Heat pump cycle device

Abstract

To provide a heat pump cycle device that can quickly achieve sufficient heating capacity. [Solution] The vehicle air conditioning system 1, which is a heat pump cycle device, comprises a compressor 11, a first three-way joint 13a, an indoor condenser 12, a cooling flow control valve 16c, a bypass passage 21c, a bypass-side flow control valve 16d, and an ejector 70. The ejector 70 has a nozzle section 71 that accelerates and injects the refrigerant flowing out of the bypass passage 21c, and a body section 72 in which a refrigerant suction port 721 is formed to draw in the gas-liquid two-phase refrigerant flowing out of the cooling flow control valve 16c. The ejector 70 raises the refrigerant pressure at the refrigerant outlet 723 to the refrigerant pressure at the refrigerant suction port 721 by the action of a shock wave.

Description

Technical Field

[0001] The present invention relates to a heat pump cycle device that heats an object to be heated using heat generated by compression work of a compressor. Background Art

[0002] Conventionally, Patent Document 1 discloses a heat pump cycle device that is applied to a vehicle air conditioner and heats blown air blown into a vehicle interior as an object to be heated. The heat pump cycle device of Patent Document 1 is configured to be capable of executing a hot gas heating mode as an operation mode for heating the vehicle interior when the outside air temperature is extremely low.

[0003] More specifically, in the heat pump cycle device of Patent Document 1, in the hot gas heating mode, the refrigerant circuit is switched to a refrigerant circuit that allows part of the discharged refrigerant discharged from the compressor to flow into the heating unit. In the heating unit, the blown air is heated using the discharged refrigerant as a heat source. Furthermore, the refrigerant flowing out of the heating unit and the remaining discharged refrigerant are depressurized by different flow rate adjustment valves, respectively, mixed, and then switched to a refrigerant circuit that sucks the mixture into the compressor.

[0004] That is, in the heat pump cycle device of Patent Document 1, in the hot gas heating mode, a gaseous phase refrigerant having a superheat degree obtained by depressurizing the discharged refrigerant and a gas-liquid two-phase refrigerant obtained by depressurizing the refrigerant that has radiated heat in the heating unit are mixed and switched to a refrigerant circuit that sucks the mixture into the compressor. Thereby, in the hot gas heating mode, even when the outside air temperature is extremely low and the refrigerant hardly absorbs heat from the outside air, the heat generated by the compression work of the compressor is used to heat the blown air, thereby realizing heating of the vehicle interior. Prior Art Documents Patent Documents

[0005] Patent Document 1 Japanese Unexamined Patent Application Publication No. 2021-156567 Summary of the Invention Problem to be Solved by the Invention

[0006] By the way, in the heat pump cycle device of Patent Document 1, in order to sufficiently heat the blown air in the heating section during the hot gas heating mode, it is necessary to sufficiently increase the compression work of the compressor. And to increase the compression work of the compressor, it is effective to increase the suction refrigerant pressure of the suction refrigerant drawn into the compressor and thereby increase the density of the suction refrigerant.

[0007] However, the hot gas heating mode described in Patent Document 1 is selected when the ambient temperature is extremely low. Therefore, when the hot gas heating mode is selected, the temperature of the refrigerant circulating in the cycle is often low, and the intake refrigerant pressure is also low. For this reason, when starting the hot gas heating mode, it is necessary to use the heat generated by the compression work of the compressor to raise the temperature of the refrigerant and increase the intake refrigerant pressure.

[0008] However, while the heat generated by the compressor's compression work is being used to raise the temperature of the refrigerant, the amount of compression work available to heat the blown air, which is the object to be heated, decreases. Therefore, in the heat pump cycle device of Patent Document 1, it is difficult to quickly raise the temperature of the object to be heated when switching to the hot gas heating mode.

[0009] In view of the above, the present invention aims to provide a heat pump cycle device that heats an object to be heated using the heat generated by the compression work of a compressor, and that can quickly exhibit sufficient heating capacity. [Means for solving the problem]

[0010] To achieve the above objective, the heat pump cycle device described in claim 1 comprises a compressor (11), an upstream branch section (13a), heating sections (12, 121, 60), heating section side flow rate adjustment sections (16a, 16b, 16c), a bypass passage (21c), a bypass side flow rate adjustment section (16d, 73), and ejectors (70, 70a).

[0011] The compressor compresses and discharges the refrigerant. The upstream branching section branches the flow of the refrigerant discharged from the compressor. The heating section heats the object to be heated using one of the refrigerant branches off at the upstream branching section as a heat source. The heating section flow rate adjustment section adjusts the flow rate of the refrigerant flowing out of the heating section. The bypass passage allows the other refrigerant branched off at the upstream branching section to flow, bypassing the heating section. The bypass flow rate adjustment section adjusts the flow rate of the refrigerant flowing through the bypass passage.

[0012] The ejector has a nozzle section (71) and a body section (72). The nozzle section accelerates and injects the refrigerant that has flowed out from the bypass passage. The body section has a refrigerant suction port (721) for drawing in the gas-liquid two-phase refrigerant that has been depressurized in the heating section side flow rate adjustment section, and a refrigerant outlet (723) for releasing the refrigerant that has flowed into the interior towards the compressor's suction port side.

[0013] The nozzle section has a throat section (713) and a flared section (714). The throat section is the part that narrows the passage cross-sectional area the most. The flared section is the part that widens the passage cross-sectional area as it moves from the throat section towards the nozzle opening (715).

[0014] Furthermore, the ejector increases the refrigerant pressure at the refrigerant outlet to a level higher than the refrigerant pressure at the refrigerant suction port through the action of shock waves.

[0015] According to this, the ejector (70) raises the refrigerant pressure at the refrigerant outlet (723) above the refrigerant pressure at the refrigerant suction port (721). Therefore, the suction refrigerant pressure (Ps) of the suction refrigerant drawn into the compressor (11) can be increased without using the heat generated by the compression work of the compressor (11) to raise the temperature of the refrigerant. As a result, the heating section (12, 121, 60) can quickly exert sufficient heating capacity.

[0016] The symbols in parentheses next to each means described in this section and in the claims are merely examples indicating the correspondence with the specific means described in the embodiments described later. [BRIEF DESCRIPTION OF THE DRAWINGS]

[0017] [Figure 1] Fig. 1 is a schematic overall configuration diagram of the vehicle air conditioner according to the first embodiment. [Figure 2] Fig. 2 is a cross-sectional view of the ejector according to the first embodiment. [Figure 3] Fig. 3 is a schematic configuration diagram of the indoor air conditioning unit according to the first embodiment. [Figure 4] Fig. 4 is a block diagram showing an electric control unit of the vehicle air conditioner according to the first embodiment. [Figure 5] Fig. 5 is a schematic overall configuration diagram showing the flow of refrigerant and heat medium in the cooling mode and the like of the vehicle air conditioner according to the first embodiment. [Figure 6] Fig. 6 is a Mollier diagram showing changes in the state of refrigerant in the cooling mode of the heat pump cycle according to the first embodiment. [Figure 7] Fig. 7 is a schematic overall configuration diagram showing the flow of refrigerant and heat medium in the outdoor air heat absorption heating mode and the like of the vehicle air conditioner according to the first embodiment. [Figure 8] Fig. 8 is a Mollier diagram showing changes in the state of refrigerant in the outdoor air heat absorption heating mode of the heat pump cycle according to the first embodiment. [Figure 9] Fig. 9 is a schematic overall configuration diagram showing the flow of refrigerant and heat medium in the outdoor air heat absorption parallel dehumidification heating mode and the like of the vehicle air conditioner according to the first embodiment. [Figure 10] Fig. 10 is a Mollier diagram showing changes in the state of refrigerant in the outdoor air heat absorption parallel dehumidification heating mode of the heat pump cycle according to the first embodiment. [Figure 11] Fig. 11 is a schematic overall configuration diagram showing the flow of refrigerant and heat medium in the battery independent cooling mode of the vehicle air conditioner according to the first embodiment. [Figure 12] Fig. 12 is a Mollier diagram showing changes in the state of refrigerant in the battery independent cooling mode of the heat pump cycle according to the first embodiment. [Figure 13] Fig. 13 is a Mollier diagram showing changes in the state of refrigerant in the cooling + battery cooling mode of the heat pump cycle according to the first embodiment. [Figure 14] This is a Mollier diagram showing the change in the state of the refrigerant in the outside air heat absorption and waste heat heating mode of the heat pump cycle of the first embodiment. [Figure 15] This is a Mollier diagram showing the change in the state of the refrigerant in the outside air heat absorption and waste heat parallel dehumidification heating mode of the heat pump cycle of the first embodiment. [Figure 16] This is a schematic overall diagram showing the flow of refrigerant and heat transfer medium in the evaporator-only dehumidifying and heating mode of the vehicle air conditioning system according to the first embodiment. [Figure 17] This is a Mollier diagram showing the change in the state of the refrigerant in the evaporator-only dehumidifying heating mode of the heat pump cycle of the first embodiment. [Figure 18] This is a schematic overall diagram showing the flow of refrigerant and heat transfer medium in the waste heat heating mode of the vehicle air conditioning system according to the first embodiment. [Figure 19] This is a Mollier diagram showing the change in the state of the refrigerant in the waste heat heating mode of the heat pump cycle of the first embodiment. [Figure 20] This is a schematic overall configuration diagram showing the flow of refrigerant and heat transfer medium in the waste heat parallel dehumidification heating mode of the vehicle air conditioning system according to the first embodiment. [Figure 21] This is a Mollier diagram showing the change in the state of the refrigerant in the waste heat parallel dehumidification heating mode of the heat pump cycle of the first embodiment. [Figure 22] This is an explanatory diagram illustrating the expansion wave and shock wave in the mixing section when the ejector of the first embodiment is used in suction mode. [Figure 23] This is an explanatory diagram showing the pressure change inside the ejector when the ejector of the first embodiment is used in suction mode. [Figure 24] This Mollier diagram shows the change in the state of the refrigerant in the heat pump cycle when the ejector of the first embodiment is used in suction mode. [Figure 25] This is an explanatory diagram illustrating the form of the shock wave generated under the first operating conditions of the ejector in the first embodiment. [Figure 26]This is an explanatory diagram illustrating the form of the shock wave generated under the second operating conditions of the ejector in the first embodiment. [Figure 27] This is an explanatory diagram illustrating the form of the shock wave generated under the third operating condition of the ejector in the first embodiment. [Figure 28] This is an explanatory diagram illustrating the form of the shock wave generated under the fourth operating condition of the ejector in the first embodiment. [Figure 29] This is an explanatory diagram illustrating the pressure change within the mixing section under the fourth operating condition of the ejector in the first embodiment. [Figure 30] This is an explanatory diagram illustrating the distance of the mixing section required to eliminate the pseudo-shock wave in the ejector of the first embodiment. [Figure 31] This is a schematic overall diagram showing the refrigerant flow in the hot gas start mode of the vehicle air conditioning system according to the first embodiment. [Figure 32] This is a Mollier diagram illustrating the pressurization action of the heat pump cycle in the hot gas startup mode of the first embodiment. [Figure 33] This is a schematic overall diagram showing the flow of refrigerant in the hot gas heating mode, etc., of the vehicle air conditioning system according to the first embodiment. [Figure 34] This is a Mollier diagram showing the change in the state of the refrigerant in the hot gas heating mode of the heat pump cycle of the first embodiment. [Figure 35] This is a Mollier diagram showing the change in the state of the refrigerant in the hot gas waste heat heating mode of the heat pump cycle of the first embodiment. [Figure 36] This is a schematic overall diagram showing the refrigerant flow in the hot gas outside air heat absorption heating mode of the vehicle air conditioning system according to the first embodiment. [Figure 37] This is a Mollier diagram showing the change in the state of the refrigerant in the hot gas outside air absorption heating mode of the heat pump cycle of the first embodiment. [Figure 38] This is a schematic overall configuration diagram showing the refrigerant flow in the hot gas parallel dehumidification heating mode of the vehicle air conditioning system according to the first embodiment. [Figure 39] This is a Mollier diagram showing the change in the state of the refrigerant in the hot gas parallel dehumidification heating mode of the heat pump cycle of the first embodiment. [Figure 40] This is a schematic overall diagram showing the refrigerant flow in the hot gas defrosting and heating mode of the vehicle air conditioning system according to the first embodiment. [Figure 41] This is a Mollier diagram showing the change in the state of the refrigerant in the hot gas defrost heating mode of the heat pump cycle of the first embodiment. [Figure 42] This is a schematic overall configuration diagram of a vehicle air conditioning system according to the second embodiment. [Figure 43] This is a cross-sectional view of the ejector according to the second embodiment. [Figure 44] This is a schematic overall configuration diagram of a vehicle air conditioning system according to the third embodiment. [Figure 45] This is a schematic overall configuration diagram of a vehicle air conditioning system according to the fourth embodiment. [Figure 46] This is a schematic overall configuration diagram of a vehicle air conditioning system according to the fifth embodiment. [Figure 47] This is a schematic overall configuration diagram of a vehicle air conditioning system according to the sixth embodiment. [Figure 48] This is a schematic overall configuration diagram of the vehicle air conditioning system according to the seventh embodiment. [Figure 49] This is a schematic overall configuration diagram of the vehicle air conditioning system according to the eighth embodiment. [Figure 50] This is a schematic overall diagram showing the refrigerant flow in the hot gas outside air intake heating mode of the vehicle air conditioning system according to the ninth embodiment. [Figure 51] This is a Mollier diagram showing the change in the state of the refrigerant in the hot gas outside air absorption heating mode of the heat pump cycle of the ninth embodiment. [Modes for carrying out the invention]

[0018] Several embodiments for carrying out the present invention will be described below with reference to the drawings. In each embodiment, parts corresponding to matters described in a prior embodiment will be denoted by the same reference numerals, and redundant descriptions may be omitted. If only a part of the configuration is described in each embodiment, other parts of the configuration can be applied to other embodiments described in advance. Not only can parts that are explicitly shown to be combinable in each embodiment be combined, but embodiments can also be partially combined even if not explicitly shown, as long as there is no particular impediment to the combination.

[0019] (First Embodiment) A first embodiment of the heat pump cycle device according to the present invention will be described using Figures 1 to 41. In this embodiment, the heat pump cycle device according to the present invention is applied to a vehicle air conditioning system 1 installed in an electric vehicle. The vehicle air conditioning system 1 provides air conditioning to the vehicle interior, which is the space to be air-conditioned, and also adjusts the temperature of various in-vehicle equipment that generates heat during operation. Therefore, the vehicle air conditioning system 1 is an air conditioning system with an in-vehicle equipment temperature adjustment function.

[0020] The vehicle air conditioning system 1 controls the temperature of the battery 80 and the high-voltage equipment 81 as on-board equipment. The battery 80 is a secondary battery that stores power supplied to multiple on-board equipment that operates electrically. The battery 80 is a battery pack formed by electrically connecting multiple stacked battery cells in series or parallel. The battery cells in this embodiment are lithium-ion batteries.

[0021] The battery 80 generates heat during operation (i.e., during charging and discharging). The battery 80 tends to lose output at low temperatures and deteriorates quickly at high temperatures. Therefore, the temperature of the battery 80 needs to be maintained within an appropriate temperature range (in this embodiment, 15°C or higher and 55°C or lower).

[0022] The high-voltage electrical equipment 81 is an in-vehicle device that operates when power is supplied and generates heat during operation. Specifically, the high-voltage electrical equipment 81 in this embodiment is a power control unit that performs substation and power distribution. When the high-voltage electrical equipment 81 is exposed to high temperatures, the electrical circuits deteriorate. Therefore, the high-voltage electrical equipment 81 needs to be maintained at a temperature lower than the standard heat resistance temperature (130°C in this embodiment) that can protect the electrical circuits.

[0023] In other words, the vehicle air conditioning system 1 controls the temperature of multiple in-vehicle devices that have different heat resistance temperatures. Specifically, the upper limit temperature of the battery 80 is lower than the standard heat resistance temperature of the high-voltage electrical equipment 81.

[0024] The vehicle air conditioning system 1 includes a heat pump cycle 10, a low-temperature heat transfer medium circuit 30, an indoor air conditioning unit 40, a control device 50, and the like.

[0025] First, the heat pump cycle 10 will be explained using the overall configuration diagram in Figure 1. The heat pump cycle 10 is a vapor compression type refrigeration cycle that adjusts the temperature of the air supplied to the vehicle cabin and the low-temperature heat transfer medium circulating in the low-temperature heat transfer medium circuit 30.

[0026] The heat pump cycle 10 is configured to allow switching of the refrigerant circuit according to various operating modes, as described later, in order to control the temperature of the air conditioning and onboard equipment inside the vehicle. The heat pump cycle 10 uses an HFO-type refrigerant (specifically, R1234yf) as the refrigerant. The heat pump cycle 10 constitutes a subcritical refrigeration cycle in which the pressure of the high-pressure side refrigerant does not exceed the critical pressure of the refrigerant.

[0027] The refrigerant is mixed with refrigeration oil for lubricating the compressor 11. The refrigeration oil is either PAG oil (i.e., polyalkylene glycol oil) or POE (i.e., polyol ester) which is compatible with the liquid phase refrigerant. A portion of the refrigeration oil circulates with the refrigerant in the heat pump cycle 10.

[0028] The compressor 11 in the heat pump cycle 10 draws in refrigerant, compresses it, and discharges it. The compressor 11 is an electric compressor in which a fixed-capacity compression mechanism with a fixed discharge capacity is rotationally driven by an electric motor. The rotational speed (i.e., refrigerant discharge capacity) of the compressor 11 is controlled by a control signal output from the control device 50, which will be described later.

[0029] The compressor 11 is located in the drive unit compartment, which is formed on the front side of the passenger compartment. The drive unit compartment forms a space in which at least some of the equipment used for generating and adjusting the driving force for vehicle operation (for example, a motor generator, which will be described later) is located.

[0030] The inlet side of the first three-way joint 13a is connected to the discharge port of the compressor 11. The first three-way joint 13a has three inlet and outlet ports that communicate with each other. The first three-way joint 13a can be a joint formed by joining multiple pipes, or a joint formed by providing multiple refrigerant passages in a metal block or resin block.

[0031] Furthermore, the heat pump cycle 10 is equipped with second three-way joints 13b to ninth three-way joints 13i, as will be described later. The basic configuration of the second three-way joints 13b to sixth three-way joints 13f is the same as that of the first three-way joint 13a. Also, the basic configuration of each three-way joint, which will be described in the embodiments described later, is the same as that of the first three-way joint 13a.

[0032] This type of three-way joint branches the refrigerant flow when one of the three inlets / outlets is used as an inlet and the other two as outlets. It also merges the refrigerant flows when two of the three inlets / outlets are used as inlets and the remaining one as an outlet. The first three-way joint 13a is an upstream branching section that branches the flow of discharged refrigerant discharged from the compressor 11.

[0033] One outlet of the first three-way joint 13a is connected to the refrigerant inlet side of the indoor condenser 12. The indoor condenser 12 is located inside the air conditioning case 41 of the indoor air conditioning unit 40, which will be described later. The indoor condenser 12 is a heat exchanger that exchanges heat between the discharged refrigerant flowing out from one outlet of the first three-way joint 13a and the blown air. The indoor condenser 12 is a heat dissipation unit that releases the heat contained in the discharged refrigerant into the blown air.

[0034] Therefore, the indoor condenser 12 is a heating unit that heats the blown air, which is the object to be heated, using the high-pressure refrigerant discharged from the compressor 11 as a heat source.

[0035] The inlet side of the second three-way joint 13b is connected to the refrigerant outlet of the indoor condenser 12. One outlet of the second three-way joint 13b is connected to one inlet side of the fifth three-way joint 13e. The outlet of the fifth three-way joint 13e is connected to the inlet side of the receiver 15. The refrigerant passage from the inlet of the second three-way joint 13b through the fifth three-way joint 13e to the inlet side of the receiver 15 is the inlet side passage 21a.

[0036] In the inlet passage 21a, a first on-off valve 14a is located in the refrigerant passage from the inlet of the second three-way joint 13b to one of the inlets of the fifth three-way joint 13e. The first on-off valve 14a is a solenoid valve that opens and closes the inlet passage 21a. The opening and closing operation of the first on-off valve 14a is controlled by a control voltage output from the control device 50.

[0037] Furthermore, the heat pump cycle 10 includes a second on-off valve 14b and a third on-off valve 14c, as will be described later. The basic configuration of the second on-off valve 14b and the third on-off valve 14c is the same as that of the first on-off valve 14a. The first on-off valves 14a to the third on-off valves 14c can switch the refrigerant circuit by opening and closing the refrigerant passage. Therefore, the first on-off valves 14a to the third on-off valves 14c constitute the refrigerant circuit switching section.

[0038] The receiver 15 is a high-pressure side gas-liquid separation unit that separates the gas-liquid of the high-pressure refrigerant that has flowed out of the heat exchanger, which functions as a condenser for condensing the refrigerant in the heat pump cycle 10. The receiver 15 is a high-pressure side liquid storage unit that allows a portion of the separated liquid-phase refrigerant to flow downstream and stores the remaining liquid-phase refrigerant as excess refrigerant in the cycle.

[0039] The outlet of receiver 15 is connected to the inlet side of the 7th three-way joint 13g. One outlet of the 7th three-way joint 13g is connected to one inlet side of the 3rd three-way joint 13c. The refrigerant passage from the outlet of receiver 15 through the 7th three-way joint 13g to one inlet of the 3rd three-way joint 13c is the outlet-side passage 21b.

[0040] In the outlet passage 21b, a first check valve 17a is placed in the refrigerant passage leading from one outlet of the seventh three-way joint 13g to one inlet of the third three-way joint 13c. The first check valve 17a allows refrigerant to flow from the seventh three-way joint 13g side to the third three-way joint 13c side, and prohibits refrigerant from flowing from the third three-way joint 13c side to the seventh three-way joint 13g side.

[0041] Furthermore, the other outlet of the second three-way joint 13b is connected to the other inlet side of the third three-way joint 13c. A second on-off valve 14b is positioned in the refrigerant passage leading from the other outlet of the second three-way joint 13b to the other inlet of the third three-way joint 13c. The second on-off valve 14b opens and closes the refrigerant passage leading from the other outlet of the second three-way joint 13b to the other inlet of the third three-way joint 13c.

[0042] The outlet of the third three-way joint 13c is connected to the inlet side of the heating flow control valve 16a. The heating flow control valve 16a is a heating flow control unit that adjusts the flow rate of refrigerant flowing out of the third three-way joint 13c and into the outdoor heat exchanger 18, such as during the outdoor air heat absorption heating mode described later. Furthermore, the heating flow control valve 16a is a heating pressure reducing unit that reduces the pressure of the refrigerant flowing out of the third three-way joint 13c and into the outdoor heat exchanger 18.

[0043] The heating flow control valve 16a is an electrically operated variable throttling mechanism having a valve body that changes the throttling opening and an electric actuator (specifically, a stepping motor or a brushless DC motor) as a drive unit that displaces the valve body. The operation of the heating flow control valve 16a is controlled by a control signal output from the control device 50.

[0044] Furthermore, the heating flow rate control valve 16a adjusts the flow rate of the refrigerant flowing out of the indoor condenser 12, which is the heating unit, to adjust the flow rate of the refrigerant flowing into the outdoor heat exchanger 18, such as during the hot gas outside air heat absorption heating mode described later. Therefore, the heating flow rate control valve 16a is included in the heating unit side flow rate control unit.

[0045] The heating flow control valve 16a has a fully open function that allows it to function as a simple refrigerant passage with almost no refrigerant pressure reduction or flow rate adjustment effect when the throttle opening is fully open. The heating flow control valve 16a also has a fully closed function that blocks the refrigerant passage when the throttle opening is fully closed.

[0046] Furthermore, the heat pump cycle 10 includes a cooling flow control valve 16b, a cooling flow control valve 16c, and a bypass flow control valve 16d, as will be described later. The basic configuration of the cooling flow control valve 16b, the cooling flow control valve 16c, and the bypass flow control valve 16d is the same as that of the heating flow control valve 16a.

[0047] The heating flow control valve 16a, the cooling flow control valve 16b, the cooling flow control valve 16c, and the bypass flow control valve 16d can switch the refrigerant circuit by exhibiting a fully closed function. Therefore, the heating flow control valve 16a to the bypass flow control valve 16d also function as a refrigerant circuit switching unit.

[0048] Of course, the heating flow control valve 16a to the bypass flow control valve 16d may be formed by combining a variable throttle mechanism that does not have a fully closing function with an on-off valve that opens and closes the throttle passage. In this case, each on-off valve becomes a refrigerant circuit switching section.

[0049] The outlet of the heating flow control valve 16a is connected to the refrigerant inlet side of the outdoor heat exchanger 18. The outdoor heat exchanger 18 is an outdoor heat exchange unit that exchanges heat between the refrigerant flowing out from the heating flow control valve 16a and outside air blown in from an outside air fan (not shown). The outdoor heat exchanger 18 is located at the very front of the drive unit compartment. Therefore, when the vehicle is running, the airflow entering the drive unit compartment through the grille can be directed onto the outdoor heat exchanger 18.

[0050] Furthermore, the outdoor heat exchanger 18 is included in the suction-side heat exchange unit, which, in the hot gas outside air intake heating mode described later, exchanges heat with the outside air, which is the object of heat exchange, and discharges the refrigerant that has flowed out from the heating unit side flow rate adjustment unit with the outside air, which is the object of heat exchange, to the refrigerant suction port 721 side of the ejector 70 described later.

[0051] The inlet side of the fourth three-way joint 13d is connected to the refrigerant outlet of the outdoor heat exchanger 18. The other inlet side of the fifth three-way joint 13e is connected to one outlet of the fourth three-way joint 13d. The other inlet side of the sixth three-way joint 13f is connected to the other outlet of the fourth three-way joint 13d.

[0052] A second check valve 17b is positioned in the refrigerant passage leading from one outlet of the fourth three-way joint 13d to the other inlet of the fifth three-way joint 13e. The second check valve 17b allows refrigerant to flow from the fourth three-way joint 13d side to the fifth three-way joint 13e side, and prevents refrigerant from flowing from the fifth three-way joint 13e side to the fourth three-way joint 13d side.

[0053] A third on-off valve 14c and a third check valve 17c are arranged in the refrigerant passage from the other outlet of the fourth three-way joint 13d to one inlet of the sixth three-way joint 13f. The third on-off valve 14c opens and closes the refrigerant passage from the other outlet of the fourth three-way joint 13d to one inlet of the sixth three-way joint 13f. The third check valve 17c allows refrigerant to flow from the third on-off valve 14c side to the sixth three-way joint 13f side, and prevents refrigerant from flowing from the sixth three-way joint 13f side to the third on-off valve 14c side.

[0054] Furthermore, the inlet side of the 8th three-way joint 13h is connected to the other outlet of the 7th three-way joint 13g located in the outlet passage 21b. The inlet side of the cooling flow control valve 16b is connected to one outlet of the 8th three-way joint 13h. The inlet side of the cooling flow control valve 16c is connected to the other outlet of the 8th three-way joint 13h.

[0055] The cooling flow rate control valve 16b is a cooling flow rate control unit that adjusts the flow rate of refrigerant flowing out from the eighth three-way joint 13h and into the indoor evaporator 19, as described later, during the cooling mode. Furthermore, the cooling flow rate control valve 16b is a cooling pressure reduction unit that reduces the pressure of the refrigerant flowing out from the eighth three-way joint 13h and into the indoor evaporator 19.

[0056] Furthermore, the cooling flow rate control valve 16b adjusts the flow rate of refrigerant flowing out of the indoor condenser 12, which is the heating unit, to adjust the flow rate of refrigerant flowing into the indoor evaporator 19, such as during the hot gas parallel dehumidification heating mode described later. Therefore, the cooling flow rate control valve 16b is included in the heating unit side flow rate control unit.

[0057] The outlet of the cooling flow control valve 16b is connected to the refrigerant inlet side of the indoor evaporator 19. The indoor evaporator 19 is a heat exchange unit for cooling that exchanges heat between the low-pressure refrigerant, which has been reduced in pressure by the cooling flow control valve 16b, and the air blown from the indoor blower 42 into the vehicle interior. The indoor evaporator 19 cools the blown air by evaporating the low-pressure refrigerant and exerting an endothermic effect.

[0058] The indoor evaporator 19 is located inside the air conditioning case 41 of the indoor air conditioning unit 40. The indoor evaporator 19 is also included in the suction-side heat exchange section, which, in the hot gas parallel dehumidification heating mode described later, exchanges heat between the refrigerant flowing out from the heating section side flow rate adjustment section and the blown air, which is the object of heat exchange, and flows out to the refrigerant suction port 721 side of the ejector 70. One inlet of the ninth three-way joint 13i is connected to the refrigerant outlet of the indoor evaporator 19.

[0059] The cooling flow rate control valve 16c is a cooling flow rate control unit that adjusts the flow rate of refrigerant flowing out of the 8th three-way joint 13h and into the chiller 20 during hot gas heating mode, cooling operation mode, etc., as described later. Furthermore, the cooling flow rate control valve 16c is a cooling pressure reduction unit that reduces the pressure of the refrigerant flowing out of the 8th three-way joint 13h and into the chiller 20.

[0060] Furthermore, the cooling flow rate control valve 16c adjusts the flow rate of refrigerant flowing out of the indoor condenser 12, which is the heating unit, to adjust the flow rate of refrigerant flowing into the chiller 20, such as during the hot gas heating mode described later. Therefore, the cooling flow rate control valve 16c is included in the heating unit side flow rate control unit.

[0061] The outlet of the cooling flow control valve 16c is connected to the inlet side of the refrigerant passage of the chiller 20. The chiller 20 is a heat exchange unit for cooling that exchanges heat between the low-pressure refrigerant, which has been reduced in pressure by the cooling flow control valve 16c, and the low-temperature heat transfer medium circulating in the low-temperature heat transfer medium circuit 30. The chiller 20 cools the low-temperature heat transfer medium by evaporating the low-pressure refrigerant and exerting an endothermic effect.

[0062] The chiller 20 is located in the drive unit room along with the compressor 11 and the like. The chiller 20 is also included in the suction-side heat exchange section, which, in the hot gas parallel dehumidification heating mode described later, exchanges heat with the low-temperature side heat transfer medium, which is the object to be heat exchanged, and discharges it to the refrigerant suction port 721 of the ejector 70. The other inlet of the ninth three-way joint 13i is connected to the outlet of the refrigerant passage of the chiller 20.

[0063] The outlet of the ninth three-way joint 13i is connected to the other inlet side of the sixth three-way joint 13f. A fourth check valve 17d is positioned in the refrigerant passage from the outlet of the ninth three-way joint 13i to the other inlet side of the sixth three-way joint 13f. The fourth check valve 17d allows refrigerant to flow from the ninth three-way joint 13i side to the sixth three-way joint 13f side, and prevents refrigerant from flowing from the sixth three-way joint 13f side to the ninth three-way joint 13i side.

[0064] The outlet of the sixth three-way joint 13f is connected to the refrigerant suction port 721 formed in the body portion 72 of the ejector 70.

[0065] Furthermore, the inlet side of the bypass flow control valve 16d is connected to the other outlet of the first three-way joint 13a, which is connected to the discharge port of the compressor 11. The nozzle portion 71 side of the ejector 70 is connected to the outlet of the bypass flow control valve 16d.

[0066] The refrigerant passage from the other outlet of the first three-way joint 13a to the nozzle portion 71 of the ejector 70 is a bypass passage 21c that allows the other refrigerant, which was branched off at the first three-way joint 13a which is the upstream branching section, to flow around the indoor condenser 12 which is the heating section.

[0067] The bypass-side flow control valve 16d is a bypass-side flow control unit that adjusts the flow rate of refrigerant flowing through the bypass passage 21c and into the nozzle section 71 of the ejector 70, such as during the hot gas heating mode described later. Furthermore, the bypass-side flow control valve 16d is a bypass-side pressure reducing unit that reduces the pressure of the refrigerant flowing out from the first three-way joint 13a and into the nozzle section 71 of the ejector 70.

[0068] The ejector 70 is a refrigerant acceleration unit that accelerates and injects the refrigerant at the nozzle section 71. The ejector 70 is a refrigerant transport unit that sucks in and transports the refrigerant from the refrigerant suction port 721 by the action of the injected refrigerant. The ejector 70 is a refrigerant pressurization unit that increases the pressure of the refrigerant that has flowed into the interior by the action of the injected refrigerant. The detailed configuration of the ejector 70 will be explained using Figure 2. The ejector 70 has a nozzle section 71 and a body section 72.

[0069] The nozzle section 71 accelerates the refrigerant that has flowed inside to supersonic speed and injects it into the mixing and pressurizing section 722 formed inside the body section 72. The nozzle section 71 is formed by plastic deformation or cutting of a cylindrical member made of metal (stainless steel in this embodiment).

[0070] At the uppermost part of the refrigerant passage of the nozzle section 71, a nozzle inlet 711 is formed to allow refrigerant that has flowed out from the bypass passage 21c to flow in. At the lowermost part of the refrigerant flow of the nozzle section 71, an injection port 715 is formed to inject refrigerant.

[0071] The refrigerant passage of the nozzle section 71 has a narrow tip section 712, a throat section 713, and a widening section 714. The narrow tip section 712 is the part that reduces the cross-sectional area of ​​the refrigerant passage as it moves downstream from the nozzle inlet 711. The throat section 713 is the part that reduces the cross-sectional area of ​​the refrigerant passage the most. The widening section 714 is the part that increases the cross-sectional area of ​​the refrigerant passage as it moves from the throat section 713 towards the nozzle opening 715.

[0072] In other words, the ejector 70 employs a so-called Laval nozzle as the nozzle section 71. The nozzle section 71 of this embodiment can accelerate the refrigerant injected from the injection port 715 to a speed exceeding the speed of sound at a first pressure reduction ratio (Pnout / Pin) that can obtain a predetermined adiabatic enthalpy drop Δh. Here, Pin is the inlet pressure of the refrigerant at the nozzle inlet 711, and Pnout is the injection port pressure of the refrigerant at the injection port 715.

[0073] The body portion 72 is a cylindrical member that forms the outer shell of the ejector 70 and also forms a refrigerant passage inside. The nozzle portion 71 is fixed to the inside of the body portion 72 at one end in the longitudinal direction by means of press-fitting or screw fastening. The central axis of the refrigerant passage of the nozzle portion 71 and the central axis of the refrigerant passage of the body portion 72 are arranged coaxially. The body portion 72 may be made of metal (specifically, aluminum alloy) or resin.

[0074] The body section 72 has a refrigerant suction port 721, a mixing and pressurizing section 722, a refrigerant outlet 723, etc. The refrigerant suction port 721 is formed on the outer circumference side of the nozzle section 71 on the cylindrical side surface of the body section 72. The refrigerant suction port 721 is a through-hole that draws the refrigerant that has flowed out from the sixth three-way joint 13f as suction refrigerant into the inside of the ejector 70 due to the action of the refrigerant sprayed from the nozzle section 71.

[0075] The mixing and pressurizing section 722 is a refrigerant passage for mixing the injected refrigerant and the suctioned refrigerant and increasing the pressure. The mixing and pressurizing section 722 is broadly divided into a mixing section 722a and an area expansion section 722b.

[0076] The mixing section 722a is the part where the mixed refrigerant, which is a mixture of the injected refrigerant and the suctioned refrigerant, is pressurized to approach an equilibrium state.

[0077] Here, equilibrium means a state in which there is almost no temperature distribution, pressure distribution, or flow velocity distribution in the mixed refrigerant. If the mixed refrigerant is a gas-liquid two-phase refrigerant, it means a state in which the droplets are uniformly distributed in the gas phase refrigerant, and the temperature, pressure, and flow velocity of the gas phase refrigerant and droplets in the gas-liquid two-phase refrigerant are generally uniform. If the mixed refrigerant is a gas phase refrigerant, it means a state in which the temperature, pressure, and flow velocity of the gas phase refrigerant are generally uniform.

[0078] However, even in equilibrium, a velocity distribution following a power law will occur in the turbulent boundary layer on the outer wall side of the mixing space 722a.

[0079] The mixing section 722a forms a cylindrical space. Therefore, the refrigerant passage cross-sectional area is constant in the mixing section 722a. Furthermore, in the ejector 70 of this embodiment, when the length of the mixing section 722a in the central axis direction (hereinafter referred to as the Z-axis direction) is defined as the mixing section distance L, the mixing section distance L is set to satisfy the following equations F1 and F2.

[0080]

number

[0081]

number

[0082] u0 is the average mass flow velocity of the refrigerant in the Z-axis direction at the inlet of the mixing section 722a during the operating mode in which the ejector 70 draws in gas-liquid two-phase refrigerant from the refrigerant suction port 721.

[0083] ρ l This is the density of liquid-phase refrigerant particles (hereinafter referred to as droplets) in the mixed refrigerant at the inlet of the mixing section 722a during the operating mode in which the ejector 70 draws in a gas-liquid two-phase refrigerant from the refrigerant suction port 721.

[0084] D l This is the average diameter of the droplets at the inlet of the mixing section 722a during the operating mode in which the ejector 70 draws in a gas-liquid two-phase refrigerant from the refrigerant suction port 721.

[0085] μ g This is the viscosity of the gaseous phase refrigerant in the mixed refrigerant at the inlet of the mixing section 722a during the operating mode in which the ejector 70 draws in gaseous two-phase refrigerant from the refrigerant suction port 721.

[0086] Lv is the distance obtained by integrating the average mass flow velocity U0 of the mixed refrigerant at the inlet of the mixing and pressurizing unit 722 with a dimensionless relaxation number represented by the ratio of the inertial force to the viscosity of the droplets, and is called the relaxation distance. The relaxation distance Lv represents the distance obtained by integrating the initial velocity of the mixed refrigerant at the inlet of the mixing and pressurizing unit 722 with the time it takes for the flow velocity of the gaseous refrigerant in the mixed refrigerant to become equal to the flow velocity of the droplets.

[0087] Therefore, in order to bring the mixed refrigerant of the injected refrigerant and the suctioned refrigerant flowing out of the mixing section 722a to equilibrium, the mixing section distance L must be at least longer than the relaxation distance Lv.

[0088] The area-expanding section 722b is a part that expands the cross-sectional area of ​​the refrigerant passage in the direction of flow, connecting the downstream end of the mixing section 722a to the refrigerant outlet 723. The suction port side of the compressor 11 is connected to the refrigerant outlet 723 of the ejector 70.

[0089] The ejector 70 in this embodiment changes its usage mode depending on the refrigerant circuit configuration of the heat pump cycle 10. There are three types of usage modes for the ejector 70: (α) passage mode, (β) nozzle mode, and (γ) suction mode.

[0090] (α) The passage mode is a mode of use in which the refrigerant that has been introduced from the refrigerant suction port 721 to the mixing and pressurizing unit 722 is discharged from the refrigerant outlet 723 without introducing the refrigerant into the nozzle portion 71 of the ejector 70.

[0091] In passage mode, refrigerant is not allowed to flow into the nozzle section 71, so the ejector 70 does not perform refrigerant suction or refrigerant pressurization. Therefore, in passage mode, the ejector 70 functions as a refrigerant passage that guides the refrigerant flowing in from the refrigerant suction port 721 to the refrigerant outlet 723 via the mixing and pressurization section 722.

[0092] (β) Nozzle mode is a mode of use in which refrigerant is introduced into the nozzle portion 71 of the ejector 70, and the refrigerant flow path communicating with the refrigerant suction port 721 is blocked. In other words, nozzle mode is a mode of use in which refrigerant is introduced into the nozzle portion 71 of the ejector 70, and the suction of refrigerant from the refrigerant suction port 721 is suppressed or limited. Alternatively, nozzle mode is a mode of use in which refrigerant is introduced into the nozzle portion 71 of the ejector 70, and the suction of refrigerant from the refrigerant suction port 721 is substantially prohibited.

[0093] (γ) The suction mode is a mode of use in which refrigerant is introduced into the nozzle portion 71 of the ejector 70 and refrigerant is drawn in from the refrigerant suction port 721.

[0094] The functions of the ejector 70 in (β) nozzle mode and (γ) suction mode will be described later.

[0095] Next, the low-temperature side heat transfer medium circuit 30 will be described. The low-temperature side heat transfer medium circuit 30 is a circuit that circulates the low-temperature side heat transfer medium. In this embodiment, an aqueous solution of ethylene glycol is used as the low-temperature side heat transfer medium. As shown in Figure 1, the low-temperature side heat transfer medium circuit 30 is equipped with a low-temperature side heat transfer medium pump 31, a heat transfer medium passage for the chiller 20, a cooling water passage 80a for the battery 80, a cooling water passage 81a for the high-voltage equipment 81, a low-temperature side radiator 32, and the like.

[0096] The low-temperature side heat transfer pump 31 is a low-temperature side heat transfer fluid pumping unit that draws in the low-temperature side heat transfer fluid and pumps it into the heat transfer fluid passage of the chiller 20. The low-temperature side heat transfer fluid pump 31 is an electric water pump whose rotational speed (i.e., pumping capacity) is controlled by a control voltage output from the control device 50.

[0097] The outlet of the heat transfer medium passage of the chiller 20 is connected to the inlet of the first heat transfer medium three-way joint 33a. The basic configuration of the first heat transfer medium three-way joint 33a is the same as that of the first three-way joint 13a for the refrigerant.

[0098] Furthermore, the low-temperature side heat transfer fluid circuit 30 is equipped with a second heat transfer fluid three-way joint 33b to a fourth heat transfer fluid three-way joint 33d. The basic configuration of the second heat transfer fluid three-way joint 33b to the fourth heat transfer fluid three-way joint 33d is the same as that of the first heat transfer fluid three-way joint 33a. Also, the basic configuration of each heat transfer fluid three-way joint, which will be described in the embodiments described later, is the same as that of the first heat transfer fluid three-way joint 33a.

[0099] The inlet side of the first heat transfer medium flow control valve 36a is connected to one outlet of the first heat transfer medium three-way joint 33a. The basic configuration of the first heat transfer medium flow control valve 36a is the same as that of the cooling flow control valve 16b for refrigerants, etc. The first heat transfer medium flow control valve 36a has a fully open function and a fully closed function.

[0100] Furthermore, the low-temperature side heat transfer fluid circuit 30 is equipped with a second heat transfer fluid flow rate control valve 36b and a third heat transfer fluid flow rate control valve 36c. The basic configuration of the second heat transfer fluid flow rate control valve 36b and the third heat transfer fluid flow rate control valve 36c is the same as that of the first heat transfer fluid flow rate control valve 36a. Also, the basic configuration of each heat transfer fluid flow rate control valve, which will be described in the embodiments described later, is the same as that of the first heat transfer fluid flow rate control valve 36a.

[0101] The first to third heat transfer fluid flow control valves 36a to 36c can switch the heat transfer fluid circuit by exhibiting a fully closed function. Therefore, the first to third heat transfer fluid flow control valves 36a to 36c also function as a heat transfer fluid circuit switching unit.

[0102] Of course, similar to the cooling flow control valve 16b, the first to third heat transfer fluid flow control valves 36a to 36c may be formed by combining a variable throttle mechanism that does not have a fully closing function with an on-off valve that opens and closes the heat transfer fluid passage. In this case, each on-off valve becomes a heat transfer fluid circuit switching section.

[0103] The outlet of the first heat transfer medium flow control valve 36a is connected to the inlet side of the cooling water passage 80a of the battery 80. The cooling water passage 80a of the battery 80 is a heat transfer medium passage for cooling the battery 80 by circulating the heat transfer medium that has flowed out from the chiller 20. In other words, the cooling water passage 80a is a heat exchange passage that cools the battery 80 by exchanging heat between the heat transfer medium circulating in the heat transfer medium passage and the battery cells.

[0104] The cooling water passage 80a is formed inside a battery-specific case that houses multiple stacked battery cells. The passage configuration of the cooling water passage 80a is such that multiple passages are connected in parallel inside the battery-specific case. This allows all battery cells to be cooled evenly in the cooling water passage 80a. One inlet side of the fourth heat transfer fluid three-way joint 33d is connected to the outlet of the cooling water passage 80a of the battery 80.

[0105] Furthermore, the inlet side of the second heat transfer medium three-way joint 33b is connected to the other outlet of the first heat transfer medium three-way joint 33a. The inlet side of the second heat transfer medium flow rate control valve 36b is connected to one outlet of the second heat transfer medium three-way joint 33b. The inlet side of the third heat transfer medium flow rate control valve 36c is connected to the other outlet of the second heat transfer medium three-way joint 33b.

[0106] The outlet of the second heat transfer medium flow rate control valve 36b is connected to the inlet side of the cooling water passage 81a of the power electrical equipment 81. The cooling water passage 81a of the power electrical equipment 81 is a heat transfer medium passage for cooling the power electrical equipment 81 by circulating the heat transfer medium that has flowed out from the chiller 20. In other words, the cooling water passage 81a is a heat exchange passage that cools the power electrical equipment 81 by exchanging heat between the heat transfer medium circulating in the heat transfer medium passage and the power electrical equipment 81.

[0107] One inlet side of the third heat transfer fluid three-way joint 33c is connected to the outlet of the cooling water passage 81a of the high-voltage electrical equipment 81.

[0108] The outlet of the third heat transfer medium flow control valve 36c is connected to the heat transfer medium inlet side of the low-temperature side radiator 32. The low-temperature side radiator 32 is a heat transfer medium and outside air heat exchange unit that exchanges heat between the low-temperature side heat transfer medium and outside air blown by an outside air fan (not shown).

[0109] The low-temperature side radiator 32 is located on the front side of the drive unit compartment. Therefore, when the vehicle is running, the airflow can be directed towards the low-temperature side radiator 32. The low-temperature side radiator 32 may be integrally formed with the outdoor heat exchanger 18.

[0110] The outlet of the low-temperature side radiator 32 is connected to the other inlet side of the third heat transfer medium three-way joint 33c. The outlet of the third heat transfer medium three-way joint 33c is connected to the other inlet side of the fourth heat transfer medium three-way joint 33d. The outlet of the fourth heat transfer medium three-way joint 33d is connected to the suction side of the low-temperature side heat transfer medium pump 31.

[0111] Next, the interior air conditioning unit 40 will be described. The interior air conditioning unit 40 is a unit that integrates multiple components to blow air adjusted to an appropriate temperature for air conditioning inside the vehicle into the appropriate location inside the vehicle. The interior air conditioning unit 40 is located inside the instrument panel at the very front of the vehicle interior.

[0112] As shown in Figure 3, the indoor air conditioning unit 40 has an air conditioning case 41 that forms an air passage for supplied air. The air passage formed within the air conditioning case 41 houses an indoor blower 42, an indoor evaporator 19, an indoor condenser 12, and the like. The air conditioning case 41 is made of a resin (specifically, polypropylene) that has a certain degree of elasticity and excellent strength.

[0113] An internal / external air switching device 43 is located at the upstream end of the airflow path of the air conditioning case 41. The internal / external air switching device 43 switches between introducing internal air (i.e., air from inside the vehicle) and external air (i.e., air from outside the vehicle) into the air conditioning case 41. The operation of the internal / external air switching device 43 is controlled by a control signal output from the control device 50.

[0114] An interior blower 42 is positioned downstream of the airflow from the interior / exterior air switching device 43. The interior blower 42 is a blower that directs the air drawn in via the interior / exterior air switching device 43 into the vehicle interior. The rotational speed (i.e., blowing capacity) of the interior blower 42 is controlled by a control voltage output from the control device 50.

[0115] An indoor evaporator 19 and an indoor condenser 12 are located downstream of the airflow from the indoor blower 42. The indoor evaporator 19 is located upstream of the indoor condenser 12. Inside the air conditioning case 41, a cold air bypass passage 45 is formed to allow the airflow that has passed through the indoor evaporator 19 to bypass the indoor condenser 12.

[0116] An air mix door 44 is located downstream of the airflow of the indoor evaporator 19 inside the air conditioning case 41, and upstream of the airflow of the indoor condenser 12 and the cold air bypass passage 45.

[0117] The air mix door 44 adjusts the ratio of the airflow rate of the air that passes through the air passage where the indoor condenser 12 is located and the airflow rate of the air that passes through the cold air bypass passage 45, from the airflow that has passed through the indoor evaporator 19. The operation of the actuator for driving the air mix door 44 is controlled by a control signal output from the control device 50.

[0118] A mixing space 46 is located downstream of the indoor condenser 12 and the cold air bypass passage 45. The mixing space 46 is a space where the air heated in the indoor condenser 12 is mixed with the air that has passed through the cold air bypass passage 45 and has not been heated.

[0119] Therefore, the indoor air conditioning unit 40 can adjust the temperature of the air (i.e., conditioned air) that is mixed in the mixing space 46 and blown into the passenger compartment by adjusting the opening of the air mix door 44. The air mix door 44 is a heat exchange airflow adjustment unit that adjusts the airflow rate of the air that is heat-exchanged in the indoor condenser 12.

[0120] At the downstream end of the airflow path of the air conditioning case 41, there are multiple openings (not shown) for blowing conditioned air to various locations inside the vehicle. Each of these openings is equipped with a blow-out mode door (not shown) that opens and closes it. The operation of the actuators for driving the blow-out mode doors is controlled by a control signal output from the control device 50.

[0121] Therefore, the interior air conditioning unit 40 can blow conditioned air at the appropriate temperature to the appropriate location in the vehicle interior by switching the opening of the air outlet mode door.

[0122] Next, the electrical control unit of the vehicle air conditioning system 1 will be described. The control unit 50 has a well-known microcomputer including a CPU, ROM, RAM, etc., and its peripheral circuits. The control unit 50 performs various calculations and processes based on the control program stored in the ROM. Then, based on the calculation and processing results, the control unit 50 controls the operation of various controlled devices connected to the output side.

[0123] As shown in the block diagram in Figure 4, various control sensors are connected to the input side of the control device 50. The control sensors include an indoor temperature sensor 51a, an outdoor temperature sensor 51b, a solar radiation sensor 51c, a discharge pressure sensor 52a, a high-pressure sensor 52b, a high-pressure temperature sensor 52c, an outdoor unit pressure sensor 52d, an outdoor unit temperature sensor 52e, an evaporator pressure sensor 52f, an evaporator temperature sensor 52g, an intake pressure sensor 52h, an intake temperature sensor 52i, a battery coolant temperature sensor 53a, an equipment coolant temperature sensor 53b, a battery temperature sensor 54, an air conditioning air temperature sensor 55, and the like.

[0124] The interior temperature sensor 51a is an interior temperature detection unit that detects the temperature inside the vehicle (interior temperature) Tr. The exterior temperature sensor 51b is an exterior temperature detection unit that detects the temperature outside the vehicle (outside temperature) Tam. The solar radiation sensor 51c is a solar radiation detection unit that detects the amount of solar radiation As irradiated into the vehicle interior.

[0125] The discharge pressure sensor 52a is a discharge pressure detection unit that detects the discharge refrigerant pressure Pd, which is the pressure of the refrigerant discharged from the compressor 11. The high-pressure pressure sensor 52b is a high-pressure pressure detection unit that detects the high-pressure side refrigerant pressure P1, which is the pressure of the refrigerant on the outlet side of the indoor condenser 12. The high-pressure temperature sensor 52c is a high-pressure temperature detection unit that detects the high-pressure side refrigerant temperature T1, which is the temperature of the refrigerant on the outlet side of the indoor condenser 12.

[0126] The outdoor unit pressure sensor 52d is an outdoor unit pressure detection unit that detects the outdoor unit side refrigerant pressure P2, which is the pressure of the refrigerant in the outdoor heat exchanger 18. More specifically, the outdoor unit pressure sensor 52d in this embodiment detects the pressure of the refrigerant on the outlet side of the outdoor heat exchanger 18.

[0127] The outdoor unit temperature sensor 52e is an outdoor unit temperature detection unit that detects the outdoor unit side refrigerant temperature T2, which is the temperature of the refrigerant in the outdoor heat exchanger 18. More specifically, the outdoor unit temperature sensor 52e in this embodiment detects the temperature of the refrigerant on the outlet side of the outdoor heat exchanger 18.

[0128] The evaporator pressure sensor 52f is an evaporator pressure detection unit that detects the evaporator-side refrigerant pressure Pe, which is the pressure of the refrigerant in the indoor evaporator 19. More specifically, the evaporator pressure sensor 52f in this embodiment detects the pressure of the refrigerant on the outlet side of the indoor evaporator 19.

[0129] The evaporator temperature sensor 52g is an evaporator temperature detection unit that detects the evaporator-side refrigerant temperature Te, which is the temperature of the refrigerant in the indoor evaporator 19. More specifically, the evaporator temperature sensor 52g in this embodiment detects the heat exchange fin temperature of the indoor evaporator 19.

[0130] The intake temperature sensor 52i is an intake pressure detection unit that detects the intake refrigerant temperature Ts, which is the temperature of the refrigerant being drawn into the compressor 11. The intake pressure sensor 52h is an intake pressure detection unit that detects the intake refrigerant pressure Ps, which is the pressure of the refrigerant being drawn into the compressor 11.

[0131] The battery coolant temperature sensor 53a is a battery coolant temperature detection unit that detects the battery-side coolant temperature TWB, which is the temperature of the low-temperature heat transfer medium on the outlet side of the coolant passage 80a of the battery 80. The equipment coolant temperature sensor 53b is an equipment coolant temperature detection unit that detects the equipment-side coolant temperature TWM, which is the temperature of the low-temperature heat transfer medium on the outlet side of the coolant passage 81a of the high-voltage equipment 81.

[0132] The battery temperature sensor 54 is a battery temperature detection unit that detects the battery temperature TB, which is the temperature of the battery 80. The battery temperature sensor 54 has multiple temperature sensors and detects the temperature at multiple locations on the battery 80. Therefore, the control device 50 can detect the temperature difference and temperature distribution of each battery cell that makes up the battery 80. Furthermore, the average value of the detected values ​​from the multiple temperature sensors is used as the battery temperature TB.

[0133] The air conditioning air temperature sensor 55 is an air conditioning air temperature detection unit that detects the TAV (Total Air Temperature) of the air blown from the mixing space 46 into the vehicle cabin.

[0134] Furthermore, as shown in Figure 4, an operation panel 59 located near the instrument panel at the front of the vehicle interior is connected to the input side of the control device 50 by wire or wireless. Operation signals from various operation switches provided on the operation panel 59 are input to the control device 50.

[0135] The various control switches provided on the control panel 59 include, specifically, an auto switch, an air conditioner switch, an airflow setting switch, a temperature setting switch, and an indoor / outdoor air setting switch.

[0136] The auto switch is an automatic control setting unit that sets or cancels the automatic control operation of the vehicle air conditioning system 1. The air conditioner switch is a cooling request unit that requests the indoor evaporator 19 to cool the blown air. The airflow setting switch is an airflow setting unit that manually sets the airflow rate of the indoor blower 42. The temperature setting switch is a temperature setting unit that sets the set temperature Tset inside the vehicle. The indoor / outdoor air setting switch is an indoor / outdoor air setting unit that manually sets the operating state of the indoor / outdoor air switching device 43.

[0137] In this embodiment, the control device 50 is configured with an integrated control unit that controls various controlled devices connected to its output side. Therefore, the configuration (hardware and software) that controls the operation of each controlled device constitutes the control unit that controls the operation of each controlled device.

[0138] For example, within the control device 50, the configuration that controls the refrigerant discharge capacity of the compressor 11 constitutes the discharge capacity control unit 50a. Furthermore, the configuration that controls the operation of the refrigerant circuit switching unit constitutes the refrigerant circuit control unit 50b. Additionally, the configuration that controls the operation of the heat transfer medium circuit switching unit constitutes the heat transfer medium circuit control unit 50c.

[0139] Furthermore, the control device 50 of this embodiment can also acquire temperature information of various in-vehicle equipment and information regarding the charging and discharging status of the battery 80 from another control device or the like.

[0140] Next, the operation of the vehicle air conditioning system 1 of this embodiment in the above configuration will be described. In the vehicle air conditioning system 1 of this embodiment, various operating modes can be switched in order to control the air conditioning inside the vehicle and the temperature of the in-vehicle equipment. Switching of operating modes is performed by executing a control program that is stored in advance in the control device 50.

[0141] The control program is executed not only when the vehicle system's start switch (the so-called ignition switch) is turned on and the vehicle system is running, but also when the battery 80 is being charged from an external power source, etc.

[0142] The control program reads the detection signals from the control sensors mentioned above and the operation signals from the control panel 59. Based on the read detection and operation signals, it calculates the target discharge temperature TAO, which is the target temperature of the air blown into the vehicle cabin. Furthermore, it selects an operating mode based on the detection signals, operation signals, target discharge temperature TAO, etc., and controls the operation of various controlled devices according to the selected operating mode.

[0143] Subsequently, until the termination condition of the control program is met, the control routine described above—including reading the detection signal and operation signal, calculating the target discharge temperature (TAO), selecting the operating mode, and controlling various controlled devices—is repeated at predetermined control cycles.

[0144] The target discharge temperature TAO is calculated using the following formula F3.

[0145]

number

[0146] Tset is the set temperature inside the vehicle, as set by the temperature setting switch. Tr is the interior temperature detected by the interior temperature sensor 51a. Tam is the exterior temperature detected by the exterior temperature sensor 51b. As is the solar radiation detected by the solar radiation sensor 51c. Kset, Kr, Kam, and Ks are control gains, and C is a correction constant.

[0147] First, we will explain the operating modes for air conditioning inside the vehicle: (a) cooling mode, (b) outside air heat absorption heating mode, and (c) outside air heat absorption parallel dehumidification heating mode.

[0148] (a) Cooling mode The cooling mode is an operating mode that cools the interior of the vehicle by blowing cooled air into the cabin. The cooling mode is often selected when the auto switch and air conditioning switch are turned on, and the outside temperature Tam is relatively high, or when the target outlet temperature TAO is relatively low.

[0149] In the cooling mode heat pump cycle 10, the control device 50 closes the first on-off valve 14a, opens the second on-off valve 14b, and closes the third on-off valve 14c. The control device 50 also fully opens the heating flow control valve 16a, throttles the cooling flow control valve 16b to exert a refrigerant pressure reduction effect, fully closes the cooling flow control valve 16c, and fully closes the bypass flow control valve 16d.

[0150] Therefore, in the cooling mode heat pump cycle 10, as shown by the black arrows in Figure 5, the refrigerant discharged from the compressor 11 is switched to a refrigerant circuit that circulates in the following order: indoor condenser 12, heating flow control valve 16a (which is in a fully open state), outdoor heat exchanger 18, receiver 15, cooling flow control valve 16b, indoor evaporator 19, refrigerant suction port 721 of the ejector 70, then refrigerant outlet 723 of the ejector 70, and finally the suction port of the compressor 11. Accordingly, the usage mode of the ejector 70 in cooling mode is the passage mode.

[0151] Furthermore, the control device 50 controls the refrigerant discharge capacity of the compressor 11 so that the evaporator-side refrigerant temperature Te detected by the evaporator temperature sensor 52g approaches the target evaporator temperature TEO. The target evaporator temperature TEO is determined based on the target discharge temperature TAO by referring to a control map pre-stored in the control device 50. In the control map, it is determined that the target evaporator temperature TEO increases as the target discharge temperature TAO increases.

[0152] Furthermore, the control device 50 controls the throttle opening of the cooling flow control valve 16b so that the superheat SHE of the refrigerant at the outlet of the indoor evaporator 19 approaches a predetermined reference superheat KSH (5°C in this embodiment). The control device 50 detects the superheat SHE of the refrigerant at the outlet of the indoor evaporator 19 using the evaporator-side refrigerant pressure Pe and evaporator-side refrigerant temperature Te detected by the evaporator pressure sensor 52f.

[0153] In the cooling mode, the low-temperature side heat transfer medium circuit 30 operates the low-temperature side heat transfer medium pump 31 to achieve a predetermined standard pumping capacity.

[0154] Furthermore, the control device 50 determines the opening pattern of the first heat transfer medium flow rate control valve 36a to the third heat transfer medium flow rate control valve 36c by referring to a control map pre-stored in the control device 50, based on the battery-side coolant temperature TWB detected by the battery coolant temperature sensor 53a and the equipment-side coolant temperature TWM detected by the equipment coolant temperature sensor 53b.

[0155] The control map determines the opening pattern so that the battery-side coolant temperature TWB approaches a predetermined reference battery-side coolant temperature KTWB, and the equipment-side coolant temperature TWM approaches a predetermined reference equipment-side coolant temperature KTWM. The reference battery-side coolant temperature KTWB is set to a value that allows the battery 80 to be cooled to an appropriate temperature. The reference equipment-side coolant temperature KTWM is set to a value that allows the high-voltage equipment 81 to be cooled to an appropriate temperature.

[0156] In the indoor air conditioning unit 40 in cooling mode, the control device 50 controls the airflow capacity of the indoor blower 42 based on the target discharge temperature TAO, by referring to a control map that has been pre-stored in the control device 50.

[0157] The control map determines that the fan capacity is maximized when the target outlet temperature TAO is in the extremely low temperature range (i.e., maximum cooling) or the extremely high temperature range (i.e., maximum heating). Furthermore, it determines that the fan capacity decreases as the target outlet temperature TAO moves from the extremely low or extremely high temperature range to the intermediate temperature range. Finally, it determines that the fan capacity is minimized when the target outlet temperature TAO is in the intermediate temperature range.

[0158] Furthermore, the control device 50 controls the operation of the electric actuator for the air mix door 44 so that the supplied air temperature TAV1 detected by the air conditioning air temperature sensor 55 approaches the target discharge temperature TAO.

[0159] Furthermore, the control device 50 controls the operation of the indoor / outdoor air switching device 43 by referring to a control map pre-stored in the control device 50, based on the operation signal and the target discharge temperature TAO. The control device 50 also controls the operation of the electric actuator for the discharge mode door by referring to a control map pre-stored in the control device 50, based on the target discharge temperature TAO. In addition, the control device 50 appropriately controls the operation of other controlled devices.

[0160] Therefore, in the cooling mode heat pump cycle 10, the state of the refrigerant changes as shown in the Mollier diagram in Figure 6. Here, in the following Mollier diagrams described in this embodiment, the state of the refrigerant at the locations indicated by the symbols (alphabetical letters) in the overall configuration diagram of Figure 1 is represented using the same symbols (alphabetical letters).

[0161] In cooling mode, the refrigerant discharged from the compressor 11 (point a6 in Figure 6) flows into the indoor condenser 12. The refrigerant flowing into the indoor condenser 12 condenses and releases heat into the blown air according to the opening of the air mix door 44 (from point a6 to point b6 in Figure 6). As a result, the blown air is heated in the indoor condenser 12.

[0162] In Figure 6, points a6 and b6 are shown as different points for clarity of the illustration. However, if the air mix door 44 is blocking the air passage on the indoor condenser 12 side, the refrigerant will not release heat into the supplied air at the indoor condenser 12. Therefore, if the air mix door 44 is blocking the air passage on the indoor condenser 12 side, points b6 and a6 in Figure 6 coincide. This is also true in other operating modes.

[0163] The refrigerant flowing out of the indoor condenser 12 flows into the outdoor heat exchanger 18 via the fully open heating flow control valve 16a. The refrigerant flowing into the outdoor heat exchanger 18 condenses by releasing heat into the outside air. Furthermore, the refrigerant flowing out of the outdoor heat exchanger 18 flows into the receiver 15 where it undergoes gas-liquid separation (from point b6 to point g6 in Figure 6).

[0164] The liquid-phase refrigerant flowing out from the receiver 15 flows into the cooling flow control valve 16b and is depressurized (from point g6 to point i6 in Figure 6). The refrigerant, depressurized in the cooling flow control valve 16b, flows into the indoor evaporator 19. The refrigerant flowing into the indoor evaporator 19 absorbs heat from the blown air and evaporates (from point i6 to point j6 in Figure 6). As a result, the blown air is cooled in the indoor evaporator 19.

[0165] The refrigerant that flows out from the indoor evaporator 19 is drawn into the compressor 11 via the ejector 70, which functions as a refrigerant passage, and is compressed again (from point j6 to point a6 in Figure 6).

[0166] In the cooling mode, the low-temperature heat transfer medium circuit 30 flows into the heat transfer medium passage of the chiller 20, as shown by the dashed arrow in Figure 5, through pressurized delivery from the low-temperature heat transfer medium pump 31. In cooling mode, no refrigerant is introduced into the refrigerant passage of the chiller 20, so the low-temperature heat transfer medium that flows into the chiller 20 flows out of the chiller 20 without any temperature change.

[0167] The flow of the low-temperature heat transfer fluid that flows out of the chiller 20 is branched at the first heat transfer fluid three-way joint 33a. One of the low-temperature heat transfer fluids branched off at the first heat transfer fluid three-way joint 33a flows into the cooling water passage 80a of the battery 80, depending on the opening of the first heat transfer fluid flow control valve 36a. The low-temperature heat transfer fluid that flows into the cooling water passage 80a of the battery 80 exchanges heat with the battery 80 and absorbs heat. This cools the battery 80.

[0168] Furthermore, the low-temperature side heat transfer medium branched off at the first three-way heat transfer medium joint 33a flows into the second three-way heat transfer medium joint 33b. The flow of the low-temperature side heat transfer medium that flows into the second three-way heat transfer medium joint 33b flows into the cooling water passage 81a and the low-temperature side radiator 32 of the high-voltage equipment 81, according to the opening degree of the second heat transfer medium flow control valve 36b and the opening degree of the third heat transfer medium flow control valve 36c.

[0169] The low-temperature heat transfer medium that flows into the cooling water passage 81a of the high-voltage equipment 81 absorbs heat by exchanging heat with the high-voltage equipment 81. This cools the high-voltage equipment 81. The low-temperature heat transfer medium that flows into the low-temperature radiator 32 dissipates heat by exchanging heat with the outside air. This cools the low-temperature heat transfer medium. The flow of the low-temperature heat transfer medium that flows out from the cooling water passage 81a of the high-voltage equipment 81 and the flow of the low-temperature heat transfer medium that flows out from the low-temperature radiator 32 merge at the third heat transfer medium three-way joint 33c.

[0170] Furthermore, the flow of the low-temperature heat transfer medium that flows out from the third heat transfer medium three-way joint 33c and the flow of the low-temperature heat transfer medium that flows out from the cooling water passage 80a of the battery 80 merge at the fourth heat transfer medium three-way joint 33d. The low-temperature heat transfer medium that flows out from the fourth heat transfer medium three-way joint 33d is drawn into the low-temperature heat transfer medium pump 31 and pumped back to the heat transfer medium passage side of the chiller 20.

[0171] Here, the first heat transfer medium flow control valves 36a to the third heat transfer medium flow control valves 36c have a fully closed function. Therefore, depending on the determined opening pattern, they may be in a fully closed state. For example, if the first heat transfer medium flow control valve 36a is in a fully closed state, the low-temperature heat transfer medium will not flow into the cooling water passage 80a of the battery 80. In other words, the low-temperature heat transfer medium may not flow, as shown by the dashed arrow in Figure 5. This is also true in other operating modes.

[0172] In the indoor air conditioning unit 40 in cooling mode, air introduced via the indoor / outdoor air switching device 43 is drawn into the indoor fan 42 and blown out. The blown air from the indoor fan 42 flows into the indoor evaporator 19 and is cooled. The blown air cooled in the indoor evaporator 19 flows into the air passage on the indoor condenser 12 side and the cold air bypass passage 45, depending on the opening degree of the air mix door 44.

[0173] The air flowing into the air passage on the side of the indoor condenser 12 is heated as it passes through the indoor condenser 12 and then flows into the mixing space 46. The air flowing into the cold air bypass passage 45 flows into the mixing space 46 without being heated. The air that is mixed and temperature-adjusted in the mixing space 46 is then blown out through the openings to the appropriate locations in the vehicle interior. This provides air conditioning to the vehicle interior.

[0174] (b) Outdoor air heating mode The outside air intake heating mode is an operating mode that heats the vehicle interior by blowing heated air into the cabin. This mode is often selected when the auto switch and air conditioning switch are on, and the outside temperature Tam is relatively low, or when the target outlet temperature TAO is relatively high.

[0175] In the heat pump cycle 10 of the outside air heat intake heating mode, the control device 50 opens the first on-off valve 14a, closes the second on-off valve 14b, and opens the third on-off valve 14c. In addition, the control device 50 sets the heating flow control valve 16a to a throttled state, the cooling flow control valve 16b to a fully closed state, the cooling flow control valve 16c to a fully closed state, and the bypass side flow control valve 16d to a fully closed state.

[0176] Therefore, in the heat pump cycle 10 of the outside air heat absorption heating mode, as shown by the black arrows in Figure 7, the refrigerant discharged from the compressor 11 is switched to a refrigerant circuit that circulates in the following order: indoor condenser 12, receiver 15, heating flow control valve 16a, outdoor heat exchanger 18, refrigerant suction port 721 of the ejector 70, then refrigerant outlet 723 of the ejector 70, and finally the suction port of the compressor 11. Accordingly, the usage mode of the ejector 70 in the outside air heat absorption heating mode is the passage mode.

[0177] Furthermore, the control device 50 controls the refrigerant discharge capacity of the compressor 11 so that the discharge refrigerant pressure Pd detected by the discharge pressure sensor 52a approaches the target high-pressure PDO. The target high-pressure PDO is determined based on the target blow-off temperature TAO by referring to a control map pre-stored in the control device 50. In the control map, it is determined that the target high-pressure PDO increases as the target blow-off temperature TAO increases.

[0178] Furthermore, the control device 50 controls the throttle opening of the heating flow control valve 16a so that the superheat level SHS of the suction refrigerant approaches the reference superheat level KSH. The control device 50 detects the superheat level SHS of the suction refrigerant using the suction refrigerant pressure Ps detected by the suction pressure sensor 52h and the suction refrigerant temperature Ts detected by the suction temperature sensor 52i.

[0179] In the low-temperature side heat transfer medium circuit 30 of the outside air heat intake heating mode, the control device 50 controls the operation of various controlled devices, similar to the cooling mode.

[0180] In the indoor air conditioning unit 40 operating in outside air heating mode, the control device 50 controls the operation of various controlled devices, similar to the cooling mode. Furthermore, the control device 50 appropriately controls the operation of other controlled devices.

[0181] Therefore, in the heat pump cycle 10 of the outside air intake heating mode, the state of the refrigerant changes as shown in the Mollier diagram in Figure 8. In Figure 8, symbols (alphabetical letters) are used, similar to the Mollier diagram in Figure 6. Furthermore, the subscripts (numbers) have been changed to match the figure number compared to Figure 6. This is also the case in the Mollier diagrams described below.

[0182] In the outside air heat absorption heating mode, the refrigerant discharged from the compressor 11 (point a8 in Figure 8) flows into the indoor condenser 12. The refrigerant flowing into the indoor condenser 12 condenses by releasing heat into the blown air according to the opening of the air mix door 44. As a result, the blown air is heated in the indoor condenser 12. Furthermore, the refrigerant flowing out of the indoor condenser 12 flows into the receiver 15 where it undergoes gas-liquid separation (from point a8 to point g8 in Figure 8).

[0183] The liquid-phase refrigerant flowing out of the receiver 15 flows into the heating flow control valve 16a and is depressurized (from point g8 to point d8 in Figure 8). The refrigerant, depressurized in the heating flow control valve 16a, flows into the outdoor heat exchanger 18. The refrigerant flowing into the outdoor heat exchanger 18 absorbs heat from the outside air and evaporates (from point d8 to point e8 in Figure 8).

[0184] The refrigerant that flows out from the outdoor heat exchanger 18 is drawn into the compressor 11 via the ejector 70, which functions as a refrigerant passage, and is compressed again (from point e8 to point a8 in Figure 8).

[0185] In the low-temperature side heat transfer medium circuit 30 of the outside air heat intake heating mode, the low-temperature side heat transfer medium circulates, as shown by the dashed arrow in Figure 7, similar to the cooling mode. This cools the battery 80 and the high-voltage equipment 81.

[0186] In the indoor air conditioning unit 40 operating in outside air heating mode, the air blown from the indoor fan 42 passes through the indoor evaporator 19, just as in cooling mode. In outside air heating mode, no refrigerant is introduced into the indoor evaporator 19, so the air that enters the indoor evaporator 19 flows out without any temperature change.

[0187] The air that has passed through the indoor evaporator 19 flows into the air passage on the indoor condenser 12 side and the cold air bypass passage 45, depending on the opening of the air mix door 44. Then, similar to the cooling mode, the air that has been mixed and temperature-adjusted in the mixing space 46 is blown out through the opening to the appropriate location in the vehicle interior. This achieves heating of the vehicle interior.

[0188] (c) Outdoor air heat absorption parallel dehumidification heating mode The outside air heat absorption parallel dehumidification heating mode is an operating mode that dehumidifies and heats the vehicle interior by reheating cooled and dehumidified blown air and blowing it into the vehicle interior. The outside air heat absorption parallel dehumidification heating mode is often selected when the auto switch and air conditioner switch are on and the outside temperature Tam is in the intermediate temperature range, or when the target blown temperature TAO is in the intermediate temperature range.

[0189] In the heat pump cycle 10 of the outside air heat absorption parallel dehumidification heating mode, the control device 50 opens the first on-off valve 14a, closes the second on-off valve 14b, and opens the third on-off valve 14c. The control device 50 also throttles the heating flow control valve 16a, throttles the cooling flow control valve 16b, fully closes the cooling flow control valve 16c, and fully closes the bypass side flow control valve 16d.

[0190] Therefore, in the heat pump cycle 10 of the outside air heat absorption parallel dehumidification heating mode, as shown by the black arrows in Figure 9, the refrigerant discharged from the compressor 11 is switched to a refrigerant circuit that circulates in the following order: indoor condenser 12, receiver 15, heating flow control valve 16a, outdoor heat exchanger 18, refrigerant suction port 721 of the ejector 70, then refrigerant outlet 723 of the ejector 70, and finally the suction port of the compressor 11. At the same time, the refrigerant discharged from the compressor 11 is switched to a refrigerant circuit that circulates in the following order: indoor condenser 12, receiver 15, cooling flow control valve 16b, indoor evaporator 19, refrigerant suction port 721 of the ejector 70, then refrigerant outlet 723 of the ejector 70, and finally the suction port of the compressor 11.

[0191] In other words, in the heat pump cycle 10 of the outside air heat absorption parallel dehumidification heating mode, the refrigerant circuit is switched to one in which the outdoor heat exchanger 18 and the indoor evaporator 19 are connected in parallel to the flow of refrigerant discharged from the receiver 15. Furthermore, the usage mode of the ejector 70 in the outside air heat absorption parallel dehumidification heating mode is the passage mode.

[0192] Furthermore, the control device 50 controls the refrigerant discharge capacity of the compressor 11, similar to the cooling mode. The control device 50 also controls the throttle opening of the cooling flow control valve 16b so that the supplied air can be dehumidified within a range that suppresses frost formation on the indoor evaporator 19. Furthermore, the control device 50 controls the throttle opening of the heating flow control valve 16a, similar to the outside air heat intake heating mode.

[0193] In the low-temperature side heat transfer medium circuit 30 of the outside air heat absorption parallel dehumidification heating mode, the control device 50 controls the operation of various controlled devices, similar to the cooling mode.

[0194] In the indoor air conditioning unit 40 operating in the outside air heat absorption parallel dehumidification heating mode, the control device 50 controls the operation of various controlled devices, similar to the cooling mode. Furthermore, the control device 50 appropriately controls the operation of other controlled devices.

[0195] Therefore, in the heat pump cycle 10 of the outside air heat absorption parallel dehumidification heating mode, the state of the refrigerant changes as shown in the Mollier diagram in Figure 10.

[0196] Specifically, the refrigerant discharged from the compressor 11 (point a10 in Figure 10) flows into the indoor condenser 12. The refrigerant flowing into the indoor condenser 12 condenses by releasing heat into the blown air according to the opening of the air mix door 44. As a result, the blown air is heated in the indoor condenser 12. Furthermore, the refrigerant flowing out of the indoor condenser 12 flows into the receiver 15 where it undergoes gas-liquid separation (from point a10 to point g10 in Figure 10).

[0197] The liquid phase refrigerant flowing out from the receiver 15 flows into the seventh three-way joint 13g and is branched. The refrigerant flowing out from one outlet of the seventh three-way joint 13g flows into the heating flow control valve 16a and is depressurized (from point g10 to point d10 in Figure 10). The refrigerant depressurized in the heating flow control valve 16a flows into the outdoor heat exchanger 18. The refrigerant flowing into the outdoor heat exchanger 18 absorbs heat from the outside air and evaporates (from point d10 to point f10 in Figure 10).

[0198] The refrigerant flowing out from the other outlet of the seventh three-way joint 13g flows into the cooling flow control valve 16b and is depressurized (from point g10 to point i10 in Figure 10). The refrigerant depressurized in the cooling flow control valve 16b flows into the indoor evaporator 19. The refrigerant flowing into the indoor evaporator 19 absorbs heat from the blown air and evaporates (from point i10 to point f10 in Figure 10). As a result, the blown air is cooled and dehumidified in the indoor evaporator 19.

[0199] The refrigerant flow from the outdoor heat exchanger 18 and the refrigerant flow from the indoor evaporator 19 flow into the ninth three-way joint 13i and merge. The refrigerant flowing out from the ninth three-way joint 13i is drawn into the compressor 11 via the ejector 70, which functions as a refrigerant passage, and is compressed again (from point f10 to point a10 in Figure 10).

[0200] In the low-temperature side heat transfer medium circuit 30 of the outside air heat absorption parallel dehumidification heating mode, the low-temperature side heat transfer medium circulates, similar to the cooling mode, as shown by the dashed arrow in Figure 9. This cools the battery 80 and the high-voltage equipment 81.

[0201] In the indoor air conditioning unit 40 operating in the outside air heat absorption parallel dehumidification heating mode, the air blown from the indoor fan 42 is cooled and dehumidified in the indoor evaporator 19, similar to the cooling mode.

[0202] The dehumidified air supplied by the indoor evaporator 19 flows into the air passage on the indoor condenser 12 side and the cold air bypass passage 45, depending on the opening of the air mix door 44. Then, similar to the cooling mode, the air supplied is mixed in the mixing space 46 and temperature-adjusted, and blown out through the opening to the appropriate location in the vehicle interior. This achieves dehumidified heating in the vehicle interior.

[0203] In the above-mentioned (a) cooling mode, (b) outside air heat absorption heating mode, and (c) outside air heat absorption parallel dehumidification heating mode, the cooling capacity of the heat pump cycle 10 is not used to cool the in-vehicle equipment. In contrast, the vehicle air conditioning system 1 can execute a cooling operation mode that uses the cooling capacity of the heat pump cycle 10 to cool the in-vehicle equipment.

[0204] As described above, in this embodiment, the upper limit temperature of the battery 80 is lower than the standard heat resistance temperature of the high-voltage equipment 81. Therefore, the control program of this embodiment determines whether or not it is necessary to cool the in-vehicle equipment using the cooling capacity of the heat pump cycle 10, based on the temperature of the battery 80.

[0205] Specifically, when the battery temperature TB detected by the battery temperature sensor 54 exceeds a predetermined reference battery temperature KTB, it is determined that it is necessary to cool the battery 80 using the cooling capacity of the heat pump cycle 10. Alternatively, when the battery-side cooling water temperature TWB exceeds the reference battery-side cooling water temperature KTWB, it is determined that it is necessary to cool the battery 80 using the cooling capacity of the heat pump cycle 10.

[0206] The following describes the cooling operation modes: (d) Battery-only cooling mode, (e) Cooling with battery cooling mode, (f) Outdoor air heat absorption and waste heat heating mode, and (g) Outdoor air heat absorption and waste heat parallel dehumidification and heating mode.

[0207] (d) Battery-only cooling mode The battery-only cooling mode is an operating mode that is executed when it is determined that the battery 80 needs to be cooled using the cooling capacity of the heat pump cycle 10, such as when the vehicle is being charged and the air conditioning in the vehicle cabin is not being used.

[0208] In the battery-only cooling mode of the heat pump cycle 10, the control device 50 closes the first on-off valve 14a, opens the second on-off valve 14b, and closes the third on-off valve 14c. The control device 50 also fully opens the heating flow control valve 16a, fully closes the cooling flow control valve 16b, restricts the cooling flow control valve 16c, and fully closes the bypass flow control valve 16d.

[0209] Therefore, in the battery-only cooling mode of the heat pump cycle 10, as shown by the white arrows in Figure 11, the refrigerant discharged from the compressor 11 is switched to a refrigerant circuit that circulates in the following order: indoor condenser 12, heating flow control valve 16a (which is fully open), outdoor heat exchanger 18, receiver 15, cooling flow control valve 16c, chiller 20, refrigerant suction port 721 of the ejector 70, then refrigerant outlet 723 of the ejector 70, and finally the suction port of the compressor 11. Accordingly, the usage mode of the ejector 70 in the battery-only cooling mode is the passage mode.

[0210] Furthermore, the control device 50 controls the refrigerant discharge capacity of the compressor 11 so that the battery temperature TB approaches the target battery temperature KTB2, or so that the battery-side cooling water temperature TWB approaches the target battery-side cooling water temperature KTWB2.

[0211] The target battery temperature KTB2 is determined based on the battery-side coolant temperature TWB by referring to a control map pre-stored in the control device 50. The target battery-side coolant temperature KTWB2 is determined based on the battery-side coolant temperature TWB by referring to a control map pre-stored in the control device 50. Both the target battery temperature KTB2 and the target battery-side coolant temperature KTWB2 are set to ensure that the battery 80 is properly cooled.

[0212] Furthermore, the control device 50 controls the throttle opening of the cooling flow control valve 16c so that the superheat level SHS of the intake refrigerant approaches the reference superheat level KSH.

[0213] In the low-temperature heat transfer medium circuit 30 of the battery-only cooling mode, the control device 50 controls the operation of various controlled devices in the same way as in the cooling mode.

[0214] In the indoor air conditioning unit 40 operating in battery-only cooling mode, the control device 50 stops the indoor fan 42. Furthermore, the control device 50 appropriately controls the operation of other controlled devices.

[0215] Therefore, in the heat pump cycle 10 of the battery-only cooling mode, the state of the refrigerant changes as shown in the Mollier diagram in Figure 12.

[0216] In other words, the refrigerant discharged from the compressor 11 (point a12 in Figure 12) flows into the indoor condenser 12. In battery-only cooling mode, the indoor blower 42 is stopped. Therefore, the refrigerant in the indoor condenser 12 does not dissipate heat into the blown air.

[0217] The refrigerant flowing out of the indoor condenser 12 flows into the outdoor heat exchanger 18 via the fully open heating flow control valve 16a. The refrigerant flowing into the outdoor heat exchanger 18 condenses by releasing heat into the outside air. Furthermore, the refrigerant flowing out of the outdoor heat exchanger 18 flows into the receiver 15 where it undergoes gas-liquid separation (from point a12 to point g12 in Figure 12).

[0218] The liquid-phase refrigerant flowing out of the receiver 15 flows into the cooling flow control valve 16c and is depressurized (from point g12 to point k12 in Figure 12). The refrigerant depressurized in the cooling flow control valve 16c flows into the chiller 20. The refrigerant flowing into the chiller 20 absorbs heat from the low-temperature side heat transfer medium and evaporates (from point k12 to point j12 in Figure 12). As a result, the low-temperature side heat transfer medium is cooled in the chiller 20.

[0219] The liquid-phase refrigerant that flows out of the chiller 20 is drawn into the compressor 11 via the ejector 70, which functions as a refrigerant passage, and is compressed again (from point j12 to point a12 in Figure 12).

[0220] In the low-temperature heat transfer medium circuit 30 of the battery-only cooling mode, as shown by the dashed arrow in Figure 11, the low-temperature heat transfer medium pumped from the low-temperature heat transfer medium pump 31 flows into the heat transfer medium passage of the chiller 20. The low-temperature heat transfer medium that flows into the chiller 20 is cooled by the refrigerant absorbing its heat.

[0221] The low-temperature heat transfer medium cooled by the chiller 20 flows into the cooling water passage 80a of the battery 80, similar to the cooling mode. This cools the battery 80. Furthermore, the low-temperature heat transfer medium cooled by the chiller 20 flows into the cooling water passage 81a of the high-voltage equipment 81, similar to the cooling mode. This cools the high-voltage equipment 81.

[0222] Therefore, in battery-only cooling mode, the battery 80 and high-voltage equipment 81 can be cooled using the cooling capacity of the heat pump cycle 10 without the need for air conditioning in the vehicle cabin.

[0223] Of course, the interior fan 42 may also be operated when the battery is in standalone cooling mode. In this case, the control device 50 controls the operation of the air mix door 44 so as to close the air passage on the interior condenser 12 side, thereby enabling operation in a fan mode that blows untemperature-controlled air into the vehicle interior.

[0224] (e) Cooling Battery Cooling Mode The cooling battery cooling mode is an operating mode that is executed when it is determined that the battery 80 needs to be cooled using the cooling capacity of the heat pump cycle 10 while the cooling mode is running.

[0225] In the heat pump cycle 10 of the cooling battery cooling mode, the control device 50 restricts the cooling flow control valve 16c for the cooling mode. More specifically, the control device 50 controls the restriction opening of the cooling flow control valve 16c to a predetermined restriction opening for the cooling battery cooling mode.

[0226] Therefore, in the heat pump cycle 10 of the cooling battery cooling mode, the system switches to a refrigerant circuit in which the refrigerant circulates in the order shown by the white arrows in Figure 5. In other words, in the heat pump cycle 10 of the cooling battery cooling mode, the system switches to a refrigerant circuit in which the indoor evaporator 19 and chiller 20 are connected in parallel to the flow of refrigerant discharged from the receiver 15. Furthermore, the ejector 70 is used in passage mode in the cooling battery cooling mode.

[0227] In Figure 5, for clarity, the refrigerant flow path added to the cooling mode is shown with a thick dashed line. This is also the case in Figures 7 and 9. Other operations are the same as in the cooling mode.

[0228] Therefore, in the heat pump cycle 10 of the cooling battery cooling mode, the state of the refrigerant changes as shown in the Mollier diagram in Figure 13.

[0229] In other words, similar to the cooling mode, the refrigerant flowing into the indoor condenser 12 condenses by releasing heat into the blown air (from point a13 to point b13 in Figure 13). As a result, the blown air is heated in the indoor condenser 12. Furthermore, the refrigerant flowing into the outdoor heat exchanger 18 condenses by releasing heat into the outside air (from point b13 to point g13 in Figure 13).

[0230] Also, similar to the cooling mode, the refrigerant (point d13 in Figure 13), which has been depressurized by the cooling flow control valve 16b, evaporates in the indoor evaporator 19 by absorbing heat from the blown air. As a result, the blown air is cooled in the indoor evaporator 19. The refrigerant that flows out of the indoor evaporator 19 flows into one of the inlets of the ninth three-way joint 13i (from point d13 to point j13 in Figure 13).

[0231] Furthermore, similar to the battery-only cooling mode, the refrigerant (point k13 in Figure 13), which has been depressurized by the cooling flow control valve 16c, absorbs heat from the low-temperature heat transfer medium in the chiller 20 and evaporates. As a result, the low-temperature heat transfer medium is cooled in the chiller 20. The refrigerant that flows out of the chiller 20 flows into the other inlet of the ninth three-way joint 13i (from point k13 to point j13 in Figure 13).

[0232] The flow of refrigerant discharged from the indoor evaporator 19 and the flow of refrigerant discharged from the chiller 20 merge at the ninth three-way joint 13i. The refrigerant discharged from the ninth three-way joint 13i is drawn into the compressor 11 via the sixth three-way joint 13f and the ejector 70, which functions as a refrigerant passage, and is compressed again (from point j13 to point a13 in Figure 13).

[0233] In the low-temperature side heat transfer medium circuit 30 of the cooling battery mode, the low-temperature side heat transfer medium circulates, similar to the battery-only cooling mode. This cools the battery 80 and the high-voltage equipment 81.

[0234] In the cooling battery cooling mode, the interior air conditioning unit 40 blows temperature-controlled air through openings to appropriate locations within the vehicle interior, similar to the cooling mode. This achieves cooling within the vehicle interior.

[0235] Therefore, in the air conditioning battery cooling mode, air conditioning can be achieved inside the vehicle, and the battery 80 and high-voltage equipment 81 can be cooled using the cooling capacity of the heat pump cycle 10.

[0236] (f) Outdoor air heat intake waste heat heating mode The outside air heat absorption waste heat heating mode is an operating mode that is executed when it is determined that cooling of the battery 80 using the cooling capacity of the heat pump cycle 10 is necessary while the outside air heat absorption heating mode is running.

[0237] In the heat pump cycle 10 of the outside air heat intake and waste heat heating mode, the control device 50 throttles the cooling flow control valve 16c for the outside air heat intake and heating mode. More specifically, the control device 50 controls the throttling opening of the cooling flow control valve 16c to a predetermined throttling opening for the outside air heat intake and waste heat heating mode.

[0238] Therefore, in the heat pump cycle 10 of the outside air heat absorption and waste heat heating mode, the refrigerant circuit is switched to one in which the refrigerant circulates in the order shown by the white arrows in Figure 7. In other words, in the heat pump cycle 10 of the outside air heat absorption and waste heat heating mode, the refrigerant circuit is switched to one in which the outdoor heat exchanger 18 and chiller 20 are connected in parallel to the flow of refrigerant flowing out from the receiver 15. Furthermore, the ejector 70 is used in the passage mode in the outside air heat absorption and waste heat heating mode. Other operations are the same as in the outside air heat absorption and heating mode.

[0239] Therefore, in the heat pump cycle 10 of the outside air heat absorption and waste heat heating mode, the state of the refrigerant changes as shown in the Mollier diagram of Figure 14. That is, similar to the outside air heat absorption heating mode, the refrigerant that flows into the indoor condenser 12 releases heat into the blown air and condenses (from point a14 to point g14 in Figure 14). As a result, the blown air is heated in the indoor condenser 12.

[0240] Furthermore, similar to the outside air heat absorption heating mode, the refrigerant (point d14 in Figure 14), which has been depressurized by the heating flow control valve 16a, absorbs heat from the outside air and evaporates in the outdoor heat exchanger 18. The refrigerant that flows out from the outdoor heat exchanger 18 flows into one of the inlets of the sixth three-way joint 13f (from point d14 to point f14 in Figure 14).

[0241] Furthermore, similar to the battery-only cooling mode, the refrigerant (point k14 in Figure 14), which has been depressurized by the cooling flow control valve 16c, absorbs heat from the low-temperature heat transfer medium in the chiller 20 and evaporates. As a result, the low-temperature heat transfer medium is cooled in the chiller 20. The refrigerant that flows out of the chiller 20 flows through the ninth three-way joint 13i to the sixth three-way joint 13f, which is the other inlet (from point k14 to point f14 in Figure 14).

[0242] The flow of refrigerant discharged from the outdoor heat exchanger 18 and the flow of refrigerant discharged from the chiller 20 merge at the sixth three-way joint 13f. The refrigerant discharged from the sixth three-way joint 13f is drawn into the compressor 11 via the ejector 70, which functions as a refrigerant passage, and is compressed again (from point f14 to point a14 in Figure 14).

[0243] In the low-temperature side heat transfer medium circuit 30 of the outside air heat intake waste heat heating mode, the low-temperature side heat transfer medium circulates, similar to the battery-only cooling mode. This cools the battery 80 and the high-voltage equipment 81.

[0244] In the indoor air conditioning unit 40 operating in the outside air heat intake and waste heat heating mode, temperature-controlled air is blown out through openings to appropriate locations within the vehicle interior, similar to the outside air heat intake and heating mode. This achieves heating within the vehicle interior.

[0245] Therefore, in the outside air heat absorption waste heat heating mode, heating of the vehicle interior can be achieved, and the battery 80 and high-voltage electrical equipment 81 can be cooled using the cooling capacity of the heat pump cycle 10. Furthermore, in the outside air heat absorption waste heat heating mode, the waste heat from the battery 80 and high-voltage electrical equipment 81 can be absorbed by the refrigerant via the low-temperature heat transfer medium in the chiller 20 and used as a heat source to heat the blown air in the indoor condenser 12.

[0246] (g) Outdoor air heat absorption, waste heat parallel dehumidification heating mode The outside air heat absorption parallel waste heat dehumidification heating mode is an operating mode that is executed when it is determined that cooling of the battery 80 using the cooling capacity of the heat pump cycle 10 is necessary while the outside air heat absorption parallel dehumidification heating mode is running.

[0247] In the heat pump cycle 10 operating in the outside air heat absorption - waste heat parallel dehumidification heating mode, the control device 50 places the cooling flow rate adjustment valve 16c in a throttled state for the outside air heat absorption parallel dehumidification heating mode. More specifically, the control device 50 controls the throttle opening degree of the cooling flow rate adjustment valve 16c so that the throttle opening degree matches a predetermined opening degree for the outside air heat absorption - waste heat parallel dehumidification heating mode.

[0248] Therefore, in the heat pump cycle 10 operating in the outside air heat absorption - waste heat parallel dehumidification heating mode, the refrigerant circuit is switched to one in which refrigerant circulates in the order shown by the hollow arrows in Fig. 9. That is, in the heat pump cycle 10 operating in the outside air heat absorption - waste heat parallel dehumidification heating mode, the refrigerant circuit is switched to one where the outdoor heat exchanger 18, the indoor evaporator 19, and the chiller 20 are connected in parallel to the flow of refrigerant flowing out from the receiver 15. Furthermore, the ejector 70 is operated in the passage mode in the outside air heat absorption - waste heat parallel dehumidification heating mode. Other operations are the same as those in the outside air heat absorption parallel dehumidification heating mode.

[0249] Accordingly, in the heat pump cycle 10 operating in the outside air heat absorption - waste heat parallel dehumidification heating mode, the state of the refrigerant changes as shown in the Mollier diagram of Fig. 15.

[0250] That is, similar to the outside air heat absorption parallel dehumidification heating mode, the refrigerant flowing into the indoor condenser 12 dissipates heat to the blown air and condenses (from point a15 to point g15 in Fig. 15). As a result, the blown air is heated in the indoor condenser 12.

[0251] Furthermore, similar to the outside air heat absorption parallel dehumidification heating mode, the refrigerant depressurized by the heating flow rate adjustment valve 16a (point d15 in Fig. 15) absorbs heat from outside air and evaporates in the outdoor heat exchanger 18. The refrigerant flowing out from the outdoor heat exchanger 18 flows into one inlet port of the sixth three-way joint 13f (from point d15 to point f15 in Fig. 15).

[0252] Similarly to the outdoor air heat absorption parallel dehumidification heating mode, the refrigerant depressurized by the cooling flow rate adjustment valve 16b (point i15 in Fig. 15) absorbs heat from the blown air and evaporates in the indoor evaporator 19. Accordingly, the blown air is cooled and dehumidified in the indoor evaporator 19. The refrigerant flowing out from the indoor evaporator 19 flows into the other inflow port of the sixth three-way joint 13f via the ninth three-way joint 13i (from point i15 to point f15 in Fig. 15).

[0253] Similarly to the independent battery cooling mode, the refrigerant depressurized by the cooling flow rate adjustment valve 16c (point k15 in Fig. 15) absorbs heat from the low-temperature side heat medium and evaporates in the chiller 20. Accordingly, the low-temperature side heat medium is cooled in the chiller 20. The refrigerant flowing out from the chiller 20 flows into the other inflow port of the sixth three-way joint 13f via the ninth three-way joint 13i (from point k15 to point f15 in Fig. 15).

[0254] The flow of refrigerant flowing out from the indoor evaporator 19 and the flow of refrigerant flowing out from the chiller 20 merge at the ninth three-way joint 13i. The flow of refrigerant flowing out from the ninth three-way joint 13i and the flow of refrigerant flowing out from the outdoor heat exchanger 18 merge at the sixth three-way joint 13f. The refrigerant flowing out from the sixth three-way joint 13f is sucked into the compressor 11 via the ejector 70 functioning as a refrigerant passage and compressed again (from point f15 to point a15 in Fig. 15).

[0255] In the low-temperature side heat medium circuit 30 in the outdoor air heat absorption waste heat parallel dehumidification heating mode, the low-temperature side heat medium circulates similarly to the independent battery cooling mode. Accordingly, the battery 80 and the high-voltage electrical equipment 81 are cooled.

[0256] In the indoor air conditioning unit 40 in the outdoor air heat absorption waste heat parallel dehumidification heating mode, similarly to the outdoor air heat absorption parallel dehumidification heating mode, the temperature-adjusted blown air is blown out to an appropriate position in the vehicle cabin through the opening hole. Accordingly, dehumidification heating of the vehicle cabin is achieved.

[0257] Therefore, in the outside air heat absorption waste heat parallel dehumidification heating mode, dehumidification heating can be achieved inside the vehicle, and the battery 80 and high-voltage equipment 81 can be cooled using the cooling capacity of the heat pump cycle 10. Furthermore, in the outside air heat absorption waste heat parallel dehumidification heating mode, the waste heat from the battery 80 and high-voltage equipment 81 can be absorbed by the refrigerant via the low-temperature heat transfer medium in the chiller 20 and used as a heat source to heat the blown air in the indoor condenser 12.

[0258] Furthermore, the vehicle air conditioning system 1 of this embodiment can perform an operating mode in which refrigerant is not introduced into the outdoor heat exchanger 18. The following describes the operating modes in which refrigerant is not introduced into the outdoor heat exchanger 18: (h) evaporator-only dehumidification heating mode, (i) waste heat heating mode, and (j) waste heat parallel dehumidification heating mode.

[0259] (h) Evaporator-only dehumidifying heating mode In the heat pump cycle 10 of the evaporator-only dehumidifying and heating mode, the control device 50 opens the first on-off valve 14a, closes the second on-off valve 14b, and closes the third on-off valve 14c. The control device 50 also sets the heating flow control valve 16a to a fully closed state, the cooling flow control valve 16b to a throttled state, the cooling flow control valve 16c to a fully closed state, and the bypass side flow control valve 16d to a fully closed state.

[0260] Therefore, in the heat pump cycle 10 of the evaporator-only dehumidifying heating mode, as shown by the black arrows in Figure 16, the refrigerant discharged from the compressor 11 is switched to a refrigerant circuit that circulates in the following order: indoor condenser 12, receiver 15, cooling flow control valve 16b, indoor evaporator 19, refrigerant suction port 721 of the ejector 70, then refrigerant outlet 723 of the ejector 70, and finally the suction port of the compressor 11. Accordingly, the usage mode of the ejector 70 in the evaporator-only dehumidifying heating mode is the passage mode. Other operations are the same as in the cooling mode.

[0261] Therefore, in the heat pump cycle 10 of the evaporator-only dehumidifying heating mode, the state of the refrigerant changes as shown in the Mollier diagram of Figure 17. That is, similar to the cooling mode, the refrigerant flowing into the indoor condenser 12 condenses by releasing heat into the blown air. As a result, the blown air is heated in the indoor condenser 12. Furthermore, the refrigerant flowing out of the indoor condenser 12 flows into the receiver 15 and undergoes gas-liquid separation (from point a17 to point g17 in Figure 17).

[0262] Also, similar to the cooling mode, the refrigerant, which has been depressurized by the cooling flow control valve 16b, evaporates in the indoor evaporator 19 by absorbing heat from the blown air (from point i17 to point j17 in Figure 17). As a result, the blown air is cooled and dehumidified in the indoor evaporator 19. The refrigerant that has flowed out of the indoor evaporator 19 is drawn into the compressor 11 via the ejector 70, which functions as a refrigerant passage, and is compressed again (from point j17 to point a17 in Figure 17).

[0263] In the low-temperature side heat transfer medium circuit 30 of the evaporator-only dehumidifying heating mode, the low-temperature side heat transfer medium circulates, similar to the cooling mode. This cools the battery 80 and the high-voltage electrical equipment 81.

[0264] In the indoor air conditioning unit 40 operating in evaporator-only dehumidification and heating mode, temperature-controlled air is blown through openings to appropriate locations within the vehicle interior, similar to the outside air heat absorption parallel dehumidification and heating mode. This achieves dehumidification and heating within the vehicle interior.

[0265] (i) Waste heat heating mode In the waste heat heating mode of the heat pump cycle 10, the control device 50 opens the first on-off valve 14a, closes the second on-off valve 14b, and closes the third on-off valve 14c. The control device 50 also sets the heating flow control valve 16a to a fully closed state, the cooling flow control valve 16b to a fully closed state, the cooling flow control valve 16c to a throttled state, and the bypass side flow control valve 16d to a fully closed state.

[0266] Therefore, in the waste heat heating mode of the heat pump cycle 10, as shown by the black arrows in Figure 18, the refrigerant discharged from the compressor 11 is switched to a refrigerant circuit that circulates in the following order: indoor condenser 12, receiver 15, cooling flow control valve 16c, chiller 20, refrigerant suction port 721 of the ejector 70, then refrigerant outlet 723 of the ejector 70, and finally the suction port of the compressor 11. Accordingly, the mode of use of the ejector 70 in waste heat heating mode is the passage mode.

[0267] Furthermore, the control device 50 controls the refrigerant discharge capacity of the compressor 11, similar to the outside air heat absorption heating mode. Here, if cooling of the battery 80 is prioritized over heating the vehicle interior, the refrigerant discharge capacity of the compressor 11 may be controlled, similar to the battery-only cooling mode. Also, the control device 50 controls the throttle opening of the cooling flow control valve 16c, similar to the battery-only cooling mode. Other operations are the same as in the cooled outside air heat absorption heating mode.

[0268] Therefore, in the waste heat heating mode of the heat pump cycle 10, the state of the refrigerant changes as shown in the Mollier diagram in Figure 19. That is, similar to the evaporator-only dehumidification heating mode, the refrigerant flowing into the indoor condenser 12 condenses by releasing heat into the blown air. As a result, the blown air is heated in the indoor condenser 12. Furthermore, the refrigerant flowing out of the indoor condenser 12 flows into the receiver 15 and undergoes gas-liquid separation (from point a19 to point g19 in Figure 19).

[0269] Also, similar to the battery-only cooling mode, the refrigerant (point k19 in Figure 19), which has been depressurized by the cooling flow control valve 16c, absorbs heat from the low-temperature heat transfer medium in the chiller 20 and evaporates (from point k19 to point j19 in Figure 19). As a result, the low-temperature heat transfer medium is cooled in the chiller 20. The refrigerant that has flowed out of the chiller 20 is drawn into the compressor 11 via the ejector 70, which functions as a refrigerant passage, and is compressed again (from point j19 to point a19 in Figure 19).

[0270] In the low-temperature heat transfer medium circuit 30 of the waste heat heating mode, the low-temperature heat transfer medium circulates, similar to the battery-only cooling mode. This cools the battery 80 and the high-voltage equipment 81.

[0271] In the indoor air conditioning unit 40 operating in the waste heat heating mode, similarly to the outside air heat absorption heating mode, temperature-adjusted blown air is blown out to an appropriate location in the vehicle compartment through the opening hole. Thereby, heating of the vehicle compartment is achieved. Furthermore, in the waste heat heating mode, the waste heat from the battery 80 and high-voltage system equipment 81 is absorbed into the refrigerant via the low-temperature side heat medium by the chiller 20, and can be used as a heat source for heating blown air by the indoor condenser 12.

[0272] (j) Waste heat parallel dehumidification heating mode In the heat pump cycle 10 operating in the waste heat parallel dehumidification heating mode, the control device 50 opens the first on-off valve 14a, closes the second on-off valve 14b, and closes the third on-off valve 14c. Further, the control device 50 fully closes the heating flow rate adjustment valve 16a, throttles the cooling flow rate adjustment valve 16b, throttles the cooling flow rate adjustment valve 16c, and fully closes the bypass-side flow rate adjustment valve 16d.

[0273] Therefore, in the heat pump cycle 10 operating in the waste heat parallel dehumidification heating mode, as indicated by the black arrows in FIG. 20, the refrigerant discharged from the compressor 11 is switched to a refrigerant circuit that circulates in the order of the indoor condenser 12, the receiver 15, the cooling flow rate adjustment valve 16b, the indoor evaporator 19, the refrigerant suction port 721 of the ejector 70, the refrigerant outlet 723 of the ejector 70, and the suction port of the compressor 11. At the same time, the refrigerant discharged from the compressor 11 is switched to a refrigerant circuit that circulates in the order of the indoor condenser 12, the receiver 15, the cooling flow rate adjustment valve 16c, the chiller 20, the refrigerant suction port 721 of the ejector 70, the refrigerant outlet 723 of the ejector 70, and the suction port of the compressor 11.

[0274] That is, in the heat pump cycle 10 operating in the waste heat parallel dehumidification heating mode, the refrigerant circuit is switched to one in which the indoor evaporator 19 and the chiller 20 are connected in parallel with respect to the flow of refrigerant flowing out from the receiver 15. Furthermore, the usage mode of the ejector 70 in the waste heat parallel dehumidification heating mode is the passage mode.

[0275] Furthermore, the control device 50 controls the throttle opening of the cooling flow control valve 16c, similar to the battery-only cooling mode. Other operations are the same as in the cooling mode.

[0276] Therefore, in the heat pump cycle 10 of the waste heat parallel dehumidification heating mode, the state of the refrigerant changes as shown in the Mollier diagram in Figure 21. That is, similar to the evaporator-only dehumidification heating mode, the refrigerant flowing into the indoor condenser 12 condenses by releasing heat into the blown air. As a result, the blown air is heated in the indoor condenser 12. Furthermore, the refrigerant flowing out of the indoor condenser 12 flows into the receiver 15 and undergoes gas-liquid separation (from point a21 to point g21 in Figure 21).

[0277] Furthermore, similar to the cooling battery cooling mode, the refrigerant (point i21 in Figure 21), which has been depressurized by the cooling flow control valve 16b, evaporates in the indoor evaporator 19 by absorbing heat from the blown air. As a result, the blown air is cooled and dehumidified in the indoor evaporator 19. The refrigerant that flows out of the indoor evaporator 19 flows into one of the inlets of the ninth three-way joint 13i (from point i21 to point j21 in Figure 21).

[0278] Furthermore, similar to the air conditioning battery cooling mode, the refrigerant (point k21 in Figure 21), which has been depressurized by the cooling flow control valve 16c, absorbs heat from the low-temperature heat transfer medium in the chiller 20 and evaporates. As a result, the low-temperature heat transfer medium is cooled in the chiller 20. The refrigerant that flows out of the chiller 20 flows into the other inlet of the ninth three-way joint 13i (from point k21 to point j21 in Figure 21).

[0279] The flow of refrigerant discharged from the indoor evaporator 19 and the flow of refrigerant discharged from the chiller 20 merge at the ninth three-way joint 13i. The refrigerant discharged from the ninth three-way joint 13i is drawn into the compressor 11 via the sixth three-way joint 13f and the ejector 70, which functions as a refrigerant passage, and is compressed again (from point j21 to point a21 in Figure 21).

[0280] In the low-temperature side heat transfer medium circuit 30 of the waste heat parallel dehumidification heating mode, the low-temperature side heat transfer medium circulates, similar to the battery-only cooling mode. This cools the battery 80 and the high-voltage equipment 81.

[0281] In the waste heat parallel dehumidification heating mode of the indoor air conditioning unit 40, temperature-controlled air is blown out through openings to appropriate locations within the vehicle interior, similar to the outside air heat absorption parallel dehumidification heating mode. This achieves dehumidification and heating within the vehicle interior.

[0282] Furthermore, in the waste heat parallel dehumidification heating mode, the chiller 20 can use the waste heat from the battery 80 and the high-voltage electrical equipment 81 to be absorbed by the refrigerant via the low-temperature heat transfer medium, and this can be used as a heat source to heat the blown air in the indoor condenser 12.

[0283] In the above-mentioned modes (b) outdoor air heat absorption heating mode, (c) outdoor air heat absorption parallel dehumidification heating mode, (f) outdoor air heat absorption waste heat heating mode, and (g) outdoor air heat absorption waste heat parallel dehumidification heating mode, the refrigerant evaporation temperature in the outdoor heat exchanger 18 is below the ambient temperature. Therefore, if these operating modes are executed at low ambient temperatures, frost may form on the outdoor heat exchanger 18.

[0284] Therefore, when it is determined that the conditions for frost formation, which are presumed to be present on the outdoor heat exchanger 18, have been met, the system may operate in defrost mode to defrost the outdoor heat exchanger 18. For example, the conditions for frost formation can be determined to be met when the time during which the outdoor unit refrigerant temperature T1 is below the standard frost formation temperature (e.g., -5°C) is equal to or greater than the standard frost formation time (e.g., 5 minutes).

[0285] For defrosting mode, for example, (a) the compressor 11 can be operated by switching to the same refrigerant circuit as in cooling mode. This allows the high-temperature refrigerant discharged from the compressor 11 to flow into the outdoor heat exchanger 18, thereby defrosting the outdoor heat exchanger 18. Furthermore, in defrosting mode, the refrigerant discharge capacity of the compressor 11 may be controlled to exhibit a predetermined refrigerant discharge capacity for defrosting.

[0286] Furthermore, if frost conditions are met while (c) the outside air heat absorption parallel dehumidification heating mode is in operation, the system can switch to the same refrigerant circuit as in (a) the cooling mode to defrost the outdoor heat exchanger 18. This eliminates the need to change the control modes of the cooling flow control valve 16b and the cooling flow control valve 16c, allowing for prompt defrosting of the outdoor heat exchanger 18.

[0287] Similarly, if frost conditions are met while (f) the outside air heat absorption waste heat heating mode is running, the outdoor heat exchanger 18 can be quickly defrosted by switching to the same refrigerant circuit as in (d) the battery-only cooling mode. Similarly, if frost conditions are met while (g) the outside air heat absorption waste heat parallel dehumidification heating mode is running, the outdoor heat exchanger 18 can be quickly defrosted by switching to the same refrigerant circuit as in (e) the cooling battery cooling mode.

[0288] Furthermore, in the vehicle air conditioning system 1 of this embodiment, a hot gas operation mode can be executed in which refrigerant is introduced into the nozzle section 71 when the outside temperature Tam is at an extremely low outside temperature.

[0289] When the outside temperature Tam is extremely low, it is difficult for the outdoor heat exchanger 18 to absorb the heat from the outside air into the refrigerant, and difficult for the chiller 20 to absorb the heat from the low-temperature heat transfer medium into the refrigerant. Therefore, in hot gas operation mode, the heat generated by the compression work of the compressor 11 is mainly used to heat the blown air, etc.

[0290] Furthermore, in hot gas operation mode, refrigerant is introduced into the nozzle section 71, so the ejector 70 is used in either (β) nozzle mode or (γ) suction mode. Therefore, before explaining the hot gas operation mode, we will describe the functions of the ejector 70 in (β) nozzle mode and (γ) suction mode.

[0291] (β) Nozzle Mode In nozzle mode, the control device 50 closes at least one of the first to third on-off valves 14a to 14c in order to block the refrigerant flow path communicating with the refrigerant suction port 721. Furthermore, the control device 50 fully closes at least one of the heating flow control valve 16a, the cooling flow control valve 16b, and the cooling flow control valve 16c.

[0292] Furthermore, the control device 50 controls the throttle opening of the bypass-side flow control valve 16d so that the injected refrigerant sprayed from the nozzle section 71 becomes over-expanded. Specifically, the control device 50 controls the throttle opening of the bypass-side flow control valve 16d by referring to a control map pre-stored in the control device 50 based on the suction refrigerant pressure Ps and the discharge refrigerant pressure Pd.

[0293] Here, we will explain how to determine the throttle opening of the bypass-side flow rate adjustment unit 16d in the control map. First, we define Uin as the velocity of the refrigerant flowing into the nozzle inlet 711 of the nozzle unit 71 in the Z-axis direction, and Uz as the velocity of the refrigerant in the Z-axis direction at a point at a distance z from the nozzle inlet 711 in the Z-axis direction.

[0294] Uz can be expressed by the mathematical formula F4.

[0295]

number

[0296] ΔHz is the adiabatic enthalpy drop of the refrigerant during the expansion process at a distance Z in the Z-axis direction from the nozzle inlet 711. Δhf is the energy loss due to wall friction and other factors within the nozzle section 71.

[0297] Therefore, the Mach number Mz of the refrigerant at a distance Z in the Z-axis direction from the nozzle inlet 711 can be expressed by formula F5.

[0298]

number

[0299] Sa is the speed of sound of the refrigerant. The Mach number Mz shown in equation F5 represents the Mach number obtained by the adiabatic enthalpy drop at the nozzle section 71.

[0300] Next, we define the passage cross-sectional area at a distance Z in the Z-axis direction from the nozzle inlet 711 as Az, and the passage cross-sectional area at the throat portion 713 as Ath. In the refrigerant passage of the nozzle portion 71, the Reynolds number of the refrigerant is relatively high, so the energy loss Δhf is negligible.

[0301] The relationship between the cross-sectional area ratio of Ath to Az (Az / Ath) and the refrigerant pressure Pz at a distance Z in the Z-axis direction from the nozzle inlet 711 can be expressed by the following equation F6. Furthermore, the relationship between the cross-sectional area ratio (Az / Ath) and the Mach number Mz can be expressed by the following equation F7.

[0302]

number

[0303]

number

[0304] Pin is the refrigerant pressure at the nozzle inlet 711. γtp is the specific heat of the refrigerant at the nozzle inlet 711.

[0305] Then, applying the passage cross-sectional area Anout at the nozzle 715 to equations F6 and F7, the Mach number Mnout of the refrigerant injected from the nozzle 715 can be expressed by the following equations F8 and F9.

[0306]

number

[0307]

number

[0308] The Mach number Mnout shown in formula F9 represents the Mach number obtained by the area ratio of the passages in the nozzle section 71.

[0309] Therefore, when the Mach number Mnout is less than or equal to the Mach number Mz, the refrigerant can be accelerated to a speed greater than the speed of sound (Mach number 1 or greater) within the refrigerant passage of the nozzle section 71 and injected from the nozzle 715. As a result, a shock wave is generated when the refrigerant injected from the nozzle section 71 into the mixing and pressurizing section 722 becomes subsonic outside the nozzle section 71. In this state, where the refrigerant outside the refrigerant passage of the nozzle section 71 injected from the nozzle 715 generates a shock wave, the injected refrigerant is in an under-expanded state.

[0310] On the other hand, if the Mach number Mnout is greater than the Mach number Mz, the refrigerant in the refrigerant passage of the nozzle section 71 cannot be accelerated to a speed greater than Mz obtained by the adiabatic enthalpy drop, and subsonic refrigerant is injected from the nozzle 715. As a result, a shock wave is generated when the supersonic refrigerant becomes subsonic in the refrigerant passage of the nozzle section 71. Thus, the state in which the refrigerant in the refrigerant passage of the nozzle section 71 generates a shock wave indicates that the injected refrigerant is in an over-expanded state.

[0311] Therefore, by controlling the throttle opening of the bypass-side flow control valve 16d and adjusting the refrigerant pressure Pin at the nozzle inlet 711, the injected refrigerant can be made to be in an under-expanded or over-expanded state.

[0312] As described above, in nozzle mode, the throttle opening of the bypass-side flow control valve 16d is controlled so that the injected refrigerant becomes over-expanded. Therefore, in nozzle mode, the pressure of the refrigerant increases in the refrigerant passage of the nozzle section 71 due to the action of shock waves.

[0313] Here, we define the Mach number of the refrigerant immediately before the shock wave as Mz1, and the pressure of the refrigerant immediately before the shock wave as Pz1. Furthermore, we define the pressure of the refrigerant at the refrigerant outlet 723 of the ejector 70 as Pout. In this case, the first boost ratio (Pout / Pz1), which is the ratio of Pout to Pz1, can be expressed by the following formula F10.

[0314]

number

[0315] As shown in equation F10, the first boost ratio (Pout / Pz1) is maximized when the shock wave angle β = 90°, i.e., when a vertical shock wave is formed, provided that the Mach number Mz1 is constant.

[0316] In contrast, our own research has shown that if the Mach number Mz1 is determined to satisfy the following equation F11, the shock wave angle β can be brought close to 90°.

[0317]

number

[0318] Therefore, in the control map of this embodiment, the throttle opening of the bypass-side flow control valve 16d is determined to satisfy the above formula F11. In other words, in the nozzle mode control map, the throttle opening of the bypass-side flow control valve 16d is determined to generate a vertical shock wave in the refrigerant passage of the nozzle section 71.

[0319] As described above, in nozzle mode, the ejector 70 can rapidly increase the pressure of the refrigerant flowing out of the refrigerant outlet 723 of the ejector 70 due to the pressure-boosting effect of the shock wave generated in the refrigerant passage of the nozzle section 71. In other words, the ejector 70 in nozzle mode exhibits the function of rapidly increasing the suction refrigerant pressure Ps of the suction refrigerant drawn into the compressor 11.

[0320] (γ) Suction mode In suction mode, the control device 50 opens at least one of the first to third on-off valves 14a to 14c in order to draw refrigerant from the refrigerant suction port 721 of the ejector 70. Furthermore, the control device 50 sets at least one of the heating flow control valve 16a, the cooling flow control valve 16b, and the cooling flow control valve 16c to either a fully open or throttled state.

[0321] Furthermore, the control device 50 controls the throttle opening of the bypass-side flow control valve 16d so that the injected refrigerant is in an under-expansion state. Specifically, similar to the nozzle mode, the control device 50 controls the throttle opening of the bypass-side flow control valve 16d by referring to a control map pre-stored in the control device 50 based on the intake refrigerant pressure Ps and discharge refrigerant pressure Pd.

[0322] In suction mode, the injected refrigerant enters an under-expanded state, generating an expansion wave at the injection port 715 of the nozzle section 71. The pressure drop caused by the expansion wave then draws in the gas-liquid two-phase refrigerant from the refrigerant suction port 721. The ejector 70 can generate a refrigerant suction effect sufficient to bring the refrigerant flow path communicating with the refrigerant suction port 721 close to a vacuum state due to the pressure drop caused by the expansion wave.

[0323] Furthermore, the refrigerant is accelerated as it passes through the expansion wave. Here, the relationship between the Mach number Mnout of the refrigerant injected from nozzle 715 and the Mach number Mnoutexp of the refrigerant immediately after passing through the first expansion wave (i.e., the first expansion wave) can be expressed by the following equations F12 to F14.

[0324]

number

[0325]

number

[0326]

number

[0327] θ is the deflection angle of the refrigerant injected from the nozzle 715. More specifically, the deflection angle θ is the value obtained by subtracting the spread angle θ2 of the flared portion 714 from the spread angle θ1 of the trailing expansion wave, as shown in Figure 22. The white circles in Figure 22 indicate droplets contained in the suctioned refrigerant.

[0328] According to the inventors' tests and studies, it has been confirmed that the refrigerant passing through the expansion wave undergoes isentropically reduced pressure expansion. Therefore, the second pressure reduction ratio (Pnoutexp / Pnout) of the refrigerant pressure Pnoutexp immediately after passing through the expansion wave relative to the refrigerant injection pressure Pnout at the injection port 715 can be expressed by the following formula F15.

[0329]

number

[0330] γtp1 is the specific heat of the mixed refrigerant in the upstream part of the shock wave, which is a mixture of the injected refrigerant sprayed from the nozzle section 71 and the suctioned refrigerant drawn in from the refrigerant suction port 721.

[0331] Furthermore, the expansion wave generated at the injection port 715 is reflected by the turbulent boundary layer in the mixing section 722a of the mixing and pressurizing section 722, as schematically shown in Figure 22, generating a shock wave.

[0332] Since the refrigerant upstream of the shock wave is accelerated to Mach number Mnoutexp, the second pressure boost ratio (Pout / Pnoutexp), which is the ratio of the refrigerant pressure Pout at the refrigerant outlet 723 to the pressure Pnoutexp due to the pressure boosting effect of the shock wave, can be expressed by the following formula F16.

[0333]

number

[0334] Furthermore, the average refrigerant pressure inside the ejector 70, when the injected refrigerant is in an under-expansion state, changes in the Z-axis direction as shown in Figure 23. As shown in Figure 23, when the injected refrigerant is in an under-expansion state, the second pressure boost ratio (Pout / Pnoutexp) due to the shock wave generated in the mixing section 722a becomes a high value of about 2 to 6, and the pressure boosting capacity of the ejector 70 approaches the maximum pressure boosting state.

[0335] The vertical axis on the left side of Figure 23 shows the pressure reduction ratio (Pz / Pin) of the refrigerant pressure Pz at a distance Z relative to the refrigerant pressure Pin at the nozzle inlet 711. The vertical axis on the right side of Figure 23 shows the pressure increase ratio (Pz / Pnoutexp) of the refrigerant pressure Pz at a distance Z relative to the refrigerant pressure Pnoutexp immediately after passing through the expansion wave.

[0336] Next, considering the energy conservation of the refrigerant in the mixing and pressurizing unit 722 during suction mode, we can derive the following equation F17.

[0337]

number

[0338] Unoutexp is the velocity of the refrigerant in the Z-axis direction after passing through the expansion wave. hnoutexp is the enthalpy of the refrigerant after passing through the expansion wave. Usin is the velocity of the gas-liquid two-phase refrigerant drawn in from the refrigerant suction port 721 in the Z-axis direction. hsin is the enthalpy of the gas-liquid two-phase refrigerant drawn in from the refrigerant suction port 721. Uout is the velocity of the refrigerant flowing out from the refrigerant outlet 723 in the Z-axis direction. hout is the enthalpy of the refrigerant flowing out from the refrigerant outlet 723.

[0339] Furthermore, by rearranging equation F17 using the flow rate Gd of the refrigerant injected from the nozzle 71 and the flow rate Gs of the refrigerant drawn in from the refrigerant suction port 721, the following equation F18 can be derived.

[0340]

number

[0341] Δhnoutexp is the enthalpy reduction of the refrigerant that is isentropically reduced by the bypass flow control valve 16d and the nozzle section 71, as shown in the Mollier diagram in Figure 24. Δh2 is the enthalpy increase due to the compression work of the shock wave (from point P24 to point s24 in Figure 24).

[0342] In the ejector 70 in suction mode, the mixed refrigerant, which is a mixture of a superheated gaseous refrigerant injected from the nozzle 71 and a gaseous two-phase refrigerant drawn in from the refrigerant suction port 721, can be brought close to equilibrium in the mixing section 722a. Therefore, the specific enthalpy of the mixed refrigerant in equilibrium can be adjusted by adjusting the flow rate ratio between the flow rate Gd of the injected refrigerant injected from the nozzle 71 and the flow rate Gs of the suctioned refrigerant drawn in from the refrigerant suction port 721.

[0343] Then, by increasing the pressure of the mixed refrigerant through the compression work of the shock wave, the refrigerant flowing out from the refrigerant outlet 723 (point s24 in Figure 24) can be reliably converted into a superheated gaseous refrigerant, as shown in the Mollier diagram of Figure 24.

[0344] Next, we will describe the pressure change of the refrigerant downstream of the first shock wave (i.e., the first shock wave) generated within the mixing and pressurizing section 722.

[0345] In the suction mode mixing section 722a, the injected refrigerant flows into the center and the suctioned refrigerant flows into the outer periphery. Therefore, in addition to the turbulent boundary layer, a velocity boundary layer is formed at the inlet side of the mixing section 722a due to the velocity difference between the injected and suctioned refrigerants. Consequently, the morphology of the first shock wave generated by reflection from the turbulent boundary layer tends to be unstable.

[0346] Therefore, as in the nozzle mode, simply adjusting the refrigerant flow velocity to adjust the shock wave angle β makes it difficult to reliably bring the pressure boosting capability of the ejector 70 close to the maximum pressure boosting state. According to studies by the present inventors, it has been confirmed that in the suction mode, morphological changes occur in the shock wave as schematically shown in Figs. 25 to 28.

[0347] Fig. 25 shows the morphological change of the shock wave in the mixing pressure boosting portion 722 under the first operating condition where 1 < Mnoutexp ≤ 1.2. Under the first operating condition, similar to the over-expansion state described in the nozzle mode, the shock wave angle β approaches 90°, and the shape of the shock wave approaches a normal shock wave.

[0348] Fig. 26 shows the morphological change of the shock wave in the mixing pressure boosting portion 722 under the second operating condition where 1.2 < Mnoutexp ≤ 1.3. Under the second operating condition, along with the development of the turbulent boundary layer, the shape of the shock wave changes to an oblique shock wave.

[0349] Fig. 27 shows the morphological change of the shock wave in the mixing pressure boosting portion 722 under the third operating condition where 1.3 < Mnoutexp ≤ 1.5. Under the third operating condition, along with the further development of the turbulent boundary layer, a branched shock wave called λ shock wave is formed.

[0350] Fig. 28 shows the morphological change of the shock wave in the mixing pressure boosting portion 722 under the fourth operating condition where 1.5 < Mnoutexp. Under the fourth operating condition, a pseudo shock wave in which a plurality of shock waves and expansion waves repeatedly occur is generated. The pseudo shock wave is generated when the expansion wave is reflected by the developed turbulent boundary layer.

[0351] Under the fourth operating condition, as shown in Fig. 29, when the refrigerant passes through the repeatedly generated shock waves, the pressure is increased and the entropy is increased. In Fig. 29, the static pressure on the central axis side in the mixing pressure boosting portion 722 is indicated by a thick solid line, and the static pressure on the wall surface side in the mixing pressure boosting portion 722 is indicated by a thick broken line. The pseudo shock wave disappears when the velocity of the refrigerant decreases to subsonic speed.

[0352] Furthermore, in the region where a pseudo-shock wave is generated, a supersonic refrigerant is present, so increasing the cross-sectional area of ​​the passage in the mixing and pressurizing section 722 will decrease the static pressure on the wall side of the mixing and pressurizing section 722.

[0353] From the above findings, it was found that in suction mode, rather than adjusting the unstable shock wave angle β, it is more effective to continuously increase the refrigerant pressure with a pseudo-shock wave, as in the fourth operating condition, and to bring the mixed refrigerant closer to equilibrium within the mixing section 722a where the refrigerant passage cross-sectional area is constant, in order to improve the pressure boosting capability of the ejector 70.

[0354] Furthermore, as shown in Figure 29, it has been confirmed that when the pseudo-shock wave disappears, the static pressure on the central axis side within the mixing and pressurizing section 722 and the static pressure on the wall side of the mixing section 722a become equal. Therefore, the inventors adjusted the relationship between the Mach number M0 of the refrigerant at the inlet of the mixing section 722a and the disappearance distance Lx from the actual inlet of the mixing and pressurizing section 722 to the final end position of the pseudo-shock wave (i.e., the position where it disappeared).

[0355] As a result, as shown in Figure 30, a tendency was observed for the extinction distance ratio (Lx / Lv) to increase with increasing Mach number Mnoutexp. Also, as shown in Figure 30, a tendency was observed for the extinction distance ratio (Lx / Lv) to increase with increasing refrigerant dryness Xmixin at the inlet of the mixing and pressurizing unit 722.

[0356] Furthermore, considering the Mach number Mnoutexp in the actual ejector 70, it was confirmed that if the mixing interval distance L is set to about 6 times the relaxation distance Lv, the pseudo-shock wave can be extinguished within the mixing interval 722a even if the dryness Xmixin changes over a wide range. In Figure 30, the flow rate ratio of the injected refrigerant flow rate Gd to the suctioned refrigerant flow rate Gs is adjusted so that the refrigerant flowing out from the refrigerant outlet 723 becomes a gaseous refrigerant with a superheated degree.

[0357] In this embodiment, the mixing section distance L is set to satisfy the above-described formulas F1 and F2, so that pseudo-shock waves can be eliminated within the mixing section 722a under a wide range of operating conditions.

[0358] As described above, in the ejector 70 in suction mode, by appropriately adjusting the throttle opening of the flow control valve, which is in a throttled state, the refrigerant flowing out from the refrigerant outlet 723 of the ejector 70 can be made into a gaseous refrigerant in equilibrium state. Furthermore, by eliminating the pseudo-shock wave in the mixing section 722a, a pressurization function is achieved that sufficiently increases the pressurization of the refrigerant flowing out from the refrigerant outlet 723 of the ejector 70.

[0359] In other words, the ejector 70 in suction mode performs the function of raising the suction refrigerant pressure Ps to a level sufficiently higher than the refrigerant pressure at the refrigerant suction port 721 by the action of shock waves.

[0360] Next, we will describe the following hot gas operating modes for introducing refrigerant into the nozzle section 71: (k) hot gas start mode, (l) hot gas heating mode, (m) hot gas waste heat heating mode, (n) hot gas outside air intake heating mode, (o) hot gas parallel dehumidification heating mode, and (p) hot gas defrost heating mode.

[0361] (k) Hot gas start mode The hot gas start mode is a warm-up operating mode for heating the refrigerant in the heat pump cycle 10 before executing the hot gas heating mode or the like, in order to improve the heating capacity (i.e., heating capacity) of the air blown by the vehicle air conditioning system 1.

[0362] The hot gas startup mode is executed when the vehicle air conditioning system 1 is started, the outside temperature Tam is extremely low, and the intake refrigerant temperature Ts is lower than a predetermined standard hot gas temperature KHGTs. In other words, it is executed when the compressor 11 is started, the hot gas operation mode is selected, and the intake refrigerant temperature Ts is lower than the standard hot gas temperature KHGTs.

[0363] In the hot gas-started heat pump cycle 10, the control device 50 closes the first on-off valve 14a, the second on-off valve 14b, and the third on-off valve 14c. The control device 50 also fully closes the heating flow control valve 16a, the cooling flow control valve 16b, and the cooling flow control valve 16c, and throttles the bypass flow control valve 16d.

[0364] Therefore, in the hot gas start-up mode of the heat pump cycle 10, as shown by the black arrows in Figure 31, the refrigerant discharged from the compressor 11 flows through the bypass-side flow control valve 16d located in the bypass passage 21c, then through the nozzle section 71 of the ejector 70, and further, the refrigerant flowing out from the refrigerant outlet 723 of the ejector 70 is drawn into the compressor 11, switching to a refrigerant circuit. Thus, the mode of use of the ejector 70 in the hot gas start-up mode is nozzle mode.

[0365] Furthermore, the control device 50 controls the refrigerant discharge capacity of the compressor 11 at a low rotational speed within a range where liquid compression problems do not occur. This is because when the ambient temperature Tam is extremely low, the suction refrigerant drawn into the compressor 11 may be in a gas-liquid two-phase state.

[0366] Furthermore, the control device 50 controls the throttle opening of the bypass-side flow control valve 16d so that the injected refrigerant sprayed from the nozzle section 71 becomes over-expanded. Specifically, the control device 50 controls the throttle opening of the bypass-side flow control valve 16d by referring to a control map pre-stored in the control device 50 based on the suction refrigerant pressure Ps and the discharge refrigerant pressure Pd.

[0367] In the low-temperature heat transfer fluid circuit 30 of the hot gas start mode, the control device 50 stops the low-temperature heat transfer fluid pump 31.

[0368] In the indoor air conditioning unit 40 in hot gas start mode, the control device 50 stops the indoor blower 42.

[0369] Therefore, in the hot gas-started heat pump cycle 10, the refrigerant discharged from the compressor 11 is depressurized by the bypass-side flow control valve 16d and flows into the nozzle section 71 of the ejector 70. Within the refrigerant passage of the nozzle section 71, the pressure of the refrigerant increases due to the action of shock waves.

[0370] The refrigerant, whose pressure has increased at the nozzle section 71 of the ejector 70, flows out from the refrigerant outlet 723 via the mixing and pressure boosting section 722. The refrigerant that flows out from the refrigerant outlet 723 is drawn in by the compressor 11 and compressed again.

[0371] In hot gas startup mode, the system operates as described above, and by continuously utilizing the pressurizing effect of the nozzle section 71, the intake refrigerant pressure Ps and intake refrigerant temperature Ts can be rapidly increased.

[0372] As a result, in hot gas startup mode, the intake refrigerant can be converted into a superheated gaseous refrigerant in a relatively short time, as shown by the arrow from point s321 to point s322 in the Mollier diagram of Figure 32. Here, the dashed line in Figure 32 shows the change in the state of the refrigerant, which represents (l) the change in the state of the refrigerant during hot gas heating mode.

[0373] Furthermore, the hot gas startup mode of this embodiment is continued until the intake refrigerant temperature Ts becomes equal to or greater than the reference hot gas temperature KHGTs.

[0374] (l) Hot gas heating mode The hot gas heating mode is selected when the ambient temperature Tam is extremely low and the intake refrigerant pressure Ps is equal to or greater than the reference hot gas temperature KHGTs. Furthermore, it is executed when both the battery-side coolant temperature TWB and the equipment-side coolant temperature TWM are equal to or less than the first reference heat absorption temperature KTWE1.

[0375] The first reference endothermic temperature KTWE1 is set to a low temperature such that the low-pressure refrigerant cannot absorb heat from the low-temperature side heat transfer medium. In other words, the first reference endothermic temperature KTWE1 is set to a value lower than the lowest saturation temperature (in this embodiment, -40°C) among the saturation temperatures that the refrigerant can take after its pressure has been reduced by the suction action of the ejector 70.

[0376] In the hot gas heating mode heat pump cycle 10, the control device 50 opens the first on-off valve 14a, closes the second on-off valve 14b, and opens the third on-off valve 14c. The control device 50 also closes the heating flow control valve 16a, closes the cooling flow control valve 16b, throttles the cooling flow control valve 16c, and throttles the bypass flow control valve 16d.

[0377] Therefore, in the hot gas heating mode heat pump cycle 10, as shown by the black arrows in Figure 33, the refrigerant discharged from the compressor 11 is switched to a refrigerant circuit in which it flows in the following order: indoor condenser 12, receiver 15, cooling flow control valve 16c, chiller 20, and refrigerant suction port 721 of the ejector 70. At the same time, the refrigerant discharged from the compressor 11 is switched to a refrigerant circuit in which it flows in the following order: bypass-side flow control valve 16d located in the bypass passage 21c, and nozzle portion 71 of the ejector 70, and the refrigerant that flows out from the refrigerant outlet 723 of the ejector 70 is drawn into the compressor 11. Thus, the mode of use of the ejector 70 in the hot gas heating mode is suction mode.

[0378] Furthermore, the control device 50 controls the refrigerant discharge capacity of the compressor 11 so that the discharge refrigerant pressure Pd approaches the target high pressure PDO within a range where the generator-side refrigerant temperature Te of the indoor evaporator 19, which is the suction-side heat exchange section, is higher than the reference lower limit temperature KTem (in this embodiment, -40°C). The reference lower limit temperature KTem is determined based on the temperature at which the sealing performance of the sealing material used in pipe connections and the like can be guaranteed.

[0379] Furthermore, the control device 50 controls the throttle opening of the cooling flow control valve 16c so that the superheat SHS of the suction refrigerant flowing out from the refrigerant outlet 723 of the ejector 70 and drawn into the compressor 11 approaches the reference superheat KSH.

[0380] Furthermore, the control device 50 controls the throttle opening of the bypass-side flow control valve 16d so that the refrigerant in the nozzle section 71 is in an under-expansion state. Specifically, the control device 50 controls the throttle opening of the bypass-side flow control valve 16d by referring to a control map pre-stored in the control device 50 based on the suction refrigerant pressure Ps and the discharge refrigerant pressure Pd.

[0381] In the hot gas heating mode, the low-temperature heat transfer medium circuit 30 is stopped by the control device 50. In the overall configuration diagram of Figure 32, the low-temperature heat transfer medium circuit 30 is indicated by a dashed arrow, which represents the flow of the low-temperature heat transfer medium during the hot gas waste heat heating mode, which will be described later.

[0382] In the indoor air conditioning unit 40 operating in hot gas heating mode, the control device 50 controls the operation of the indoor / outdoor air switching device 43 so that indoor air is introduced as the blown air. Furthermore, the control device 50 appropriately controls the operation of other controlled devices.

[0383] Therefore, in the hot gas heating mode heat pump cycle 10, the state of the refrigerant changes as shown in the Mollier diagram in Figure 34. That is, the flow of refrigerant discharged from the compressor 11 (point a34 in Figure 34) is branched at the first three-way joint 13a. One of the refrigerants branched at the first three-way joint 13a flows into the indoor condenser 12.

[0384] The refrigerant flowing into the indoor condenser 12 condenses by releasing heat into the blown air according to the opening of the air mix door 44. As a result, the blown air is heated in the indoor condenser 12. In hot gas heating mode, the opening of the air mix door 44 is often controlled so that almost the entire volume of blown air from the indoor fan 42 passes through the indoor condenser 12.

[0385] The refrigerant flowing out of the indoor condenser 12 flows into the receiver 15 where it is separated into gas and liquid phases (from point a34 to point g34 in Figure 34). The liquid phase refrigerant flowing out of the receiver 15 flows into the cooling flow control valve 16c where it is depressurized (from point g34 to point k34 in Figure 34). The refrigerant depressurized by the cooling flow control valve 16c flows into the refrigerant passage of the chiller 20.

[0386] In hot gas heating mode, the low-temperature heat transfer fluid pump 31 is stopped, so the refrigerant flowing into the chiller 20 is drawn into the refrigerant suction port 721 of the ejector 70 without exchanging heat with the low-temperature heat transfer fluid (from point k34 to region P34 in Figure 34).

[0387] Here, the region P shown by dot hatching in Figure 34 represents the state of the refrigerant inside the ejector 70. Inside the ejector 70 in suction mode, there is a refrigerant in a non-equilibrium state, making it difficult to clearly indicate the degree of dryness and superheating. For this reason, in Figure 34, the state of the refrigerant inside the ejector 70 is not shown by dots, but by an approximate region. This is also true for the regions P in other Mollier diagrams.

[0388] Furthermore, the other refrigerant branched off at the first three-way joint 13a flows into the bypass passage 21c and is depressurized by the bypass-side flow control valve 16d. The refrigerant depressurized by the bypass-side flow control valve 16d flows into the nozzle section 71 of the ejector 70 and is depressurized further (from point a34 to region P34 in Figure 34).

[0389] Here, the thin dashed arrow from point a34 in Figure 34 to region P34 represents the ideal decompression process, combining the decompression process of the refrigerant at the bypass-side flow control valve 16d and the decompression process of the refrigerant at the nozzle section 71. This is also true in the Mollier diagram below.

[0390] Inside the ejector 70, the relatively high-enthalpy injected refrigerant sprayed from the nozzle 71 and the relatively low-enthalpy suctioned refrigerant drawn in from the refrigerant suction port 721 merge in the mixing and pressurizing section 722. The mixed refrigerant is then pressurized by the shock wave generated in the mixing and pressurizing section 722. As a result, the refrigerant flowing out of the refrigerant outlet 723 of the ejector 70 (point s34 in Figure 34) becomes a superheated gaseous refrigerant.

[0391] The refrigerant that flows out from the refrigerant outlet 723 is drawn into the compressor 11 and compressed again (from point s34 to point a34 in Figure 34).

[0392] In the hot gas heating mode, the indoor air conditioning unit 40, similar to the outside air intake heating mode, blown air that has been mixed and temperature-adjusted in the mixing space 46 is blown through openings to appropriate locations within the vehicle interior. This achieves heating of the vehicle interior.

[0393] In hot gas heating mode, the ejector 70 is used in suction mode, so the refrigerant flowing out from the refrigerant outlet 723 of the ejector 70 can be a gaseous refrigerant with a superheated degree that has reached equilibrium. Furthermore, the pressure-boosting effect of the shock wave can raise the refrigerant pressure at the refrigerant outlet 723 above the refrigerant pressure at the refrigerant suction port 721.

[0394] Therefore, in hot gas heating mode, the heating capacity of the blown air can be rapidly improved.

[0395] Furthermore, in suction mode, the suction action caused by the expansion wave can bring the refrigerant flow path communicating with the refrigerant suction port 721 closer to a vacuum state. Therefore, in hot gas heating mode, the inside of the outdoor heat exchanger 18 and the indoor evaporator 19 communicating with the refrigerant suction port 721 can be brought closer to a vacuum state.

[0396] (m) Hot gas waste heat heating mode The hot gas waste heat heating mode is activated when the operating conditions for selecting the hot gas heating mode are met, and both the battery-side coolant temperature TWB and the equipment-side coolant temperature TWM are higher than the second reference absorption temperature KTWE2. The second reference absorption temperature KTWE2 is set to a value higher than the lowest saturation temperature that the refrigerant can reach after its pressure is reduced by the suction action of the ejector 70.

[0397] In the heat pump cycle 10 of the hot gas waste heat heating mode, the control device 50 opens the first on-off valve 14a, closes the second on-off valve 14b, and opens the third on-off valve 14c. The control device 50 also closes the heating flow control valve 16a, closes the cooling flow control valve 16b, throttles the cooling flow control valve 16c, and throttles the bypass flow control valve 16d.

[0398] Therefore, in the heat pump cycle 10 of the hot gas waste heat heating mode, the refrigerant circuit is switched to one in which the refrigerant circulates in the same order as in the hot gas heating mode, as shown by the black-filled arrow in Figure 33. Accordingly, the mode of use of the ejector 70 in the hot gas waste heat heating mode is suction mode.

[0399] Furthermore, the control device 50 controls the operation of the compressor 11 and other components, similar to the hot gas heating mode.

[0400] In the low-temperature heat transfer medium circuit 30 of the hot gas waste heat heating mode, the control device 50 operates the low-temperature heat transfer medium pump 31 to achieve a predetermined standard pumping capacity. The control device 50 also controls the opening degrees of the first heat transfer medium flow rate control valve 36a to the third heat transfer medium flow rate control valve 36c to achieve a predetermined opening degree for the hot gas waste heat heating mode. Consequently, in the low-temperature heat transfer medium circuit 30, the low-temperature heat transfer medium circulates as shown by the dashed arrows.

[0401] In the indoor air conditioning unit 40 operating in hot gas waste heat heating mode, the control device 50 controls the operation of various controlled devices, similar to the hot gas heating mode. Furthermore, the control device 50 appropriately controls the operation of other controlled devices.

[0402] Therefore, in the heat pump cycle 10 of the hot gas waste heat heating mode, the state of the refrigerant changes as shown in the Mollier diagram in Figure 35.

[0403] In other words, the flow of refrigerant discharged from the compressor 11 (point a35 in Figure 35) is branched at the first three-way joint 13a. One of the refrigerant branches off at the first three-way joint 13a flows into the indoor condenser 12. The refrigerant that flows into the indoor condenser 12 condenses by releasing heat into the blown air according to the opening of the air mix door 44, similar to the hot gas heating mode. As a result, the blown air is heated in the indoor condenser 12.

[0404] The refrigerant flowing out of the indoor condenser 12 flows into the receiver 15 where it is separated into gas and liquid phases (from point a35 to point g35 in Figure 35). The liquid phase refrigerant flowing out of the receiver 15 flows into the cooling flow control valve 16c where it is depressurized (from point g35 to point k35 in Figure 35). The refrigerant depressurized by the cooling flow control valve 16c flows into the refrigerant passage of the chiller 20. The refrigerant flowing into the chiller 20 absorbs heat from the low-temperature heat transfer medium and evaporates (from point k35 to region P35 in Figure 35).

[0405] Furthermore, the other refrigerant branched off at the first three-way joint 13a flows into the nozzle section 71 of the ejector 70 via the bypass flow control valve 16d, similar to the hot gas heating mode, and is depressurized (from point a35 to region P35 in Figure 35).

[0406] Inside the ejector 70, similar to the hot gas heating mode, the injected refrigerant sprayed from the nozzle section 71 and the suctioned refrigerant drawn in from the refrigerant suction port 721 merge in the mixing and pressurizing section 722. The mixed refrigerant is then pressurized by the shock wave generated in the mixing and pressurizing section 722. As a result, the refrigerant flowing out of the refrigerant outlet 723 of the ejector 70 (point s35 in Figure 35) becomes a superheated gaseous refrigerant.

[0407] The refrigerant that flows out from the refrigerant outlet 723 is drawn into the compressor 11 and compressed again (from point s35 to point a35 in Figure 35).

[0408] Inside the ejector 70, the relatively high-enthalpy injected refrigerant sprayed from the nozzle section 71 and the relatively low-enthalpy suctioned refrigerant drawn in from the refrigerant suction port 721 merge in the mixing and pressurizing section 722. The mixed refrigerant is then pressurized by the shock wave generated in the mixing and pressurizing section 722. As a result, the refrigerant flowing out from the refrigerant outlet 723 (point s34 in Figure 34) becomes a superheated gaseous refrigerant.

[0409] The refrigerant that flows out from the refrigerant outlet 723 is drawn into the compressor 11 and compressed again (from point s34 to point a34 in Figure 34).

[0410] In the low-temperature heat transfer medium circuit 30 of the hot gas waste heat heating mode, the low-temperature heat transfer medium circulates, similar to the battery-only cooling mode.

[0411] In the hot gas waste heat heating mode, the indoor air conditioning unit 40, similar to the hot gas heating mode, blown air that has been mixed and temperature-controlled in the mixing space 46 is blown through openings to appropriate locations in the vehicle interior. This achieves heating of the vehicle interior.

[0412] Therefore, in the hot gas waste heat heating mode, the heating capacity of the blown air can be rapidly improved, similar to the hot gas heating mode.

[0413] Furthermore, in the hot gas waste heat heating mode, similar to the hot gas heating mode, the inside of the indoor evaporator 19, which is connected to the refrigerant suction port 721, can be brought close to a vacuum state. Also, in the hot gas waste heat heating mode, the chiller 20 can absorb the heat from the low-temperature heat transfer medium into the refrigerant, which can then be used as a heat source to heat the blown air in the indoor condenser 12.

[0414] In this case, if the hot gas start mode is selected and both the battery-side coolant temperature TWB and the equipment-side coolant temperature TWM are higher than the reference heat absorption temperature KTWE, the hot gas waste heat heating mode may be used as the operating mode for warming up. If the hot gas waste heat heating mode is used as the operating mode for warming up, the indoor fan 42 should be stopped.

[0415] (n) Hot gas outside air heat absorption heating mode The hot gas outside air intake heating mode is selected when the outside temperature Tam is equal to or greater than the reference extremely low outside temperature KTam1, under operating conditions where the hot gas heating mode is selected. The reference extremely low outside temperature KTam1 is set to a value higher than the lowest saturation temperature that the refrigerant can reach after its pressure has been reduced by the suction action of the ejector 70.

[0416] In the heat pump cycle 10 of the hot gas outside air intake heating mode, the control device 50 opens the first on-off valve 14a, closes the second on-off valve 14b, and opens the third on-off valve 14c. In addition, the control device 50 sets the heating flow control valve 16a to a throttled state, the cooling flow control valve 16b to a fully closed state, the cooling flow control valve 16c to a fully closed state, and the bypass side flow control valve 16d to a throttled state.

[0417] Therefore, in the hot gas outside air heat absorption heating mode heat pump cycle 10, as shown by the black arrows in Figure 36, the refrigerant discharged from the compressor 11 is switched to a refrigerant circuit in which it flows in the following order: indoor condenser 12, receiver 15, heating flow control valve 16a, outdoor heat exchanger 18, and refrigerant suction port 721 of the ejector 70. At the same time, the refrigerant discharged from the compressor 11 is switched to a refrigerant circuit in which it flows in the following order: bypass-side flow control valve 16d located in the bypass passage 21c, and nozzle portion 71 of the ejector 70, and the refrigerant that flows out from the refrigerant outlet 723 of the ejector 70 is drawn into the compressor 11. Thus, the mode of use of the ejector 70 in the hot gas outside air heat absorption heating mode is the suction mode.

[0418] Furthermore, the control device 50 controls the operation of the compressor 11 and other components, similar to the hot gas heating mode.

[0419] In the low-temperature side heat transfer medium circuit 30 of the hot gas outside air heat intake heating mode, the control device 50 stops the low-temperature side heat transfer medium pump 31.

[0420] In the indoor air conditioning unit 40 operating in hot gas outside air intake heating mode, the control device 50 controls the operation of various controlled devices, similar to the hot gas heating mode. Furthermore, the control device 50 appropriately controls the operation of other controlled devices.

[0421] Therefore, in the heat pump cycle 10 of the hot gas outside air intake heating mode, the state of the refrigerant changes as shown in the Mollier diagram in Figure 37.

[0422] In other words, the flow of refrigerant discharged from the compressor 11 (point a37 in Figure 37) is branched at the first three-way joint 13a. One of the refrigerants branched at the first three-way joint 13a flows into the indoor condenser 12. The refrigerant that flows into the indoor condenser 12 condenses by releasing heat into the blown air according to the opening of the air mix door 44, similar to the hot gas heating mode. As a result, the blown air is heated in the indoor condenser 12.

[0423] The refrigerant flowing out of the indoor condenser 12 flows into the receiver 15 where it is separated into gas and liquid phases (from point a37 to point g37 in Figure 37). The liquid phase refrigerant flowing out of the receiver 15 flows into the heating flow control valve 16a where it is depressurized (from point g37 to point d37 in Figure 37). The refrigerant depressurized by the heating flow control valve 16a flows into the outdoor heat exchanger 18. The refrigerant flowing into the outdoor heat exchanger 18 absorbs heat from the outside air and evaporates (from point d37 to region P37 in Figure 37).

[0424] Furthermore, the other refrigerant branched off at the first three-way joint 13a flows into the nozzle section 71 of the ejector 70 via the bypass flow control valve 16d, similar to the hot gas heating mode, and is depressurized (from point a37 to region P37 in Figure 37).

[0425] Inside the ejector 70, similar to the hot gas heating mode, the injected refrigerant sprayed from the nozzle 71 and the suctioned refrigerant drawn in from the refrigerant suction port 721 merge in the mixing and pressurizing section 722. The shock wave generated in the mixing and pressurizing section 722 then pressurizes the mixed refrigerant. As a result, the refrigerant flowing out of the refrigerant outlet 723 of the ejector 70 (point s37 in Figure 37) becomes a superheated gaseous refrigerant.

[0426] The refrigerant that flows out from the refrigerant outlet 723 is drawn into the compressor 11 and compressed again (from point s37 to point a37 in Figure 37).

[0427] In the hot gas outside air intake heating mode, the indoor air conditioning unit 40, similar to the hot gas heating mode, blown air that has been mixed and temperature-adjusted in the mixing space 46 is blown through openings to appropriate locations in the vehicle interior. This achieves heating of the vehicle interior.

[0428] Therefore, in the hot gas outside air intake heating mode, the heating capacity of the blown air can be rapidly improved, similar to the hot gas heating mode.

[0429] Furthermore, in the hot gas outside air heat absorption heating mode, the inside of the indoor evaporator 19, which is connected to the refrigerant suction port 721, and the inside of the refrigerant passage of the chiller 20 can be brought close to a vacuum state. In addition, in the hot gas outside air heat absorption heating mode, the heat contained in the outside air is absorbed by the refrigerant in the outdoor heat exchanger 18 and can be used as a heat source to heat the blown air in the indoor condenser 12.

[0430] (o) Hot gas parallel dehumidification heating mode The hot gas parallel dehumidifying heating mode is selected when dehumidifying heating of the vehicle interior is required under operating conditions where the hot gas heating mode is selected.

[0431] In the hot gas parallel dehumidification heating mode heat pump cycle 10, the control device 50 opens the first on-off valve 14a, closes the second on-off valve 14b, and closes the third on-off valve 14c. The control device 50 also closes the heating flow control valve 16a completely, throttles the cooling flow control valve 16b, throttles the cooling flow control valve 16c, and throttles the bypass flow control valve 16d.

[0432] Therefore, in the hot gas parallel dehumidification heating mode heat pump cycle 10, as shown by the black arrows in Figure 38, the refrigerant discharged from the compressor 11 is switched to a refrigerant circuit in which it flows in the following order: indoor condenser 12, receiver 15, cooling flow control valve 16b, indoor evaporator 19, and refrigerant suction port 721 of the ejector 70. At the same time, the refrigerant discharged from the compressor 11 is switched to a refrigerant circuit in which it flows in the following order: indoor condenser 12, receiver 15, cooling flow control valve 16c, chiller 20, and refrigerant suction port 721 of the ejector 70. Furthermore, the refrigerant discharged from the compressor 11 flows in the following order: bypass-side flow control valve 16d located in the bypass passage 21c, and nozzle section 71 of the ejector 70, and the refrigerant that flows out from the refrigerant outlet 723 of the ejector 70 is drawn into the compressor 11.

[0433] In other words, in the hot gas parallel dehumidification heating mode heat pump cycle 10, the refrigerant circuit is switched to one in which the outdoor heat exchanger 18 and chiller 20 are connected in parallel to the flow of refrigerant discharged from the receiver 15. Furthermore, the ejector 70 is used in suction mode in the hot gas parallel dehumidification heating mode.

[0434] Furthermore, the control device 50 controls the operation of the compressor 11 and other components, similar to the hot gas heating mode. The control device 50 also controls the throttle opening of the cooling flow control valve 16b so that the airflow can be dehumidified within a range that suppresses frost formation on the indoor evaporator 19.

[0435] In the low-temperature side heat transfer medium circuit 30 of the hot gas parallel dehumidification heating mode, the control device 50 stops the low-temperature side heat transfer medium pump 31.

[0436] In the indoor air conditioning unit 40 operating in hot gas parallel dehumidification heating mode, the control device 50 controls the operation of various controlled devices, similar to the hot gas heating mode. Furthermore, the control device 50 appropriately controls the operation of other controlled devices.

[0437] Therefore, in the heat pump cycle 10 of the hot gas parallel dehumidification heating mode, the state of the refrigerant changes as shown in the Mollier diagram in Figure 39. That is, the flow of refrigerant discharged from the compressor 11 (point a39 in Figure 39) is branched at the first three-way joint 13a. One of the refrigerants branched at the first three-way joint 13a flows into the indoor condenser 12.

[0438] The refrigerant flowing into the indoor condenser 12 condenses by releasing heat into the blown air according to the opening degree of the air mix door 44. As a result, the blown air is heated in the indoor condenser 12. The refrigerant flowing out of the indoor condenser 12 flows into the receiver 15 where it is separated into gas and liquid phases (from point a39 to point g39 in Figure 39). The flow of liquid phase refrigerant flowing out of the receiver 15 is branched at the eighth three-way joint 13h.

[0439] One of the refrigerants, branched off at the eighth three-way joint 13h, flows into the cooling flow control valve 16b and is depressurized (from point g39 to point i39 in Figure 39). The refrigerant, depressurized in the cooling flow control valve 16b, flows into the indoor evaporator 19. The refrigerant flowing into the indoor evaporator 19 absorbs heat from the blown air and evaporates. As a result, the blown air is cooled and dehumidified in the indoor evaporator 19. The refrigerant flowing out of the indoor evaporator 19 is drawn into the refrigerant suction port 721 of the ejector 70 (from point i39 to region P39 in Figure 39).

[0440] The refrigerant that is separated at the eighth three-way joint 13h flows into the cooling flow control valve 16c and is depressurized (from point g39 to point k39 in Figure 39). The refrigerant depressurized at the cooling flow control valve 16c flows into the refrigerant passage of the chiller 20. The refrigerant that has flowed into the chiller 20 is drawn into the refrigerant suction port 721 of the ejector 70, similar to the hot gas heating mode (from point k39 to region P39 in Figure 39).

[0441] The other refrigerant, branched off at the first three-way joint 13a, flows into the bypass passage 21c and is depressurized by the bypass-side flow control valve 16d. The refrigerant depressurized by the bypass-side flow control valve 16d flows into the nozzle section 71 of the ejector 70 and is depressurized there (from point a39 in Figure 39 to region P39).

[0442] Inside the ejector 70, similar to the hot gas heating mode, the injected refrigerant sprayed from the nozzle 71 and the suctioned refrigerant drawn in from the refrigerant suction port 721 merge in the mixing and pressurizing unit 722. The mixed refrigerant is then pressurized by the shock wave generated in the mixing and pressurizing unit 722. The refrigerant that flows out from the refrigerant outlet 723 of the ejector 70 (point s39 in Figure 39) is drawn into the compressor 11 and compressed again (from point s39 to point a39 in Figure 39).

[0443] Inside the ejector 70, similar to the hot gas heating mode, the injected refrigerant sprayed from the nozzle 71 and the suctioned refrigerant drawn in from the refrigerant suction port 721 merge in the mixing and pressurizing unit 722. The mixed refrigerant is then pressurized by the shock wave generated in the mixing and pressurizing unit 722. As a result, the refrigerant flowing out of the refrigerant outlet 723 of the ejector 70 (point s39 in Figure 39) becomes a superheated gaseous refrigerant.

[0444] The refrigerant that flows out from the refrigerant outlet 723 is drawn into the compressor 11 and compressed again (from point s39 to point a39 in Figure 39).

[0445] In the hot gas parallel dehumidification heating mode, the indoor air conditioning unit 40, similar to the outside air heat absorption parallel dehumidification heating mode, blown air that has been mixed and temperature-adjusted in the mixing space 46 is blown out through openings to appropriate locations in the vehicle interior. This achieves dehumidification and heating of the vehicle interior.

[0446] In the hot gas parallel dehumidification heating mode, the heating capacity of the blown air can be rapidly improved, similar to the hot gas heating mode.

[0447] Furthermore, although this embodiment describes an example in which the third on-off valve 14c is closed, opening the third on-off valve 14c during hot gas parallel dehumidification heating mode can bring the inside of the outdoor heat exchanger 18, which is in communication with the refrigerant suction port 721, closer to a vacuum state. (p) Hot gas defrost heating mode The hot gas defrost heating mode is an operating mode that defrosts the outdoor heat exchanger 18 when the outside temperature is extremely low. When the outside temperature is extremely low, it may not be possible to complete the defrosting of the outdoor heat exchanger 18 even if the refrigerant circuit is switched to the same mode as the outside air heat absorption heating mode. Therefore, in the hot gas defrost heating mode, the heat generated by the compression work of the compressor 11 is used to melt the frost on the outdoor heat exchanger 18 and perform defrosting.

[0448] In the heat pump cycle 10 of the hot gas defrost heating mode, the control device 50 closes the first on-off valve 14a, opens the second on-off valve 14b, and closes the third on-off valve 14c. In addition, the control device 50 fully opens the heating flow control valve 16a, fully closes the cooling flow control valve 16b, throttles the cooling flow control valve 16c, and throttles the bypass side flow control valve 16d.

[0449] Therefore, in the heat pump cycle 10 of the hot gas defrost heating mode, as shown by the black arrows in Figure 40, the refrigerant discharged from the compressor 11 is switched to a refrigerant circuit in which it flows in the following order: indoor condenser 12, outdoor heat exchanger 18, receiver 15, cooling flow control valve 16c, chiller 20, and refrigerant suction port 721 of the ejector 70. At the same time, the refrigerant discharged from the compressor 11 is switched to a refrigerant circuit in which it flows in the following order: bypass-side flow control valve 16d located in the bypass passage 21c, and nozzle section 71 of the ejector 70, and the refrigerant that flows out from the refrigerant outlet 723 of the ejector 70 is drawn into the compressor 11. Thus, the mode of use of the ejector 70 in the hot gas defrost heating mode is suction mode.

[0450] Furthermore, the control device 50 controls the refrigerant discharge capacity of the compressor 11 to achieve a predetermined refrigerant discharge capacity for hot gas defrosting. In addition, the control device 50 controls the throttle opening of the cooling flow control valve 16c and the bypass side flow control valve 16d, similar to the hot gas heating mode.

[0451] In the low-temperature side heat transfer medium circuit 30 of the hot gas defrost heating mode, the control device 50 stops the low-temperature side heat transfer medium pump 31.

[0452] In the indoor air conditioning unit 40 operating in hot gas defrost heating mode, the control device 50 controls the operation of various controlled devices, similar to the hot gas heating mode. Furthermore, the control device 50 appropriately controls the operation of other controlled devices.

[0453] Therefore, in the heat pump cycle 10 of the hot gas defrost heating mode, the state of the refrigerant changes as shown in the Mollier diagram in Figure 41. That is, the refrigerant discharged from the compressor 11 (point a41 in Figure 41) flows into the indoor condenser 12. The refrigerant that flows into the indoor condenser 12 condenses by releasing heat into the blown air according to the opening degree of the air mix door 44 (from point a41 to point b41 in Figure 41). As a result, the blown air is heated in the indoor condenser 12.

[0454] The refrigerant flowing out of the indoor condenser 12 flows into the outdoor heat exchanger 18 via the fully open heating flow control valve 16a. The refrigerant flowing into the outdoor heat exchanger 18 condenses upon releasing heat. This melts the frost on the outdoor heat exchanger 18, thus defrosting the outdoor heat exchanger 18. The refrigerant flowing out of the outdoor heat exchanger 18 flows into the receiver 15 where it undergoes gas-liquid separation (from point b41 to point g41 in Figure 41).

[0455] Other operations are the same as in the hot gas heating mode. Therefore, in the hot gas defrost heating mode, heating of the vehicle interior can be achieved in the same way as in the hot gas heating mode, and the heat generated by the compression work of the compressor 11 can be used to defrost the outdoor heat exchanger 18.

[0456] As described above, the vehicle air conditioning system 1 of this embodiment can provide comfortable air conditioning inside the vehicle and appropriate temperature control for in-vehicle equipment by switching the operating mode.

[0457] In this embodiment, the vehicle air conditioning system 1 can perform a hot gas heating mode when the outside temperature is extremely low. As mentioned above, in the hot gas heating mode, the blown air is heated mainly using the heat generated by the compression work of the compressor 11. Therefore, in order to quickly improve the heating capacity in the hot gas heating mode, it is effective to increase the intake refrigerant pressure Ps to increase the density of the intake refrigerant.

[0458] In contrast, the vehicle air conditioning system 1 of this embodiment includes an ejector 70 in the heat pump cycle 10. The ejector 70 can raise the refrigerant pressure at the refrigerant outlet 723 to a level higher than the refrigerant pressure at the refrigerant suction port 721, for example, when in hot gas heating mode.

[0459] Therefore, the intake refrigerant pressure Ps can be increased by the pressure-boosting action of the ejector 70 without having to use the heat generated by the compression work of the compressor 11 to raise the temperature of the refrigerant. As a result, the indoor condenser 12, which is the heating unit, can quickly exert sufficient heating capacity. In other words, according to the vehicle air conditioning system 1 of this embodiment, highly effective heating can be achieved even at extremely low outside temperatures.

[0460] Furthermore, a mixing section 722a is formed in the body portion 72 of the ejector 70 in this embodiment. More specifically, the mixing section 722a is formed as a cylindrical space, and the mixing section distance L is set to satisfy the above-mentioned formulas F1 and F2. This allows the refrigerant flowing out from the mixing section 722a to approach an equilibrium state. Then, the refrigerant that has approached an equilibrium state can be discharged from the refrigerant outlet 723 of the ejector 70.

[0461] Furthermore, in the vehicle air conditioning system 1 of this embodiment, the throttle opening of the cooling flow control valve 16c, which is the heating section side flow control unit, is controlled so that the superheat SHS of the inhaled refrigerant approaches the reference superheat KSH when in hot gas operation mode, etc. In other words, in the vehicle air conditioning system 1, the throttle opening of the heating section side flow control unit is adjusted so that the refrigerant flowing out from the refrigerant outlet 723 of the ejector 70 becomes a gaseous refrigerant with a superheat.

[0462] According to this, the intake pressure sensor 52h and the intake temperature sensor 52i can detect the intake refrigerant temperature Ts and intake refrigerant pressure Ps of the intake refrigerant as it approaches equilibrium. Therefore, the control device 50 can accurately detect the superheat level SHS of the intake refrigerant and accurately bring the superheat level SHS of the intake refrigerant closer to the reference superheat level KSH. In other words, liquid compression of the compressor 11 can be accurately prevented.

[0463] In this case, such as during hot gas operation mode, the specific enthalpy (in other words, the degree of dryness or superheat) of the suction refrigerant in equilibrium state is determined by the flow rate ratio of the injected refrigerant flow rate Gd to the suction refrigerant flow rate Gs. Therefore, in the case of hot gas operation mode, the refrigerant that has flowed out of the mixing section 722a and is approaching equilibrium state becomes a gaseous refrigerant with a degree of superheat.

[0464] Furthermore, the vehicle air conditioning system 1 of this embodiment has a suction mode as one of the modes of use for the ejector 70. When the ejector 70 is used in suction mode, such as in the hot gas heating mode, the throttle opening of the bypass-side flow control valve 16d is controlled so that the injected refrigerant is in a state of insufficient expansion.

[0465] According to this, a shock wave is generated within the mixing section 722a, and the refrigerant pressure-boosting effect of the shock wave brings the ejector 70 closer to its maximum pressure state. In other words, the suction refrigerant pressure of the refrigerant flowing out from the refrigerant outlet 723 of the ejector 70 and being drawn into the compressor 11 can be effectively increased. As a result, the suction refrigerant pressure Ps can be increased, and the heating capacity of the blown air in the indoor condenser 12, which is the heating section, can be effectively improved.

[0466] Furthermore, the boosting effect of the ejector 70 reduces the rotational speed of the compressor 11, thereby reducing the operating noise and vibration of the compressor 11.

[0467] Furthermore, the vehicle air conditioning system 1 of this embodiment has a nozzle mode as one of the modes of use for the ejector 70. In addition, as described in the hot gas startup mode, the ejector 70 is used in nozzle mode when the compressor 11 is started, and the throttle opening of the bypass-side flow control valve 16d is controlled so that the injected refrigerant becomes over-expanded.

[0468] According to this, a shock wave is generated in the refrigerant passage of the nozzle section 71, and the refrigerant pressure can be increased by the refrigerant pressure-boosting effect of the shock wave. Therefore, the suction refrigerant pressure PS can be rapidly increased, allowing the system to switch to hot gas heating mode.

[0469] Furthermore, the vehicle air conditioning system 1 of this embodiment is equipped with a suction-side heat exchange unit that exchanges heat between the refrigerant and the object to be heat exchanged. When the ejector 70 is in suction mode, the refrigerant in the suction-side heat exchange unit is drawn in through the refrigerant suction port 721 of the ejector 70.

[0470] According to this, the inside of the suction-side heat exchanger can be brought close to a vacuum state, and the refrigerant and refrigeration oil remaining in the suction-side heat exchanger can be sucked out from the refrigerant suction port 721 and returned to the compressor 11.

[0471] For example, in hot gas heating mode and hot gas waste heat heating mode, the control device 50 closes the heating flow control valve 16a completely, closes the cooling flow control valve 16b completely, and opens the third on / off valve 14c. Then, it draws the refrigerant from inside the outdoor heat exchanger 18 and the indoor evaporator 19 through the refrigerant suction port 721.

[0472] According to this, the inside of the outdoor heat exchanger 18 and the indoor evaporator 19 can be brought close to a vacuum state, and any refrigerant or refrigeration oil remaining inside the outdoor heat exchanger 18 and the indoor evaporator 19 can be sucked out from the refrigerant suction port 721 and returned to the compressor 11.

[0473] Similarly, in the hot gas outside air intake heating mode, the control device 50 closes the cooling flow control valve 16b and the cooling flow control valve 16c. Then, it draws the refrigerant from the indoor evaporator 19 and chiller 20 through the refrigerant suction port 721.

[0474] According to this, the inside of the indoor evaporator 19 and the chiller 20 can be brought close to a vacuum state, and any refrigerant or refrigeration oil remaining inside the indoor evaporator 19 and the chiller 20 can be sucked out from the refrigerant suction port 721 and returned to the compressor 11.

[0475] Similarly, in the hot gas parallel dehumidification heating mode, the control device 50 can close the heating flow rate adjustment valve 16a completely and open the third on / off valve 14c, thereby bringing the inside of the outdoor heat exchanger 18 closer to a vacuum state. This allows any refrigerant or refrigeration oil remaining in the outdoor heat exchanger 18 to be sucked back to the compressor 11 through the refrigerant suction port 721.

[0476] Furthermore, the vehicle air conditioning system 1 of this embodiment is equipped with a suction-side heat exchange unit that exchanges heat between the refrigerant, which has been depressurized in the heating-side flow rate adjustment unit, and the object to be heated. In the operating mode in which the ejector 70 is used in suction mode, the suction-side heat exchange unit can heat the blown air, which is the object to be heated, using the heat absorbed by the refrigerant from the object to be heated as a heat source.

[0477] For example, in the chiller 20 operating in hot gas waste heat heating mode, the cooling flow control valve 16c, which is the flow rate adjustment unit on the heating side, performs heat exchange with the low-temperature side heat transfer medium, which is the object to be heat exchanged. Then, the heat absorbed by the refrigerant from the low-temperature side heat transfer medium by the chiller 20 is used as a heat source to heat the blown air in the indoor condenser 12.

[0478] Similarly, in the outdoor heat exchanger 18 of the hot gas outdoor air heat absorption heating mode, the indoor condenser 12 can heat the blown air using the heat absorbed from the outside air, which is the heat exchange target, and the refrigerant whose pressure has been reduced by the heating flow control valve 16a, which is the heating section side flow rate adjustment section, as the heat source.

[0479] Similarly, in the indoor evaporator 19 of the hot gas parallel dehumidification heating mode, the indoor condenser 12 can heat the blown air using the refrigerant, which has been depressurized by the cooling flow control valve 16b (which is the flow rate adjustment unit on the heating unit side), and the heat absorbed from the outside air, which is the object of heat exchange, as the heat source.

[0480] Furthermore, in the vehicle air conditioning system 1 of this embodiment, when the ejector 70 is used in suction mode in hot gas operation mode, the refrigerant discharge capacity of the compressor 11 is controlled so that the evaporator-side refrigerant temperature Te of the indoor evaporator 19, which is the suction-side heat exchange unit, becomes higher than the reference lower limit temperature KTem. This suppresses the deterioration of sealing materials used in pipe connections and the like, and ensures sealing performance.

[0481] (Second Embodiment) In the vehicle air conditioning system 1 of this embodiment, a variable nozzle type ejector 70a is employed, as shown in the overall configuration diagram of Figure 42. With the variable nozzle type ejector 70a, the flow rate of refrigerant flowing from the bypass passage 21c to the nozzle section 71 can be adjusted by changing the cross-sectional area of ​​the refrigerant passage in the nozzle section 71. For this reason, the bypass side flow control valve 16d is eliminated in this embodiment.

[0482] The detailed configuration of the ejector 70a will be explained using Figure 43. The ejector 70a has a nozzle section 71, a body section 72, and a flow rate adjustment section 73. The flow rate adjustment section 73 has a needle valve 73a and a drive mechanism 73b.

[0483] The needle valve 73a changes the passage cross-sectional area of ​​the throat portion 713 and the injection port 715 of the nozzle portion 71 by being displaced in the axial direction of the nozzle portion 71. The needle valve 73a is formed of a needle-shaped member made of metal (stainless steel in this embodiment). The central axis of the needle valve 73a is arranged coaxially with the central axis of the nozzle portion 71. The end of the needle valve 73a opposite the injection port 715 is connected to the drive mechanism 73b.

[0484] The drive mechanism 73b is a drive unit that displaces the needle valve 73a in the central axis direction (i.e., the Z axis direction). In this embodiment, a stepping motor is used as the drive mechanism 73b. The operation of the drive mechanism 73b is controlled by a control signal (i.e., a control pulse) output from the control device 50.

[0485] Therefore, the ejector 70a corresponds to a configuration in which the ejector and the bypass-side flow rate adjustment unit are integrated. In other words, the flow rate adjustment unit 73, which is the bypass-side flow rate adjustment unit in this embodiment, adjusts the flow rate of refrigerant flowing from the bypass passage 21c to the nozzle portion 71 by changing the passage cross-sectional area of ​​the refrigerant passage formed in the nozzle portion 71 of the ejector 70a. The other configurations of the ejector 70a are the same as those of the ejector 70 described in the first embodiment.

[0486] Therefore, even with a vehicle air conditioning system equipped with an ejector 70a, the same effects as in the first embodiment can be obtained. That is, in the operating mode performed at extremely low ambient temperatures, the refrigerant pressure boosting action of the ejector 70a rapidly increases the intake refrigerant pressure Ps, thereby achieving highly immediate heating.

[0487] Furthermore, since this embodiment employs a variable nozzle type ejector 70a, the refrigerant depressurization process in the nozzle section 71 can be brought closer to isentropic depressurization and expansion than in the first embodiment. Specifically, for example, the actual depressurization process in the nozzle section 71 can be brought closer to the dashed arrow from point a34 to region P34 shown in the Mollier diagram of the hot gas heating mode in Figure 34.

[0488] Therefore, according to the ejector 70a of this embodiment, the energy loss of the refrigerant in the nozzle section 71 can be reduced, and the amount of pressure increased by the ejector 70a can be increased. As a result, more immediate and effective heating can be achieved.

[0489] (Third embodiment) In this embodiment, an example is described in which the heat pump cycle device according to the present invention is applied to a vehicle air conditioning system 1a shown in the overall configuration diagram of Figure 44. The vehicle air conditioning system 1a is an air conditioning system with an on-board equipment temperature control function, similar to that of the first embodiment. The vehicle air conditioning system 1a includes a heat pump cycle 10a, a low-temperature side heat transfer medium circuit 30, a high-temperature side heat transfer medium circuit 60, an indoor air conditioning unit 40, a control device 50, and the like.

[0490] The heat pump cycle 10a adjusts the temperature of the air supplied to the vehicle interior, the low-temperature heat transfer medium circulating in the low-temperature heat transfer medium circuit 30, and the high-temperature heat transfer medium circulating in the high-temperature heat transfer medium circuit 60.

[0491] In the heat pump cycle 10a, compared to the heat pump cycle 10 described in the first embodiment, the indoor condenser 12, heating flow control valve 16a, first on-off valves 14a to third on-off valves 14c, outdoor heat exchanger 18, inlet side passage 21a, outlet side passage 21b, etc., are eliminated.

[0492] Therefore, in the heat pump cycle 10a, the inlet side of the refrigerant passage of the water refrigerant heat exchanger 121 is connected to one outlet of the first three-way joint 13a. The water refrigerant heat exchanger 121 is a heat exchanger that exchanges heat between the discharged refrigerant flowing out from one outlet of the first three-way joint 13a and the high-temperature side heat transfer medium circulating in the high-temperature side heat transfer medium circuit 60. The water refrigerant heat exchanger 121 is a heat dissipation section that releases the heat contained in the discharged refrigerant to the high-temperature side heat transfer medium.

[0493] The outlet of the refrigerant passage of the water refrigerant heat exchanger 121 is connected to the inlet side of the receiver 15. The outlet of the receiver 15 is connected to the inlet side of the eighth three-way joint 13h.

[0494] Next, the high-temperature side heat transfer fluid circuit 60 is a circuit that circulates the high-temperature side heat transfer fluid. In this embodiment, the same type of fluid as the low-temperature side heat transfer fluid is used as the high-temperature side heat transfer fluid. The high-temperature side heat transfer fluid circuit 60 is equipped with a high-temperature side heat transfer fluid pump 61, a heat transfer fluid passage of the water-refrigerant heat exchanger 121, a high-temperature side radiator 62, a heater core 64, and the like.

[0495] The high-temperature side heat transfer fluid pump 61 is a high-temperature side heat transfer fluid pumping unit that draws in the high-temperature side heat transfer fluid and pumps it into the heat transfer fluid passage of the water refrigerant heat exchanger 121. The basic configuration of the high-temperature side heat transfer fluid pump 61 is the same as that of the low-temperature side heat transfer fluid pump 31.

[0496] The outlet of the heat transfer medium passage of the water refrigerant heat exchanger 121 is connected to the inlet side of the first high-temperature side heat transfer medium three-way joint 63a. One outlet of the first high-temperature side heat transfer medium three-way joint 63a is connected to the heat transfer medium inlet side of the heater core 64. The basic configuration of the first high-temperature side heat transfer medium three-way joint 63a is the same as that of the first heat transfer medium three-way joint 33a.

[0497] The heater core 64 is located inside the air conditioning case 41 of the indoor air conditioning unit 40, similar to the indoor condenser 12 described in the first embodiment. The heater core 64 is a heat exchanger that exchanges heat between the high-temperature side heat transfer medium heated in the water refrigerant heat exchanger 121 and the blown air. The heater core 64 is a heat dissipation section that releases the heat contained in the high-temperature side heat transfer medium to the blown air. One inlet side of the second high-temperature side heat transfer medium three-way joint 63b is connected to the heat transfer medium outlet of the heater core 64.

[0498] The other outlet of the first high-temperature side heat transfer medium three-way joint 63a is connected to the inlet side of the high-temperature side heat transfer medium flow rate control valve 66. The basic configuration of the high-temperature side heat transfer medium flow rate control valve 66 is the same as that of the first heat transfer medium flow rate control valve 36a, etc. The outlet of the high-temperature side heat transfer medium flow rate control valve 66 is connected to the inlet side of the high-temperature side radiator 62.

[0499] The high-temperature side radiator 62 is a high-temperature side heat transfer medium and outside air heat exchange unit that exchanges heat between the high-temperature side heat transfer medium and outside air blown by an outside air fan (not shown). The high-temperature side radiator 62 is located on the front side of the drive unit chamber. Therefore, when the vehicle is running, the high-temperature side radiator 62 can be exposed to the airflow from the vehicle. The high-temperature side radiator 62 may be integrally formed with at least one of the low-temperature side radiator 32 and the outdoor heat exchanger 18.

[0500] The outlet of the high-temperature side radiator 62 is connected to the other inlet side of the second high-temperature side heat transfer fluid three-way joint 63b. The outlet of the second high-temperature side heat transfer fluid three-way joint 63b is connected to the suction side of the high-temperature side heat transfer fluid pump 61.

[0501] Therefore, in the high-temperature heat transfer medium circuit 60, by operating the high-temperature heat transfer medium pump 61, the high-temperature heat transfer medium heated in the water-refrigerant heat exchanger 121 can be flowed into the heater core 64. Then, in the heater core 64, heat exchange occurs between the high-temperature heat transfer medium and the blown air, thereby heating the blown air.

[0502] In other words, each component of the water-refrigerant heat exchanger 121 and the high-temperature side heat transfer medium circuit 60 in this embodiment is a heating unit that heats the blown air, which is the object to be heated, using the refrigerant that flows out from one outlet of the first three-way joint 13a as a heat source.

[0503] Furthermore, a high-temperature heat transfer medium temperature sensor 53h is connected to the input side of the control device 50 in this embodiment. The high-temperature heat transfer medium temperature sensor 53h is a high-temperature heat transfer medium temperature detection unit that detects the high-temperature heat transfer medium temperature TWH, which is the temperature of the high-temperature heat transfer medium flowing into the heater core 64. The other configurations of the vehicle air conditioning system 1a are the same as those of the vehicle air conditioning system 1 described in the first embodiment.

[0504] Next, the operation of the vehicle air conditioning system 1a of this embodiment in the above configuration will be described. The vehicle air conditioning system 1a can switch operating modes in the same way as in the first embodiment. Specifically, the operating modes in which the ejector usage mode is aisle mode can be (a) cooling mode, (i) waste heat heating mode, and (j) waste heat parallel dehumidification heating mode.

[0505] Furthermore, the following operating modes can be used, where the ejector is in nozzle mode: (k) hot gas start mode. Additionally, the following operating modes can be used, where the ejector is in suction mode: (l) hot gas heating mode, (m) hot gas waste heat heating mode, and (o) hot gas parallel dehumidification heating mode. Each operating mode is described below.

[0506] (a) Cooling mode In the cooling mode heat pump cycle 10a, the control device 50 sets the cooling flow control valve 16b to a throttled state, the cooling flow control valve 16c to a fully closed state, and the bypass side flow control valve 16d to a fully closed state.

[0507] Therefore, in the cooling mode heat pump cycle 10a, the refrigerant discharged from the compressor 11 is switched to a refrigerant circuit that circulates in the following order: water refrigerant heat exchanger 121, receiver 15, cooling flow control valve 16b, indoor evaporator 19, refrigerant suction port 721 of the ejector 70, then refrigerant outlet 723 of the ejector 70, and finally the suction port of the compressor 11. Consequently, the usage mode of the ejector 70 in cooling mode is the passage mode.

[0508] Furthermore, the control device 50 controls the operation of various controlled devices of the heat pump cycle 10a, similar to the cooling mode in the first embodiment.

[0509] In the high-temperature side heat transfer medium circuit 60 in cooling mode, the control device 50 operates the high-temperature side heat transfer medium pump 61 to exert a predetermined standard pumping capacity.

[0510] Furthermore, the control device 50 controls the throttle opening of the high-temperature side heat medium flow rate control valve 66 so that the high-temperature side heat medium temperature TWH detected by the high-temperature side heat medium temperature sensor 53h is equal to or greater than the reference high-temperature side heat medium temperature KTWH. The reference high-temperature side heat medium temperature KTWH is set to a value that allows the blown air to be heated by the heater core 64.

[0511] In the cooling mode, the low-temperature heat transfer medium circuit 30 controls the operation of various controlled devices in the same manner as in the cooling mode of the first embodiment.

[0512] In the indoor air conditioning unit 40 in cooling mode, the control device 50 controls the operation of various controlled devices, similar to the cooling mode in the first embodiment.

[0513] Therefore, in the cooling mode heat pump cycle 10a, a vapor compression type refrigeration cycle is configured in which the water refrigerant heat exchanger 121 functions as a condenser and the indoor evaporator 19 functions as an evaporator. As a result, the high-temperature side heat transfer medium is heated in the water refrigerant heat exchanger 121, and the blown air is cooled in the indoor evaporator 19.

[0514] In the high-temperature side heat transfer medium circuit 60 in cooling mode, the high-temperature side heat transfer medium heated in the water refrigerant heat exchanger 121 flows into the heater core 64 and the high-temperature side radiator 62 according to the throttle opening of the high-temperature side heat transfer medium flow rate control valve 66.

[0515] The high-temperature heat transfer fluid that flows into the heater core 64 releases heat into the blown air according to the opening degree of the air mix door 44. As a result, the blown air is heated by the heater core 64. The high-temperature heat transfer fluid that flows into the high-temperature radiator 62 releases heat by exchanging heat with the outside air. As a result, the high-temperature heat transfer fluid is cooled.

[0516] In the cooling mode, the low-temperature side heat transfer medium circuit 30 cools the battery 80 and the high-voltage equipment 81, similar to the cooling mode in the first embodiment.

[0517] In the indoor air conditioning unit 40 in cooling mode, the air blown from the indoor fan 42 flows into the indoor evaporator 19 and is cooled. The air cooled in the indoor evaporator 19 flows into the air passage on the heater core 64 side and the cold air bypass passage 45, depending on the opening degree of the air mix door 44.

[0518] The air flowing into the air passage on the heater core 64 side is heated as it passes through the heater core 64 and then flows into the mixing space 46. The air flowing into the cold air bypass passage 45 flows into the mixing space 46 without being heated. The air that is mixed and temperature-controlled in the mixing space 46 is then blown out through the openings to the appropriate locations in the vehicle interior. This provides air conditioning to the vehicle interior.

[0519] (i) Waste heat heating mode In the waste heat heating mode heat pump cycle 10a, the control device 50 closes the cooling flow control valve 16b completely, throttles the cooling flow control valve 16c, and closes the bypass flow control valve 16d completely.

[0520] Therefore, in the heat pump cycle 10a of the outside air heat absorption heating mode, the refrigerant discharged from the compressor 11 is switched to a refrigerant circuit that circulates in the following order: water refrigerant heat exchanger 121, receiver 15, cooling flow control valve 16c, refrigerant passage of chiller 20, refrigerant suction port 721 of ejector 70, refrigerant outlet 723 of ejector 70, and suction port of compressor 11. Accordingly, the mode of use of ejector 70 in the outside air heat absorption waste heat heating mode is the passage mode.

[0521] Furthermore, the control device 50 controls the refrigerant discharge capacity of the compressor 11 so that the high-temperature side heat transfer medium temperature TWH approaches the target high-temperature side heat transfer medium temperature TWHO. The target high-temperature side heat transfer medium temperature TWHO is determined based on the target discharge temperature TAO by referring to a control map pre-stored in the control device 50. In addition, the control device 50 controls the operation of various controlled devices in the heat pump cycle 10a, similar to the waste heat heating mode of the first embodiment.

[0522] In the waste heat heating mode, the high-temperature side heat transfer medium circuit 60 is fully closed by the control device 50. In addition, the control device 50 controls the operation of various other controlled devices, similar to the cooling mode.

[0523] In the low-temperature heat transfer medium circuit 30 of the waste heat heating mode, the control device 50 controls the operation of various controlled devices, similar to the cooling mode.

[0524] In the indoor air conditioning unit 40 operating in waste heat heating mode, the control device 50 controls the operation of various controlled devices, similar to the cooling mode.

[0525] Therefore, in the heat pump cycle 10a of the outside air heat intake waste heat heating mode, a vapor compression type refrigeration cycle is configured in which the water refrigerant heat exchanger 121 functions as a condenser and the chiller 20 functions as an evaporator. As a result, the high-temperature side heat transfer medium is heated in the water refrigerant heat exchanger 121, and the low-temperature side heat transfer medium is cooled in the chiller 20.

[0526] In the high-temperature heat transfer medium circuit 60 of the waste heat heating mode, the blown air is heated by the heater core 64, similar to the cooling mode.

[0527] In the low-temperature heat transfer medium circuit 30 of the waste heat heating mode, the battery 80 and the high-voltage equipment 81 are cooled, similar to the cooling mode.

[0528] In the waste heat heating mode, the interior air conditioning unit 40 blows temperature-controlled air through openings to appropriate locations within the vehicle interior, similar to the cooling mode. This achieves heating within the vehicle interior.

[0529] Furthermore, in the low-temperature side heat transfer medium circuit 30 of the waste heat heating mode, the circuit configuration is switched by the opening pattern of the first heat transfer medium flow rate control valve 36a to the third heat transfer medium flow rate control valve 36c. For example, the low-temperature side heat transfer medium circuit 30 may be switched to a circuit configuration that allows the low-temperature side heat transfer medium to flow into at least one of the cooling water passage 80a of the battery 80 and the cooling water passage 81a of the high-voltage equipment 81.

[0530] In this case, similar to the waste heat heating mode of the first embodiment, the cooling capacity of the heat pump cycle 10a can be used to cool at least one of the battery 80 and the high-voltage equipment 81. Furthermore, the waste heat from at least one of the battery 80 and the high-voltage equipment 81 can be used as a heat source to heat the blown air in the heater core 64.

[0531] Furthermore, the low-temperature side heat transfer medium circuit 30 may be switched to a circuit configuration that allows the low-temperature side heat transfer medium to flow into the low-temperature side radiator 32. In this case, as in the outside air heat absorption heating mode described in the first embodiment, the heat contained in the outside air can be used as a heat source to heat the blown air in the heater core 64.

[0532] (j) Waste heat parallel dehumidification heating mode In the heat pump cycle 10a of the waste heat parallel dehumidification heating mode, the control device 50 sets the cooling flow control valve 16b to a throttled state, the cooling flow control valve 16c to a throttled state, and the bypass side flow control valve 16d to a fully closed state.

[0533] Therefore, in the heat pump cycle 10a of the waste heat parallel dehumidification heating mode, the refrigerant discharged from the compressor 11 is switched to a refrigerant circuit that circulates in the following order: water refrigerant heat exchanger 121, receiver 15, cooling flow control valve 16b, refrigerant passage of indoor evaporator 19, refrigerant suction port 721 of ejector 70, then refrigerant outlet 723 of ejector 70, and finally the suction port of compressor 11. At the same time, the refrigerant discharged from the compressor 11 is switched to a refrigerant circuit that circulates in the following order: water refrigerant heat exchanger 121, receiver 15, cooling flow control valve 16c, refrigerant passage of chiller 20, refrigerant suction port 721 of ejector 70, then refrigerant outlet 723 of ejector 70, and finally the suction port of compressor 11.

[0534] In other words, in the waste heat parallel dehumidification heating mode heat pump cycle 10a, the refrigerant circuit is switched to one in which the indoor evaporator 19 and chiller 20 are connected in parallel to the flow of refrigerant discharged from the receiver 15. Furthermore, the ejector 70 is used in the passage mode in the waste heat parallel dehumidification heating mode.

[0535] Furthermore, the control device 50 controls the operation of various controlled devices in the heat pump cycle 10a, similar to the cooling mode.

[0536] In the high-temperature side heat transfer medium circuit 60 of the waste heat parallel dehumidification heating mode, the control device 50 controls the operation of various controlled devices, similar to the cooling mode.

[0537] In the low-temperature side heat transfer medium circuit 30 of the waste heat parallel dehumidification heating mode, the control device 50 controls the operation of various controlled devices, similar to the cooling mode.

[0538] In the indoor air conditioning unit 40 operating in waste heat parallel dehumidification heating mode, the control device 50 controls the operation of various controlled devices, similar to the cooling mode.

[0539] Therefore, in the waste heat parallel dehumidification heating mode heat pump cycle 10a, a vapor compression type refrigeration cycle is configured in which the water refrigerant heat exchanger 121 functions as a condenser and the indoor evaporator 19 and chiller 20 function as evaporators. As a result, the high-temperature side heat transfer medium is heated in the water refrigerant heat exchanger 121. The blown air is cooled and dehumidified in the indoor evaporator 19. The low-temperature side heat transfer medium is cooled in the chiller 20.

[0540] In the high-temperature side heat transfer medium circuit 60 of the waste heat parallel dehumidification heating mode, the blown air is heated by the heater core 64, similar to the cooling mode.

[0541] In the low-temperature side heat transfer medium circuit 30 of the waste heat parallel dehumidification heating mode, the battery 80 and the high-voltage equipment 81 are cooled, similar to the cooling mode.

[0542] In the waste heat parallel dehumidification heating mode, the indoor air conditioning unit 40 blows temperature-controlled air through openings to appropriate locations within the vehicle interior, similar to the cooling mode. This achieves dehumidification and heating within the vehicle interior.

[0543] (k) Hot gas start mode In the hot gas-started heat pump cycle 10a, the control device 50 closes the cooling flow control valve 16b completely, closes the cooling flow control valve 16c completely, and throttles the bypass flow control valve 16d.

[0544] Therefore, in the hot gas start mode heat pump cycle 10a, the refrigerant circuit is switched to one in which the refrigerant circulates in the same order as in the hot gas start mode of the first embodiment. Accordingly, the usage mode of the ejector 70 in the hot gas start mode is nozzle mode. Other operations are the same as in the first embodiment.

[0545] Therefore, in hot gas startup mode, the suction refrigerant pressure Ps and suction refrigerant temperature Ts can be rapidly increased, similar to the first embodiment.

[0546] (l) Hot gas heating mode In the hot gas heating mode heat pump cycle 10a, the control device 50 closes the cooling flow control valve 16b completely, throttles the cooling flow control valve 16c, and throttles the bypass flow control valve 16d.

[0547] Therefore, in the hot gas heating mode, the heat pump cycle 10a is switched to a refrigerant circuit in which the refrigerant circulates in the same order as in the hot gas heating mode of the first embodiment. Accordingly, the ejector 70 is used in suction mode in the hot gas heating mode. The control device 50 also controls the operation of each component of the heat pump cycle 10a, similar to the hot gas heating mode of the first embodiment.

[0548] In the hot gas heating mode, the high-temperature side heat transfer medium circuit 60 controls the operation of various controlled devices, similar to the waste heat heating mode. Other operations are the same as in the hot gas heating mode of the first embodiment.

[0549] Therefore, in hot gas heating mode, similar to the first embodiment, the heating capacity of the blown air can be rapidly improved to achieve heating inside the vehicle. In addition, in hot gas heating mode, the inside of the indoor evaporator 19, which is in communication with the refrigerant suction port 721, can be brought close to a vacuum state.

[0550] (m) Hot gas waste heat heating mode In the heat pump cycle 10a of the hot gas waste heat heating mode, the control device 50 closes the cooling flow control valve 16b completely, throttles the cooling flow control valve 16c, and throttles the bypass flow control valve 16d.

[0551] Therefore, in the heat pump cycle 10a of the hot gas waste heat heating mode, the refrigerant circuit is switched to one in which the refrigerant circulates in the same order as in the hot gas heating mode. Consequently, the ejector 70 is used in suction mode in the hot gas heating mode. In addition, the control device 50 controls the operation of other controlled equipment in the same way as in the waste heat heating mode.

[0552] Therefore, in the hot gas waste heat heating mode, similar to the first embodiment, the heating capacity of the blown air can be rapidly improved to achieve heating inside the vehicle. In addition, in the hot gas waste heat heating mode, the inside of the indoor evaporator 19, which is connected to the refrigerant suction port 721, can be brought close to a vacuum state. Furthermore, the chiller 20 can absorb the heat from the low-temperature heat transfer medium into the refrigerant, which can then be used as a heat source to heat the blown air in the indoor condenser 12.

[0553] (o) Hot gas parallel dehumidification heating mode In the hot gas parallel dehumidification heating mode heat pump cycle 10a, the control device 50 sets the cooling flow control valve 16b to a throttled state, the cooling flow control valve 16c to a throttled state, and the bypass side flow control valve 16d to a throttled state.

[0554] Therefore, in the heat pump cycle 10a of the hot gas parallel dehumidification heating mode, the refrigerant circuit is switched to one in which the refrigerant circulates in the same order as in the hot gas parallel dehumidification heating mode of the first embodiment. Accordingly, the ejector 70 is used in suction mode in the hot gas parallel dehumidification heating mode. In addition, the control device 50 controls the operation of other controlled equipment in the same way as in the waste heat parallel dehumidification heating mode.

[0555] Therefore, in the hot gas parallel dehumidifying heating mode, similar to the first embodiment, the heating capacity of the blown air can be rapidly improved to achieve dehumidifying heating inside the vehicle.

[0556] As described above, the vehicle air conditioning system 1a of this embodiment can provide comfortable air conditioning inside the vehicle and appropriate temperature control for in-vehicle equipment by switching the operating mode.

[0557] Furthermore, the vehicle air conditioning system 1a of this embodiment can achieve the same effects as the first embodiment. That is, in the operating mode performed at extremely low ambient temperatures, the refrigerant pressure boosting action of the ejector 70 rapidly increases the intake refrigerant pressure Ps, thereby achieving highly immediate heating.

[0558] (Fourth embodiment) In this embodiment, an example is described in which the heat pump cycle device according to the present invention is applied to a vehicle air conditioning system 1b shown in the overall configuration diagram of Figure 45. The vehicle air conditioning system 1b is an air conditioning system with an on-board equipment temperature control function, similar to that of the first embodiment. The vehicle air conditioning system 1b includes a heat pump cycle 10b, a low-temperature side heat transfer medium circuit 30b, an indoor air conditioning unit 40, a control device 50, a high-temperature side heat transfer medium circuit 60, and the like.

[0559] In the heat pump cycle 10b, the cooling flow control valve 16b, indoor evaporator 19, etc., are eliminated compared to the heat pump cycle 10a described in the second embodiment. Therefore, in the heat pump cycle 10b, the inlet side of the cooling flow control valve 16c is connected to the liquid phase refrigerant outlet of the receiver 15.

[0560] In the low-temperature side heat transfer fluid circuit 30b, a fourth heat transfer fluid flow rate control valve 36d and a cooler core 39, etc., are added compared to the low-temperature side heat transfer fluid circuit 30 described in the first embodiment.

[0561] More specifically, in the low-temperature side heat transfer fluid circuit 30b, the inlet side of the fifth heat transfer fluid three-way joint 33e is connected to the other outlet of the second heat transfer fluid three-way joint 33b. The inlet side of the third heat transfer fluid flow control valve 36c is connected to one outlet of the fifth heat transfer fluid three-way joint 33e. In addition, one inlet side of the sixth heat transfer fluid three-way joint 33f is connected to the heat transfer fluid outlet of the low-temperature side radiator 32 in this embodiment.

[0562] The inlet side of the fourth heat transfer fluid flow control valve 36d is connected to the other outlet of the fifth heat transfer fluid three-way joint 33e. The basic configuration of the fourth heat transfer fluid flow control valve 36d is the same as that of the first heat transfer fluid flow control valve 36a, etc.

[0563] The outlet of the fourth heat transfer medium flow control valve 36d is connected to the heat transfer medium inlet side of the cooler core 39. The cooler core 39 is located inside the air conditioning case 41 of the indoor air conditioning unit 40, similar to the indoor evaporator 19 described in the first embodiment. The cooler core 39 is a heat exchanger that exchanges heat between the low-temperature heat transfer medium cooled by the chiller 20 and the blown air. The cooler core 39 is a cooling unit that cools the blown air by causing the low-temperature heat transfer medium to absorb the heat contained in the blown air.

[0564] The outlet of the cooler core 39 is connected to the other inlet side of the sixth heat transfer fluid three-way joint 33f. The outlet of the sixth heat transfer fluid three-way joint 33f is connected to the other inlet side of the third heat transfer fluid three-way joint 33c.

[0565] Furthermore, a chiller temperature sensor 52j and a cooler core cooling water temperature sensor 53c are connected to the input side of the control device 50 in this embodiment. The chiller temperature sensor 52j is a chiller temperature detection unit that detects the chiller-side refrigerant temperature Tc, which is the temperature of the refrigerant in the chiller 20. More specifically, the chiller temperature sensor 52j in this embodiment detects the temperature of the refrigerant on the outlet side of the refrigerant passage of the chiller 20.

[0566] The cooler core coolant temperature sensor 53c is a cooler core coolant temperature detection unit that detects the cooler core side coolant temperature TWC, which is the temperature of the low-temperature side heat transfer medium on the outlet side of the cooler core 39. The other configurations of the vehicle air conditioning system 1b are the same as those of the vehicle air conditioning system 1a described in the third embodiment.

[0567] Next, the operation of the vehicle air conditioning system 1b of this embodiment in the above configuration will be described. The vehicle air conditioning system 1b can switch operating modes in the same way as in the first embodiment. Specifically, the operating modes in which the ejector usage mode is aisle mode can be (a) cooling mode and (i) waste heat heating mode.

[0568] Furthermore, the following operating modes can be used, where the ejector is in nozzle mode: (k) hot gas start mode. Additionally, the following operating modes can be used, where the ejector is in suction mode: (l) hot gas heating mode, (m) hot gas waste heat heating mode, and (o) hot gas parallel dehumidification heating mode. Each operating mode is described below.

[0569] (a) Cooling mode In the cooling mode heat pump cycle 10b, the control device 50 restricts the cooling flow control valve 16c and fully closes the bypass flow control valve 16d.

[0570] Therefore, in the cooling mode heat pump cycle 10b, the refrigerant discharged from the compressor 11 is switched to a refrigerant circuit that circulates in the following order: water refrigerant heat exchanger 121, receiver 15, cooling flow control valve 16c, chiller 20, refrigerant suction port 721 of the ejector 70, then refrigerant outlet 723 of the ejector 70, and finally the suction port of the compressor 11. Consequently, the usage mode of the ejector 70 in cooling mode is the passage mode.

[0571] Furthermore, the control device 50 controls the refrigerant discharge capacity of the compressor 11 so that the chiller-side refrigerant temperature Tc detected by the chiller temperature sensor 52j approaches the target evaporator temperature TEO. In addition, the control device 50 controls the throttle opening of the cooling flow control valve 16c so that the superheat level SHS of the suction refrigerant approaches the reference superheat level KSH.

[0572] In the high-temperature side heat transfer medium circuit 60 of the cooling mode, the control device 50 controls the operation of various controlled devices, similar to the cooling mode of the third embodiment.

[0573] In the cooling mode, the low-temperature side heat transfer medium circuit 30b is operated by the control device 50 to activate the low-temperature side heat transfer medium pump 31 to achieve a predetermined standard pumping capacity.

[0574] Furthermore, the control device 50 determines the opening pattern of the first heat transfer medium flow rate control valve 36a to the fourth heat transfer medium flow rate control valve 36d by referring to a control map pre-stored in the control device 50, based on the battery-side coolant temperature TWB, the equipment-side coolant temperature TWM, and the cooler core-side coolant temperature TWC detected by the cooler core coolant temperature sensor 53c.

[0575] In the control map, similar to the first embodiment, the opening pattern is determined so that the battery-side coolant temperature TWB approaches the reference battery-side coolant temperature KTWB, and the equipment-side coolant temperature TWM approaches the reference equipment-side coolant temperature KTWM. At the same time, the opening pattern is determined so that the cooler core-side coolant temperature TWC approaches the reference cooler core-side coolant temperature KTWC. The reference cooler core-side coolant temperature KTWC is set to a value that allows for adequate cooling of the blown air.

[0576] In the indoor air conditioning unit 40 in cooling mode, the control device 50 controls the operation of various controlled devices, similar to the cooling mode in the third embodiment.

[0577] Therefore, in the cooling mode heat pump cycle 10b, a vapor compression type refrigeration cycle is configured in which the water refrigerant heat exchanger 121 functions as a condenser and the chiller 20 functions as an evaporator. As a result, the high-temperature side heat transfer medium is heated in the water refrigerant heat exchanger 121, and the low-temperature side heat transfer medium is cooled in the chiller 20.

[0578] In the high-temperature side heat transfer medium circuit 60 of the cooling mode, the blown air is heated by the heater core 64, similar to the cooling mode of the third embodiment.

[0579] In the cooling mode, the low-temperature heat transfer medium circuit 30b cools the battery 80 and the high-voltage equipment 81, similar to the cooling battery cooling mode of the first embodiment. Furthermore, the low-temperature heat transfer medium cooled by the chiller 20 flows into the cooler core 39. The low-temperature heat transfer medium that flows into the cooler core 39 exchanges heat with the blown air. As a result, the blown air is cooled.

[0580] In the indoor air conditioning unit 40 in cooling mode, the air blown from the indoor fan 42 flows into the cooler core 39 and is cooled. The air cooled in the cooler core 39 flows into the air passage on the heater core 64 side and the cold air bypass passage 45, depending on the opening degree of the air mix door 44.

[0581] The air flowing into the air passage on the heater core 64 side is heated as it passes through the heater core 64 and then flows into the mixing space 46. The air flowing into the cold air bypass passage 45 flows into the mixing space 46 without being heated. The air that is mixed and temperature-controlled in the mixing space 46 is then blown out through the openings to the appropriate locations in the vehicle interior. This enables cooling or dehumidifying heating of the vehicle interior.

[0582] (i) Waste heat heating mode In the waste heat heating mode heat pump cycle 10b, the control device 50 restricts the cooling flow control valve 16c and fully closes the bypass flow control valve 16d.

[0583] Therefore, in the waste heat heating mode, the heat pump cycle 10b switches to a refrigerant circuit in which the refrigerant circulates in the same order as in the cooling mode. Consequently, the usage mode of the ejector 70 in the waste heat heating mode is the passage mode.

[0584] Furthermore, the control device 50 controls the operation of various controlled devices of the heat pump cycle 10b, similar to the waste heat heating mode of the third embodiment.

[0585] In the waste heat heating mode, the high-temperature side heat transfer medium circuit 60 is closed by the control device 50. In addition, the control device 50 controls the operation of various other controlled devices, similar to the waste heat heating mode in the third embodiment.

[0586] In the low-temperature side heat transfer medium circuit 30b of the waste heat heating mode, the control device 50 closes the fourth heat transfer medium flow rate adjustment valve 36d completely. In addition, the control device 50 controls the operation of various other controlled devices, similar to the waste heat heating mode of the third embodiment.

[0587] In the indoor air conditioning unit 40 operating in waste heat heating mode, the control device 50 controls the operation of various controlled devices, similar to the waste heat heating mode in the third embodiment.

[0588] Therefore, in the waste heat heating mode heat pump cycle 10b, a vapor compression type refrigeration cycle is configured in which the water-refrigerant heat exchanger 121 functions as a condenser and the chiller 20 functions as an evaporator. As a result, the high-temperature side heat transfer medium is heated in the water-refrigerant heat exchanger 121, and the low-temperature side heat transfer medium is cooled in the chiller 20.

[0589] In the high-temperature side heat transfer medium circuit 60 of the waste heat heating mode, the blown air is heated in the heater core 64, similar to the third embodiment.

[0590] In the low-temperature heat transfer medium circuit 30b of the waste heat heating mode, the battery 80 and the high-voltage electrical equipment 81 are cooled, similar to the cooling mode. Furthermore, in the waste heat heating mode, the fourth heat transfer medium flow rate control valve 36d is fully closed, so the blown air is not cooled by the cooler core 39.

[0591] In the waste heat heating mode of the interior air conditioning unit 40, temperature-controlled air is blown out through openings to appropriate locations within the vehicle interior, similar to the third embodiment. This provides heating to the vehicle interior. Furthermore, in the waste heat heating mode, similar to the third embodiment, waste heat from the battery 80, waste heat from the high-voltage equipment 81, and heat from the outside air can be used as heat sources to heat the air in the heater core 64.

[0592] (k) Hot gas start mode In the hot gas start-up mode of the heat pump cycle 10b, the control device 50 closes the cooling flow control valve 16c completely and restricts the bypass flow control valve 16d.

[0593] Therefore, in the hot gas start mode heat pump cycle 10a, the refrigerant circuit is switched to one in which the refrigerant circulates in the same order as in the hot gas start mode of the first embodiment. Accordingly, the usage mode of the ejector 70 in the hot gas start mode is nozzle mode. Other operations are the same as in the first embodiment.

[0594] Therefore, in hot gas startup mode, the suction refrigerant pressure Ps and suction refrigerant temperature Ts can be rapidly increased, similar to the first embodiment.

[0595] (l) Hot gas heating mode In the hot gas heating mode heat pump cycle 10b, the control device 50 restricts the cooling flow control valve 16c and the bypass flow control valve 16d.

[0596] Therefore, in the hot gas heating mode, the heat pump cycle 10b is switched to a refrigerant circuit in which the refrigerant circulates in the same order as in the hot gas heating mode of the first embodiment. Accordingly, the ejector 70 is used in suction mode in the hot gas heating mode. The control device 50 also controls the operation of each component of the heat pump cycle 10b, similar to the hot gas heating mode of the first embodiment.

[0597] In the hot gas heating mode, the high-temperature side heat transfer medium circuit 60 controls the operation of various controlled devices, similar to the waste heat heating mode. Other operations are the same as in the hot gas heating mode of the first embodiment.

[0598] Therefore, in hot gas heating mode, similar to the first embodiment, the heating capacity of the blown air can be rapidly improved to achieve heating inside the vehicle.

[0599] (m) Hot gas waste heat heating mode In the heat pump cycle 10b of the hot gas waste heat heating mode, the control device 50 sets the cooling flow control valve 16c to a throttled state and the bypass flow control valve 16d to a throttled state.

[0600] Therefore, in the heat pump cycle 10b of the hot gas waste heat heating mode, the refrigerant circuit is switched to one in which the refrigerant circulates in the same order as in the hot gas heating mode. Consequently, the ejector 70 is used in suction mode in the hot gas heating mode. In addition, the control device 50 controls the operation of other controlled equipment, similar to the waste heat heating mode.

[0601] Therefore, in the hot gas waste heat heating mode, similar to the first embodiment, the heating capacity of the blown air can be rapidly improved to achieve heating inside the vehicle. Furthermore, the chiller 20 can absorb the heat from the low-temperature heat transfer medium into the refrigerant, which can then be used as a heat source for heating the blown air in the heater core 64.

[0602] (o) Hot gas parallel dehumidification heating mode In the hot gas parallel dehumidification heating mode heat pump cycle 10b, the control device 50 sets the cooling flow control valve 16c to a throttled state and the bypass flow control valve 16d to a throttled state.

[0603] Therefore, in the heat pump cycle 10b of the hot gas parallel dehumidification heating mode, the refrigerant circuit is switched to one in which the refrigerant circulates in the same order as in the hot gas heating mode. Consequently, the ejector 70 is used in suction mode in the hot gas heating mode.

[0604] In the hot gas parallel dehumidifying heating mode, the high-temperature side heat transfer medium circuit 60 controls the operation of various controlled devices, similar to the cooling mode.

[0605] In the low-temperature side heat transfer medium circuit 30b of the hot gas parallel dehumidifying heating mode, the control device 50 controls the operation of various controlled devices, similar to the cooling mode.

[0606] In the indoor air conditioning unit 40 operating in hot gas parallel dehumidification heating mode, the control device 50 controls the operation of various controlled devices, similar to the cooling mode.

[0607] Therefore, in the hot gas parallel dehumidification heating mode of the indoor air conditioning unit 40, the blown air cooled and dehumidified by the cooler core 39 can be reheated by the heater core 64. The temperature-controlled blown air is then blown out through the openings to the appropriate locations in the vehicle interior. This achieves dehumidification heating in the vehicle interior. Furthermore, similar to the first embodiment, the heating capacity of the blown air can be rapidly improved to achieve dehumidification heating in the vehicle interior.

[0608] As described above, the vehicle air conditioning system 1b of this embodiment can provide comfortable air conditioning inside the vehicle and appropriate temperature control for in-vehicle equipment by switching the operating mode.

[0609] Furthermore, the vehicle air conditioning system 1b of this embodiment can achieve the same effects as the first embodiment. That is, in the operating mode performed at extremely low ambient temperatures, the refrigerant pressure boosting action of the ejector 70 rapidly increases the intake refrigerant pressure Ps, thereby achieving highly immediate heating.

[0610] (Fifth embodiment) In this embodiment, a modified example of the vehicle air conditioning system 1b described in the fourth embodiment will be described. As shown in the overall configuration diagram of Figure 46, the vehicle air conditioning system 1b of this embodiment is equipped with an accumulator 22 instead of a receiver 15.

[0611] The accumulator 22 is a low-pressure gas-liquid separation unit that separates the gaseous and liquid phases of the low-pressure refrigerant flowing out from the refrigerant outlet 723 of the ejector 70. The accumulator 22 is a low-pressure liquid storage unit that allows a portion of the separated gaseous refrigerant to flow downstream and stores the liquid phase refrigerant as excess refrigerant in the cycle. The gaseous refrigerant outlet of the accumulator 22 is connected to the refrigerant suction port side of the compressor 11. The other configurations of the vehicle air conditioning system 1b are the same as in the fourth embodiment.

[0612] In the vehicle air conditioning system 1b of this embodiment, the operating mode can be switched, similar to the fourth embodiment. Specifically, (a) cooling mode, (i) waste heat heating mode, (k) hot gas start mode, (l) hot gas heating mode, (m) hot gas waste heat heating mode, and (o) hot gas parallel dehumidification heating mode can be performed.

[0613] Furthermore, in this embodiment, the control device 50 can control the throttle opening of the cooling flow rate control valve 16c in each operating mode so that the degree of subcooling SC of the refrigerant flowing out of the refrigerant passage of the water-refrigerant heat exchanger 121 approaches the target degree of subcooling SCO. The target degree of subcooling SCO is determined based on the discharge refrigerant pressure Pd by referring to a control map stored in the control device 50 in advance.

[0614] The control map determines the target supercooling degree SCO such that the coefficient of performance (i.e., COP) of the cycle is maximized. Other operations are the same as in the fourth embodiment.

[0615] According to the vehicle air conditioning system 1b of this embodiment, comfortable air conditioning in the vehicle cabin and appropriate temperature adjustment of in-vehicle equipment can be achieved by switching the operating mode. Furthermore, similar to the fourth embodiment, when operating in an operating mode that is performed at extremely low outside temperatures, the refrigerant pressure boosting action of the ejector 70 rapidly increases the intake refrigerant pressure Ps, thereby achieving highly effective immediate heating.

[0616] (Sixth Embodiment) In this embodiment, a modified version of the vehicle air conditioning system 1b described in the fourth embodiment will be described. As shown in the overall configuration diagram of Figure 47, the vehicle air conditioning system 1b of this embodiment has a modified arrangement of the accumulator 22 compared to the seventh embodiment.

[0617] Specifically, in this embodiment, the inlet side of the accumulator 22 is connected to the outlet of the refrigerant passage of the chiller 20. The refrigerant suction port 721 of the ejector 70 is connected to the gas phase refrigerant outlet of the accumulator 22. The other configurations are the same as in the fourth embodiment.

[0618] In the vehicle air conditioning system 1b of this embodiment, the operating mode can be switched, similar to the fifth embodiment. Specifically, (a) cooling mode, (i) waste heat heating mode, (k) hot gas start mode, (l) hot gas heating mode, (m) hot gas waste heat heating mode, and (o) hot gas parallel dehumidification heating mode can be performed.

[0619] In the vehicle air conditioning system 1b of this embodiment, when the ejector 70 is in suction mode during hot gas operation, gaseous refrigerant is drawn in from the refrigerant suction port 721 of the ejector 70. Even with this configuration, the pressurizing action of the ejector 70 rapidly increases the suction refrigerant pressure Ps, enabling highly effective and immediate heating.

[0620] (Seventh Embodiment) In this embodiment, an example is described in which the heat pump cycle device according to the present invention is applied to a vehicle air conditioning system 1c shown in the overall configuration diagram of Figure 48. The vehicle air conditioning system 1c is an air conditioning system with an on-board equipment temperature control function, similar to that of the first embodiment. The vehicle air conditioning system 1c includes a heat pump cycle 10c, a low-temperature side heat transfer medium circuit 30b, an indoor air conditioning unit 40, a control device 50, a high-temperature side heat transfer medium circuit 60, and the like.

[0621] In the heat pump cycle 10c, the arrangement of the ejector 70 is changed compared to the heat pump cycle 10b described in the fourth embodiment.

[0622] Specifically, in the heat pump cycle 10c, the refrigerant suction port 721 side of the ejector 70 is connected to the outlet of the cooling flow control valve 16c. Furthermore, the inlet side of the refrigerant passage of the chiller 20 is connected to the refrigerant outlet 723 of the ejector 70. The suction port side of the compressor 11 is connected to the outlet of the refrigerant passage of the chiller 20. The other configurations are the same as in the fourth embodiment.

[0623] In the vehicle air conditioning system 1c of this embodiment, the operating mode can be switched, similar to the fourth embodiment. Specifically, (a) cooling mode, (i) waste heat heating mode, (k) hot gas start mode, and (l) hot gas heating mode can be performed.

[0624] According to the vehicle air conditioning system 1c of this embodiment, comfortable air conditioning in the vehicle cabin and appropriate temperature adjustment of in-vehicle equipment can be achieved by switching the operating mode. Furthermore, similar to the fourth embodiment, when operating in an operating mode that is performed at extremely low outside temperatures, the refrigerant pressure boosting action of the ejector 70 rapidly increases the intake refrigerant pressure Ps, thereby achieving highly effective immediate heating.

[0625] Furthermore, in the vehicle air conditioning system 1c of this embodiment, (m) hot gas waste heat heating mode and (o) hot gas parallel dehumidification heating mode may be implemented. In the vehicle air conditioning system 1c, the inlet side of the refrigerant passage of the chiller 20 is connected to the refrigerant outlet 723 of the ejector 70. For this reason, in the (m) hot gas waste heat heating mode and (o) hot gas parallel dehumidification heating mode of this embodiment, the refrigerant evaporation temperature in the chiller 20 increases compared to the fourth embodiment.

[0626] (Eighth embodiment) In this embodiment, the vehicle air conditioning system 1d shown in the overall configuration diagram of Figure 49 will be described. The vehicle air conditioning system 1d is an air conditioning system with an on-board equipment temperature control function, similar to that of the first embodiment. The vehicle air conditioning system 1d includes a heat pump cycle 10d, a low-temperature side heat transfer medium circuit 30b, an indoor air conditioning unit 40, a control device 50, a high-temperature side heat transfer medium circuit 60, and the like.

[0627] The heat pump cycle 10d differs from the heat pump cycle 10b described in the fifth embodiment in that the arrangement of the ejector 70 is changed.

[0628] Specifically, in the heat pump cycle 10d, the nozzle inlet 711 side of the nozzle portion 71 of the ejector 70 is connected to the outlet of the cooling flow control valve 16c. Furthermore, the refrigerant suction port 721 side of the ejector 70 is connected to the outlet of the bypass flow control valve 16d. The other configurations are the same as in the fourth embodiment.

[0629] In the vehicle air conditioning system 1d of this embodiment, the operating mode can be switched, similar to the fourth embodiment. Specifically, it can be switched between (a) cooling mode, (i) waste heat heating mode, and (l) hot gas heating mode.

[0630] In this embodiment, the vehicle air conditioning system 1d allows the refrigerant with a relatively low enthalpy that has flowed out from the cooling flow control valve 16c to flow into the nozzle portion 71 of the ejector 70. As a result, the adiabatic enthalpy drop at the nozzle portion 71 is reduced compared to the (l) hot gas heating mode of the fourth embodiment.

[0631] Therefore, although the refrigerant pressure boosting capacity of the ejector 70 is lower than that of vehicle air conditioning systems 1a, etc., it is possible to raise the intake refrigerant pressure Ps more quickly than vehicle air conditioning systems without an ejector, thereby achieving highly effective and immediate heating.

[0632] (Ninth Embodiment) In this embodiment, the vehicle air conditioning system 1e shown in the overall configuration diagram of Figure 50 will be described. The vehicle air conditioning system 1e is an air conditioning system with an on-board equipment temperature control function, similar to that of the first embodiment. The vehicle air conditioning system 1e includes a heat pump cycle 10e, a low-temperature side heat transfer medium circuit 30b, an indoor air conditioning unit 40, a control device 50, a high-temperature side heat transfer medium circuit 60, and the like.

[0633] The heat pump cycle 10e is modified from the heat pump cycle 10b described in the fourth embodiment by adding a heating flow control valve 16a and an outdoor heat exchanger 18, as well as changing the arrangement of the ejector 70.

[0634] Specifically, in the heat pump cycle 10e, the inlet side of the 10th three-way joint 13j is connected to the liquid phase refrigerant outlet of the receiver 15. The 10th three-way joint 13j is the downstream branching point.

[0635] One outlet of the 10th three-way joint 13j is connected to the inlet side of the heating flow control valve 16a. The outlet of the heating flow control valve 16a is connected to the refrigerant inlet side of the outdoor heat exchanger 18. The refrigerant outlet of the outdoor heat exchanger 18 is connected to the refrigerant suction port 721 side of the ejector 70. The refrigerant outlet 723 of the ejector 70 is connected to one inlet side of the 11th three-way joint 13k.

[0636] Furthermore, the inlet side of the cooling flow control valve 16c is connected to the other outlet of the 10th three-way joint 13j. Also, the inlet side of the other end of the 11th three-way joint 13k is connected to the outlet of the refrigerant passage of the chiller 20. The suction side of the compressor 11 is connected to the outlet of the 11th three-way joint 13k.

[0637] Therefore, in this embodiment, the heating flow control valve 16a is the first heating section side flow control section, and the cooling flow control valve 16c is the second heating section side flow control section. Also, the 11th three-way joint 13k is a junction section. The other configurations are the same as in the fourth embodiment.

[0638] In the vehicle air conditioning system 1e of this embodiment, the operating mode can be switched in the same way as in the first embodiment. Specifically, by closing the heating flow control valve 16a completely, throttling the cooling flow control valve 16c, and closing the bypass-side flow control valve 16d completely, the same (a) cooling mode and (i) waste heat heating mode as in the fourth embodiment can be performed.

[0639] Furthermore, by fully closing the heating flow control valve 16a, fully closing the cooling flow control valve 16c, and throttling the bypass-side flow control valve 16d, the same (k) hot gas startup mode as in the fourth embodiment can be executed. In addition, as an operating mode in which the ejector is used in suction mode, the (n) hot gas outside air heat absorption heating mode can be executed. The (n) hot gas outside air heat absorption heating mode will be described below.

[0640] (n) Hot gas outside air heat absorption heating mode In the heat pump cycle 10e of the hot gas outside air intake heating mode, the control device 50 sets the heating flow control valve 16a to a throttled state, the cooling flow control valve 16c to a throttled state, and the bypass side flow control valve 16d to a throttled state.

[0641] Therefore, in the hot gas outside air heat absorption heating mode heat pump cycle 10e, as shown by the black arrows in Figure 50, the refrigerant discharged from the compressor 11 is switched to a refrigerant circuit in which it flows in the following order: water refrigerant heat exchanger 121, receiver 15, heating flow control valve 16a, outdoor heat exchanger 18, and refrigerant suction port 721 of the ejector 70. At the same time, the refrigerant discharged from the compressor 11 is switched to a refrigerant circuit in which it flows in the following order: water refrigerant heat exchanger 121, receiver 15, cooling flow control valve 16c, refrigerant passage of chiller 20, and refrigerant suction port 721 of the ejector 70. At the same time, the refrigerant discharged from the compressor 11 is switched to a refrigerant circuit in which it flows in the following order: bypass-side flow control valve 16d located in the bypass passage 21c, and nozzle section 71 of the ejector 70, and the refrigerant that flows out from the refrigerant outlet 723 of the ejector 70 is drawn into the compressor 11. Therefore, the mode of use of the ejector 70 in the hot gas outside air intake heating mode is the suction mode.

[0642] Furthermore, the control device 50 controls the throttle opening of the heating flow control valve 16a so that the outdoor unit side refrigerant temperature T2 detected by the outdoor unit temperature sensor 52e is lower than the outside temperature Tam. Also, the control device 50 controls the operation of the other components of the heat pump cycle 10e, similar to the hot gas outside air intake heating mode of the first embodiment.

[0643] In the low-temperature side heat transfer medium circuit 30 of the hot gas outside air heat intake heating mode, the control device 50 stops the low-temperature side heat transfer medium pump 31.

[0644] In the high-temperature side heat transfer medium circuit 60 of the hot gas outside air heat absorption heating mode, the control device 50 controls the operation of various controlled devices, similar to the waste heat heating mode of the fourth embodiment. Other operations are the same as in the hot gas heating mode of the first embodiment.

[0645] Therefore, in the heat pump cycle 10e of the hot gas outside air intake heating mode, the state of the refrigerant changes as shown in the Mollier diagram in Figure 51.

[0646] In other words, the flow of refrigerant discharged from the compressor 11 (point a51 in Figure 51) is branched at the first three-way joint 13a. One of the refrigerants branched at the first three-way joint 13a flows into the refrigerant passage of the water refrigerant heat exchanger 121. The refrigerant that flows into the refrigerant passage of the water refrigerant heat exchanger 121 releases heat into the high-temperature side heat transfer medium flowing through the heat transfer medium passage and condenses. As a result, the high-temperature side heat transfer medium is heated.

[0647] The refrigerant flowing out of the water-refrigerant heat exchanger 121 flows into the receiver 15 where it is separated into gas and liquid phases (from point a51 to point g51 in Figure 51). The flow of liquid-phase refrigerant flowing out of the receiver 15 is branched at the 10th three-way joint 13j.

[0648] One of the refrigerants, branched off at the 10th three-way joint 13j, flows into the heating flow control valve 16a and is depressurized (from point g51 to point d51 in Figure 51). The refrigerant, depressurized at the heating flow control valve 16a, flows into the outdoor heat exchanger 18. The refrigerant that flows into the outdoor heat exchanger 18 absorbs heat from the outside air and evaporates (from point d51 to region P51 in Figure 51).

[0649] Furthermore, the other refrigerant branched off at the first three-way joint 13a flows into the nozzle section 71 of the ejector 70 via the bypass flow control valve 16d, similar to the hot gas heating mode, and is depressurized (from point a51 in Figure 51 to region P51).

[0650] Inside the ejector 70, similar to the hot gas heating mode, the injected refrigerant sprayed from the nozzle section 71 and the suctioned refrigerant drawn in from the refrigerant suction port 721 merge in the mixing and pressurizing section 722. The mixed refrigerant is then pressurized by the shock wave generated in the mixing and pressurizing section 722. The refrigerant that flows out from the refrigerant outlet 723 of the ejector 70 flows into one of the inlets of the 11th three-way joint 13k (from region P51 to point s51 in Figure 51).

[0651] Furthermore, one of the refrigerants branched off at the 10th three-way joint 13j flows into the cooling flow control valve 16c and is depressurized (from point g51 to point k51 in Figure 51). The refrigerant depressurized by the cooling flow control valve 16c flows into the refrigerant passage of the chiller 20.

[0652] In the hot gas outside air intake heating mode, the low-temperature side heat transfer fluid pump 31 is stopped, so the refrigerant flowing into the chiller 20 flows into the other inlet of the 11th three-way joint 13k without exchanging heat with the low-temperature side heat transfer fluid (from point k51 to point s51 in Figure 51).

[0653] The refrigerants that merged at the 11th three-way joint 13k are drawn into the compressor 11 and compressed again (from point s51 to point a51 in Figure 51).

[0654] In the hot gas outside air intake heating mode, the high-temperature side heat transfer medium circuit 60 is heated by the heater core 64, similar to the waste heat heating mode.

[0655] In the hot gas outside air intake heating mode, the high-temperature side heat transfer medium circuit 60, similar to the waste heat heating mode, is blown through openings to appropriate locations within the vehicle interior. This achieves heating of the vehicle interior.

[0656] As described above, the vehicle air conditioning system 1e of this embodiment can provide comfortable air conditioning inside the vehicle and appropriate temperature control for in-vehicle equipment by switching the operating mode.

[0657] Furthermore, the vehicle air conditioning system 1e of this embodiment can achieve the same effects as the first embodiment. That is, in the operating mode performed at extremely low ambient temperatures, the refrigerant pressure boosting action of the ejector 70 rapidly increases the intake refrigerant pressure Ps, thereby achieving highly immediate heating.

[0658] Furthermore, in the hot gas outside air heat absorption heating mode of this embodiment, the pressure-boosting action of the ejector 70 makes it possible to lower the refrigerant pressure in the outdoor heat exchanger 18 below the intake refrigerant pressure Ts. This lowers the refrigerant evaporation temperature in the outdoor heat exchanger 18 below the ambient temperature Tam. Therefore, the heat contained in the outside air is absorbed by the refrigerant in the outdoor heat exchanger 18 and can be used as a heat source to heat the blown air in the indoor condenser 12.

[0659] (Other embodiments) The present invention is not limited to the embodiments described above, and can be modified in various ways as follows without departing from the spirit of the invention.

[0660] (1) In the above-described embodiment, an example was given in which the heat pump cycle device according to the present invention is applied to a vehicle air conditioning system. However, the application of the heat pump cycle device is not limited to vehicle air conditioning systems. For example, it may be applied to a hot water supply system that heats water for domestic use as the object to be heated. For example, it may be applied to an air conditioning system with a server cooling function that provides air conditioning to a room while appropriately adjusting the temperature of a computer server.

[0661] Furthermore, when the heat pump cycle device according to the present invention is applied to a vehicle air conditioning system, the temperature of on-board equipment such as a motor generator, inverter, sensor processing unit, transaxle, and ADAS control device may be adjusted.

[0662] A motor-generator is an electric motor that functions as both a motor that outputs driving force for propulsion and a generator. An inverter is an electrical circuit device that supplies power to the motor-generator and other components. A sensor processing unit is a control device that integrates the interface and communication functions of environmental sensors for autonomous driving and energy-saving operation. A transaxle is a power transmission mechanism that integrates the transmission, differential gear, and other components. An ADAS control device is a control device for advanced driver-assistance systems.

[0663] (2) The configuration of the heat pump cycle device according to the present invention is not limited to the configuration disclosed in the above-described embodiments.

[0664] For example, multiple components may be integrated to the extent possible. Specifically, a four-way joint may be adopted by integrating the seventh three-way joint 13g and the eighth three-way joint 13h described in the first embodiment. Alternatively, a three-way flow control valve may be adopted by integrating any two of the first heat transfer medium flow control valves 36a to the fourth heat transfer medium flow control valves 36d.

[0665] Furthermore, in the embodiments described above, heat pump cycles 10 to 10e employing an outdoor heat exchanger 18, an indoor evaporator 19, and a chiller 20 as the suction-side heat exchange section were described, but the suction-side heat exchange section is not limited to this. For example, a heat exchange section for ventilation heat recovery may be employed, which exchanges heat between a low-pressure refrigerant and the indoor air flowing out from the air-conditioned space, thereby allowing the heat contained in the indoor air to be absorbed by the low-pressure refrigerant.

[0666] Furthermore, the group of control sensors connected to the input side of the control device 50 is not limited to the detection unit disclosed in the above-described embodiment. Various detection units may be added as needed.

[0667] Furthermore, although the above-described embodiment explained an example in which R1234yf was used as the refrigerant for the heat pump cycles 10 to 10e, the invention is not limited to this. For example, R134a, R600a, R410A, R404A, R32, R407C, R290, etc. may be used. A mixture of several of these refrigerants may also be used. Moreover, R744 may be used as the refrigerant to configure a supercritical refrigeration cycle in which the high-pressure side refrigerant pressure is equal to or greater than the critical pressure of the refrigerant.

[0668] It is desirable that the refrigerant used has a saturation pressure at the same temperature that is equal to or greater than the saturation pressure of R1234yf.

[0669] The reason for this is that even if a high pressure boost ratio (Pout / Psuc) is obtained in ejectors 70 and 70a, if the pressure Psuc of the suctioned refrigerant is low, the pressure (absolute value) of the refrigerant flowing out from the refrigerant outlet 723 of ejectors 70 and 70a will also be low. Therefore, in order to quickly achieve sufficient heating capacity in the heat pump cycles 10 to 10e, it is desirable to use refrigerants such as R1234yf, R290, or R744.

[0670] Furthermore, although the above-described embodiment described an example in which an aqueous ethylene glycol solution was used as the low-temperature and high-temperature heat transfer fluids, the invention is not limited to this. As the high-temperature and low-temperature heat transfer fluids, for example, a solution containing dimethylpolysiloxane or nanofluids, antifreeze, an aqueous liquid refrigerant containing alcohol, or a liquid medium containing oil may be used.

[0671] (3) The control modes of the heat pump cycle device according to the present invention are not limited to the control modes disclosed in the embodiments described above.

[0672] In the embodiments described above, vehicle air conditioning systems 1 to 1e capable of performing various operating modes have been described, but it is not necessary for the system to be able to perform all of the above operating modes. The air conditioning system according to the present invention can achieve the effects described in the embodiments above as long as it is capable of performing at least one operating mode in which the ejector 70 is used in (γ) suction mode.

[0673] In other words, when operating in an operating mode that is performed at extremely low ambient temperatures, the refrigerant pressure boosting action of the ejector 70 rapidly increases the intake refrigerant pressure Ps, thereby achieving highly effective and immediate heating.

[0674] Of course, other operating modes may also be possible. For example, in the (n) hot gas outside air heat absorption heating mode of the ninth embodiment, the low-temperature side heat transfer medium pump 31 may be activated to enable a hot gas outside air heat absorption waste heat heating mode in which the chiller 20 absorbs the heat contained in the low-temperature side heat transfer medium into the refrigerant. This makes it possible to lower the refrigerant pressure in the outdoor heat exchanger 18 to a level lower than the refrigerant pressure in the chiller 20.

[0675] Furthermore, in the above-described embodiment, an example was given in which the throttle opening of the bypass-side flow control valve 16d was controlled so that the injected refrigerant was in an under-expansion state, as described in (l) hot gas heating mode, but the embodiment is not limited to this. For example, the refrigerant discharge capacity of the compressor 11 may be controlled so that the injected refrigerant is in an under-expansion state. In addition, the throttle opening of the bypass-side flow control valve 16d may be controlled so that the discharge refrigerant pressure Pd approaches the target high pressure PDO.

[0676] Furthermore, in the embodiments described above, an example was described in which the throttle opening of the bypass-side flow control valve 16d was controlled so that the injected refrigerant becomes over-expanded, as described in (k) the hot gas start mode, but the invention is not limited to this. For example, the refrigerant discharge capacity of the compressor 11 may be controlled so that the injected refrigerant becomes under-expanded at low rotational speeds within a range where liquid compression problems do not occur.

[0677] Furthermore, in the above-described embodiment, an example was explained in which the refrigerant discharge capacity of the compressor 11 was controlled so that the refrigerant evaporation temperature in the suction-side heat exchange section was higher than the reference lower limit temperature KTem during hot gas operation mode, but the system is not limited to this. The throttle openings of various flow control valves may also be controlled so that the refrigerant evaporation temperature in the suction-side heat exchange section is higher than the reference lower limit temperature KTem.

[0678] Furthermore, in the above-described embodiment, as explained in (k) hot gas start mode, the throttle opening of the cooling flow control valve 16c, which is the heating unit side flow control unit, was controlled so that the superheat SHS of the intake refrigerant approached the reference superheat KSH, but the embodiment is not limited to this.

[0679] For example, the throttle opening of the bypass-side flow control valve 16d may be controlled so that the superheat level SHS of the intake refrigerant approaches the reference superheat level KSH. Furthermore, the throttle opening of the heating-side flow control unit may be controlled so that the injected refrigerant enters an under-expansion state.

[0680] Furthermore, although the above-described embodiment described an example in which the hot gas start mode was continued until the intake refrigerant temperature Ts became equal to or greater than the reference hot gas temperature KHGTs, the embodiment is not limited to this.

[0681] For example, the hot gas start mode may be maintained from the time the compressor 11 is started until a predetermined standard start time Twu has elapsed. After the hot gas start mode ends, the system can be switched to a hot gas operation mode in which the ejectors 70 and 70a are used in suction mode.

[0682] The reference startup time Twu can be determined by referring to a control map pre-stored in the control device 50, based on the ambient temperature Tam. Specifically, the reference startup time Twu should be determined so that it increases as the ambient temperature Tam decreases.

[0683] Furthermore, although the above embodiment describes an example in which the compressor 11 is actively switched to hot gas start mode when it is started, the invention is not limited to this.

[0684] For example, the hot gas heating mode may be executed when the compressor 11 is started. As mentioned above, when the compressor 11 is started, the intake refrigerant may be in a gas-liquid two-phase state. Therefore, similar to the hot gas heating mode, if the throttle opening of the cooling flow control valve 16c is controlled so that the superheat level SHS approaches the reference superheat level KSH, the cooling flow control valve 16c will approach a fully closed state.

[0685] Therefore, if the opening of the cooling flow control valve 16c is less than or equal to a predetermined reference starting opening, the control device 50 can control the throttle opening of the bypass-side flow control valve 16d so that the injected refrigerant enters an over-expanded state. This makes it possible to achieve operation similar to that of the hot gas starting mode.

[0686] (4) The means disclosed in each of the above embodiments may be combined as appropriate to the extent that they are feasible. For example, the ejector 70a described in the second embodiment may be applied to the heat pump cycles 10a to 10e described in the third to ninth embodiments.

[0687] For example, the indoor condenser 12 described in the first embodiment may be used as a heating unit and applied to the heat pump cycles 10a to 10e described in the third to ninth embodiments. Of course, the components of the water refrigerant heat exchanger 121 and the high-temperature side heat transfer medium circuit 60 described in the second embodiment may also be used as heating units and applied to the heat pump cycle 10 described in the first embodiment.

[0688] The features of the heat pump cycle apparatus disclosed herein are as follows: (Item 1) A compressor (11) that compresses and discharges the refrigerant, An upstream branching section (13a) that branches the flow of the refrigerant discharged from the compressor, A heating section (12, 121, 60) that heats an object to be heated using one of the refrigerants branched at the upstream branch section as a heat source, A heating section side flow rate adjustment section (16a, 16b, 16c) adjusts the flow rate of the refrigerant flowing out from the heating section, A bypass passage (21c) is provided to allow the other refrigerant, which was branched at the upstream branching section, to flow around the heating section. A bypass-side flow rate adjustment unit (16d, 73) adjusts the flow rate of the refrigerant flowing through the bypass passage, The ejector (70, 70a) has a nozzle section (71) that accelerates and injects the refrigerant that has flowed out from the bypass passage, a refrigerant suction port (721) that draws in the gas-liquid two-phase refrigerant that has flowed out from the heating section side flow rate adjustment section, and a body section (72) formed therein that discharges the refrigerant that has flowed inside toward the compressor's suction port side, The nozzle portion is formed with a throat portion (713) that minimizes the passage cross-sectional area, and a flared portion (714) that increases the passage cross-sectional area as it moves from the throat portion towards the nozzle (715). The ejector is a heat pump cycle device that raises the pressure of the refrigerant at the refrigerant outlet to a level higher than the pressure of the refrigerant at the refrigerant suction port by the action of a shock wave. (Item 2) The heat pump cycle device according to item 1, wherein the bypass-side flow rate adjustment unit adjusts the flow rate of the refrigerant flowing through the bypass passage by changing the cross-sectional area of ​​the refrigerant passage formed in the nozzle. (Item 3) The heat pump cycle device according to item 1 or 2, wherein the body portion has a mixing section (722a) formed therein, which brings the mixed refrigerant, obtained by mixing the injected refrigerant sprayed from the nozzle portion and the suctioned refrigerant sucked in from the refrigerant suction port, closer to an equilibrium state. (Item 4) The aforementioned mixing section is formed as a cylindrical space in which the cross-sectional area of ​​the refrigerant passage is constant. The mixing section distance L, which is the length of the mixing section in the direction of refrigerant flow, is the heat pump cycle device described in item 3 that satisfies equations (1) and (2).

[0689]

number

[0690]

number

[0691] However, u0 is the velocity of the refrigerant at the inlet of the mixing section, and ρ l D is the density of the liquid phase refrigerant at the inlet of the mixing section. l μ is the droplet diameter of the liquid phase refrigerant at the inlet of the mixing section. g This is the viscosity of the gaseous refrigerant at the inlet of the mixing section. (Item 5) The ejector has a mode of operation in which the refrigerant is introduced into the nozzle and the refrigerant is drawn in from the refrigerant suction port. The heat pump cycle apparatus according to any one of items 1 to 4, wherein when the ejector is used in the suction mode, the refrigerant discharge capacity of the compressor and at least one of the throttle opening of the bypass-side flow rate adjustment unit are adjusted so that the refrigerant injected from the nozzle is in an under-expanded state. (Item 6) The ejector has a nozzle mode in which the refrigerant is introduced into the nozzle section and the refrigerant flow path communicating with the refrigerant suction port is closed. The heat pump cycle apparatus according to item 5, wherein when the ejector is used in the nozzle mode, at least one of the refrigerant discharge capacity of the compressor and the throttle opening of the bypass-side flow rate adjustment unit are adjusted so that the refrigerant injected from the nozzle becomes over-expanded. (Item 7) The ejector is a heat pump cycle device as described in item 6, used in the nozzle mode when the compressor is started. (Item 8) The ejector is a heat pump cycle device according to any one of items 5 to 7 used in the suction mode when the suction refrigerant temperature (Ts), which is the temperature of the suction refrigerant drawn into the compressor, is equal to or greater than a predetermined reference hot gas temperature (KHGTs). (Item 9) The ejector is used in the suction mode after a predetermined reference start time (Twu) has elapsed from the start of the compressor, in the heat pump cycle device described in any one of items 5 to 7. (Item 10) In the suction mode, the heat pump cycle apparatus according to any one of items 5 to 9, wherein at least one of the throttle opening of the heating section side flow rate adjustment unit and the throttle opening of the bypass side flow rate adjustment unit is adjusted so that the refrigerant discharged from the ejector becomes a gaseous refrigerant with a degree of superheating. (Item 11) The system includes suction-side heat exchange sections (18, 19, 20) for exchanging heat between the refrigerant and the object to be heat exchanged, The heat pump cycle device according to any one of items 5 to 10, wherein, in the suction mode, the refrigerant in the suction-side heat exchange unit is suctioned from the refrigerant suction port. (Item 12) The system includes suction-side heat exchange sections (18, 19, 20) that exchange heat between the refrigerant, which has been depressurized in the heating section-side flow rate adjustment section, and the object to be heat exchanged. A heat pump cycle device according to any one of items 5 to 10, wherein, in the suction mode, the refrigerant in the suction-side heat exchange section heats the object to be heated using the heat absorbed from the object to be heat exchanged as a heat source. (Item 13) A heat pump cycle device according to any one of items 1 to 12, wherein the refrigerant used has a saturation pressure at the same temperature that is equal to or greater than the saturation pressure of R1234yf. (Item 14) A compressor (11) that compresses and discharges the refrigerant, An upstream branching section (13a) that branches the flow of the refrigerant discharged from the compressor, A heating section (12, 121, 60) that heats an object to be heated using one of the refrigerants branched at the upstream branch section as a heat source, A heating section side flow rate adjustment section (16a, 16b, 16c) adjusts the flow rate of the refrigerant flowing out from the heating section, A bypass passage (21c) is provided to allow the other refrigerant, which was branched at the upstream branching section, to flow around the heating section. A bypass-side flow rate adjustment unit (16d, 73) adjusts the flow rate of the refrigerant flowing through the bypass passage, The ejector (70, 70a) comprises a nozzle section (71) that accelerates and injects the gas-liquid two-phase refrigerant flowing out from the heating section side flow rate adjustment section, and a body section (72) formed with a refrigerant suction port (721) that sucks in the refrigerant flowing out from the bypass passage, and a refrigerant outlet (723) that causes the refrigerant that has flowed into the interior to flow out to the compressor suction port side, The nozzle portion is formed with a throat portion (713) that minimizes the passage cross-sectional area, and a flared portion (714) that increases the passage cross-sectional area as it moves from the throat portion towards the nozzle (715). The ejector is a heat pump cycle device that raises the pressure of the refrigerant at the refrigerant outlet to a level higher than the pressure of the refrigerant at the refrigerant suction port by the action of a shock wave. (Item 15) A compressor (11) that compresses and discharges the refrigerant, An upstream branching section (13a) that branches the flow of the refrigerant discharged from the compressor, A heating section (12, 121, 60) that heats an object to be heated using one of the refrigerants branched at the upstream branch section as a heat source, A downstream branching section (13j) that branches the flow of the refrigerant that has flowed out from the heating section, A first heating section side flow rate adjustment section (16a) adjusts the flow rate of one of the refrigerants flowing out from the downstream branch section, An outdoor heat exchange unit (18) that exchanges heat between the refrigerant flowing out from the heating flow rate adjustment unit and the outside air, A second heating section side flow rate adjustment section (16c) adjusts the flow rate of the other refrigerant flowing out from the downstream branch section, A bypass passage (21c) is provided to allow the other refrigerant, which was branched at the upstream branching section, to flow around the heating section. A bypass-side flow rate adjustment unit (16d, 73) adjusts the flow rate of the refrigerant flowing through the bypass passage, An ejector (70, 70a) having a nozzle section (71) for accelerating and injecting the refrigerant that has flowed out from the bypass passage, and a body section (72) formed with a refrigerant suction port (721) for drawing in the refrigerant that has flowed out from the outdoor heat exchange section, and a refrigerant outlet (723) for releasing the refrigerant that has flowed into the interior, The system includes a confluence section (13k) that combines the flow of the refrigerant discharged from the second heating section side flow rate adjustment section and the flow of the refrigerant discharged from the refrigerant outlet, and discharges them toward the suction port side of the compressor. The nozzle portion is formed with a throat portion (713) that minimizes the passage cross-sectional area, and a flared portion (714) that increases the passage cross-sectional area as it moves from the throat portion towards the nozzle (715). The ejector is a heat pump cycle device that raises the pressure of the refrigerant at the refrigerant outlet to a level higher than the pressure of the refrigerant at the refrigerant suction port by the action of a shock wave. [Explanation of symbols]

[0692] 11 Compressor 13a First three-way joint (upstream branch section) 12, 121 Indoor condenser, water refrigerant heat exchanger (heating section) 16a Heating flow control valve (heating section side flow control section) 16b, 16c Cooling flow control valve, Cooling flow control valve (heating section side flow control section) 16d Bypass side flow control valve (bypass side flow control unit) 21c Bypass Passage 60 High temperature side heat medium circuit (heating section) 70, 70a Ejector 71, 72 Nozzle section, Body section 721, 723 Refrigerant suction port, refrigerant outlet

Claims

1. A compressor (11) that compresses and discharges the refrigerant, An upstream branching section (13a) that branches the flow of the refrigerant discharged from the compressor, A heating unit (12, 121, 60) that heats an object to be heated using one of the refrigerants branched at the upstream branch as a heat source, A heating section side flow rate adjustment section (16a, 16b, 16c) adjusts the flow rate of the refrigerant flowing out from the heating section, A bypass passage (21c) is provided to allow the other refrigerant, which was branched off at the upstream branching section, to flow around the heating section. A bypass-side flow rate adjustment unit (16d, 73) adjusts the flow rate of the refrigerant flowing through the bypass passage, The ejector (70, 70a) has a nozzle section (71) that accelerates and injects the refrigerant that has flowed out from the bypass passage, a refrigerant suction port (721) that sucks in the gas-liquid two-phase refrigerant that has flowed out from the heating section side flow rate adjustment section, and a body section (72) formed with a refrigerant outlet (723) that causes the refrigerant that has flowed into the interior to flow out towards the compressor's suction port side, The nozzle portion is formed with a throat portion (713) that minimizes the passage cross-sectional area, and a flared portion (714) that increases the passage cross-sectional area as it moves from the throat portion towards the nozzle (715). The ejector is a heat pump cycle device that raises the pressure of the refrigerant at the refrigerant outlet to a level higher than the pressure of the refrigerant at the refrigerant suction port by the action of a shock wave.

2. The heat pump cycle device according to claim 1, wherein the bypass-side flow rate adjustment unit adjusts the flow rate of the refrigerant flowing through the bypass passage by changing the cross-sectional area of ​​the refrigerant passage formed in the nozzle.

3. The heat pump cycle device according to claim 1, wherein the body portion has a mixing section (722a) formed therein, which brings the mixed refrigerant, obtained by mixing the injected refrigerant sprayed from the nozzle portion and the suctioned refrigerant sucked in from the refrigerant suction port, closer to an equilibrium state.

4. The aforementioned mixing section is formed as a cylindrical space in which the cross-sectional area of ​​the refrigerant passage is constant. The heat pump cycle apparatus according to claim 3, wherein the mixing section distance L, which is the length of the mixing section in the direction of refrigerant flow, satisfies equations (1) and (2). [Math 1] [Math 2] However, u 0 ρ is the velocity of the refrigerant at the inlet of the mixing section. l D is the density of the liquid phase refrigerant at the inlet of the mixing section. l μ is the droplet diameter of the liquid phase refrigerant at the inlet of the mixing section. g This is the viscosity of the gaseous refrigerant at the inlet of the mixing section.

5. The ejector has a mode of operation in which the refrigerant is introduced into the nozzle and the refrigerant is drawn in from the refrigerant suction port. The heat pump cycle apparatus according to claim 1, wherein when the ejector is used in the suction mode, at least one of the refrigerant discharge capacity of the compressor and the opening degree of the bypass side flow rate adjustment unit are adjusted so that the refrigerant injected from the nozzle is in an under-expanded state.

6. The ejector has a nozzle mode in which the refrigerant is introduced into the nozzle section and the refrigerant flow path communicating with the refrigerant suction port is closed. The heat pump cycle apparatus according to claim 5, wherein when the ejector is used in the nozzle mode, at least one of the refrigerant discharge capacity of the compressor and the opening degree of the bypass side flow rate adjustment unit are adjusted so that the refrigerant injected from the nozzle becomes over-expanded.

7. The heat pump cycle apparatus according to claim 6, wherein the ejector is used in the nozzle mode when the compressor is started.

8. The heat pump cycle apparatus according to claim 5, wherein the ejector is used in the suction mode when the suction refrigerant temperature (Ts), which is the temperature of the suction refrigerant drawn into the compressor, is equal to or greater than a predetermined reference hot gas temperature (KHGTs).

9. The heat pump cycle apparatus according to claim 5, wherein the ejector is used in the suction mode after a predetermined reference start time (Twu) has elapsed from the start of the compressor.

10. The heat pump cycle apparatus according to claim 5, wherein in the suction mode, at least one of the throttle opening of the heating section side flow rate adjustment section and the throttle opening of the bypass side flow rate adjustment section is adjusted so that the refrigerant discharged from the ejector becomes a gaseous refrigerant having a degree of superheating.

11. The system includes suction-side heat exchange sections (18, 19, 20) for exchanging heat between the refrigerant and the object to be heat exchanged, The heat pump cycle apparatus according to claim 5, wherein, during the suction mode, the refrigerant in the suction-side heat exchange section is suctioned from the refrigerant suction port.

12. The system includes a suction-side heat exchange section (18, 19, 20) which exchanges heat between the refrigerant, whose pressure has been reduced in the heating section-side flow rate adjustment section, and the object to be heat exchanged. The heat pump cycle apparatus according to claim 5, wherein, in the suction mode, the refrigerant in the suction-side heat exchange section heats the object to be heated using the heat absorbed from the object to be heat exchanged as a heat source.

13. The heat pump cycle device according to any one of claims 1 to 12, wherein the refrigerant used has a saturation pressure at the same temperature that is equal to or greater than the saturation pressure of R1234yf.

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