Vehicle air conditioning

Abstract

Vehicle air conditioning system (1), comprising: a compressor (2) for compressing a refrigerant; an air flow channel (3) through which the air to be supplied to a vehicle interior flows; a cooler (4) which allows the refrigerant to radiate heat and thus heats the air to be supplied from the air flow duct (3) into the vehicle interior; an external heat exchanger (7) arranged outside the vehicle interior, which allows the refrigerant to absorb heat; and a control unit (32), wherein the control unit (32) is designed to carry out at least one heating process to allow the refrigerant discharged from the compressor (2) to radiate heat in the cooler (4), to decompress the refrigerant from which the heat has been radiated, and then to allow the refrigerant to absorb heat in the outdoor heat exchanger (7), wherein the vehicle air conditioning system (1) comprises a heat generating device temperature adjusting device (61) for circulating a heat carrier in a heat generating device (55) mounted in a vehicle to adjust the temperature of the heat generating device (55), wherein the heat generating device temperature adjusting device (61) comprises a heating device (66) for heating the heat carrier and a refrigerant-heat carrier heat exchanger (64) for heat exchange between the refrigerant and the heat carrier, wherein the control unit (32) has a heat carrier heat absorption / heating mode for allowing the refrigerant discharged from the compressor (2) to radiate heat into the cooler (4), decompressing the refrigerant from which the heat has been radiated, and then allowing the refrigerant to absorb heat in the refrigerant-heat carrier heat exchanger (64), and wherein, when the temperature of the heat carrier is a predetermined threshold value T1 or less when switching from the heating operation to the heat carrier heat absorption / heating mode, the control device (32) is configured to heat the heat carrier by the heating device (66) to increase the temperature of the heat carrier before switching to the heat carrier heat absorption / heating mode, and then to perform the switch to the heat carrier heat absorption / heating mode.

Description

Technical area

[0001] The present invention relates to a heat pump type air conditioning system that conditions the air in the passenger compartment of a vehicle, in particular to a vehicle air conditioning system suitable for a hybrid vehicle and an electric vehicle, each of which has a heat generating device such as a battery. State of the art

[0002] Due to the current environmental problems in recent years, hybrid cars and electric vehicles, each of which drives an electric motor for operation with electricity from a battery, have become widespread. Furthermore, as an air conditioner applicable to such a vehicle, an air conditioner has been developed that includes a refrigerant cycle in which a compressor for compressing and discharging a refrigerant, a radiator arranged inside a vehicle to allow the refrigerant to radiate heat, a heat absorber arranged inside the vehicle to allow the refrigerant to absorb heat, and an outdoor heat exchanger arranged outside the vehicle interior to allow outside air to flow through and allow the refrigerant to absorb or radiate heat are connected. This system changes and performs a heating mode (a heating operation).to let the refrigerant discharged from the compressor radiate heat in the radiator and let the refrigerant from which the heat was radiated in the radiator absorb heat in the outdoor heat exchanger, and a cooling mode (a cooling operation) to let the refrigerant discharged from the compressor radiate heat in the outdoor heat exchanger and let the refrigerant absorb heat in the heat absorber (see, for example, Patent Document 1).

[0003] On the other hand, for example, the battery (heat-generating device) installed in the vehicle becomes extremely hot during charging or due to self-heating during discharging. There is a risk that charging / discharging the battery in this state will cause its deterioration to progress, and the battery will soon fail, resulting in damage. For example, a battery has been developed that is capable of regulating the temperature of a secondary battery (battery) by circulating air (heat transfer medium) cooled by a refrigerant circulating in a refrigerant circuit (see, for example, Patent Document 2). Document listPatent document Patent document 1: JP 2014 - 213 765 A Patent document 2: JP 2016 - 090 201 A

[0004] Further exemplary vehicle air conditioning systems are shown in DE 11 2018 003 766 T5 and US 2014 / 0 374 060 A1. Summary of the inventionProblems to be solved by the invention

[0005] If the possibility is created to use the heat from the heat-generating device, such as the battery, to heat the vehicle interior by allowing the refrigerant to absorb heat from the heat transfer medium, the progression of icing on the exterior heat exchanger can be delayed. Furthermore, even if icing in the exterior heat exchanger makes heat absorption from the outside air impossible, it is possible to heat the vehicle interior by absorbing heat from the heat transfer medium.

[0006] However, there is a problem that when the temperature of the heat carrier is cold, when changing from an operating state of performing heat absorption from the outside air in the outdoor heat exchanger to an operating state of performing heat absorption from the heat carrier, the heating ability is significantly reduced and the temperature of the air blown into the vehicle interior is temporarily lowered, which makes a passenger feel uncomfortable and unpleasant.

[0007] The present invention has been developed to solve such conventional technical problems and aims to provide a vehicle air conditioning system capable of eliminating inconveniences due to a reduction in heating performance when switching from heat absorption from outside air to heat absorption from a heat carrier. Means of solving the problem

[0008] A vehicle air conditioning system according to the invention is provided, comprising: a compressor for compressing a refrigerant, an air flow duct through which the air to be supplied to a vehicle interior flows, a radiator that allows the refrigerant to radiate heat and thus heat the air to be supplied from the air flow duct into the vehicle interior, an outdoor heat exchanger arranged outside the vehicle interior that allows the refrigerant to absorb heat, and a control unit. The control unit is configured to perform at least one heating operation to allow the refrigerant discharged from the compressor to radiate heat in the radiator, to decompress the refrigerant from which the heat has been radiated, and then to allow the refrigerant to absorb heat in the outdoor heat exchanger. The vehicle air conditioning system is characterized by comprising a heat generating device temperature adjusting device.to circulate a heat carrier in a heat generating device mounted in a vehicle to adjust the temperature of the heat generating device, and that the heat generating device temperature adjusting device has a heating device for heating the heat carrier and a refrigerant-heat carrier heat exchanger for heat exchange between the refrigerant and the heat carrier, and that the control device has a heat carrier heat absorption / heating mode for allowing the refrigerant discharged from the compressor to radiate heat into the radiator, decompressing the refrigerant from which the heat has been radiated, and then allowing the refrigerant to absorb heat in the refrigerant-heat carrier heat exchanger, and when the temperature of the heat carrier is a predetermined threshold value T1 or less when switching from the heating mode to the heat carrier heat absorption / heating mode, the control device is configured toto heat the heat carrier by the heating device to increase the temperature of the heat carrier before switching to the heat carrier heat absorption / heating mode, and then switching to the heat carrier heat absorption / heating mode.

[0009] The vehicle air conditioner of the invention according to claim 2 is characterized in that, in the above invention, when a predetermined prediction and judgment condition that outside air heat is not absorbable is set in the heating operation, the control device is configured to determine that there is a possibility that it will be unable to absorb heat from the outside air in the outdoor heat exchanger and judges whether the temperature of the heat medium is equal to the threshold value T1 or less, and when the temperature thereof is equal to the threshold value T1 or less, the control device is configured to start heating the heat medium by the heater and enter the heat medium heat absorption / heating mode until the temperature of the heat medium has risen to at least a temperature higher than the threshold value T1.

[0010] The vehicle air conditioner of the invention according to claim 3 is characterized in that, in the above invention, the prediction and judgment condition that outside air heat is not absorbable includes at least one of the following conditions: reducing a refrigerant suction temperature Ts of the compressor to a predetermined value Ts1 or less, increasing a frosting amount of the outdoor heat exchanger to a predetermined value Fr1 or higher, increasing a progress speed of frosting of the outdoor heat exchanger to a predetermined value X1 or higher, reducing an outside air temperature Tam to a predetermined value Tam1 or less, and increasing a decreasing speed of the outside air temperature Tam to a predetermined value Y1 or higher.

[0011] The vehicle air conditioner of the invention according to claim 4 is characterized in that in each of the above inventions, the control device is configured to determine the threshold value T1 based on at least one of a target heating capability TGQhp of the radiator, a target outlet temperature TAO which is a target value of a temperature of the air blown into the vehicle interior, a voltage BLV of an interior blower at which the air is to be passed through the air flow passage, and a target heating temperature TCO which is a target value of a temperature of the air on the leeward side of the radiator.

[0012] The vehicle air conditioner of the invention according to claim 5 is characterized in that in each of the above invention, when a predetermined judgment condition that outside air heat is absorbable is set in the execution of the heat carrier heat absorption / heating mode, the control device is arranged to determine that the absorption of heat from the outside air is possible in the outdoor heat exchanger, and to let the refrigerant from which the heat has been radiated in the radiator absorb heat in the outdoor heat exchanger and the refrigerant-heat carrier heat exchanger.

[0013] The vehicle air conditioner of the invention according to claim 6 is characterized in that, in the above invention, the judging condition that outside air heat is absorbable includes at least one of the following conditions: the refrigerant suction temperature Ts of the compressor is lower than the predetermined value Ts1 by a predetermined value Ts2 or higher, the frosting amount of the outdoor heat exchanger is larger than the predetermined value Fr1 by a predetermined value Fr2 or less, the progress speed of frosting of the outdoor heat exchanger is faster than the predetermined value X1 by a predetermined value X2 or less, the outside air temperature Tam is lower than the predetermined value Tam1 by a predetermined value Tam2 or higher, and the decreasing speed of the outside air temperature Tam is faster than the predetermined value Y1 by a predetermined value Y2 or less. Advantageous effect of the invention

[0014] According to the present invention, in a vehicle air conditioning system comprising a compressor for compressing a refrigerant, an air flow channel through which air to be supplied to a vehicle interior flows, a radiator for allowing the refrigerant to radiate heat and thereby heat the air to be supplied from the air flow channel into the vehicle interior, an outdoor heat exchanger arranged outside the vehicle interior for allowing the refrigerant to absorb heat, and a control device, wherein the control device is configured to perform at least one heating operation to allow the refrigerant discharged from the compressor to radiate heat into the radiator, to decompress the refrigerant from which the heat has been radiated, and then to allow the refrigerant to absorb heat in the outdoor heat exchanger, the vehicle air conditioning system comprises a heat generating device temperature adjusting device,to circulate a heat carrier in a vehicle-mounted heat generator to adjust the temperature of the heat carrier. The heat carrier temperature adjustment device has a heater for heating the heat carrier and a refrigerant-heat carrier heat exchanger for heat exchange between the refrigerant and the heat carrier. The control unit has a heat carrier heat absorption / heating mode to allow the refrigerant discharged from the compressor to radiate heat in the radiator, decompress the refrigerant from which the heat has been radiated, and then allow the refrigerant to absorb heat in the refrigerant-heat carrier heat exchanger. Therefore, when switching to the heat carrier heat absorption / heating mode, the heat absorption from the heat carrier of the heat carrier temperature adjustment device is carried out in such a way thatThat the heating of the vehicle interior is carried out efficiently. For example, even if the heating device is cooled properly while icing on the exterior heat exchanger is suppressed, or if icing forms in the exterior heat exchanger, making it unable to absorb heat from the outside air, heat is absorbed from the heat carrier of the heat generating device's temperature adjustment device, thereby enabling the heating of the vehicle interior.

[0015] Specifically, when the temperature of the heat medium is a predetermined threshold T1 or lower when switching from the heating operation to the heat medium heat absorption / heating mode, the control device is configured to heat the heat medium with the heater before switching to the heat medium heat absorption / heating mode to increase the temperature of the heat medium, and then switch to the heat medium heat absorption / heating mode. This makes it possible to ensure sufficient heating performance when switching from the heating operation to the heat medium heat absorption / heating mode. This also eliminates the disadvantage that the heating operation is switched to the heat medium heat absorption / heating mode in the state where the temperature of the heat medium is low, and the outlet temperature is temporarily lowered, causing a passenger to feel uncomfortable and uneasy.

[0016] Further, as in the invention of claim 2, the control device is configured to determine, when a predetermined prediction and judgment condition that outside air heat is not absorbable is established in the heating operation, that there is a possibility that it will not be able to absorb heat from the outside air in the outdoor heat exchanger, and judges whether the temperature of the heat medium is equal to or less than the threshold T1. If the temperature is below the threshold T1, the control device is configured to start heating the heat medium with the heater and to transition to the heat medium heat absorption / heating mode until the temperature of the heat medium rises to at least a temperature above the threshold T1, thus enabling a smooth transition from the heating operation to the heat medium heat absorption / heating mode.

[0017] Incidentally, in this case, as in the invention according to claim 3, the prediction and judgment condition that outside air heat is not absorbable preferably includes at least one of the following conditions: reducing the temperature Ts of the compressor to a predetermined value Ts1 or less, increasing a frosting amount of the outdoor heat exchanger to a predetermined value Fr1 or higher, increasing a progress speed of frosting of the outdoor heat exchanger to a predetermined value X1 or higher, reducing the outside air temperature Tam to a predetermined value Tam1 or less, and increasing a reduction speed of the outside air temperature Tam to a predetermined value Y1 or higher.

[0018] Furthermore, as in the invention of claim 4, the control unit is configured to determine the threshold value T1 based on at least one of the following: a target heating capacity TGQhp of the radiator, a target outlet temperature TAO, which is a target value of a temperature of the air blown into the vehicle interior, a voltage BLV of the interior blower at which the air is to be passed through the air flow duct, and a target heating temperature TCO, which is a target value of a temperature of the air on the leeward side of the radiator. Thus, the control unit is able to appropriately determine whether heating of the heat carrier by the heating device is necessary and avoid unnecessary heating by the heating device.

[0019] Furthermore, as in the invention of claim 5, when a predetermined judgment condition that outside air heat is absorbable is established during execution of the heat-transfer medium heat absorption / heating mode, the control device is configured to determine that heat absorption from the outside air is possible in the outside heat exchanger, and to allow the refrigerant from which heat was radiated in the radiator to absorb heat in the outside heat exchanger and the refrigerant-heat-transfer medium heat exchanger. Therefore, when heat absorption from the outside air is possible in the outside heat exchanger, it is possible to perform heat absorption from the outside air together with heat absorption from the heat transfer medium, thus heating the vehicle interior.

[0020] Incidentally, as in the invention of claim 6, the judging condition that outside air heat is absorbable in this case is preferably at least one of the following conditions: the refrigerant suction temperature Ts of the compressor is lower than the predetermined value Ts1 by a predetermined value Ts2 or higher, the frosting amount of the outdoor heat exchanger is larger than the predetermined value Fr1 by a predetermined value Fr2 or less, the progress speed of frosting of the outdoor heat exchanger is faster than the predetermined value X1 by a predetermined value X2 or less, the outside air temperature Tam is lower than the predetermined value Tam1 by a predetermined value Tam2 or higher, and the decreasing speed of the outside air temperature Tam is faster than the predetermined value Y1 by a predetermined value Y2 or less. Brief description of the drawings Fig. 1 is a schematic view of a vehicle air conditioner of an embodiment to which the present invention is applied; Fig. 2 is a block diagram of an electrical circuit of a regulator in the vehicle air conditioning system of Fig. 1; Fig. 3 is a diagram showing heating operation by the controller of Fig. 2 describes; Fig. 4 is a diagram showing dehumidification and heating operation by the controller of Fig. 2 describes; Fig. Figure 5 is a diagram showing an internal circuit operation by the controller of Fig. 2 describes; Fig. 6 is a diagram showing dehumidification and cooling operation by the controller of Fig. 2 describes; Fig. Figure 7 is a diagram showing a cooling operation by the controller of Fig. 2 describes; Fig. Figure 8 is a diagram showing a first heat carrier heat absorption / heating mode by the controller of Fig. 2 describes; Fig. Figure 9 is a diagram illustrating a second heat carrier heat absorption / heating mode by the controller of Fig. 2 describes; Fig. 10 is a flowchart showing the change of control from heating operation to first heat carrier heat absorption / heating mode and second heat carrier heat absorption / heating mode by the controller of Fig. 2 describes when there is a possibility that heat absorption from the outside air becomes impossible; Fig. 11 is a diagram describing a heat absorption-adaptable heat carrier temperature MAP that the controller of Fig. 2 has; Fig. 12 is a diagram describing the temperature changes of the respective parts when switching from the heating mode to the second heat carrier heat absorption / heating mode in which there is a possibility that heat absorption from the outside air becomes impossible; Fig. 13 is a pH diagram of a refrigerant circuit in which heat transfer fluid preheating is carried out; and Fig. Figure 14 is a pH diagram of the refrigerant circuit in which the heat transfer fluid preheating is not performed. Mode for carrying out the invention

[0021] In the following, embodiments of the present invention will be described in detail with reference to the drawings.

[0022] Fig. 1 shows a schematic diagram of a vehicle air conditioner 1 of one embodiment of the present invention. A vehicle of the embodiment to which the present invention is applied is an electric vehicle (EV) in which an engine (an internal combustion engine) is not installed, and which is installed with a battery 55 and runs with an electric motor for operation (not shown in the drawing) driven by the supply of power charged in the battery 55. The vehicle air conditioner 1 of this invention is also driven by the power of the battery 55.

[0023] That is, in the electric vehicle that is unable to drive the heater by engine waste heat, the vehicle air conditioner 1 of the embodiment performs a heating operation by a heat pump operation using a refrigerant cycle R. Further, the vehicle air conditioner 1 selectively performs a dehumidifying and heating operation, an internal cycle operation, a dehumidifying and cooling operation, and a cooling operation for air conditioning a vehicle interior.

[0024] Incidentally, the vehicle is not limited to electric vehicles, and the present invention is also effective for a so-called hybrid car, in which the engine is used together with the electric motor for operation. Furthermore, it goes without saying that the present invention is also applicable to an ordinary car that runs on the engine.

[0025] The vehicle air conditioning system 1 of the embodiment performs air conditioning (heating, cooling, dehumidification, and ventilation) of the vehicle interior of the electric vehicle. It includes an electric compressor 2 for compressing a refrigerant; a cooler 4 provided in an air flow duct 3 of an HVAC unit 10 in which air in the vehicle interior is ventilated and circulated; a high-temperature, high-pressure refrigerant discharged from the compressor 2 flows therein via a refrigerant line 13G and allows the refrigerant to radiate heat to the vehicle interior; an outdoor expansion valve 6 consisting of an electric valve that decompresses and expands the refrigerant during heating; an outdoor heat exchanger 7 that performs heat exchange between the refrigerant and the outside air to function as a cooler so that the refrigerant can radiate heat during cooling and to function as an evaporator.so that the refrigerant can absorb heat during heating; an indoor expansion valve 8, consisting of an electric valve (which may be a mechanical expansion valve) to decompress and expand the refrigerant; a heat absorber 9, provided in the air flow channel 3, so that the refrigerant can absorb heat during cooling and dehumidification from inside and outside the vehicle; a storage tank 12, and others are sequentially connected by a refrigerant pipe 13, thereby forming a refrigerant circuit R. The outdoor expansion valve 6 decompresses and expands the refrigerant flowing out of the radiator 4 and flowing into the outdoor heat exchanger 7, and can also be completely closed.

[0026] Incidentally, an outdoor fan 15 is provided in the outdoor heat exchanger 7. The outdoor fan 15 forcibly passes the outside air through the outdoor heat exchanger 7, thereby effecting heat exchange between the outside air and the refrigerant. The outside air continues to pass through the outdoor heat exchanger 7 even when the vehicle is stopped (i.e., its speed is 0 km / h). Furthermore, 23 in the drawing is a shutter called a grille shutter. When the shutter 23 is closed, it is designed to prevent flowing air from entering the outdoor heat exchanger 7.

[0027] Furthermore, a refrigerant line 13A connected to a refrigerant outlet side of the outdoor heat exchanger 7 is connected to a refrigerant line 13B via a check valve 18. Incidentally, the check valve 18 has a refrigerant line side 13B serving as a forward direction. The refrigerant line 13B is connected to the indoor expansion valve 8 via a solenoid valve 17 as an opening / closing valve that is opened during cooling. In the embodiment, these solenoid valves 17 and the indoor expansion valve 8 constitute a valve device for controlling the refrigerant flow into the heat absorber 9.

[0028] In addition, the refrigerant line 13A extending from the outdoor heat exchanger 7 branches, and this branched refrigerant line 13D is connected to a refrigerant line 13C located on the outlet side of the heat absorber 9 via a solenoid valve 21 opened during heating. Then, after connecting the refrigerant line 13D, the refrigerant line 13C is connected to the accumulator 12 via a check valve 40, and the accumulator 12 is connected to a refrigerant suction side of the compressor 2. Incidentally, the check valve 40 has a side facing the accumulator 12, which serves as a forward direction.

[0029] Further, a refrigerant line 13E at an outlet side of the chiller 4 branches into a refrigerant line 13J and a refrigerant line 13F before the outdoor expansion valve 6 (on a refrigerant upstream side). One branched refrigerant line 13J is connected to a refrigerant inlet side of the outdoor heat exchanger 7 via the outdoor expansion valve 6. In addition, the other branched refrigerant line 13F communicates and connects with a connecting part of the refrigerant line 13A and the refrigerant line 13B, which are located on a refrigerant downstream side of the check valve 18 and a refrigerant suction side of the solenoid valve 17, via a solenoid valve 22, which is opened during dehumidification.

[0030] Consequently, the refrigerant line 13F is connected in parallel to a series circuit of the outdoor expansion valve 6, the outdoor heat exchanger 7, and the check valve 18. The refrigerant line 13F serves as a circuit that bypasses the outdoor expansion valve 6, the outdoor heat exchanger 7, and the check valve 18. Furthermore, a solenoid valve 20 is connected in parallel to the outdoor expansion valve 6.

[0031] In addition, suction ports such as an outside air suction port and an inside air suction port are formed in the air flow channel 3 on an air flow side in front of the heat absorber 9 (in Fig. 1 by a suction port 25), and a suction changeover flap 26 is arranged in the suction port 25 to switch the air to be introduced into the air flow duct 3 between inside air, which is the air of the vehicle interior (inside air circulation), and outside air, which is the air outside the vehicle interior (outside air introduction). Furthermore, an inside fan (blower) 27 is arranged on an air flow side behind the suction changeover flap 26 to supply the introduced inside or outside air into the air flow duct 3.

[0032] In addition, an air mixing damper 28 is provided in the air flow duct 3 on an air flow side in front of the cooler 4 to adjust a ratio at which the air in the air flow duct 3 (the inside or outside air), which flows into the air flow duct 3 and is passed through the heat absorber 9, is to be passed through the cooler 4. In addition, an outlet (represented by an outlet 29 in Fig. 1) for FUß (foot), VENT (ventilation) or DEF (defroster), and an outlet changeover damper 31 is arranged in the outlet 29 to carry out the alternating control of blowing out the air from each of the above-mentioned outlets.

[0033] Furthermore, the vehicle air conditioner 1 of this invention is provided with a heat generating device temperature adjusting device 61 for circulating a heat carrier through the battery 55 to regulate the temperature of the battery 55. Incidentally, the battery 55 in the embodiment is adopted as an example of the heat generating device in the present invention, but is not limited thereto. The battery 55 may be an electric motor for driving, an inverter for controlling, or the like.

[0034] The heat generating device temperature adjustment device 61 of this embodiment is provided with a circulation pump 62 as a circulation device for circulating the heat transfer medium through the battery 55 (heat generating device), a heat transfer medium heater 66 as a heating device, and a refrigerant-heat transfer medium heat exchanger 64. These and the battery 55 are connected in a ring-like manner by a heat transfer medium pipe 68.

[0035] In the present embodiment, the heat carrier heating heater 66 is connected to a pressure side of the circulation pump 62. An inlet of a heat carrier passage 64A of the refrigerant-heat carrier heat exchanger 64 is connected to an outlet of the heat carrier heating heater 66. An inlet of the battery 55 is connected to an outlet of the heat carrier passage 64A, and an outlet of the battery 55 is connected to a suction side of the circulation pump 62.

[0036] The heat transfer medium in the temperature control device 61 of the heat generator can be water, a refrigerant such as HFO-1234f, a liquid such as a coolant or the like, or a gas such as air or the like. Incidentally, water is used as the heat transfer medium in this embodiment. The heat transfer medium heating element 66 also consists of an electric heater such as a PTC heater or the like. Furthermore, a jacket structure is provided around the battery 55, for example, which is capable of circulating the heat transfer medium in heat exchange with the battery 55.

[0037] When the circulation pump 62 is operating, the heat transfer fluid exiting the circulation pump 62 then reaches the heat transfer fluid heating element 66. When the heat transfer fluid heating element 66 generates heat, the heat transfer fluid is heated there and then flows into the heat transfer fluid passage 64A of the refrigerant-heat transfer fluid heat exchanger 64. The heat transfer fluid flowing out of the heat transfer fluid passage 64A of the refrigerant-heat transfer fluid heat exchanger 64 reaches the battery 55. There, the heat transfer fluid undergoes heat exchange with the battery 55 and is then sucked into the circulation pump 62 to be circulated in the heat transfer fluid line 68.

[0038] On the other hand, one end of a branch pipe 72 as a branch circuit, which is arranged on a refrigerant downstream side (forward side) of the check valve 18 and a refrigerant upstream side of the solenoid valve 17, is connected to an outlet of the refrigerant pipe 13F of the refrigerant circuit R, that is, a connecting part of the refrigerant pipe 13F, the refrigerant pipe 13A, and the refrigerant pipe 13B. An auxiliary expansion valve 73 composed of an electric valve is provided in the branch pipe 72. The auxiliary expansion valve 73 is capable of decompressing and expanding the refrigerant flowing into a refrigerant passage 64B of the refrigerant-heat-transfer medium heat exchanger 64, which will be described later, and also fully closing it. Then, the other end of the branch pipe 72 is connected to the refrigerant passage 64B of the refrigerant-heat-transfer medium heat exchanger 64.One end of a refrigerant line 74 is connected to an outlet of the refrigerant passage 64B, and the other end of the refrigerant line 74 is connected to the refrigerant line 13C upstream of the accumulator 12 (a refrigerant side upstream of the accumulator 12 and a refrigerant side downstream of the check valve 40). Note that these, the auxiliary expansion valve 73, and others also constitute part of the refrigerant circuit R and, at the same time, even constitute part of the heat generator temperature adjusting device 61.

[0039] When the auxiliary expansion valve 73 is opened, the refrigerant (part or all of the refrigerant) flowing out of the refrigerant line 13F and the outdoor heat exchanger 7 is expanded in the auxiliary expansion valve 73 and then flows into the refrigerant passage 64B of the refrigerant-heat-transfer medium heat exchanger 64 to evaporate. As the refrigerant flows through the refrigerant passage 64B, it absorbs heat from the heat transfer medium flowing through the heat transfer medium passage 64A and is then drawn into the compressor 2 through the accumulator 12.

[0040] Next is Fig. 2, Fig. 32 is a controller (ECU) as a control unit. The controller 32 consists of a microcomputer, which is an example of a computer with a processor, and an input of the controller is connected to the corresponding outputs of an outside air temperature sensor 33 that detects the outside air temperature (Tam) of the vehicle, an outside air humidity sensor 34 that detects the outside air humidity, an HVAC intake temperature sensor 36 that detects a temperature of the air to be sucked in from the intake opening 25 to the air flow duct 3, an indoor air temperature sensor 37 that detects a temperature of the air in the vehicle interior (the room air), a room air humidity sensor 38 that detects a humidity of the air in the vehicle interior, an indoor air CO2 concentration sensor 39 that detects a carbon dioxide concentration in the vehicle interior, and an outlet temperature sensor 41 that detects a temperature of the air to be discharged from the outlet 29 into the vehicle interior.a discharge pressure sensor 42 that detects a pressure (a discharge pressure Pd) of the refrigerant discharged from the compressor 2, a discharge temperature sensor 43 that detects a temperature of the refrigerant discharged from the compressor 2, a suction temperature sensor 44 that detects a temperature Ts of the refrigerant to be sucked into the compressor 2, a radiator temperature sensor 46 that detects a temperature of the radiator 4 (the temperature of the refrigerant immediately after the refrigerant flows out of the radiator 4: a radiator temperature TCI in the embodiment), a radiator pressure sensor 47 that detects a refrigerant pressure of the radiator 4 (the pressure of the refrigerant in the radiator 4 or immediately after the refrigerant flows out of the radiator 4: a radiator pressure PCI), a heat absorber temperature sensor 48,which detects a temperature of the heat absorber 9 (the temperature of the air passed through the heat absorber 9 or the temperature of the heat absorber 9 itself: a heat absorber temperature Te), a heat absorber pressure sensor 49 which detects a refrigerant pressure of the heat absorber 9 (the pressure of the refrigerant in the heat absorber 9 or immediately after the refrigerant flows out of the heat absorber 9), a solar radiation sensor 51 of, for example, a photosensor system for detecting an amount of solar radiation into the vehicle interior, a speed sensor 52 for detecting a moving speed (a speed) of the vehicle, an (aircon) air conditioning control part 53 for setting the change of a predetermined temperature or an air conditioning operation, an outdoor heat exchanger temperature sensor 54,which measures a temperature of the outdoor heat exchanger 7 (the temperature of the refrigerant immediately after the refrigerant flows out of the outdoor heat exchanger 7 or the temperature of the outdoor heat exchanger 7 itself: an outdoor heat exchanger temperature TXO. When the outdoor heat exchanger 7 functions as an evaporator, the outdoor heat exchanger temperature TXO becomes an evaporation temperature of the refrigerant in the outdoor heat exchanger 7), and an outdoor heat exchanger pressure sensor 56 that measures a refrigerant pressure of the outdoor heat exchanger 7 (the pressure of the refrigerant in the outdoor heat exchanger 7 or immediately after the refrigerant flows out of the outdoor heat exchanger 7: an outdoor heat exchanger pressure PXO, which becomes an evaporation pressure of the refrigerant in the outdoor heat exchanger 7).

[0041] Furthermore, the input of the controller 32 is also connected to corresponding outputs of a battery temperature sensor 76 which detects a temperature of the battery 55 (a temperature of the battery 55 itself, or a temperature of the heating medium flowing out of the battery 55, or a temperature of the heat carrier flowing into the battery 55), a heat carrier warm-up heater temperature sensor 77 which detects a temperature of the heat carrier warm-up heater 66 (a temperature of the heat carrier warm-up heater 66 itself), a heat carrier temperature sensor 80 which detects a temperature of the heat carrier flowing out of the heat carrier warm-up heater 66 (a heat carrier temperature Tw), a first outlet temperature sensor 78 which detects a temperature of the heat carrier flowing out of the heat carrier passage 64A of the refrigerant-heat carrier heat exchanger 64, and a second outlet temperature sensor 79 which detects a temperature of the heat carrier flowing out of the refrigerant passage 64B. refrigerant is recorded.

[0042] On the other hand, an output of the controller 32 is connected to the compressor 2, the outdoor blower 15, the indoor blower (the blower) 27, the suction changeover damper 26, the air mix damper 28, the discharge changeover damper 31, the outdoor expansion valve 6, the indoor expansion valve 8, the respective solenoid valves of the solenoid valve 22 (dehumidifying), the solenoid valve 17 (cooling), the solenoid valve 21 (heating) and the solenoid valve 20 (bypass), the shutter 23, the circulation pump 62, the heat carrier warm-up heater 66 and the auxiliary expansion valve 73. The controller 32 then controls these components based on the outputs of the respective sensors and the settings input from the air conditioning control panel 53.

[0043] Next, an operation of the vehicle air conditioner 1 of the embodiment having the above-mentioned configuration will be described. In the embodiment, the controller 32 switches and executes the respective air conditioning operations of heating operation, dehumidifying and heating operation, internal circulation operation, dehumidifying and cooling operation, and cooling operation, and controls the temperature of the battery 55 within a predetermined, appropriate temperature range. Each air conditioning operation of the refrigerant circuit R will be described first. (1) Heating mode

[0044] First, the heating mode is selected based on Fig. 3 described. Fig. Figure 3 shows the flow (solid line arrows) of the refrigerant in the refrigerant circuit R in heating mode. When the heating mode is selected by controller 32 (automatic mode) or manual operation via the air conditioning control panel 53 (manual mode), controller 32 opens solenoid valve 21 (for heating) and closes solenoid valve 17 (for cooling). The controller also closes solenoid valve 22 (for dehumidification) and solenoid valve 20 (for bypass). In addition, shutter 23 is open.

[0045] Then, the controller operates the compressor 2 and the corresponding fans 15 and 27, and the air mix damper 28 has a state in which a ratio is set at which the air blown by the indoor fan 27 should pass through the radiator 4. As a result, a high-temperature, high-pressure gas refrigerant discharged from the compressor 2 flows into the radiator 4. The air in the air flow passage 3 passes through the radiator 4, and thus the air in the air flow passage 3 is heated by the high-temperature refrigerant in the radiator 4. On the other hand, the refrigerant in the radiator 4 has the heat absorbed by the air and is cooled to condense and liquefy.

[0046] The refrigerant liquefied in the cooler 4 flows out of the cooler 4 and then flows through the refrigerant lines 13E and 13J to the outdoor expansion valve 6. The refrigerant flowing into the outdoor expansion valve 6 is decompressed therein and then flows into the outdoor heat exchanger 7. The refrigerant flowing into the outdoor heat exchanger 7 evaporates, and the heat is lifted (pumped) from the outside air passed by the vehicle or by the outdoor fan 15 (heat absorption). In other words, the refrigerant circuit R functions like a heat pump.Then, the low-temperature refrigerant exiting the outdoor heat exchanger 7 flows sequentially through the refrigerant line 13A, the refrigerant line 13D, the solenoid valve 21, and the check valve 40, and flows from the refrigerant line 13C into the accumulator 12 to undergo gas-liquid separation. The gaseous refrigerant is then drawn into the compressor 2, thus repeating this cycle. The air heated in the radiator 4 is discharged from the outlet 29, thus heating the vehicle interior.

[0047] The controller 32 calculates a chiller target pressure PCO (a target pressure PCI of the chiller 4) from a target heating temperature TCO (a heating temperature TH target value to be described later, which is a temperature of the air on the leeward side of the chiller 4) calculated from a target outlet temperature TAO mentioned below, and controls the rotation speed of the compressor 2 based on the chiller target pressure PCO and the refrigerant pressure of the chiller 4 detected by the chiller pressure sensor 47 (the chiller pressure PCI, which is a high pressure of the refrigerant cycle R). Further, the controller controls a valve position of the outdoor expansion valve 6 based on the temperature (the chiller temperature TCI) of the chiller 4 detected by the chiller temperature sensor 46 and the chiller pressure PCI detected by the chiller pressure sensor 47, and controls a degree of subcooling of the refrigerant in an outlet of the chiller 4.The target heating temperature TCO is basically TCO = TAO, but a predefined control limit is provided. (2) Dehumidification and heating mode

[0048] Next, the dehumidification and heating mode is selected using Fig. 4 described. Fig. 4 shows the flow rate (solid line arrows) of the refrigerant of the refrigerant circuit R in the dehumidification and heating mode. In the dehumidification and heating mode, the controller 32 opens the solenoid valve 22 and the solenoid valve 17 in the above heating mode state. Further, the shutter 23 is opened. As a result, part of the condensed refrigerant flowing through the radiator 4 into the refrigerant line 13E is dispersed. The dispersed refrigerant flows through the solenoid valve 22 into the refrigerant line 13F and flows from the refrigerant line 13B into the indoor expansion valve 8, and the remaining refrigerant flows through the outdoor expansion valve 6. That is, the dispersed part of the refrigerant is decompressed in the indoor expansion valve 8 and then flows into the heat absorber 9 to evaporate.

[0049] The controller 32 controls a valve position of the indoor expansion valve 8 to maintain a superheat degree (SH) at an outlet of the heat absorber 9 at a predetermined value. However, the water in the air blown from the indoor fan 27 condenses and adheres to the heat absorber 9 due to a heat-absorbing process of the refrigerant taking place in the heat absorber 9 at this time, thus cooling and dehumidifying the air. The dispersed residual refrigerant flowing into the refrigerant line 13J is decompressed in the outdoor expansion valve 6 and then evaporates in the outdoor heat exchanger 7.

[0050] The refrigerant evaporated in the heat absorber 9 flows out to the refrigerant line 13C to combine with the refrigerant (the refrigerant from the outdoor heat exchanger 7) from the refrigerant line 13D, and then flows successively through the check valve 40 and the accumulator 12 to be drawn into the compressor 2, thus repeating this cycle. The air dehumidified in the heat absorber 9 is reheated as it passes through the radiator 4, thus dehumidifying and heating the vehicle interior.

[0051] The controller 32 controls the rotation speed of the compressor 2 based on the target chiller pressure PCO calculated from the target heating temperature TCO and the chiller pressure PCI (the high pressure of the refrigerant circuit R) detected by the chiller pressure sensor 47, and the controller controls the valve position of the outdoor expansion valve 6 based on the temperature (the heat absorber temperature Te) of the heat absorber 9 detected by the chiller temperature sensor 48. (3) Internal circulation operation

[0052] Next, the internal circulation operation is described using Fig. 5 described. Fig. 5 shows the flow rate (solid line arrows) of the refrigerant of the refrigerant circuit R in the internal circulation operation. In the internal circulation operation, in the above state of the dehumidification and heating mode, the controller 32 completely closes the outdoor expansion valve 6 (a fully closed position). However, the solenoid valve 21 is kept open, and the refrigerant outlet of the outdoor heat exchanger 7 is connected to the refrigerant suction side of the compressor 2. That is, this internal circulation operation is a state in which the outdoor expansion valve 6 is completely closed by controlling the outdoor expansion valve 6 in the dehumidification and heating mode, and thus, this internal circulation operation can also be detected as part of the dehumidification and heating mode (with the shutter 23 opened).

[0053] However, the outdoor expansion valve 6 is closed, preventing the inflow of refrigerant into the outdoor heat exchanger 7, and thus all the condensed refrigerant flowing through the radiator 4 into the refrigerant line 13E flows through the solenoid valve 22 to the refrigerant line 13F. Then, the refrigerant flowing through the refrigerant line 13F flows from the refrigerant line 13B through the solenoid valve 17 to the indoor expansion valve 8. The refrigerant is decompressed in the indoor expansion valve 8 and then flows into the heat absorber 9 to evaporate. At this time, the water in the air blown out from the indoor fan 27 condenses to adhere to the heat absorber 9 by absorbing heat from the heat absorber 9, and thus the air is cooled and dehumidified.

[0054] The refrigerant evaporated in the heat absorber 9 flows into the refrigerant line 13C, flows successively through the check valve 40 and the accumulator 12, and is sucked into the compressor 2, thus repeating this cycle. The air dehumidified in the heat absorber 9 is reheated as it flows through the cooler 4, thus dehumidifying and heating the vehicle interior. However, during this internal circulation operation, the refrigerant circulates between the cooler 4 (heat radiation) and the heat absorber 9 (heat absorption), which are located inside the air flow channel 3. Thus, the heat is not pumped up from the outside air, but rather the heating power is exerted by the power consumed by the compressor 2.The entire amount of refrigerant passes through the heat absorber 9, which performs a dehumidification operation, and therefore, compared with the above dehumidification and heating mode, a dehumidification performance is higher, but the heating performance becomes low.

[0055] Further, the outdoor expansion valve 6 is closed, but the solenoid valve 21 is open, and the refrigerant outlet of the outdoor heat exchanger 7 communicates with the refrigerant suction side of the compressor 2. Thus, the liquid refrigerant in the outdoor heat exchanger 7 flows out through the refrigerant line 13D and the solenoid valve 21 to the refrigerant line 13C and is returned to the accumulator 12, so that the outdoor heat exchanger 7 is exposed to a state of the gaseous refrigerant therein. Thus, compared to the case where the solenoid valve 21 is closed, the amount of refrigerant circulating in the refrigerant circuit R is increased, whereby the heating capacity of the chiller 4 and the dehumidification capacity of the heat absorber 9 can be increased.

[0056] The controller 32 controls the speed of the compressor 2 depending on the temperature of the heat absorber 9 or the aforementioned cooler pressure PCI (the high pressure of the refrigerant circuit R). At this time, the controller 32 selects a lower compressor target speed from the compressor target speeds calculated from the temperature of the heat absorber 9 and the cooler pressure PCI to control the compressor 2. (4) Dehumidification and cooling mode

[0057] Next, the dehumidification and cooling mode is selected using Fig. 6 described. Fig. Figure 6 shows the flow rate (solid line arrows) of the refrigerant of the refrigerant circuit R in the dehumidification and cooling mode. In the dehumidification and cooling mode, the controller 32 opens the solenoid valve 17 and closes the solenoid valve 21. The controller also closes the solenoid valve 22 and the solenoid valve 20. Then, the controller controls the compressor 2 and the corresponding fans 15 and 27, and the air mix damper 28 is in a state where a ratio is set at which the air blown by the indoor fan 27 is to pass through the cooler 4. Furthermore, the shutter 23 is opened. The high-temperature, high-pressure gas refrigerant discharged from the compressor 2 thus flows into the cooler 4.The air in the air flow channel 3 flows through the cooler 4, and thus the air in the air flow channel 3 is heated by the high-temperature refrigerant in the cooler 4, while the refrigerant in the cooler 4 has the heat absorbed by the air and is cooled to condense and liquefy.

[0058] The refrigerant flowing out of the radiator 4 flows through the refrigerant line 13E to the outdoor expansion valve 6 and flows into the outdoor heat exchanger 7 through the outdoor expansion valve 6, which is controlled to be slightly open. The refrigerant flowing into the outdoor heat exchanger 7 is cooled therein by the air flow or the outside air supplied by the outdoor fan 15 to condense. The refrigerant flowing out of the outdoor heat exchanger 7 flows through the refrigerant line 13A and the check valve 18 into the refrigerant line 13B and further flows through the solenoid valve 17 to reach the indoor expansion valve 8. The refrigerant is decompressed in the indoor expansion valve 8 and then flows into the heat absorber 9 to evaporate.

[0059] The water in the air blown out from the indoor fan 27 condenses to adhere to the heat absorber 9 through the heat absorption process at this time, so that the air is cooled and dehumidified.

[0060] The refrigerant evaporated in the heat absorber 9 passes through the check valve 40 through the refrigerant line 13C into the accumulator 12 and flows through it for suction into the compressor 2, thus repeating this cycle. The air cooled and dehumidified in the heat absorber 9 is reheated as it passes through the cooler 4 (reheating: lower radiant power than during heating), thus dehumidifying and cooling the vehicle interior.

[0061] The controller 32 controls, based on the temperature (the heat absorber temperature Te) of the heat absorber 9 detected by the heat absorber temperature sensor 48 and a target heat absorber temperature TEO as its set value, the rotational speed of the compressor 2 to adjust the heat absorber temperature Te to the target heat absorber temperature TEO, and controls, based on the radiator pressure PCI (the high pressure of the refrigerant cycle R) detected by the radiator pressure sensor 47 and the radiator set pressure PCO (the set value of the radiator pressure PCI) calculated from the target heating temperature TCO, the valve position of the outdoor expansion valve 6 to adjust the radiator pressure PCI to the radiator set pressure PCO and thus obtain a required reheating by the radiator 4. (5) Cooling mode

[0062] Next, the cooling mode is selected based on Fig. 7 described. Fig. Figure 7 shows the flow rate (solid line arrows) of the refrigerant in the refrigerant circuit R in cooling mode. In cooling mode, the controller 32 opens the solenoid valve 20 in the above dehumidification and cooling mode state (the valve position of the outdoor expansion valve 6 is free). Note that the air mix damper 28 is in a state where the ratio at which the air is to be passed through the cooler 4 is set. Furthermore, the shutter 23 is opened.

[0063] As a result, the high-temperature, high-pressure gas refrigerant discharged from the compressor 2 flows into the cooler 4. The air in the air flow channel 3 passes through the cooler 4, but its ratio becomes small (because it is only reheated during cooling). Thus, the refrigerant only passes through the cooler, and the refrigerant discharged from the cooler 4 flows through the refrigerant line 13E to the outdoor expansion valve 6. At this time, the solenoid valve 20 is opened, and thus the refrigerant flows through the solenoid valve 20 to pass through the refrigerant line 13J and thus flows into the outdoor heat exchanger 7, where the refrigerant therein is cooled by the vehicle or the outside air by the outdoor fan 15 to condense and liquefy.The refrigerant flowing out of the outdoor heat exchanger 7 flows through the refrigerant line 13A and the check valve 18 into the refrigerant line 13B, and then flows through the solenoid valve 17 to reach the indoor expansion valve 8. The refrigerant is decompressed in the indoor expansion valve 8 and then flows into the heat absorber 9 to evaporate. At this time, the water in the air blown out by the indoor fan 27 condenses on the heat absorber 9 through the heat-absorbing process, thereby cooling the air.

[0064] The refrigerant evaporated in the heat absorber 9 flows into the refrigerant line 13C and enters the accumulator 12 via the check valve 40, flows through the accumulator, and is drawn into the compressor 2, thus repeating this cycle. The air cooled and dehumidified in the heat absorber 9 is discharged from the outlet 29 into the vehicle interior, thus cooling the vehicle interior. In this cooling mode, the controller 32 controls the speed of the compressor 2 depending on the temperature (the heat absorber temperature Te) of the heat absorber 9, which is detected by the heat absorber temperature sensor 48. (6) Change of air conditioning operation and control of the air mix damper 28

[0065] The controller 32 calculates the above-mentioned target outlet temperature TAO from the following formula (I). The target outlet temperature TAO is a target value for the temperature of the air to be discharged from the outlet 29 into the vehicle interior. TAO=(Tset-Tin)×K+Tbal(f(Test,SUN,Tam)) where Tset is a predetermined temperature of the vehicle interior set by the air conditioning control part 53, Tin is a temperature of the vehicle interior air detected by the inside air temperature sensor 37, K is a coefficient, and Tbal is a compensation value calculated from the predetermined temperature Tset, a solar radiation amount SUN detected by the solar radiation sensor 51, and the outside air temperature Tam detected by the outside air temperature sensor 33. Moreover, in general, the lower the outside air temperature Tam, the higher the target outlet temperature TAO becomes, and the higher the outside air temperature Tam, the lower the target outlet temperature TAO becomes.

[0066] Subsequently, the controller 32 selects any one of the above-mentioned air conditioning modes based on the outside air temperature Tam detected by the outside air temperature sensor 33 and the target outlet temperature TAO upon power-up. Furthermore, after power-up, the controller selects and changes the above-mentioned respective air conditioning modes depending on changes in the ambient and setting conditions, such as the outside air temperature Tam and the target outlet temperature TAO.

[0067] Furthermore, the controller 32 controls the air mixing damper 28 with an air volume flow ratio SW, which results from the formula SW = (TAO-Te) / (TH-Te). The air volume ratio SW is a ratio at which the air passed through the heat absorber 9 is to be passed through the cooler 4 and alternates between 0 (where the air is not passed through the cooler 4) and 1 (where all the air is passed through the cooler 4).

[0068] TH for calculating the air volume ratio SW of the air mix damper 28 is a temperature (a heating temperature) of the air on the leeward side of the aforementioned cooler 4. The controller 32 estimates TH from a first-order delay calculation formula (II) as shown below: TH=(INTL×TH0+Tau×THz) / (Tau+INTL) where INTL is a calculation period (constant), Tau is a time constant of a first-order delay, TH0 is a steady-state value of the heating temperature TH in a steady state before a first-order delay calculation, and THz is a previous value of the heating temperature TH. By estimating the heating temperature TH in this way, a dedicated temperature sensor can be omitted. Incidentally, the controller 32 changes the above time constant Tau and the steady-state value TH0 according to the above-mentioned operation mode, thereby changing the above-described estimation formula (II) depending on the operation mode for estimating the heating temperature TH. (7) Battery temperature adjustment 55

[0069] Next, with reference to Fig. 8 and Fig. 9 illustrates the temperature adjustment control of the battery 55 by the controller 32. When the battery 55 is charged / discharged in a state where its temperature becomes high due to its self-heating or the like as described above, its deterioration progresses. Thus, the controller 32 of the vehicle air conditioner 1 of the embodiment cools the temperature of the battery 55 to an appropriate temperature range through the heat generating device temperature adjusting device 61 while the air conditioner is operated as described above. Note that the appropriate temperature range of the battery 55 is generally from above +25°C to below +45°C, so the target battery temperature TBO (e.g., +35°C) as the target temperature (the battery temperature Tb) of the battery 55 in the embodiment is set to the appropriate temperature range. (7-1) First heat carrier heat absorption / heating mode (heat carrier heat absorption / heating mode)

[0070] In heating mode ( Fig. 3) the controller 32 calculates, for example, using the following formulas (III) and (IV), a target heating capacity TGQhp, which is the heating capacity of the vehicle interior required for the radiator 4, and a heating capacity Qhp that can be generated by the radiator 4. TGQhp=(TCO−Te)×Cpa×ρ×Qair Qhp=f(Tam,NC,BLV,VSP,FANVout,Te) where Te is a temperature of the heat absorber 9 detected by the heat absorber temperature sensor 48, Cpa is a specific heat of the air flowing into the cooler 4 [kj / kg K], ρ is a density of the air flowing into the cooler 4 (specific volume) [kg / m3], Qair is an amount of air flowing through the cooler 4 [m 3 / h] (estimated from the fan voltage BLV of the indoor fan 27, etc.), VSP is a speed obtained from the speed sensor 52, and FANVout is a voltage of the outdoor fan 15.

[0071] Further, the controller 32 calculates a required battery cooling capacity Qbat, which is a cooling capacity of the battery 55 required for the heat generating device temperature adjusting device 61, for example, according to the following formula (V) based on the temperature (the battery temperature Tb) of the battery 55 detected by the battery temperature sensor 76 and the above-mentioned battery target temperature TBO. Qbat=(Tb−TBO)×k1×k2 where k1 is a specific heat of the heat carrier circulating in the heat generating device temperature adjusting device 61 [kJ / kg K], and k2 is a flow rate of the heat carrier [kg / h]. Incidentally, the formula for calculating the required battery cooling capacity Qbat is not limited to the above; the required battery cooling capacity can be calculated in addition to other factors related to battery cooling.

[0072] If the battery temperature Tb is lower than the battery target temperature TBO (Tb <TBO) ist, wird die in der obigen Formel (V) berechnete erforderliche Batteriekühlleistung Qbat zu einem Minus, und daher schließt der Regler 32 in der Ausführung das Hilfsexpansionsventil 73 vollständig und stoppt auch die Wärmeerzeugungseinrichtungs-Temperatureinstellvorrichtung 61. Steigt dagegen die Batterietemperatur Tb durch Laden / Entladen o.ä. an und wird während des oben beschriebenen Heizmodus (TBO<Tb) höher als die Batterie-Solltemperatur TBO, wird die in der Formel (V) berechnete erforderliche Batteriekühlleistung Qbat ins Plus gedreht, und somit öffnet in der Ausführungsform der Regler 32 das Hilfsexpansionsventil 73 und betätigt die Wärmeerzeugungseinrichtungs-Temperatureinstellvorrichtung 61, um die Kühlung der Batterie 55 zu starten.

[0073] In this case, the controller 32 compares the two values ​​of the target heating capacity TGQhp and the required battery cooling capacity Qbat described above based on the target heating capacity TGQhp and the required battery cooling capacity Qbat, and changes and executes the first heat carrier heat absorption / heating mode to be described here and a second heat carrier heat absorption / heating mode to be described later in the embodiment description (both are the heat carrier heat absorption / heating mode in the present invention).

[0074] First, when the heating load of the vehicle interior is high (e.g., at low room air temperature) and the heat generation from the battery 55 is low (at low cooling load) (TGQhp>Qbat), the controller 32 executes the first heat carrier heat absorption / heating mode if the target heating capacity TGQhp is greater than the required battery cooling capacity Qbat. Fig. 8 shows the flow rate (solid line arrows) of the refrigerant of the refrigerant circuit R in the first heat carrier heat absorption / heating mode and the flow rate (dashed line arrows) of the heat carrier of the heat generating device temperature adjusting device 61.

[0075] In the first heat transfer medium heat absorption / heating mode, the controller 32 has the state that it is in the heating mode state of the refrigerant circuit R according to Fig. 3 further opens the solenoid valve 22 and also opens the auxiliary expansion valve 73 to control its valve position. Subsequently, the controller operates the circulation pump 62 of the heat generator temperature adjusting device 61. Thus, a portion of the refrigerant discharged from the radiator 4 is distributed to a refrigerant supply side of the outdoor expansion valve 6 and flows through the refrigerant line 13F to a refrigerant supply side of the solenoid valve 17. The refrigerant then enters the branch line 72, is expanded in the auxiliary expansion valve 73, and then flows through the branch line 72 into the refrigerant passage 64B of the refrigerant-heat-transfer medium heat exchanger 64 for evaporation. At this time, a heat-absorbing effect is exerted.A cycle is repeated in which the refrigerant evaporated in the refrigerant passage 64B flows successively through the refrigerant line 74, the refrigerant line 13C and the accumulator 12 and is sucked into the compressor 2 (this is shown by the solid arrows in . Fig. 8 shown).

[0076] On the other hand, the heat transfer fluid exiting the circulation pump 62 flows through the heat transfer fluid heater 66 into the heat transfer fluid line 68 to enter the heat transfer fluid passage 64A of the refrigerant-heat transfer fluid heat exchanger 64, where it absorbs heat from the refrigerant evaporated in the refrigerant passage 64B, thereby cooling the heat transfer fluid. The heat transfer fluid cooled by the heat absorption process of the refrigerant flows out of the refrigerant-heat transfer fluid heat exchanger 64 and reaches the battery 55 to cool the battery 55, and the heat transfer fluid is then sucked into the circulation pump 62, thereby repeating this cycle (indicated by the dashed line arrows in Fig. 8).

[0077] Consequently, in the first heat-transfer heat absorption / heating mode, the refrigerant of the refrigerant circuit R evaporates in the outdoor heat exchanger 7 and the refrigerant-to-heat-transfer heat exchanger 64, absorbs heat from the outside air, and also absorbs heat from the heat transfer medium (battery 55) of the heat generating device temperature adjusting device 61. Thus, the heat from the battery 55 is pumped up through the heat transfer medium, and the pumped-up heat can be transferred to the radiator 4 and used for heating the vehicle interior while cooling the battery 55.

[0078] In the first heat carrier heat absorption / heating mode, when it is not possible to achieve the target heating capacity TGQhp by the above-described heating capacity Qhp of the radiator 4 also by the heat absorption from the outside air and the heat absorption from the battery 55 as described above (TGQhp>Qhp), the controller 32 lets the heat carrier warm-up heater 66 generate heat (switching on).

[0079] When heat is generated by the heat medium heating heater 66, the heat medium discharged from the circulation pump 62 of the heat generating device temperature adjusting device 61 is heated in the heat medium heating heater 66 and then flows into the heat medium passage 64A of the refrigerant-heat medium heat exchanger 64. Thus, the heat of the heat medium heating heater 66 is also pumped up by the refrigerant evaporated in the refrigerant passage 64B, thereby increasing the heating capacity Qhp by the radiator 4, whereby the target heating capacity TGQhp can be achieved. Incidentally, the controller 32 stops the heat generation of the heat medium heating heater 66 when the target heating capacity TGQhp for the heating capacity Qhp is reached (not turned on). (7-2) Second heat carrier heat absorption / heating mode

[0080] Then, when the heating load of the vehicle interior and the cooling load of the battery 55 are almost equal, that is, when the target heating capacity TGQhp and the required battery cooling capacity Qbat are equal to or close to each other (TGQhp≈Qbat), the controller 32 executes the second heat carrier heat absorption / heating mode. Fig. 9 shows the flow rate of the refrigerant of the refrigerant circuit R in the second heat carrier heat absorption / heating mode (solid line arrows) and the flow rate of the heat carrier of the heat generating device temperature adjusting device 61 (dashed line arrows).

[0081] In the second heat transfer medium heat absorption / heating mode, the controller 32 is in a state where it closes the solenoid valves 17, 20, and 21, completely closes the outdoor expansion valve 6, opens the solenoid valve 22, and also opens the auxiliary expansion valve 73 to control its valve position. Subsequently, the controller controls the compressor 2 and the indoor fan 27, and also operates the circulation pump 62 of the heat generator temperature adjusting device 61. Thus, all the refrigerant discharged from the radiator 4 flows into the solenoid valve 22 and reaches the refrigerant side upstream of the solenoid valve 17 via the refrigerant line 13F. The refrigerant then enters the branch line 72 and is decompressed in the auxiliary expansion valve 73. Then, it flows through the branch line 72 into the refrigerant passage 64B of the refrigerant-to-heat-transfer medium heat exchanger 64 for evaporation. At this time, a heat-absorbing process is performed.A cycle is repeated in which the refrigerant evaporated in the refrigerant passage 64B flows successively through the refrigerant line 74, the refrigerant line 13C and the accumulator 12 and is sucked into the compressor 2 (this is shown by the solid arrows in . Fig. 9).

[0082] On the other hand, the heat transfer fluid exiting the circulation pump 62 flows through the heat transfer fluid warm-up heater 66 into the heat transfer fluid line 68 to enter the heat transfer fluid passage 64A of the refrigerant-heat transfer fluid heat exchanger 64, where it absorbs heat from the refrigerant evaporated in the refrigerant passage 64B, thereby cooling the heat transfer fluid. The heat transfer fluid cooled by the heat absorption operation of the refrigerant flows out of the refrigerant-heat transfer fluid heat exchanger 64 and reaches the battery 55 to cool the battery 55, and the heat transfer fluid is then sucked into the circulation pump 62, thereby repeating this cycle (indicated by the dashed line arrows in Fig. 9).

[0083] Consequently, in the second heat-transfer heat absorption / heating mode, the refrigerant of the refrigerant circuit R evaporates in the refrigerant-transfer heat exchanger 64 and only absorbs heat from the heat transfer medium (battery 55) of the heat generating device temperature adjustment device 61. Consequently, the refrigerant does not flow into the exterior heat exchanger 7 and only pumps up the heat from the battery 55 through the heat transfer medium. Therefore, the battery 55 is cooled, and the heat pumped up from the battery 55 is transferred to the radiator 4, enabling heating of the vehicle interior without causing icing of the exterior heat exchanger 7.

[0084] By the way, even in the above-mentioned operating modes dehumidification and heating mode ( Fig. 4), internal circulation operation ( Fig. 5), dehumidification and cooling mode ( Fig. 6) and cooling mode ( Fig. 7) the auxiliary expansion valve 73 is opened to control its valve position and the circulation pump 62 is actuated, whereby the refrigerant in the refrigerant passage 64B of the refrigerant-heat-transfer medium heat exchanger 64 is evaporated and heat is absorbed from the heat-transfer medium, thereby cooling the battery 55 to adjust its temperature. (8) Switching the control from heating mode to the first and second heat carrier heat absorption / heating mode when there is a possibility that heat absorption from the outside air becomes impossible

[0085] Next, the change of control from the heating mode to the first and second heat carrier heat absorption / heating mode is explained with reference to Fig. 10 to 14, if there is a possibility that the refrigerant will not be able to absorb heat from the outside air in the outdoor heat exchanger 7 during the heating mode ( Fig. 3) (Impossibility of heat absorption).

[0086] After the above heating mode in Fig. 10, step S1, the controller 32 executes step S3 while executing the heating mode in step S2 to judge whether there is a possibility that the refrigerant will not be able to absorb heat from the outside air in the outdoor heat exchanger 7. A judgment condition in this step S3 is referred to as an outside air heat non-absorbable prediction and judgment condition. The outside air heat non-absorbable prediction and judgment condition is, for example, one of the conditions (i) to (v) listed below, or a combination thereof, or all of them. (i) The refrigerant suction temperature Ts of the compressor 2 detected by the suction temperature sensor 44 is reduced to a predetermined value Ts1 or less, (ii) The frosting amount of the outdoor heat exchanger 7 is increased to a predetermined value Fr1 or higher, (iii) The rate of progression of frosting of the outdoor heat exchanger 7 is increased to a predetermined value X1 or higher, (iv) the outside air temperature Tam detected by the outside air temperature sensor 33 is reduced to a predetermined value Tam1 or less, and (v) The decreasing speed of the outside air temperature Tam detected by the outside air temperature sensor 33 is increased to a value Y1 or higher.

[0087] There is a possibility that the refrigerant will not be able to absorb heat from the outside air in the outdoor heat exchanger 7 in a state where frost formed in the outdoor heat exchanger 7 grows and in an environment where the outside air temperature Tam is reduced. Incidentally, the above condition (i) is based on the fact that when the outside air temperature Tam is reduced or when frost forms in the outdoor heat exchanger 7, which makes it difficult to absorb heat from the outside air, the suction temperature Ts of the compressor 2 is lowered.Further, the amount of frosting and the rate of progress of frosting under the above conditions (ii) and (iii) can be determined, for example, from the difference between the outdoor temperature TXO and the outdoor heat exchanger pressure PXO of the outdoor heat exchanger 7 and their values ​​(an outdoor heat exchanger temperature TXObase at the time of non-frosting and an outdoor heat exchanger pressure PXObase at the time of non-frosting, which are determined in advance).

[0088] The above-mentioned predetermined values ​​Ts1, Fr1, X1, Tam1, and Y1 are determined through preliminary tests as values ​​at which there is a possibility that the refrigerant will be unable to absorb heat from the outside air in the outdoor heat exchanger 7. Then, when any of the above-mentioned conditions (i) to (v), or their combination, or all of them are met in step S3, the controller 32 determines that there is a possibility that the prediction and judgment condition that outside air heat is not absorbable occurs, and the refrigerant will be unable to absorb heat from the outside air in the outdoor heat exchanger 7, and then proceeds to step S4, in which the controller first actuates the circulation pump 62 of the heat generator temperature adjusting device 61 to circulate the heat medium in the heat medium line 68.

[0089] Subsequently, in step S5, the controller 32 judges, based on the output of the heat medium temperature sensor 80, whether the temperature (the heat medium temperature Tw) of the heat medium flowing out of the heat medium warm-up heater 66 is a predetermined threshold value T1 or less. In this case, the controller 32 has a heat absorption-adaptable heat medium temperature MAP, which is Fig. 11. The heat absorption adaptable heat medium temperature MAP shows the relationship between the above-mentioned target heating capacity TGQhp and the above-mentioned threshold T1, which is the heat medium temperature Tw at which it cannot be reached. The higher the target heating capacity TGQhp of the chiller 4 becomes, the higher the threshold T1 becomes.

[0090] Incidentally, the threshold value T1 may be determined based on any one of the above-mentioned target outlet temperature TAO and the blower voltage BLV of the indoor blower 27 and the above-mentioned target heating temperature TCO, or a combination of these and the target heating capability TGQhp, or all of these and even another such target heating capability TGQhp.

[0091] In step S5, the controller 32 determines the threshold T1 from the heat absorption-adaptable heat medium temperature MAP and the target heating capability TGQhp at that time, and judges whether the heat medium temperature Tw is equal to or lower than the threshold T1. Then, if the heat medium temperature Tw is low and the threshold T1 is less than or equal to, the controller 32 determines that the vehicle interior cannot be heated by the heat absorption of the heat medium, and then proceeds from step S5 to step S9, where the controller starts heat medium preheating.

[0092] During heat transfer medium preheating, controller 32 controls heat transfer medium heater 66 to generate heat. As the heat transfer medium circulated in circulation pump 62 is heated by heat transfer medium heater 66, the heat transfer medium temperature Tw rises. When the heat transfer medium temperature Tw then exceeds threshold T1 (which can be a value (T1+α1) with a predetermined hysteresis α1), controller 32 proceeds to step S6.

[0093] In this step S6, the controller 32 judges whether the refrigerant is still capable of absorbing heat from the outside air in the outdoor heat exchanger 7. A judgment condition in this step S6 is referred to as an outside air heat absorbability judgment condition. The outside air heat absorbability judgment condition is, for example, one of the conditions (vi) to (x) listed below, or a combination thereof, or all of them. (vi) The temperature Ts of the compressor 2 detected by the suction temperature sensor 44 is lower than the predetermined value Ts1 by a predetermined value Ts2 or higher, (vii) The frosting amount of the outdoor heat exchanger 7 is larger than the predetermined value Fr1 by a predetermined value Fr2 or less, (viii) The rate of progression of frosting of the outdoor heat exchanger 7 is faster than the predetermined value X1 by a predetermined value X2 or less, (ix) the outside air temperature Tam detected by the outside air temperature sensor 33 is lower than the predetermined value Tam1 by a predetermined value Tam2 or higher, and (x) The decreasing speed of the outside air temperature Tam detected by the outside air temperature sensor 33 is faster than the predetermined value Y1 by a predetermined value Y2 or less.

[0094] The above-mentioned predetermined values ​​Ts2, Fr2, X2, Tam2, and Y2 are determined through preliminary tests as values ​​at which the refrigerant is still capable of absorbing heat from the outside air in the outdoor heat exchanger 7. If one of the above-mentioned conditions (vi) to (x) or their combination or all of them occur in step S6, the controller 32 determines that the judgment condition that outside air heat is absorbable is established and the refrigerant is still capable of absorbing heat from the outside air in the outdoor heat exchanger 7, and then proceeds to step S7, in which the controller selects the above-mentioned first heat carrier heat absorption / heating mode ( Fig. 8) executes (performs the switch to the first heat carrier heat absorption / heating mode).

[0095] In the first heat-transfer heat absorption / heating mode, as described above, the refrigerant of the refrigerant circuit R evaporates in the outdoor heat exchanger 7 and the refrigerant-to-heat-transfer heat exchanger 64, absorbing heat from the outside air and heat from the heat transfer medium of the heat generating device temperature adjusting device 61. Therefore, it is possible to pump up the heat of the battery 55 and the heat transfer medium warm-up heater 66 (when turned on) and transfer the pumped heat to the radiator 4 to use it for heating the vehicle interior.

[0096] On the other hand, if the judgment condition that outside air heat is absorbable is not established in step S6, the controller determines that the refrigerant is unable to absorb heat from the outside air in the outdoor heat exchanger 7, and proceeds to step S8, in which it executes the above-mentioned second heat carrier heat absorption / heating mode ( Fig. 9) (executes the switch to the second heat-transfer heat absorption / heating mode). Furthermore, the controller enables the heat-transfer heater 66 to generate heat as needed. This makes it possible to transfer the heat pumped up by the battery 55 and the heat-transfer heater 66 to the radiator 4 to heat the vehicle interior.

[0097] Fig. Figure 12 shows changes in the target outlet temperature TAO, the heating temperature TH, and the heat transfer medium temperature Tw during the transition from heating mode to the second heat transfer medium heat absorption / heating mode described above. In addition, NC indicates the speed of compressor 2, L1 the frosting amount of outdoor heat exchanger 7, and L2 the maximum value MAXNC of the speed NC of compressor 2. Then, a time t1 in Fig. 12 indicates a time at which the heat carrier preheating operation in step S9 of Fig. 10 is started, and t2 a time at which the second heat carrier heat absorption / heating mode is started in step S8.

[0098] When the heat medium temperature Tw is in a low state (e.g., 0 °C or so below the above-mentioned threshold value T1) and the heat medium preheating operation as step S9 of the embodiment is not performed, the heat medium temperature Tw increases from time t2 as shown by a dashed line in Fig. 12. Therefore, as shown by P1 in a pH diagram of Fig. 14, the discharge pressure of compressor 2 is low and the heating temperature TH is temporarily reduced, as shown by a dashed line in Fig. 12 is displayed even if the second heat carrier heat absorption / heating mode is started at time t2 (the NC speed of compressor 2 is also reduced). For this reason, a passenger feels uncomfortable.

[0099] On the other hand, if the heat medium preheating operation is carried out in step S9 before switching from the heating mode to the second heat medium heat absorption / heating mode as in the present invention, the heat medium temperature Tw increases from time t1 and is increased above the threshold value T1 (e.g. +20 °C) at time t2. Therefore, as shown by P2 in a pH diagram of Fig. 13, the discharge pressure of compressor 2 is high and the heating temperature TH rises without deviating from the target discharge temperature TAO, as shown by a solid line in Fig. 12, is greatly reduced by starting the second heat carrier heat absorption / heating mode at time t2 (the speed NC of compressor 2 also increases).

[0100] In the present invention, as described in detail above, the heat generating device temperature adjusting device 61 for circulating the heat carrier in the battery 55 (heat generating device) is provided, which is installed in the vehicle to regulate the temperature of the battery 55. The heat generating device temperature adjusting device 61 includes the heat carrier warm-up heater 66 for heating the heat carrier and the refrigerant-heat carrier heat exchanger 64 for heat exchange between the refrigerant and the heat carrier. The controller 32 has the first and second heat carrier heat absorption / heating modes for allowing the refrigerant discharged from the compressor 2 to radiate heat into the radiator 4, decompressing the refrigerant from which the heat has been radiated, and then allowing the refrigerant to absorb heat in the refrigerant-heat carrier heat exchanger 64.Therefore, when switching to the first and second heat medium heat absorption / heating modes, heat is absorbed from the heat medium of the heat generating device temperature adjustment device 61 to enable efficient heating of the vehicle interior. For example, even if cooling of the battery 55 is adequately performed while suppressing frosting of the exterior heat exchanger 7, or frost is formed in the exterior heat exchanger 7 so that it cannot absorb heat from the outside air, heat is absorbed from the heat medium of the heat generating device temperature adjustment device 61 to enable heating of the vehicle interior.

[0101] Specifically, when the heat medium temperature Tw is the predetermined threshold T1 or lower when switching from the heating mode to the first and second heat medium heat absorption / heating modes, the controller 32 heats the heat medium through the heat medium warm-up heater 66 before switching to the first and second heat medium heat absorption / heating modes to raise the temperature of the heat medium, and then switches to the first and second heat medium heat absorption / heating modes. This makes it possible to ensure sufficient heating performance when switching from the heating mode to the first and second heat medium heat absorption / heating modes.Thus, the disadvantage that the heating mode is switched to the first and second heat-medium heat absorption / heating modes in the low heat-medium temperature state and the temperature (outlet temperature which coincides with the heater temperature TH) of the air blown from the outlet 29 into the vehicle interior is temporarily lowered, so that the passenger feels uncomfortable and uneasy can also be eliminated.

[0102] Furthermore, in the embodiment, when the predetermined prediction and judgment condition that outside air heat is not absorbable is established in the heating mode, the controller 32 determines that there is a possibility that it will not be able to absorb heat from the outside air in the outdoor heat exchanger 7 and judges whether the temperature of the heat medium is the threshold T1 or less. If the temperature is the threshold T1 or less, the controller starts heating the heat medium by the heat medium warm-up heater 66 and enters the first and second heat medium heat absorption / heating modes to wait for the temperature of the heat medium to rise to at least a temperature (higher than the threshold T1 or a temperature higher than T1+α1) higher than the threshold T1, thereby enabling a smooth transition from the heating mode to the first and second heat medium heat absorption / heating modes.

[0103] The prediction and judgment condition that outside air heat is not absorbable preferably includes at least one of the following conditions as included in the embodiment: reducing the refrigerant suction temperature Ts of the compressor 2 to the predetermined value Ts1 or less, increasing the frosting amount of the outdoor heat exchanger 7 to the predetermined value Fr1 or higher, increasing the progress speed of frosting of the outdoor heat exchanger 7 to the predetermined value X1 or higher, reducing the outside air temperature Tam to the predetermined value Tam1 or less, and increasing the reduction speed of the outside air temperature Tam to the predetermined value Y1 or higher.

[0104] Further, in the embodiment, the controller 32 determines the threshold value T1 based on at least one of the following values: the target heating capacity TGQhp of the radiator 4, the target outlet temperature TAO, which is the target temperature of the air blown into the vehicle interior, the blower voltage BLV of the interior blower 27 at which the air is to be passed through the air flow duct 3, and the target heating temperature TCO, which is the target temperature (the heating temperature TH) of the air on the leeward side of the radiator 4. Therefore, the controller is able to appropriately detect whether heating of the heat carrier by the heat carrier warm-up heater 66 is necessary and avoid unnecessary heating by the heat carrier warm-up heater 66.

[0105] Furthermore, in the embodiment, when the predetermined judgment condition that outside air heat is absorbable is established, the controller 32 determines that absorption of heat from the outside air is possible in the outside heat exchanger 7, and executes the first heat-transfer medium heat absorption / heating mode to allow the refrigerant, from which heat has been radiated in the radiator 4, to absorb heat in the outside heat exchanger 7 and the refrigerant-to-heat-transfer medium heat exchanger 64. Therefore, when absorption of heat from the outside air is possible in the outside heat exchanger 7, it is possible to absorb heat from the outside air along with absorption of heat from the heat transfer medium, thereby heating the vehicle interior.

[0106] The judging condition that outside air heat is absorbable is preferably at least one of the following: the refrigerant suction temperature Ts of the compressor 2 is lower than the predetermined value Ts1 by the predetermined value Ts2 or higher, the frosting amount of the outdoor heat exchanger 7 is greater than the predetermined value Fr1 by the predetermined value Fr2 or less, the progress speed of frosting of the outdoor heat exchanger 7 is faster than the predetermined value X1 by the predetermined value X2 or less, the outside air temperature Tam is lower than the predetermined value Tam1 by the predetermined value Tam2 or higher, and the decreasing speed of the outside air temperature Tam is faster than the predetermined value Y1 by the predetermined value Y2 or less.

[0107] Incidentally, the constitutions of the refrigerant cycle R and the heat generating device temperature adjusting device 61 described in each of the above-mentioned embodiments are not limited thereto and are, of course, changeable within the scope not deviating from the gist of the present invention. Extract from the reference symbols 1 vehicle air conditioning system 2 compressor 3 Air flow channel 4 coolers 6 Outdoor expansion valve 7 outdoor heat exchangers 8 Internal expansion valve 9 heat absorbers 17, 20, 21, 22 Solenoid valve 27 internal fans 28 Air mixing flap 32 controller (control unit) 55 Battery (heat generating device) 61 Heat generating device temperature adjustment device 62 Circulation pump 64 refrigerant-heat transfer medium heat exchangers 66 Heat transfer medium heating (heating device) 72 branch line (branch circuit) 73 Auxiliary expansion valve 80 Heat transfer fluid temperature sensor R Refrigerant circuit.

Claims

[1] Vehicle air conditioning system (1), comprising: a compressor (2) for compressing a refrigerant; an air flow channel (3) through which the air to be supplied to a vehicle interior flows; a cooler (4) which allows the refrigerant to radiate heat and thus heats the air to be supplied from the air flow duct (3) into the vehicle interior; an external heat exchanger (7) arranged outside the vehicle interior, which allows the refrigerant to absorb heat; and a control unit (32), wherein the control unit (32) is designed to carry out at least one heating process to allow the refrigerant discharged from the compressor (2) to radiate heat in the cooler (4), to decompress the refrigerant from which the heat has been radiated, and then to allow the refrigerant to absorb heat in the outdoor heat exchanger (7), wherein the vehicle air conditioning system (1) comprises a heat generating device temperature adjusting device (61) for circulating a heat carrier in a heat generating device (55) mounted in a vehicle to adjust the temperature of the heat generating device (55), wherein the heat generating device temperature adjusting device (61) comprises a heating device (66) for heating the heat carrier and a refrigerant-heat carrier heat exchanger (64) for heat exchange between the refrigerant and the heat carrier, wherein the control unit (32) has a heat carrier heat absorption / heating mode for allowing the refrigerant discharged from the compressor (2) to radiate heat into the cooler (4), decompressing the refrigerant from which the heat has been radiated, and then allowing the refrigerant to absorb heat in the refrigerant-heat carrier heat exchanger (64), and wherein, when the temperature of the heat carrier is a predetermined threshold value T1 or less when switching from the heating operation to the heat carrier heat absorption / heating mode, the control device (32) is configured to heat the heat carrier by the heating device (66) to increase the temperature of the heat carrier before switching to the heat carrier heat absorption / heating mode, and then to perform the switch to the heat carrier heat absorption / heating mode. [2] The vehicle air conditioner (1) according to claim 1, wherein, when a predetermined prediction and judgment condition that outside air heat is not absorbable is set in the heating operation, the controller (32) is configured to determine that there is a possibility that it will not be able to absorb heat from the outside air in the outdoor heat exchanger (7) and judges whether the temperature of the heat carrier is equal to the threshold value T1 or less, and when the temperature thereof is equal to the threshold value T1 or less, the controller (32) is configured to start heating the heat carrier by the heater (66) and to enter the heat carrier heat absorption / heating mode until the temperature of the heat carrier has risen to at least a temperature higher than the threshold value T1. [3] The vehicle air conditioner (1) according to claim 2, wherein the prediction and judgment condition that outside air heat is not absorbable includes at least one of the following conditions: reducing a refrigerant suction temperature Ts of the compressor (2) to a predetermined value Ts1 or less, increasing a frosting amount of the outdoor heat exchanger (7) to a predetermined value Fr1 or higher, increasing a progress speed of frosting of the outdoor heat exchanger (7) to a predetermined value X1 or higher, reducing an outside air temperature Tam to a predetermined value Tam1 or less, and increasing a reduction speed of the outside air temperature Tam to a predetermined value Y1 or higher. [4] Vehicle air conditioning system (1) according to one of claims 1 to 3, wherein the control unit (32) is configured to determine the threshold value T1 on the basis of at least one of the following values: a target heating capacity TGQhp of the radiator (4), a target outlet temperature TAO, which is a target value of a temperature of the air blown into the vehicle interior, a voltage BLV of an interior blower (27) with which the air is to be passed through the air flow duct (3), and a target heating temperature TCO, which is a target value of a temperature of the air on the leeward side of the radiator (4). [5] The vehicle air conditioner (1) according to any one of claims 1 to 4, wherein, when a predetermined judgment condition that outside air heat is absorbable is set in the execution of the heat carrier heat absorption / heating mode, the control device (32) is configured to determine that absorption of heat from the outside air is possible in the outdoor heat exchanger (7), and to allow the refrigerant from which heat has been radiated in the radiator (4) to absorb heat in the outdoor heat exchanger (7) and the refrigerant-heat carrier heat exchanger (64). [6] The vehicle air conditioner (1) according to claim 5, wherein the judging condition that outside air heat is absorbable includes at least one of the following conditions: the refrigerant suction temperature Ts of the compressor (2) is lower than the predetermined value Ts1 by a predetermined value Ts2 or higher, the frosting amount of the outdoor heat exchanger (7) is greater than the predetermined value Fr1 by a predetermined value Fr2 or less, the progress speed of frosting of the outdoor heat exchanger (7) is faster than the predetermined value X1 by a predetermined value X2 or less, the outside air temperature Tam is lower than the predetermined value Tam1 by a predetermined value Tam2 or higher, and the decreasing speed of the outside air temperature Tam is faster than the predetermined value Y1 by a predetermined value Y2 or less.

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