cooling expansion valve 14b is determined. The increase / decrease amount ΔEVC in the HG dehumidifying / heating mode is determined by a feedback control method based on the deviation between the target superheat degree SHEO and the superheat degree SHE of the refrigerant on the outlet side of the indoor evaporator 18, so that the superheat degree SHE of the refrigerant on the outlet side of the indoor evaporator 18 approaches the target superheat degree SHEO.

[0235] The degree of superheat SHE of the refrigerant on the outlet side of the interior evaporator 18 is calculated using the evaporator side refrigerant temperature Te and the evaporator side refrigerant pressure Pe detected by the evaporator side refrigerant temperature / pressure sensor 62d.

[0236] In step S1905, a target degree of subcooling SCO1 of the refrigerant flowing out of the water-refrigerant heat exchanger 13 is determined. The target degree of subcooling SCO1 is determined based on the outside air temperature Tam and by referring to a control map previously stored in the control device 60. The target degree of subcooling SCO1 may be a constant value.

[0237] In step S1906, the controller 10 determines an increase or decrease ΔEVB in the throttle opening of the cooling expansion valve 14c. The increase or decrease ΔEVB in the HG dehumidifying and heating mode is determined based on the deviation between the target subcooling degree SCO1 and the subcooling degree SC1 of the refrigerant flowing out of the water-refrigerant heat exchanger 13, using a feedback control method, so that the subcooling degree SC1 of the refrigerant flowing out of the water-refrigerant heat exchanger 13 approaches the target subcooling degree SCO1.

[0238] The degree of subcooling SC1 of the refrigerant flowing out from the water-refrigerant heat exchanger 13 is calculated using the high-pressure side refrigerant temperature T1 and the high-pressure side refrigerant pressure P1 detected by the high-pressure side refrigerant temperature and pressure sensor 62b.

[0239] In step S1907, a target low-pressure PSO is determined, which is a target value of the intake refrigerant drawn into the compressor 11. In the HG dehumidifying and heating mode, the target low-pressure PSO is determined so that the refrigerant evaporation temperature in the indoor evaporator 18 is a temperature at which the blown air can be dehumidified without causing frosting on the indoor evaporator 18. Therefore, the saturation temperature of the refrigerant at the target low-pressure PSO corresponds to the target evaporator temperature TEO. Therefore, in the HG dehumidifying and heating mode, step S1907 serves as a target evaporator temperature determination unit.

[0240] In step S1908, the increase / decrease amount ΔEVHG of the opening of the bypass-side flow control valve 14d is determined. The increase / decrease amount ΔEVHG in the HG dehumidifying / heating mode is determined by a feedback control method based on factors such as the deviation between the target low-pressure PSO and the chiller-side refrigerant pressure Pc detected by the chiller-side refrigerant temperature / pressure sensor 62e so that the chiller-side refrigerant pressure Pc approaches the target low-pressure PSO.

[0241] In step S1909, the opening degree SW of the air mix door 34 is calculated, similarly to the single cooling mode.

[0242] In step S1910, the control signals to be output to the heating expansion valve 14a are determined so that the heating expansion valve 14a is fully closed, the cooling expansion valve 14b is determined so that the cooling expansion valve 14c is determined so that the cooling expansion valve 14d is determined so that the bypass side flow control valve 14d is determined so that the bypass side flow control valve 14d is also determined so that the high pressure side opening / closing valve 22a is opened and the low pressure side opening / closing valve 22b is closed.

[0243] Furthermore, the control device 60 appropriately determines the operating states of other control target devices, similarly to the single cooling mode.

[0244] In step S1911, a control signal or a control voltage is output to each of the control target devices so that the control states of the various control target devices determined as described above are obtained. Then, as indicated by Z in Figures 3 and 13, the control flow returns to step S10.

[0245] 14 , in the heat pump cycle 10 in the HG dehumidifying and heating mode, the refrigerant discharged from the compressor 11 circulates in the following order: the first three-way joint 12a, the water-refrigerant heat exchanger 13, the high-pressure side passage 21a, the fifth three-way joint 12e, the cooling expansion valve 14b, the indoor evaporator 18, the sixth three-way joint 12f, the seventh three-way joint 12g, the accumulator 23, and the suction port of the compressor 11. Furthermore, the refrigerant discharged from the compressor 11 circulates in the following order: the first three-way joint 12a, the water-refrigerant heat exchanger 13, the high-pressure side passage 21a, the fifth three-way joint 12e, the cooling expansion valve 14c, the chiller 20, the sixth three-way joint 12f, the seventh three-way joint 12g, 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 in which it circulates in the following order: the first three-way joint 12a, the bypass-side flow control valve 14d arranged in the bypass passage 21c, the seventh three-way joint 12g, the accumulator 23, and the intake port of the compressor 11.

[0246] Therefore, in the heat pump cycle 10 in the HG dehumidifying and heating mode, the state of the refrigerant changes as shown in the Mollier diagram of FIG.

[0247] The flow of refrigerant discharged from the compressor 11 (point a15 in FIG. 15 ) is branched at the first three-way joint 12a. One of the refrigerant branches at the first three-way joint 12a flows into the water-refrigerant heat exchanger 13 and dissipates heat to the high-temperature side heat medium (from point a15 to point b15 in FIG. 15 ). This heats the high-temperature side heat medium.

[0248] The refrigerant flowing out of the water-refrigerant heat exchanger 13 flows into the high-pressure side passage 21a. The refrigerant flowing out of the high-pressure side passage 21a is branched at the fifth three-way joint 12e. One of the branches of the refrigerant flowing out of the fifth three-way joint 12e flows into the cooling expansion valve 14b and is decompressed (from point b15 to point e15 in FIG. 15 ).

[0249] The refrigerant decompressed by the cooling expansion valve 14b flows into the interior evaporator 18. The refrigerant that flows into the interior evaporator 18 absorbs heat from the air blown by the interior blower 32 and evaporates (from point e15 to point f15 in FIG. 15 ). This cools and dehumidifies the air. The refrigerant that flows out of the interior evaporator 18 flows through the third check valve 16c into one inlet of the sixth three-way joint 12f.

[0250] The other refrigerant branched at the fifth three-way joint 12e flows into the cooling expansion valve 14c and is decompressed (from point b15 to point g15 in FIG. 15). The refrigerant decompressed at the cooling expansion valve 14c flows into the chiller 20. In the HG dehumidifying heating mode, the low-temperature side pump 51 is stopped, so there is no heat exchange between the refrigerant and the low-temperature side heat medium in the chiller 20. The refrigerant flowing out of the chiller 20 flows into the other inlet of the sixth three-way joint 12f.

[0251] At the sixth three-way joint 12f, the refrigerant flowing out from the indoor evaporator 18 and the refrigerant flowing out from the chiller 20 join together and are mixed. The refrigerant flowing out from the sixth three-way joint 12f flows into the other inlet of the seventh three-way joint 12g.

[0252] The other refrigerant branched at the first three-way joint 12a flows into a bypass passage 21c. The refrigerant flowing into the bypass passage 21c is flow-regulated and decompressed by the bypass-side flow control valve 14d (from point a15 to point i15 in FIG. 15). The refrigerant decompressed by the bypass-side flow control valve 14d flows into one inlet of the seventh three-way joint 12g.

[0253] At the seventh three-way joint 12g, the refrigerant flowing out from the sixth three-way joint 12f and the refrigerant flowing out from the bypass passage 21c join together and are mixed. The refrigerant flowing out from the seventh three-way joint 12g flows into the accumulator 23 via the eighth three-way joint 12h. The refrigerant flowing into the accumulator 23 is mixed more homogeneously (point j15 in FIG. 15 ). The refrigerant flowing out from the accumulator 23 is drawn into the compressor 11 and compressed again.

[0254] In addition, in the high-temperature side heat medium circuit 40 in the HG dehumidifying and heating mode, as shown by the solid arrow in Figure 14, the high-temperature side heat medium heated in the water-refrigerant heat exchanger 13 flows into the heater core 42, as in the single cooling mode.

[0255] In the interior air conditioning unit 30 in the HG dehumidifying and heating mode, the temperature of the air is adjusted to approach the target outlet temperature TAO and the air is blown into the vehicle compartment, as in the series dehumidifying and heating mode. This achieves dehumidifying and heating the vehicle compartment.

[0256] In the HG dehumidifying and heating mode, the refrigerant having a relatively high enthalpy is merged with the refrigerant flowing out from the chiller 20 via the bypass passage 21c.

[0257] According to this, when the refrigerant discharge capacity of the compressor 11 is increased, the heating capacity of the high-temperature side heat medium in the water-refrigerant heat exchanger 13 can be improved without reducing the refrigerant evaporation pressure in the indoor evaporation section 18. In other words, when the refrigerant discharge capacity of the compressor 11 is increased, the heating capacity of the high-temperature side heat medium in the water-refrigerant heat exchanger 13 can be improved without causing frost formation in the indoor evaporation section 18.

[0258] Therefore, in the HG dehumidifying and heating mode, the heating capacity of the heater for the blown air can be improved more than in the serial dehumidifying and heating mode.

[0259] (3-2) Outdoor Air Heat Absorption HG Dehumidifying and Heating Mode In the outdoor air heat absorption HG dehumidifying and heating mode, the controller 60 executes the control flow for the outdoor air heat absorption HG dehumidifying and heating mode shown in FIG.

[0260] In steps S1801 to S1808 in Fig. 16, the control states of various control target devices are determined, similar to steps S1901 to S1908 in the HG dehumidifying and heating mode in Fig. 13. Therefore, in the outside air heat absorption HG dehumidifying and heating mode, step S1807 is the target evaporator temperature determination section.

[0261] In step S1809, a target degree of superheat SHO2 of the refrigerant on the outlet side of the outdoor heat exchanger 15 is determined. As with the target degree of superheat SHEO of the refrigerant on the outlet side of the indoor evaporator 18, a predetermined constant (5° C. in this embodiment) can be used as the target degree of superheat SHO2.

[0262] In step S1810, the increase / decrease amount ΔEVH of the throttle opening of the heating expansion valve 14a is determined. The increase / decrease amount ΔEVH in the outdoor air heat absorption HG dehumidifying heating mode is determined by a feedback control method based on the deviation between the target superheat degree SHO2 and the superheat degree SH2 of the refrigerant on the outlet side of the outdoor heat exchanger 15, etc., so that the superheat degree SH2 of the refrigerant on the outlet side of the outdoor heat exchanger 15 approaches the target superheat degree SHO2.

[0263] The degree of superheat SH2 of the refrigerant on the outlet side of the outdoor heat exchanger 15 is calculated using the outdoor unit side refrigerant temperature T2 and the outdoor unit side refrigerant pressure P2 detected by the outdoor unit side refrigerant temperature / pressure sensor 62c.

[0264] In step S1811, the opening degree SW of the air mix door 34 is calculated, similarly to the single cooling mode.

[0265] In step S1812, the control signals to be output to the heating expansion valve 14a, the cooling expansion valve 14b, the cooling expansion valve 14c, and the bypass side flow control valve 14d are determined so as to place them in a throttled state, a throttled state, a throttled state, and a throttled state, respectively. Also, the control voltages to be output to the high-pressure side opening / closing valve 22a and the low-pressure side opening / closing valve 22b are determined so as to open them, respectively.

[0266] Furthermore, the control device 60 appropriately determines the operating states of other control target devices, similarly to the single cooling mode.

[0267] In step S1813, a control signal or a control voltage is output to each of the control target devices so that the control states of the various control target devices determined as described above are obtained. Then, as indicated by Z in Figures 3 and 16, the control flow returns to step S10.

[0268] Therefore, in the heat pump cycle 10 in the outdoor air heat absorption HG dehumidifying heating mode, the refrigerant discharged from the compressor 11 flows in the same manner as in the HG dehumidifying heating mode, as shown by the solid arrows in Fig. 17. Furthermore, the refrigerant discharged from the compressor 11 is switched to a refrigerant circuit in which it circulates through the first three-way joint 12a, the water-refrigerant heat exchanger 13, the second three-way joint 12b, the heating expansion valve 14a, the outdoor heat exchanger 15, the low-pressure side passage 21b, the eighth three-way joint 12h, the accumulator 23, and the suction port of the compressor 11, in this order.

[0269] That is, the refrigerant flow is switched to a refrigerant circuit in which the indoor evaporator 18 and the outdoor heat exchanger 15 are connected in parallel with respect to the flow of refrigerant flowing out of the water-refrigerant heat exchanger 13. Therefore, in the heat pump cycle 10 in the HG dehumidifying heating mode, the state of the refrigerant changes as shown in the Mollier diagram of FIG.

[0270] In Figure 18, the refrigerant states at points equivalent in cycle configuration to those in the Mollier diagram of Figure 15 described in the HG dehumidifying and heating mode are indicated by the same reference characters (alphabet) as in Figure 15, with only the subscripts (numbers) changed to match the diagram numbers. This also applies to the following Mollier diagrams.

[0271] In the outdoor air heat absorption HG dehumidifying heating mode, the refrigerant flowing out of the water-refrigerant heat exchanger 13 is branched at the second three-way joint 12b, unlike in the HG dehumidifying heating mode. One of the refrigerants flowing out from one outlet of the second three-way joint 12b flows into the heating expansion valve 14a and is decompressed (from point b18 to point c18 in FIG. 18 ).

[0272] The refrigerant decompressed by the heating expansion valve 14a flows into the outdoor heat exchanger 15. The refrigerant that has flowed into the outdoor heat exchanger 15 absorbs heat from the outside air and evaporates (from point c18 to point d18 in FIG. 18 ). The refrigerant that has flowed out of the outdoor heat exchanger 15 flows through the low-pressure side passage 21b into one inlet of the eighth three-way joint 12h.

[0273] In this embodiment, the target degree of superheat SHEO of the refrigerant on the outlet side of the indoor evaporator 18 and the target degree of superheat SHO2 of the refrigerant on the outlet side of the outdoor heat exchanger 15 are set to the same value. Therefore, the state of the refrigerant flowing out of the outdoor heat exchanger 15 (point d18 in FIG. 18) and the state of the refrigerant flowing out of the indoor evaporator 18 (point f18 in FIG. 18) are substantially the same.

[0274] At the eighth three-way joint 12h, the refrigerant flowing out from the outdoor heat exchanger 15 and the refrigerant flowing out from the seventh three-way joint 12g join together and are mixed. The refrigerant flowing out from the eighth three-way joint 12h flows into the accumulator 23. The refrigerant flowing into the accumulator 23 is mixed more homogeneously (point j18 in Figure 18). The refrigerant flowing out from the accumulator 23 is drawn into the compressor 11 and compressed again. Other operations are the same as those in the HG dehumidifying and heating mode.

[0275] In addition, in the high-temperature side heat medium circuit 40 in the outdoor air heat absorption HG dehumidifying heating mode, as shown by the solid arrow in Figure 17, the high-temperature side heat medium heated in the water-refrigerant heat exchanger 13 flows into the heater core 42, just like in the single cooling mode.

[0276] In the interior air conditioning unit 30 in the outside air heat absorption HG dehumidifying and heating mode, the conditioned air whose temperature has been adjusted to approach the target outlet temperature TAO is blown into the vehicle cabin, as in the series dehumidifying and heating mode, thereby realizing dehumidifying and heating the vehicle cabin.

[0277] In the outdoor air heat absorption HG dehumidifying heating mode, as in the HG dehumidifying heating mode, the heating capacity of the blown air in the heating section can be improved compared to the serial dehumidifying heating mode. Furthermore, in the outdoor air heat absorption HG dehumidifying heating mode, the blown air can be heated using heat absorbed from the outdoor air by the refrigerant in the outdoor heat exchanger 15. Therefore, in the outdoor air heat absorption HG dehumidifying heating mode, the operating efficiency of the heat pump cycle 10 can be improved compared to the HG dehumidifying heating mode.

[0278] (4-1) Outdoor Air Heating Mode In the outdoor air heat absorption heating mode, the control device 60 executes the control flow for the outdoor air heat absorption heating mode. In the control flow for the outdoor air heat absorption heating mode, the control device 60 determines the target high-temperature side heat medium temperature TWHO of the high-temperature side heat medium, as in the HG dehumidifying heating mode. Furthermore, the control device 60 determines the increase / decrease amount ΔIVO of the rotation speed of the compressor 11, as in the HG dehumidifying heating mode.

[0279] The control device 60 also determines a target degree of subcooling SCO1 for the refrigerant flowing out of the water-refrigerant heat exchanger 13. The target degree of subcooling SCO1 for the outdoor air endoscopy heating mode is determined based on at least one of the intake air temperature Tin and the outdoor air temperature Tam, with reference to a control map pre-stored in the control device 60. In the control map for the outdoor air endoscopy heating mode, the target degree of subcooling SCO1 is determined so that the coefficient of performance (COP) of the cycle approaches a local maximum value.

[0280] Furthermore, the control device 60 determines an increase / decrease amount ΔEVH of the throttle opening of the heating expansion valve 14a. The increase / decrease amount ΔEVH in the outside air heat absorption heating mode is determined by a feedback control method based on factors such as the deviation between the target subcooling degree SCO1 and the subcooling degree SC1 of the refrigerant flowing out of the water-refrigerant heat exchanger 13 so that the subcooling degree SC1 of the refrigerant flowing out of the water-refrigerant heat exchanger 13 approaches the target subcooling degree SCO1.

[0281] Furthermore, the control device 60 calculates the opening degree SW of the air mix door 34 in the same manner as in the single cooling mode.

[0282] The control device 60 determines the control signals to be output to the heating expansion valve 14 a, the cooling expansion valve 14 b, the cooling expansion valve 14 c, and the bypass-side flow control valve 14 d so that the heating expansion valve 14 a is throttled, the cooling expansion valve 14 b is fully closed, the cooling expansion valve 14 c is fully closed, and the bypass-side flow control valve 14 d is fully closed. The control device 60 also determines the control voltages to be output to the high-pressure side opening / closing valve 22 a and the low-pressure side opening / closing valve 22 b so that the high-pressure side opening / closing valve 22 a is closed and the low-pressure side opening / closing valve 22 b is opened.

[0283] Furthermore, the control device 60 appropriately determines the operating states of other control target devices, similarly to the single cooling mode.

[0284] The control device 60 outputs control signals or control voltages to the various control target devices so that the control states of the various control target devices determined as described above are obtained. Then, as indicated by Z in FIG. 3, the control flow returns to step S10.

[0285] Therefore, in the heat pump cycle 10 in the outdoor air heat absorption heating mode, the refrigerant discharged from the compressor 11 is switched to a refrigerant circuit in which it circulates in the following order: the water-refrigerant heat exchanger 13, the heating expansion valve 14a, the outdoor heat exchanger 15, the low-pressure side passage 21b, the accumulator 23, and the intake port of the compressor 11.

[0286] Therefore, in the heat pump cycle 10 in the outdoor air heat absorption heating mode, the water-refrigerant heat exchanger 13 functions as a condenser, and the outdoor heat exchanger 15 functions as an evaporator, forming a vapor compression refrigeration cycle. In the water-refrigerant heat exchanger 13, the refrigerant dissipates heat to the high-temperature side heat medium, thereby heating the high-temperature side heat medium. In the outdoor heat exchanger 15, the refrigerant absorbs heat from the outdoor air and evaporates.

[0287] In the high-temperature side heat medium circuit 40 in the outdoor air heat absorption heating mode, the high-temperature side heat medium heated in the water-refrigerant heat exchanger 13 flows into the heater core 42, as in the single cooling mode.

[0288] In the interior air conditioning unit 30 in the outside air heat absorption heating mode, the air blown from the interior blower 32 passes through the interior evaporator 18. The air that has passed through the interior evaporator 18 is heated by the heater core 42 depending on the opening degree of the air mix door 34. The conditioned air, whose temperature has been adjusted to approach the target outlet temperature TAO, is then blown into the vehicle cabin. This achieves heating of the vehicle cabin.

[0289] (4-2) HG Heating Mode In the HG heating mode, the control device 60 executes the control flow for the HG heating mode shown in FIG.

[0290] First, in step S2801, the target high-temperature-side heat medium temperature TWHO of the high-temperature-side heat medium is determined, as in the HG dehumidifying and heating mode. Then, in step S2802, the increase / decrease amount ΔIVO of the rotation speed of the compressor 11 is determined, as in the HG dehumidifying and heating mode.

[0291] In step S2803, a target differential pressure ΔPO is determined. The target differential pressure ΔPO is a target value of the actual differential pressure ΔP of the heat pump cycle 10. The actual differential pressure ΔP can be calculated by subtracting the chiller-side refrigerant pressure Pc from the discharge refrigerant pressure Pd detected by the discharge refrigerant temperature and pressure sensor 62a. The target differential pressure ΔPO is a value obtained by subtracting the target low pressure PSO from the target high pressure PDO, which is the target value of the discharge refrigerant pressure Pd.

[0292] The target high-pressure PDO can be determined based on the target high-temperature-side heat medium temperature TWHO. The target low-pressure PSO is determined so that the compression work of the compressor 11 can secure heat sufficient to heat the high-temperature-side heat medium to a desired temperature.

[0293] In step S2804, the increase / decrease amount ΔEVHG of the opening degree of the bypass-side flow control valve 14d is determined. The increase / decrease amount ΔEVHG in the HG heating mode is determined by a feedback control method based on the deviation between the target differential pressure ΔPO and the actual differential pressure ΔP, etc., so that the actual differential pressure ΔP approaches the target differential pressure ΔPO.

[0294] In step S2805, the target degree of subcooling SCO1 is determined, as in the HG dehumidifying and heating mode. Then, in step S2806, the increase / decrease amount ΔEVB of the throttle opening of the cooling expansion valve 14c is determined, as in the HG dehumidifying and heating mode.

[0295] In step S2807, the opening degree SW of the air mix door 34 is calculated, similarly to the single cooling mode.

[0296] In step S2808, the control signals to be output to the heating expansion valve 14a, the cooling expansion valve 14b, the cooling expansion valve 14c, and the bypass side flow control valve 14d are determined so as to fully close the heating expansion valve 14a, fully close the cooling expansion valve 14b, throttle the cooling expansion valve 14c, and throttle the bypass side flow control valve 14d, respectively. Also, the control voltages to be output to the high pressure side opening / closing valve 22a and the low pressure side opening / closing valve 22b are determined so as to open the high pressure side opening / closing valve 22a and close the low pressure side opening / closing valve 22b, respectively.

[0297] Furthermore, the control device 60 appropriately determines the operating states of other control target devices, similarly to the single cooling mode.

[0298] In step S2809, a control signal or control voltage is output to each of the control target devices so that the control states of the various control target devices determined as described above are obtained. Then, as indicated by Z in Figures 3 and 19, the control flow returns to step S10.

[0299] 20 , the refrigerant discharged from the compressor 11 circulates in the following order: the first three-way joint 12a, the water-refrigerant heat exchanger 13, the high-pressure side passage 21a, the cooling expansion valve 14c, the chiller 20, the seventh three-way joint 12g, 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 in which the refrigerant circulates in the following order: the first three-way joint 12a, the bypass-side flow control valve 14d disposed in the bypass passage 21c, the seventh three-way joint 12g, the accumulator 23, and the suction port of the compressor 11.

[0300] Therefore, in the heat pump cycle 10 in the HG heating mode, the state of the refrigerant changes as shown in the Mollier diagram of FIG.

[0301] The flow of refrigerant discharged from the compressor 11 (point a21 in FIG. 21 ) is branched at the first three-way joint 12a. One of the refrigerant branches at the first three-way joint 12a flows into the water-refrigerant heat exchanger 13 and dissipates heat to the high-temperature side heat medium (from point a21 to point b21 in FIG. 21 ). This heats the high-temperature side heat medium.

[0302] The refrigerant flowing out of the water-refrigerant heat exchanger 13 flows into the high-pressure side passage 21a. The refrigerant flowing into the high-pressure side passage 21a passes through the fifth three-way joint 12e and flows into the cooling expansion valve 14c, where it is decompressed (from point b21 to point g21 in FIG. 21 ).

[0303] The refrigerant decompressed by the cooling expansion valve 14c flows into the chiller 20. In the HG heating mode, the low-temperature side pump 51 is stopped, so there is no heat exchange between the refrigerant and the low-temperature side heat medium in the chiller 20. The refrigerant that flows out of the chiller 20 flows into one inlet of the seventh three-way joint 12g via the sixth three-way joint 12f.

[0304] The other refrigerant branched at the first three-way joint 12a flows into a bypass passage 21c. The refrigerant flowing into the bypass passage 21c is flow-regulated and decompressed by the bypass-side flow control valve 14d (from point a21 to point i21 in FIG. 21 ). The refrigerant decompressed by the bypass-side flow control valve 14d flows into one inlet of the seventh three-way joint 12g.

[0305] At the seventh three-way joint 12g, the refrigerant flowing out from the sixth three-way joint 12f and the refrigerant flowing out from the bypass passage 21c join together and are mixed. The refrigerant flowing out from the seventh three-way joint 12g flows into the accumulator 23 via the eighth three-way joint 12h. The refrigerant flowing into the accumulator 23 is mixed more homogeneously (point j21 in Figure 21). The refrigerant flowing out from the accumulator 23 is drawn into the compressor 11 and compressed again.

[0306] In addition, in the high-temperature side heat medium circuit 40 in the HG heating mode, as shown by the solid arrow in Figure 20, the high-temperature side heat medium heated in the water-refrigerant heat exchanger 13 flows into the heater core 42, as in the single cooling mode.

[0307] In the interior air conditioning unit 30 in the HG heating mode, the temperature of the air is adjusted to approach the target outlet temperature TAO, as in the outside air heat absorption heating mode, and the interior air conditioning unit 30 blows the air into the vehicle compartment. This achieves heating of the vehicle compartment.

[0308] In the HG heating mode, the refrigerant with a relatively high enthalpy is merged with the refrigerant flowing out from the cooling-side expansion valve 14c through the bypass passage 21c. This allows the cycle to be balanced even if the amount of heat released from the refrigerant to the high-temperature side heat medium in the water-refrigerant heat exchanger 13 is increased by increasing the refrigerant discharge capacity of the compressor 11.

[0309] Therefore, in the HG heating mode, the heating capacity of the heater for the blown air can be improved more than in the outdoor air heat absorption heating mode.

[0310] (5) Cooling / Cooling Mode In the cooling / cooling mode, the control device 60 executes a control flow for the cooling / cooling mode. In the control flow for the cooling / cooling mode, the control device 60 determines the target evaporator temperature TEO, as in the single cooling mode. Furthermore, the control device 60 determines the increase / decrease amount ΔIVO of the rotation speed of the compressor 11, as in the single cooling mode.

[0311] Similarly to the single cooling mode, the control device 60 determines a target degree of subcooling SCO2 of the refrigerant flowing out from the outdoor heat exchanger 15. Furthermore, similar to the single cooling mode, the control device 60 determines an increase / decrease ΔEVC in the throttle opening of the cooling expansion valve 14b.

[0312] The control device 60 also determines a target degree of superheat SHCO of the refrigerant on the outlet side of the refrigerant passage of the chiller 20. A predetermined constant (5° C. in this embodiment) can be used as the target degree of superheat SHCO.

[0313] Furthermore, the control device 60 determines an increase / decrease amount ΔEVB of the throttle opening of the cooling expansion valve 14c. The increase / decrease amount ΔEVB in the cooling / cooling mode is determined by a feedback control method based on factors such as the deviation between the target superheat degree SHCO and the superheat degree SHC of the refrigerant flowing out of the refrigerant passage of the chiller 20 so that the superheat degree SHC of the refrigerant flowing out of the refrigerant passage of the chiller 20 approaches the target superheat degree SHCO.

[0314] The degree of superheat SHC of the refrigerant flowing out from the refrigerant passage of the chiller 20 is calculated using the chiller-side refrigerant temperature Tc and the chiller-side refrigerant pressure Pc detected by the chiller-side refrigerant temperature and pressure sensor 62e.

[0315] The control device 60 also determines a target low-temperature-side heat medium temperature TWLO of the low-temperature-side heat medium flowing out from the heat medium passage of the chiller 20. The target low-temperature-side heat medium temperature TWLO is determined based on the heat generation amount of the battery 70 and the outside air temperature Tam, by referring to a control map stored in advance in the control device 60.

[0316] In the control map for the cooling / air-cooling mode, the target low-temperature side heat medium temperature TWLO is determined to decrease with an increase in the amount of heat generated by the battery 70 and an increase in the outside air temperature Tam, so as to achieve appropriate cooling of the battery 70. Furthermore, when the first low-temperature side heat medium temperature TWL1 is lower than the target low-temperature side heat medium temperature TWLO, the control device 60 fully closes the cooling expansion valve 14c.

[0317] Furthermore, the control device 60 calculates the opening degree SW of the air mix door 34 in the same manner as in the single cooling mode.

[0318] The control device 60 determines the control signals to be output to the heating expansion valve 14 a in a fully open state, the cooling expansion valve 14 b in a throttled state, the cooling expansion valve 14 c in a throttled state, and the bypass-side flow control valve 14 d in a fully closed state. The control device 60 also determines the control voltages to be output to the high-pressure side on-off valve 22 a and the low-pressure side on-off valve 22 b in order to close them.

[0319] Furthermore, the control device 60 appropriately determines the operating states of other controlled devices. For example, the control device 60 determines the control voltages to be output to the high-temperature side pump 41 and the low-temperature side pump 51 so as to achieve a predetermined reference pumping capacity. For example, the control device 60 determines the operating state of the heat medium three-way valve 53 so that the first low-temperature side heat medium temperature TWL1 detected by the first low-temperature side heat medium temperature sensor 64a approaches the target low-temperature side heat medium temperature TWLO.

[0320] The control device 60 outputs control signals or control voltages to the various control target devices so that the control states of the various control target devices determined as described above are obtained. Then, as indicated by Z in FIG. 3, the control flow returns to step S10.

[0321] Therefore, in the heat pump cycle 10 in the cooling / cooling mode, the refrigerant discharged from the compressor 11 circulates in the following order: water-refrigerant heat exchanger 13, the fully open heating expansion valve 14a, the outdoor heat exchanger 15, the fifth three-way joint 12e, the cooling expansion valve 14b, the indoor evaporator 18, 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 in which the refrigerant discharged from the compressor 11 circulates in the following order: water-refrigerant heat exchanger 13, the fully open heating expansion valve 14a, the outdoor heat exchanger 15, the fifth three-way joint 12e, the cooling expansion valve 14c, the chiller 20, the accumulator 23, and the suction port of the compressor 11.

[0322] That is, the flow of refrigerant flowing out from the water-refrigerant heat exchanger 13 is switched to a refrigerant circuit in which the indoor evaporator 18 and the chiller 20 are connected in parallel.

[0323] Therefore, in the heat pump cycle 10 in the cooling / air-conditioning mode, a vapor compression refrigeration cycle is configured in which the water-refrigerant heat exchanger 13 and the outdoor heat exchanger 15 function as condensers, and the indoor evaporator 18 and chiller 20 function as evaporators.

[0324] In the water-refrigerant heat exchanger 13, the refrigerant dissipates heat to the high-temperature side heat medium, thereby heating the high-temperature side heat medium. In the indoor evaporator 18, the refrigerant absorbs heat from the blown air, thereby cooling the blown air. In the chiller 20, the refrigerant absorbs heat from the low-temperature side heat medium, thereby cooling the low-temperature side heat medium.

[0325] In the high-temperature side heat medium circuit 40 in the cooling / air-cooling mode, the high-temperature side heat medium heated in the water-refrigerant heat exchanger 13 flows into the heater core 42, as in the single cooling mode.

[0326] In the low-temperature side heat medium circuit 50 in the cooling / air-cooling mode, the low-temperature side heat medium cooled to approach the target low-temperature side heat medium temperature TWLO flows into the coolant passage 70a of the battery 70. The low-temperature side heat medium flows through the coolant passage 70a of the battery 70, thereby cooling the battery 70.

[0327] In addition, in the interior air conditioning unit 30 in the cooling / cooling mode, the conditioned air whose temperature has been adjusted to approach the target outlet temperature TAO is blown into the vehicle compartment, as in the single cooling mode, thereby realizing cooling of the vehicle compartment.

[0328] (6) Cooling Serial Dehumidifying Heating Mode In the cooling serial dehumidifying heating mode, the control device 60 executes the control flow for the cooling serial dehumidifying heating mode. In the control flow for the cooling serial dehumidifying heating mode, the control device 60 determines the target evaporator temperature TEO, similar to the series dehumidifying heating mode. Therefore, the control flow for the series dehumidifying heating mode includes a target evaporator temperature determination unit. Furthermore, similar to the series dehumidifying heating mode, the control device 60 determines the increase / decrease amount ΔIVO of the rotation speed of the compressor 11.

[0329] Similarly to the series dehumidifying heating mode, the controller 60 determines the target high-temperature-side heat medium temperature TWHO of the high-temperature-side heat medium. Furthermore, similar to the series dehumidifying heating mode, the controller 60 determines the amount of change ΔKPN1 in the opening degree pattern KPN1.

[0330] Similarly to the cooling and air-conditioning mode, the control device 60 determines a target degree of superheat SHCO of the refrigerant on the outlet side of the refrigerant passage of the chiller 20. Furthermore, similar to the cooling and air-conditioning mode, the control device 60 determines an increase or decrease ΔEVB in the throttle opening of the cooling expansion valve 14c.

[0331] Furthermore, the control device 60 determines the target low-temperature side heat medium temperature TWLO, similarly to the cooling / air-cooling mode.

[0332] Furthermore, the control device 60 calculates the opening degree SW of the air mix door 34 in the same manner as in the single cooling mode.

[0333] The control device 60 determines the control signals to be output to the heating expansion valve 14 a, the cooling expansion valve 14 b, the cooling expansion valve 14 c, and the bypass-side flow control valve 14 d so that the valves are throttled, throttled, and fully closed, respectively. The control device 60 also determines the control voltages to be output to the high-pressure side on-off valve 22 a, and the low-pressure side on-off valve 22 b so that the valves are closed.

[0334] Furthermore, the control device 60 appropriately determines the operating states of other control target devices in the same manner as in the cooling / air-conditioning mode.

[0335] The control device 60 outputs control signals or control voltages to the various control target devices so that the control states of the various control target devices determined as described above are obtained. Then, as indicated by Z in FIG. 3, the control flow returns to step S10.

[0336] Therefore, in the heat pump cycle 10 in the cooling-serial dehumidifying-heating mode, the refrigerant discharged from the compressor 11 circulates in the following order: water-refrigerant heat exchanger 13, heating expansion valve 14a, outdoor heat exchanger 15, cooling expansion valve 14b, indoor evaporator 18, accumulator 23, and the suction port of the compressor 11. At the same time, the system is switched to a refrigerant circuit in which the refrigerant discharged from the compressor 11 circulates in the following order: water-refrigerant heat exchanger 13, heating expansion valve 14a, outdoor heat exchanger 15, cooling expansion valve 14c, chiller 20, accumulator 23, and the suction port of the compressor 11.

[0337] That is, the flow of refrigerant flowing out from the outdoor heat exchanger 15 is switched to a refrigerant circuit in which the indoor evaporator 18 and the chiller 20 are connected in parallel.

[0338] Therefore, in the heat pump cycle 10 in the cooling series dehumidifying heating mode, a vapor compression refrigeration cycle is configured in which the water-refrigerant heat exchanger 13 functions as a condenser, and the indoor evaporator 18 and chiller 20 function as evaporators.

[0339] Furthermore, in the heat pump cycle 10 in the cooling-serial dehumidifying-heating mode, when the saturation temperature of the refrigerant in the outdoor heat exchanger 15 is higher than the outdoor air temperature Tam, the outdoor heat exchanger 15 functions as a condenser. When the saturation temperature of the refrigerant in the outdoor heat exchanger 15 is lower than the outdoor air temperature Tam, the outdoor heat exchanger 15 functions as an evaporator.

[0340] In the water-refrigerant heat exchanger 13, the refrigerant dissipates heat to the high-temperature side heat medium, thereby heating the high-temperature side heat medium. In the indoor evaporator 18, the refrigerant absorbs heat from the blown air, thereby cooling the blown air. In the chiller 20, the refrigerant absorbs heat from the low-temperature side heat medium, thereby cooling the low-temperature side heat medium.

[0341] In the high-temperature side heat medium circuit 40 in the cooling series dehumidifying and heating mode, the high-temperature side heat medium heated in the water-refrigerant heat exchanger 13 flows into the heater core 42, as in the single cooling mode.

[0342] In addition, in the low-temperature side heat medium circuit 50 in the cooling series dehumidifying and heating mode, the cooled low-temperature side heat medium flows through the coolant passage 70a of the battery 70, thereby cooling the battery 70, as in the cooling and cooling mode.

[0343] In the interior air conditioning unit 30 in the cooling serial dehumidifying and heating mode, the temperature of the air is adjusted to approach the target outlet temperature TAO, as in the serial dehumidifying and heating mode, and the interior air conditioning unit 30 thereby achieves dehumidifying and heating the vehicle cabin.

[0344] (7-1) Cooling HG Dehumidifying and Heating Mode In the cooling HG dehumidifying and heating mode, the control device 60 executes the control flow for the cooling HG dehumidifying and heating mode shown in FIG.

[0345] In steps S1601 to S1609 in Fig. 22, the control states of various control target devices are determined, similar to steps S1901 to S1909 in the HG dehumidifying and heating mode in Fig. 13. Therefore, in the cooling HG dehumidifying and heating mode, step S1607 is the target evaporator temperature determination section.

[0346] In step S1610, the target low-temperature side heat medium temperature TWLO is determined, similarly to the cooling / air-cooling mode.

[0347] In step S1611, a water temperature determination is performed. Specifically, it is determined whether the first low-temperature side heat medium temperature TWL1 is higher than the target low-temperature side heat medium temperature TWLO.

[0348] If it is determined in step S1611 that the first low-temperature side heat medium temperature TWL1 is higher than the target low-temperature side heat medium temperature TWLO, the process proceeds to step S1612. In step S1612, the control voltage to be output to the low-temperature side pump 51 is determined so as to achieve a predetermined reference pumping capacity, and the process proceeds to step S1614.

[0349] If it is determined in step S1611 that the first low-temperature side heat medium temperature TWL1 is not higher than the target low-temperature side heat medium temperature TWLO, the process proceeds to step S1613. In step S1613, it is determined to stop the low-temperature side pump 51, and the process proceeds to step S1614.

[0350] In step S1614, the control signals to be output to the heating expansion valve 14a are determined so that the heating expansion valve 14a is fully closed, the cooling expansion valve 14b is determined so that the cooling expansion valve 14c is determined so that the cooling expansion valve 14d is determined so that the bypass side flow control valve 14d is determined so that the bypass side flow control valve 14d is also determined so that the high pressure side opening / closing valve 22a is opened and the low pressure side opening / closing valve 22b is closed.

[0351] Furthermore, the control device 60 appropriately determines the operating states of other control target devices in the same manner as in the cooling / air-conditioning mode.

[0352] In step S1615, a control signal or a control voltage is output to each of the control target devices so that the control states of the various control target devices determined as described above are obtained. Then, as indicated by Z in Figures 3 and 22, the control flow returns to step S10.

[0353] Therefore, in the heat pump cycle 10 in the cooling HG dehumidifying heating mode, as shown by the solid arrow in Figure 14, the refrigerant discharged from the compressor 11 is switched to a refrigerant circuit in which it circulates in the same order as in the HG dehumidifying heating mode.

[0354] Therefore, in the heat pump cycle 10 in the cooling HG dehumidifying heating mode, the state of the refrigerant changes as shown in the Mollier diagram in Fig. 23. In the cooling HG dehumidifying heating mode, the refrigerant flowing into the chiller 20 absorbs heat from the low-temperature side heat medium (from point g23 to point h23 in Fig. 23), as opposed to the HG dehumidifying heating mode. This causes the low-temperature side heat medium to cool. Other operations of the heat pump cycle 10 are the same as in the HG dehumidifying heating mode.

[0355] In addition, in the high-temperature side heat medium circuit 40 in the cooling HG dehumidifying heating mode, as shown by the solid arrow in Figure 14, the high-temperature side heat medium heated in the water-refrigerant heat exchanger 13 flows into the heater core 42, just like in the single cooling mode.

[0356] In addition, in the low-temperature side heat medium circuit 50 in the cooling HG dehumidifying heating mode, as shown by the dashed arrow in Figure 14, the cooled low-temperature side heat medium flows through the coolant passage 70a of the battery 70, thereby cooling the battery 70, as in the cooling and air-conditioning mode.

[0357] In the interior air conditioning unit 30 in the cooling HG dehumidifying heating mode, the temperature of the conditioned air is adjusted to approach the target outlet temperature TAO, as in the HG dehumidifying heating mode, and the interior air conditioning unit 30 thereby achieves dehumidifying heating of the vehicle cabin.

[0358] In the cooling HG dehumidifying and heating mode, similarly to the HG dehumidifying and heating mode, the refrigerant discharge capacity of the compressor 11 is increased, thereby improving the heating capacity of the high-temperature side heat medium in the water-refrigerant heat exchanger 13. Therefore, in the cooling HG dehumidifying and heating mode, the battery 70 can be cooled, and the heating capacity of the blown air in the heating section can be improved compared to the cooling serial dehumidifying and heating mode.

[0359] (7-2) Cooled Outdoor Air Heat Absorption HG Dehumidifying and Heating Mode In the cooled outdoor air heat absorption HG dehumidifying and heating mode, the controller 60 executes the control flow for the cooled outdoor air heat absorption HG dehumidifying and heating mode shown in FIG.

[0360] In steps S1501 to S1511 in Fig. 24, the control states of various control target devices are determined, similar to steps S1801 to S1811 in Fig. 16 for the outdoor air heat absorption HG dehumidifying heating mode. Therefore, in the cooled outdoor air heat absorption HG dehumidifying heating mode, step S1507 is the target evaporator temperature determination section.

[0361] Furthermore, in steps S1512 to S1515 in FIG. 24, the target low-temperature side heat medium temperature TWLO and the control state of the low-temperature side pump 51 are determined, similar to steps S1610 to S1613 in FIG. 23 for the cooling HG dehumidifying heating mode.

[0362] In step S1516, the control signals to be output to the heating expansion valve 14a, the cooling expansion valve 14b, the cooling expansion valve 14c, and the bypass-side flow control valve 14d are determined so as to place them in a throttled state, a throttled state, a throttled state, and a throttled state, respectively. Also, the control voltages to be output to the high-pressure side on-off valve 22a and the low-pressure side on-off valve 22b are determined so as to open and close, respectively.

[0363] Furthermore, the control device 60 appropriately determines the operating states of other control target devices in the same manner as in the cooling / air-conditioning mode.

[0364] In step S1517, a control signal or a control voltage is output to each of the control target devices so that the control states of the various control target devices determined as described above are obtained. Then, as indicated by Z in Figures 3 and 24, the control flow returns to step S10.

[0365] Therefore, in the heat pump cycle 10 in the cooled outdoor air heat absorption HG dehumidification heating mode, as shown by the solid arrow in Figure 17, the refrigerant discharged from the compressor 11 is switched to a refrigerant circuit that circulates in the same order as in the outdoor air heat absorption HG dehumidification heating mode.

[0366] Therefore, in the heat pump cycle 10 in the cooled outdoor air heat absorption HG dehumidifying heating mode, the state of the refrigerant changes as shown in the Mollier diagram in Fig. 25. In the cooled outdoor air heat absorption HG dehumidifying heating mode, the refrigerant flowing into the chiller 20 absorbs heat from the low-temperature side heat medium (from point g25 to point h25 in Fig. 25), as opposed to the outdoor air heat absorption HG dehumidifying heating mode. This causes the low-temperature side heat medium to cool. Other operations of the heat pump cycle 10 are the same as in the outdoor air heat absorption HG dehumidifying heating mode.

[0367] In addition, in the high-temperature side heat medium circuit 40 in the cooled outside air heat absorption HG dehumidifying heating mode, as shown by the solid arrow in Figure 17, the high-temperature side heat medium heated in the water-refrigerant heat exchanger 13 flows into the heater core 42, just like in the single cooling mode.

[0368] In addition, in the low-temperature side heat medium circuit 50 in the cooled outside air heat absorption HG dehumidifying heating mode, as shown by the dashed arrow in Figure 17, the cooled low-temperature side heat medium flows through the coolant passage 70a of the battery 70, thereby cooling the battery 70, similar to the cooling and air-conditioning mode.

[0369] In the interior air-conditioning unit 30 in the cooled outside air heat absorption HG dehumidifying and heating mode, the conditioned air whose temperature has been adjusted to approach the target outlet temperature TAO is blown into the vehicle cabin, as in the outside air heat absorption HG dehumidifying and heating mode, thereby realizing dehumidifying and heating the vehicle cabin.

[0370] In the cooled outside air heat absorption HG dehumidifying heating mode, similar to the cooled HG dehumidifying heating mode, the battery 70 is cooled, and at the same time, the heating capacity of the blown air in the heating section can be improved more than in the cooled series dehumidifying heating mode.

[0371] Furthermore, in the cooled outdoor air heat absorption HG dehumidifying heating mode, the blown air can be heated using heat absorbed by the refrigerant from the outdoor air in the outdoor heat exchanger 15. Therefore, in the cooled outdoor air heat absorption HG dehumidifying heating mode, the operating efficiency of the heat pump cycle 10 can be improved more than in the cooled outdoor air heat absorption HG dehumidifying heating mode.

[0372] (8) Cooling Device Heat Endoscopy Heating Mode In the cooling device heat endoscopy heating mode, the control device 60 executes a control flow for the cooling device heat endoscopy heating mode. In the control flow for the cooling device heat endoscopy heating mode, the control device 60 determines the target low-temperature side heat medium temperature TWLO, similar to the cooling / air-cooling mode.

[0373] Furthermore, the control device 60 determines an increase / decrease amount ΔIVO of the rotation speed of the compressor 11. The increase / decrease amount ΔIVO in the cooling equipment endothermic heating mode is determined by a feedback control method based on the deviation between the target low-temperature side heat medium temperature TWLO and the first low-temperature side heat medium temperature TWL1, etc., so that the first low-temperature side heat medium temperature TWL1 approaches the target low-temperature side heat medium temperature TWLO.

[0374] Furthermore, the control device 60 determines the target degree of subcooling SCO2 of the refrigerant flowing out from the outdoor heat exchanger 15, as in the single cooling mode.

[0375] Furthermore, the control device 60 determines an increase or decrease ΔEVB in the throttle opening of the cooling expansion valve 14c. The increase or decrease ΔEVB in the cooling equipment endothermic heating mode is determined by a feedback control method based on the deviation between the target subcooling degree SCO2 and the subcooling degree SC2 of the refrigerant flowing out of the outdoor heat exchanger 15, so that the subcooling degree SC2 of the refrigerant flowing out of the water-refrigerant heat exchanger 13 approaches the target subcooling degree SCO2.

[0376] Furthermore, the control device 60 calculates the opening degree SW of the air mix door 34 in the same manner as in the single cooling mode.

[0377] The control device 60 determines the control signals to be output to the heating expansion valve 14 a, the cooling expansion valve 14 b, the cooling expansion valve 14 c, and the bypass-side flow control valve 14 d so that the heating expansion valve 14 a is fully open, the cooling expansion valve 14 b is fully closed, the cooling expansion valve 14 c is throttled, and the bypass-side flow control valve 14 d is fully closed. The control device 60 also determines the control voltages to be output to the high-pressure side opening / closing valve 22 a and the low-pressure side opening / closing valve 22 b so that the high-pressure side opening / closing valve 22 a and the low-pressure side opening / closing valve 22 b are closed.

[0378] Furthermore, the control device 60 appropriately determines the operating states of other control target devices in the same manner as in the cooling / air-conditioning mode.

[0379] The control device 60 outputs control signals or control voltages to the various control target devices so that the control states of the various control target devices determined as described above are obtained. Then, as indicated by Z in FIG. 3, the control flow returns to step S10.

[0380] Therefore, in the heat pump cycle 10 in the cooling equipment heat absorption heating mode, the refrigerant discharged from the compressor 11 is switched to a refrigerant circuit in which it circulates in the following order: the water-refrigerant heat exchanger 13, the fully open heating expansion valve 14a, the outdoor heat exchanger 15, the cooling expansion valve 14c, the chiller 20, the accumulator 23, and the intake port of the compressor 11.

[0381] Therefore, in the heat pump cycle 10 in the cooling equipment heat absorption heating mode, a vapor compression refrigeration cycle is configured in which the water-refrigerant heat exchanger 13 and the outdoor heat exchanger 15 function as condensers and the chiller 20 functions as an evaporator.

[0382] In the water-refrigerant heat exchanger 13, the refrigerant dissipates heat to the high-temperature side heat medium, thereby heating the high-temperature side heat medium. In the chiller 20, the refrigerant absorbs heat from the low-temperature side heat medium, thereby cooling the low-temperature side heat medium.

[0383] In the high-temperature side heat medium circuit 40 in the cooling equipment heat absorption heating mode, the high-temperature side heat medium heated in the water-refrigerant heat exchanger 13 flows into the heater core 42, as in the single cooling mode.

[0384] In addition, in the low-temperature side heat medium circuit 50 in the cooling equipment heat absorption heating mode, the cooled low-temperature side heat medium flows through the coolant passage 70a of the battery 70, thereby cooling the battery 70, as in the cooling / cooling mode.

[0385] In the interior air conditioning unit 30 in the cooling device heat absorption heating mode, the temperature of the conditioned air is adjusted to approach the target outlet temperature TAO, as in the outside air heat absorption heating mode, and the interior of the vehicle is thereby heated.

[0386] (9) Cooled Outdoor Air Heat Endoscopy Heating Mode In the cooled outdoor air heat endoscopy heating mode, the control device 60 executes a control flow for the cooled outdoor air heat endoscopy heating mode. In the control flow for the cooled outdoor air heat endoscopy heating mode, the control device 60 determines the target low-temperature side heat medium temperature TWLO, similar to the cooling air-conditioning mode.

[0387] Furthermore, the control device 60 determines an increase / decrease amount ΔIVO of the rotation speed of the compressor 11. The increase / decrease amount ΔIVO in the cooled outside air heat absorption heating mode is determined by a feedback control method based on the deviation between the target low-temperature side heat medium temperature TWLO and the first low-temperature side heat medium temperature TWL1, etc., so that the first low-temperature side heat medium temperature TWL1 approaches the target low-temperature side heat medium temperature TWLO.

[0388] Similarly to the series dehumidifying heating mode, the controller 60 determines the target high-temperature-side heat medium temperature TWHO of the high-temperature-side heat medium. Furthermore, the controller 60 determines the amount of change ΔKPN2 in the opening degree pattern KPN2.

[0389] The opening pattern KPN2 is a parameter for determining a combination of the throttle opening of the heating expansion valve 14 a and the throttle opening of the cooling expansion valve 14 c. The opening pattern KPN2 corresponds to the ratio of the throttle opening of the cooling expansion valve 14 c to the throttle opening of the heating expansion valve 14 a.

[0390] In the control map for the cooled outside air heat absorption heating mode, the opening pattern KPN2 is increased as the target blown air temperature TAO increases. That is, as the target blown air temperature TAO increases, the opening ratio of the cooling expansion valve 14c to the heating expansion valve 14a is increased.

[0391] Furthermore, the control device 60 calculates the opening degree SW of the air mix door 34 in the same manner as in the single cooling mode.

[0392] The control device 60 determines the control signals to be output to the heating expansion valve 14 a in a throttled state, the cooling expansion valve 14 b in a fully closed state, the cooling expansion valve 14 c in a throttled state, and the bypass-side flow control valve 14 d in a fully closed state. The control device 60 also determines the control voltages to be output to the high-pressure side on-off valve 22 a and the low-pressure side on-off valve 22 b so that they are closed.

[0393] Furthermore, the control device 60 appropriately determines the operating states of other control target devices in the same manner as in the cooling / air-conditioning mode.

[0394] The control device 60 outputs control signals or control voltages to the various control target devices so that the control states of the various control target devices determined as described above are obtained. Then, as indicated by Z in FIG. 3, the control flow returns to step S10.

[0395] Therefore, in the heat pump cycle 10 in the cooled outdoor air heat absorption heating mode, the refrigerant discharged from the compressor 11 is switched to a refrigerant circuit in which it circulates in the following order: the water-refrigerant heat exchanger 13, the heating expansion valve 14a, the outdoor heat exchanger 15, the cooling expansion valve 14c, the chiller 20, the accumulator 23, and the intake port of the compressor 11.

[0396] Therefore, in the heat pump cycle 10 in the cooled outdoor air heat absorption heating mode, a vapor compression refrigeration cycle is configured in which the water-refrigerant heat exchanger 13 functions as a condenser and the chiller 20 functions as an evaporator.

[0397] Furthermore, in the heat pump cycle 10 in the cooled outdoor air heat absorption heating mode, when the saturation temperature of the refrigerant in the outdoor heat exchanger 15 is higher than the outdoor air temperature Tam, the outdoor heat exchanger 15 functions as a condenser. When the saturation temperature of the refrigerant in the outdoor heat exchanger 15 is lower than the outdoor air temperature Tam, the outdoor heat exchanger 15 functions as an evaporator.

[0398] In the water-refrigerant heat exchanger 13, the refrigerant dissipates heat to the high-temperature side heat medium, thereby heating the high-temperature side heat medium. In the chiller 20, the refrigerant absorbs heat from the low-temperature side heat medium, thereby cooling the low-temperature side heat medium.

[0399] In the high-temperature side heat medium circuit 40 in the cooled outside air heat absorption heating mode, the high-temperature side heat medium heated in the water-refrigerant heat exchanger 13 flows into the heater core 42, as in the single cooling mode.

[0400] In addition, in the low-temperature side heat medium circuit 50 in the cooled outside air heat absorption heating mode, the cooled low-temperature side heat medium flows through the coolant passage 70a of the battery 70, thereby cooling the battery 70, as in the cooling and cooling mode.

[0401] In addition, in the cooled outside air heat absorption heating mode, the interior air conditioning unit 30 blows conditioned air into the vehicle compartment at a temperature adjusted to approach the target outlet temperature TAO, as in the outside air heat absorption heating mode, thereby realizing heating of the vehicle compartment.

[0402] (10-1) Cooling HG Heating Mode In the cooling HG heating mode, the control device 60 executes the control flow for the cooling HG heating mode shown in FIG.

[0403] In steps S3601 to S3602 in Fig. 26, the target high-temperature-side heat medium temperature TWHO and the increase / decrease amount ΔIVO of the rotation speed of the compressor 11 are determined, similar to steps S1901 to S1902 in Fig. 13 for the HG dehumidifying and heating mode. In steps S3603 to S3607 in Fig. 26, the control states of various controlled devices are determined, similar to steps S1905 to S1909 in Fig. 13 for the HG dehumidifying and heating mode. Therefore, in the cooling HG heating mode, step S3605 is the target evaporator temperature determination unit.

[0404] In step S3608, the control signals to be output to the heating expansion valve 14a, the cooling expansion valve 14b, the cooling expansion valve 14c, and the bypass side flow control valve 14d are determined so as to fully close the heating expansion valve 14a, fully close the cooling expansion valve 14b, throttle the cooling expansion valve 14c, and throttle the bypass side flow control valve 14d, respectively. Also, the control voltages to be output to the high pressure side opening / closing valve 22a and the low pressure side opening / closing valve 22b are determined so as to open the high pressure side opening / closing valve 22a and close the low pressure side opening / closing valve 22b, respectively.

[0405] Furthermore, the control device 60 appropriately determines the operating states of other control target devices in the same manner as in the cooling / air-conditioning mode.

[0406] In step S3609, a control signal or control voltage is output to each of the control target devices so that the control states of the various control target devices determined as described above are obtained. Then, as indicated by Z in Figures 3 and 26, the control flow returns to step S10.

[0407] Therefore, in the heat pump cycle 10 in the cooling HG heating mode, as shown by the solid arrow in Figure 20, the refrigerant discharged from the compressor 11 is switched to a refrigerant circuit in which it circulates in the same order as in the HG heating mode.

[0408] Therefore, in the heat pump cycle 10 in the cooling HG heating mode, the state of the refrigerant changes as shown in the Mollier diagram of Fig. 27. In the cooling HG heating mode, unlike the HG heating mode, the refrigerant flowing into the chiller 20 absorbs heat from the low-temperature side heat medium (from point g27 to point h27 in Fig. 27). This cools the low-temperature side heat medium. Other operations of the heat pump cycle 10 are the same as in the HG heating mode.

[0409] In addition, in the high-temperature side heat medium circuit 40 in the cooling HG heating mode, as shown by the solid arrow in Figure 20, the high-temperature side heat medium heated in the water-refrigerant heat exchanger 13 flows into the heater core 42, as in the single cooling mode.

[0410] In addition, in the low-temperature side heat medium circuit 50 in the cooling HG heating mode, as shown by the dashed arrow in Figure 20, the cooled low-temperature side heat medium flows through the coolant passage 70a of the battery 70, thereby cooling the battery 70, similar to the cooling air-conditioning mode.

[0411] In addition, in the cooling HG heating mode, the interior air conditioning unit 30 blows conditioned air into the vehicle compartment whose temperature has been adjusted to approach the target outlet temperature TAO, as in the HG heating mode, thereby achieving heating of the vehicle compartment.

[0412] In the cooling HG heating mode, similarly to the HG heating mode, the cycle can be balanced even if the heating capacity of the high-temperature side heat medium in the water-refrigerant heat exchanger 13 is improved by increasing the refrigerant discharge capacity of the compressor 11. Therefore, in the cooling HG heating mode, the battery 70 is cooled, and at the same time, the heating capacity of the blown air in the heating section can be improved more than in the cooling outside air heat absorption heating mode.

[0413] (10-2) Cooled Outdoor Air Heat Absorption HG Heating Mode In the cooled outdoor air heat absorption HG heating mode, the controller 60 executes the control flow for the cooled outdoor air heat absorption HG heating mode shown in FIG.

[0414] In steps S3501 to S3506 in Fig. 28, the control states of various control target devices are determined, similar to steps S3601 to S3606 in Fig. 26 for the cooling HG heating mode. Therefore, in the cooling outside air heat absorption HG heating mode, step S3505 is the target evaporator temperature determination section.

[0415] In step S3507, a target degree of superheat SHO2 is determined for the refrigerant on the outlet side of the outdoor heat exchanger 15. A predetermined constant (5° C. in this embodiment) can be used as the target degree of superheat SHO2.

[0416] In step S3508, the increase / decrease amount ΔEVH of the throttle opening of the heating expansion valve 14a is determined. The increase / decrease amount ΔEVH in the cooled outdoor air heat absorption HG heating mode is determined by a feedback control method based on the deviation between the target superheat degree SHO2 and the superheat degree SH2 of the refrigerant on the outlet side of the outdoor heat exchanger 15, etc., so that the superheat degree SH2 of the refrigerant on the outlet side of the outdoor heat exchanger 15 approaches the target superheat degree SHO2.

[0417] In step S3509, the opening degree SW of the air mix door 34 is calculated, similarly to the single cooling mode.

[0418] In step S3510, the control signals to be output to the heating expansion valve 14a are determined so that the heating expansion valve 14a is throttled, the cooling expansion valve 14b is fully closed, the cooling expansion valve 14c is throttled, and the bypass side flow control valve 14d is throttled. Also, the control voltages to be output to the high pressure side opening / closing valve 22a are determined so that the high pressure side opening / closing valve 22b is opened and the low pressure side opening / closing valve 22b is closed.

[0419] Furthermore, the control device 60 appropriately determines the operating states of other control target devices in the same manner as in the cooling / air-conditioning mode.

[0420] In step S3511, a control signal or a control voltage is output to each of the control target devices so that the control states of the various control target devices determined as described above are obtained. Then, as indicated by Z in Figures 3 and 28, the control flow returns to step S10.

[0421] Therefore, in the heat pump cycle 10 in the cooled outdoor air heat absorption HG heating mode, the refrigerant discharged from the compressor 11 circulates in the same order as in the HG heating mode, as shown by the solid arrows in Fig. 29. At the same time, the refrigerant discharged from the compressor 11 is switched to a refrigerant circuit in which it circulates through the first three-way joint 12a, the water-refrigerant heat exchanger 13, the second three-way joint 12b, the heating expansion valve 14a, the outdoor heat exchanger 15, the low-pressure side passage 21b, the accumulator 23, and the suction port of the compressor 11, in that order.

[0422] That is, the outdoor heat exchanger 15 and the chiller 20 are connected in parallel to the flow of refrigerant flowing out of the water-refrigerant heat exchanger 13. Therefore, in the heat pump cycle 10 in the cooled outdoor air heat absorption HG heating mode, the state of the refrigerant changes as shown in the Mollier diagram of FIG.

[0423] In the cooled outside air heat absorption HG heating mode, unlike the HG heating mode, the flow of refrigerant flowing out of water-refrigerant heat exchanger 13 is branched at second three-way joint 12b. One of the refrigerants flowing out from one outlet of second three-way joint 12b flows into heating expansion valve 14a and is decompressed (from point b30 to point c30 in Figure 30).

[0424] The refrigerant decompressed by the heating expansion valve 14a flows into the outdoor heat exchanger 15. The refrigerant that has flowed into the outdoor heat exchanger 15 absorbs heat from the outside air and evaporates (from point c30 to point d30 in Figure 30). The refrigerant that has flowed out of the outdoor heat exchanger 15 flows through the low-pressure side passage 21b into one inlet of the eighth three-way joint 12h.

[0425] Furthermore, in the cooled outdoor air heat absorption HG heating mode, the refrigerant flowing into the chiller 20 absorbs heat from the low-temperature side heat medium (from point g30 to point h30 in FIG. 30 ), thereby cooling the low-temperature side heat medium. Other operations of the heat pump cycle 10 are the same as those in the HG heating mode.

[0426] In addition, in the high-temperature side heat medium circuit 40 in the cooled outside air heat absorption HG heating mode, as shown by the solid arrow in Figure 29, the high-temperature side heat medium heated in the water-refrigerant heat exchanger 13 flows into the heater core 42, as in the single cooling mode.

[0427] In addition, in the low-temperature side heat medium circuit 50 in the cooled outside air heat absorption HG heating mode, as shown by the dashed arrow in Figure 29, the cooled low-temperature side heat medium flows through the coolant passage 70a of the battery 70, thereby cooling the battery 70, similar to the cooling / cooling mode.

[0428] In the interior air-conditioning unit 30 in the cooled outside air heat absorption HG heating mode, the conditioned air whose temperature has been adjusted to approach the target outlet temperature TAO is blown into the vehicle compartment, as in the HG heating mode, thereby realizing heating of the vehicle compartment.

[0429] In the cooled outside air heat absorption HG heating mode, similar to the cooled outside air heat absorption heating mode, the battery 70 is cooled, and at the same time, the heating capacity of the blown air in the heating section can be improved more than in the cooled outside air heat absorption heating mode.

[0430] Furthermore, in the cooled outdoor air heat absorption HG heating mode, the blown air can be heated using heat absorbed from the outdoor air by the refrigerant in the outdoor heat exchanger 15. Therefore, in the cooled outdoor air heat absorption HG heating mode, the operating efficiency of the heat pump cycle 10 can be improved more than in the cooled outdoor air heat absorption HG heating mode.

[0431] (11) Cooling Mode In the cooling mode, the control device 60 executes a control flow for the cooling mode. In the control flow for the cooling mode, the control device 60 determines the target low-temperature side heat medium temperature TWLO and the increase / decrease amount ΔIVO of the rotation speed of the compressor 11, as in the cooling device endothermic heating mode. In addition, the control device 60 determines the target degree of subcooling SCO2 and the increase / decrease amount ΔEVB of the throttle opening of the cooling expansion valve 14c, as in the cooling device endothermic heating mode.

[0432] The control device 60 also determines the opening degree SW of the air mix door 34 to be 0%. That is, the control device 60 determines the control signal to be output to the actuator for driving the air mix door 34 so that the air mix door 34 is displaced to the Max Cool position.

[0433] The control device 60 determines the control signals to be output to the heating expansion valve 14 a, the cooling expansion valve 14 b, the cooling expansion valve 14 c, and the bypass-side flow control valve 14 d so that the heating expansion valve 14 a is fully open, the cooling expansion valve 14 b is fully closed, the cooling expansion valve 14 c is throttled, and the bypass-side flow control valve 14 d is fully closed. The control device 60 also determines the control voltages to be output to the high-pressure side opening / closing valve 22 a and the low-pressure side opening / closing valve 22 b so that the high-pressure side opening / closing valve 22 a and the low-pressure side opening / closing valve 22 b are closed.

[0434] Furthermore, the control device 60 appropriately determines the operation states of other control target devices in the same manner as in the cooling / air-conditioning mode. For example, the control device 60 stops the indoor blower 32.

[0435] The control device 60 outputs control signals or control voltages to the various control target devices so that the control states of the various control target devices determined as described above are obtained. Then, as indicated by Z in FIG. 3, the control flow returns to step S10.

[0436] Therefore, in the heat pump cycle 10 in cooling mode, the refrigerant discharged from the compressor 11 is switched to a refrigerant circuit in which it circulates in the following order: the water-refrigerant heat exchanger 13, the fully open heating expansion valve 14a, the outdoor heat exchanger 15, the cooling expansion valve 14c, the chiller 20, the accumulator 23, and the intake port of the compressor 11.

[0437] Therefore, in the heat pump cycle 10 in the cooling mode, a vapor compression refrigeration cycle is configured in which the outdoor heat exchanger 15 functions as a condenser and the chiller 20 functions as an evaporator. In the cooling mode, the opening degree SW of the air mix door 34 is set to 0%. Therefore, when the temperature of the high-temperature side heat medium becomes the same as that of the refrigerant, heat exchange between the refrigerant and the high-temperature side heat medium in the water-refrigerant heat exchanger 13 no longer occurs.

[0438] In the outdoor heat exchanger 15, the heat of the refrigerant is dissipated to the outside air. In the chiller 20, the refrigerant absorbs heat from the low-temperature side heat medium, thereby cooling the low-temperature side heat medium.

[0439] In the low-temperature side heat medium circuit 50 in the cooling mode, the cooled low-temperature side heat medium flows through the coolant passage 70a of the battery 70, thereby cooling the battery 70, as in the cooling / air-conditioning mode.

[0440] (12) Fan Mode In the fan mode, the control device 60 stops the compressor 11. The control device 60 also operates the indoor fan 32 in response to a setting signal set by the air volume setting switch.

[0441] In the indoor air conditioning unit 30 in the blowing mode, the air blown from the indoor blower 32 is blown into the room.

[0442] As described above, the vehicle air conditioner 1 of this embodiment can achieve comfortable air conditioning in the vehicle cabin while appropriately adjusting the temperature of the battery 70 by switching between various operation modes.

[0443] Furthermore, in the vehicle air conditioner 1 of this embodiment, when performing dehumidifying and heating of the vehicle cabin, the temperature of the blown air can be continuously adjusted over a wide range while suppressing a decrease in operating efficiency. More specifically, the vehicle air conditioner 1 of this embodiment has the following dehumidifying and heating modes: (2) serial dehumidifying and heating mode, and (3-1) HG dehumidifying and heating mode.

[0444] In the heat pump cycle 10 in the serial dehumidifying heating mode, by changing the opening pattern KPN1, the refrigerant evaporation temperature in the indoor evaporator 18 can be maintained at a temperature that can suppress frost formation on the indoor evaporator 18 while changing the refrigerant pressure in the outdoor heat exchanger 15.

[0445] As a result, in the serial dehumidifying heating mode, it is possible to adjust the amount of heat exchanged between the refrigerant and the outside air in the outdoor heat exchanger 15 while suppressing frost formation on the indoor evaporator 18. Therefore, by adjusting the amount of heat dissipated from the refrigerant to the high-temperature side heat medium in the water-refrigerant heat exchanger 13, it is possible to continuously adjust the heating capacity of the heater core 42 for the blown air.

[0446] In the heat pump cycle 10 in the HG dehumidifying heating mode, by increasing the refrigerant discharge capacity of the compressor 11, it is possible to suppress frost formation on the indoor evaporator 18 while improving the heating capacity of the blown air in the heater core 42 more than in the serial dehumidifying heating mode.

[0447] Furthermore, in the heat pump cycle 10 in the HG dehumidifying heating mode, the increase in compression work when the refrigerant discharge capacity of the compressor 11 is increased can be effectively used as a heating source for the blown air. Therefore, when the heating capacity of the heating section for the blown air is improved, a decrease in operating efficiency can be suppressed.

[0448] As a result, in the vehicle air conditioning system 1 of this embodiment, when dehumidifying and heating the passenger compartment, by switching between the serial dehumidifying and heating mode and the HG dehumidifying and heating mode, the temperature of the blown air can be continuously adjusted over a wide range while suppressing a decrease in operating efficiency.

[0449] In addition, in the vehicle air conditioner 1 of this embodiment, as shown in step S90 of Fig. 3, when the target blow-out temperature TAO is lower than the dehumidification reference temperature β1, the mode can be switched from the HG dehumidifying and heating mode to the series dehumidifying and heating mode. Also, when the target blow-out temperature TAO is equal to or higher than the dehumidifying reference temperature β1, the mode can be switched from the series dehumidifying and heating mode to the HG dehumidifying and heating mode.

[0450] This allows reliable switching between the HG dehumidifying and heating mode and the serial dehumidifying and heating mode with simple control.

[0451] The vehicle air conditioner 1 of this embodiment also has a dehumidifying and heating mode (3-2) called the outside air heat absorption HG dehumidifying and heating mode. In the outside air heat absorption HG dehumidifying and heating mode, the heat of the outside air can be used to heat the blown air. This reduces the power consumption of the compressor 11 compared to the HG dehumidifying and heating mode, further suppressing the decrease in operating efficiency.

[0452] 5 and 11, the vehicle air conditioner 1 of this embodiment uses the target evaporator temperature TEO as the outdoor unit temperature Tout. When the outdoor unit temperature difference ΔTO becomes equal to or greater than the first reference temperature difference KΔTO1, the mode is switched from the HG dehumidifying and heating mode to the outside air heat absorption HG dehumidifying and heating mode.

[0453] This allows switching from the HG dehumidifying and heating mode to the outdoor air heat absorption HG dehumidifying and heating mode when the temperature of the refrigerant flowing into the outdoor heat exchanger 15 is lower than the outdoor air temperature Tam. In other words, when the refrigerant can reliably absorb the heat of the outdoor air in the outdoor heat exchanger 15, switching from the HG dehumidifying and heating mode to the outdoor air heat absorption HG dehumidifying and heating mode is possible.

[0454] Similarly, when the outdoor unit temperature difference ΔTO becomes equal to or greater than the first reference temperature difference KΔTO1, the mode is switched from the cooling HG dehumidifying heating mode to the cooling outdoor air heat absorption HG dehumidifying heating mode. This allows the mode to be switched from the cooling HG dehumidifying heating mode to the cooling outdoor air heat absorption HG dehumidifying heating mode when the refrigerant in the outdoor heat exchanger 15 is able to reliably absorb heat from the outdoor air.

[0455] The vehicle air conditioner 1 of this embodiment also has, as dehumidifying and heating modes, (6) a cooling serial dehumidifying and heating mode and (7-1) a cooling HG dehumidifying and heating mode.

[0456] Therefore, in the vehicle air conditioning system 1 of this embodiment, when dehumidifying and heating the passenger compartment, by switching between the cooling series dehumidifying and heating mode and the cooling HG dehumidifying and heating mode, it is possible to cool the battery 70 while simultaneously suppressing a decrease in operating efficiency and continuously adjust the temperature of the blown air over a wide range.

[0457] Furthermore, the vehicle air conditioner 1 of this embodiment can continuously adjust the temperature of the blown air over a wide range while suppressing a decrease in operating efficiency when heating the vehicle cabin. More specifically, the vehicle air conditioner 1 of this embodiment has two heating modes: (4-1) an outside air heat absorption heating mode and (4-2) an HG heating mode.

[0458] In the heat pump cycle 10 in the heating mode, the amount of heat released from the refrigerant to the high-temperature side heat medium in the water-refrigerant heat exchanger 13 can be adjusted by adjusting at least one of the refrigerant discharge capacity of the compressor 11 and the throttle opening of the heating expansion valve 14a. Therefore, the heating capacity of the heater core 42 for heating the blown air can be continuously adjusted.

[0459] In addition, in the heat pump cycle 10 in the HG heating mode, the refrigerant discharge capacity of the compressor 11 is increased, so that the heating capacity of the heater core 42 for heating the blown air can be improved more than in the heating mode.

[0460] Furthermore, in the heat pump cycle 10 in the HG heating mode, the increase in the compression work amount that occurs when the refrigerant discharge capacity of the compressor 11 is increased can be effectively used as a heating source for the blown air. Therefore, when the heating capacity of the heating section for the blown air is improved, a decrease in operating efficiency can be suppressed.

[0461] As a result, in the vehicle air conditioning system 1 of this embodiment, when heating the vehicle cabin, by switching between the outside air heat absorption heating mode and the HG heating mode, the temperature of the blown air can be continuously adjusted over a wide range while suppressing a decrease in operating efficiency.

[0462] 6, the vehicle air conditioner 1 of this embodiment can switch from the HG heating mode to the outside air heat absorption heating mode when the target blown air temperature TAO is lower than the hot gas reference temperature δ. Also, when the target blown air temperature TAO is equal to or higher than the hot gas reference temperature δ, the vehicle air conditioner 1 can switch from the outside air heat absorption heating mode to the HG heating mode.

[0463] This allows switching between the outdoor air heat absorption heating mode and the HG heating mode reliably with simple control.

[0464] In the HG heating mode, the heating capacity of the heater can be adjusted over a wide range by adjusting the refrigerant discharge capacity of the compressor 11. Furthermore, in the outdoor air heat absorption heating mode, the refrigerant absorbs heat from the outdoor air to heat the air being blown, making it easier to improve operating efficiency than in the HG heating mode. Therefore, being able to reliably switch from the HG heating mode to the outdoor air heat absorption heating mode is effective in preventing a decrease in operating efficiency.

[0465] In addition, as described in step S340, the automotive air conditioner 1 of this embodiment uses the saturation temperature of the refrigerant in the target low-pressure PSO as the outdoor unit temperature Tout. When the outdoor unit temperature difference ΔTO becomes equal to or greater than the first reference temperature difference KΔTO1, the mode is switched from the cooled HG heating mode to the cooled outside air heat absorption HG heating mode.

[0466] This allows switching from the cooling HG heating mode to the cooling outdoor air heat absorption HG heating mode when the temperature of the refrigerant flowing into the outdoor heat exchanger 15 is lower than the outdoor air temperature Tam. In other words, when the refrigerant can reliably absorb heat from the outdoor air in the outdoor heat exchanger 15, switching from the cooling HG heating mode to the cooling outdoor air heat absorption HG heating mode is possible.

[0467] The vehicle air conditioner 1 of this embodiment also has, as heating modes, (9) a cooled outside air heat absorption heating mode and (10-1) a cooled HG heating mode.

[0468] Therefore, in the vehicle air conditioning system 1 of this embodiment, when heating the vehicle cabin, by switching between the cooled outside air heat absorption heating mode and the cooled HG heating mode, it is possible to cool the battery 70 while simultaneously suppressing a decrease in operating efficiency and continuously adjust the temperature of the blown air over a wide range.

[0469] Second Embodiment In this embodiment, an example will be described in which the control manner relating to switching of the operation mode in the control program is changed from that in the first embodiment.

[0470] In the control program of this embodiment, an initial operation mode is selected, similar to the control flows of Figures 3 to 12 of the first embodiment. Thereafter, a control routine is repeated at each predetermined control cycle, including reading the detection signals and operation signals, calculating the target blown air temperature TAO, selecting an operation mode based on the currently selected operation mode, and controlling various controlled devices according to the operation mode.

[0471] First, with reference to FIG. 31, the selection of the operation mode when the currently selected operation mode is (1) the single cooling mode will be described.

[0472] If it is determined that the heating capacity of the blown air is insufficient when the currently selected operation mode is (1) the single cooling mode, (2) the serial dehumidifying and heating mode is selected.

[0473] Specifically, (1) when the opening degree SW of the air mix door 34 is equal to or greater than the upper limit opening degree KSW1 (95% in this embodiment) and the blown air temperature TAV is equal to or less than the target outlet temperature TAO minus a predetermined deficiency reference value KTA1, it is determined that the heating capacity of the blown air is insufficient. Then, (2) the series dehumidifying and heating mode is selected. The deficiency reference value KTA1 is a positive value. In this embodiment, the deficiency reference value KTA1 is set to 3°C.

[0474] Next, the selection of the operation mode when the currently selected operation mode is (2) the serial dehumidifying and heating mode will be described.

[0475] If it is determined that the heating capacity of the blown air is excessive when the currently selected operation mode is (2) the serial dehumidifying heating mode, (1) the single cooling mode is selected.

[0476] Specifically, (2) during the series dehumidifying and heating mode, when the opening pattern KPN1 is equal to or greater than the upper limit opening pattern KPN1H and the blown air temperature TAV is equal to or greater than the target outlet temperature TAO plus a predetermined excess judgment reference value KTA2, it is determined that the heating capacity of the blown air is excessive. Then, (1) the standalone cooling mode is selected. The excess judgment reference value KTA2 is a positive value. In this embodiment, the excess judgment reference value KTA2 is set to 3°C.

[0477] Furthermore, when the currently selected operation mode is (2) the serial dehumidifying and heating mode, if it is determined that the heating capacity of the blown air is insufficient, (3-1) the HG dehumidifying and heating mode is selected.

[0478] Specifically, when the opening pattern KPN1 becomes equal to or lower than the reference lower limit opening pattern KPN1L while the (2) serial dehumidifying and heating mode is being executed, and the blown air temperature TAV becomes equal to or lower than the value obtained by subtracting the deficiency judgment reference value KTA1 from the target blown air temperature TAO, it is determined that the heating capacity of the blown air is insufficient, and the (3-1) HG dehumidifying and heating mode is selected.

[0479] Next, selection of an operation mode when the currently selected operation mode is (3-1) HG dehumidifying and heating mode will be described with reference to FIGS. 31 and 32.

[0480] When the currently selected operation mode is (3-1) HG dehumidifying and heating mode, if it is determined that the dehumidifying capacity of the blown air is insufficient, (2) serial dehumidifying and heating mode is selected.

[0481] Specifically, when the opening of the bypass-side flow control valve 14d is equal to or smaller than the reference opening and the evaporator temperature Tefin is equal to or larger than the target evaporator temperature TEO plus a predetermined dehumidification reference value KTE during the execution of the (3-1) HG dehumidifying and heating mode, it is determined that the dehumidifying capacity of the blown air is insufficient. Then, the (2) series dehumidifying and heating mode is selected.

[0482] The dehumidification determination reference value KTE is a positive value. In this embodiment, the dehumidification determination reference value KTE is set to 3° C. As the reference opening degree of the bypass side flow rate adjustment valve 14d, the minimum opening degree that can be realized in terms of control of the bypass side flow rate adjustment valve 14d may be used.

[0483] Furthermore, when the currently selected operating mode is (3-1) HG dehumidifying heating mode, as described in step S170 of the first embodiment, if it is determined that outdoor air heat absorption is possible, (3-2) outdoor air heat absorption HG dehumidifying heating mode is selected.

[0484] Next, selection of an operation mode when the currently selected operation mode is the (3-2) outdoor air heat absorption HG dehumidifying and heating mode will be described with reference to FIG.

[0485] When the currently selected operation mode is the (3-2) outdoor air heat absorption HG dehumidifying and heating mode, if it is determined that the dehumidifying capacity of the blown air is insufficient, the (3-1) HG dehumidifying and heating mode is selected.

[0486] Specifically, when the opening of the bypass-side flow control valve 14d is equal to or smaller than the reference opening and the evaporator temperature Tefin is equal to or larger than the target evaporator temperature TEO plus the dehumidification reference value KTE during execution of the (3-2) outside air heat absorption HG dehumidifying heating mode, it is determined that the dehumidifying capacity of the blown air is insufficient, and the (3-1) HG dehumidifying heating mode is selected.

[0487] Furthermore, when the currently selected operating mode is the (3-2) outdoor air heat absorption HG dehumidifying heating mode, as described in steps S30 and S40 of the first embodiment, if it is determined that cooling of the blown air is not necessary in the indoor evaporator 18, the (4-1) outdoor air heat absorption heating mode is selected.

[0488] Next, the selection of the operation mode when the currently selected operation mode is the outdoor air heat absorption heating mode (4-1) will be described.

[0489] When the currently selected operating mode is (4-1) outdoor air heat absorption heating mode, as described in steps S30 and S40 of the first embodiment, if it is determined that cooling of the blown air is necessary in the indoor evaporator 18, (3-2) outdoor air heat absorption HG dehumidifying heating mode is selected.

[0490] Furthermore, when the currently selected operation mode is the (4-1) outdoor air heat absorption heating mode, if it is determined that the heating capacity of the blown air is insufficient, the (4-2) HG heating mode is selected.

[0491] Specifically, when the refrigerant discharge capacity (specifically, the rotation speed) of the compressor 11 is equal to or greater than a reference value and the blown air temperature TAV is equal to or less than the target blown air temperature TAO minus the deficiency determination reference value KTA1 during the execution of the (4-1) outdoor air heat absorption heating mode, it is determined that the heating capacity of the blown air is insufficient. Then, the (4-2) HG heating mode is selected.

[0492] The reference value (specifically, the reference rotation speed) of the compressor 11 may be the maximum rotation speed determined based on the durability of the compressor 11, etc.

[0493] Next, when the currently selected operating mode is (4-2) HG heating mode, as described in step S240 of the first embodiment, if the target blow-out temperature TAO is lower than the hot gas reference temperature δ, (4-1) outdoor air heat absorption heating mode is selected.

[0494] Other control aspects related to the switching of the driving modes are the same as those in the first embodiment. In Figures 31 and 32, dashed arrows indicate the control aspects related to the switching of the driving modes that are the same as those in the first embodiment. In addition, other configurations and operations of the automotive air conditioner 1 are the same as those in the first embodiment.

[0495] In the vehicle air conditioner 1 of this embodiment, the operation mode is switched by detecting the heating capacity and defrosting capacity of the blown air, so that more comfortable air conditioning of the vehicle interior can be achieved.

[0496] Specifically, when the blown air temperature TAV becomes equal to or lower than the target outlet temperature TAO minus the deficiency determination reference value KTA1 during the series dehumidifying and heating mode, the system switches to the HG dehumidifying and heating mode. In other words, the system switches from the series dehumidifying and heating mode to the HG dehumidifying and heating mode at least when the blown air temperature TAV is lower than the target outlet temperature TAO.

[0497] This makes it possible to reliably detect that the heating capacity of the blown air is insufficient while the serial dehumidifying and heating mode is being executed, and to switch to the HG dehumidifying and heating mode, which has a higher heating capacity of the blown air than the serial dehumidifying and heating mode.

[0498] Furthermore, when the evaporator temperature Tefin becomes equal to or greater than the sum of the target evaporator temperature TEO and the dehumidification reference value KTE during the HG dehumidifying and heating mode, the mode is switched to the series dehumidifying and heating mode. In other words, when the evaporator temperature Tefin is higher than the target evaporator temperature TEO, the mode is switched from the HG dehumidifying and heating mode to the series dehumidifying and heating mode.

[0499] This makes it possible to reliably detect that the dehumidifying capacity of the blown air is insufficient while the HG dehumidifying heating mode is being executed, and to switch to the serial dehumidifying heating mode, which has a higher dehumidifying capacity of the blown air than the HG dehumidifying heating mode.

[0500] Furthermore, when the evaporator temperature Tefin becomes equal to or greater than the sum of the target evaporator temperature TEO and the dehumidification reference value KTE during execution of the outdoor air heat absorption HG dehumidifying heating mode, the mode is switched to the HG dehumidifying heating mode. In other words, when at least the evaporator temperature Tefin is higher than the target evaporator temperature TEO, the mode is switched from the outdoor air heat absorption HG dehumidifying heating mode to the HG dehumidifying heating mode.

[0501] This makes it possible to reliably detect that the dehumidifying capacity of the blown air is insufficient while the outdoor air heat absorption HG dehumidifying heating mode is being executed, and to switch to the HG dehumidifying heating mode, which has a higher dehumidifying capacity of the blown air than the outdoor air heat absorption HG dehumidifying heating mode.

[0502] Furthermore, when the outside air heat absorption heating mode is in operation, if the blown air temperature TAV becomes equal to or lower than the target blown air temperature TAO minus the deficiency determination reference value KTA1, the mode is switched to the HG heating mode. In other words, the mode is switched from the outside air heat absorption heating mode to the HG heating mode at least when the blown air temperature TAV is lower than the target blown air temperature TAO.

[0503] This makes it possible to reliably detect that the heating capacity of the blown air is insufficient while the outdoor air heat absorption heating mode is being executed, and to switch to the HG heating mode, which has a higher dehumidifying capacity of the blown air than the outdoor air heat absorption heating mode.

[0504] The control mode for switching from (1) the standalone cooling mode to (2) the series dehumidifying and heating mode described in this embodiment may also be applied to switching from (5) the cooling and cooling mode to (6) the cooling and series dehumidifying and heating mode. Furthermore, the control mode for switching from (2) the series dehumidifying and heating mode to (1) the standalone cooling mode may also be applied to switching from (6) the cooling and series dehumidifying and heating mode to (5) the cooling and cooling mode.

[0505] Furthermore, the control mode when switching from the (2) series dehumidifying heating mode to the (3-1) HG dehumidifying heating mode described in this embodiment may be applied when switching from the (6) cooling series dehumidifying heating mode to the (7-1) cooling HG dehumidifying heating mode. The control mode when switching from the (3-1) HG dehumidifying heating mode to the (2) series dehumidifying heating mode may be applied when switching from the (7-1) cooling HG dehumidifying heating mode to the (6) cooling series dehumidifying heating mode.

[0506] In addition, the control mode when switching from (3-1) HG dehumidifying heating mode to (3-2) outdoor air heat absorption HG dehumidifying heating mode described in this embodiment may also be applied when switching from (7-1) cooling HG dehumidifying heating mode to (7-2) cooling outdoor air heat absorption HG dehumidifying heating mode.

[0507] Third Embodiment In this embodiment, an example will be described in which a refrigeration cycle device according to the present disclosure is applied to a vehicle air conditioner 1a shown in the overall configuration diagram of Fig. 33. The vehicle air conditioner 1a includes a heat pump cycle 10a. In Fig. 33, for clarity, a group of control sensors is omitted from the illustration.

[0508] In the heat pump cycle 10a, the accumulator 23 and the like are eliminated from the heat pump cycle 10 described in the first embodiment, and a receiver 24 and the like are adopted.

[0509] In the heat pump cycle 10a, the other outlet of the second three-way joint 12b is connected to the inlet side of the receiver 24. The refrigerant passage from the other outlet of the second three-way joint 12b to the inlet of the receiver 24 is an inlet-side passage 21d. A first inlet-side on-off valve 22c and a fourth three-way joint 12d are arranged in the inlet-side passage 21d.

[0510] The receiver 24 is a high-pressure gas-liquid separator that separates the refrigerant that flows into it into gas and liquid phases and stores the separated liquid phase refrigerant as surplus refrigerant for the cycle. The receiver 24 allows a portion of the separated liquid phase refrigerant to flow downstream from a liquid phase refrigerant outlet.

[0511] The first inlet-side on-off valve 22c is an on-off valve that opens and closes the inlet-side passage 21d. More specifically, the first inlet-side on-off valve 22c opens and closes the refrigerant passage in the inlet-side passage 21d that extends from the other outlet of the second three-way joint 12b to one inlet of the seventh three-way joint 12g. The first inlet-side on-off valve 22c is a refrigerant circuit switching unit.

[0512] One of the outlets of the second three-way joint 12b is connected to one of the inlet sides of the ninth three-way joint 12i. A second inlet-side on-off valve 22d is disposed in the refrigerant passage extending from one of the outlets of the second three-way joint 12b to one of the inlet sides of the ninth three-way joint 12i. The second inlet-side on-off valve 22d opens and closes the refrigerant passage extending from one of the outlets of the second three-way joint 12b to one of the inlet sides of the eighth three-way joint 12h. The second inlet-side on-off valve 22d is a refrigerant circuit switching unit.

[0513] The basic configurations of the first inlet side on-off valve 22c and the second inlet side on-off valve 22d are similar to that of the high pressure side on-off valve 22a described in the first embodiment.

[0514] The other inlet side of the ninth three-way joint 12i is connected to the liquid-phase refrigerant outlet of the receiver 24. The refrigerant passage extending from the outlet of the receiver 24 to the other inlet side of the ninth three-way joint 12i is an outlet-side passage 21e. A tenth three-way joint 12j and a fourth check valve 16d are disposed in the outlet-side passage 21e.

[0515] The fourth check valve 16d allows refrigerant to flow from the tenth three-way joint 12j side to the ninth three-way joint 12i side, but prohibits refrigerant from flowing from the ninth three-way joint 12i side to the tenth three-way joint 12j side. The other outlet of the tenth three-way joint 12j is connected to the inlet side of the fifth three-way joint 12e. The rest of the configuration of the vehicle air conditioner 1a is similar to that of the vehicle air conditioner 1 described in the first embodiment.

[0516] Next, the operation of the vehicle air conditioner 1a of this embodiment configured as described above will be described. In the vehicle air conditioner 1a of this embodiment, various operating modes can be switched as in the first embodiment to condition the air in the vehicle compartment and regulate the temperature of the battery 70. The operation of each operating mode will be described in detail below.

[0517] (1) Cooling-alone mode In the heat pump cycle 10a in the cooling-alone mode, the control device 60 determines the control signals to be output to the heating expansion valve 14a in a fully open state, the cooling expansion valve 14b in a throttled state, the cooling expansion valve 14c in a fully closed state, and the bypass-side flow control valve 14d in a fully closed state.

[0518] The control device 60 also determines the control voltages to be output to the low-pressure side on-off valve 22b, the first inlet side on-off valve 22c, and the second inlet side on-off valve 22d so as to close them, close them, and open them, respectively.

[0519] In addition, the control device 60 determines the operating state of the cooling expansion valve 14b so that the superheat degree SH of the refrigerant sucked into the compressor 11 approaches a predetermined reference superheat degree KSH (5°C in this embodiment).

[0520] Furthermore, the control device 60 appropriately determines the operating states of other control-target devices, as in the first embodiment, and outputs control signals or control voltages to the various control-target devices so that the determined control states are obtained.

[0521] Therefore, in the heat pump cycle 10a in the cooling-only mode, the refrigerant discharged from the compressor 11 is switched to a refrigerant circuit in which it circulates in the following order: the water-refrigerant heat exchanger 13, the heating expansion valve 14a which is in a fully open state, the outdoor heat exchanger 15, the receiver 24, the cooling expansion valve 14b, the indoor evaporator 18, and the intake port of the compressor 11.

[0522] Therefore, in the heat pump cycle 10a in the single cooling mode, a vapor compression refrigeration cycle is configured in which the water-refrigerant heat exchanger 13 and the outdoor heat exchanger 15 function as condensers and the indoor evaporator 18 functions as an evaporator.

[0523] In the high-temperature side heat medium circuit 40 in the sole cooling mode, the high-temperature side heat medium heated in the water-refrigerant heat exchanger 13 flows into the heater core 42, as in the first embodiment. In the interior air-conditioning unit 30 in the sole cooling mode, temperature-adjusted air is blown into the vehicle compartment, as in the first embodiment. This achieves cooling of the vehicle compartment.

[0524] (2) Serial Dehumidifying and Heating Mode In the heat pump cycle 10a in the serial dehumidifying and heating mode, the control device 60 determines the control signals to be output to the heating expansion valve 14a in a throttled state, the cooling expansion valve 14b in a throttled state, the cooling expansion valve 14c in a fully closed state, and the bypass side flow control valve 14d in a fully closed state.

[0525] The control device 60 also determines the control voltages to be output to the low-pressure side on-off valve 22b, the first inlet side on-off valve 22c, and the second inlet side on-off valve 22d so as to close them, close them, and open them, respectively.

[0526] The control device 60 also determines the operating states of the heating expansion valve 14a and the cooling expansion valve 14b so that the degree of superheat SH of the refrigerant drawn into the compressor 11 approaches a predetermined reference degree of superheat KSH.

[0527] Furthermore, the control device 60 appropriately determines the operating states of other control-target devices, as in the first embodiment, and outputs control signals or control voltages to the various control-target devices so that the determined control states are obtained.

[0528] Therefore, in the heat pump cycle 10a in the serial dehumidifying and heating mode, the refrigerant discharged from the compressor 11 is switched to a refrigerant circuit in which it circulates in the following order: the water-refrigerant heat exchanger 13, the heating expansion valve 14a, the outdoor heat exchanger 15, the receiver 24, the cooling expansion valve 14b, the indoor evaporator 18, and the intake port of the compressor 11.

[0529] Therefore, in the heat pump cycle 10a in the serial dehumidifying heating mode, a vapor compression refrigeration cycle is configured in which the water-refrigerant heat exchanger 13 and the outdoor heat exchanger 15 function as condensers and the indoor evaporator 18 functions as an evaporator.

[0530] Furthermore, the high-temperature side heat medium circuit 40 and the indoor air conditioning unit 30 in the series dehumidifying and heating mode operate in the same manner as in the single cooling mode of the first embodiment.

[0531] In the high-temperature side heat medium circuit 40 in the series dehumidifying and heating mode, the high-temperature side heat medium heated in the water-refrigerant heat exchanger 13 flows into the heater core 42, as in the first embodiment. In the interior air-conditioning unit 30 in the series dehumidifying and heating mode, dehumidified and temperature-adjusted air is blown into the vehicle cabin, as in the first embodiment. This achieves dehumidifying and heating the vehicle cabin.

[0532] Here, the heat pump cycle 10a has a receiver 24. Therefore, the series dehumidifying heating mode is performed in a temperature range in which the saturation temperature of the refrigerant in the outdoor heat exchanger 15 is higher than the outdoor air temperature Tam.

[0533] (3-1) HG Dehumidifying and Heating Mode In the heat pump cycle 10a in the HG dehumidifying and heating mode, the control device 60 determines the control signals to be output to the heating expansion valve 14a in a fully closed state, the cooling expansion valve 14b in a throttled state, the cooling expansion valve 14c in a throttled state, and the bypass side flow control valve 14d in a throttled state.

[0534] The control device 60 also determines the control voltages to be output to the low-pressure side on-off valve 22b so as to close the low-pressure side on-off valve 22b, open the first inlet side on-off valve 22c, and close the second inlet side on-off valve 22d.

[0535] In addition, the control device 60 determines the operating states of the compressor 11, the air conditioning expansion valve 14b, the cooling expansion valve 14c, and the bypass side flow control valve 14d so that the superheat degree SH of the refrigerant sucked into the compressor 11 approaches a predetermined reference superheat degree KSH.

[0536] Furthermore, the control device 60 appropriately determines the operating states of other control-target devices, as in the first embodiment, and outputs control signals or control voltages to the various control-target devices so that the determined control states are obtained.

[0537] 34, in the heat pump cycle 10a in the HG dehumidifying and heating mode, the refrigerant discharged from the compressor 11 circulates in the following order: the first three-way joint 12a, the water-refrigerant heat exchanger 13, the inlet passage 21d, the receiver 24, the fifth three-way joint 12e, the cooling expansion valve 14b, the indoor evaporator 18, the sixth three-way joint 12f, the seventh three-way joint 12g, and the suction port of the compressor 11. Furthermore, the refrigerant discharged from the compressor 11 circulates in the following order: the first three-way joint 12a, the water-refrigerant heat exchanger 13, the inlet passage 21d, the receiver 24, the fifth three-way joint 12e, the cooling expansion valve 14c, the chiller 20, the sixth three-way joint 12f, the seventh three-way joint 12g, 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 it circulates in the following order: the first three-way joint 12a, the bypass side flow control valve 14d arranged in the bypass passage 21c, the seventh three-way joint 12g, and the intake port of the compressor 11.

[0538] Therefore, in the heat pump cycle 10a in the HG dehumidifying heating mode, the high-temperature side heat medium is heated in the water-refrigerant heat exchanger 13, as in the first embodiment.

[0539] In the high-temperature side heat medium circuit 40 in the HG dehumidifying heating mode, the high-temperature side heat medium heated in the water-refrigerant heat exchanger 13 flows into the heater core 42, similar to the first embodiment.

[0540] In the low-temperature side heat medium circuit 50 in the HG dehumidifying heating mode, heat exchange between the refrigerant and the low-temperature side heat medium does not occur in the chiller 20, as in the first embodiment.

[0541] Furthermore, in the HG dehumidifying and heating mode, the interior air conditioning unit 30 blows temperature-adjusted conditioned air into the vehicle compartment, as in the first embodiment, thereby achieving heating of the vehicle compartment.

[0542] In the HG dehumidifying and heating mode, as in the first embodiment, the heating capacity of the heater for the blown air can be improved more than in the serial dehumidifying and heating mode.

[0543] (3-2) Outdoor Air Heat Absorption HG Dehumidifying Heating Mode In the heat pump cycle 10a in the outdoor air heat absorption HG dehumidifying heating mode, the control device 60 determines the control signals to be output to the heating expansion valve 14a, the cooling expansion valve 14b, the cooling expansion valve 14c, and the bypass side flow control valve 14d so that the valves are in a throttled state, a throttled state, a throttled state, and a throttled state, respectively.

[0544] The control device 60 also determines the control voltages to be output to the low-pressure side on-off valve 22b, the first inlet side on-off valve 22c, and the second inlet side on-off valve 22d so as to open them, open them, and close them, respectively.

[0545] In addition, the control device 60 determines the operating states of the compressor 11, the heating expansion valve 14a, the cooling expansion valve 14b, and the cooling expansion valve 14c so that the superheat degree SH of the refrigerant sucked into the compressor 11 approaches a predetermined reference superheat degree KSH.

[0546] Furthermore, the control device 60 appropriately determines the operating states of other control-target devices, as in the first embodiment, and outputs control signals or control voltages to the various control-target devices so that the determined control states are obtained.

[0547] Therefore, in the heat pump cycle 10a in the outdoor air heat absorption HG dehumidifying heating mode, the refrigerant discharged from the compressor 11 flows in the same manner as in the HG dehumidifying heating mode, as shown by the solid arrows in Fig. 35. Furthermore, the refrigerant discharged from the compressor 11 is switched to a refrigerant circuit in which it circulates through the first three-way joint 12a, the water-refrigerant heat exchanger 13, the inlet passage 21d, the receiver 24, the outlet passage 21e, the heating expansion valve 14a, the outdoor heat exchanger 15, the low-pressure passage 21b, the eighth three-way joint 12h, and the suction port of the compressor 11, in this order.

[0548] Therefore, in the heat pump cycle 10a in the outdoor air heat absorption HG dehumidifying heating mode, the high-temperature side heat medium is heated in the water-refrigerant heat exchanger 13, as in the first embodiment. The blown air is cooled in the indoor evaporator 18. The refrigerant absorbs heat from the outdoor air in the outdoor heat exchanger 15.

[0549] In the high-temperature side heat medium circuit 40 in the outside air heat absorption HG dehumidifying and heating mode, the high-temperature side heat medium heated in the water-refrigerant heat exchanger 13 flows into the heater core 42, as in the first embodiment.

[0550] In the low-temperature side heat medium circuit 50 in the outside air heat absorption HG dehumidifying and heating mode, heat exchange between the refrigerant and the low-temperature side heat medium does not occur in the chiller 20, as in the first embodiment.

[0551] Furthermore, in the interior air-conditioning unit 30 in the outside air heat absorption HG dehumidifying heating mode, temperature-adjusted conditioned air is blown into the vehicle compartment, as in the first embodiment, thereby realizing heating of the vehicle compartment.

[0552] In the outdoor air heat absorption HG dehumidifying heating mode, the heating capacity of the blown air in the heating section can be improved compared to the series dehumidifying heating mode, as in the first embodiment. Furthermore, in the outdoor air heat absorption HG dehumidifying heating mode, the operating efficiency of the heat pump cycle 10a can be improved compared to the HG dehumidifying heating mode, as in the first embodiment.

[0553] (4-1) Outdoor Air Heating Mode In the heat pump cycle 10a in the outdoor air heat absorption heating mode, the control device 60 determines the control signals to be output to 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 control valve 14d in a fully closed state.

[0554] The control device 60 also determines the control voltages to be output to the low-pressure side on-off valve 22b, the first inlet side on-off valve 22c, and the second inlet side on-off valve 22d so as to open them, open them, and close them, respectively.

[0555] The control device 60 also determines the operating state of the heating expansion valve 14a so that the degree of superheat SH of the refrigerant sucked into the compressor 11 approaches a predetermined reference degree of superheat KSH.

[0556] Furthermore, the control device 60 appropriately determines the operating states of other control-target devices, as in the first embodiment, and outputs control signals or control voltages to the various control-target devices so that the determined control states are obtained.

[0557] Therefore, in the heat pump cycle 10a in the outdoor air heat absorption heating mode, the refrigerant discharged from the compressor 11 is switched to a refrigerant circuit in which it circulates in the following order: the water-refrigerant heat exchanger 13, the inlet side passage 21d, the receiver 24, the outlet side passage 21e, the heating expansion valve 14a, the outdoor heat exchanger 15, the low-pressure side passage 21b, and the suction port of the compressor 11.

[0558] Therefore, in the heat pump cycle 10a in the outdoor air heat absorption heating mode, a vapor compression refrigeration cycle is configured in which the water-refrigerant heat exchanger 13 functions as a condenser and the outdoor heat exchanger 15 functions as an evaporator.

[0559] In the high-temperature side heat medium circuit 40 in the outside air heat absorption heating mode, the high-temperature side heat medium heated in the water-refrigerant heat exchanger 13 flows into the heater core 42, as in the first embodiment. In the interior air-conditioning unit 30 in the outside air heat absorption heating mode, temperature-adjusted conditioned air is blown into the vehicle compartment, as in the first embodiment. This achieves heating of the vehicle compartment.

[0560] (4-2) HG Heating Mode In the heat pump cycle 10a in the outdoor air heat absorption heating mode, the control device 60 determines the control signals to be output to the heating expansion valve 14a in a fully closed state, the cooling expansion valve 14b in a fully closed state, the cooling expansion valve 14c in a throttled state, and the bypass side flow control valve 14d in a throttled state.

[0561] The control device 60 also determines the control voltages to be output to the low-pressure side on-off valve 22b so as to close the low-pressure side on-off valve 22b, open the first inlet side on-off valve 22c, and close the second inlet side on-off valve 22d.

[0562] In addition, the control device 60 determines the operating states of the compressor 11, the cooling expansion valve 14c, and the bypass side flow control valve 14d so that the superheat degree SH of the refrigerant sucked into the compressor 11 approaches a predetermined reference superheat degree KSH.

[0563] Furthermore, the control device 60 appropriately determines the operating states of other control-target devices, as in the first embodiment, and outputs control signals or control voltages to the various control-target devices so that the determined control states are obtained.

[0564] 36, the refrigerant discharged from the compressor 11 circulates in the following order: the first three-way joint 12a, the water-refrigerant heat exchanger 13, the inlet-side passage 21d, the receiver 24, the cooling expansion valve 14c, the chiller 20, the seventh three-way joint 12g, 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 following order: the first three-way joint 12a, the bypass-side flow control valve 14d disposed in the bypass passage 21c, the seventh three-way joint 12g, and the suction port of the compressor 11.

[0565] Therefore, in the heat pump cycle 10a in the HG dehumidifying and heating mode, the high-temperature side heat medium is heated in the water-refrigerant heat exchanger 13, as in the first embodiment.

[0566] In the high-temperature side heat medium circuit 40 in the HG heating mode, the high-temperature side heat medium heated in the water-refrigerant heat exchanger 13 flows into the heater core 42, similar to the first embodiment.

[0567] In the low-temperature side heat medium circuit 50 in the HG heating mode, heat exchange between the refrigerant and the low-temperature side heat medium does not occur in the chiller 20, as in the first embodiment.

[0568] Furthermore, in the HG heating mode, the interior air conditioning unit 30 blows temperature-adjusted conditioned air into the vehicle compartment, as in the first embodiment, thereby achieving heating of the vehicle compartment.

[0569] In the HG heating mode, similarly to the first embodiment, the heating capacity of the heater for the blown air can be improved more than in the outside air heat absorption heating mode.

[0570] (5) Cooling / Cooling Mode In the heat pump cycle 10a in the cooling / cooling mode, the control device 60 determines the control signals to be output to the heating expansion valve 14a in a fully open state, the cooling expansion valve 14b in a throttled state, the cooling expansion valve 14c in a throttled state, and the bypass side flow control valve 14d in a fully closed state.

[0571] The control device 60 also determines the control voltages to be output to the low-pressure side on-off valve 22b, the first inlet side on-off valve 22c, and the second inlet side on-off valve 22d so as to close them, close them, and open them, respectively.

[0572] The control device 60 also determines the operating states of the cooling expansion valve 14b and the cooling expansion valve 14c so that the degree of superheat SH of the refrigerant drawn into the compressor 11 approaches a predetermined reference degree of superheat KSH.

[0573] Furthermore, the control device 60 appropriately determines the operating states of other control-target devices, as in the first embodiment, and outputs control signals or control voltages to the various control-target devices so that the determined control states are obtained.

[0574] Therefore, in the heat pump cycle 10a in the cooling / cooling mode, the refrigerant discharged from the compressor 11 circulates in the following order: water-refrigerant heat exchanger 13, the fully open heating expansion valve 14a, the outdoor heat exchanger 15, the receiver 24, the fifth three-way joint 12e, the cooling expansion valve 14b, the indoor evaporator 18, 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 discharged from the compressor 11 circulates in the following order: water-refrigerant heat exchanger 13, the fully open heating expansion valve 14a, the outdoor heat exchanger 15, the receiver 24, the fifth three-way joint 12e, the cooling expansion valve 14c, the chiller 20, and the suction port of the compressor 11.

[0575] That is, the flow of refrigerant flowing out from the receiver 24 is switched to a refrigerant circuit in which the indoor evaporator 18 and the chiller 20 are connected in parallel.

[0576] Therefore, in the heat pump cycle 10a in the cooling / air-conditioning mode, a vapor compression refrigeration cycle is configured in which the water-refrigerant heat exchanger 13 and the outdoor heat exchanger 15 function as condensers, and the indoor evaporator 18 and chiller 20 function as evaporators.

[0577] In the high-temperature side heat medium circuit 40 in the cooling / air-cooling mode, the high-temperature side heat medium heated in the water-refrigerant heat exchanger 13 flows into the heater core 42, as in the first embodiment.

[0578] In the low-temperature side heat medium circuit 50 in the cooling / air-cooling mode, the low-temperature side heat medium flows through the coolant passage 70a of the battery 70, as in the first embodiment. This cools the battery 70.

[0579] Furthermore, in the cooling / air-cooling mode, the interior air-conditioning unit 30 blows temperature-adjusted conditioned air into the vehicle compartment, as in the first embodiment, thereby achieving heating of the vehicle compartment.

[0580] (6) Cooling-Serial Dehumidifying-Heating Mode In the heat pump cycle 10a in the cooling-serial dehumidifying-heating mode, the control device 60 determines the control signals to be output to the heating expansion valve 14a, the cooling expansion valve 14b, the cooling expansion valve 14c, and the bypass-side flow control valve 14d so that the valves are in a throttled state, a throttled state, a throttled state, and a fully closed state, respectively.

[0581] The control device 60 also determines the control voltages to be output to the low-pressure side on-off valve 22b, the first inlet side on-off valve 22c, and the second inlet side on-off valve 22d so as to close them, close them, and open them, respectively.

[0582] In addition, the control device 60 determines the operating states of the heating expansion valve 14a, the cooling expansion valve 14b, and the cooling expansion valve 14c so that the superheat degree SH of the refrigerant sucked into the compressor 11 approaches a predetermined reference superheat degree KSH.

[0583] Furthermore, the control device 60 appropriately determines the operating states of other control-target devices, as in the first embodiment, and outputs control signals or control voltages to the various control-target devices so that the determined control states are obtained.

[0584] Therefore, in the heat pump cycle 10a in the cooling-serial dehumidifying-heating mode, the refrigerant discharged from the compressor 11 circulates in the following order: water-refrigerant heat exchanger 13, heating expansion valve 14a, outdoor heat exchanger 15, receiver 24, fifth three-way joint 12e, cooling expansion valve 14b, indoor evaporator 18, and the suction port of the compressor 11. At the same time, the system is switched to a refrigerant circuit in which the refrigerant discharged from the compressor 11 circulates in the following order: water-refrigerant heat exchanger 13, heating expansion valve 14a, outdoor heat exchanger 15, receiver 24, fifth three-way joint 12e, cooling expansion valve 14c, chiller 20, and the suction port of the compressor 11.

[0585] That is, the flow of refrigerant flowing out from the receiver 24 is switched to a refrigerant circuit in which the indoor evaporator 18 and the chiller 20 are connected in parallel.

[0586] Therefore, in the heat pump cycle 10a in the cooling series dehumidifying heating mode, a vapor compression refrigeration cycle is configured in which the water-refrigerant heat exchanger 13 and the outdoor heat exchanger 15 function as condensers, and the indoor evaporator 18 and chiller 20 function as evaporators.

[0587] In the high-temperature side heat medium circuit 40 in the cooling serial dehumidifying and heating mode, the high-temperature side heat medium heated in the water-refrigerant heat exchanger 13 flows into the heater core 42, as in the first embodiment.

[0588] In the low-temperature side heat medium circuit 50 in the cooling series dehumidifying and heating mode, the low-temperature side heat medium flows through the coolant passage 70a of the battery 70, as in the first embodiment. This cools the battery 70.

[0589] In addition, in the interior air conditioning unit 30 in the cooling serial dehumidifying and heating mode, dehumidified and temperature-adjusted air is blown into the vehicle compartment, as in the first embodiment, thereby realizing dehumidifying and heating the vehicle compartment.

[0590] Here, the heat pump cycle 10a has a receiver 24. Therefore, similar to the series dehumidifying and heating mode, the cooling series dehumidifying and heating mode is performed in a temperature range in which the saturation temperature of the refrigerant in the outdoor heat exchanger 15 is higher than the outdoor air temperature Tam.

[0591] (7-1) Cooling HG Dehumidifying Heating Mode In the heat pump cycle 10a in the cooling HG dehumidifying heating mode, the control device 60 determines the control signals to be output to the heating expansion valve 14a in a fully closed state, the cooling expansion valve 14b in a throttled state, the cooling expansion valve 14c in a throttled state, and the bypass side flow control valve 14d in a throttled state.

[0592] The control device 60 also determines the control voltages to be output to the low-pressure side on-off valve 22b so as to close the low-pressure side on-off valve 22b, open the first inlet side on-off valve 22c, and close the second inlet side on-off valve 22d.

[0593] In addition, the control device 60 determines the operating states of the compressor 11, the air conditioning expansion valve 14b, the cooling expansion valve 14c, and the bypass side flow control valve 14d so that the superheat degree SH of the refrigerant sucked into the compressor 11 approaches a predetermined reference superheat degree KSH.

[0594] Furthermore, the control device 60 appropriately determines the operating states of other control-target devices, as in the first embodiment, and outputs control signals or control voltages to the various control-target devices so that the determined control states are obtained.

[0595] Therefore, in the heat pump cycle 10a in the cooling HG dehumidifying heating mode, as shown by the solid arrow in Figure 34, the refrigerant discharged from the compressor 11 is switched to a refrigerant circuit in which it circulates in the same order as in the HG dehumidifying heating mode.

[0596] Therefore, in the heat pump cycle 10a in the cooling HG dehumidifying heating mode, the high-temperature side heat medium is heated in the water-refrigerant heat exchanger 13, the blown air is cooled in the indoor evaporator 18, and the low-temperature side heat medium is cooled in the chiller 20, as in the first embodiment.

[0597] In the high-temperature side heat medium circuit 40 in the cooling HG dehumidifying heating mode, the high-temperature side heat medium heated in the water-refrigerant heat exchanger 13 flows into the heater core 42, similar to the first embodiment.

[0598] In the low-temperature side heat medium circuit 50 in the cooling HG dehumidifying heating mode, the low-temperature side heat medium flows through the coolant passage 70a of the battery 70, as shown by the dashed arrows in Figure 34, similar to the first embodiment. This cools the battery 70.

[0599] Furthermore, in the cooling HG dehumidifying and heating mode, the interior air conditioning unit 30 blows dehumidified and temperature-adjusted conditioned air into the vehicle compartment, as in the first embodiment, thereby realizing dehumidifying and heating the vehicle compartment.

[0600] In the cooling HG dehumidifying and heating mode, as in the first embodiment, the heating capacity of the heater for the blown air can be improved more than in the cooling serial dehumidifying and heating mode.

[0601] (7-2) Cooled Outdoor Air Heat Absorption HG Dehumidifying Heating Mode In the heat pump cycle 10a in the cooled outdoor air heat absorption HG dehumidifying heating mode, the control device 60 determines the control signals to be output to the heating expansion valve 14a, the cooling expansion valve 14b, the cooling expansion valve 14c, and the bypass side flow control valve 14d so as to be in a throttled state, a throttled state, a throttled state, and a throttled state, respectively.

[0602] The control device 60 also determines the control voltages to be output to the low-pressure side on-off valve 22b, the first inlet side on-off valve 22c, and the second inlet side on-off valve 22d so as to open them, open them, and close them, respectively.

[0603] In addition, the control device 60 determines the operating states of the compressor 11, the heating expansion valve 14a, the cooling expansion valve 14b, and the cooling expansion valve 14c so that the superheat degree SH of the refrigerant sucked into the compressor 11 approaches a predetermined reference superheat degree KSH.

[0604] Furthermore, the control device 60 appropriately determines the operating states of other control-target devices, as in the first embodiment, and outputs control signals or control voltages to the various control-target devices so that the determined control states are obtained.

[0605] Therefore, in the heat pump cycle 10a in the cooled outdoor air heat absorption HG dehumidification heating mode, as shown by the solid arrow in Figure 35, the refrigerant discharged from the compressor 11 is switched to a refrigerant circuit that circulates in the same order as in the outdoor air heat absorption HG dehumidification heating mode.

[0606] Therefore, in the heat pump cycle 10a in the cooled outdoor air heat absorption HG dehumidifying and heating mode, the high-temperature side heat medium is heated in the water-refrigerant heat exchanger 13, as in the first embodiment. The blown air is cooled in the indoor evaporator 18. The low-temperature side heat medium is cooled in the chiller 20. The refrigerant absorbs heat from the outdoor air in the outdoor heat exchanger 15.

[0607] In the cooled outside air heat absorption HG dehumidifying and heating mode, the high temperature side heat medium circuit 40 receives the high temperature side heat medium heated in the water-refrigerant heat exchanger 13 and flows into the heater core 42, as in the first embodiment.

[0608] In the low-temperature side heat medium circuit 50 in the cooled outside air heat absorption HG dehumidifying and heating mode, the low-temperature side heat medium flows through the coolant passage 70a of the battery 70, as shown by the dashed arrows in Figure 35, similar to the first embodiment. This cools the battery 70.

[0609] Furthermore, in the cooled outside air heat absorption HG dehumidifying and heating mode, the interior air conditioning unit 30 blows dehumidified and temperature-adjusted conditioned air into the vehicle cabin, as in the first embodiment, thereby realizing dehumidifying and heating the vehicle cabin.

[0610] In the cooled outdoor air heat absorption HG heating mode, the heating capacity of the blown air in the heating section can be improved compared to the cooled series dehumidifying heating mode, as in the first embodiment. Furthermore, in the cooled outdoor air heat absorption HG heating mode, the operating efficiency of the heat pump cycle 10a can be improved compared to the cooled series dehumidifying heating mode, as in the first embodiment.

[0611] (8) Refrigeration Equipment Heat Endoscopy Heating Mode In the heat pump cycle 10a in the refrigeration equipment heat endoscopy heating mode, the control device 60 determines the control signals to be output to the heating expansion valve 14a in a fully open state, the cooling expansion valve 14b in a fully closed state, the cooling expansion valve 14c in a throttled state, and the bypass side flow control valve 14d in a fully closed state.

[0612] The control device 60 also determines the control voltages to be output to the low-pressure side on-off valve 22b, the first inlet side on-off valve 22c, and the second inlet side on-off valve 22d so as to close them, close them, and open them, respectively.

[0613] The control device 60 also determines the operating state of the cooling expansion valve 14c so that the degree of superheat SH of the refrigerant drawn into the compressor 11 approaches a predetermined reference degree of superheat KSH.

[0614] Furthermore, the control device 60 appropriately determines the operating states of other control-target devices, as in the first embodiment, and outputs control signals or control voltages to the various control-target devices so that the determined control states are obtained.

[0615] Therefore, in the heat pump cycle 10a in the cooling equipment heat absorption heating mode, the refrigerant discharged from the compressor 11 is switched to a refrigerant circuit in which it circulates in the following order: the water-refrigerant heat exchanger 13, the fully open heating expansion valve 14a, the outdoor heat exchanger 15, the receiver 24, the cooling expansion valve 14c, the chiller 20, and the intake port of the compressor 11.

[0616] Therefore, in the heat pump cycle 10a in the cooling equipment heat absorption heating mode, as in the first embodiment, the high-temperature side heat medium is heated in the water-refrigerant heat exchanger 13. In addition, the refrigerant dissipates heat to the outside air in the outdoor heat exchanger 15. In addition, the low-temperature side heat medium is cooled in the chiller 20.

[0617] In the high-temperature side heat medium circuit 40 in the cooling equipment heat absorption heating mode, the high-temperature side heat medium heated in the water-refrigerant heat exchanger 13 flows into the heater core 42, similar to the first embodiment.

[0618] In the low-temperature side heat medium circuit 50 in the cooling equipment heat absorption heating mode, the low-temperature side heat medium flows through the coolant passage 70a of the battery 70, as in the first embodiment. This cools the battery 70.

[0619] Furthermore, in the cooling device heat absorption heating mode, the interior air conditioning unit 30 blows temperature-adjusted conditioned air into the vehicle compartment, as in the first embodiment, thereby achieving heating of the vehicle compartment.

[0620] (9) Cooled Outdoor Air Heat Absorption Heating Mode In the heat pump cycle 10a in the cooled outdoor air heat absorption heating mode, the control device 60 determines the control signals to be output to 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 throttled state, and the bypass side flow control valve 14d in a fully closed state.

[0621] The control device 60 also determines the control voltages to be output to the low-pressure side on-off valve 22b, the first inlet side on-off valve 22c, and the second inlet side on-off valve 22d so as to close them, close them, and open them, respectively.

[0622] The control device 60 also determines the operating states of the heating expansion valve 14a and the cooling expansion valve 14c so that the degree of superheat SH of the refrigerant drawn into the compressor 11 approaches a predetermined reference degree of superheat KSH.

[0623] Furthermore, the control device 60 appropriately determines the operating states of other control-target devices, as in the first embodiment, and outputs control signals or control voltages to the various control-target devices so that the determined control states are obtained.

[0624] Therefore, in the heat pump cycle 10a in the cooled outdoor air heat absorption heating mode, the refrigerant discharged from the compressor 11 is switched to a refrigerant circuit in which it circulates in the following order: the water-refrigerant heat exchanger 13, the heating expansion valve 14a, the outdoor heat exchanger 15, the receiver 24, the cooling expansion valve 14c, the chiller 20, and the intake port of the compressor 11.

[0625] Therefore, in the heat pump cycle 10a in the cooled outdoor air heat absorption heating mode, the high-temperature side heat medium is heated in the water-refrigerant heat exchanger 13, and the refrigerant dissipates heat to the outdoor air in the outdoor heat exchanger 15. The low-temperature side heat medium is cooled in the chiller 20, just like in the first embodiment.

[0626] In the high-temperature side heat medium circuit 40 in the cooled outside air heat absorption heating mode, the high-temperature side heat medium heated in the water-refrigerant heat exchanger 13 flows into the heater core 42, similar to the first embodiment.

[0627] In the low-temperature side heat medium circuit 50 in the cooled outside air heat absorption heating mode, the low-temperature side heat medium flows through the coolant passage 70a of the battery 70, as in the first embodiment. This cools the battery 70.

[0628] Furthermore, in the cooled outside air heat absorption heating mode, the interior air conditioning unit 30 blows temperature-adjusted conditioned air into the vehicle compartment, as in the first embodiment, thereby achieving heating of the vehicle compartment.

[0629] Here, the heat pump cycle 10a has a receiver 24. Therefore, the cooling equipment heat absorption heating mode is executed in a temperature range in which the saturation temperature of the refrigerant in the outdoor heat exchanger 15 is higher than the outdoor air temperature Tam, similar to the series dehumidifying heating mode.

[0630] (10-1) Cooling HG Heating Mode In the heat pump cycle 10a in the cooling HG heating mode, the control device 60 determines the control signals to be output to the heating expansion valve 14a in a fully closed state, the cooling expansion valve 14b in a fully closed state, the cooling expansion valve 14c in a throttled state, and the bypass side flow control valve 14d in a throttled state.

[0631] The control device 60 also determines the control voltages to be output to the low-pressure side on-off valve 22b so as to close the low-pressure side on-off valve 22b, open the first inlet side on-off valve 22c, and close the second inlet side on-off valve 22d.

[0632] In addition, the control device 60 determines the operating states of the compressor 11, the cooling expansion valve 14c, and the bypass side flow control valve 14d so that the superheat degree SH of the refrigerant sucked into the compressor 11 approaches a predetermined reference superheat degree KSH.

[0633] Furthermore, the control device 60 appropriately determines the operating states of other control-target devices, as in the first embodiment, and outputs control signals or control voltages to the various control-target devices so that the determined control states are obtained.

[0634] Therefore, in the heat pump cycle 10a in the cooling HG heating mode, as shown by the solid arrow in Figure 36, the refrigerant discharged from the compressor 11 is switched to a refrigerant circuit in which it circulates in the same order as in the HG heating mode.

[0635] Therefore, in the heat pump cycle 10a in the cooling HG heating mode, the high-temperature side heat medium is heated in the water-refrigerant heat exchanger 13, as in the first embodiment.

[0636] In the high-temperature side heat medium circuit 40 in the cooling HG heating mode, the high-temperature side heat medium heated in the water-refrigerant heat exchanger 13 flows into the heater core 42, similar to the first embodiment.

[0637] In the low-temperature side heat medium circuit 50 in the cooling HG heating mode, as shown by the dashed arrows in Figure 36, the low-temperature side heat medium flows through the coolant passage 70a of the battery 70, as in the first embodiment. This cools the battery 70.

[0638] Furthermore, in the cooling HG heating mode, the interior air conditioning unit 30 blows temperature-adjusted conditioned air into the vehicle compartment, as in the first embodiment, thereby achieving heating of the vehicle compartment.

[0639] In the HG heating mode, similarly to the first embodiment, the battery 70 is cooled, and at the same time, the heating capacity of the heater for the blown air can be improved more than in the cooled outside air heat absorption heating mode.

[0640] (10-2) Cooled outdoor air heat absorption HG heating mode In the heat pump cycle 10a in the cooled outdoor air heat absorption HG heating mode, the control device 60 determines the control signals to be output to 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 throttled state, and the bypass side flow control valve 14d in a throttled state.

[0641] The control device 60 also determines the control voltages to be output to the low-pressure side on-off valve 22b, the first inlet side on-off valve 22c, and the second inlet side on-off valve 22d so as to open the low-pressure side on-off valve 22b, open the first inlet side on-off valve 22c, and close the second inlet side on-off valve 22d, respectively.

[0642] In addition, the control device 60 determines the operating states of the compressor 11, the heating expansion valve 14a, the cooling expansion valve 14c, and the bypass side flow control valve 14d so that the superheat degree SH of the refrigerant sucked into the compressor 11 approaches a predetermined reference superheat degree KSH.

[0643] Furthermore, the control device 60 appropriately determines the operating states of other control-target devices, as in the first embodiment, and outputs control signals or control voltages to the various control-target devices so that the determined control states are obtained.

[0644] Therefore, in the heat pump cycle 10a in the cooled outdoor air heat absorption HG heating mode, the refrigerant discharged from the compressor 11 flows in the same manner as in the cooled HG heating mode, as shown by the solid arrows in Fig. 37. At the same time, the refrigerant discharged from the compressor 11 is switched to a refrigerant circuit in which it circulates through the first three-way joint 12a, the water-refrigerant heat exchanger 13, the inlet passage 21d, the receiver 24, the outlet passage 21e, the heating expansion valve 14a, the outdoor heat exchanger 15, the low-pressure passage 21b, the eighth three-way joint 12h, and the suction port of the compressor 11, in this order.

[0645] Therefore, in the heat pump cycle 10a in the cooled outdoor air heat absorption HG heating mode, the high-temperature side heat medium is heated in the water-refrigerant heat exchanger 13, as in the first embodiment. The low-temperature side heat medium is cooled in the chiller 20. The refrigerant absorbs heat from the outdoor air in the outdoor heat exchanger 15.

[0646] In the cooled outside air heat absorption HG heating mode, in the high temperature side heat medium circuit 40, the high temperature side heat medium heated in the water-refrigerant heat exchanger 13 flows into the heater core 42, as in the first embodiment.

[0647] In the cooled outside air heat absorption HG heating mode, in the low-temperature side heat medium circuit 50, as shown by the dashed arrows in Figure 37, the low-temperature side heat medium flows through the coolant passage 70a of the battery 70, as in the first embodiment. This cools the battery 70.

[0648] Furthermore, in the cooled outside air heat absorption HG heating mode, the interior air conditioning unit 30 blows temperature-adjusted conditioned air into the vehicle compartment, as in the first embodiment, thereby achieving heating of the vehicle compartment.

[0649] In the cooled outdoor air heat absorption HG heating mode, similar to the cooled outdoor air heat absorption HG heating mode, the battery 70 is cooled, and at the same time, the heating capacity of the blown air in the heating section can be improved more than in the cooled outdoor air heat absorption heating mode.

[0650] Furthermore, in the cooled outdoor air heat absorption HG heating mode, the blown air can be heated using heat absorbed from the outdoor air by the refrigerant in the outdoor heat exchanger 15. Therefore, in the cooled outdoor air heat absorption HG heating mode, the operating efficiency of the heat pump cycle 10 can be improved more than in the cooled outdoor air heat absorption HG heating mode.

[0651] (11) Cooling Mode In the heat pump cycle 10a in the cooling mode, the control device 60 determines the control signals to be output to the heating expansion valve 14a in a fully open state, the cooling expansion valve 14b in a fully closed state, the cooling expansion valve 14c in a throttled state, and the bypass side flow control valve 14d in a fully closed state.

[0652] The control device 60 also determines the control voltages to be output to the low-pressure side on-off valve 22b, the first inlet side on-off valve 22c, and the second inlet side on-off valve 22d so as to close them, close them, and open them, respectively.

[0653] The control device 60 also determines the operating state of the cooling expansion valve 14c so that the degree of superheat SH of the refrigerant drawn into the compressor 11 approaches a predetermined reference degree of superheat KSH.

[0654] Furthermore, the control device 60 appropriately determines the operating states of other control-target devices, as in the first embodiment, and outputs control signals or control voltages to the various control-target devices so that the determined control states are obtained.

[0655] Therefore, in the heat pump cycle 10a in cooling mode, the refrigerant discharged from the compressor 11 is switched to a refrigerant circuit in which it circulates in the following order: the water-refrigerant heat exchanger 13, the fully open heating expansion valve 14a, the outdoor heat exchanger 15, the receiver 24, the cooling expansion valve 14c, the chiller 20, and the intake port of the compressor 11.

[0656] Therefore, in the heat pump cycle 10a in the cooling mode, similarly to the first embodiment, the heat of the refrigerant is dissipated to the outside air in the outdoor heat exchanger 15. Also, the low-temperature side heat medium is cooled in the chiller 20.

[0657] In the low-temperature side heat medium circuit 50 in the cooling mode, the low-temperature side heat medium flows through the coolant passage 70a of the battery 70, as in the first embodiment. This cools the battery 70.

[0658] (12) Fan Mode In the fan mode, the control device 60 stops the compressor 11. The control device 60 also operates the indoor fan 32 in response to a setting signal set by the air volume setting switch.

[0659] In the indoor air conditioning unit 30 in the blowing mode, the air blown from the indoor blower 32 is blown into the room.

[0660] As described above, the vehicle air conditioner 1a of this embodiment can switch between various operation modes to appropriately adjust the temperature of the battery 70 while achieving comfortable air conditioning in the vehicle cabin.

[0661] Furthermore, the vehicle air conditioner 1a of this embodiment can achieve the same effects as the vehicle air conditioner 1 of the first embodiment. That is, when performing dehumidifying and heating of the vehicle cabin, by switching between the serial dehumidifying and heating mode and the HG dehumidifying and heating mode, the temperature of the blown air can be continuously adjusted over a wide range while suppressing a decrease in operating efficiency.

[0662] In addition, when dehumidifying and heating the vehicle interior, by switching between the cooling series dehumidifying and heating mode and the cooling HG dehumidifying and heating mode, the battery 70 can be cooled while simultaneously suppressing a decrease in operating efficiency and continuously adjusting the temperature of the blown air over a wide range.

[0663] Furthermore, when heating the vehicle interior, by switching between the outside air heat absorption heating mode and the HG heating mode, the temperature of the blown air can be continuously adjusted over a wide range while suppressing a decrease in operating efficiency.

[0664] In addition, when heating the vehicle interior, by switching between the cooled outside air heat absorption heating mode and the cooled HG heating mode, the battery 70 can be cooled while simultaneously suppressing a decrease in operating efficiency and continuously adjusting the temperature of the blown air over a wide range.

[0665] The present disclosure is not limited to the above-described embodiments, and various modifications can be made as follows within the scope of the present disclosure.

[0666] In the above-described embodiment, an example has been described in which the refrigeration cycle device according to the present disclosure is applied to the vehicle air conditioner 1, 1a, but the application of the refrigeration cycle device according to the present disclosure is not limited to vehicle use. For example, the refrigeration cycle device may be applied to a stationary air conditioner with a temperature adjustment function that adjusts the temperature of an object to be cooled (e.g., a computer, a server device, or other peripheral devices) while air conditioning the interior of the vehicle.

[0667] In the above embodiment, the refrigeration cycle device according to the present disclosure is applied to an air conditioner with an in-vehicle equipment temperature adjustment function, and an example is described in which the temperature of the battery 70 is adjusted as the in-vehicle equipment. However, the in-vehicle equipment is not limited to the battery 70. For example, the temperature of an inverter, a PCU, a transaxle, a control device for an ADAS, etc. may be adjusted. Furthermore, the temperature of multiple in-vehicle equipment may be adjusted.

[0668] The inverter supplies power to the motor generator, etc. The PCU is a power control unit that transforms electricity and distributes power. The transaxle is a power transmission mechanism that integrates the transmission, differential gear, etc. The ADAS control device is a control device for the advanced driver assistance system.

[0669] Of course, the refrigeration cycle device according to the present disclosure may be applied to an air conditioning device that does not have the function of adjusting the temperature of an object to be cooled, such as an in-vehicle device, and that exclusively conditions the air of a space to be air-conditioned.

[0670] The configuration of the refrigeration cycle device according to the present disclosure is not limited to the configuration disclosed in the above-described embodiment.

[0671] In the above embodiment, an example has been described in which the heating unit is formed by the water-refrigerant heat exchanger 13 and the components of the high-temperature side heat medium circuit 40, but the heating unit is not limited to this.

[0672] For example, an interior condenser may be used as the heating unit. The interior condenser is a heat exchange unit for heating the blown air by exchanging heat between one of the refrigerant discharged from the first three-way joint 12a and the blown air that has passed through the interior evaporator 18. The interior condenser may be disposed in the air passage of the interior air conditioning unit 30 in the same manner as the heater core 42.

[0673] In the above embodiment, an example has been described in which the cooling unit is formed by the chiller 20 and the components of the low-temperature side heat medium circuit 50, but the cooling unit is not limited to this.

[0674] For example, a thermosiphon may be used as the cooling unit, in which the chiller 20 of the low-temperature side heat medium circuit 50 functions as a condenser and the cooling water passage 70a functions as an evaporator. This makes it possible to eliminate the low-temperature side pump 51.

[0675] A thermosiphon is a heat transport circuit that has an evaporator section that evaporates a refrigerant and a condenser section that condenses the refrigerant, and is configured by connecting the evaporator section and the condenser section in a closed loop (i.e., annular shape). The temperature difference between the refrigerant in the evaporator section and the condenser section creates a difference in specific gravity of the refrigerant in the circuit, and the refrigerant is naturally circulated by gravity, transporting heat along with the refrigerant.

[0676] For example, the cooling unit may employ a cooling heat exchange unit that directly exchanges heat between the low-pressure refrigerant of the heat pump cycle and the battery 70 without using a low-temperature side heat medium, and causes the low-pressure refrigerant to directly absorb waste heat from the battery 70. For example, the cooling unit may employ an air-cooled cooling device that blows blown air cooled by a cooling evaporator onto the battery 70.

[0677] In addition, in the above-described embodiment, an example was described in which the seventh three-way joint 12g and the eighth three-way joint 12h, which are the confluence parts, are positioned downstream of the refrigerant flow in the sixth embodiment 12f, but the positioning of the confluence parts is not limited to this.

[0678] For example, the seventh three-way joint 12g may be arranged in a refrigerant passage extending from the outlet side of the cooling expansion valve 14c to the refrigerant inlet side of the chiller 20. For example, the seventh three-way joint 12g may be arranged in a refrigerant passage extending from the refrigerant outlet side of the chiller 20 to the inlet side of the refrigerant expansion valve 12f in the sixth embodiment. For example, in the heat pump cycle 10 of the first embodiment, the seventh three-way joint 12g may be eliminated and the bypass passage 21c may be directly connected to the accumulator 23.

[0679] Furthermore, in the above-described embodiment, an example was described in which a confluence was formed using the seventh three-way joint 12g and the eighth three-way joint 12h, but the confluence may also be formed using a four-way joint that integrates the seventh three-way joint 12g and the eighth three-way joint 12h.

[0680] Similarly, in the heat pump cycle device 10 of the first embodiment, the fourth three-way joint 12d and the fifth three-way joint 12e may be integrated into a four-way joint. In the heat pump cycle device 10a of the second embodiment, the ninth three-way joint 12i and the fifth three-way joint 12e may be integrated into a four-way joint.

[0681] Furthermore, in the heat pump cycle 10a of the second embodiment, a subcooling expansion valve may be disposed in the refrigerant passage extending from the outlet side of the fourth three-way joint 12d to the inlet side of the receiver 24. The subcooling expansion valve reduces the pressure of the refrigerant flowing into the receiver 24. A fixed throttle or a variable throttle mechanism may be used as the subcooling expansion valve.

[0682] This increases the degree of subcooling of the refrigerant flowing out of the water-refrigerant heat exchanger 13, thereby increasing the refrigerant pressure (i.e., discharge refrigerant pressure Pd) in the water-refrigerant heat exchanger 13. As a result, the heating capacity of the high-temperature side heat medium in the water-refrigerant heat exchanger 13 is improved, thereby improving the heating capacity of the blown air.

[0683] In the above-described embodiment, the refrigerant used in the heat pump cycle 10, 10a is R1234yf, but this is not limiting. For example, R134a, R600a, R410A, R404A, R32, R407C, etc. may be used. Alternatively, a mixed refrigerant containing a mixture of two or more of these refrigerants may be used. Furthermore, carbon dioxide may be used as the refrigerant to configure a supercritical refrigeration cycle in which the high-pressure side refrigerant pressure is equal to or higher than the critical pressure of the refrigerant.

[0684] In the above embodiment, the refrigeration oil is PAG oil (i.e., polyalkylene glycol oil), but the present invention is not limited to this. For example, POE (i.e., polyol ester) or the like may be used.

[0685] In the above embodiment, an example was described in which an ethylene glycol aqueous solution was used as the heat medium, low-temperature heat medium, and high-temperature heat medium, but this is not limiting. For example, a solution containing dimethylpolysiloxane or nanofluid, antifreeze, an aqueous liquid refrigerant containing alcohol, or a liquid medium containing oil may also be used.

[0686] Furthermore, the group of control sensors connected to the input side of the control device 60 is not limited to the detection units disclosed in the above embodiment. Various detection units may be added as needed.

[0687] In the above-described embodiment, the vehicle air conditioners 1, 1a are described as being capable of switching between a plurality of operation modes, but the switching of operation modes is not limited to this.

[0688] If it is possible to switch at least between (2) serial dehumidifying heating mode and (3-1) HG dehumidifying heating mode, the temperature of the blown air can be continuously adjusted over a wide range while suppressing a decrease in operating efficiency when dehumidifying and heating the air-conditioned space.

[0689] If it is possible to switch between at least (6) cooling serial dehumidifying heating mode and (7-1) cooling HG dehumidifying heating mode, when dehumidifying and heating the air-conditioned space, it is possible to cool the battery 70 while simultaneously suppressing a decrease in operating efficiency and continuously adjust the temperature of the blown air over a wide range.

[0690] If it is possible to switch between at least (4-1) outdoor air heat absorption heating mode and (4-2) HG heating mode, the temperature of the blown air can be continuously adjusted over a wide range while suppressing a decrease in operating efficiency when heating the air-conditioned space.

[0691] If it is possible to switch at least between (9) cooled outdoor air heat absorption heating mode and (10-1) cooled HG heating mode, when heating the air-conditioned space, it is possible to cool the battery 70 while simultaneously suppressing a decrease in operating efficiency and continuously adjust the temperature of the blown air over a wide range.

[0692] In the above embodiment, as described in step S140, etc., an example was described in which the outdoor unit temperature difference ΔTO and the blowing temperature difference ΔTAO are used to determine whether the refrigerant in the outdoor heat exchanger 15 can properly absorb the heat of the outside air, but this is not limited to this.

[0693] For example, to determine whether heat absorption by outside air is possible, the amount of heat absorption by the refrigerant when it flows into the outdoor heat exchanger 15 may be predicted, and it may be determined whether the amount of heat absorption is excessive for the target blow-out temperature TAO. For example, to determine whether heat absorption by outside air is possible, the flow rate (mass flow rate) of the refrigerant flowing through the outdoor heat exchanger 15 when the refrigerant flows into the outdoor heat exchanger 15 may be predicted, and it may be determined whether refrigeration oil can be returned to the compressor 11.

[0694] The means disclosed in each of the above embodiments may be combined as appropriate within a practicable range. For example, the control aspect relating to the switching of the operation mode described in the second embodiment may be applied to the vehicle air conditioner 1a described in the third embodiment.

[0695] The refrigeration cycle device disclosed in this specification has the following features. (Item 1) A compressor (11) that compresses and discharges a refrigerant, an upstream branch section (12a) that branches the flow of the refrigerant discharged from the compressor, a heating section (13, 40) that heats blown air to be blown into a space to be air-conditioned using the refrigerant flowing out from one outlet of the upstream branch section as a heat source, a heating section side decompression section (14a, 14b, 14c) that decompresses the refrigerant flowing out from the heating section, an outdoor heat exchange section (15) that exchanges heat between the refrigerant flowing out from the heating section side decompression section and outside air, an indoor evaporation section (18) that evaporates the refrigerant decompressed in the heating section side decompression section to cool the blown air before being heated in the heating section, a bypass passage (21c) that guides the other refrigerant branched at the upstream branch section to a suction port side of the compressor, and a bypass side flow rate adjustment section (14d) that adjusts the flow rate of the refrigerant flowing through the bypass passage. a merging section (12g, 12h) that merges the flow of the refrigerant flowing out from the heating section side decompression section and the flow of the refrigerant flowing out from the bypass side flow rate adjustment section, and causes the refrigerant to flow out to the intake port side of the compressor; and a refrigerant circuit switching section (22a, 22b, 22c, 22d) that switches a refrigerant circuit, wherein the heating section side decompression section has an outdoor side decompression section (14a) that decompresses the refrigerant flowing into the outdoor heat exchange section, an indoor side decompression section (14b) that decompresses the refrigerant flowing into the indoor evaporator section, and a bypass side decompression section (14c) that decompresses the refrigerant that flows bypassing the outdoor heat exchange section and the indoor evaporator section, and has a series dehumidifying heating mode and a hot gas dehumidifying heating mode as operation modes in which the blown air cooled in the indoor evaporator section is reheated in the heating section, and the refrigerant circuit switching section In the serial dehumidifying and heating mode, the refrigerant discharged from the compressor is switched to a refrigerant circuit in which it circulates through the heating unit, the outdoor pressure reducing unit, the outdoor heat exchange unit, the indoor pressure reducing unit, the indoor evaporator unit, and the compressor suction port in this order,In the hot gas dehumidifying and heating mode, the refrigerant discharged from the compressor circulates in the order of the upstream branch section, the heating section, the indoor pressure reduction section, the indoor evaporation section, the junction section, and the compressor suction port, and further, the refrigerant discharged from the compressor circulates in the order of the upstream branch section, the heating section, the bypass pressure reduction section, the junction section, and the compressor suction port, and the refrigerant discharged from the compressor is switched to a refrigerant circuit in which the refrigerant circulates in the order of the upstream branch section, the heating section, the bypass pressure reduction section, the junction section, and the compressor suction port. (Item 2) The refrigeration cycle apparatus according to item 1, further comprising: a target discharge temperature determination unit (S20) that determines a target discharge temperature (TAO) of the blown air to be blown into the air-conditioned space; and a blown air temperature detection unit (66) that detects a blown air temperature (TAV) of the blown air to be blown into the air-conditioned space, wherein the refrigerant circuit switching unit switches from the series dehumidifying heating mode to the hot gas dehumidifying heating mode when the blown air temperature (TAV) is lower than the target discharge temperature (TAO). (Item 3) The refrigeration cycle apparatus according to item 1 or 2, further comprising: a target evaporator temperature determination unit (S1907) that determines a target evaporator temperature (TEO) of the indoor evaporator; and an evaporator temperature detection unit (62f) that detects an evaporator temperature (Tefin) of the indoor evaporator, wherein the refrigerant circuit switching unit switches from the hot gas dehumidifying and heating mode to the series dehumidifying and heating mode when the evaporator temperature (Tefin) is higher than the target evaporator temperature (TEO). (Item 4) The refrigeration cycle apparatus further comprises an outside air heat absorption hot gas dehumidifying and heating mode as an operation mode in which the blown air cooled by the indoor evaporator is reheated by the heating unit, and the refrigerant circuit switching unit4. The refrigeration cycle apparatus according to any one of items 1 to 3, wherein in the outdoor air heat absorption hot gas dehumidifying and heating mode, the refrigerant discharged from the compressor circulates in the order of the upstream branch section, the heating section, the outdoor side pressure reduction section, the outdoor heat exchange section, the junction section, and the compressor suction port, and the refrigerant discharged from the compressor circulates in the order of the upstream branch section, the heating section, the indoor side pressure reduction section, the indoor evaporator section, the junction section, and the compressor suction port, and further, the refrigerant discharged from the compressor circulates in the order of the upstream branch section, the heating section, the bypass side pressure reduction section, the junction section, and the compressor suction port, and the refrigerant discharged from the compressor circulates in the order of the upstream branch section, the heating section, the bypass side pressure reduction section, the junction section, and the compressor suction port, and the refrigerant discharged from the compressor circulates in the order of the upstream branch section, the bypass passage, the junction section, and the compressor suction port. (Item 5) The refrigeration cycle apparatus according to item 4, further comprising: a target evaporator temperature determination unit (S1907) that determines a target evaporator temperature (TEO) of the indoor evaporator; and an outdoor air temperature detection unit (61b) that detects an outdoor air temperature (Tam) that is the temperature of the outdoor air, wherein the refrigerant circuit switching unit switches from the hot gas dehumidifying heating mode to the outdoor air heat absorption hot gas dehumidifying heating mode when an outdoor evaporator temperature difference (ΔTO) obtained by subtracting the target evaporator temperature (TEO) from the outdoor air temperature (Tam) becomes equal to or greater than a predetermined reference temperature difference (KΔTO1). (Item 6) The refrigeration cycle apparatus according to item 4 or 5, further comprising: a target evaporator temperature determination unit (S1807) that determines a target evaporator temperature (TEO) of the indoor evaporator; and an evaporator temperature detection unit (62f) that detects the evaporator temperature (Tefin) of the indoor evaporator, wherein the refrigerant circuit switching unit switches from the outdoor air heat absorption hot gas dehumidifying heating mode to the hot gas dehumidifying heating mode when the evaporator temperature (Tefin) is higher than the target evaporator temperature (TEO). (Item 7) The refrigeration cycle apparatus according to item 4 or 5, further comprising: a cooling unit (20, 50) that cools an object to be cooled, wherein the cooling unit cools the object to be cooled, and the heating unit reheats the blown air cooled by the indoor evaporator, and the cooling unit has a cooling series dehumidifying heating mode and a cooling hot gas dehumidifying heating mode as operation modes,In the cooling series dehumidifying and heating mode, the refrigerant discharged from the compressor circulates in the order of the heating unit, the outdoor side pressure reduction unit, the outdoor heat exchange unit, the indoor side pressure reduction unit, the indoor evaporator unit, and the suction port of the compressor, and the refrigerant discharged from the compressor is switched to a refrigerant circuit in which the refrigerant circulates in the order of the heating unit, the outdoor side pressure reduction unit, the outdoor heat exchange unit, the bypass side pressure reduction unit, the cooling unit, and the suction port of the compressor, 7. The refrigeration cycle apparatus according to any one of items 1 to 6, wherein in the cooled hot gas dehumidifying and heating mode, the refrigerant discharged from the compressor circulates in the order of the upstream branch section, the heating section, the indoor side pressure reduction section, the indoor evaporation section, the junction section, and the compressor suction port, and further switches to a refrigerant circuit in which the refrigerant discharged from the compressor circulates in the order of the upstream branch section, the heating section, the bypass side pressure reduction section, the cooling section, the junction section, and the compressor suction port, and the refrigerant discharged from the compressor circulates in the order of the upstream branch section, the bypass passage, the junction section, and the compressor suction port. (Item 8) A compressor (11) that compresses and discharges a refrigerant, an upstream branch section (12a) that branches the flow of the refrigerant discharged from the compressor, a heating section (13, 40) that heats air to be blown into a space to be air-conditioned using the refrigerant flowing out from one outlet of the upstream branch section as a heat source, a heating section side decompression section (14a, 14b, 14c) that decompresses the refrigerant flowing out from the heating section, an outdoor heat exchange section (15) that exchanges heat between the refrigerant flowing out from the heating section side decompression section and outside air, a bypass passage (21c) that guides the other refrigerant branched at the upstream branch section to the suction port side of the compressor, and a bypass side flow rate adjustment section (14d) that adjusts the flow rate of the refrigerant flowing through the bypass passage. a confluence section (12g, 12h) that merges the flow of the refrigerant flowing out from the heating section side decompression section and the flow of the refrigerant flowing out from the bypass side flow rate adjustment section, and causes the refrigerant to flow out to the intake port side of the compressor, and a refrigerant circuit switching section (22a, 22b, 22c, 22d) that switches a refrigerant circuit, wherein the heating section side decompression section has an outdoor side decompression section (14a) that decompresses the refrigerant flowing into the outdoor heat exchange section, and a bypass side decompression section (14c) that decompresses the refrigerant that flows bypassing the outdoor heat exchange section,a refrigeration cycle apparatus having an outdoor air heat absorption heating mode and a hot gas heating mode as operation modes in which the blown air is heated by the heating section, and wherein the refrigerant circuit switching section switches to a refrigerant circuit in which the refrigerant discharged from the compressor circulates in the order of the heating section, the outdoor side pressure reduction section, the outdoor heat exchange section, and the compressor suction port in the outdoor air heat absorption heating mode, and switches to a refrigerant circuit in which the refrigerant discharged from the compressor circulates in the order of the upstream side branch section, the heating section, the bypass side pressure reduction section, the junction, and the compressor suction port in the hot gas heating mode, and switches to a refrigerant circuit in which the refrigerant discharged from the compressor circulates in the order of the upstream side branch section, the heating section, the bypass side pressure reduction section, the junction, and the compressor suction port in the hot gas heating mode. (Item 9) The refrigeration cycle apparatus according to item 8, comprising: a target discharge temperature determination unit (S20) that determines a target discharge temperature (TAO) of the blown air to the air-conditioned space; and a blown air temperature detection unit (66) that detects a blown air temperature (TAV) of the blown air to the air-conditioned space, wherein the refrigerant circuit switching unit switches from the outdoor air endothermic heating mode to the hot gas heating mode when the blown air temperature (TAV) is lower than the target discharge temperature (TAO). (Item 10) The refrigeration cycle apparatus according to item 8 or 9, comprising: a target discharge temperature determination unit (S20) that determines a target discharge temperature (TAO) of the blown air to the air-conditioned space, wherein the refrigerant circuit switching unit switches from the hot gas heating mode to the outdoor air endothermic heating mode when the target discharge temperature (TAO) is lower than a hot gas reference temperature (δ). (Item 11) A cooling unit (20, 50) is provided for cooling an object to be cooled, and the cooling unit cools the object to be cooled while the heating unit heats the blown air, and the cooling unit has a cooling series dehumidifying heating mode and a cooling hot gas dehumidifying heating mode as operation modes, the bypass side decompression unit decompresses the refrigerant flowing into the cooling unit, and the cooling unit cools the object to be cooled while the heating unit heats the blown air, and the cooling unit has a cooling outside air heat absorption heating mode and a cooling hot gas heating mode as operation modes, and the refrigerant circuit switching unit11. The refrigeration cycle apparatus according to any one of items 8 to 10, wherein in the cooled outdoor air heat absorption heating mode, the refrigerant discharged from the compressor is switched to a refrigerant circuit in which it circulates through the heating section, the outdoor side pressure reduction section, the outdoor heat exchange section, the bypass side pressure reduction section, the cooling section, and the compressor suction port in that order; and in the cooled hot gas heating mode, the refrigerant discharged from the compressor is switched to a refrigerant circuit in which it circulates through the upstream side branch section, the heating section, the bypass side pressure reduction section, the cooling section, the junction, and the compressor suction port in that order, and the refrigerant discharged from the compressor is switched to a refrigerant circuit in which it circulates through the upstream side branch section, the bypass passage, the junction, and the compressor suction port in that order.

[0696] Although the present disclosure has been described with reference to the embodiments, it is understood that the present disclosure is not limited to the embodiments or structures. The present disclosure also encompasses various modifications and equivalent modifications. In addition, various combinations and forms, including only one element, more than one element, or less than one element, are also within the scope and spirit of the present disclosure.

Claims

1. A compressor (11) that compresses and discharges a refrigerant; an upstream branch portion (12a) that branches the flow of the refrigerant discharged from the compressor; a heating section (13, 40) that heats the air to be blown to the space to be air-conditioned using the refrigerant flowing out from one outlet of the upstream branch section as a heat source; a heating unit side decompression unit (14a, 14b, 14c) for decompressing the refrigerant flowing out from the heating unit; an outdoor heat exchange section (15) for exchanging heat between the refrigerant flowing out from the heating section side decompression section and outside air; an indoor evaporation section (18) that evaporates the refrigerant decompressed in the heating section side decompression section to cool the blown air before it is heated in the heating section; a bypass passage (21c) for guiding the other of the refrigerant branched at the upstream branch portion to the suction port side of the compressor; a bypass-side flow rate adjusting unit (14d) for adjusting a flow rate of the refrigerant flowing through the bypass passage; a confluence section (12g, 12h) that merges the flow of the refrigerant flowing out from the heating section side pressure reduction section and the flow of the refrigerant flowing out from the bypass side flow rate adjustment section, and causes the refrigerant to flow toward a suction port side of the compressor; A refrigerant circuit switching unit (22a, 22b, 22c, 22d) that switches the refrigerant circuit, The heating unit-side pressure reduction section includes an outdoor side pressure reduction section (14a) that reduces the pressure of the refrigerant flowing into the outdoor heat exchange section, an indoor side pressure reduction section (14b) that reduces the pressure of the refrigerant flowing into the indoor evaporating section, and a bypass side pressure reduction section (14c) that reduces the pressure of the refrigerant that flows bypassing the outdoor heat exchange section and the indoor evaporating section, The air conditioner has an operation mode in which the blown air cooled in the indoor evaporator is reheated in the heater, and a series dehumidification heating mode and a hot gas dehumidification heating mode are provided as operation modes in which the blown air cooled in the indoor evaporator is reheated in the heater. The refrigerant circuit switching unit is In the serial dehumidifying and heating mode, the refrigerant discharged from the compressor is switched to a refrigerant circuit in which it circulates through the heating section, the outdoor side pressure reducing section, the outdoor heat exchange section, the indoor side pressure reducing section, the indoor evaporator section, and the suction port of the compressor in this order; In the hot gas dehumidifying and heating mode, the refrigerant discharged from the compressor circulates in the order of the upstream branch section, the heating section, the indoor side pressure reduction section, the indoor evaporator section, the junction section, and the compressor suction port, and further, the refrigerant discharged from the compressor circulates in the order of the upstream branch section, the heating section, the bypass side pressure reduction section, the junction section, and the compressor suction port, and the refrigerant discharged from the compressor circulates in the order of the upstream branch section, the bypass passage, the junction section, and the compressor suction port.

2. A target blowing temperature determination unit (S20) that determines a target blowing temperature (TAO) of the blown air to be blown into the air-conditioned space; a blown air temperature detection unit (66) that detects a blown air temperature (TAV) of the blown air blown to the air-conditioned space, 2. The refrigeration cycle apparatus according to claim 1, wherein the refrigerant circuit switching unit switches from the series dehumidification heating mode to the hot gas dehumidification heating mode when the blowing air temperature (TAV) is lower than the target blowing temperature (TAO).

3. A target evaporator temperature determination unit (S1907) that determines a target evaporator temperature (TEO) of the indoor evaporator unit; an evaporator temperature detection unit (62f) that detects an evaporator temperature (Tefin) of the indoor evaporator unit; 2. The refrigeration cycle apparatus according to claim 1, wherein the refrigerant circuit switching unit switches from the hot gas dehumidification heating mode to the series dehumidification heating mode when the evaporator temperature (Tefin) is higher than the target evaporator temperature (TEO).

4. Further, an outside air heat absorbing hot gas dehumidifying and heating mode is provided as an operation mode in which the blown air cooled in the indoor evaporating section is reheated in the heating section, The refrigerant circuit switching unit is 2. The refrigeration cycle apparatus according to claim 1, wherein in the outdoor air heat absorption hot gas dehumidification heating mode, the refrigerant discharged from the compressor circulates in the order of the upstream branch section, the heating section, the outdoor side pressure reduction section, the outdoor heat exchange section, the junction section, and the compressor suction port, and the refrigerant discharged from the compressor circulates in the order of the upstream branch section, the heating section, the indoor side pressure reduction section, the indoor evaporator section, the junction section, and the compressor suction port, and further, the refrigerant discharged from the compressor circulates in the order of the upstream branch section, the heating section, the bypass side pressure reduction section, the junction section, and the compressor suction port, and the refrigerant discharged from the compressor circulates in the order of the upstream branch section, the heating section, the bypass side pressure reduction section, the junction section, and the compressor suction port, and the refrigerant discharged from the compressor circulates in the order of the upstream branch section, the bypass passage, the junction section, and the compressor suction port.

5. A target evaporator temperature determination unit (S1907) that determines a target evaporator temperature (TEO) of the indoor evaporator unit; An outside air temperature detection unit (61b) that detects an outside air temperature (Tam), The refrigeration cycle device according to claim 4, wherein the refrigerant circuit switching unit switches from the hot gas dehumidification heating mode to the outdoor air heat absorption hot gas dehumidification heating mode when an outdoor unit temperature difference (ΔTO) obtained by subtracting the target evaporator temperature (TEO) from the outdoor air temperature (Tam) becomes equal to or greater than a predetermined reference temperature difference (KΔTO1).

6. A target evaporator temperature determination unit (S1807) that determines a target evaporator temperature (TEO) of the indoor evaporator unit; an evaporator temperature detection unit (62f) that detects an evaporator temperature (Tefin) of the indoor evaporator unit; 5. The refrigeration cycle apparatus according to claim 4, wherein the refrigerant circuit switching unit switches from the outside air heat absorbing hot gas dehumidifying heating mode to the hot gas dehumidifying heating mode when the evaporator temperature (Tefin) is higher than the target evaporator temperature (TEO).

7. A cooling unit (20, 50) for cooling an object to be cooled is provided, The cooling unit cools the object to be cooled, and the heating unit reheats the blown air cooled in the indoor evaporator, as an operation mode, a cooling serial dehumidification heating mode and a cooling hot gas dehumidification heating mode are provided; The refrigerant circuit switching unit is In the cooling serial dehumidification heating mode, the refrigerant discharged from the compressor circulates in the order of the heating section, the outdoor side pressure reduction section, the outdoor heat exchange section, the indoor side pressure reduction section, the indoor evaporator section, and the suction port of the compressor, and the refrigerant discharged from the compressor is switched to a refrigerant circuit in which the refrigerant circulates in the order of the heating section, the outdoor side pressure reduction section, the outdoor heat exchange section, the bypass side pressure reduction section, the cooling section, and the suction port of the compressor, 7. The refrigeration cycle apparatus according to claim 1, wherein in the cooling hot gas dehumidification heating mode, the refrigerant discharged from the compressor circulates in the order of the upstream branch section, the heating section, the indoor side pressure reduction section, the indoor evaporator section, the junction section, and the compressor suction port, and further, the refrigerant discharged from the compressor circulates in the order of the upstream branch section, the heating section, the bypass side pressure reduction section, the cooling section, the junction section, and the compressor suction port, and the refrigerant discharged from the compressor circulates in the order of the upstream branch section, the bypass passage, the junction section, and the compressor suction port.

8. A compressor (11) that compresses and discharges a refrigerant; an upstream branch portion (12a) that branches the flow of the refrigerant discharged from the compressor; a heating section (13, 40) that heats the air to be blown to the space to be air-conditioned using the refrigerant flowing out from one outlet of the upstream branch section as a heat source; a heating unit side decompression unit (14a, 14b, 14c) for decompressing the refrigerant flowing out from the heating unit; an outdoor heat exchange section (15) for exchanging heat between the refrigerant flowing out from the heating section side decompression section and outside air; a bypass passage (21c) for guiding the other of the refrigerant branched at the upstream branch portion to the suction port side of the compressor; a bypass-side flow rate adjusting unit (14d) for adjusting a flow rate of the refrigerant flowing through the bypass passage; a confluence section (12g, 12h) that merges the flow of the refrigerant flowing out from the heating section side pressure reduction section and the flow of the refrigerant flowing out from the bypass side flow rate adjustment section, and causes the refrigerant to flow toward a suction port side of the compressor; A cooling unit (20, 50) for cooling an object to be cooled; A refrigerant circuit switching unit (22a, 22b, 22c, 22d) that switches the refrigerant circuit, The heating unit-side pressure reduction section has an outdoor side pressure reduction section (14a) that reduces the pressure of the refrigerant flowing into the outdoor heat exchange section, and a bypass side pressure reduction section (14c) that reduces the pressure of the refrigerant flowing in a bypass around the outdoor heat exchange section, The bypass-side pressure reduction section reduces the pressure of the refrigerant flowing into the cooling section, The operation mode in which the blown air is heated by the heating unit includes an outside air heat absorption heating mode and a hot gas heating mode, The cooling unit cools the object to be cooled and the heating unit heats the blown air. The cooling unit has an operation mode in which the object to be cooled is cooled by the cooling unit and an operation mode in which the blown air is heated by the heating unit are cooled in series with dehumidification and heating, and a cooling hot gas dehumidification and heating mode. Further, the cooling device has a cooling outdoor air heat absorption heating mode and a cooling hot gas heating mode as operation modes in which the object to be cooled is cooled by the cooling unit and the blown air is heated by the heating unit, The refrigerant circuit switching unit is In the outdoor air heat absorption heating mode, the refrigerant discharged from the compressor is switched to a refrigerant circuit in which it circulates through the heating section, the outdoor side decompression section, the outdoor heat exchange section, and the suction port of the compressor in this order. In the hot gas heating mode, the refrigerant discharged from the compressor circulates in the order of the upstream branch section, the heating section, the bypass side pressure reduction section, the junction section, and the suction port of the compressor, and the refrigerant discharged from the compressor is switched to a refrigerant circuit in which the refrigerant circulates in the order of the upstream branch section, the bypass passage, the junction section, and the suction port of the compressor, In the cooling outdoor air heat absorption heating mode, the refrigerant discharged from the compressor is switched to a refrigerant circuit in which it circulates through the heating section, the outdoor side pressure reduction section, the outdoor heat exchange section, the bypass side pressure reduction section, the cooling section, and the suction port of the compressor in this order. In the cooling hot gas heating mode, the refrigerant discharged from the compressor circulates in the order of the upstream branch section, the heating section, the bypass side pressure reduction section, the cooling section, the junction section, and the compressor suction port, and the refrigeration cycle device switches to a refrigerant circuit in which the refrigerant discharged from the compressor circulates in the order of the upstream branch section, the bypass passage, the junction section, and the compressor suction port.

9. A target blowing temperature determination unit (S20) that determines a target blowing temperature (TAO) of the blown air to be blown into the air-conditioned space; a blown air temperature detection unit (66) that detects a blown air temperature (TAV) of the blown air blown to the air-conditioned space, 9. The refrigeration cycle apparatus according to claim 8, wherein the refrigerant circuit switching unit switches from the outside air heat absorption heating mode to the hot gas heating mode when the blowing air temperature (TAV) is lower than the target blowing temperature (TAO).

10. A target blowing temperature determination unit (S20) that determines a target blowing temperature (TAO) of the blown air to be blown into the air-conditioned space, 9. The refrigeration cycle apparatus according to claim 8, wherein the refrigerant circuit switching unit switches from the hot gas heating mode to the outside air heat absorption heating mode when the target blowing temperature (TAO) becomes lower than a hot gas reference temperature (δ).