Refrigeration Cycle Equipment

Abstract

To perform defrosting as efficient as possible in a refrigeration cycle device absorbing heat from ambient air.SOLUTION: A refrigeration cycle device comprises: a heat radiation part 12 which radiates heat of coolant discharged from a compressor 11; a decompression part 16 which reduces pressure of the coolant radiated at the heat radiation part; an evaporation part 17 which cools a heat medium by thermally exchanging the heat medium with the coolant depressed at the decompression part; an ambient air endothermic part 45 which causes the heat medium cooled at the evaporation part to absorb heat from the ambient air; heat sources 25, 82 which heat the heat medium by radiating heat to the heat medium; first circulation circuits 20, 80 which circulate the heat medium to the heat sources; a second circulation circuit 30 which circulates the heat medium between the evaporation part and the ambient air endothermic part; and flow channel changeover parts 26, 60, 83 which determine whether or not defrost of the ambient air endothermic part is necessary and circulate the heat medium by the first circulation circuits and the second circulation circuit individually when it is determined that the defrost of the ambient air endothermic part is unnecessary, and meanwhile, switch a flow channel of the heat medium so as to circulate the heat medium of the first circulation circuits to the ambient air endothermic part when it is determined that the defrost of the ambient air endothermic part is necessary.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present invention relates to a refrigeration cycle device that absorbs heat from outside air. [Background technology]

[0002] Conventionally, Patent Document 1 describes a heat pump system equipped with an LT radiator as an outside air heat sink. In the LT radiator, cooling water cooled by a refrigerant in a chiller absorbs heat from outside air. When cooled in the chiller, the temperature of the cooling water may become 0°C or lower. When the temperature of the cooling water becomes 0°C or lower, moisture in the outside air freezes on the surface of the LT radiator, causing frost to form (so-called frost formation).

[0003] In this conventional technology, cooling water heated by a water-cooled condenser is supplied to the LT radiator, and frost adhering to the surface of the LT radiator is melted and removed (so-called defrosting). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 6399060 Summary of the Invention [Problem to be solved by the invention]

[0005] The above-mentioned conventional techniques make no mention of when and how to most efficiently defrost a heat pump system (in other words, a refrigeration cycle device that absorbs heat from outside air).

[0006] In view of the above, an object of the present invention is to perform defrosting as efficiently as possible in a refrigeration cycle device that absorbs heat from outside air. [Means for solving the problem]

[0007] In order to achieve the above object, the refrigeration cycle device according to claim 1 comprises: a compressor (11) that draws in, compresses, and discharges a refrigerant; a heat dissipation section (12) that dissipates heat from a refrigerant discharged from the compressor; a pressure reducing section (16) for reducing the pressure of the refrigerant whose heat has been radiated in the heat radiating section; an evaporation section (17) that exchanges heat between the refrigerant decompressed in the decompression section and a heat medium to evaporate the refrigerant and cool the heat medium; an outside air heat absorption section (45) for causing the heat medium cooled in the evaporation section to absorb heat from outside air; a heat source (25, 82) that dissipates heat into a heat medium to heat the heat medium; a first circulation circuit (20, 80) for circulating a heat medium through the heat source; a second circulation circuit (30) for circulating a heat medium between the evaporation section and the outside air heat absorption section; Determine whether defrosting of the outdoor air heat intake section is necessary; When it is determined that defrosting of the outdoor air heat absorption section is not necessary, the heat medium is circulated separately in the first circulation circuit and the second circulation circuit, a flow path switching unit (26, 60, 83) that switches a flow path of the heat medium so that the heat medium in the first circulation circuit is circulated to the outdoor air heat absorption unit when it is determined that defrosting of the outdoor air heat absorption unit is necessary; an air heating section (22) that heats the air by dissipating heat of a heat medium into the air blown into the vehicle compartment, The heat dissipation section dissipates heat from the refrigerant discharged from the compressor to the heat medium, The heat source includes a first heat source (82) that dissipates waste heat generated during operation to a heat medium, and a second heat source (25) that generates heat for heating air; the first circulation circuit includes a heat storage circuit (80) in which a heat medium circulates through the first heat source to store waste heat of the first heat source in the heat medium, and a heating circuit (20) that circulates the heat medium through the heat dissipation section, the second heat source, and the air heating section; When the flow path switching unit determines that defrosting of the outdoor air heat absorption unit is necessary, the flow path switching unit switches the flow path of the heat medium so that the heat medium in the heat storage circuit circulates to the outdoor air heat absorption unit without circulating to the second heat source and the air heating unit, and when the flow path switching unit determines that defrosting of the outdoor air heat absorption unit is necessary after circulating the heat medium in the heat storage circuit to the outdoor air heat absorption unit, the flow path switching unit switches the flow path of the heat medium so that the heat medium in the heating circuit circulates to the outdoor air heat absorption unit without circulating to the first heat source. Air Heating Section The flow path of the heat medium is switched so that the heat medium flows in parallel to the outside air heat absorption section.

[0008] According to this, since defrosting of the outdoor air heat absorbing portion can be reliably performed when defrosting is required, defrosting can be performed efficiently.

[0009] In addition, the reference symbols in parentheses for each means described in this column and in the claims indicate the correspondence with the specific means described in the embodiments described later. [Brief description of the drawings]

[0010] [Figure 1] 1 is an overall configuration diagram of a refrigeration cycle device according to a first embodiment. [Diagram 2] 2 is a block diagram showing an electric control unit of the refrigeration cycle device in the first embodiment. FIG. [Diagram 3] FIG. 2 is an overall configuration diagram showing an operating state of the refrigeration cycle device in a waste heat defrosting mode in the first embodiment. [Figure 4] FIG. 2 is an overall configuration diagram showing an operating state of the refrigeration cycle device in a heating heat defrosting mode in the first embodiment. [Diagram 5] 5 is a flowchart showing a control process of a control program in the first embodiment. [Figure 6] 4 is a determination diagram used to determine whether frost has formed on a common radiator in the control process of the control program in the first embodiment. FIG. [Figure 7] 4 is a time chart showing an example of an operation of the refrigeration cycle device in the first embodiment. [Figure 8] 5 is a time chart showing another operation example of the refrigeration cycle device in the first embodiment. [Figure 9] FIG. 11 is an overall configuration diagram of a refrigeration cycle device according to a second embodiment. [Figure 10] FIG. 11 is an overall configuration diagram showing an operating state in a heating heat defrosting mode of a refrigeration cycle device in a second embodiment. [Figure 11] 13 is a flowchart showing a control process of a control program in a third embodiment. [Figure 12] 10 is a time chart showing an example of an operation of the refrigeration cycle device in the third embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, the embodiments will be described with reference to the drawings. In the following embodiments, the same or equivalent parts are denoted by the same reference numerals in the drawings.

[0012] (First embodiment) Hereinafter, an embodiment will be described with reference to the drawings. A vehicle air conditioner 1 shown in Fig. 1 is an air conditioner that adjusts the temperature of a vehicle interior space (in other words, a space to be air-conditioned) to an appropriate temperature. The vehicle air conditioner 1 has a refrigeration cycle device 10.

[0013] The refrigeration cycle device 10 is mounted on an electric vehicle, a hybrid vehicle, or the like. An electric vehicle is a vehicle that obtains driving force for running the vehicle from an electric motor for running. A hybrid vehicle is a vehicle that obtains driving force for running the vehicle from an engine (in other words, an internal combustion engine) and an electric motor for running.

[0014] The refrigeration cycle device 10 is a vapor compression type refrigerator including a compressor 11, a condenser 12, a first expansion valve 13, an air-side evaporator 14, a constant pressure valve 15, a second expansion valve 16, and a cooling water-side evaporator 17. The refrigeration cycle device 10 of this embodiment uses a fluorocarbon refrigerant as the refrigerant, and configures a subcritical refrigeration cycle in which the high-pressure side refrigerant pressure does not exceed the critical pressure of the refrigerant.

[0015] The second expansion valve 16 and the coolant-side evaporator 17 are arranged in parallel with the first expansion valve 13, the air-side evaporator 14, and the constant pressure valve 15 in the refrigerant flow.

[0016] A first refrigerant circulation circuit and a second refrigerant circulation circuit are formed in the refrigeration cycle device 10. In the first refrigerant circulation circuit, the refrigerant circulates through the compressor 11, the condenser 12, the first expansion valve 13, the air-side evaporator 14, the constant pressure valve 15, and the compressor 11 in that order. In the second refrigerant circulation circuit, the refrigerant circulates through the compressor 11, the condenser 12, the second expansion valve 16, and the cooling water-side evaporator 17 in that order.

[0017] The compressor 11 is an electric compressor driven by power supplied from a battery, and draws in, compresses, and discharges the refrigerant of the refrigeration cycle device 10. The electric motor of the compressor 11 is controlled by a control device 60 shown in Fig. 2. The compressor 11 may be a variable displacement compressor driven by a belt.

[0018] The condenser 12 is a high-pressure side heat exchanger that exchanges heat between the high-pressure side refrigerant discharged from the compressor 11 and the cooling water of the high-temperature cooling water circuit 20. The condenser 12 is a heat dissipation section that exchanges heat between the refrigerant discharged from the compressor 11 and the cooling water, thereby dissipating heat from the refrigerant to heat the cooling water.

[0019] In the case of an electric vehicle, the compressor 11 and the condenser 12 are arranged in a motor room of the vehicle. The motor room is a space that houses an electric motor for driving the vehicle. In the case of a hybrid vehicle, the compressor 11 and the condenser 12 are arranged in an engine room of the vehicle. The engine room is a space that houses an engine.

[0020] The condenser 12 has a condensing portion 12a, a receiver 12b, and a supercooling portion 12c. In the condenser 12, the refrigerant flows through the condensing portion 12a, the receiver 12b, and the supercooling portion 12c in this order.

[0021] The condensation section 12a exchanges heat between the high-pressure side refrigerant discharged from the compressor 11 and the cooling water of the high-temperature cooling water circuit 20, thereby condensing the high-pressure side refrigerant.

[0022] The receiver 12b is a gas-liquid separation section that separates the high-pressure refrigerant flowing out from the condenser 12 into gas and liquid phases, and causes the separated liquid phase refrigerant to flow downstream, while storing surplus refrigerant in the cycle.

[0023] The subcooling section 12c exchanges heat between the liquid-phase refrigerant flowing out from the receiver 12b and the cooling water in the high-temperature cooling water circuit 20 to subcool the liquid-phase refrigerant.

[0024] The cooling water in the high-temperature cooling water circuit 20 is a fluid serving as a heat medium. The cooling water in the high-temperature cooling water circuit 20 is a high-temperature heat medium. In this embodiment, a liquid containing at least ethylene glycol, dimethylpolysiloxane or a nanofluid, or an antifreeze liquid is used as the cooling water in the high-temperature cooling water circuit 20. The high-temperature cooling water circuit 20 is a first circulation circuit in which the cooling water circulates. The high-temperature cooling water circuit 20 is a high-temperature heat medium circuit in which a high-temperature heat medium circulates.

[0025] The first expansion valve 13 is Supercooled section 12c The first expansion valve 13 is a first pressure reducing section that reduces the pressure and expands the liquid-phase refrigerant flowing out from the first expansion valve 13. The first expansion valve 13 is an electric expansion valve. The electric expansion valve is an electric variable throttle mechanism that includes a valve body configured to be able to change the throttle opening degree, and an electric actuator that changes the opening degree of the valve body.

[0026] The first expansion valve 13 is a refrigerant flow switching unit that switches between a state in which the refrigerant flows through the air-side evaporator 14 and a state in which the refrigerant does not flow through the air-side evaporator 14. The operation of the first expansion valve 13 is controlled by a control signal output from the control device 60.

[0027] The first expansion valve 13 may be a mechanical temperature expansion valve. When the first expansion valve 13 is a mechanical temperature expansion valve, an opening / closing valve for opening and closing the refrigerant flow path on the first expansion valve 13 side needs to be provided separately from the first expansion valve 13.

[0028] The air-side evaporator 14 is an evaporator that evaporates the refrigerant by exchanging heat between the refrigerant flowing out from the first expansion valve 13 and the air blown into the vehicle cabin. In the air-side evaporator 14, the refrigerant absorbs heat from the air blown into the vehicle cabin. The air-side evaporator 14 is an air cooler that cools the air blown into the vehicle cabin.

[0029] The constant pressure valve 15 is a pressure adjustment unit that maintains the pressure of the refrigerant at the outlet side of the air-side evaporator 14 at a predetermined value. The constant pressure valve 15 is composed of a mechanical variable throttle mechanism. Specifically, the constant pressure valve 15 reduces the passage area (i.e., the throttle opening) of the refrigerant passage when the refrigerant pressure at the outlet side of the air-side evaporator 14 falls below a predetermined value, and increases the passage area (i.e., the throttle opening) of the refrigerant passage when the refrigerant pressure at the outlet side of the air-side evaporator 14 exceeds the predetermined value. The gas-phase refrigerant whose pressure has been adjusted by the constant pressure valve 15 is sucked into the compressor 11 and compressed.

[0030] In cases where there is little fluctuation in the flow rate of the refrigerant circulating through the cycle, the constant pressure valve 15 may be replaced by a fixed throttle such as an orifice or a capillary tube.

[0031] The second expansion valve 16 is a second pressure reducing section that reduces the pressure and expands the liquid phase refrigerant flowing out from the condenser 12. The second expansion valve 16 is an electric expansion valve. The electric expansion valve is an electric variable throttling mechanism including a valve body configured to be able to change the throttling opening degree and an electric actuator that changes the opening degree of the valve body. The second expansion valve 16 is capable of fully closing the refrigerant flow path.

[0032] The second expansion valve 16 is a refrigerant flow switching unit that switches between a state in which the refrigerant flows and a state in which the refrigerant does not flow to the coolant-side evaporator 17. The operation of the second expansion valve 16 is controlled by a control signal output from the control device 60.

[0033] The second expansion valve 16 may be a mechanical temperature expansion valve. When the second expansion valve 16 is a mechanical temperature expansion valve, an opening / closing valve for opening and closing the refrigerant flow path on the second expansion valve 16 side needs to be provided separately from the second expansion valve 16.

[0034] The coolant-side evaporator 17 is an evaporation section that evaporates the refrigerant by heat exchange between the refrigerant flowing out from the second expansion valve 16 and the coolant in the low-temperature coolant circuit 30. In the coolant-side evaporator 17, the refrigerant absorbs heat from the coolant in the low-temperature coolant circuit 30. The coolant-side evaporator 17 is a heat medium cooler that cools the coolant in the low-temperature coolant circuit 30. The gas-phase refrigerant evaporated in the coolant-side evaporator 17 is sucked into the compressor 11 and compressed.

[0035] The cooling water in the low-temperature coolant circuit 30 is a fluid serving as a heat medium. The cooling water in the low-temperature coolant circuit 30 is a low-temperature heat medium. In this embodiment, a liquid containing at least ethylene glycol, dimethylpolysiloxane or a nanofluid, or an antifreeze liquid is used as the cooling water in the low-temperature coolant circuit 30. The low-temperature coolant circuit 30 is a low-temperature heat medium circuit in which a low-temperature heat medium circulates. The low-temperature coolant circuit 30 is a second circulation circuit in which the cooling water circulates.

[0036] In the high-temperature coolant circuit 20, a condenser 12, a high-temperature side pump 21, a heater core 22, a common radiator 45, a reserve tank 24, and an electric heater 25 are arranged.

[0037] The high-temperature side pump 21 is a heat medium pump that draws in and discharges cooling water. The high-temperature side pump 21 is an electric pump. The high-temperature side pump 21 is an electric pump with a constant discharge flow rate, but the high-temperature side pump 21 may be an electric pump with a variable discharge flow rate.

[0038] The heater core 22 is an air heating section that exchanges heat between the coolant in the high-temperature coolant circuit 20 and the air blown into the vehicle cabin to heat the air blown into the vehicle cabin. In the heater core 22, the coolant dissipates heat to the air blown into the vehicle cabin. The heater core 22 is a heat utilization section that utilizes the heat of the coolant heated by the condenser 12. The high-temperature coolant circuit 20 is a heating circuit that circulates the coolant through the heater core 22.

[0039] The common radiator 45 is a radiator that exchanges heat between the coolant in the high-temperature coolant circuit 20 and the outside air, thereby radiating heat from the coolant to the outside air. The common radiator 45 is a radiator shared by the high-temperature coolant circuit 20 and the low-temperature coolant circuit 30.

[0040] The condenser 12 and the high-temperature side pump 21 are disposed in a condenser flow path 20a. The condenser flow path 20a is a flow path through which the cooling water of the high-temperature cooling water circuit 20 flows.

[0041] The flow direction of the cooling water in the condenser 12 is opposite to the flow direction of the refrigerant in the condenser 12. That is, in the condenser 12, the cooling water flows through the supercooling portion 12c and the condensing portion 12a in this order.

[0042] The heater core 22 is disposed in a heater core flow path 20b. The heater core flow path 20b is a flow path through which the coolant of the high-temperature coolant circuit 20 flows.

[0043] The common radiator 45 is disposed in the radiator flow path 20c. The radiator flow path 20c is a flow path through which the coolant of the high-temperature coolant circuit 20 flows in parallel with the heater core 22.

[0044] A first three-way valve 26 is disposed at a branching point 20d of the high-temperature coolant circuit 20. The branching point 20d is a branching point where the condenser passage 20a branches into a heater core passage 20b and a radiator passage 20c.

[0045] The first three-way valve 26 is a flow path switching unit that switches the flow path of the coolant in the high-temperature coolant circuit 20. The first three-way valve 26 opens and closes the heater core flow path 20b and the radiator flow path 20c. The first three-way valve 26 adjusts the opening degree of the heater core flow path 20b and the opening degree of the radiator flow path 20c. The first three-way valve 26 adjusts the opening ratio between the heater core flow path 20b and the radiator flow path 20c. The first three-way valve 26 controls the flow rate of the coolant flowing through the heater core 22 and the Common Radiator 45 The flow rate ratio of the cooling water flowing through the intake duct is adjusted.

[0046] A reserve tank 24 is disposed at the junction 20e of the high-temperature coolant circuit 20. The junction 20e is a junction where the heater core flow passage 20b and the radiator flow passage 20c join with the condenser flow passage 20a.

[0047] The reserve tank 24 is a storage unit that stores surplus cooling water. By storing surplus cooling water in the reserve tank 24, it is possible to suppress a decrease in the amount of cooling water circulating through each flow path.

[0048] The reserve tank 24 is a sealed reserve tank or an open-to-atmosphere reserve tank. The sealed reserve tank is a reserve tank that keeps the pressure at the liquid surface of the stored cooling water at a predetermined pressure. The open-to-atmosphere reserve tank is a reserve tank that keeps the pressure at the liquid surface of the stored cooling water at atmospheric pressure.

[0049] The reserve tank 24 has a gas-liquid separation function for separating air bubbles present in the cooling water from the cooling water.

[0050] The electric heater 25 is disposed downstream of the branching portion 20d of the high-temperature coolant circuit 20 and upstream of the heater core 22. The electric heater 25 is a heat source device that generates Joule heat by receiving power from a battery to heat the coolant. The electric heater 25 is a second heat source. The electric heater 25 auxiliarily heats the coolant in the high-temperature coolant circuit 20. The electric heater 25 is controlled by the control device 60.

[0051] In the low-temperature coolant circuit 30, a low-temperature side pump 31, a coolant side evaporator 17, and a common radiator 45 are arranged.

[0052] The low-temperature side pump 31 is a heat medium pump that draws in and discharges coolant. The low-temperature side pump 31 is an electric pump. The common radiator 45 is an outside air heat absorption section that exchanges heat between the coolant in the low-temperature coolant circuit 30 and outside air, causing the coolant in the low-temperature coolant circuit 30 to absorb heat from the outside air.

[0053] A part of the low-temperature coolant circuit 30 merges with the radiator flow path 20c of the high-temperature coolant circuit 20. The common radiator 45 is disposed at a portion of the low-temperature coolant circuit 30 that merges with the radiator flow path 20c of the high-temperature coolant circuit 20. Therefore, both the coolant of the radiator flow path 20c of the high-temperature coolant circuit 20 and the coolant of the low-temperature coolant circuit 30 can flow through the common radiator 45.

[0054] The common radiator 45 and the exterior blower 40 are disposed at the front of the vehicle. Therefore, when the vehicle is moving, the air generated by the movement of the vehicle can be directed at the common radiator 45.

[0055] The exterior blower 40 is an outside air blowing section that blows outside air towards the common radiator 45. The exterior blower 40 is an electric blower in which a fan is driven by an electric motor. The operation of the exterior blower 40 is controlled by the control device 60.

[0056] The common radiator 45 and the exterior blower 40 are disposed at the front of the vehicle. Therefore, when the vehicle is moving, the air generated by the movement of the vehicle can be directed at the common radiator 45.

[0057] The air-side evaporator 14 and the heater core 22 are housed in an air conditioning casing 51 of an interior air conditioning unit 50. The interior air conditioning unit 50 is disposed inside an instrument panel (not shown) at the front of the vehicle interior. The air conditioning casing 51 is an air passage forming member that forms an air passage.

[0058] The heater core 22 is disposed in an air passage in an air conditioning casing 51, downstream of the air flow of the air-side evaporator 14. In the air conditioning casing 51, an inside / outside air switching box 52 and an indoor blower 53 are disposed.

[0059] The inside / outside air switching box 52 is an inside / outside air switching section that switches between introducing inside air and outside air into the air passage in the air conditioning casing 51. The indoor blower 53 sucks in the inside air and outside air introduced into the air passage in the air conditioning casing 51 through the inside / outside air switching box 52 and blows it. The operation of the indoor blower 53 is controlled by the control device 60.

[0060] An air mix door 54 is disposed between the air-side evaporator 14 and the heater core 22 in the air passage in the air conditioning casing 51. The air mix door 54 adjusts the ratio of the amount of cold air that flows into the heater core 22 and the amount of cold air that flows through the cold air bypass passage 55 among the amount of cold air that has passed through the air-side evaporator 14.

[0061] The cold air bypass passage 55 is an air passage through which the cold air that has passed through the air side evaporator 14 flows by bypassing the heater core 22 .

[0062] The air mix door 54 is a revolving door having a rotary shaft rotatably supported relative to the air conditioning casing 51 and a door base plate portion connected to the rotary shaft. By adjusting the opening position of the air mix door 54, the temperature of the conditioned air blown out from the air conditioning casing 51 into the vehicle compartment can be adjusted to a desired temperature.

[0063] The rotation shaft of the air mix door 54 is driven by a servo motor 56. The operation of the air mix door servo motor 56 is controlled by a control device 60.

[0064] The air mix door 54 may be a sliding door that slides in a direction substantially perpendicular to the air flow. The sliding door may be a plate-like door made of a rigid body, or may be a film door made of a flexible film material.

[0065] The conditioned air whose temperature has been adjusted by the air mix door 54 is blown out into the vehicle compartment from an air outlet 57 formed in the air conditioning casing 51 .

[0066] In the heat storage circuit 80, a heat storage pump 81, a heat waste device 82, the common radiator 45, and a second three-way valve 83 are arranged.

[0067] The cooling water of the heat storage circuit 80 is a fluid serving as a heat medium. The cooling water of the heat storage circuit 80 is a high-temperature heat medium. In this embodiment, a liquid containing at least ethylene glycol, dimethylpolysiloxane, or a nanofluid, or an antifreeze liquid is used as the cooling water of the heat storage circuit 80. The heat storage circuit 80 is a high-temperature heat medium circuit in which a high-temperature heat medium circulates.

[0068] The heat storage pump 81 is a heat medium pump that draws in and discharges cooling water. The heat storage pump 81 is an electric pump.

[0069] The waste heat device 82 is a heat source device that generates waste heat when it is operated. The waste heat device 82 is a first heat source. For example, the waste heat device 82 is an inverter. The waste heat device 82 may be a motor generator, a charger, or the like. storage The heat pump 81 and the waste heat device 82 are disposed in a waste heat device flow path 80a.

[0070] The common radiator 45 is disposed in the defrost flow path 80b. The defrost flow path 80b is a flow path through which the cooling water of the heat storage circuit 80 flows. The circulation flow path 80c is a flow path through which the cooling water of the heat storage circuit 80 flows in parallel to the defrost flow path 80b.

[0071] A part of the defrost flow path 80b merges with the radiator flow path 20c of the high-temperature coolant circuit 20 and the low-temperature coolant circuit 30. The common radiator 45 is disposed in a part of the defrost flow path 80b where the radiator flow path 20c of the high-temperature coolant circuit 20 and the low-temperature coolant circuit 30 merge. Therefore, the coolant of the radiator flow path 20c of the high-temperature coolant circuit 20, the coolant of the low-temperature coolant circuit 30, and the defrost flow path 80b of the heat storage circuit 80 can flow through the common radiator 45.

[0072] A second three-way valve 83 is disposed at a branching point 80d of the heat storage circuit 80. The branching point 80d is a branching point where the waste heat device flow path 80a branches into a defrosting flow path 80b and a circulation flow path 80c. The defrosting flow path 80b and the circulation flow path 80c merge into the waste heat device flow path 80a at a merging point 80e.

[0073] The second three-way valve 83 is a flow path switching unit that switches the flow path of the cooling water in the heat storage circuit 80. The second three-way valve 83 opens and closes the defrost flow path 80b and the circulation flow path 80c. The second three-way valve 83 adjusts the opening degree of the defrost flow path 80b and the opening degree of the circulation flow path 80c. The second three-way valve 83 adjusts the opening degree ratio between the defrost flow path 80b and the circulation flow path 80c. The second three-way valve 83 adjusts the flow rate ratio of the cooling water flowing through the defrost flow path 80b and the cooling water flowing through the circulation flow path 80c.

[0074] The control device 60 shown in Fig. 2 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 a control program stored in the ROM. Various controlled devices are connected to the output side of the control device 60. The control device 60 is a control unit that controls the operation of the various controlled devices.

[0075] The controlled devices controlled by the control device 60 include the compressor 11, the first expansion valve 13, the second expansion valve 16, the first three-way valve 26, the outdoor blower 40, the indoor blower 53, the servo motor 56 for the air mix door, and the second three-way valve 83.

[0076] In the control device 60, software and hardware that controls the electric motor of the compressor 11 constitute a refrigerant discharge capacity control section. In the control device 60, software and hardware that controls the first expansion valve 13 and the second expansion valve 16 constitute a throttling control section.

[0077] The software and hardware of the control device 60 that controls the first three-way valve 26 and the second three-way valve 83 constitute a three-way valve control unit. The control device 60, the first three-way valve 26, and the second three-way valve 83 constitute a flow path switching unit that switches the flow path of the cooling water.

[0078] Of the control device 60, the software and hardware that controls the outdoor blower 40 is an outside air blowing capacity control unit.

[0079] In the control device 60, the software and hardware that controls the indoor blower 53 is an air blowing capacity control section.

[0080] The software and hardware of the control device 60 that controls the servo motor 56 for the air mix door constitutes an air volume ratio control section.

[0081] A variety of control sensors are connected to the input side of the control device 60. The various control sensors include an inside air temperature sensor 61, an outside air temperature sensor 62, a solar radiation sensor 63, a high-temperature coolant temperature sensor 64, a radiator temperature sensor 65, a heat storage coolant temperature sensor 66, and the like.

[0082] The inside air temperature sensor 61 detects the temperature Tr inside the vehicle cabin. The outside air temperature sensor 62 detects the outside air temperature Tam. The solar radiation sensor 63 detects the amount of solar radiation Ts inside the vehicle cabin.

[0083] The high-temperature coolant temperature sensor 64 detects the temperature TWH of the coolant in the high-temperature coolant circuit 20. For example, the high-temperature coolant temperature sensor 64 detects the temperature of the coolant flowing out from the electric heater 25.

[0084] The radiator temperature sensor 65 detects the temperature TWR of the coolant flowing into the common radiator 45. The heat storage coolant temperature sensor 66 detects the temperature TWW of the coolant in the heat storage circuit 80. For example, the heat storage coolant temperature sensor 66 detects the temperature of the coolant flowing out from the waste heat equipment 82.

[0085] Various operation switches (not shown) are connected to the input side of the control device 60. The various operation switches are provided on an operation panel 70 and are operated by a passenger. The operation panel 70 is disposed near the instrument panel at the front of the vehicle interior. Operation signals are input to the control device 60 from the various operation switches.

[0086] The various operation switches include an auto switch, an air conditioner switch, a temperature setting switch, etc. The auto switch is a switch for setting and canceling automatic control operation of the vehicle air conditioner 1. The air conditioner switch is a switch for setting whether or not to cool the air in the interior air conditioning unit 50. The temperature setting switch is a switch for setting the set temperature in the vehicle cabin.

[0087] Next, the operation of the above configuration will be described. Below, the operation of the control device 60 when the auto switch on the operation panel 70 is turned on by the occupant will be described. When the air conditioner switch on the operation panel 70 is turned on by the occupant, the operation mode is switched based on the target blown temperature TAO and the control map shown in Fig. 3. The operation modes include at least a cooling mode and a dehumidifying and heating mode.

[0088] The target blown air temperature TAO is a target temperature of the air blown into the vehicle compartment. The control device 60 calculates the target blown air temperature TAO based on the following formula.

[0089] TAO=Kset×Tset-Kr×Tr-Kam×Tam-Ks×Ts+C In this formula, Tset is the vehicle interior temperature set by the temperature setting switch on the operation panel 70, Tr is the inside air temperature detected by the inside air temperature sensor 61, Tam is the outside air temperature detected by the outside air temperature sensor 62, and Ts is the amount of solar radiation detected by the solar radiation sensor 63. Kset, Kr, Kam, and Ks are control gains, and C is a correction constant.

[0090] When the target air outlet temperature TAO is in the low temperature range, the mode is switched to cooling mode. When the target air outlet temperature TAO is in the high temperature range, the mode is switched to dehumidifying heating mode.

[0091] In the dehumidifying and heating mode, the air blown into the vehicle cabin is cooled and dehumidified by the air-side evaporator 14, and the air cooled and dehumidified by the air-side evaporator 14 is heated by the heater core 22 to dehumidify and heat the vehicle cabin.

[0092] When the air conditioner switch on the operation panel 70 is turned off by the passenger and the target air outlet temperature TAO is in the high temperature range, the control device 60 switches to the heating mode.

[0093] In the heating mode, the air blown into the vehicle compartment is heated by the heater core 22 without being cooled and dehumidified by the air-side evaporator 14, thereby heating the vehicle compartment.

[0094] Next, the operation in the cooling mode, the dehumidifying and heating mode, and the heating mode will be described. In the cooling mode, the dehumidifying and heating mode, the control device 60 determines the operating state of various control devices connected to the control device 60 (in other words, the control signals to be output to the various control devices) based on the target blowing temperature TAO and the detection signals of the above-mentioned sensor group.

[0095] (1) Cooling mode In the cooling mode, the control device 60 operates the compressor 11, the high-temperature side pump 21, and the heat storage pump 81, and stops the low-temperature side pump 31. In the cooling mode, the control device 60 opens the first expansion valve 13 at a throttled opening and closes the second expansion valve 16. In the cooling mode, the control device 60 controls the first three-way valve 26 to open both the heater core flow path 20b and the radiator flow path 20c, and controls the second three-way valve 83 to close the defrost flow path 80b and open the circulation flow path 80c.

[0096] As a result, in the refrigeration cycle device 10 in the cooling mode, the refrigerant flows as follows: That is, high-pressure refrigerant discharged from the compressor 11 flows into the condenser 12. The refrigerant that flows into the condenser 12 dissipates heat to the cooling water in the high-temperature coolant circuit 20. As a result, the refrigerant is cooled and condensed in the condenser 12.

[0097] The refrigerant flowing out from the condenser 12 flows into the first expansion valve 13, where it is decompressed and expanded to become a low-pressure refrigerant. The low-pressure refrigerant decompressed by the first expansion valve 13 flows into the air-side evaporator 14, where it absorbs heat from the air blown into the vehicle cabin and evaporates. This cools the air blown into the vehicle cabin.

[0098] Then, the refrigerant flowing out from the air-side evaporator 14 flows to the suction side of the compressor 11 and is compressed again by the compressor 11.

[0099] In this way, in the cooling mode, the low-pressure refrigerant absorbs heat from the air in the air-side evaporator 14, and the cooled air is blown out into the vehicle interior. This makes it possible to cool the vehicle interior.

[0100] In the cooling mode, the coolant in the high-temperature coolant circuit 20 circulates through the common radiator 45. Common Radiator 45 The heat is dissipated from the cooling water to the outside air.

[0101] At this time, the coolant from the high-temperature coolant circuit 20 also circulates through the heater core 22, but the amount of heat dissipated from the coolant to the air in the heater core 22 is adjusted by the air mix door 54.

[0102] The control signal output to the servo motor of the air mix door 54 is determined so that the conditioned air whose temperature has been adjusted by the air mix door 54 has a target blowing temperature TAO. Specifically, the opening degree of the air mix door 54 is determined based on the target blowing temperature TAO, the temperature of the air-side evaporator 14, the temperature TW of the coolant in the high-temperature coolant circuit 20, and the like.

[0103] In the heat storage circuit 80 in the cooling mode, the cooling water circulates through the waste heat device 82, and the waste heat of the waste heat device 82 is stored in the cooling water.

[0104] (2) Dehumidifying heating mode In the dehumidifying and heating mode, the control device 60 operates the compressor 11, the high-temperature side pump 21, the low-temperature side pump 31, and the heat storage pump 81. In the dehumidifying and heating mode, the control device 60 opens the first expansion valve 13 and the second expansion valve 16 at a throttled opening. In the dehumidifying and heating mode, the control device 60 controls the first three-way valve 26 to open the heater core flow path 20b and close the radiator flow path 20c, and controls the second three-way valve 83 to close the defrost flow path 80b and open the circulation flow path 80c.

[0105] In the refrigeration cycle device 10 in the dehumidifying and heating mode, the refrigerant flows as follows. Pressure The high-pressure refrigerant discharged from the compressor 11 flows into the condenser 12 and dissipates heat through heat exchange with the cooling water in the high-temperature cooling water circuit 20. As a result, the cooling water in the high-temperature cooling water circuit 20 is heated.

[0106] The refrigerant flowing out of the condenser 12 flows into the first expansion valve 13, where it is decompressed and expanded to become a low-pressure refrigerant. The low-pressure refrigerant decompressed by the first expansion valve 13 flows into the air-side evaporator 14, where it absorbs heat from the air blown into the vehicle cabin and evaporates. This cools and dehumidifies the air blown into the vehicle cabin.

[0107] Then, the refrigerant flowing out from the air-side evaporator 14 flows to the suction side of the compressor 11 and is compressed again by the compressor 11.

[0108] At the same time, in the refrigeration cycle apparatus 10, the refrigerant flowing out from the condenser 12 flows into the second expansion valve 16, where it is decompressed and expanded to become a low-pressure refrigerant. The low-pressure refrigerant decompressed by the second expansion valve 16 flows into the coolant-side evaporator 17, where it absorbs heat from the coolant in the low-temperature coolant circuit 30 and evaporates. As a result, the coolant in the low-temperature coolant circuit 30 is cooled.

[0109] Then, the refrigerant flowing out from the coolant-side evaporator 17 flows to the suction side of the compressor 11 and is compressed again by the compressor 11.

[0110] In the dehumidification heating mode, the high-temperature coolant circuit 20 circulates coolant between the condenser 12 and the heater core 22. Common Radiator 45 No cooling water circulates in the

[0111] The control signal output to the servo motor of the air mix door 54 is as follows: H The air passage of the heater core 22 is fully opened, and the total flow rate of the blown air that has passed through the air-side evaporator 14 is determined to pass through the heater core 22.

[0112] As a result, heat is dissipated from the coolant in the high-temperature coolant circuit 20 to the air blown into the vehicle cabin by the heater core 22. Therefore, the air cooled and dehumidified by the air-side evaporator 14 is heated by the heater core 22 and blown out into the vehicle cabin.

[0113] At this time, since the first three-way valve 26 closes the radiator flow path 20c, the coolant in the high-temperature coolant circuit 20 does not circulate to the common radiator 45. Therefore, heat is not dissipated from the coolant in the common radiator 45 to the outside air.

[0114] In the dehumidification heating mode, the coolant in the low-temperature coolant circuit 30 circulates through the common radiator 45, and heat is absorbed by the coolant in the low-temperature coolant circuit 30 from the outside air in the common radiator 45.

[0115] In this way, in the dehumidifying heating mode, the heat of the high-pressure refrigerant discharged from the compressor 11 is dissipated to the coolant in the high-temperature coolant circuit 20 by the condenser 12, the heat of the coolant in the high-temperature coolant circuit 20 is dissipated to the air by the heater core 22, and the air heated by the heater core 22 can be blown into the vehicle interior.

[0116] The air cooled and dehumidified by the air-side evaporator 14 is heated in the heater core 22. This makes it possible to realize dehumidification and heating of the vehicle interior.

[0117] In the heat storage circuit 80 in the dehumidifying and heating mode, the cooling water circulates through the waste heat device 82, and the waste heat of the waste heat device 82 is stored in the cooling water.

[0118] (3) Heating mode In the heating mode, the control device 60 operates the compressor 11, the high-temperature side pump 21, the low-temperature side pump 31, and the heat storage pump 81. In the heating mode, the control device 60 closes the first expansion valve 13 and opens the second expansion valve 16 at a throttled opening. In the heating mode, the control device 60 controls the first three-way valve 26 to open the heater core flow path 20b and close the radiator flow path 20c, and controls the second three-way valve 83 to close the defrost flow path 80b and open the circulation flow path 80c.

[0119] In the refrigeration cycle apparatus 10 in the heating mode, the refrigerant flows as follows. That is, in the refrigeration cycle apparatus 10, the refrigerant flowing out from the condenser 12 flows into the second expansion valve 16, where it is reduced in pressure and expanded to become a low-pressure refrigerant. The low-pressure refrigerant reduced in pressure by the second expansion valve 16 flows into the coolant-side evaporator 17, where it absorbs heat from the coolant in the low-temperature coolant circuit 30 and evaporates. As a result, the coolant in the low-temperature coolant circuit 30 is cooled.

[0120] At this time, since the first expansion valve 13 is closed, the refrigerant does not flow to the air-side evaporator 14. Therefore, the air is not cooled and dehumidified in the air-side evaporator 14.

[0121] In the heating mode, the high-temperature coolant circuit 20 circulates coolant between the condenser 12 and the heater core 22. Common Radiator 45 No cooling water circulates in the

[0122] The control signal output to the servo motor of the air mix door 54 is as follows: H The air passage of the heater core 22 is fully opened, and the total flow rate of the blown air that has passed through the air-side evaporator 14 is determined to pass through the heater core 22.

[0123] As a result, heat is dissipated from the coolant in the high-temperature coolant circuit 20 to the air blown into the vehicle cabin by the heater core 22. Therefore, the air that has passed through the air-side evaporator 14 (i.e., the air that has not been cooled and dehumidified by the air-side evaporator 14) is heated by the heater core 22 and blown out into the vehicle cabin.

[0124] At this time, since the first three-way valve 26 closes the radiator flow path 20c, the coolant in the high-temperature coolant circuit 20 does not circulate to the common radiator 45. Therefore, heat is not dissipated from the coolant in the common radiator 45 to the outside air.

[0125] In the heating mode, the coolant in the low-temperature coolant circuit 30 circulates through the common radiator 45, and heat is absorbed from the outside air by the coolant in the low-temperature coolant circuit 30 in the common radiator 45.

[0126] In this way, in the heating mode, the heat of the high-pressure refrigerant discharged from the compressor 11 is dissipated to the coolant in the high-temperature coolant circuit 20 by the condenser 12, the heat of the coolant in the high-temperature coolant circuit 20 is dissipated to the air by the heater core 22, and the air heated by the heater core 22 can be blown into the vehicle interior.

[0127] The heater core 22 heats the air that has passed through the air-side evaporator 14 without being cooled and dehumidified by the air-side evaporator 14. This makes it possible to heat the vehicle interior.

[0128] In the heat storage circuit 80 in the heating mode, the cooling water circulates through the waste heat device 82, and the waste heat of the waste heat device 82 is stored in the cooling water.

[0129] (4) Defrost mode The defrost mode defrosts the common radiator 45 after the dehumidifying heating mode or the heating mode. In the dehumidifying heating mode or the heating mode, the coolant in the low-temperature coolant circuit 30 absorbs heat from the outside air in the common radiator 45, so that when the temperature of the common radiator 45 falls below freezing, frost forms on the common radiator 45. Therefore, when frost forms on the common radiator 45, the defrost mode is executed to defrost the common radiator 45.

[0130] The defrosting mode includes a waste heat defrosting mode and a heating heat defrosting mode. In the waste heat defrosting mode, the common radiator 45 is defrosted by utilizing the waste heat of the waste heat device 82. In the heating defrosting mode, the common radiator 45 is defrosted by utilizing the heat generated for heating.

[0131] (4-1) Waste heat defrost mode In the waste heat defrost mode, the control device 60 operates the heat storage pump 81 and stops the compressor 11, the low-temperature side pump 31, the exterior blower 40, and the interior blower 53. In the dehumidification heating mode, the control device 60 controls the first three-way valve 26 to open the heater core flow path 20b and close the radiator flow path 20c, and controls the second three-way valve 83 to open the defrost flow path 80b and close the circulation flow path 80c.

[0132] Since the compressor 11 is stopped, the refrigerant does not flow through the refrigeration cycle device 10 in the defrost mode. Since the low-temperature side pump 31 is stopped, the coolant does not circulate through the low-temperature coolant circuit 30 in the defrost mode.

[0133] In the heat storage circuit 80 in the waste heat defrost mode, the coolant of the heat storage circuit 80 circulates between the waste heat device 82 and the common radiator 45, as indicated by the thick solid line in FIG.

[0134] Specifically, the cooling water discharged from the heat storage pump 81 passes through the waste heat equipment 82, flows through the common radiator 45, and is sucked into the high-temperature side pump 21. As a result, the high-temperature cooling water heated by the waste heat equipment 82 flows into the common radiator 45.

[0135] Since the exterior blower 40 is stopped, no air flows through the common radiator 45. Therefore, in the common radiator 45, the coolant is not cooled by the outside air.

[0136] In this manner, the heat of the cooling water in the heat storage circuit 80 flowing through the common radiator 45 can melt the frost that has adhered to the surface of the common radiator 45. That is, the waste heat of the waste heat device 82 can be effectively used for defrosting.

[0137] (4-2) Heating defrost mode In the heating heat defrost mode, the control device 60 operates the high-temperature side pump 21 and the heat storage pump 81, and stops the compressor 11, the low-temperature side pump 31, the exterior blower 40, and the interior blower 53. In the dehumidification heating mode, the control device 60 controls the first three-way valve 26 to open both the heater core flow path 20b and the radiator flow path 20c, and controls the second three-way valve 83 to close the defrost flow path 80b and open the circulation flow path 80c.

[0138] Since the compressor 11 is stopped, the refrigerant does not flow through the refrigeration cycle device 10 in the defrost mode. Since the low-temperature side pump 31 is stopped, the coolant does not circulate through the low-temperature coolant circuit 30 in the defrost mode.

[0139] In the heating heat defrost mode, the coolant in the high-temperature coolant circuit 20 circulates between the condenser 12, the heater core 22, the electric heater 25, and the common radiator 45, as shown by the thick solid line in FIG.

[0140] Specifically, the cooling water discharged from the high-temperature side pump 21 passes through the condenser 12, branches at branching point 20d to the heater core 22 side and the common radiator 45 side, flows in parallel through the heater core 22, the electric heater 25, and the common radiator 45, joins at joining point 20e, and is sucked into the high-temperature side pump 21. As a result, the high-temperature cooling water in the condenser 12 flows into the common radiator 45.

[0141] Since the interior blower 53 is stopped, no air flows through the heater core 22. Therefore, the high-temperature coolant in the heater core 22 flows into the common radiator 45 without being cooled by air.

[0142] Since the exterior blower 40 is stopped, no air flows through the common radiator 45. Therefore, in the common radiator 45, the coolant is not cooled by the outside air.

[0143] In this manner, the heat of the coolant in the high-temperature coolant circuit 20 flowing through the common radiator 45 can melt the frost that has formed on the surface of the common radiator 45 .

[0144] The cooling water cooled in the common radiator 45 merges with the cooling water flowing out from the heater core 22 at a junction 20 e and then flows into the condenser 12 .

[0145] By circulating the cooling water in this manner, the heat of the cooling water heated in the condenser 12 can be effectively used for defrosting. When the heat of the cooling water heated in the condenser 12 is insufficient for the heat required for defrosting, the heat generated by the electric heater 25 can be used for defrosting.

[0146] In the heat storage circuit 80 in the heating heat defrost mode, as indicated by the thick solid line in FIG. 4, the coolant circulates through the waste heat device 82, and the waste heat of the waste heat device 82 is stored in the coolant.

[0147] The control device 60 executes a control process shown in the flowchart of FIG. 5 to switch between the waste heat defrost mode and the heating heat defrost mode.

[0148] In step S100, it is determined whether the ignition switch (i.e., the start switch of the vehicle system) is ON and the air conditioning is ON. For example, if the auto switch or the air conditioner switch of the operation panel 70 is ON, it is determined that the air conditioning is ON.

[0149] If it is determined in step S100 that the ignition switch is ON and the air conditioning is ON, the process proceeds to step S110. If it is not determined in step S100 that the ignition switch is ON and the air conditioning is ON, the process proceeds to step S200.

[0150] In step S110, it is determined whether or not the common radiator 45 is frosted and the temperature TWW of the coolant in the heat storage circuit 80 is higher than the waste heat defrosting temperature α1. For example, whether or not the common radiator 45 is frosted is determined based on the temperature TWR of the coolant flowing into the common radiator 45 and the outside air temperature Tam using the control characteristic diagram shown in FIG.

[0151] That is, when the difference between the outside air temperature Tam and the temperature TWR of the coolant flowing into the common radiator 45 is large, it is determined that the common radiator 45 is frosted. When the common radiator 45 is frosted, the performance of the common radiator 45 decreases, so the control device 60 increases the rotation speed of the compressor 11 to reduce the low pressure of the cycle in order to ensure the required amount of heat absorption. When the low pressure of the cycle decreases, the temperature of the coolant cooled by the coolant-side evaporator 17 (i.e., the temperature TWR of the coolant flowing into the common radiator 45) decreases. Therefore, when the difference between the outside air temperature Tam and the temperature TWR of the coolant flowing into the common radiator 45 is large, it can be estimated that the common radiator 45 is frosted.

[0152] The waste heat defrosting temperature α1 is a coolant temperature (predetermined temperature) that can melt the frost adhering to the surface of the common radiator 45, and is stored in the control device 60 in advance.

[0153] If it is not determined in step S110 that the common radiator 45 is frosted and that the temperature TWW of the coolant in the heat storage circuit 80 is higher than the waste heat defrosting temperature α1, the process proceeds to step S120. If it is determined in step S110 that the common radiator 45 is frosted and that the temperature TWW of the coolant in the heat storage circuit 80 is higher than the waste heat defrosting temperature α1, the process proceeds to step S130.

[0154] In step S120, it is determined whether or not the common radiator 45 is frosted and the ignition switch is OFF. If it is determined in step S120 that the common radiator 45 is frosted and the ignition switch is OFF, the process proceeds to step S130. If it is not determined in step S120 that the common radiator 45 is frosted and the ignition switch is OFF, the process returns to step S100.

[0155] In step S130, the mode is switched to the waste heat defrosting mode, and the process proceeds to step S140.

[0156] In step S140, it is determined whether or not frost has formed on the common radiator 45 and the temperature TWH of the coolant in the high-temperature coolant circuit 20 is higher than the heating heat defrost temperature α2. The heating heat defrost temperature α2 is a coolant temperature (predetermined temperature) that can melt the frost on the surface of the common radiator 45, and is stored in advance in the control device 60.

[0157] If it is not determined in step S140 that the common radiator 45 is frosted and that the coolant temperature TWH of the high-temperature coolant circuit 20 is higher than the heating heat defrost temperature α2, the process proceeds to step S150. If it is determined in step S140 that the common radiator 45 is frosted and that the coolant temperature TWH of the high-temperature coolant circuit 20 is higher than the heating heat defrost temperature α2, the process proceeds to step S160.

[0158] In step S150, it is determined whether the common radiator 45 is frosted and the ignition switch is OFF. If it is determined in step S150 that the common radiator 45 is frosted and the ignition switch is OFF, the process proceeds to step S160. If it is not determined in step S150 that the common radiator 45 is frosted and the ignition switch is OFF, the process returns to step S100. In step S160, the process switches to the heating heat defrost mode and returns to step S100.

[0159] In step S200, it is determined whether pre-air conditioning is ON. Pre-air conditioning is an air conditioning operation that is started before an occupant gets into the vehicle (in other words, when the ignition switch is OFF). Pre-air conditioning is executed when an occupant uses the operation panel 70 or a remote control terminal to store the target temperature Tset in the vehicle cabin, the pre-air conditioning start time, etc. in the control device 60.

[0160] If it is determined in step S200 that the pre-AC is ON, the process proceeds to step S210. If it is not determined in step S200 that the pre-AC is ON, the process returns to step S100.

[0161] In step S210, it is determined whether the common radiator 45 is frosted and the temperature TWW of the coolant in the heat storage circuit 80 is higher than the waste heat defrosting temperature α1. For example, the temperature TWR of the coolant flowing into the common radiator 45 is compared with the outside air temperature Tam to determine whether the common radiator 45 is frosted.

[0162] If it is not determined in step S210 that the common radiator 45 is frosted and that the temperature TWW of the coolant in the heat storage circuit 80 is higher than the waste heat defrosting temperature α1, the process proceeds to step S220. If it is determined in step S210 that the common radiator 45 is frosted and that the temperature TWW of the coolant in the heat storage circuit 80 is higher than the waste heat defrosting temperature α1, the process proceeds to step S230.

[0163] In step S220, it is determined whether the common radiator 45 is frosted and the pre-air conditioning is turned off. If it is determined in step S220 that the common radiator 45 is frosted and the pre-air conditioning is turned off, the process proceeds to step S230. If it is not determined in step S120 that the common radiator 45 is frosted and the pre-air conditioning is turned off, the process returns to step S100.

[0164] In step S230, the mode is switched to the waste heat defrosting mode, and the process proceeds to step S240.

[0165] In step S240, it is determined whether or not frost has formed on the common radiator 45 and the temperature TWH of the coolant in the high-temperature coolant circuit 20 is higher than the heating heat defrost temperature α2.

[0166] If it is not determined in step S240 that the common radiator 45 is frosted and that the coolant temperature TWH of the high-temperature coolant circuit 20 is higher than the heating heat defrost temperature α2, the process proceeds to step S250. If it is determined in step S240 that the common radiator 45 is frosted and that the coolant temperature TWH of the high-temperature coolant circuit 20 is higher than the heating heat defrost temperature α2, the process proceeds to step S260.

[0167] In step S250, it is determined whether the common radiator 45 is frosted and the pre-air conditioning is turned off. If it is determined in step S250 that the common radiator 45 is frosted and the pre-air conditioning is turned off, the process proceeds to step S260. If it is not determined in step S250 that the common radiator 45 is frosted and the pre-air conditioning is turned off, the process returns to step S100. In step S260, the process switches to the heating heat defrost mode and returns to step S100.

[0168] Fig. 7 is a time chart showing an example of the control result of this embodiment. Fig. 7 shows the time transition of the coefficient of performance (so-called COP) or performance of the refrigeration cycle device 10 when the waste heat defrosting mode is executed during driving, when stopped, and during pre-air conditioning. The coefficient of performance or performance decreases as frost progresses on the common radiator 45, but the common radiator 45 is defrosted by executing the waste heat defrosting mode, and the coefficient of performance or performance is restored.

[0169] 8 shows the time transition of the coefficient of performance (so-called COP) or performance of the refrigeration cycle apparatus 10 when the waste heat defrost mode is switched to the heating heat defrost mode. Even if the waste heat defrost mode cannot completely defrost, the heating heat defrost mode can continue the defrosting, so that the coefficient of performance or performance can be restored to a high level compared to the case where only the waste heat defrost mode is executed.

[0170] In this embodiment, the control device 60 determines whether or not defrosting of the common radiator 45 is necessary. If it is determined that defrosting of the common radiator 45 is not necessary, the control device 60 circulates coolant separately in the heat storage circuit 80, the high-temperature coolant circuit 20, and the low-temperature coolant circuit 30. If it is determined that defrosting of the common radiator 45 is necessary, the control device 60 controls the first three-way valve 26 or the second three-way valve to circulate the coolant in the heat storage circuit 80 or the high-temperature coolant circuit 20 to the common radiator 45.

[0171] According to this, since defrosting of the common radiator 45 can be reliably performed when defrosting is necessary, defrosting can be performed efficiently.

[0172] In this embodiment, in the heat storage circuit 80, the coolant circulates through the waste heat device 82, so that the waste heat from the waste heat device 82 is stored in the coolant. This allows the waste heat to be effectively used for defrosting, so that defrosting can be performed with reduced energy.

[0173] In this embodiment, when the control device 60 determines that defrosting of the common radiator 45 is necessary, it controls the first three-way valve 26 or the second three-way valve so that the coolant in the high-temperature coolant circuit 20 flows in parallel to the heater core 22 and the common radiator 45.

[0174] According to this, a part of the heating heat can be used for defrosting, so that defrosting can be performed reliably.

[0175] In this embodiment, when the control device 60 determines that defrosting of the common radiator 45 is necessary, the control device 60 controls the first three-way valve 26 or the second three-way valve to circulate the coolant in the heat storage circuit 80 to the common radiator 45. When the control device 60 determines that defrosting of the common radiator 45 is necessary after circulating the coolant in the heat storage circuit 80 to the common radiator 45, the control device 60 controls the first three-way valve 26 or the second three-way valve to cause the coolant in the high-temperature coolant circuit 20 to flow in parallel to the heater core 22 and the common radiator 45.

[0176] According to this, when the waste heat is not enough to completely defrost the frost, the heating heat is used to defrost the frost, so that the defrosting can be performed reliably and in an energy-saving manner.

[0177] In this embodiment, when the vehicle is running, the control device 60 detects that the common radiator 45 is in a frosted state and the temperature TWW of the coolant in the heat storage circuit 80 is higher than the waste heat defrost temperature α1 or the temperature TWH of the coolant in the high temperature coolant circuit 20 is higher than the heating heat defrost temperature α2. case , it is determined that defrosting of the common radiator 45 is necessary.

[0178] This makes it possible to appropriately determine whether defrosting of the common radiator 45 is necessary, thereby enabling efficient defrosting.

[0179] In this embodiment, when pre-air conditioning is being performed, the control device 60 detects whether the common radiator 45 is in a frosted state and whether the temperature TWW of the coolant in the heat storage circuit 80 is higher than the waste heat defrost temperature α1 or whether the temperature TWH of the coolant in the high temperature coolant circuit 20 is higher than the heating heat defrost temperature α2. case Therefore, it is determined that defrosting of the common radiator 45 is necessary. This allows defrosting to be performed without impairing the comfort of the air conditioning for the passengers as much as possible.

[0180] In this embodiment, when the vehicle changes from a traveling state to a stopped state and the common radiator 45 is in a frosted state, the control device 60 determines that defrosting of the common radiator 45 is necessary.

[0181] This allows the remaining heat generated while the vehicle is running to be effectively utilized for defrosting, thereby enabling defrosting to be performed with reduced energy consumption.

[0182] In this embodiment, when the pre-air conditioning is completed and the common radiator 45 is in a frosted state, the control device 60 determines that the common radiator 45 needs to be defrosted.

[0183] This allows defrosting to be performed effectively using the remaining heat generated during air conditioning before the occupants enter the vehicle, thereby enabling defrosting to be performed with reduced energy consumption.

[0184] In this embodiment, the control device 60 determines whether the common radiator 45 is in a frosted state based on the temperature TWR of the coolant flowing through the common radiator 45 and the temperature Tam of the outside air. This allows the frosted state to be accurately determined with simple control.

[0185] Second embodiment In the above-described first embodiment, the radiator flow path 20c of the high-temperature coolant circuit 20, the low-temperature coolant circuit 30, and the defrost flow path 80b of the heat storage circuit 80 are joined together, and a common radiator 45 is disposed at this joining portion. In this embodiment, as shown in Fig. 9, the radiator flow path 20c of the high-temperature coolant circuit 20 does not join together with the low-temperature coolant circuit 30 and the defrost flow path 80b of the heat storage circuit 80, and the common radiator 45 has a high-temperature side radiator 23 disposed in the radiator flow path 20c of the high-temperature coolant circuit 20, and a low-temperature side radiator 32 disposed at the joining portion of the low-temperature coolant circuit 30 and the defrost flow path 80b.

[0186] The low-temperature side radiator 32 is a first heat medium flowing portion of the common radiator 45, and the high-temperature side radiator 23 is a second heat medium flowing portion of the common radiator 45.

[0187] The high-temperature side radiator 23 is a radiator that exchanges heat between the coolant in the high-temperature coolant circuit 20 and outside air, thereby dissipating heat from the coolant to the outside air. The low-temperature side radiator 32 is an outside air heat absorption section that exchanges heat between the coolant in the low-temperature coolant circuit 30 and outside air, thereby causing the coolant in the low-temperature coolant circuit 30 to absorb heat from the outside air. The high-temperature side radiator 23 and the low-temperature side radiator 32 are joined to each other by common fins 37.

[0188] The common fin 37 is a heat exchange promoting member that promotes heat exchange between the coolant and the air. The common fin 37 is a member made of metal (for example, aluminum). The common fin 37 is a joint that transfers heat from the high-temperature side radiator 23 to the low-temperature side radiator 32 by joining the high-temperature side radiator 23 and the low-temperature side radiator 32 with metal. The common fin 37 is a heat transfer member that connects the high-temperature side radiator 23 and the low-temperature side radiator 32 to enable heat transfer.

[0189] The high temperature side radiator 23 and the low temperature side radiator 32 are disposed in series in this order in the direction of the flow of outside air. Outside air is blown to the high temperature side radiator 23 and the low temperature side radiator 32 by an exterior blower 40.

[0190] In the cooling mode, the control device 60 controls the first three-way valve 26 so that both the heater core flow path 20b and the radiator flow path 20c are open. As a result, in the cooling mode, the coolant in the high-temperature coolant circuit 20 circulates through the high-temperature side radiator 23, and heat is dissipated from the coolant in the high-temperature side radiator 23 to the outside air.

[0191] In the dehumidifying and heating mode, the control device 60 controls the first three-way valve 26 so that the heater core flow path 20b is opened and the radiator flow path 20c is closed. As a result, in the dehumidifying and heating mode, the coolant in the low-temperature coolant circuit 30 in the low-temperature side radiator 32 absorbs heat from the outside air.

[0192] In the heating mode, the control device 60 controls the first three-way valve 26 so that the heater core flow path 20b is opened and the radiator flow path 20c is closed. As a result, in the heating mode, the coolant in the low-temperature coolant circuit 30 absorbs heat from the outside air in the low-temperature side radiator 32.

[0193] In the waste heat defrosting mode, the control device 60 stops the low-temperature side pump 31, and controls the second three-way valve 83 so that the coolant in the waste heat equipment flow path 80a of the heat storage circuit 80 flows to the low-temperature side radiator 32. This allows the heat of the coolant in the heat storage circuit 80 flowing through the low-temperature side radiator 32 to melt the frost that has adhered to the surface of the low-temperature side radiator 32.

[0194] In the heating heat defrost mode, the control device 60 stops the low-temperature side pump 31 and controls the first three-way valve 26 so that the coolant in the radiator flow path 20c of the high-temperature coolant circuit 20 flows to the high-temperature side radiator 23, as shown by the thick arrow in Figure 10.

[0195] The high-temperature side radiator 23 and the low-temperature side radiator 32 are connected to each other by common fins 37 so that heat can be transferred between them, and therefore the heat of the coolant in the high-temperature coolant circuit 20 flowing through the high-temperature side radiator 23 is transferred to the low-temperature side radiator 32 via the fins 37.

[0196] The heat supplied to low-temperature side radiator 32 in this manner can melt the frost adhering to the surface of low-temperature side radiator 32 .

[0197] In this embodiment, the common radiator 45 has a low-temperature side radiator 32 through which coolant cooled in the coolant side evaporator 17 flows, a high-temperature side radiator 23 through which coolant heated by the electric heater 25 flows, and fins 37 that connect the low-temperature side radiator 32 and the high-temperature side radiator 23 to enable thermal transfer.

[0198] This allows defrosting without mixing the cooling water cooled by the cooling water side evaporator 17 and the cooling water heated by the electric heater 25, making it possible to efficiently manage cooling waters of different temperature ranges.

[0199] Third embodiment In the above-described embodiments, if complete defrosting cannot be achieved in the waste heat defrost mode, the defrosting capacity is improved by switching from the waste heat defrost mode to the heating heat defrost mode. However, in the present embodiment, as shown in FIG. 11, defrosting is performed only in the heating heat defrost mode without executing the waste heat defrost mode.

[0200] The flowchart of this embodiment shown in FIG. 11 is obtained by deleting the steps related to the waste heat heating mode from the flowchart of the first embodiment shown in FIG.

[0201] 12 shows the time transition of the coefficient of performance (COP) or performance of the refrigeration cycle device 10 when the heating heat defrost mode is executed while the vehicle is running, while the vehicle is stopped, and during pre-air conditioning. The coefficient of performance or performance temporarily decreases because part of the heating heat is used for defrosting instead of heating, but the coefficient of performance or performance is restored by defrosting the common radiator 45.

[0202] (Other embodiments) The above-described embodiments can be combined as appropriate. The above-described embodiments can be modified in various ways, for example, as follows.

[0203] (1) In the above embodiment, cooling water is used as the heat medium, but various media such as oil may be used as the heat medium. Nanofluid may be used as the heat medium. Nanofluid is a fluid that contains nanoparticles with a particle size on the order of nanometers.

[0204] (2) In the refrigeration cycle apparatus 10 of the above embodiment, a fluorocarbon-based refrigerant is used as the refrigerant. However, the type of refrigerant is not limited to this, and natural refrigerants such as carbon dioxide or hydrocarbon-based refrigerants may also be used.

[0205] Furthermore, the refrigeration cycle device 10 of the above embodiment constitutes a subcritical refrigeration cycle in which the high-pressure side refrigerant pressure does not exceed the critical pressure of the refrigerant, but it may also constitute a supercritical refrigeration cycle in which the high-pressure side refrigerant pressure exceeds the critical pressure of the refrigerant.

[0206] (3) The above 2 In the embodiment, the high-temperature side radiator 23 and the low-temperature side radiator 32 are separate radiators, and the high-temperature side radiator 23 and the low-temperature side radiator 32 are joined to each other by a common fin 37, but the high-temperature side radiator 23 and the low-temperature side radiator 32 may also be configured as a single radiator.

[0207] For example, the cooling water tank of the high-temperature side radiator 23 and the cooling water tank of the low-temperature side radiator 32 may be integrated with each other, so that the high-temperature side radiator 23 and the low-temperature side radiator 32 are configured as a single radiator.

[0208] (4) In the above embodiment, the electric heater 25 is disposed downstream of the branch portion 20d of the high-temperature coolant circuit 20 and upstream of the heater core 22, but the position of the electric heater 25 in the high-temperature coolant circuit 20 is not limited to this.

[0209] For example, the electric heater 25 may be disposed downstream of the condenser 12 of the high-temperature coolant circuit 20 and upstream of the branching portion 20d. In this case, in the heating heat defrost mode, the first three-way valve 26 may close the heater core flow path 20b to stop the flow of coolant through the heater core flow path 20b. [Explanation of symbols]

[0210] 11 Compressor 12 Condenser (heat dissipation section) 16 Second expansion valve (pressure reducing section) 17 Cooling water side evaporator (evaporation section) 20 High temperature cooling water circuit (first circulation circuit, heating circuit) 25 Electric heater (heat source, second heat source) 26 First three-way valve (flow path switching section) 30 Low temperature cooling water circuit (second circulation circuit) 45 Common radiator (outside air heat intake section) 60 Control device (flow path switching unit) 80 Heat storage circuit (first circulation circuit, heat storage circuit) 82 Waste heat equipment (heat source, first heat source) 83 Second three-way valve (flow path switching section)

Claims

1. A compressor (11) that draws in, compresses, and discharges a refrigerant; a heat dissipation section (12) that dissipates heat from the refrigerant discharged from the compressor; a pressure reducing section (16) for reducing the pressure of the refrigerant whose heat has been radiated in the heat radiating section; an evaporation section (17) that exchanges heat between the refrigerant decompressed in the decompression section and a heat medium to evaporate the refrigerant and cool the heat medium; an outside air heat absorption section (45) for absorbing heat from outside air into the heat medium cooled in the evaporator section; A heat source (25, 82) that radiates heat to the heat medium to heat the heat medium; a first circulation circuit (20, 80) for circulating the heat medium through the heat source; a second circulation circuit (30) for circulating the heat medium between the evaporator and the outside air heat absorbing section; Determining whether defrosting of the outside air heat absorption section is necessary; When it is determined that defrosting of the outdoor air heat absorption section is not necessary, the heat medium is circulated in the first circulation circuit and the second circulation circuit separately, a flow path switching unit (26, 60, 83) that switches a flow path of the heat medium so that the heat medium in the first circulation circuit is circulated to the outside air heat absorption unit when it is determined that defrosting of the outside air heat absorption unit is necessary; an air heating section (22) that heats the air by dissipating heat of the heat medium into air blown into the vehicle compartment, The heat dissipation unit dissipates heat of the refrigerant discharged from the compressor to the heat medium, The heat source includes a first heat source (82) that dissipates waste heat generated during operation to the heat medium, and a second heat source (25) that generates heat for heating the air, the first circulation circuit includes a heat storage circuit (80) in which the heat medium circulates through the first heat source to store waste heat of the first heat source in the heat medium, and a heating circuit (20) that circulates the heat medium through the heat dissipation section, the second heat source, and the air heating section; When the flow path switching unit determines that defrosting of the outdoor air heat absorption unit is necessary, it switches the flow path of the heat medium so that the heat medium in the heat storage circuit circulates to the outdoor air heat absorption unit without circulating to the second heat source and the air heating unit, and when it determines that defrosting of the outdoor air heat absorption unit is necessary after circulating the heat medium in the heat storage circuit to the outdoor air heat absorption unit, it switches the flow path of the heat medium so that the heat medium in the heating circuit flows in parallel to the air heating unit and the outdoor air heat absorption unit without circulating to the first heat source.

2. The refrigeration cycle device according to claim 1, wherein the flow path switching unit determines that defrosting of the outside air heat absorption unit is necessary when the outside air heat absorption unit is in a frosted state and the temperature (TWW, TWH) of the heat medium in the first circulation circuit exceeds a predetermined temperature (α1, α2) while the vehicle is running.

3. The refrigeration cycle device according to claim 1 or 2, wherein the flow path switching unit determines that defrosting of the outside air heat absorption unit is necessary when air conditioning is being performed before an occupant gets into the vehicle, when the outside air heat absorption unit is in a frosted state and when the temperature (TWW, TWH) of the heat medium in the first circulation circuit exceeds a predetermined temperature (α1, α2).

4. The refrigeration cycle device according to any one of claims 1 to 3, wherein the flow path switching unit determines that defrosting of the outside air heat absorption unit is necessary when the vehicle changes from a running state to a stopped state and the outside air heat absorption unit is in a frosted state.

5. The refrigeration cycle device according to any one of claims 1 to 4, wherein the flow path switching unit determines that defrosting of the outside air heat absorption unit is necessary when the outside air heat absorption unit is in a frosted state when air conditioning is terminated before an occupant gets into the vehicle.

6. The refrigeration cycle device according to any one of claims 2 to 5, wherein the flow path switching unit determines whether the outdoor air heat absorption unit is in a frosted state based on a temperature (TWR) of the heat medium flowing through the outdoor air heat absorption unit and a temperature (Tam) of the outdoor air.

7. 7. The refrigeration cycle device according to claim 1, wherein the outside air heat absorption section has a first heat medium circulating section (32) through which the heat medium cooled in the evaporator section flows, a second heat medium circulating section (23) through which the heat medium heated by the heat source flows, and a heat transfer member (37) connecting the first heat medium circulating section and the second heat medium circulating section so as to be capable of transferring heat.

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