Refrigeration cycle equipment

Abstract

When the cooling requirement for one evaporator increases, the cooling capacity of that evaporator is effectively increased. [Solution] The system includes a heat sink 12 for releasing heat from the refrigerant discharged from the compressor 11, a first pressure reducing unit 14b for reducing the pressure of the refrigerant released by the heat sink, first evaporators 18 and 25 for evaporating the refrigerant and cooling the heat exchange fluid by allowing the refrigerant reduced by the first pressure reducing unit to absorb heat from the heat exchange fluid, a second pressure reducing unit 14c for reducing the pressure of the refrigerant released by the heat sink, a second evaporator 19 for evaporating the refrigerant and cooling the cooling object by allowing the refrigerant reduced by the second pressure reducing unit to absorb heat from the object to be cooled 80, flow rate adjustment units 32 and 92 for adjusting the flow rate of the heat exchange fluid flowing through the first evaporator, and a control unit 60 for flow rate increase control which controls the flow rate adjustment unit to increase the flow rate of the heat exchange fluid when the cooling requirement level for the second evaporator side increases.

Description

Technical Field

[0001] The present invention relates to a refrigeration cycle that performs cooling simultaneously with two or more evaporators.

Background Art

[0002] Conventionally, Patent Document 1 describes that in a refrigeration cycle in which cooling is performed by an air-conditioning side evaporator and battery cooling is performed by a battery side evaporator, when the load of battery cooling is high, the air-conditioning load is reduced by reducing the air-conditioning air volume, thereby strengthening the cooling effect on the battery.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, according to the above prior art, since the temperature and pressure of the air-conditioning side evaporator decrease by reducing the air-conditioning air volume, the density of the refrigerant sucked by the compressor decreases, and the discharge flow rate of the compressor decreases. As a result, it is difficult to effectively increase the cooling capacity of the battery because the cooling capacity of the entire refrigeration cycle decreases.

[0005] In view of the above points, an object of the present invention is to effectively increase the cooling capacity of one evaporator side when the cooling requirement for one evaporator side increases in a refrigeration cycle that performs cooling simultaneously with two or more evaporators.

Means for Solving the Problems

[0006] To achieve the above object, the refrigeration cycle device according to claim 1 a compressor (11) that sucks, compresses, and discharges a refrigerant; A heat sink (12) that dissipates heat from the refrigerant discharged from the compressor, A first pressure reduction section (14b) reduces the pressure of the refrigerant that has been heated by the heat sink, A first evaporator (18, 25) that reduces the pressure of the refrigerant in the first depressurization section by allowing it to absorb heat from the heat exchange fluid, thereby evaporating the refrigerant and cooling the heat exchange fluid, A second pressure reduction section (14c) reduces the pressure of the refrigerant that has been heated by the heat sink, A second evaporator (19) that evaporates the refrigerant, which has been depressurized in the second pressure reduction section, by allowing it to absorb heat from the object to be cooled (80), and simultaneously cools the object to be cooled. A flow rate adjustment unit (32, 92) adjusts the flow rate of the heat exchange fluid flowing through the first evaporator, The system includes a control unit (60) that performs flow rate increase control, which controls the flow rate adjustment unit to increase the flow rate of the heat exchange fluid when the cooling requirement level for the second evaporator increases.

[0007] According to this, when the cooling requirement level for the second evaporator increases, the temperature and pressure of the first evaporator rise by increasing the flow rate of the heat exchange fluid to the first evaporator. This increases the density of the refrigerant drawn into the compressor, and thus increases the discharge flow rate of the compressor. As a result, the flow rate of refrigerant in the second evaporator increases, which effectively increases the cooling capacity of the second evaporator.

[0008] The reference numerals in parentheses next to each means described in this section and in the claims indicate the correspondence with the specific means described in the embodiments described later. [Brief explanation of the drawing]

[0009] [Figure 1] This is an overall configuration diagram showing a vehicle air conditioning system according to the first embodiment. [Figure 2] This is a block showing the electronic control unit of a vehicle air conditioning system according to the first embodiment. [Figure 3] This is a flowchart showing a portion of the control program of the first embodiment. [Figure 4] This flowchart shows another part of the control program of the first embodiment. [Figure 5] This diagram illustrates the battery cooling priority level determined in the control program of the first embodiment. [Figure 6] This diagram illustrates the airflow rate and target evaporator temperature determined by the battery cooling priority control in the control program of the first embodiment. [Figure 7] This graph illustrates the effects of battery cooling priority control in the first embodiment. [Figure 8] This graph shows the relationship between airflow rate and cooling capacity in the refrigeration cycle device of the first embodiment. [Figure 9] This is an overall configuration diagram showing a vehicle air conditioning system according to the second embodiment. [Figure 10] This is an overall configuration diagram showing a vehicle air conditioning system according to the third embodiment. [Figure 11] This is an overall configuration diagram showing a vehicle air conditioning system according to the fourth embodiment. [Figure 12] This is an overall configuration diagram showing a vehicle air conditioning system according to the fifth embodiment. [Modes for carrying out the invention]

[0010] (First Embodiment) A first embodiment will be described using Figures 1 to 8. In this embodiment, the refrigeration cycle device 10 is applied to a vehicle air conditioning system 1 mounted on an electric vehicle that obtains driving force from an electric motor. This vehicle air conditioning system 1 not only provides air conditioning for the vehicle interior, which is the space to be air-conditioned, but also has a function to adjust the temperature of the battery 80. For this reason, the vehicle air conditioning system 1 can also be called an air conditioning system with a battery temperature adjustment function.

[0011] The battery 80 is a secondary battery that stores power supplied to in-vehicle equipment such as electric motors. The battery 80 in this embodiment is a lithium-ion battery. The battery 80 is a so-called battery pack formed by stacking a plurality of battery cells 81 and electrically connecting these battery cells 81 in series or parallel.

[0012] This type of battery is likely to have a reduced output at low temperatures and its degradation is likely to progress at high temperatures. Therefore, the temperature of the battery needs to be maintained within an appropriate temperature range (in this embodiment, 15°C or higher and 55°C or lower) where the charge-discharge capacity of the battery can be fully utilized.

[0013] Therefore, in the vehicle air conditioner 1, the battery 80 can be cooled by the cooling heat generated by the refrigeration cycle device 10. Accordingly, the object to be cooled different from air in the refrigeration cycle device 10 of this embodiment is the battery 80.

[0014] As shown in the overall configuration diagram of FIG. 1, the vehicle air conditioner 1 includes a refrigeration cycle device 10, an indoor air conditioning unit 30, a high-temperature side heat medium circuit 40, a low-temperature side heat medium circuit 50, and the like.

[0015] The refrigeration cycle device 10 functions to cool the air blown into the vehicle interior for air conditioning in the vehicle interior, and to heat the high-temperature side heat medium circulating in the high-temperature side heat medium circuit 40. Further, the refrigeration cycle device 10 functions to cool the low-temperature side heat medium circulating in the low-temperature side heat medium circuit 50 in order to cool the battery 80.

[0016] The refrigeration cycle device 10 is configured to be able to switch refrigerant circuits for various operation modes for air conditioning in the vehicle interior. For example, it is configured to be able to switch a refrigerant circuit for the cooling mode, a refrigerant circuit for the dehumidifying heating mode, a refrigerant circuit for the heating mode, and the like. Further, the refrigeration cycle device 10 can switch between an operation mode for cooling the battery 80 and an operation mode for not cooling the battery 80 in each operation mode for air conditioning.

[0017] Furthermore, the refrigeration cycle device 10 employs an HFO-based refrigerant (specifically, R1234yf) as the refrigerant, and constitutes a vapor compression type subcritical refrigeration cycle in which the pressure of the discharged refrigerant discharged from the compressor 11 does not exceed the critical pressure of the refrigerant. In addition, refrigeration oil for lubricating the compressor 11 is mixed with the refrigerant. A portion of the refrigeration oil circulates in the cycle together with the refrigerant.

[0018] Among the components of the refrigeration cycle system 10, the compressor 11 is responsible for drawing in, compressing, and discharging refrigerant within the refrigeration cycle system 10. The compressor 11 is located in the drive unit chamber, which is situated at the front of the passenger compartment and houses the electric motor and other components. The compressor 11 is an electric compressor that rotates a fixed-capacity compression mechanism with a fixed discharge capacity using 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 60.

[0019] The discharge port of the compressor 11 is connected to the inlet side of the refrigerant passage of the water refrigerant heat exchanger 12. The water refrigerant heat exchanger 12 has a refrigerant passage through which the high-pressure refrigerant discharged from the compressor 11 flows, and a water passage through which the high-temperature heat transfer medium circulating in the high-temperature heat transfer medium circuit 40 flows. The water refrigerant heat exchanger 12 is a heating heat exchanger that heats the high-pressure refrigerant flowing through the refrigerant passage and the high-temperature heat transfer medium flowing through the water passage. The water refrigerant heat exchanger 12 is a heat radiator that releases heat from the refrigerant discharged from the compressor 11.

[0020] The outlet of the refrigerant passage of the water refrigerant heat exchanger 12 is connected to the inlet side of a first three-way joint 13a, which has three interconnected inlet and outlet connections. Such a three-way joint can be formed by joining multiple pipes, or by providing multiple refrigerant passages in a metal block or resin block.

[0021] Furthermore, the refrigeration cycle device 10 is equipped with second to sixth three-way joints 13b to 13f. The basic configuration of these second to sixth three-way joints 13b to 13f is the same as that of the first three-way joint 13a.

[0022] One outlet of the first three-way joint 13a is connected to the inlet side of the heating expansion valve 14a. The other outlet of the first three-way joint 13a is connected to the inlet side of the second three-way joint 13b via a bypass passage 22a. A dehumidifying on / off valve 15a is located in the bypass passage 22a.

[0023] The dehumidifying on / off valve 15a is a solenoid valve that opens and closes the refrigerant passage connecting the other outlet side of the first three-way joint 13a and one inlet side of the second three-way joint 13b. The dehumidifying on / off valve 15a is a bypass on / off section that opens and closes the bypass passage 22a.

[0024] Furthermore, the refrigeration cycle device 10 is equipped with a heating on / off valve 15b. The basic configuration of the heating on / off valve 15b is the same as that of the dehumidifying on / off valve 15a.

[0025] The dehumidifying valve 15a and the heating valve 15b can switch the refrigerant circuit for each operating mode by opening and closing the refrigerant passage. Therefore, the dehumidifying valve 15a and the heating valve 15b are refrigerant circuit switching devices that switch the refrigerant circuit of the cycle. The operation of the dehumidifying valve 15a and the heating valve 15b is controlled by the control voltage output from the control device 60.

[0026] The heating expansion valve 14a is a heating pressure reducing unit that reduces the pressure of the high-pressure refrigerant flowing out of the refrigerant passage of the water refrigerant heat exchanger 12 and adjusts the flow rate (mass flow rate) of the refrigerant flowing downstream, at least when the vehicle is operating in a mode that heats the interior of the vehicle. The heating expansion valve 14a is an electrically operated variable throttle mechanism that has a valve body configured to change the throttle opening and an electric actuator that changes the opening of the valve body.

[0027] Furthermore, the refrigeration cycle device 10 is equipped with a cooling expansion valve 14b and a defrosting expansion valve 14c. The basic configuration of the cooling expansion valve 14b and the defrosting expansion valve 14c is the same as that of the heating expansion valve 14a.

[0028] The heating expansion valve 14a, the cooling expansion valve 14b, and the cooling expansion valve 14c have a fully open function that functions as a simple refrigerant passage with almost no flow rate adjustment or refrigerant pressure reduction effect when the valve opening is fully open, and a fully closed function that blocks the refrigerant passage when the valve opening is fully closed.

[0029] Furthermore, these fully open and fully closed functions allow the heating expansion valve 14a, the cooling expansion valve 14b, and the cooling expansion valve 14c to switch the refrigerant circuits for each operating mode.

[0030] Therefore, the heating expansion valve 14a, the cooling expansion valve 14b, and the cooling expansion valve 14c of this embodiment also function as refrigerant circuit switching devices. The operation of the heating expansion valve 14a, the cooling expansion valve 14b, and the cooling expansion valve 14c is controlled by control signals (control pulses) output from the control device 60.

[0031] The heating expansion valve 14a is a throttle for the outdoor heat exchanger that can change the flow rate of the refrigerant flowing into the outdoor heat exchanger 16. The cooling expansion valve 14b is a throttle for the indoor evaporator that can change the flow rate of the refrigerant flowing into the indoor evaporator 18.

[0032] The heating expansion valve 14a and the cooling expansion valve 14b are first throttling sections that can change the flow rate of refrigerant flowing into the outdoor heat exchanger 16 and the indoor evaporator 18. The cooling expansion valve 14c is a second throttling section that can change the flow rate of refrigerant flowing into the chiller 19.

[0033] The outlet of the heating expansion valve 14a is connected to the refrigerant inlet side of the outdoor heat exchanger 16. The outdoor heat exchanger 16 is a heat exchanger that exchanges heat between the refrigerant flowing out from the heating expansion valve 14a and outside air blown by a cooling fan (not shown). The outdoor heat exchanger 16 is located on the front side of the drive unit room. Therefore, when the vehicle is running, the airflow from the vehicle can be directed onto the outdoor heat exchanger 16.

[0034] The outdoor heat exchanger 16 is a heat exchanger that releases heat from the refrigerant. The outdoor heat exchanger 16 is also a first evaporator that evaporates the refrigerant.

[0035] The first refrigerant passage 16a is a refrigerant passage that guides the refrigerant that has flowed out of the water refrigerant heat exchanger 12 to the inlet side of the outdoor heat exchanger 16.

[0036] The inlet side of the third three-way joint 13c is connected to the refrigerant outlet of the outdoor heat exchanger 16. One of the outlets of the third three-way joint 13c is connected to one of the inlet sides of the fourth three-way joint 13d via the heating passage 22b.

[0037] The heating passage 22b is a second refrigerant passage that guides the refrigerant flowing out from the outdoor heat exchanger 16 to the suction side of the compressor 11. A heating on / off valve 15b that opens and closes this refrigerant passage is located in the heating passage 22b. The heating on / off valve 15b is a second refrigerant passage opening / closing unit that opens and closes the second refrigerant passage.

[0038] The other outlet of the third three-way joint 13c is connected to the other inlet side of the second three-way joint 13b. A check valve 17 is placed in the refrigerant passage connecting the other outlet side of the third three-way joint 13c and the other inlet side of the second three-way joint 13b. The check valve 17 allows refrigerant to flow from the third three-way joint 13c side to the second three-way joint 13b side and prevents refrigerant from flowing from the second three-way joint 13b side to the third three-way joint 13c side.

[0039] The outlet of the second three-way joint 13b is connected to the inlet side of the fifth three-way joint 13e. One outlet of the fifth three-way joint 13e is connected to the inlet side of the cooling expansion valve 14b. The other outlet of the fifth three-way joint 13e is connected to the inlet side of the cooling expansion valve 14c.

[0040] The cooling expansion valve 14b is a heating pressure reducing unit that reduces the pressure of the refrigerant flowing out from the outdoor heat exchanger 16 and adjusts the flow rate of the refrigerant flowing downstream, at least when the vehicle is in an operating mode that provides cooling to the interior of the vehicle.

[0041] The outlet of the cooling expansion valve 14b is connected to the refrigerant inlet side of the indoor evaporator 18. The indoor evaporator 18 is located inside the air conditioning case 31 of the indoor air conditioning unit 30. The indoor evaporator 18 is a cooling heat exchanger that cools the air by exchanging heat between the low-pressure refrigerant, which has been reduced in pressure by the cooling expansion valve 14b, and the air (i.e., heat exchange fluid) blown from the blower 32, thereby evaporating the low-pressure refrigerant and causing it to exhibit an endothermic effect.

[0042] The inlet side of the evaporation pressure regulating valve 20 is connected to the refrigerant outlet of the indoor evaporator 18. One inlet side of the sixth three-way joint 13f is connected to the outlet of the evaporation pressure regulating valve 20. The evaporation pressure regulating valve 20 functions to maintain the refrigerant evaporation pressure in the indoor evaporator 18 at or above a predetermined reference pressure in order to suppress frost formation in the indoor evaporator 18. The evaporation pressure regulating valve 20 is composed of a mechanical variable throttling mechanism that increases the valve opening in response to an increase in the pressure of the refrigerant on the outlet side of the indoor evaporator 18. As a result, the evaporation pressure regulating valve 20 maintains the refrigerant evaporation temperature in the indoor evaporator 18 at or above a frost suppression temperature (1°C in this embodiment) that can suppress frost formation in the indoor evaporator 18.

[0043] The cooling expansion valve 14c is a cooling pressure reduction unit that reduces the pressure of the refrigerant flowing out of the outdoor heat exchanger 16 and adjusts the flow rate of the refrigerant flowing downstream, at least when the operating mode is used to cool the battery 80.

[0044] The outlet of the cooling expansion valve 14c is connected to the inlet side of the refrigerant passage of the chiller 19. The chiller 19 has a refrigerant passage through which the low-pressure refrigerant, which has been reduced in pressure by the cooling expansion valve 14c, flows, and a water passage through which the low-temperature heat transfer medium that circulates in the low-temperature heat transfer medium circuit 50 flows. The chiller 19 is a second evaporator that causes heat exchange between the low-pressure refrigerant flowing through the refrigerant passage and the low-temperature heat transfer medium flowing through the water passage, thereby evaporating the low-pressure refrigerant and exhibiting an endothermic effect. The outlet of the refrigerant passage of the chiller 19 is connected to the other inlet side of the sixth three-way joint 13f.

[0045] The outlet of the sixth three-way joint 13f is connected to the other inlet side of the fourth three-way joint 13d. The outlet of the fourth three-way joint 13d is connected to the inlet side of the accumulator 21. The accumulator 21 is a gas-liquid separator that separates the gaseous and liquid phases of the refrigerant flowing into it and stores the excess liquid phase refrigerant in the cycle. The gaseous phase refrigerant outlet of the accumulator 21 is connected to the suction side of the compressor 11.

[0046] The third refrigerant passage 18a is a refrigerant passage that guides the refrigerant flowing out from the outdoor heat exchanger 16 to the suction side of the compressor 11 via the evaporator 18.

[0047] The battery cooling passage 19a is a refrigerant passage that guides the refrigerant flowing between the outdoor heat exchanger 16 and the cooling expansion valve 14b to the third refrigerant passage 18 between the indoor evaporator 18 and the suction side of the compressor 11 via the chiller 19.

[0048] As is clear from the above description, the fifth three-way joint 13e in this embodiment functions as a branching section that branches the flow of refrigerant discharged from the outdoor heat exchanger 16. The sixth three-way joint 13f is a confluence section that combines the flow of refrigerant discharged from the indoor evaporator 18 and the flow of refrigerant discharged from the chiller 19 and discharges them to the suction side of the compressor 11.

[0049] The indoor evaporator 18 and chiller 19 are connected in parallel to each other with respect to the refrigerant flow. Furthermore, the bypass passage 22a guides the refrigerant that has flowed out of the refrigerant passage of the water refrigerant heat exchanger 12 to the upstream side of the branching section. The heating passage 22b guides the refrigerant that has flowed out of the outdoor heat exchanger 16 to the intake side of the compressor 11.

[0050] Next, the high-temperature side heat transfer medium circuit 40 will be described. The high-temperature side heat transfer medium circuit 40 is a heat transfer medium circulation circuit that circulates the high-temperature side heat transfer medium. As the high-temperature side heat transfer medium, solutions containing ethylene glycol, dimethylpolysiloxane, nanofluids, antifreeze, etc., can be used. The high-temperature side heat transfer medium circuit 40 is equipped with a water passage for the water refrigerant heat exchanger 12, a high-temperature side heat transfer medium pump 41, a heater core 42, etc.

[0051] The high-temperature side heat transfer fluid pump 41 is a water pump that pressurizes the high-temperature side heat transfer fluid to the inlet side of the water passage of the water refrigerant heat exchanger 12. The high-temperature side heat transfer fluid pump 41 is an electric pump whose rotational speed (i.e., pumping capacity) is controlled by a control voltage output from the control device 60.

[0052] The outlet of the water passage of the water refrigerant heat exchanger 12 is connected to the heat transfer medium inlet side of the heater core 42. The heater core 42 is a heat exchanger that heats the air by exchanging heat between the high-temperature heat transfer medium heated in the water refrigerant heat exchanger 12 and the air that has passed through the indoor evaporator 18. The heater core 42 is located inside the air conditioning case 31 of the indoor air conditioning unit 30. The outlet of the heat transfer medium of the heater core 42 is connected to the suction port side of the high-temperature heat transfer medium pump 41.

[0053] Therefore, in the high-temperature heat transfer medium circuit 40, the high-temperature heat transfer medium pump 41 can adjust the amount of heat released from the high-temperature heat transfer medium into the heater core 42, that is, the amount of heat heated in the heater core 42, by adjusting the flow rate of the high-temperature heat transfer medium flowing into the heater core 42.

[0054] In other words, in this embodiment, the water refrigerant heat exchanger 12 and the high-temperature side heat transfer medium circuit 40 constitute a heating unit that heats air using the refrigerant discharged from the compressor 11 as a heat source.

[0055] Next, the low-temperature side heat transfer medium circuit 50 will be described. The low-temperature side heat transfer medium circuit 50 is a heat transfer medium circulation circuit that circulates the low-temperature side heat transfer medium. The same fluid as the high-temperature side heat transfer medium can be used as the low-temperature side heat transfer medium. The low-temperature side heat transfer medium circuit 50 is equipped with a water passage for the chiller 19, a low-temperature side heat transfer medium pump 51, a cooling heat exchange section 52, a three-way valve 53, a low-temperature side radiator 54, and the like.

[0056] The low-temperature side heat transfer fluid pump 51 is a water pump that pumps the low-temperature side heat transfer fluid to the inlet side of the water passage of the chiller 19. The basic configuration of the low-temperature side heat transfer fluid pump 51 is the same as that of the high-temperature side heat transfer fluid pump 41.

[0057] The outlet of the water passage of the chiller 19 is connected to the inlet side of the cooling heat exchange unit 52. The cooling heat exchange unit 52 has multiple metal heat transfer fluid channels arranged to contact multiple battery cells 81 (in other words, objects that absorb heat) that make up the battery 80. The heat exchange unit cools the battery 80 by exchanging heat between the low-temperature heat transfer fluid flowing through the heat transfer fluid channels and the battery cells 81.

[0058] Such a cooling heat exchange section 52 can be formed by arranging a heat transfer medium channel between stacked battery cells 81. Alternatively, the cooling heat exchange section 52 may be integrally formed with the battery 80. For example, it may be integrally formed with the battery 80 by providing a heat transfer medium channel in a dedicated case that houses the stacked battery cells 81.

[0059] The outlet of the cooling heat exchange section 52 is connected to the inlet side of a three-way valve 53. The three-way valve 53 is an electrically operated three-way flow control valve having one inlet and two outlets, and capable of continuously adjusting the ratio of the passage areas of the two outlets. The operation of the three-way valve 53 is controlled by a control signal output from the control device 60.

[0060] One outlet of the three-way valve 53 is connected to the heat transfer medium inlet side of the low-temperature side radiator 54. The other outlet of the three-way valve 53 is connected to the suction port side of the low-temperature side heat transfer medium pump 51 via the radiator bypass passage 53a.

[0061] The radiator bypass channel 53a is a heat transfer medium channel through which the low-temperature heat transfer medium that has flowed out of the cooling heat exchange section 52 bypasses the low-temperature radiator 54.

[0062] Therefore, the three-way valve 53 plays the function of continuously adjusting the flow rate of the low-temperature heat transfer medium that flows from the cooling heat exchange unit 52 into the low-temperature radiator 54 in the low-temperature heat transfer medium circuit 50.

[0063] The low-temperature side radiator 54 is a heat exchanger that exchanges heat between the refrigerant flowing out from the cooling heat exchange section 52 and outside air blown by an outside air fan (not shown), thereby releasing the heat contained in the low-temperature side heat transfer medium to the outside air.

[0064] The low-temperature side radiator 54 is located on the front side of the drive unit compartment. Therefore, when the vehicle is running, the airflow from the vehicle can be directed onto the low-temperature side radiator 54. Accordingly, the low-temperature side radiator 54 may be integrally formed with the outdoor heat exchanger 16, etc. The inlet side of the low-temperature side heat transfer medium pump 51 is connected to the heat transfer medium outlet of the low-temperature side radiator 54.

[0065] Therefore, in the low-temperature heat transfer medium circuit 50, the low-temperature heat transfer medium pump 51 adjusts the flow rate of the low-temperature heat transfer medium flowing into the cooling heat exchange section 52, thereby adjusting the amount of heat absorbed by the low-temperature heat transfer medium in the cooling heat exchange section 52 from the battery 80. In other words, in this embodiment, the chiller 19 and the components of the low-temperature heat transfer medium circuit 50 constitute a cooling section that cools the battery 80 by evaporating the refrigerant that has flowed out from the cooling expansion valve 14c.

[0066] Next, the interior air conditioning unit 30 will be described. The interior air conditioning unit 30 is for blowing air whose temperature has been adjusted by the refrigeration cycle device 10 into the vehicle interior. The interior air conditioning unit 30 is located inside the instrument panel at the very front of the vehicle interior.

[0067] As shown in Figure 1, the indoor air conditioning unit 30 houses a blower 32, an indoor evaporator 18, a heater core 42, and the like within an air passage formed inside an air conditioning case 31 that forms its outer shell.

[0068] The air conditioning case 31 forms an air passage for air that is blown into the vehicle interior. The air conditioning case 31 is molded from a resin (for example, polypropylene) that has a certain degree of elasticity and excellent strength.

[0069] An internal / external air switching device 33 is located at the upstream end of the airflow in the air conditioning case 31. The internal / external air switching device 33 switches between introducing internal air (inside the vehicle) and outside air (outside the vehicle) into the air conditioning case 31.

[0070] The internal / external air switching device 33 continuously adjusts the opening area of ​​the internal air inlet for introducing internal air and the external air inlet for introducing external air into the air conditioning case 31 using the internal / external air switching door, thereby changing the ratio of internal air intake volume to external air intake volume. The internal / external air switching door is driven by an electric actuator for the internal / external air switching door. The operation of this electric actuator is controlled by a control signal output from the control device 60.

[0071] A blower 32 is positioned downstream of the airflow of the internal / external air switching device 33. The blower 32 blows the air drawn in through the internal / external air switching device 33 into the vehicle interior. The blower 32 is an electric blower that drives a centrifugal multi-blade fan with an electric motor. The rotational speed (i.e., the blowing capacity) of the blower 32 is controlled by a control voltage output from the control device 60.

[0072] Downstream of the airflow from the blower 32, the indoor evaporator 18 and the heater core 42 are arranged in this order relative to the airflow. In other words, the indoor evaporator 18 is located upstream of the heater core 42 in the airflow.

[0073] A cold air bypass passage 35 is provided inside the air conditioning case 31, which allows the air that has passed through the indoor evaporator 18 to flow around the heater core 42. An air mix door 34 is located downstream of the airflow of the indoor evaporator 18 inside the air conditioning case 31, and upstream of the airflow of the heater core 42.

[0074] The air mix door 34 is an airflow ratio adjustment unit that adjusts the airflow ratio between the airflow that passes through the heater core 42 side and the airflow that passes through the cold air bypass passage 35, after the air has passed through the indoor evaporator 18. The air mix door 34 is driven by an electric actuator for the air mix door. The operation of this electric actuator is controlled by a control signal output from the control device 60.

[0075] A mixing space is located downstream of the airflow from the heater core 42 and the cold air bypass passage 35 within the air conditioning case 31. The mixing space is a space where air heated by the heater core 42 is mixed with unheated air that has passed through the cold air bypass passage 35.

[0076] Furthermore, an opening is provided in the downstream part of the airflow of the air conditioning case 31 for blowing the air mixed in the mixing space (i.e., conditioned air) into the vehicle interior, which is the space to be air-conditioned.

[0077] These openings include a face opening, a foot opening, and a defroster opening (none of which are shown). The face opening is for blowing conditioned air towards the upper body of the occupant inside the vehicle. The foot opening is for blowing conditioned air towards the occupant's feet. The defroster opening is for blowing conditioned air towards the inner surface of the vehicle's front window glass.

[0078] These face openings, foot openings, and defroster openings are connected to face outlets, foot outlets, and defroster outlets (none of which are shown) located inside the vehicle cabin, via ducts that form air passages.

[0079] Therefore, the air mix door 34 adjusts the ratio of the airflow passing through the heater core 42 to the airflow passing through the cold air bypass passage 35, thereby adjusting the temperature of the conditioned air mixed in the mixing space. This adjusts the temperature of the air (conditioned air) blown into the passenger compartment from each outlet.

[0080] Furthermore, face doors, foot doors, and defroster doors (none of which are shown) are positioned upstream of the airflow to the face opening, foot opening, and defroster opening, respectively. The face doors adjust the opening area of ​​the face opening. The foot doors adjust the opening area of ​​the foot opening. The defroster doors adjust the opening area of ​​the froster opening.

[0081] These face doors, foot doors, and defroster doors constitute an air outlet mode switching device that switches between air outlet modes. These doors are connected via a linkage mechanism to an electric actuator for driving the air outlet mode door and are rotated in conjunction with it. The operation of this electric actuator is also controlled by a control signal output from the control device 60.

[0082] The outlet modes that can be switched using the outlet mode switching device include, specifically, face mode, bi-level mode, and foot mode.

[0083] Face mode is an air outlet mode in which the face vents are fully open and air is blown from the face vents toward the upper body of the occupant in the vehicle. Bi-level mode is an air outlet mode in which both the face vents and foot vents are opened and air is blown toward the upper body and feet of the occupant in the vehicle. Foot mode is an air outlet mode in which the foot vents are fully open and the defroster vents are opened only slightly, and air is mainly blown from the foot vents.

[0084] Furthermore, the occupant can switch to defroster mode by manually operating the air outlet mode switch located on the control panel 70. Defroster mode is an air outlet mode in which the defroster vents are fully open and air is blown from the defroster vents onto the inner surface of the front windshield.

[0085] Next, an overview of the electrical control unit of this embodiment will be described. The control device 60 is a control unit composed of a well-known microcomputer including a CPU, ROM, and RAM, and its peripheral circuits. The control device 60 performs various calculations and processes based on the control program stored in its ROM, and controls the operation of various controlled devices 11, 14a to 14c, 15a, 15b, 32, 41, 51, 53, etc. connected to its output side.

[0086] Furthermore, as shown in the block diagram in Figure 2, the input side of the control device 60 is connected to an internal temperature sensor 61, an external temperature sensor 62, a solar radiation sensor 63, first to fifth refrigerant temperature sensors 64a to 64e, an evaporator temperature sensor 64f, first to second refrigerant pressure sensors 65a to 65b, a high-temperature side heat transfer medium temperature sensor 66a, first to second low-temperature side heat transfer medium temperature sensors 67a to 67b, an air conditioning air temperature sensor 68, a battery control device 82, and the like. The detection signals from these sensors are then input to the control device 60.

[0087] The interior temperature sensor 61 is an interior temperature detection unit that detects the temperature inside the vehicle (interior temperature) Tr. The exterior temperature sensor 62 is an exterior temperature detection unit that detects the temperature outside the vehicle (outside temperature) Tam. The solar radiation sensor 63 is a solar radiation detection unit that detects the amount of solar radiation Ts irradiated into the vehicle interior.

[0088] The first refrigerant temperature sensor 64a is a discharge refrigerant temperature detection unit that detects the temperature T1 of the refrigerant discharged from the compressor 11. The second refrigerant temperature sensor 64b is a second refrigerant temperature detection unit that detects the temperature T2 of the refrigerant that has flowed out from the refrigerant passage of the water refrigerant heat exchanger 12. The third refrigerant temperature sensor 64c is a third refrigerant temperature detection unit that detects the temperature T3 of the refrigerant that has flowed out from the outdoor heat exchanger 16.

[0089] The fourth refrigerant temperature sensor 64d is a fourth refrigerant temperature detection unit that detects the temperature T4 of the refrigerant that has flowed out from the indoor evaporator 18. The fifth refrigerant temperature sensor 64e is a fifth refrigerant temperature detection unit that detects the temperature T5 of the refrigerant that has flowed out from the refrigerant passage of the chiller 19.

[0090] The evaporator temperature sensor 64f is an evaporator temperature detection unit that detects the refrigerant evaporation temperature (evaporator temperature) Tefin in the indoor evaporator 18. Specifically, the evaporator temperature sensor 64f in this embodiment detects the heat exchange fin temperature of the indoor evaporator 18.

[0091] The first refrigerant pressure sensor 65a is a first refrigerant pressure detection unit that detects the pressure P1 of the refrigerant flowing out of the refrigerant passage of the water refrigerant heat exchanger 12. The second refrigerant pressure sensor 65b is a second refrigerant pressure detection unit that detects the pressure P2 of the refrigerant flowing out of the refrigerant passage of the chiller 19.

[0092] The high-temperature side heat transfer medium temperature sensor 66a is a high-temperature side heat transfer medium temperature detection unit that detects the high-temperature side heat transfer medium temperature TWH, which is the temperature of the high-temperature side heat transfer medium that has flowed out from the water passage of the water refrigerant heat exchanger 12.

[0093] The first low-temperature side heat transfer medium temperature sensor 67a is a first low-temperature side heat transfer medium temperature detection unit that detects the first low-temperature side heat transfer medium temperature TWL1, which is the temperature of the low-temperature side heat transfer medium that has flowed out from the water passage of the chiller 19. The first low-temperature side heat transfer medium temperature TWL1 is a temperature related to the temperature of the chiller 19.

[0094] The second low-temperature side heat transfer medium temperature sensor 67b is a second low-temperature side heat transfer medium temperature detection unit that detects the second low-temperature side heat transfer medium temperature TWL2, which is the temperature of the low-temperature side heat transfer medium that has flowed out from the cooling heat exchange unit 52.

[0095] The air conditioning air temperature sensor 68 is an air conditioning air temperature detection unit that detects the TAV (Time Atmosphere Value) of the air blown from the mixing space into the vehicle interior.

[0096] The battery control device 82 is a battery control unit that controls the input and output of the battery 80, and is composed of a well-known microcomputer including a CPU, ROM, and RAM, and its peripheral circuits. The battery control device 82 performs various calculations and processes based on the control program stored in its ROM, and controls the input and output of the battery 80.

[0097] A battery temperature sensor 83 is connected to the input side of the battery control device 82. The battery temperature sensor 83 is a battery temperature detection unit that detects the battery temperature TB (i.e., the temperature of the battery 80). The battery temperature sensor 83 in this embodiment has multiple temperature sensors and detects the temperature at multiple locations on the battery 80. Therefore, the control device 60 can also detect temperature differences at various parts of the battery 80. The average value of the detected values ​​from the multiple temperature sensors is used as the battery temperature TB.

[0098] The battery control device 82 determines whether or not the battery 80 needs to be cooled based on the battery temperature TB detected by the battery temperature sensor 83. If the battery control device 82 determines that the battery 80 needs to be cooled, it outputs a battery cooling request signal to the control device 60.

[0099] Furthermore, as shown in Figure 2, an operation panel 70 located near the instrument panel at the front of the vehicle interior is connected to the input side of the control device 60, and operation signals from various operation switches provided on this operation panel 70 are input.

[0100] The various operation switches provided on the control panel 70 include, specifically, an auto switch for setting or canceling the automatic control operation of the vehicle's air conditioning system, an air conditioner switch for requesting that the indoor evaporator 18 cool the air, an airflow setting switch for manually setting the airflow of the blower 32, a temperature setting switch for setting the target temperature Tset inside the vehicle, and an airflow mode switching switch for manually setting the airflow mode.

[0101] In this embodiment, the control device 60 has a control unit integrated with it that controls various controlled devices connected to its output side. 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.

[0102] For example, the configuration of the control device 60 that controls the refrigerant discharge capacity of the compressor 11 (specifically, the rotational speed of the compressor 11) constitutes the compressor control unit 60a. The configuration of the control device 60 that controls the operation of the heating expansion valve 14a, the cooling expansion valve 14b, and the cooling expansion valve 14c constitutes the expansion valve control unit 60b. The configuration of the control device 60 that controls the operation of the dehumidifying on / off valve 15a and the heating on / off valve 15b constitutes the refrigerant circuit switching control unit 60c.

[0103] Of the control devices 60, the configuration that controls the pumping capacity of the high-temperature side heat transfer medium in the high-temperature side heat transfer medium pump 41 constitutes the high-temperature side heat transfer medium pump control unit 60d. Of the control devices 60, the configuration that controls the pumping capacity of the low-temperature side heat transfer medium in the low-temperature side heat transfer medium pump 51 constitutes the low-temperature side heat transfer medium pump control unit 60e.

[0104] Next, the operation of this embodiment in the above configuration will be described. As mentioned above, the vehicle air conditioning system 1 of this embodiment not only provides air conditioning in the vehicle cabin but also has the function of adjusting the temperature of the battery 80. For this reason, the refrigeration cycle system 10 can switch the refrigerant circuit to operate in the following 11 operating modes.

[0105] (1) Cooling mode: Cooling mode is an operating mode that cools the interior of the vehicle by cooling the air and blowing it into the vehicle interior without cooling the battery 80.

[0106] (2) Series dehumidifying heating mode: The series dehumidifying heating mode is an operating mode that dehumidifies and heats the interior of the vehicle by reheating the cooled and dehumidified air and blowing it into the vehicle interior without cooling the battery 80.

[0107] (3) Parallel dehumidifying and heating mode: The parallel dehumidifying and heating mode is an operating mode that dehumidifies and heats the interior of the vehicle by reheating the cooled and dehumidified air with a higher heating capacity than the series dehumidifying and heating mode and blowing it into the vehicle interior, without cooling the battery 80.

[0108] (4) Heating mode: Heating mode is an operating mode that heats the interior of the vehicle by heating the air and blowing it into the vehicle interior without cooling the battery 80.

[0109] (5) Cooling mode: The cooling mode is an operating mode that cools the battery 80 and cools the air inside the vehicle by blowing it into the vehicle interior.

[0110] (6) Series dehumidifying heating and cooling mode: The series dehumidifying heating and cooling mode is an operating mode that cools the battery 80 and reheats the cooled and dehumidified air and blows it into the vehicle interior to dehumidify and heat the vehicle interior.

[0111] (7) Parallel dehumidifying heating and cooling mode: The parallel dehumidifying heating and cooling mode is an operating mode that cools the battery 80 and reheats the cooled and dehumidified air with a higher heating capacity than the series dehumidifying heating and cooling mode, and blows it into the vehicle interior to dehumidify and heat the vehicle interior.

[0112] (8) Heating and Cooling Mode: The heating and cooling mode is an operating mode that cools the battery 80 and heats the air and blows it into the vehicle interior to heat the interior.

[0113] (9) Heating series cooling mode: The heating series cooling mode is an operating mode that cools the battery 80 and heats the air with a higher heating capacity than the heating cooling mode and blows it into the vehicle interior to heat the interior.

[0114] (10) Heating parallel cooling mode: The heating parallel cooling mode is an operating mode that cools the battery 80 and heats the air with a higher heating capacity than the heating series cooling mode and blows it into the vehicle interior to heat the interior.

[0115] (11) Cooling mode: This is an operating mode in which the battery 80 is cooled without using the air conditioning in the vehicle cabin.

[0116] These driving modes are switched by the execution of a control program. The control program is executed when the auto switch on the control panel 70 is turned ON by the occupant's operation, and automatic control within the vehicle cabin is set. The control program will be explained using Figures 3 and 4. Furthermore, each control step shown in the flowchart in Figure 3, etc., is a function implementation unit of the control device 60.

[0117] First, in step S100 shown in Figure 3, it is determined whether or not there is a request for cooling, that is, whether or not there is a request to cool the air with the indoor evaporator 18. Specifically, if the air conditioner switch on the control panel 70 is ON, it is determined that there is a request for cooling.

[0118] If it is determined in step S100 that there is no air conditioning request, the process proceeds to step S110, where it is determined whether or not there is a battery cooling request. Specifically, if a battery cooling request signal is input from the battery control device 82, it is determined that there is a battery cooling request.

[0119] If it is determined in step S110 that there is a battery cooling request, the process proceeds to step S120, and the refrigerant circuit is switched to cooling mode. If it is determined in step S110 that there is no battery cooling request, the process proceeds to step S130, and the operation of the refrigeration cycle device 10 is stopped.

[0120] If it is determined in step S100 that there is a cooling request, the process proceeds to step S140, where it is determined whether or not there is a battery cooling request, similar to step S110. If it is determined in step S140 that there is no battery cooling request, the process proceeds to step S150, where the refrigerant circuit is switched to cooling mode.

[0121] If it is determined in step S140 that there is a battery cooling request, the process proceeds to step S160, and the refrigerant circuit is switched to the cooling mode.

[0122] In step S170, it is determined whether the cooling capacity and battery cooling capacity have reached the target. For example, whether the cooling capacity has reached the target is determined based on the evaporator temperature Tefin detected by the evaporator temperature sensor 64f. For example, whether the battery cooling capacity has reached the target is determined based on the first low-temperature side heat transfer medium temperature TWL1 detected by the first low-temperature side heat transfer medium temperature sensor 67a.

[0123] If the cooling requirement level for the battery 80, i.e., the cooling capacity for the chiller 19, increases, it is possible that the cooling capacity or battery cooling capacity may become insufficient to meet the requirement and fail to reach the target.

[0124] If it is determined in step S170 that the cooling capacity and battery cooling capacity have not reached the target, the process proceeds to step S180, where it is determined whether there is room to increase the overall cooling capacity of the refrigeration cycle through normal control.

[0125] For example, if the rotational speed of the compressor 11 is near its upper limit, the superheat degree SHC of the refrigerant flowing out of the refrigerant passage of the chiller 19 is near its maximum value, the proportion of indoor air introduced into the indoor air conditioning unit 30 is near its maximum value, and the amount of air supplied to the outdoor heat exchanger 16 is near its upper limit, it is determined that there is no room to increase the overall cooling capacity of the refrigeration cycle through normal control.

[0126] If it is determined in step S180 that there is room to increase the overall cooling capacity of the refrigeration cycle through normal control, the process proceeds to step S190. Also, if it is determined in step S170 that the cooling capacity and battery cooling capacity have reached the target, the process proceeds to step S190.

[0127] In step S190, normal control of the cooling mode is performed and the process proceeds to step S220. In step S170, if the operation of the refrigeration cycle device 10 is in a transitional period, for example, during cool-down or warm-up, the process may proceed to step S190 if it is assumed that the cooling capacity and battery cooling capacity are likely to reach the target.

[0128] In the normal control of the cooling mode in step S190, the control device 60 executes the control flow shown in Figure 4. First, in step S1100, the target evaporator temperature TEO is determined. The target evaporator temperature TEO is the target temperature of the indoor evaporator 18 and is determined by referring to a control map stored in the control device 60 based on the target discharge temperature TAO. In the control map of this embodiment, it is determined that the target evaporator temperature TEO increases as the target discharge temperature TAO increases.

[0129] The target discharge temperature (TAO) is the target temperature of the air blown into the vehicle cabin, and is calculated using the following formula F1. TAO=Kset×Tset-Kr×Tr-Kam×Tam-Ks×Ts+C…(F1) Tset is the in-cabin temperature set by the temperature setting switch. Tr is the in-cabin temperature detected by the interior air sensor. Tam is the exterior temperature detected by the exterior air sensor. Ts is the solar radiation amount detected by the solar radiation sensor. Kset, Kr, Kam, and Ks are control gains, and C is a correction constant.

[0130] In step S1110, the amount of increase or decrease ΔIVO of the rotational speed of the compressor 11 is determined. The amount of increase or decrease ΔIVO is determined by a feedback control method based on the deviation between the target evaporator temperature TEO and the evaporator temperature Tefin detected by the evaporator temperature sensor 64f, so that the evaporator temperature Tefin approaches the target evaporator temperature TEO.

[0131] In step S1120, the target subcooling degree SCO1 of the refrigerant flowing out from the outdoor heat exchanger 16 is determined. The target subcooling degree SCO1 is determined by referring to a control map, for example, based on the outside temperature Tam. In the control map of this embodiment, the target subcooling degree SCO1 is determined so that the coefficient of performance (COP) of the cycle approaches a maximum value.

[0132] In step S1130, the amount of increase or decrease ΔEVC of the throttle opening of the cooling expansion valve 14b is determined. The amount of increase or decrease ΔEVC is determined by a feedback control method based on the deviation between the target subcooling degree SCO1 and the subcooling degree SC1 of the refrigerant on the outlet side of the outdoor heat exchanger 16, so that the subcooling degree SC1 of the refrigerant on the outlet side of the outdoor heat exchanger 16 approaches the target subcooling degree SCO1.

[0133] The degree of subcooling SC1 of the refrigerant on the outlet side of the outdoor heat exchanger 16 is calculated based on the temperature T3 detected by the third refrigerant temperature sensor 64c and the pressure P1 detected by the first refrigerant pressure sensor 65a.

[0134] In step S1140, the opening degree SW of the air mix door 34 is calculated using the following formula F2. SW={TAO-(Tefin+C2)} / {TWH-(Tefin+C2)}…(F2) TWH is the high-temperature side heat transfer medium temperature detected by the high-temperature side heat transfer medium temperature sensor 66a. C2 is a control constant.

[0135] Next, in step S1150, the target superheat SHCO of the refrigerant at the outlet of the refrigerant passage of the chiller 19 is determined. A predetermined constant (5°C in this embodiment) can be used as the target superheat SHCO.

[0136] In step S1160, the amount of increase or decrease ΔEVB of the throttling opening of the cooling expansion valve 14c is determined. In the cooling mode, the amount of increase or decrease ΔEVB is determined by a feedback control method based on the deviation between the target superheat SHCO and the superheat SHC of the refrigerant flowing out of the refrigerant passage of the chiller 19, so that the superheat SHC of the refrigerant flowing out of the refrigerant passage of the chiller 19 approaches the target superheat SHCO.

[0137] The degree of superheat SHC of the refrigerant flowing out of the refrigerant passage of chiller 19 is calculated based on the temperature T5 detected by the fifth refrigerant temperature sensor 64e and the pressure P2 detected by the second refrigerant pressure sensor 65b.

[0138] In step S1170, the target low-temperature heat transfer medium temperature TWLO of the low-temperature heat transfer medium that has flowed out of the water passage of the chiller 19 is determined. The target low-temperature heat transfer medium temperature TWLO is set to a first fixed value TWLO1 that is pre-stored in the control device 60.

[0139] In step S1180, it is determined whether the first low-temperature side heat medium temperature TWL1 detected by the first low-temperature side heat medium temperature sensor 67a is higher than the target low-temperature side heat medium temperature TWLO.

[0140] In step S1180, if it is determined that the first low-temperature side heat transfer medium temperature TWL1 is higher than the target low-temperature side heat transfer medium temperature TWLO, the process proceeds to step S1200. If it is not determined that the first low-temperature side heat transfer medium temperature TWL1 is higher than the target low-temperature side heat transfer medium temperature TWLO, the process proceeds to step S1190. In step S1190, the cooling expansion valve 14c is closed completely.

[0141] In step S1200, the airflow rate Va (so-called blower airflow rate) of the blower 32 is determined based on the target discharge temperature TAO. Specifically, in the extremely low temperature range (below -20°C in this embodiment) and the extremely high temperature range (above 80°C in this embodiment) of the target discharge temperature TAO, the airflow rate of the blower 32 is determined to be near the maximum airflow rate.

[0142] When the target discharge temperature TAO rises from the extremely low temperature range to the intermediate temperature range, the airflow rate of the blower 32 is reduced in accordance with the increase in the target discharge temperature TAO. When the target discharge temperature TAO falls from the extremely high temperature range to the intermediate temperature range, the airflow rate of the blower 32 is reduced in accordance with the decrease in the target discharge temperature TAO.

[0143] When the target discharge temperature TAO falls within a predetermined intermediate temperature range (10°C to 38°C in this embodiment), the airflow rate of the blower 32 is reduced to a low airflow rate. This determines the airflow rate Va of the blower 32 according to the air conditioning heat load.

[0144] If, in step S180 shown in Figure 3, it is determined that there is no room to increase the overall cooling capacity of the refrigeration cycle through normal control, the process proceeds to step S200 to determine the battery cooling priority level. In this example, as shown in Figure 5, the battery cooling priority level is determined based on the results of the battery 80 cooling requirement determination (hereinafter referred to as the battery cooling determination) and the air conditioning requirement determination. The battery cooling determination is performed based on the battery temperature TB, and the air conditioning requirement determination is performed based on the temperature difference obtained by subtracting the cabin temperature set Tset from the ambient temperature Tr.

[0145] Specifically, the higher the battery temperature TB, the higher the battery cooling priority level is determined to be, and the larger the temperature difference obtained by subtracting the cabin temperature Tset from the ambient temperature Tr, the lower the battery cooling priority level is determined to be. In other words, the higher the cooling requirement of the battery 80, the higher the battery cooling priority level is determined to be, the higher the cooling requirement, the lower the battery cooling priority level is determined to be, and if the cooling requirement and cooling requirement of the battery 80 are in the middle, it is determined to be in the middle level (Mid).

[0146] In step S210, battery cooling priority control is performed based on the battery cooling priority level determined in step S200. In battery cooling priority control, the control is basically the same as the normal control described in step S190, but the airflow rate Va of the blower 32 and the target evaporator temperature TEO are controlled differently from the normal control.

[0147] In this example, as shown in Figure 6, when the battery cooling priority level is Low, the airflow rate Va of the blower 32 is set to the normal control airflow rate Van, and when the battery cooling priority level is Mid or High, the airflow rate Va of the blower 32 is set to the battery cooling priority airflow rate Vam. The battery cooling priority airflow rate Vam is an airflow rate that is a predetermined amount higher than the normal control airflow rate Van.

[0148] Therefore, when the battery cooling priority level is Mid or High, the airflow rate through the indoor evaporator 18 increases compared to when the battery cooling priority level is Low. In other words, battery cooling priority control is a flow rate increase control that increases the airflow rate through the indoor evaporator 18 compared to normal control.

[0149] Furthermore, in battery cooling priority control, the target evaporator temperature TEO is determined based on the battery cooling priority level. Specifically, if the battery cooling priority level is Low, the target evaporator temperature TEO is determined to be the normal control temperature TEn; if the battery cooling priority level is Mid, the target evaporator temperature TEO is determined to be the first priority temperature TEM; and if the battery cooling priority level is High, the target evaporator temperature TEO is determined to be the second priority temperature TEMh.

[0150] The normal control temperature TEn is the same as the target evaporator temperature TEO during normal control. The first priority temperature TEm is higher than the normal control temperature TEn. The second priority temperature TEh is a predetermined amount higher than the first priority temperature TEm.

[0151] The first priority temperature TEm is determined such that the cooling capacity remains constant even when the airflow rate Va of the fan 32 is increased from the normal control airflow rate Van to the battery cooling priority airflow rate Vam when the battery cooling priority level changes from Low to Mid.

[0152] In other words, when the temperature difference obtained by subtracting the temperature of the indoor evaporator 18 from the intake air temperature of the indoor evaporator 18 is defined as the air temperature difference ΔTe, the cooling capacity Qc is expressed as the product of the air density ρa, the airflow rate Ga of the air flowing through the indoor evaporator 18, and the air temperature difference ΔTe. Therefore, when the airflow rate Va of the blower 32 is increased, the cooling capacity Qc can be kept constant by increasing the target evaporator temperature TEO and lowering the air temperature difference ΔTe.

[0153] The first priority temperature TEm is determined so as not to exceed the permissible upper temperature limit TElimit. The permissible upper temperature limit TElimit is the upper limit of the discharged air temperature from the indoor evaporator 18 that satisfies the occupant's comfort tolerance. In other words, if the discharged air temperature from the indoor evaporator 18 exceeds the permissible upper temperature limit TElimit, the occupant's comfort tolerance will no longer be met.

[0154] Then, in step S220 shown in Figure 3, in order to switch the refrigeration cycle device 10 to the cooling mode refrigerant circuit, the heating expansion valve 14a is fully opened, the dehumidifying on / off valve 15a is closed, and the heating on / off valve 15b is closed. Furthermore, a control signal or control voltage is output to each controlled device so that the control state determined in steps S190 to S220 is obtained.

[0155] In step S230, it is determined whether the battery cooling capacity reaches the target by battery cooling priority control. Specifically, whether the battery cooling capacity reaches the target is determined, for example, based on the first low-temperature side heat transfer medium temperature TWL1 detected by the first low-temperature side heat transfer medium temperature sensor 67a.

[0156] If it is determined in step S230 that the battery cooling capacity will not reach the target even with priority control for battery cooling, the process proceeds to step S240, and the refrigerant circuit is switched to the cooling mode.

[0157] As a result, in the refrigeration cycle device 10 in cooling mode, the refrigerant circulates in the following order: compressor 11, water refrigerant heat exchanger 12, heating expansion valve 14a, outdoor heat exchanger 16, check valve 17, cooling expansion valve 14b, indoor evaporator 18, evaporation pressure regulating valve 20, accumulator 21, and compressor 11. In addition, a vapor compression type refrigeration cycle is configured in which the refrigerant circulates in the following order: compressor 11, water refrigerant heat exchanger 12, heating expansion valve 14a, outdoor heat exchanger 16, check valve 17, cooling expansion valve 14c, chiller 19, accumulator 21, and compressor 11.

[0158] In other words, in the normal control of the cooling mode, a vapor compression type refrigeration cycle is configured in which the water refrigerant heat exchanger 12 and the outdoor heat exchanger 16 function as radiators, and the indoor evaporator 18 and chiller 19 function as evaporators.

[0159] Therefore, the indoor evaporator 18 can cool the air, and the water refrigerant heat exchanger 12 can heat the high-temperature side heat transfer medium. Furthermore, the chiller 19 can cool the low-pressure side heat transfer medium.

[0160] Therefore, in cooling mode, by adjusting the opening of the air mix door 34, a portion of the air cooled by the indoor evaporator 18 is reheated by the heater core 42, and the air, whose temperature is adjusted to approach the target discharge temperature TAO, is blown into the vehicle interior, thereby providing cooling to the vehicle interior.

[0161] Furthermore, the battery 80 can be cooled by flowing the low-temperature heat transfer medium cooled by the chiller 19 into the cooling heat exchange unit 52.

[0162] In the cooling mode, if it is determined in step S170 that the cooling capacity and battery cooling capacity have not reached the target, and in step S180 that there is no room to increase the overall cooling capacity of the refrigeration cycle through normal control, then in step S210, battery cooling priority control is performed to increase the cooling capacity of the battery 80 (in other words, the cooling capacity of the chiller 19).

[0163] The effects of battery cooling priority control are explained using the graph in Figure 7. The graph in Figure 7 shows the characteristics of the cooling capacity Qa and cooling capacity Qc of the entire refrigeration cycle with respect to the temperature of the indoor evaporator 18.

[0164] The thick solid line in Figure 7 shows the characteristics of the overall cooling capacity Qa of the refrigeration cycle when the airflow rate Va of the blower 32 is the normal control airflow rate Van, and the thick dashed line in Figure 7 shows the characteristics of the overall cooling capacity Qa of the refrigeration cycle when the airflow rate Va of the blower 32 is the battery cooling priority airflow rate Vam.

[0165] The thick dashed line in Figure 7 shows the characteristics of the cooling capacity Qc when the airflow rate Va of the blower 32 is the normal control airflow rate Van, and the thick double dotted line in Figure 7 shows the characteristics of the cooling capacity Qc when the airflow rate Va of the blower 32 is the battery cooling priority airflow rate Vam.

[0166] When the control level transitions from normal control or battery cooling priority level = Low to battery cooling priority level = Mid, the airflow rate of the blower 32 increases from the normal control airflow rate Van to the battery cooling priority airflow rate Vam, thereby increasing the overall cooling capacity Qa of the refrigeration cycle.

[0167] In other words, as shown in the graph in Figure 8, the refrigeration cycle device 10 has the characteristic that the cooling capacity Qa of the entire refrigeration cycle increases as the airflow rate Va of the blower 32 increases. This is because an increase in the airflow rate Va of the blower 32 increases the pressure in the indoor evaporator 18, which increases the density of the refrigerant drawn into the compressor 11, thereby increasing the discharge refrigerant flow rate of the compressor 11 and increasing the circulating refrigerant flow rate of the refrigeration cycle 10.

[0168] At this time, the target evaporator temperature TEO is set to the first priority temperature TEm so that even if the airflow rate Va of the blower 32 is increased, the cooling capacity Qc is maintained at a constant capacity Qcn. As a result, the capacity obtained by subtracting the cooling capacity Qc from the total cooling capacity Qa of the refrigeration cycle, i.e., the cooling capacity Qb of the battery 80 (in other words, the cooling capacity of the chiller 19), increases.

[0169] Therefore, as shown in Figure 7, the cooling capacity Qbm of battery 80 when the battery cooling priority level is Mid is higher than the cooling capacity Qbn of battery 80 when the battery cooling priority level is Low.

[0170] In this case, the air discharged from the indoor evaporator 18 becomes hotter and has a higher airflow rate than under normal control, which worsens the cooling feeling. However, by maintaining the cooling capacity Qc at a constant capacity Qcn, the deterioration in the cooling feeling can be kept within an acceptable range.

[0171] Furthermore, when the battery cooling priority level changes from Mid to High, the airflow rate Va of the blower 32 remains unchanged at the battery cooling priority airflow rate Vam, but the target evaporator temperature TEO is determined to be the second priority temperature TEh, which is higher than the first priority temperature TEm, causing the temperature of the indoor evaporator 18 to rise. As a result, the overall cooling capacity Qa of the refrigeration cycle increases further, while the cooling capacity Qc decreases, so the cooling capacity of the battery 80 (in other words, the cooling capacity of the chiller 19) increases further. That is, the cooling capacity Qbh of the battery 80 when the battery cooling priority level is High is even higher than the cooling capacity Qbm of the battery 80 when the battery cooling priority level is Mid.

[0172] In this case, the air blown out from the indoor evaporator 18 becomes even hotter and has a higher airflow, causing the cooling feeling to deteriorate beyond an acceptable range. However, by prioritizing the protection of the battery 80 over the cooling feeling, the cooling capacity of the battery 80 can be ensured as much as possible.

[0173] In this embodiment, as described in steps S170 to S210, the control device 60 performs flow rate increase control, which controls the blower 32 to increase the amount of air supplied to the indoor evaporator 18 when the cooling demand level for the battery 80, i.e., the cooling demand capacity for the chiller 19, increases in the cooling mode.

[0174] According to this, when the cooling requirement level for the battery 80 increases, increasing the airflow rate to the indoor evaporator 18 raises the temperature and pressure of the indoor evaporator 18, which increases the density of the refrigerant drawn in by the compressor 11 and increases the discharge flow rate of the compressor 11. As a result, the flow rate of refrigerant in the chiller 19 increases, which effectively increases the cooling capacity of the chiller 19, i.e., the cooling capacity for the battery 80.

[0175] In this embodiment, as described in step S210, when the control device 60 performs flow rate increase control in the cooling mode, it raises the target temperature TEO of the indoor evaporator 18 so that the cooling capacity of the indoor evaporator 18, i.e., the cooling capacity, is maintained.

[0176] According to this, in flow rate increase control, even if the discharge flow rate of the compressor 11 increases, the cooling capacity of the indoor evaporator 18 does not increase and is maintained, so the cooling capacity for the battery 80 can be increased more effectively.

[0177] In this embodiment, as described in step S210, when the control device 60 is performing flow rate increase control in cooling mode and the cooling capacity for the battery 80 is insufficient, it raises the target temperature TEO of the indoor evaporator 18 so that the cooling capacity on the indoor evaporator 18 side decreases.

[0178] According to this, in flow rate increase control, if the required cooling capacity on the chiller 19 side cannot be secured even if the amount of air supplied to the indoor evaporator 18 is increased, the cooling capacity on the chiller 19 side can be increased by prioritizing the cooling of the chiller 19 side over the cooling of the indoor evaporator 18 side.

[0179] In this embodiment, as described in step S230, if the cooling capacity for the chiller 19 is insufficient even after controlling the flow rate increase in the cooling mode, the control device 60 switches to the cooling mode to stop the cooling of the air in the indoor evaporator 18, i.e., to stop the cooling.

[0180] As a result, in flow rate increase control, if the amount of air supplied to the indoor evaporator 18 is increased and the target temperature TEO of the indoor evaporator 18 is raised, the required cooling capacity on the chiller 19 side can be increased by prioritizing the cooling of the chiller 19 side over the cooling of the indoor evaporator 18 side.

[0181] In this embodiment, as described in steps S180 to S210, when the cooling requirement level for the battery 80 increases in the cooling mode, the control device 60 performs flow rate increase control if it determines that the cooling capacity of the chiller 19 cannot be increased by a predetermined control other than flow rate increase control.

[0182] According to this, even if the cooling capacity of the chiller 19 cannot be increased by a predetermined control, it becomes possible to secure the cooling capacity of the chiller 19 by controlling the flow rate.

[0183] In this embodiment, as described in step S170, the control device 60 determines the cooling requirement level for the battery 80 based on the temperature of the battery 80. This allows the cooling requirement level for the battery 80 to be appropriately determined taking the temperature of the battery 80 into consideration.

[0184] The control device 60 may determine the cooling requirement level for the battery 80 based on a temperature related to the temperature of the battery 80 (for example, the temperature of the low-temperature heat transfer medium that has flowed out from the cooling heat exchange unit 52).

[0185] In this embodiment, as described in step S170, the control device 60 determines the cooling requirement level for the battery 80 based on the cooling load (i.e., air conditioning load) on the indoor evaporator 18 side. This allows the cooling requirement level for the battery 80 to be appropriately determined taking into account the cooling load on the indoor evaporator 18 side.

[0186] (Second Embodiment) As shown in Figure 9, the vehicle air conditioning system 1 of this embodiment includes a cooling evaporator 25, a cooling heat transfer medium circuit 90, and a cooler core 91 instead of the indoor evaporator 18 of the first embodiment. In Figure 9, the same or equivalent parts as in the first embodiment are denoted by the same reference numerals. The same applies to the following drawings.

[0187] The cooling evaporator 25 is a cooling heat exchanger that cools the cooling heat exchanger by exchanging heat between the low-pressure refrigerant, which has been depressurized by the cooling expansion valve 14b, and the cooling heat transfer medium circulating in the cooling heat transfer medium circuit 90, thereby evaporating the low-pressure refrigerant and causing it to exhibit an endothermic effect.

[0188] The cooling evaporator 25 has a refrigerant passage through which low-pressure refrigerant, reduced in pressure by the cooling expansion valve 14b, flows, and a water passage through which cooling heat transfer medium circulates in the cooling heat transfer medium circuit 90. The inlet of the refrigerant passage of the cooling evaporator 25 is connected to the outlet side of the cooling expansion valve 14b, and the outlet of the refrigerant passage of the cooling evaporator 25 is connected to one inlet side of the sixth three-way joint 13f.

[0189] The cooling heat transfer medium circuit 90 is a heat transfer medium circulation circuit that circulates the cooling heat transfer medium. The same fluid as the low-temperature heat transfer medium can be used as the cooling heat transfer medium. The cooling heat transfer medium circuit 90 is equipped with a water passage for the cooling evaporator 25 and a cooling heat transfer medium pump 92.

[0190] The cooling heat transfer fluid pump 92 is a water pump that pressurizes the cooling heat transfer fluid to the inlet side of the water passage of the cooling evaporator 25. The basic configuration of the cooling heat transfer fluid pump 92 is the same as that of the low-temperature side heat transfer fluid pump 51.

[0191] The cooler core 91 is located within the air conditioning case 31 of the indoor air conditioning unit 30, on the downstream side of the airflow from the blower 32 and on the upstream side of the airflow from the heater core 42. The cooler core 91 is a refrigerant heat transfer medium heat exchanger that cools the air by exchanging heat between the cooling heat transfer medium cooled by the cooling evaporator 25 and the air blown from the blower 32.

[0192] The cold air bypass passage 35 inside the air conditioning case 31 directs the air that has passed through the cooler core 91 to bypass the heater core 42. The air mix door 34 inside the air conditioning case 31 adjusts the airflow ratio between the air that passes through the heater core 42 and the air that passes through the cold air bypass passage 35.

[0193] In the first embodiment described above, the flow rate of air flowing through the indoor evaporator 18 is increased in battery cooling priority control, but in this embodiment, the flow rate of the cooling heat transfer medium flowing through the cooling evaporator 25 is increased in battery cooling priority control.

[0194] As a result, the pressure in the cooling evaporator 25 increases, and similar to the battery cooling priority control in the first embodiment described above, the density of the refrigerant drawn into the compressor 11 increases, which increases the discharge refrigerant flow rate of the compressor 11 and increases the circulating refrigerant flow rate of the refrigeration cycle 10. This increases the cooling capacity of the entire refrigeration cycle and the cooling capacity of the battery 80.

[0195] Therefore, similar to the first embodiment described above, when the cooling requirement level for the battery 80 increases in the cooling mode, the cooling capacity for the battery 80 can be effectively increased.

[0196] (Third embodiment) In this embodiment, as shown in Figure 10, the low-temperature heat transfer medium circuit 50 is eliminated compared to the first embodiment. Specifically, in the refrigeration cycle device 10 of this embodiment, the inlet side of the cooling heat exchange unit 52a is connected to the outlet of the cooling expansion valve 14c.

[0197] The cooling heat exchange unit 52a is a so-called direct-cooling type cooler that cools the battery 80 by evaporating the refrigerant flowing through the refrigerant passage and exhibiting an endothermic effect. Therefore, in this embodiment, the cooling unit is composed of the cooling heat exchange unit 52a.

[0198] In the cooling heat exchange section 52a, it is desirable to employ a design that has multiple refrigerant flow paths connected in parallel to each other so that the entire battery 80 can be cooled evenly. The other inlet side of the sixth three-way joint 13f is connected to the outlet of the cooling heat exchange section 52a.

[0199] In this embodiment as well, when the cooling requirement level for the battery 80 increases in the cooling mode, the cooling capacity for the battery 80 can be effectively increased by performing battery cooling priority control similar to that in the first embodiment.

[0200] (Fourth Embodiment) In this embodiment, as shown in Figure 11, the low-temperature side heat transfer medium circuit 50 is eliminated compared to the first embodiment, and a battery evaporator 55, a battery blower 56, and a battery case 57 are added.

[0201] Specifically, the battery evaporator 55 is a cooling heat exchanger that cools the cooling air by exchanging heat between the refrigerant, which has been depressurized by the cooling expansion valve 14c, and the cooling air blown from the battery blower 56, thereby evaporating the refrigerant and causing it to exhibit an endothermic effect. One inlet side of the sixth three-way joint 13f is connected to the refrigerant outlet of the battery evaporator 55.

[0202] The battery blower 56 blows cooling air cooled by the battery evaporator 55 towards the battery 80. The battery blower 56 is an electric blower whose rotation speed (blowing capacity) is controlled by a control voltage output from the control device 60.

[0203] The battery case 57 houses a battery evaporator 55, a battery blower 56, and a battery 80, and also forms an air passage that guides the cooling air blown from the battery blower 56 to the battery 80. This air passage is a circulation passage that guides the cooling air blown onto the battery 80 to the intake side of the battery blower 56.

[0204] Therefore, in this embodiment, the battery 80 is cooled by the battery blower 56 blowing cooling air cooled by the battery evaporator 55 onto the battery 80. In other words, in this embodiment, the cooling unit is composed of the battery evaporator 55, the battery blower 56, and the battery case 57.

[0205] In this embodiment, the control device 60 controls the operation of the battery-powered blower 56 so that it exhibits a predetermined standard blowing capacity for each operating mode, regardless of the operating mode.

[0206] The configuration and operation of the other refrigeration cycle device 10 are the same as in the first embodiment. In this embodiment as well, the same effects as in the first embodiment can be obtained.

[0207] (Fifth embodiment) In this embodiment, as shown in Figure 12, an example is described in which the high-temperature side heat transfer fluid circuit 40 is eliminated and an indoor condenser 12a is adopted, compared to the first embodiment.

[0208] More specifically, the indoor condenser 12a is a heating unit that exchanges heat between the high-temperature, high-pressure refrigerant discharged from the compressor 11 and the blown air, thereby condensing the refrigerant and heating the blown air. The indoor condenser 12a is located inside the air conditioning case 31 of the indoor air conditioning unit 30, similar to the heater core 42 described in the first embodiment.

[0209] The configuration and operation of the other refrigeration cycle device 10 are the same as in the first embodiment. This allows for obtaining the same effects as in the first embodiment.

[0210] (Other embodiments) The refrigeration cycle device 10 is not limited to the embodiments described above and can be modified in various ways as follows. Furthermore, the means disclosed in each of the embodiments may be combined as appropriate to the extent that they are feasible.

[0211] (a) In the embodiments described above, a refrigeration cycle device 10 that can switch between multiple operating modes has been described, but the switching of the operating modes of the refrigeration cycle device 10 is not limited to this.

[0212] For example, in order to perform both air conditioning and battery cooling simultaneously, it is sufficient to be able to perform at least (5) air conditioning mode.

[0213] (b) The components of the refrigeration cycle system are not limited to those disclosed in the embodiments described above. The refrigeration cycle system 10 in the embodiments described above has two evaporators, an air conditioning evaporator (e.g., an indoor evaporator 18) and a battery cooling evaporator (e.g., a chiller 19), but it may have two or more evaporators. For example, it may have three evaporators, a front air conditioning evaporator, a rear air conditioning evaporator and a battery cooling evaporator. The front air conditioning evaporator is an evaporator for cooling the air blown out into the front space of the vehicle interior. The rear air conditioning evaporator is an evaporator for cooling the air blown out into the rear space of the vehicle interior.

[0214] Furthermore, multiple cycle component devices may be integrated. For example, a four-way joint structure may be adopted in which the second three-way joint 13b and the fifth three-way joint 13e are integrated. Also, as the cooling expansion valve 14b and the cooling expansion valve 14c, an electric expansion valve without a fully closed function and an on / off valve may be directly connected.

[0215] Furthermore, although the above-described embodiment explained an example in which R1234yf was used as the refrigerant, the refrigerant is not limited to this. For example, R134a, R152a, R290 (propane), R600a, R410A, R404A, R32, R407C, etc. may be used. Alternatively, a mixed refrigerant, which is a mixture of several of these refrigerants, may be used. Moreover, carbon dioxide may be used as the refrigerant to configure a supercritical refrigeration cycle in which the high-pressure side refrigerant pressure is equal to or greater than the critical pressure of the refrigerant.

[0216] (c) In the embodiments described above, an example was given in which the multiple objects to be cooled are air and the battery 80, but the objects to be cooled are not limited to these. For example, one of the objects to be cooled may be an electrical device that generates heat when in operation, such as an inverter that converts DC current to AC current, a charger that charges power to the battery 80, or a motor generator that outputs driving force for driving by being supplied with power and generates regenerative power when decelerating, etc.

[0217] (e) In each of the embodiments described above, the refrigeration cycle device 10 was applied to the vehicle air conditioning system 1, but the application of the refrigeration cycle device 10 is not limited to this and can be broadly applied to cooling systems that cool multiple objects to be cooled.

[0218] For example, it may be applied to an air conditioning system with a server cooling function that provides air conditioning for a room while appropriately adjusting the temperature of a computer server.

[0219] For example, this could be applied to a refrigerator that appropriately adjusts the temperature of the refrigerator compartment while keeping the temperature of the freezer lower than that of the refrigerator compartment.

[0220] The features of the refrigeration cycle apparatus disclosed herein are as follows: (Item 1) A compressor (11) that inhales, compresses, and discharges refrigerant, A heat sink (12) for dissipating heat from the refrigerant discharged from the compressor, A first pressure reducing unit (14b) reduces the pressure of the refrigerant that has been heated by the heat sink, A first evaporator (18, 25) that causes the refrigerant, which has been depressurized in the first depressurization section, to absorb heat from the heat exchange fluid, thereby evaporating the refrigerant and cooling the heat exchange fluid, A second pressure reduction section (14c) for reducing the pressure of the refrigerant that has been heated by the heat sink, A second evaporator (19) that evaporates the refrigerant, which has been depressurized in the second depressurization section, by allowing it to absorb heat from the object to be cooled (80), thereby evaporating the refrigerant and cooling the object to be cooled, A flow rate adjustment unit (32, 92) adjusts the flow rate of the heat exchange fluid flowing through the first evaporator, A refrigeration cycle apparatus comprising a control unit (60) that performs flow rate increase control by controlling the flow rate adjustment unit to increase the flow rate of the heat exchange fluid when the cooling requirement level for the second evaporator side increases. (Item 2) The control unit, The compressor is controlled so that the temperature (TE) of the first evaporator approaches the target temperature (TEO). The refrigeration cycle apparatus according to item 1, wherein when the flow rate increase control is performed, the target temperature (TEO) is raised so that the cooling capacity of the first evaporator is maintained. (Item 3) The refrigeration cycle apparatus according to item 2, wherein when the control unit is performing the flow rate increase control, if the cooling capacity of the second evaporator is insufficient, the control unit raises the target temperature (TEO) so that the cooling capacity of the first evaporator decreases. (Item 4) The refrigeration cycle apparatus according to item 2 or 3, wherein the control unit stops cooling the heat exchange fluid in the first evaporator if the cooling capacity for the second evaporator is insufficient even after the flow rate increase control is performed. (Item 5) The refrigeration cycle apparatus according to one of items 1 to 4, wherein the control unit determines that the cooling capacity of the second evaporator cannot be increased by a predetermined control other than the flow rate increase control when the cooling requirement level for the object to be cooled increases. (Item 6) The refrigeration cycle apparatus according to any one of items 1 to 5, wherein the control unit determines the cooling requirement level for the object to be cooled based on the temperature of the object to be cooled or a temperature related to the temperature of the object to be cooled. (Item 7) The control unit determines the cooling requirement level for the object to be cooled based on the cooling load on the first evaporator side, according to any one of items 1 to 6 of the refrigeration cycle apparatus. (Item 8) The heat exchange fluid is air that is blown into the space to be air-conditioned. The refrigeration cycle apparatus according to any one of items 1 to 7, wherein the flow rate adjustment unit is a blower (32) that delivers the air. (Item 9) The system includes a cooler core (91) that exchanges heat between the heat exchange fluid and the air supplied to the space to be air-conditioned, The refrigeration cycle apparatus according to any one of items 1 to 7, wherein the flow rate adjustment unit is a pump (92) that delivers the heat exchange fluid. [Explanation of symbols]

[0221] 11 Compressor 12 Water refrigerant heat exchanger (radiator) 14b Expansion valve for cooling (first pressure reducing section) 14c Cooling expansion valve (second pressure reduction section) 18. Indoor evaporator (first evaporator) 19. Chiller (Second Evaporator) 32 Blower (flow rate adjustment part) 60 Control device (control unit) 80 Batteries (to be cooled)

Claims

1. A compressor (11) that inhales, compresses, and discharges a refrigerant, A heat sink (12) for dissipating heat from the refrigerant discharged from the compressor, A first pressure reducing unit (14b) reduces the pressure of the refrigerant that has been heated by the heat sink, A first evaporator (18, 25) that causes the refrigerant, which has been depressurized in the first depressurization section, to absorb heat from the heat exchange fluid to evaporate the refrigerant and cool the heat exchange fluid, A second pressure reducing unit (14c) for reducing the pressure of the refrigerant that has been heated by the heat sink, A second evaporator (19) that evaporates the refrigerant, which has been depressurized in the second depressurization section, by allowing it to absorb heat from the object to be cooled (80), thereby evaporating the refrigerant and cooling the object to be cooled, A flow rate adjustment unit (32, 92) adjusts the flow rate of the heat exchange fluid flowing through the first evaporator, A refrigeration cycle apparatus comprising a control unit (60) that performs flow rate increase control by controlling the flow rate adjustment unit to increase the flow rate of the heat exchange fluid when the cooling requirement level for the second evaporator side increases.

2. The control unit, The compressor is controlled so that the temperature (TE) of the first evaporator approaches the target temperature (TEO). The refrigeration cycle apparatus according to claim 1, wherein when the flow rate increase control is performed, the target temperature (TEO) is raised so as to maintain the cooling capacity of the first evaporator.

3. The refrigeration cycle apparatus according to claim 2, wherein, when the control unit is performing the flow rate increase control, if the cooling capacity of the second evaporator is insufficient, the control unit raises the target temperature (TEO) so that the cooling capacity of the first evaporator decreases.

4. The refrigeration cycle apparatus according to claim 2, wherein the control unit stops cooling the heat exchange fluid in the first evaporator if the cooling capacity to the second evaporator is insufficient even after performing the flow rate increase control.

5. The refrigeration cycle apparatus according to claim 1, wherein the control unit performs the flow rate increase control when it determines that the cooling capacity of the second evaporator cannot be increased by a predetermined control other than the flow rate increase control when the cooling requirement level for the object to be cooled increases.

6. The refrigeration cycle apparatus according to claim 1, wherein the control unit determines the cooling request level for the object to be cooled based on the temperature of the object to be cooled, or a temperature related to the temperature of the object to be cooled.

7. The refrigeration cycle apparatus according to claim 1, wherein the control unit determines the cooling requirement level for the object to be cooled based on the cooling load on the first evaporator side.

8. The heat exchange fluid is air that is blown into the space to be air-conditioned. The refrigeration cycle apparatus according to any one of claims 1 to 7, wherein the flow rate adjustment unit is a blower (32) that delivers the air.

9. The system includes a cooler core (91) that exchanges heat between the heat exchange fluid and the air supplied to the space to be air-conditioned, The refrigeration cycle apparatus according to any one of claims 1 to 7, wherein the flow rate adjustment unit is a pump (92) that delivers the heat exchange fluid.

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