Vehicular air conditioner

Abstract

To provide a vehicular air conditioner which comprises a first heating medium circuit regarding waste heat generated by travelling, and a second heating medium circuit, and can achieve stable air conditioning performance by effectively utilizing the first and the second heating medium circuits.SOLUTION: A vehicular air conditioner 1 comprises: a first heating medium circuit 10; a second heating medium circuit 20; a heat exchanger 13 between heating mediums; and a control device 60. The first heating medium circuit 10 circulates a first heating medium through an engine 11a that is a first heat source 11 generating heat while the vehicle travels. The second heating medium circuit 20 circulates a second heating medium through a refrigeration cycle 30 as a second heat source 21 which can adjust heat quantity to be generated and a heat core 23 which heats blowing air supplied to an air-conditioning object space by heat exchange. The heat exchanger 13 between heating mediums performs heat exchange between the first heating medium circulating in the first heating medium circuit 10 and the second heating medium circulating in the second heating medium circuit 20. The control device 60 controls behavior of the first heating medium circuit 10 and the second heating medium circuit 20.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a vehicle air conditioner that can utilize exhaust heat generated in on-board devices while the vehicle is traveling for heating. [Background technology]

[0002] Conventionally, there is known a technology for heating the vehicle interior in a vehicle air conditioner by utilizing exhaust heat generated in an in-vehicle device while the vehicle is traveling. For example, the technology described in Patent Document 1 discloses a technology related to a vehicle air conditioner that can utilize exhaust heat from an engine mounted in the vehicle to heat the vehicle interior.

[0003] In Patent Document 1, the heat medium that has passed through the engine is caused to flow into a heater core, and the exhaust heat of the engine is used to heat the air to be supplied to the vehicle interior. In addition, in Patent Document 1, the same heat medium is circulated to pass through a radiator that is a component of the refrigeration cycle, thereby realizing heating using the refrigeration cycle. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent Publication No. 2019-104393 Summary of the Invention [Problem to be solved by the invention]

[0005] In the vehicle air conditioner of Patent Document 1, an engine as an on-board device and a radiator as a component device of a refrigeration cycle are arranged in a heating-side heat medium circuit in which a single type of heat medium circulates.

[0006] For this reason, when attempting to use the engine exhaust heat and the heat generated by the refrigeration cycle for heating, it is necessary to circulate the heat medium in the heating-side heat medium circuit through the engine, the components of the refrigeration cycle (i.e., the radiator), and the heater core. In other words, when attempting to use the engine exhaust heat and the heat of the refrigeration cycle for heating, it becomes necessary to switch the circuit configuration of the heating-side heat medium circuit by controlling the operation of a control valve or the like.

[0007] Furthermore, if the circuit configuration of the heating side heat transfer medium circuit is simply switched, the change in circuit configuration will result in an increase or decrease in water flow resistance, which will cause the flow rate of heat transfer medium to the heater core to fluctuate, and it is expected that the heating performance for the passenger compartment will fluctuate.

[0008] In addition, in the configuration of Patent Document 1, the engine and the radiator are arranged in the second heat medium circuit, making it difficult to simultaneously utilize the exhaust heat of the engine and the heat generated by the refrigeration cycle for different purposes.

[0009] In view of the above, an object of the present disclosure is to provide a vehicle air conditioning system that can achieve stable air conditioning performance by effectively utilizing a first heat medium circuit and a second heat medium circuit related to exhaust heat generated during driving. [Means for solving the problem]

[0010] A vehicle air conditioner according to an embodiment of the present disclosure includes a first heat medium circuit (10), a second heat medium circuit (20), a heat medium heat medium heat exchanger (13), and a control unit (60). The first heat medium circuit circulates a first heat medium through a first heat source (11, 11a) that generates heat as the vehicle travels. The second heat medium circuit circulates a second heat medium through a second heat source (21, 30, 42) that is capable of adjusting the amount of heat generated, and a heater core (23) that heats the blown air to be supplied to a space to be air-conditioned by heat exchange. The heat medium heat medium heat exchanger exchanges heat between the first heat medium circulating in the first heat medium circuit and the second heat medium circulating in the second heat medium circuit. The control unit controls the operation of the first heat medium circuit and the second heat medium circuit.

[0011] Therefore, according to the vehicle air conditioner, the first heat medium that recovers the heat generated in the first heat source and the second heat medium that recovers the heat generated in the second heat source can be heat exchanged in the heat medium heat medium heat exchanger. That is, the vehicle air conditioner can appropriately use the heat amounts generated in the first heat source and the second heat source to compensate for excess or deficiency, and can stabilize the amount of heat input to the heater core to stabilize the heating performance.

[0012] In addition, 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 description of the drawings]

[0013] [Figure 1] 1 is a configuration diagram of a vehicle air conditioner according to a first embodiment. [Diagram 2] FIG. 1 is an explanatory diagram showing the configuration of an indoor air conditioning unit according to a first embodiment. [Diagram 3] 1 is a block diagram showing a control system of a vehicle air conditioner according to a first embodiment. [Figure 4] FIG. 4 is an explanatory diagram showing a first circulation mode in a first heat medium circuit. [Diagram 5] FIG. 4 is an explanatory diagram showing a second circulation mode in the first heat medium circuit. [Figure 6] FIG. 4 is an explanatory diagram showing a third circulation mode in the first heat medium circuit. [Figure 7] FIG. 11 is an explanatory diagram showing a fourth circulation mode in the first heat medium circuit. [Figure 8] 5A and 5B are explanatory diagrams showing an example of an initial state and a transition state in a first switching control of the vehicle air conditioner. [Figure 9] 4 is an explanatory diagram showing an example of a switching completion state in a first switching control of the vehicle air conditioner. FIG. [Figure 10] FIG. 4 is an explanatory diagram showing an example of an initial state in second switching control of the vehicle air conditioner. [Figure 11] 6 is an explanatory diagram showing an example of a transition state in a second switching control of the vehicle air conditioner. FIG. [Figure 12]6 is an explanatory diagram showing an example of a switching completion state in a second switching control of the vehicle air conditioner. FIG. [Figure 13] FIG. 6 is a configuration diagram of a vehicle air conditioner according to a second embodiment. [Figure 14] FIG. 11 is a configuration diagram of a vehicle air conditioner according to a third embodiment. [Figure 15] FIG. 11 is a configuration diagram of a vehicle air conditioner according to a fourth embodiment. [Figure 16] FIG. 11 is a configuration diagram of a vehicle air conditioner according to a fifth embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] Hereinafter, a number of embodiments for carrying out the present disclosure will be described with reference to the drawings. In each embodiment, the same reference numerals may be used to designate parts corresponding to matters described in the preceding embodiment, and duplicated descriptions may be omitted. In each embodiment, when only a part of the configuration is described, other embodiments described previously may be applied to the other parts of the configuration. In addition to combinations of parts that are specifically indicated as being possible in each embodiment, it is also possible to partially combine embodiments even if not indicated, as long as there is no particular problem with the combination.

[0015] (First embodiment) A first embodiment of the present disclosure will be described with reference to Fig. 1 to Fig. 12. In the first embodiment, a vehicle air conditioner 1 according to the present disclosure is applied to a hybrid vehicle. A hybrid vehicle is a vehicle that obtains driving force for running the vehicle from an internal combustion engine (i.e., an engine 11a) and a running electric motor.

[0016] The vehicle air conditioner 1 conditions the vehicle cabin, which is the space to be air-conditioned, in a hybrid vehicle. The vehicle air conditioner 1 can switch between a cooling mode, a heating mode, and a dehumidifying and heating mode as air conditioning operation modes for air conditioning the vehicle cabin. The cooling mode is an operation mode in which the blown air to be blown into the vehicle cabin is cooled and blown into the vehicle cabin. The heating mode is an operation mode in which the blown air is heated and blown into the vehicle cabin. The dehumidifying and heating mode is an operation mode in which the cooled and dehumidified blown air is reheated and blown into the vehicle cabin, thereby dehumidifying and heating the vehicle cabin.

[0017] Next, a specific configuration of the vehicle air conditioner 1 according to the first embodiment will be described with reference to Fig. 1 and Fig. 2. As shown in Fig. 1, the vehicle air conditioner 1 according to the first embodiment has a first heat medium circuit 10, a second heat medium circuit 20, and a heat medium heat exchanger 13.

[0018] The first heat medium circuit 10 is a heat medium circuit configured to circulate a first heat medium through a first heat source 11 that generates heat as the hybrid vehicle runs. In the first embodiment, an engine 11a, which is an internal combustion engine that generates driving force for running the hybrid vehicle, is used as the first heat source 11.

[0019] The second heat medium circuit 20 is a heat medium circuit configured to circulate a second heat medium through a second heat source 21 whose heat generation amount can be controlled by control of a control device 60 (to be described later) or the like. As the second heat source 21 in the first embodiment, a refrigeration cycle 30 is adopted.

[0020] The vehicle air conditioner 1 has an interior air conditioning unit 50 and a control device 60. That is, the vehicle air conditioner 1 according to the first embodiment can effectively utilize the heat generated in the first heat source 11 and the heat generated in the second heat source 21 via the heat medium heat medium heat exchanger 13 to adjust the temperature of the blown air supplied from the interior air conditioning unit 50 to the vehicle interior, which is the space to be air-conditioned.

[0021] First, the configuration of the first heat medium circuit 10 in the vehicle air conditioner 1 will be described with reference to Fig. 1. As described above, the first heat medium circuit 10 is a circulation circuit for transferring heat generated in the first heat source 11 via the first heat medium, and has an engine 11a as the first heat source 11, a first heat medium pump 12, and a heat medium heat medium heat exchanger 13.

[0022] The first heat medium in the first heat medium circuit 10 may be a solution containing ethylene glycol, an antifreeze solution, or the like.

[0023] As described above, the first heat source 11 in the vehicle air conditioner 1 is composed of in-vehicle devices mounted on the hybrid vehicle that generate heat incidentally with operation for driving, etc. In the first embodiment, the first heat source 11 is an engine 11a that generates driving force for driving by burning fuel.

[0024] The engine 11a has a water jacket through which a first heat medium flows. The engine 11a is cooled by the first heat medium flowing through the water jacket. Exhaust heat generated by the combustion of fuel in the engine 11a is transferred to the first heat medium flowing through the water jacket. That is, the first heat medium is heated by the exhaust heat of the engine 11a.

[0025] The inlet side of the first heat medium in the engine 11a is connected to the discharge port of the first heat medium pump 12 via a branch section 17 formed in a three-way joint. The first heat medium pump 12 is a heat medium pump that pumps the first heat medium to circulate it in the first heat medium circuit 10. The first heat medium pump 12 is an electric pump whose rotation speed (i.e., pumping capacity) is controlled by a control voltage output from the control device 60. The suction port of the first heat medium pump 12 is connected to the heat medium outlet side of the outside air radiator 14.

[0026] The heat medium heat exchanger 13 is a heat exchanger that exchanges heat between a first heat medium circulating through the first heat medium circuit 10 and a second heat medium circulating through the second heat medium circuit 20. The heat medium heat exchanger 13 has a first heat medium passage 13a through which the first heat medium of the first heat medium circuit 10 flows, and a second heat medium passage 13b through which the second heat medium of the second heat medium circuit 20 flows.

[0027] The heat medium heat exchanger 13 is made of the same metal (aluminum alloy in the first embodiment) having excellent heat conductivity, and each component is integrated by brazing. Therefore, the first heat medium flowing through the first heat medium passage 13a and the second heat medium flowing through the second heat medium passage 13b can exchange heat with each other.

[0028] 1, an outside air radiator 14 and a four-way valve 16 are arranged in the first heat medium circuit 10. The outside air radiator 14 is a radiator that radiates heat contained in the first heat medium circulating in the first heat medium circuit 10 to the outside air.

[0029] The outside air radiator 14 can be arranged at the front side inside the vehicle bonnet, and configured to allow outside air to flow from the front side of the vehicle to the rear side as the hybrid vehicle travels. When the outside air radiator 14 is arranged in this manner, the traveling wind passes through the heat exchange section of the outside air radiator 14, so that heat can be dissipated to the outside air by utilizing the traveling wind. Therefore, the outside air radiator 14 corresponds to an example of an external radiator.

[0030] The four-way valve 16 is a flow rate control valve having four inlet / outlets for the first heat medium. The four-way valve 16 adjusts the flow rate of the first heat medium flowing out of one of the four inlet / outlets with respect to the first heat medium flowing in from the other inlet / outlets.

[0031] One of the inlet / outlets of the four-way valve 16 is connected to one of the inlet / outlets of the branching section 17 in the form of a three-way joint, and the other of the inlet / outlets of the four-way valve 16 is connected to the outlet side of the heat medium passage in the first heat source 11. In addition, the inlet side of the first heat medium passage 13a in the heat medium heat exchanger 13 is connected to another inlet / outlet of the four-way valve 16. Then, the remaining inlet / outlet of the four-way valve 16 is connected to one of the inlet / outlets of the junction section 18 formed in the form of a three-way joint via a bypass flow path 15 described later.

[0032] As described above, the branch section 17 is formed in a three-way joint structure, with one of the three inlet / outlets being an inlet and the remaining two being outlets. As shown in Fig. 1, the inlet of the branch section 17 is connected to the discharge port side of the first heat medium pump 12. One outlet of the branch section 17 is connected to the inlet side of the heat medium passage of the first heat source 11, and the other outlet of the branch section 17 is connected to one of the inlet / outlets of the four-way valve 16.

[0033] The junction 18 is formed in a three-way joint structure like the branching section 17, with one of the three inlet / outlet ports being an outlet port and the remaining two being inlet / outlets. As shown in Fig. 1, the outlet port at the junction is connected to the heat medium inlet side of the outside air radiator 14.

[0034] One of the inlets at the junction 18 is connected to the outlet side of the first heat medium passage 13a in the heat medium heat exchanger 13, and the other inlet at the junction 18 is connected to the remaining inlet / outlet of the four-way valve 16 via the bypass flow path 15.

[0035] As a result, in the first heat medium circuit 10, the first heat medium that has flowed into the four-way valve 16 can bypass the heat medium heat medium heat exchanger 13 and flow into the junction 18 and the outside air radiator 14. That is, the four-way valve 16 can adjust the balance between the flow rate of the first heat medium flowing toward the bypass flow path 15 side and the flow rate of the first heat medium flowing toward the heat medium heat medium heat exchanger 13 side, making it possible to adjust the amount of heat input to the heat medium heat medium heat exchanger 13.

[0036] Therefore, the bypass flow passage 15, the four-way valve 16, the branching section 17, and the junction section 18 correspond to an example of a heat amount adjustment section 45 in the first heat medium circuit 10. In addition, the outside air radiator 14 corresponds to an example of a heat radiating section in the first heat medium circuit 10.

[0037] In the first heat medium circuit 10 configured as above, a plurality of circulation modes of the first heat medium can be realized by controlling the operation of the four-way valve 16. The first to fourth circulation modes realized in the first heat medium circuit 10 will be described in detail later with reference to the drawings.

[0038] Next, the configuration of the second heat medium circuit 20 in the vehicle air conditioner 1 will be described with reference to the drawings. The second heat medium circuit 20 is a heat medium circuit that circulates a second heat medium, and has a second heat medium passage 13b of the heat medium heat exchanger 13, a second heat medium pump 22, a heater core 23, and a refrigeration cycle 30 as the second heat source 21, as shown in FIG.

[0039] The second heat medium circulating through the second heat medium circuit 20 may be a solution containing ethylene glycol, an antifreeze solution, or the like. The second heat medium is configured not to mix with the first heat medium in the first heat medium circuit 10. Therefore, the first heat medium and the second heat medium may be the same type of heat medium, provided that they do not mix with each other.

[0040] The second heat source 21 is a heat source device that heats the second heat medium circulating through the second heat medium circuit 20, and is a heat source whose heat generation amount can be adjusted by the operation control of the control device 60. The outlet side of the heater core 23 is connected to the inlet of the second heat medium for the second heat source 21, and the suction port side of the second heat medium pump 22 is connected to the outlet of the second heat medium in the second heat source 21. A refrigeration cycle 30 is adopted as the second heat source 21 according to the first embodiment. The configuration of the refrigeration cycle 30 will be described in detail later.

[0041] The second heat medium pump 22 is a heat medium pump that pumps the second heat medium to circulate it in the second heat medium circuit 20. The second heat medium pump 22 has a similar configuration to the first heat medium pump 12, and is an electric pump whose rotation speed (i.e., pumping capacity) is controlled by a control voltage output from the control device 60.

[0042] The heater core 23 is a heat exchanger that exchanges heat between the second heat medium heated by the heat medium heat exchanger 13 or the second heat source 21, etc., and the blown air supplied from the interior air conditioning unit 50 into the vehicle cabin, thereby heating the blown air. As shown in Fig. 2, the heater core 23 is disposed in an air conditioning case 51 of the interior air conditioning unit 50. Therefore, the heater core 23 corresponds to an example of a heating heat exchanger.

[0043] As shown in Fig. 1, the second heat medium circuit 20 has a heat medium three-way valve 25 and a heat medium radiator 27. The heat medium three-way valve 25 is configured as an electric three-way flow control valve having three inlet and outlets. The heat medium three-way valve 25 is arranged so that one of the three inlet and outlets is an inlet, and the other two are outlets. That is, the heat medium three-way valve 25 functions as a branching part for the flow of the second heat medium.

[0044] The inlet of the heat medium three-way valve 25 is connected to the outlet side of the second heat medium passage 13b of the heat medium heat exchanger 13. The heat medium inlet side of the heater core 23 is connected to one outlet of the heat medium three-way valve 25, and the inlet side of the heat medium radiator 27 is connected to the other outlet of the heat medium three-way valve 25 via the heat medium bypass flow path 24.

[0045] Therefore, in the second heat medium circuit 20, it is possible to realize a mode in which the second heat medium flowing from the heat medium heat exchanger 13 into the heat medium three-way valve 25 flows into the heater core 23 side and a mode in which the second heat medium flows into the heat medium radiator 27 side. That is, the heat medium three-way valve 25 can adjust the balance between the flow rate of the second heat medium flowing into the heater core 23 side and the flow rate of the second heat medium flowing into the heat medium radiator 27 side, and the amount of heat input to the heat medium heat exchanger 13 can be adjusted.

[0046] The heat medium radiator 27 exchanges heat between the second heat medium heated by the heat medium refrigerant heat exchanger 32 or the like and outside air, and radiates the heat of the second heat medium to the outside air. The heat medium radiator 27 can be disposed on the front side inside the vehicle bonnet. As a result, as the hybrid vehicle travels, the outside air flows from the front side of the vehicle to the rear and passes through the heat exchange section of the heat medium radiator 27, so that the heat of the second heat medium can be radiated to the outside air by using the traveling wind.

[0047] A heat medium junction 26 having a three-way joint structure is connected to the heat medium outlet of the heat medium radiator 27 via a heat medium bypass passage 24. In the heat medium junction 26, one of the three inlet / outlet ports of the three-way joint structure is used as an outlet, and the remaining two are used as inlets.

[0048] 1, the inlet side of the second heat medium passage 13b in the heat medium heat exchanger 13 is connected to the outlet of the heat medium junction 26. The discharge port side of the second heat medium pump 22 is connected to one of the outlets of the heat medium junction 26, and the outlet side of the heat medium radiator 27 is connected to the other of the outlets of the heat medium junction 26 via the heat medium bypass flow path 24. Therefore, the heat medium junction 26 can merge the flow of the second heat medium that has passed through the heat medium radiator 27 and the flow of the second heat medium that has passed through the heater core 23 and the second heat source 21.

[0049] In this way, in the second heat medium circuit 20 of the first embodiment, the heater core 23 and the heat medium radiator 27 are connected in parallel with respect to the flow of the second heat medium passing through the second heat medium passage 13b of the heat medium heat exchanger 13. The heat medium three-way valve 25 can continuously adjust the flow rate ratio of the second heat medium flowing into the heater core 23 side and the second heat medium flowing into the heat medium radiator 27 side in the second heat medium circuit 20.

[0050] In other words, by controlling the operation of the heat medium three-way valve 25, the amount of heat of the second heat medium radiated to the outside air by the heat medium radiator 27 and the amount of heat of the second heat medium radiated to the blown air by the heater core 23 can be adjusted.

[0051] Therefore, the heat medium bypass flow path 24, the heat medium three-way valve 25, and the heat medium junction 26 correspond to an example of a heat amount adjustment section 45 in the second heat medium circuit 20. In addition, the heat medium radiator 27 corresponds to an example of a heat radiating section in the second heat medium circuit 20.

[0052] In the second heat medium circuit 20, the second heat source 21 is disposed upstream of the heat medium heat exchanger 13 with respect to the flow of the second heat medium. When the blown air is heated in the heater core 23, the heat quantity that is insufficient in the second heat source 21 can be compensated for by the heat generated in the first heat source 11 via the heat medium heat exchanger 13. That is, by disposing the second heat source 21 upstream of the heat medium heat exchanger 13, the heat of the first heat source 11 can be efficiently utilized to realize the desired heating capacity.

[0053] Moreover, the heater core 23 is disposed upstream of the second heat source 21 with respect to the flow of the second heat medium. Since the heat of the second heat medium flows into the second heat source 21 after being used to heat the blown air in the heater core 23, the heat exchange efficiency when the second heat medium absorbs heat in the second heat source 21 can be improved.

[0054] 1, the heat medium heat exchanger 13 is arranged upstream of the heat medium three-way valve 25 that functions as a branch point to the heat medium bypass flow path 24 in relation to the flow of the second heat medium in the second heat medium circuit 20. This makes it possible to maximize the amount of heat radiated by the heat medium radiator 27 arranged in the heat medium bypass flow path 24 in the second heat medium circuit 20.

[0055] Next, the refrigeration cycle 30 constituting the second heat source 21 of the vehicle air conditioner 1 will be described with reference to the drawings. The refrigeration cycle 30 is a vapor compression type refrigeration cycle device. As shown in Fig. 1, the refrigeration cycle 30 has a compressor 31, a heat medium refrigerant heat exchanger 32, a first expansion valve 34, a first evaporator 35, a second expansion valve 36, and a second evaporator 37. The refrigeration cycle 30 can pump up heat absorbed by the first evaporator 35 and the second evaporator 37 and heat the second heat medium in the heat medium refrigerant heat exchanger 32.

[0056] The refrigeration cycle 30 of the vehicle air conditioner 1 employs an HFO refrigerant (specifically, HFO1234yf) as the refrigerant, forming a subcritical refrigeration cycle in which the high-pressure side refrigerant pressure does not exceed the critical pressure of the refrigerant. Refrigeration oil for lubricating the compressor 31 is mixed into the refrigerant. PAG oil (polyalkylene glycol oil), which is compatible with liquid-phase refrigerants, is employed as the refrigeration oil. A portion of the refrigeration oil circulates through the cycle together with the refrigerant.

[0057] The compressor 31 draws in, compresses, and discharges the refrigerant in the refrigeration cycle 30. The compressor 31 is disposed inside the vehicle bonnet. The compressor 31 is an electric compressor that uses an electric motor to rotate a fixed-capacity compression mechanism having a fixed discharge capacity. The rotation speed (i.e., refrigerant discharge capacity) of the compressor 31 is controlled by a control signal output from a control device 60, which will be described later.

[0058] The discharge port of the compressor 31 is connected to an inlet side of a refrigerant passage 32b in the heat medium refrigerant heat exchanger 32. The heat medium refrigerant heat exchanger 32 is a heat exchanger that dissipates heat contained in the high-pressure refrigerant discharged from the compressor 31 to a second heat medium circulating through the second heat medium circuit 20, and heats the second heat medium.

[0059] The heat medium refrigerant heat exchanger 32 has a heat medium passage 32a through which the second heat medium of the second heat medium circuit 20 flows, and a refrigerant passage 32b through which the refrigerant of the refrigeration cycle 30 flows. The heat medium refrigerant heat exchanger 32 is formed of the same kind of metal (aluminum alloy in the first embodiment) having excellent thermal conductivity, and each component member is integrated by brazing.

[0060] As a result, the high-pressure refrigerant flowing through the refrigerant passage 32b and the second heat medium flowing through the heat medium passage 32a can exchange heat with each other. The heat medium refrigerant heat exchanger 32 is an example of a condenser that dissipates heat contained in the high-pressure refrigerant.

[0061] A refrigerant branching section 33a having a three-way joint structure is connected to the outlet of the refrigerant passage 32b of the heat medium refrigerant heat exchanger 32. In the refrigerant branching section 33a, one of three inlet / outlets is a refrigerant inlet, and the remaining two are refrigerant outlets. In other words, the refrigerant branching section 33a is a branching section that branches the flow of the liquid-phase refrigerant flowing out from the heat medium refrigerant heat exchanger 32.

[0062] One refrigerant outlet of the refrigerant branch section 33a is connected to the refrigerant inlet side of a first evaporator 35 via a first expansion valve 34. The other refrigerant outlet of the refrigerant branch section is connected to the refrigerant inlet side of a second evaporator 37 via a second expansion valve 36.

[0063] The first expansion valve 34 reduces the pressure of the refrigerant flowing out from one of the refrigerant outlets of the refrigerant branching portion 33a at least during the air conditioning operation mode in which the blown air is cooled. The first expansion valve 34 is an electric variable throttle mechanism, and includes a valve body and an electric actuator. The first expansion valve 34 is a so-called electric expansion valve.

[0064] The valve element of the first expansion valve 34 is configured to be able to change the passage opening degree (in other words, the throttle opening degree) of the refrigerant passage. The electric actuator has a stepping motor that changes the throttle opening degree of the valve element. The operation of the first expansion valve 34 is controlled by a control signal output from the control device 60.

[0065] The first expansion valve 34 is configured as a variable throttle mechanism having a full opening function that fully opens the refrigerant passage when the throttle opening is fully opened, and a full closing function that closes the refrigerant passage when the throttle opening is fully closed. In other words, the first expansion valve 34 can be prevented from exerting a decompression effect on the refrigerant by fully opening the refrigerant passage.

[0066] The first expansion valve 34 can block the inflow of refrigerant to the first evaporator 35 by closing the refrigerant passage. That is, the first expansion valve 34 has both a function as a pressure reducing unit that reduces the pressure of the refrigerant and a function as a refrigerant circuit switching unit that switches the refrigerant circuit. The first expansion valve 34 can also adjust the flow rate of refrigerant flowing into the first evaporator 35 by adjusting the throttle opening of the refrigerant passage.

[0067] The outlet of the first expansion valve 34 is connected to the refrigerant inlet side of the first evaporator 35. As shown in Fig. 2, the first evaporator 35 is disposed in an air conditioning case 51 of the indoor air conditioning unit 50. At least during an air conditioning operation mode in which the blown air is cooled, the first evaporator 35 exchanges heat between the low-pressure refrigerant decompressed by the first expansion valve 34 and the blown air to evaporate the low-pressure refrigerant, thereby cooling the blown air.

[0068] 1, the other refrigerant outlet of the refrigerant branch portion 33a is connected to a second expansion valve 36. The second expansion valve 36 is an electric variable throttle mechanism, similar to the first expansion valve 34, and includes a valve body and an electric actuator. That is, the second expansion valve 36 is a so-called electric expansion valve, and has a fully open function and a fully closed function.

[0069] That is, the second expansion valve 36 can prevent the refrigerant from being depressurized by fully opening the refrigerant passage. Also, the second expansion valve 36 can block the inflow of refrigerant to the second evaporator 37 by closing the refrigerant passage. That is, the second expansion valve 36 has both a function as a depressurizing unit that depressurizes the refrigerant and a function as a refrigerant circuit switching unit that switches the refrigerant circuit. The second expansion valve 36 is an example of a depressurizing unit.

[0070] The outlet of the second expansion valve 36 is connected to the refrigerant inlet side of the second evaporator 37. The second evaporator 37 functions as a heat absorber that absorbs heat into the low-pressure refrigerant decompressed by the second expansion valve 36. The heat absorption target in the second evaporator 37 may be the blown air supplied to the rear seat side of the vehicle compartment, or may be a heat medium of a heat medium circuit different from the first heat medium circuit 10 and the second heat medium circuit 20.

[0071] 1, one refrigerant inlet side of the refrigerant junction 33b is connected to the refrigerant outlet of the first evaporator 35. The other refrigerant inlet side of the refrigerant junction 33b is connected to the refrigerant outlet side of the second evaporator 37. Here, the refrigerant junction 33b has a three-way joint structure similar to the refrigerant branching section 33a, and two of the three inlet and outlets are refrigerant inlets and the remaining one is a refrigerant outlet.

[0072] Therefore, the refrigerant junction 33b is a junction that joins the refrigerant flow out of the first evaporator 35 and the refrigerant flow out of the second evaporator 37. The refrigerant outlet of the refrigerant junction 33b is connected to the suction port side of the compressor 31.

[0073] According to the refrigeration cycle 30 configured in this manner, the amount of heat dissipated in the heat medium refrigerant heat exchanger 32 can be adjusted by controlling the operations of the compressor 31, the first expansion valve 34, and the second expansion valve 36. Therefore, in the vehicle air conditioner 1, the second heat medium can be heated to a desired temperature by utilizing the heat generated in the second heat source 21.

[0074] Next, the interior air conditioning unit 50 constituting the vehicle air conditioner 1 will be described with reference to Fig. 2. The interior air conditioning unit 50 is a unit for blowing out the blown air, the temperature of which has been adjusted by the refrigeration cycle 30, to an appropriate location in the vehicle cabin in the vehicle air conditioner 1. The interior air conditioning unit 50 is disposed inside the instrument panel (i.e., the instrument panel) at the frontmost part of the vehicle cabin.

[0075] The interior air conditioning unit 50 is configured by accommodating an interior blower 52, a first evaporator 35, a heater core 23, etc. in an air passage formed inside an air conditioning case 51 that forms the outer shell of the interior air conditioning unit 50. The air conditioning case 51 forms an air passage for the blown air to be blown into the vehicle cabin. The air conditioning case 51 is molded from a resin (specifically, polypropylene) that has a certain degree of elasticity and excellent strength.

[0076] 2, an inside / outside air switching device 53 is disposed on the most upstream side of the blown air flow of the air conditioning case 51. The inside / outside air switching device 53 switches between introducing inside air (air inside the vehicle cabin) and outside air (air outside the vehicle cabin) into the air conditioning case 51.

[0077] The inside / outside air switching device 53 continuously adjusts the opening area of ​​the inside air inlet for introducing inside air into the air-conditioning case 51 and the outside air inlet for introducing outside air into the air-conditioning case 51 using an inside / outside air switching door, thereby changing the ratio of the amount of inside air introduced to the amount of outside air introduced. The inside / outside air switching door is driven by an electric actuator for the inside / outside air switching door. The operation of this electric actuator is controlled by a control signal output from the control device 60.

[0078] An interior blower 52 is disposed downstream of the inside / outside air switching device 53 in the flow of blown air. The interior blower 52 is configured by an electric blower that drives a centrifugal multi-blade fan with an electric motor. The interior blower 52 blows air drawn in through the inside / outside air switching device 53 toward the vehicle cabin. The rotation speed (i.e., blowing capacity) of the interior blower 52 is controlled by a control voltage output from the control device 60.

[0079] The first evaporator 35 and the heater core 23 are disposed in this order in the flow of the blown air downstream of the interior blower 52. That is, the first evaporator 35 is disposed upstream of the heater core 23 in the flow of the blown air. Therefore, in the interior air-conditioning unit 50 of the vehicle air conditioner 1, at least a part of the blown air that has passed through the first evaporator 35 can be heated by the heater core 23.

[0080] Further, a cold air bypass passage 55 is formed inside the air conditioning case 51. The cold air bypass passage 55 is an air passage that causes the blown air that has passed through the first evaporator 35 to bypass the heater core 23 and flow downstream.

[0081] An air mix door 54 is disposed downstream of the first evaporator 35 and upstream of the heater core 23. The air mix door 54 adjusts the ratio of the amount of air passing through the heater core 23 and the amount of air passing through the cold air bypass passage 55 out of the amount of air passing through the first evaporator 35.

[0082] The air mix door 54 is driven by an electric actuator for driving the air mix door. The operation of this electric actuator is controlled by a control signal output from the control device 60.

[0083] A mixing space is provided downstream of the air flow from the heater core 23. In the mixing space, the air heated by the heater core 23 and the air that has passed through the cold air bypass passage 55 and has not been heated by the heater core 23 are mixed.

[0084] Furthermore, openings for blowing out the blown air (conditioned air) mixed in the mixing space into the vehicle compartment are arranged at the most downstream portion of the blown air flow of the air conditioning case 51. As these openings, a face opening, a foot opening, and a defroster opening (none of which are shown) are provided.

[0085] The face opening is an opening for blowing conditioned air toward the upper body of the occupant in the vehicle cabin, the foot opening is an opening for blowing conditioned air toward the feet of the occupant, and the defroster opening is an opening for blowing conditioned air toward the inside surface of the window glass at the front of the vehicle.

[0086] These face opening holes, foot opening holes, and defroster opening holes are each connected to a face air outlet, a foot air outlet, and a defroster air outlet (none of which are shown) provided in the vehicle cabin via ducts that form air passages.

[0087] Therefore, the temperature of the conditioned air mixed in the mixing space is adjusted by the air mix door 54 adjusting the ratio of the air volume passing through the heater core 23 and the air volume passing through the cold air bypass passage 55. This also adjusts the temperature of the blown air (conditioned air) blown into the vehicle compartment from each air outlet.

[0088] A face door, a foot door, and a defroster door (none of which are shown) are disposed upstream of the face opening hole, the foot opening hole, and the defroster opening hole in the flow of blown air, respectively. The face door adjusts the opening area of ​​the face opening hole. The foot door adjusts the opening area of ​​the foot opening hole. The defroster door adjusts the opening area of ​​the defroster opening hole.

[0089] The face door, foot door, and defroster door constitute a blowing mode switching device that switches the blowing outlet from which the conditioned air is blown out. The face door, foot door, and defroster door are connected to an electric actuator for driving the blowing outlet mode door via a link mechanism or the like, and are rotated in conjunction with each other. The operation of this electric actuator is controlled by a control signal output from the control device 60.

[0090] Next, an overview of the control system of the vehicle air conditioner 1 will be described with reference to Fig. 3. The control device 60 is composed of a well-known microcomputer including a CPU, ROM, RAM, etc., and its peripheral circuits. The control device 60 performs various calculations and processes based on an air conditioning control program stored in the ROM, and controls the operation of various controlled devices connected to the output side. The control device 60 corresponds to an example of a control unit.

[0091] The various controlled devices include the first heat medium pump 12, the four-way valve 16, the second heat medium pump 22, and the heat medium three-way valve 25. Furthermore, the various controlled devices include the compressor 31, the first expansion valve 34, the second expansion valve 36, the indoor blower 52, the inside / outside air switching device 53, the air mix door 54, etc.

[0092] 3, various control sensors are connected to the input side of the control device 60. The control sensors include an inside air temperature sensor 62a, an outside air temperature sensor 62b, and a solar radiation sensor 62c. The control sensors also include a high pressure sensor 62d, a first evaporator temperature sensor 62f, a second evaporator temperature sensor 62g, an air conditioning air temperature sensor 62e, an equipment temperature sensor, and a battery temperature sensor.

[0093] The inside air temperature sensor 62a is an inside air temperature detector that detects the inside air temperature Tr, which is the temperature inside the vehicle cabin. The outside air temperature sensor 62b is an outside air temperature detector that detects the outside air temperature Tam, which is the temperature outside the vehicle cabin. The solar radiation sensor 62c is an solar radiation amount detector that detects the amount of solar radiation As irradiated into the vehicle cabin.

[0094] The high-pressure pressure sensor 62d is a high-pressure pressure detection unit that detects a high-pressure pressure Pd, which is the pressure of the high-pressure refrigerant discharged from the compressor 31. The conditioned air temperature sensor 62e is an air conditioning air temperature detection unit that detects the temperature TAV of air blown from the mixing space into the vehicle cabin.

[0095] The first evaporator temperature sensor 62f is a refrigerant temperature detection unit that detects the refrigerant evaporation temperature in the first evaporator 35. The second evaporator temperature sensor 62g is a refrigerant temperature detection unit that detects the refrigerant evaporation temperature in the second evaporator 37.

[0096] Furthermore, a plurality of heat medium temperature sensors are connected to the input side of the control device 60 in order to detect the temperatures of the heat medium in the first heat medium circuit 10 and the second heat medium circuit 20. The plurality of heat medium temperature sensors include a first heat medium temperature sensor 62h and a second heat medium temperature sensor 62i.

[0097] The first heat medium temperature sensor 62h is disposed at the outlet of the heat medium passage in the engine 11a, and detects the temperature of the first heat medium flowing out from the first heat source 11. The second heat medium temperature sensor 62i is disposed at the outlet of the heat medium passage 32a in the heat medium refrigerant heat exchanger 32, and detects the temperature of the second heat medium flowing out from the heat medium refrigerant heat exchanger 32, which is a component of the second heat source 21.

[0098] The vehicle air conditioner 1 refers to the detection results of the first heat medium temperature sensor 62h and the second heat medium temperature sensor 62i and performs control to realize a heating operation that effectively utilizes the first heat source 11 and the second heat source 21. The details of the control related to this heating operation will be described later with reference to the drawings.

[0099] Furthermore, an operation panel 61 disposed near the instrument panel at the front of the vehicle interior is connected to the input side of the control device 60. Operation signals are input to the control device 60 from various operation switches provided on this operation panel 61.

[0100] The various operation switches provided on the operation panel 61 specifically include an auto switch, an air conditioner switch, an air volume setting switch, a temperature setting switch, etc. The auto switch is an operation switch that sets or cancels the automatic control operation of the refrigeration cycle 30.

[0101] The air conditioner switch is an operational switch for requesting cooling of the blown air by the first evaporator 35. The air volume setting switch is an operational switch that is operated to manually set the air volume of the interior blower 52. The temperature setting switch is an operational switch that sets a target temperature Tset in the vehicle cabin.

[0102] The control device 60 of this embodiment is an integrated unit that controls various control target devices connected to its output side. Therefore, the configuration (i.e., hardware and software) that controls the operation of each control target device constitutes a control unit that controls the operation of each control target device.

[0103] For example, in the control device 60, when a state in which the second heat source 21 is being used for heating is changed to a state in which at least the first heat source 11 is being used for heating, the configuration that performs control to effectively utilize the first heat source 11 and the second heat source 21 to provide stable heating performance corresponds to the first switching control unit 60a.

[0104] Furthermore, within the control device 60, when heating is performed using the second heat source 21 while the first heat source 11 is operating, the configuration that performs control to effectively utilize the first heat source 11 and the second heat source 21 to provide stable heating performance corresponds to the second switching control unit 60b.

[0105] Next, types of circulation modes of the first heat medium in the first heat medium circuit 10 of the vehicle air conditioner 1 will be described with reference to Fig. 4 to Fig. 7. The circulation modes of the first heat medium in the first heat medium circuit 10 of the vehicle air conditioner 1 include a first circulation mode to a fourth circulation mode.

[0106] The first circulation mode of the first heat medium circuit 10 is a circulation mode in which the first heat medium circulates via the first heat source 11, the heat medium heat exchanger 13, and the outdoor air radiator 14. In the first circulation mode of the first heat medium circuit 10, the control device 60 controls the four-way valve 16 to communicate the inlet / outlet on the engine 11a side with the inlet / outlet on the heat medium heat exchanger 13 side, and to close the inlet / outlet on the branching section 17 side and the inlet / outlet on the junction section 18 side. In addition, the control device 60 controls the first heat medium pump 12 to discharge the first heat medium at a predetermined discharge capacity.

[0107] As shown in FIG. 4 , in the first circulation mode of the first heat medium circuit 10, the first heat medium circulates by flowing through the first heat medium pump 12, the engine 11a which is the first heat source 11, the four-way valve 16, the heat medium heat exchanger 13, the junction 18, the outside air radiator 14, and the first heat medium pump 12 in that order.

[0108] Thus, by circulating the first heat medium through the heat medium heat exchanger 13, the heat of the engine 11a, which is the first heat source 11, can be transferred to the second heat medium through the first heat medium. Also, by circulating the first heat medium through the outside air radiator 14, the heat of the engine 11a, which is the first heat source 11, can be radiated to the outside air through the first heat medium.

[0109] The second circulation mode of the first heat medium circuit 10 is a circulation mode in which the first heat medium is circulated via the first heat source 11 and the outside air radiator 14 while bypassing the heat medium heat exchanger 13. In the second circulation mode of the first heat medium circuit 10, the control device 60 controls the four-way valve 16 to communicate the inlet / outlet on the engine 11a side with the inlet / outlet on the junction 18 side, and closes the inlet / outlet on the heat medium heat exchanger 13 side and the inlet / outlet on the branching section 17 side. The control device 60 also controls the first heat medium pump 12 to discharge the first heat medium at a predetermined discharge capacity.

[0110] As shown in FIG. 5 , in the second circulation mode of the first heat medium circuit 10, the first heat medium circulates by flowing through the first heat medium pump 12, the engine 11a which is the first heat source 11, the four-way valve 16, the bypass flow path 15, the junction 18, the outside air radiator 14, and the first heat medium pump 12 in that order.

[0111] As a result, by circulating the first heat medium through the heat medium heat exchanger 13, the heat of the engine 11a, which is the first heat source 11, can be dissipated to the outside air via the first heat medium path without being transferred to the second heat medium via the first heat medium path.

[0112] The third circulation mode of the first heat medium circuit 10 is a circulation mode in which a part of the first heat medium that has passed through the outside air radiator 14 and the first heat source 11 passes through the heat medium heat exchanger 13, and the remaining part circulates while bypassing the heat medium heat exchanger 13. In the third circulation mode of the first heat medium circuit 10, the control device 60 controls the four-way valve 16 to communicate the inlet / outlet on the engine 11a side, the inlet / outlet on the heat medium heat exchanger 13 side, and the inlet / outlet on the junction 18 side, and closes the inlet / outlet on the branching section 17 side. The control device 60 also controls the first heat medium pump 12 to discharge the first heat medium at a predetermined discharge capacity.

[0113] 6, in the third circulation mode of the first heat medium circuit 10, the first heat medium circulates by flowing through the first heat medium pump 12, the engine 11a which is the first heat source 11, the four-way valve 16, the heat medium heat exchanger 13, the junction 18, the outside air radiator 14, and the first heat medium pump 12 in that order. At the same time, the first heat medium circulates by flowing through the first heat medium pump 12, the engine 11a which is the first heat source 11, the four-way valve 16, the bypass flow path 15, the junction 18, the outside air radiator 14, and the first heat medium pump 12 in that order.

[0114] As a result, by circulating a part of the first heat medium through the heat medium heat exchanger 13, a part of the heat of the engine 11a, which is the first heat source 11, can be transferred to the second heat medium through the first heat medium. Also, by circulating the remaining part of the first heat medium so as to bypass the heat medium heat exchanger 13, the amount of heat transferred to the second heat medium through the first heat medium can be adjusted.

[0115] The fourth circulation mode of the first heat medium circuit 10 is a circulation mode in which the first heat medium circulates via the heat medium heat exchanger 13 and the outdoor air radiator 14. In the fourth circulation mode of the first heat medium circuit 10, the control device 60 controls the four-way valve 16 to communicate the inlet / outlet on the branching section 17 side with the inlet / outlet on the heat medium heat exchanger 13 side, and to close the inlet / outlet on the engine 11a side and the inlet / outlet on the junction section 18 side. The control device 60 controls the first heat medium pump 12 to discharge the first heat medium at a predetermined discharge capacity.

[0116] As shown in FIG. 7 , in the fourth circulation mode of the first heat medium circuit 10, the first heat medium circulates by flowing through the first heat medium pump 12, the branching section 17, the four-way valve 16, the heat medium heat exchanger 13, the junction section 18, the outdoor air radiator 14, and the first heat medium pump 12 in this order.

[0117] This allows the outside air radiator 14 to radiate the heat of the first heat medium that has undergone heat exchange with the second heat medium in the heat medium-heat medium heat exchanger 13 to the outside air.

[0118] Next, the first switching control in the vehicle air conditioner 1 will be described with reference to Fig. 8 and Fig. 9. As described above, the first switching control in the vehicle air conditioner 1 is executed when the second heat source 21 is used for heating, and at least the first heat source 11 is used for heating.

[0119] For example, the first switching control applies when switching from a state in which the blown air is heated using heat pumped up by the refrigeration cycle 30 to a state in which the blown air is heated using at least the exhaust heat of the engine 11a. Therefore, the first switching control also applies when switching to a state in which the blown air is heated using both the exhaust heat of the engine 11a and the heat pumped up by the refrigeration cycle 30.

[0120] In the first switching control, a transition state is interposed between an initial state indicating that the second heat source 21 is being used for heating and a switching completion state indicating that at least the first heat source 11 is being used for heating.

[0121] First, an example of an initial state of the first switching control will be described with reference to Fig. 8. As shown in Fig. 8, in the initial state of the first switching control, the first heat medium circuit 10 circulates the first heat medium in the second circulation mode. In the second circulation mode, the first heat medium flowing out of the engine 11a bypasses the heat medium heat medium heat exchanger 13 and circulates through the outside air radiator 14. Therefore, the exhaust heat of the engine 11a is not transferred to the second heat medium in the heat medium heat medium heat exchanger 13, but is radiated to the outside air in the outside air radiator 14.

[0122] In addition, in the initial state of the first switching control, the second heat medium circulates by flowing through the second heat medium pump 22, the heat medium heat medium heat exchanger 13, the heater core 23, the heat medium refrigerant heat exchanger 32, and the second heat medium pump 22 in this order. Here, in the initial state of the first switching control, the refrigeration cycle 30 is operating, and heat absorbed by the first evaporator 35 and the second evaporator 37 is dissipated to the second heat medium by the heat medium refrigerant heat exchanger 32. Therefore, in the initial state of the first switching control, heating of the blown air is realized using the refrigeration cycle 30, which is the second heat source 21, as a heat source.

[0123] Next, the transition state in the first switching control will be described with reference to the drawings. When the condition for heating the blown air using at least the second heat source 21 is satisfied in a state in which the blown air is heated using the first heat source 11, the control device 60 switches the vehicle air conditioner 1 to the transition state.

[0124] In the transition state of the first switching control, the flow of the first heat medium into the heat medium heat exchanger 13 is awaited until the temperature of the first heat medium detected by the first heat medium temperature sensor 62h becomes higher than a predetermined reference value. Specifically, when the temperature of the first heat medium becomes equal to or higher than the temperature of the second heat medium or when the elapsed time since the engine 11a, which is the first heat source 11, was driven becomes equal to or higher than a predetermined value, the control device 60 cancels the transition state and changes it to a switching completion state.

[0125] Next, the switching completion state in the first switching control will be described with reference to Fig. 9. Fig. 9 shows, as an example of the switching completion state of the first switching control, a case in which the blown air is heated using exhaust heat from the engine 11a, which is the first heat source 11, and heat derived from the refrigeration cycle 30, which is the second heat source 21.

[0126] In the first switching control, when the temperature of the first heat medium becomes equal to or higher than the temperature of the second heat medium, in order to change from the transition state to the switching completion state, the control device 60 controls the first heat medium circuit 10 so that the heat medium circulates via at least the engine 11a and the heat medium heat exchanger 13. For example, as shown in Fig. 9, the control device 60 switches the first heat medium circuit 10 from the second circulation mode to the first circulation mode.

[0127] At this time, in the second heat medium circuit, the second heat medium circulates through the heat medium heat medium heat exchanger 13, the heater core 23, and the heat medium refrigerant heat exchanger 32, and the refrigeration cycle 30 is also operating. Therefore, in the switching completed state, the heat of the first heat medium originating from the engine 11a can be transferred to the second heat medium in the heat medium heat medium heat exchanger 13, and the heat originating from the refrigerant of the refrigeration cycle 30 can be transferred to the second heat medium in the heat medium refrigerant heat exchanger 32. Then, the second heat medium heated in the heat medium heat medium heat exchanger 13 and the heat medium refrigerant heat exchanger 32 flows through the heater core 23, so that the vehicle air conditioner 1 in the switching completed state can realize heating using the first heat source 11 and the second heat source 21.

[0128] When the second heat source 21 is used for heating and at least the first heat source 11 is used for heating, if the temperature of the first heat medium is lower than that of the second heat medium, it is assumed that the temperature of the second heat medium will be reduced by heat exchange in the heat medium heat medium heat exchanger 13. In this case, in the heater core 23, the blown air is heated by the heat of the second heat medium, so that the heating performance of the vehicle air conditioner 1 will be reduced when the temperature of the first heat medium is lower than that of the second heat medium.

[0129] Considering this point, in the first switching control of the vehicle air conditioner 1, a transition state is interposed between the initial state and the switching completion state, in which the first heat medium is on standby for flowing into the heat medium heat medium heat exchanger 13 until the temperature of the first heat medium becomes higher than the temperature of the second heat medium. As a result, even if the first heat medium flows into the heat medium heat medium heat exchanger 13, the temperature of the second heat medium does not decrease, so the vehicle air conditioner 1 can effectively utilize the first heat source 11 and the second heat source 21 to exhibit stable heating performance.

[0130] In the transition state of the first switching control, the first heat medium circuit 10 is in the second circulation state in order to wait for the first heat medium to flow into the heat medium heat medium heat exchanger 13, but the present invention is not limited to this. It is sufficient to suppress the first heat medium from flowing into the heat medium heat medium heat exchanger 13, and for example, it is possible to stop the first heat medium pump 12 and stop the circulation of the first heat medium until the temperature of the first heat medium satisfies a predetermined condition.

[0131] Next, the second switching control in the vehicle air conditioner 1 will be described with reference to Fig. 10 to Fig. 12. As described above, the second switching control in the vehicle air conditioner 1 is executed when heating is performed using the second heat source 21 from a state in which the first heat source 11 is operating.

[0132] For example, a case where the state is switched from one in which the engine 11a is running and generating exhaust heat to one in which the heat pumped up by the refrigeration cycle 30 is used to heat the blown air is subject to the second switching control.

[0133] In the second switching control, a transition state is interposed between an initial state indicating that the second heat source 21 is operating and a switching completion state in which the first heat source 11 is used solely for heating.

[0134] First, the initial state of the second switching control will be described with reference to Fig. 10. As shown in Fig. 10, in the initial state of the second switching control, the engine 11a is in a driven state, and the first heat medium circuit 10 is controlled to be in the first circulation mode. In the initial state of the second switching control, the second heat medium is not circulated in the second heat medium circuit 20, and the refrigeration cycle 30 as the second heat source 21 is not operating.

[0135] Therefore, in the initial state of the second switching control, the first heat medium is heated by the exhaust heat of the engine 11a in operation and flows into the heat medium heat medium heat exchanger 13. Since the second heat medium is not circulating in the second heat medium circuit 20, the first heat medium flows toward the outside air radiator 14 without radiating almost any heat to the second heat medium in the heat medium heat medium heat exchanger 13. In the outside air radiator 14, the heat of the first heat medium is radiated to the outside air. That is, in the initial state of the second switching control, the exhaust heat generated by the engine 11a in operation is radiated to the outside air in the outside air radiator 14 via the first heat medium.

[0136] Next, the transition state in the second switching control will be described with reference to Fig. 11. When it is determined that the engine 11a, which is the first heat source 11, is stopped while the engine 11a is running and that the second heat source 21 is used to heat the blown air, the control device 60 changes the vehicle air conditioner 1 to a transition state. A specific example of the transition state related to the second switching control is when a hybrid vehicle transitions from a driving mode in which the vehicle runs using the driving force generated by the engine 11a to a driving mode in which the vehicle runs using the electric motor for driving the vehicle using the power of the battery, and the vehicle interior is heated.

[0137] In the transition state in the second switching control, the control device 60 controls the first heat medium circuit 10 to maintain the first circulation mode, as in the initial state. Here, at the stage of transition to the transition state, the engine 11a, which is the first heat source 11, is stopped. Therefore, in the first heat medium circuit 10 in the transition state, the first heat medium heated by the exhaust heat of the engine 11a is already circulating.

[0138] The control device 60 drives the second heat medium pump 22 for the second heat medium circuit 20, and controls the second heat medium to flow and circulate through the second heat medium pump 22, the heat medium heat medium heat exchanger 13, the heater core 23, the heat medium refrigerant heat exchanger 32, and the second heat medium pump 22 in that order. At this time, the control device 60 operates the refrigeration cycle 30, which is the second heat source 21, and dissipates heat absorbed by the first evaporator 35 and the second evaporator 37 to the second heat medium in the heat medium refrigerant heat exchanger 32.

[0139] That is, in the transition state of the second switching control, in the first heat medium circuit 10, the first heat medium is circulated through the heat medium heat medium heat exchanger 13, and in the second heat medium circuit 20, the second heat medium is circulated through the heat medium heat medium heat exchanger 13 and the heat medium refrigerant heat exchanger 32. Therefore, in the transition state of the second switching control, the second heat medium in the second heat medium circuit 20 is heated in the heat medium refrigerant heat exchanger 32 by the heat pumped up in the refrigeration cycle 30, and in the heat medium heat medium heat exchanger 13, is heated by the first heat medium and the residual heat of the engine 11a.

[0140] The transition state in the second switching control continues until the temperature of the second heat medium detected by the second heat medium temperature sensor 62i becomes higher than a predetermined value. The predetermined value is determined by, for example, the temperature of the first heat medium detected by the first heat medium temperature sensor 62h, and when the temperature of the second heat medium becomes higher than the temperature of the first heat medium, the transition state is changed to the switching completion state.

[0141] In other words, in the transition state of the second switching control, in addition to the refrigeration cycle 30, which is the second heat source 21, the first heat medium and the residual heat of the engine 11a are used in combination, so that the second heat medium can be heated to the same degree as the first heat medium.

[0142] Next, the switching completion state in the second switching control will be described with reference to Fig. 12. In the second switching control, when the temperature of the second heat medium becomes equal to or higher than the temperature of the first heat medium, in order to change from the transition state to the switching completion state, the control device 60 stops driving the first heat medium pump 12 and stops circulation of the first heat medium in the first heat medium circuit 10.

[0143] At this time, in the switching completion state of the second switching control, the refrigeration cycle 30, which is the second heat source 21, is operating, and in the second heat medium circuit 20, the second heat medium circulates through the heat medium heat medium heat exchanger 13, the heater core 23, and the heat medium refrigerant heat exchanger 32. As described above, since the circulation of the first heat medium in the first heat medium circuit 10 is stopped, in the switching completion state, the vehicle air conditioner 1 heats the vehicle cabin using the second heat source 21.

[0144] In the vehicle air conditioner 1, when the refrigeration cycle 30, which is the second heat source 21, stops and the circulation of the second heat medium in the second heat medium circuit 20 also stops, it is assumed that the second heat medium is at a relatively low temperature. Even if the refrigeration cycle 30 is driven in this state to start heating the vehicle interior via the second heat medium, it is assumed that sufficient heating capacity cannot be obtained until the temperature of the second heat medium rises.

[0145] In consideration of this point, in the second switching control of the vehicle air conditioner 1, a transition state is interposed between an initial state in which the first heat source 11 is operating and a switching completion state. In the transition state of the second switching control, the first heat medium and the second heat medium are heat exchanged in the heat medium heat medium heat exchanger 13 until the temperature of the second heat medium becomes higher than the temperature of the first heat medium. That is, in addition to the heat generated in the second heat source 21, the residual heat of the first heat source 11 (i.e., the engine 11a) can be added to the second heat medium via the first heat medium.

[0146] This shortens the time it takes for the temperature of the second heat medium to rise, so that in the vehicle air conditioning system 1, when heating using the second heat source 21 is started, the first heat source 11 and the second heat source 21 can be effectively utilized to provide stable heating performance.

[0147] As described above, the vehicle air conditioner 1 according to the first embodiment includes the first heat medium circuit 10, the second heat medium circuit 20, and the control device 60, as shown in FIG. 1 and other figures. The first heat medium circuit 10 circulates the first heat medium through the engine 11a as the first heat source 11. The second heat medium circuit 20 circulates the second heat medium through the components (heat medium refrigerant heat exchanger 32) of the refrigeration cycle 30 as the second heat source 21 and the heater core 23. The heat medium heat medium heat exchanger 13 is disposed in the first heat medium circuit 10 and the second heat medium circuit 20, and exchanges heat between the first heat medium circulating in the first heat medium circuit 10 and the second heat medium circulating in the second heat medium circuit 20. The control device 60 controls the operation of the first heat medium circuit 10 and the second heat medium circuit 20.

[0148] According to the vehicle air conditioner 1 configured in this manner, the first heat medium that recovers the exhaust heat of the engine 11a and the second heat medium that recovers the heat generated in the refrigeration cycle 30 can be heat exchanged in the heat medium heat medium heat exchanger 13. That is, the vehicle air conditioner 1 can appropriately use the heat amount related to the exhaust heat of the engine 11a and the heat amount generated in the refrigeration cycle 30 to compensate for excess or deficiency, and the heating performance of the vehicle air conditioner 1 can be stabilized.

[0149] The vehicle air conditioner 1 also has a refrigeration cycle 30 as the second heat source 21. The refrigeration cycle 30 has a compressor 31, a heat medium refrigerant heat exchanger 32, a first expansion valve 34 and a second expansion valve 36 as a pressure reducing section, and a first evaporator 35 and a second evaporator 37 as evaporators. The refrigeration cycle 30 can adjust the amount of heat applied to the second heat medium by adjusting the refrigerant discharge capacity of the compressor 31 and the amount of refrigerant pressure reduction in the pressure reducing section.

[0150] Therefore, according to the vehicle air conditioning system 1, by adopting the refrigeration cycle 30 as the second heat source 21, it becomes possible to efficiently heat the second heat medium, thereby improving the heating performance and power saving of the vehicle air conditioning system 1.

[0151] As shown in FIG. 1, the vehicle air conditioning device 1 has a heat quantity adjustment unit 45 that adjusts the amount of heat input to the heat medium heat exchanger 13, and a heat dissipation unit 46 that dissipates the amount of heat that was not input to the heat medium heat exchanger 13 by the heat quantity adjustment unit 45.

[0152] This allows the vehicle air conditioner 1 to balance the heat generated by the first heat source 11 and the heat generated by the second heat source 21 with the amount of heat required by the heater core 23. For example, when the heat generated by the first heat source 11 and the second heat source 21 is in excess of the amount of heat required by the heater core 23, the vehicle air conditioner 1 controls the heat amount adjustment unit 45 to dissipate the excess amount of heat from the heat dissipation unit 46 and input an appropriate amount of heat to the heater core 23.

[0153] As shown in FIG. 1, in the first heat medium circuit 10 of the vehicle air conditioner 1, a bypass flow path 15 and a four-way valve 16 are arranged as a heat amount adjustment section 45, and an outside air radiator 14 is arranged as a heat radiating section 46.

[0154] 4 to 7, the vehicle air conditioner 1 can adjust the amount of heat input to the heat medium heat exchanger 13 and the amount of heat radiated to the outside air by the outside air radiator 14 by controlling the operation of the four-way valve 16. Since the amount of heat input to the heat medium heat exchanger 13 shows a strong correlation with the amount of heat input to the heater core 23 via the second heat medium, the amount of heat input to the heater core 23 can be appropriately adjusted by controlling the operation of the four-way valve 16.

[0155] In addition, in the second heat medium circuit 20 of the vehicle air conditioner 1, a heat medium bypass flow path 24 and a heat medium three-way valve 25 are arranged as a heat amount adjustment section 45, and a heat medium radiator 27 is arranged as a heat radiating section 46.

[0156] Therefore, by controlling the operation of the heat medium three-way valve 25, the vehicle air conditioner 1 can adjust the flow rate of the second heat medium flowing into the heater core 23 and the flow rate of the second heat medium flowing toward the heat medium bypass passage 24 and the heat medium radiator 27. As a result, by controlling the operation of the heat medium three-way valve 25, the vehicle air conditioner 1 can appropriately adjust the amount of heat input to the heater core 23.

[0157] 4 and 5, the vehicle air conditioner 1 can switch between a first circulation mode and a second circulation mode as the circulation mode of the first heat medium in the first heat medium circuit 10. The first circulation mode is a mode in which the first heat medium circulates via the outside air radiator 14, the engine 11a, and the heat medium heat medium heat exchanger 13, and the second circulation mode is a mode in which the first heat medium circulates via the engine 11a and the outside air radiator 14 without passing through the heat medium heat medium heat exchanger 13.

[0158] Therefore, the vehicle air conditioner 1 can select the destination of the exhaust heat of the engine 11a, which is the first heat source 11, from the heat medium heat medium heat exchanger 13 and the outside air radiator 14 by selectively using the first circulation mode and the second circulation mode as the circulation mode of the first heat medium in the first heat medium circuit 10. This allows the vehicle air conditioner 1 to control the amount of heat exchange between the first heat medium and the second heat medium in the heat medium heat medium heat exchanger 13. In other words, the vehicle air conditioner 1 can stabilize the heating performance of the heater core 23 by effectively utilizing the heat amount originating from the first heat source 11 in the first heat medium and the heat amount originating from the second heat source 21 in the second heat medium.

[0159] 6, the vehicle air conditioner 1 can switch the circulation mode of the first heat medium in the first heat medium circuit 10 to a third circulation mode in addition to the first and second circulation modes. The third circulation mode is a mode in which a part of the first heat medium that has passed through the outside air radiator 14 and the engine 11a passes through the heat medium heat medium heat exchanger 13, and at the same time, the remaining first heat medium circulates bypassing the heat medium heat medium heat exchanger 13.

[0160] As a result, the vehicle air conditioner 1 employs the third circulation mode as the circulation mode of the first heat medium in the first heat medium circuit 10, so that a part of the exhaust heat of the engine 11a can be dissipated to the second heat medium and the remaining amount of heat can be dissipated to the outside air. That is, the vehicle air conditioner 1 can accurately adjust the distribution of the amount of heat originating from the first heat source 11 in the first heat medium and the amount of heat originating from the second heat source 21 in the second heat medium, thereby stabilizing the heating performance of the heater core 23.

[0161] 7, the vehicle air conditioner 1 can switch the circulation mode of the first heat medium in the first heat medium circuit 10 to a fourth circulation mode in addition to the first to third circulation modes. The fourth circulation mode is a mode in which the first heat medium circulates via the heat medium heat exchanger 13 and the outside air radiator 14 without passing through the engine 11a.

[0162] As a result, by switching to the fourth circulation mode, the vehicle air conditioner 1 can dissipate heat of the first heat medium that has exchanged heat with the second heat medium in the heat medium heat medium heat exchanger 13 to the outside air. The vehicle air conditioner 1 can switch the circulation mode of the first heat medium in the first heat medium circuit 10 to various circulation modes, and can effectively utilize the heat amount derived from the first heat source 11 and the heat amount derived from the second heat source 21 to stabilize the heating performance.

[0163] 1, in the second heat medium circuit 20 of the vehicle air conditioner 1, the heat medium refrigerant heat exchanger 32 is disposed upstream of the heat medium heat medium heat exchanger 13 with respect to the flow of the second heat medium. The heat medium refrigerant heat exchanger 32 is one of the components of the refrigeration cycle 30 which is the second heat source 21, and is a radiator which radiates heat pumped up by the refrigeration cycle 30 to the second heat medium.

[0164] In the second heat medium circuit 20, by arranging the heat medium refrigerant heat exchanger 32 upstream of the heat medium heat medium heat exchanger 13, it is possible to specify the amount of heat to be dissipated from the first heat medium to the second heat medium in the heat medium heat exchanger 13. As a result, the vehicle air conditioner 1 can compensate for the shortage of heat relative to the desired heating performance with heat derived from the first heat source 11, and can efficiently stabilize the heating performance.

[0165] In the second heat medium circuit 20 of the vehicle air conditioner 1, the heater core 23 is disposed upstream of the heat medium refrigerant heat exchanger 32 with respect to the flow of the second heat medium. As described above, the heat medium refrigerant heat exchanger 32 is one of the components of the refrigeration cycle 30, which is the second heat source 21, and is a radiator that radiates heat pumped up by the refrigeration cycle 30 to the second heat medium.

[0166] Therefore, the second heat medium in the second heat medium circuit 20 flows into the heat medium-refrigerant heat exchanger 32 constituting the second heat source 21 in a state in which the second heat medium has dissipated heat to the heater core 23 to heat the blown air. That is, since the second heat medium can be supplied to the second heat source 21 in a state in which the second heat medium exhibits the lowest possible temperature, the amount of heat generated in the second heat source 21 can be efficiently recovered.

[0167] In addition, when the refrigeration cycle 30 is used as the second heat source 21, if the amount of heat radiation in the heat medium refrigerant heat exchanger 32 cannot be ensured, it is assumed that a high-pressure abnormality will occur in the refrigerant pressure of the refrigeration cycle 30. In this regard, since the second heat medium can be circulated through the heat medium refrigerant heat exchanger 32 at the lowest possible temperature, the vehicle air conditioner 1 can suppress the occurrence of a high-pressure abnormality in the refrigeration cycle.

[0168] In the second heat medium circuit 20 of the vehicle air conditioner 1, the heat medium heat exchanger 13 is arranged upstream of the heat medium three-way valve 25 which functions as a branch point to the heat medium bypass flow path 24 with respect to the flow of the second heat medium.

[0169] This allows the second heat medium that has exchanged heat with the first heat medium in the heat medium heat exchanger 13 to flow through the heat medium bypass flow path 24 and the heat medium radiator 27 while maintaining as much heat as possible. That is, the vehicle air conditioner 1 can maximize the amount of heat radiated from the second heat medium in the heat medium radiator 27. For example, in a case where frost forms on the heat medium radiator 27 in an environment where the outside air is low temperature and high humidity, by adopting this configuration, it is possible to improve the defrosting performance when defrosting the heat medium radiator 27 with the second heat medium.

[0170] In addition, in the vehicle air conditioner 1, the first switching control is executed when at least the first heat source 11 is used for heating from a state in which the second heat source 21 is used for heating. As shown in Fig. 8 and Fig. 9, in the first switching control, a transition state is interposed between an initial state indicating a state in which the second heat source 21 is used for heating and a switching completion state in which at least the first heat source 11 is used for heating.

[0171] In the transition state of the first switching control, the refrigeration cycle 30, which is the second heat source 21, is operated until the temperature of the first heat medium becomes equal to or higher than the temperature of the second heat medium, and the second heat medium is maintained in the second heat medium circuit 20 circulating at least through the second heat source 21 and the heater core 23. At this time, the first heat medium circuit 10 circulates the first heat medium in the second circulation mode, and waits for the first heat medium that has circulated through the first heat source 11 to flow into the heat medium heat medium heat exchanger 13. By transitioning to the switching completion state shown in FIG. 9 through this transition state, heating can be performed using at least the first heat source 11 with the temperature of the first heat medium sufficiently increased.

[0172] Here, when the second heat source 21 is used for heating and at least the first heat source 11 is used for heating, if the temperature of the first heat medium is lower than that of the second heat medium, it is assumed that the temperature of the second heat medium will be reduced by heat exchange in the heat medium heat medium heat exchanger 13. In this case, in the heater core 23, the blown air is heated by the heat of the second heat medium, so that in a state where the temperature of the first heat medium is lower than that of the second heat medium, the heating performance of the vehicle air conditioner 1 will be reduced.

[0173] In this regard, in the first switching control of the vehicle air conditioner 1, a transition state is interposed between the initial state and the switching completion state, so that the temperature of the second heat medium does not decrease even if the first heat medium flows into the heat medium heat medium heat exchanger 13. Therefore, by performing the first switching control, the vehicle air conditioner 1 can effectively utilize the first heat source 11 and the second heat source 21 to exhibit stable heating performance.

[0174] In the vehicle air conditioner 1, the second switching control is executed when the vehicle changes from a state in which the first heat source 11 is operating to a state in which heating is performed using the second heat source 21. As shown in Fig. 10 to Fig. 12, in the second switching control, a transition state is interposed between an initial state in which the second heat source 21 is operating and a switching completion state in which the first heat source 11 is used solely for heating.

[0175] In the transition state of the second switching control, the first heat medium is circulated through the heat medium heat medium heat exchanger 13 in the first heat medium circuit 10, and the second heat medium is circulated through the heat medium heat medium heat exchanger 13 and the heat medium refrigerant heat exchanger 32 in the second heat medium circuit 20. Therefore, in the transition state of the second switching control, the second heat medium in the second heat medium circuit 20 is heated in the heat medium refrigerant heat exchanger 32 by the heat pumped up in the refrigeration cycle 30, and is heated in the heat medium heat medium heat exchanger 13 by the first heat medium and the residual heat of the engine 11a. The transition state of the second switching control continues until the temperature of the second heat medium detected by the second heat medium temperature sensor 62i becomes higher than a predetermined value.

[0176] Here, in the vehicle air conditioner 1, when the refrigeration cycle 30, which is the second heat source 21, stops and the circulation of the second heat medium in the second heat medium circuit 20 also stops, it is assumed that the second heat medium is at a relatively low temperature. Even if the refrigeration cycle 30 is driven from this state to start heating the vehicle interior via the second heat medium, it is assumed that sufficient heating capacity cannot be obtained until the temperature of the second heat medium rises.

[0177] In this regard, in the second switching control of the vehicle air conditioner 1, by interposing a transition state between the initial state and the switching completion state, the residual heat of the first heat source 11 (i.e., the engine 11a) can be added to the second heat medium via the first heat medium in addition to the heat generated in the second heat source 21. This can shorten the period until the temperature of the second heat medium rises, so that the vehicle air conditioner 1 can effectively utilize the first heat source 11 and the second heat source 21 to exhibit stable heating performance when heating using the second heat source 21 is started.

[0178] Second embodiment Next, a second embodiment different from the above-described embodiment will be described with reference to Fig. 13. In the vehicle air conditioner 1 according to the second embodiment, the configuration of the second heat medium circuit 20 is different from that of the above-described first embodiment. The other configurations (the first heat medium circuit 10, the refrigeration cycle 30, the interior air conditioning unit 50, the control device 60, etc.) in the vehicle air conditioner 1 according to the second embodiment are the same as those in the above-described first embodiment, so repeated description will be omitted.

[0179] As shown in Fig. 13, the second heat medium circuit 20 of the vehicle air conditioner 1 according to the second embodiment has a second heat medium pump 22, a heat medium heat medium heat exchanger 13, a heater core 23, and a heat medium refrigerant heat exchanger 32 which is a component of the second heat source 21. In other words, the second heat medium circuit 20 according to the second embodiment is different from the first embodiment in that it does not have a heat medium bypass flow path 24, a heat medium three-way valve 25, a heat medium junction 26, or a heat medium radiator 27. Therefore, in the second heat medium circuit 20 according to the second embodiment, the second heat medium flowing out of the heat medium heat medium heat exchanger 13 flows entirely into the heater core 23.

[0180] With the exception of the heat amount adjustment section 45 and the heat radiating section 46 in the second heat medium circuit 20, the vehicle air conditioner 1 according to the second embodiment can achieve the same effects as those of the first embodiment described above.

[0181] In the second embodiment, the first heat medium circuit 10 has a bypass flow path 15 and a four-way valve 16 as a heat amount adjustment section 45, and has an outside air radiator 14 as a heat dissipation section 46. Therefore, by using the heat amount adjustment section 45 and the heat dissipation section 46 of the first heat medium circuit 10, the amount of heat input to the heat medium heat exchanger 13 can be adjusted, and the function of adjusting the heating performance of the vehicle air conditioner 1 is also ensured.

[0182] As described above, according to the vehicle air conditioner 1 of the second embodiment, even if the configuration of the second heat medium circuit 20 is changed, it is possible to obtain the same advantageous effects as those of the above-mentioned embodiment due to the configuration and operation.

[0183] Third embodiment Next, a third embodiment different from the above-described embodiments will be described with reference to Fig. 14. In the vehicle air conditioner 1 according to the third embodiment, the configuration of the first heat medium circuit 10 is different from that of the above-described first embodiment. The other configurations of the vehicle air conditioner 1 according to the third embodiment (the second heat medium circuit 20, the refrigeration cycle 30, the interior air conditioning unit 50, the control device 60, etc.) are the same as those of the above-described first embodiment, so repeated description will be omitted.

[0184] As shown in Fig. 14, the first heat medium circuit 10 of the vehicle air conditioner 1 according to the third embodiment has an engine 11a as a first heat source 11, a first heat medium pump 12, a heat medium heat medium heat exchanger 13, and an outside air radiator 14. In other words, the first heat medium circuit 10 according to the third embodiment is different from the first embodiment in that it does not have a bypass flow path 15, a four-way valve 16, a branching section 17, or a merging section 18. Therefore, in the first heat medium circuit 10 of the third embodiment, all of the first heat medium flowing out from the first heat source 11 flows into the heat medium heat medium heat exchanger 13.

[0185] With the exception of the heat amount adjustment section 45 and the heat radiating section 46 in the first heat medium circuit 10, the vehicle air conditioner 1 according to the third embodiment can achieve the same effects as those of the first embodiment described above.

[0186] In the third embodiment, the second heat medium circuit 20 has a heat medium bypass flow path 24 and a heat medium three-way valve 25 as a heat amount adjustment section 45, and has a heat medium radiator 27 as a heat radiating section 46. Therefore, by using the heat amount adjustment section 45 and the heat radiating section 46 of the second heat medium circuit 20, the amount of heat input to the heat medium heat exchanger 13 can be adjusted, and the function of adjusting the heating performance of the vehicle air conditioner 1 is also ensured.

[0187] As described above, according to the vehicle air conditioner 1 of the third embodiment, even if the configuration of the first heat medium circuit 10 is changed, it is possible to obtain the same advantageous effects as those of the above-mentioned embodiment due to the configuration and operation.

[0188] (Fourth embodiment) Next, a fourth embodiment different from the above-described embodiments will be described with reference to Fig. 15. The vehicle air conditioner 1 according to the fourth embodiment differs from the first embodiment in the configurations of the first heat medium circuit 10, the second heat medium circuit 20, and the refrigeration cycle 30. The other configurations (indoor air conditioning unit 50, indoor air conditioning unit 50) in the vehicle air conditioner 1 according to the fourth embodiment are the same as those in the first embodiment, so repeated description will be omitted.

[0189] 15, the first heat medium circuit 10 of the vehicle air conditioner 1 according to the fourth embodiment has an engine 11a as a first heat source 11, a first heat medium pump 12, a heat medium heat exchanger 13, and an outside air radiator 14. In other words, the first heat medium circuit 10 according to the fourth embodiment does not have components corresponding to the heat amount adjustment section 45 and the heat radiating section 46, and has the same configuration as the first heat medium circuit 10 according to the third embodiment.

[0190] The second heat medium circuit 20 of the vehicle air conditioner 1 according to the fourth embodiment has a second heat medium pump 22, a heat medium heat medium heat exchanger 13, a heater core 23, and a heat medium refrigerant heat exchanger 32 which is a component of the second heat source 21. In other words, the second heat medium circuit 20 according to the second embodiment does not have components corresponding to the heat amount adjustment section 45 and the heat dissipation section 46, and has the same configuration as the second heat medium circuit 20 according to the second embodiment.

[0191] In the vehicle air conditioner 1 according to the fourth embodiment, a refrigeration cycle 30 is arranged as the second heat source 21. As in the above-described embodiments, the refrigeration cycle 30 according to the fourth embodiment has a compressor 31, a heat medium refrigerant heat exchanger 32, a first expansion valve 34, a first evaporator 35, a second expansion valve 36, and a second evaporator 37. The refrigeration cycle 30 according to the fourth embodiment further has components corresponding to a heat amount adjustment section 45 and a heat radiating section 46.

[0192] As shown in Fig. 15, in a refrigeration cycle 30 according to the fourth embodiment, a three-way refrigerant valve 39 is disposed between a discharge port of the compressor 31 and a refrigerant inlet in a refrigerant passage 32b of a heat medium refrigerant heat exchanger 32. The three-way refrigerant valve 39 is an electric three-way flow control valve having three inlet and outlet ports, and is disposed so that one of the three inlet and outlet ports serves as an inlet port and the other two serve as outlet ports. The three-way refrigerant valve 39 functions as a branching portion for the flow of the refrigerant discharged from the compressor 31.

[0193] The inlet of the refrigerant three-way valve 39 is connected to the discharge port side of the compressor 31. In addition, one of the outlets of the refrigerant three-way valve 39 is connected to the refrigerant inlet side of the refrigerant passage 32b of the heat medium refrigerant heat exchanger 32, and the other of the outlets of the refrigerant three-way valve 39 is connected to a refrigerant radiator 41 via a refrigerant bypass passage 38.

[0194] The refrigerant radiator 41 exchanges heat between the high-pressure refrigerant discharged from the compressor 31 and outside air, and radiates heat from the high-pressure refrigerant to the outside air. A refrigerant connection part 40 having a three-way joint structure is connected to the refrigerant outlet side of the refrigerant radiator 41 via the refrigerant bypass flow path 38. The refrigerant connection part 40 uses one of the three inlet / outlet ports of the three-way joint structure as an outlet port, and the remaining two as inlets.

[0195] As described above, one of the inlets of the refrigerant connection part 40 is connected to the outlet side of the refrigerant radiator 41 via the refrigerant bypass passage 38, and the other of the inlets of the refrigerant connection part 40 is connected to the outlet side of the refrigerant passage 32b of the heat medium refrigerant heat exchanger 32. The inlet side of the refrigerant branch part 33a is connected to the outlet of the refrigerant connection part 40.

[0196] In the refrigeration cycle 30 according to the fourth embodiment configured as described above, the operation of the refrigerant three-way valve 39 is controlled to allow the high-pressure refrigerant discharged from the compressor 31 to bypass the heat medium refrigerant heat exchanger 32 via the refrigerant bypass passage 38. That is, in the refrigeration cycle 30 according to the fourth embodiment, the amount of heat originating from the high-pressure refrigerant flowing into the heat medium refrigerant heat exchanger 32 can be adjusted, and the amount of heat dissipated to the second heat medium can be adjusted. As described above, in the heater core 23, the blown air is heated by the heat possessed by the second heat medium, so that the vehicle air conditioner 1 according to the fourth embodiment can adjust the heating performance.

[0197] In the refrigeration cycle 30 according to the fourth embodiment, the refrigerant bypass passage 38, the refrigerant three-way valve 39, and the refrigerant connection section 40 correspond to an example of a heat adjustment section 45, and the refrigerant radiator 41 corresponds to an example of a heat radiating section 46.

[0198] With the exception of matters relating to the heat amount adjustment section 45 and the heat radiating section 46 in the refrigeration cycle 30, the vehicle air conditioner 1 according to the fourth embodiment can achieve the same effects as those of the first embodiment described above.

[0199] As described above, according to the vehicle air conditioning device 1 of the fourth embodiment, even if the configuration of the refrigeration cycle 30 as the second heat source 21 is changed, the same functional effects as those of the above-mentioned embodiment can be obtained from the common configuration and operation.

[0200] Fifth embodiment Next, a fifth embodiment different from the above-described embodiments will be described with reference to Fig. 16. In the vehicle air conditioner 1 according to the fifth embodiment, the configuration adopted as the second heat source 21 is different from that of the above-described embodiments. The other configurations (first heat medium circuit 10, second heat medium circuit 20, interior air conditioning unit 50, control device 60) in the vehicle air conditioner 1 according to the fifth embodiment are the same as those in the above-described embodiments, and therefore will not be described again.

[0201] 16, in the vehicle air conditioner 1 according to the fifth embodiment, an electric heater 42 is arranged as the second heat source 21 in the second heat medium circuit 20. The electric heater 42 according to the fifth embodiment is arranged between the outlet of the heater core 23 in the second heat medium circuit 20 and the suction port side of the second heat medium pump 22.

[0202] The electric heater 42 generates heat when power is supplied, and heats the second heat medium flowing through the heat medium passage of the electric heater 42. For example, a PTC heater having a PTC element (i.e., a positive temperature coefficient thermistor) can be used as the electric heater 42. The electric heater 42 can arbitrarily adjust the amount of heat for heating the second heat medium by a control voltage output from the control device 60, and corresponds to an example of the second heat source 21.

[0203] Therefore, according to the vehicle air conditioning device 1 of the fifth embodiment, even if an electric heater 42 is adopted as the second heat source 21 instead of the refrigeration cycle 30, the exhaust heat of the engine 11a and the heat generated by the electric heater 42 can be efficiently utilized to provide stable heating performance.

[0204] As described above, according to the vehicle air conditioning device 1 of the fifth embodiment, even when an electric heater 42 is adopted as the second heat source 21 instead of the refrigeration cycle 30, it is possible to obtain the same advantageous effects as those of the above-mentioned embodiment due to the configuration and operation. (Other embodiments) The present disclosure is not limited to the above-described embodiment, and various modifications can be made as follows without departing from the spirit and scope of the present disclosure.

[0205] (a) In the above-described embodiment, the engine 11a that generates heat incidentally with the combustion of fuel for driving or the like is used as the first heat source 11, but the present invention is not limited to this embodiment. As the first heat source 11, various on-board devices can be used as long as they are devices that generate heat incidentally with the operation for driving or the like, among the on-board devices installed in the vehicle.

[0206] For example, an in-vehicle battery, an inverter INV, a motor generator MG, a transaxle device, a PCU, a control device for ADAS, or the like may be adopted as the first heat source 11. For example, a traveling motor can be used as the first heat source 11 because it generates heat when a driving force for traveling is generated by energizing the traveling motor. Also, an in-vehicle battery can be used as the first heat source 11 because power is input and output as the vehicle travels and heat is generated in response to the input and output.

[0207] The inverter INV is a power conversion unit that converts DC current into AC current. The motor generator MG is supplied with power to output driving force for running, and also generates regenerative power during deceleration, etc.

[0208] The transaxle device is a device that integrates a transmission with a final gear and a differential gear (diff gear). The PCU is a power control unit that performs power transformation and power distribution. The control device for ADAS is a control device for an advanced driver assistance system. These components, like the engine 11a, generate heat incidentally in conjunction with operation for the purpose of running the vehicle, and can therefore be used as the first heat source 11.

[0209] (b) In the above embodiment, the refrigeration cycle 30 or the electric heater 42 is used as the second heat source 21, but the present invention is not limited to this. As the second heat source 21, various configurations can be used as long as the amount of heat used to heat the second heat medium can be adjusted by the control of the control device 60, and for example, a Peltier element or the like may be used.

[0210] (c) The circuit configurations of the first heat medium circuit 10, the second heat medium circuit 20, and the refrigeration cycle 30 in the above-described embodiment are only examples, and the configurations of the first heat medium circuit 10, the second heat medium circuit 20, and the refrigeration cycle 30 can be changed as appropriate.

[0211] The first heat medium circuit 10 can be appropriately connected to each of the components as long as it is configured to circulate the first heat medium through the first heat source 11 and the heat medium heat exchanger 13. Similarly, the second heat medium circuit 20 can be appropriately connected to each of the components as long as it has the heat medium heat exchanger 13, the second heat source 21, and the heater core 23 and circulates the second heat medium.

[0212] As for the refrigeration cycle 30, as long as the heat pumped up by the cycle can be dissipated to the second heat medium, the components of the refrigeration cycle 30 and the connection manner of the components may be appropriately changed. For example, in the above-mentioned embodiment, the first expansion valve 34 and the first evaporator 35 are connected in parallel with the second expansion valve 36 and the second evaporator 37, but the number of expansion valves and evaporators may be changed.

[0213] (d) In the above-described embodiment, the outside air radiator 14, the heat medium radiator 27, and the refrigerant radiator 41 are used as components corresponding to the heat radiating section 46, and the heat of the first heat medium, the second heat medium, or the refrigerant is radiated to the outside air, but the present invention is not limited to this embodiment. The heat radiating section 46 may radiate heat to the outside from a circulation circuit such as the first heat medium circuit 10, the second heat medium circuit 20, or the refrigerant connection section 40, and there is no particular limitation on the target from which heat is radiated.

[0214] The vehicle air conditioning system disclosed in this specification has the following features. (Item 1) a first heat medium circuit (10) that circulates a first heat medium through a first heat source (11, 11a) that generates heat as the vehicle travels; a second heat medium circuit (20) that circulates a second heat medium through a second heat source (21, 30, 42) capable of adjusting the amount of heat generated and a heater core (23) that heats, by heat exchange, the air to be supplied to a space to be air-conditioned; a heat medium heat exchanger (13) for exchanging heat between the first heat medium circulating through the first heat medium circuit and the second heat medium circulating through the second heat medium circuit; a control unit (60) that controls operations of the first heat medium circuit and the second heat medium circuit. (Item 2) The second heat source is 2. The vehicle air-conditioning system according to claim 1, which is configured by a refrigeration cycle (30) including: a compressor (31) which compresses and discharges a refrigerant; a heat medium refrigerant heat exchanger (32) which dissipates heat of the high-pressure refrigerant compressed by the compressor to the second heat medium; a pressure reduction section (34, 36) which reduces the pressure of the refrigerant flowing out of the heat medium refrigerant heat exchanger; and an evaporator (35, 37) which evaporates the refrigerant flowing out of the pressure reduction section. (Item 3) a heat amount adjustment unit (45) for adjusting the amount of heat input to the heat medium heat exchanger; 3. The vehicle air conditioner according to item 1 or 2, further comprising: a heat radiating section (46) that radiates the amount of heat that was not input to the heat medium heat exchanger by the heat amount adjusting section. (Item 4) the heat amount adjustment unit (45) includes a bypass flow path (15) through which the first heat medium flows so as to bypass the heat medium heat medium heat exchanger in the first heat medium circuit, and a flow rate adjustment unit (16) that adjusts a flow rate of the first heat medium flowing toward the bypass flow path and a flow rate of the first heat medium flowing toward the heat medium heat medium heat exchanger, 4. The vehicle air conditioning system according to claim 3, wherein the heat radiating portion (46) is an external radiator (14) that is disposed in a flow path of the first heat medium circuit and radiates heat of the first heat medium to the outside. (Item 5) the heat quantity adjustment unit (45) includes a heat medium bypass flow path (24) through which the second heat medium flows so as to bypass the heat medium heat medium heat exchanger in the second heat medium circuit, and a heat medium flow rate adjustment unit (25) that adjusts a flow rate of the second heat medium flowing toward the heat medium bypass flow path and a flow rate of the second heat medium flowing toward the heat medium heat medium heat exchanger, 4. The vehicle air conditioning device according to claim 3, wherein the heat radiating portion (46) is a heat medium radiator (27) that is arranged in the heat medium bypass flow path of the second heat medium circuit and radiates heat of the second heat medium flowing through the heat medium bypass flow path to the outside. (Item 6) a heat amount adjustment unit (45) for adjusting the amount of heat input to the heat medium heat exchanger; a heat dissipation section (46) that dissipates the amount of heat that was not input to the heat medium heat exchanger by the heat amount adjustment section, the heat amount adjustment unit includes a refrigerant bypass flow path (38) that causes the refrigerant discharged from the compressor to flow into the pressure reduction unit, bypassing the heat medium refrigerant heat exchanger, and a refrigerant flow rate adjustment unit (40) that adjusts a flow rate of the refrigerant flowing toward the refrigerant bypass flow path and a flow rate of the refrigerant flowing toward the heat medium refrigerant heat exchanger, 3. The vehicle air conditioning system according to claim 2, wherein the heat dissipation part is a refrigerant radiator (41) that is disposed in the refrigerant bypass passage in the refrigeration cycle and dissipates heat of the high-pressure refrigerant flowing through the refrigerant bypass passage to the outside. (Item 7) The control unit, regarding the flow of the first heat medium in the first heat medium circuit, a first circulation mode in which the first heat medium circulates via the external radiator, the first heat source, and the heat medium heat exchanger; a second circulation mode in which the first heat medium circulates via the external radiator and the first heat source without passing through the heat medium heat exchanger, or (Item 8) The control unit, regarding the flow of the first heat medium in the first heat medium circuit, 8. The vehicle air conditioning device according to item 7, wherein a portion of the first heat medium that has passed through the external radiator and the first heat source passes through the heat medium heat exchanger, and at the same time, a remaining portion of the first heat medium bypasses the heat medium heat exchanger. (Item 9) The control unit, regarding the flow of the first heat medium in the first heat medium circuit, 9. The vehicle air conditioning system according to item 8, wherein the system is switched to a fourth circulation mode in which the first heat medium circulates via the heat medium heat exchanger and the external radiator. (Item 10) 10. The vehicle air conditioning device according to any one of items 1 to 9, wherein the second heat source (21, 30, 42) is arranged upstream of the heat medium heat medium heat exchanger (13) with respect to a flow of the second heat medium in the second heat medium circuit. (Item 11) 11. The vehicle air conditioning device according to any one of items 1 to 10, wherein the heater core (23) is arranged upstream of the second heat source (21, 30, 42) with respect to a flow of the second heat medium in the second heat medium circuit. (Item 12) 6. The vehicle air-conditioning device according to claim 5, wherein the heat medium heat exchanger (13) is arranged upstream of a branch point (25) toward the heat medium bypass flow path, with respect to a flow of the second heat medium in the second heat medium circuit. (Item 13) When the second heat source is used for heating and at least the first heat source is used for heating, the control unit (60) The second heat source is operated, and in a state in which the second heat medium is circulating in the second heat medium circuit through at least the second heat source and the heater core, the first heat medium is put on hold in the first heat medium circuit until a temperature of the first heat medium satisfies a predetermined condition, 13. The vehicle air conditioning device according to any one of items 1 to 12, wherein, when a temperature of the first heat medium satisfies a predetermined condition, the second heat medium is circulated in the second heat medium circuit via at least the heater core and the heat medium heat medium heat exchanger, and the first heat medium is circulated in the first heat medium circuit via the first heat source and the heat medium heat medium heat exchanger. (Item 14) When the first heat source is in operation and heating is performed using the second heat source, the control unit (60) The first heat source is operated, and in a state in which the first heat medium is circulating through the first heat source and the heat medium heat exchanger in the first heat medium circuit, the second heat medium is circulated through the second heat source, the heater core, and the heat medium heat exchanger in the second heat medium circuit; 14. The vehicle air conditioning device according to any one of items 1 to 13, wherein, when a temperature of the second heat medium satisfies a predetermined condition, circulation of the first heat medium through the heat medium heat exchanger in the first heat medium circuit is stopped, and circulation of the second heat medium through at least the second heat source and the heater core is started in the second heat medium circuit. [Explanation of symbols]

[0215] 1. Vehicle air conditioning system 10 1st heat carrier circuit 11 1st heat source 11a Engine 13 Heat medium heat exchanger 20 Second heat carrier circuit 21 Second heat source 23 Heater core 60 Control device

Claims

1. a first heat medium circuit (10) that circulates a first heat medium through a first heat source (11, 11a) that generates heat as the vehicle travels; a second heat medium circuit (20) that circulates a second heat medium through a second heat source (21, 30, 42) capable of adjusting the amount of heat generated and a heater core (23) that heats, by heat exchange, the blown air to be supplied to a space to be air-conditioned; a heat medium heat exchanger (13) for exchanging heat between the first heat medium circulating through the first heat medium circuit and the second heat medium circulating through the second heat medium circuit; A control unit (60) that controls operations of the first heat medium circuit and the second heat medium circuit; A heat quantity adjustment unit (45) that adjusts the amount of heat input to the heat medium heat medium heat exchanger; A heat dissipation section (46) that dissipates the amount of heat not input to the heat medium heat exchanger by the heat amount adjustment section, The heat quantity adjustment unit (45) has a bypass flow path (15) through which the first heat medium flows so as to bypass the heat medium heat medium heat exchanger in the first heat medium circuit, and a flow rate adjustment unit (16) that adjusts a flow rate of the first heat medium flowing toward the bypass flow path and a flow rate of the first heat medium flowing toward the heat medium heat medium heat exchanger, The heat radiating portion (46) is an external radiator (14) that is disposed in a flow path of the first heat medium circuit and radiates heat of the first heat medium to the outside.

2. The second heat source is 2. The vehicle air conditioning system according to claim 1, further comprising a refrigeration cycle (30) including: a compressor (31) that compresses and discharges a refrigerant; a heat medium refrigerant heat exchanger (32) that dissipates heat of the high-pressure refrigerant compressed by the compressor to the second heat medium; a pressure reduction section (34, 36) that reduces the pressure of the refrigerant flowing out of the heat medium refrigerant heat exchanger; and an evaporator (35, 37) that evaporates the refrigerant flowing out of the pressure reduction section.

3. The heat quantity adjustment unit (45) has a heat medium bypass flow path (24) through which the second heat medium flows so as to bypass the heat medium heat medium heat exchanger in the second heat medium circuit, and a heat medium flow rate adjustment unit (25) that adjusts a flow rate of the second heat medium flowing toward the heat medium bypass flow path and a flow rate of the second heat medium flowing toward the heat medium heat medium heat exchanger, 2. The vehicle air conditioning system according to claim 1, wherein the heat dissipation portion is a heat medium radiator arranged in the heat medium bypass flow path of the second heat medium circuit and configured to radiate heat of the second heat medium flowing through the heat medium bypass flow path to the outside.

4. A heat quantity adjustment unit (45) that adjusts the amount of heat input to the heat medium heat medium heat exchanger; A heat dissipation section (46) that dissipates the amount of heat not input to the heat medium heat exchanger by the heat amount adjustment section, the heat quantity adjustment unit has a refrigerant bypass flow path (38) that causes the refrigerant discharged from the compressor to flow so as to bypass the heat medium refrigerant heat exchanger and flow into the pressure reduction unit in the refrigerant cycle, and a refrigerant flow rate adjustment unit (40) that adjusts a flow rate of the refrigerant flowing toward the refrigerant bypass flow path and a flow rate of the refrigerant flowing toward the heat medium refrigerant heat exchanger, 3. The vehicle air conditioning system according to claim 2, wherein the heat dissipation portion is a refrigerant radiator (41) disposed in the refrigerant bypass passage in the refrigeration cycle and configured to dissipate heat of the high-pressure refrigerant flowing through the refrigerant bypass passage to the outside.

5. The control unit is configured to: A first circulation mode in which the first heat medium circulates through the external radiator, the first heat source, and the heat medium heat exchanger; a first circulation mode in which the first heat medium circulates via the external radiator and the first heat source without passing through the heat medium heat exchanger, and a second circulation mode in which the first heat medium circulates via the external radiator and the first heat source without passing through the heat medium heat exchanger.

6. The control unit is configured to:

6. The vehicle air conditioning device according to claim 5, wherein a portion of the first heat medium that has passed through the external radiator and the first heat source passes through the heat medium heat exchanger, and at the same time, a remaining portion of the first heat medium bypasses the heat medium heat exchanger.

7. The control unit is configured to: The vehicle air conditioning system according to claim 6 , wherein the system is switched to a fourth circulation mode in which the first heat medium circulates via the heat medium heat exchanger and the external radiator.

8. 2. The vehicle air conditioning system according to claim 1, wherein the second heat source (21, 30, 42) is arranged upstream of the heat medium heat exchanger (13) with respect to a flow of the second heat medium in the second heat medium circuit.

9. 2. The vehicle air conditioning system according to claim 1, wherein the heater core (23) is disposed upstream of the second heat source (21, 30, 42) with respect to a flow of the second heat medium in the second heat medium circuit.

10. 4. The vehicle air conditioning device according to claim 3, wherein the heat medium heat exchanger (13) is arranged upstream of a branch point (25) to the heat medium bypass flow path with respect to a flow of the second heat medium in the second heat medium circuit.

11. When the control unit (60) uses at least the first heat source for heating from a state in which the second heat source is used for heating, The second heat source is operated, and in a state in which the second heat medium is circulating in the second heat medium circuit through at least the second heat source and the heater core, the first heat medium is put on hold in the first heat medium circuit until a temperature of the first heat medium satisfies a predetermined condition, 2. The vehicle air conditioning device according to claim 1, wherein when a temperature of the first heat medium satisfies a predetermined condition, the second heat medium is circulated through at least the heater core and the heat medium heat medium heat exchanger in the second heat medium circuit, and the first heat medium is circulated through the first heat source and the heat medium heat medium heat exchanger in the first heat medium circuit.

12. When heating is performed using the second heat source from a state in which the first heat source is operating, the control unit (60) The first heat source is operated, and in a state in which the first heat medium is circulating through the first heat source and the heat medium heat exchanger in the first heat medium circuit, the second heat medium is circulated through the second heat source, the heater core, and the heat medium heat exchanger in the second heat medium circuit; 2. The vehicle air conditioning device according to claim 1, wherein, when a temperature of the second heat medium satisfies a predetermined condition, circulation of the first heat medium through the heat medium heat exchanger in the first heat medium circuit is stopped, and circulation of the second heat medium through at least the second heat source and the heater core in the second heat medium circuit is performed.

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