WO2022239602A1

WO2022239602A1 - Air-conditioning device for vehicle

Info

Publication number: WO2022239602A1
Application number: PCT/JP2022/017977
Authority: WO
Inventors: 幸久伊集院; 紘明河野; 康弘横尾; 好則一志; 芳生林; 順基平山; 騎士武藤; 吉毅加藤
Original assignee: 株式会社デンソー
Priority date: 2021-05-14
Filing date: 2022-04-18
Publication date: 2022-11-17
Also published as: JP2022175756A

Abstract

This air-conditioning device for a vehicle comprises: a heat medium circuit (30) in which a heat medium circulates; a plurality of heat sinks (36, 37) which are disposed in the heat medium circuit and from which heat is absorbed by the heat medium; a switching unit (33) for switching whether or not the heat medium absorbs heat from the plurality of heat sinks; a compressor (11) that draws in, compresses, and discharges a refrigerant; a heat radiation section (12) that causes the refrigerant discharged from the compressor to radiate heat into air blown into an air-conditioned space; a decompression section (16) that decompresses the refrigerant caused to radiate heat in the heat radiation section; an evaporator (17) that causes the refrigerant decompressed in the decompression section to be evaporated by absorbed heat from the heat medium; and a control unit (60) that determines which of the plurality of heat sinks to use to cause the heat medium to absorb heat on the basis of the temperatures and heating values of the plurality of heat sinks, and controls the switching unit.

Description

vehicle air conditioner

Cross-reference to related applications

This application is based on Japanese Patent Application No. 2021-82431 filed on May 14, 2021, and the contents thereof are incorporated herein.

The present disclosure relates to a vehicle air conditioner that absorbs heat from a plurality of heat absorption sources to heat air.

Conventionally, Patent Document 1 describes a vehicle air conditioning system in which a ventilation exhaust heat recovery device, a motor/battery, and an electric heater are connected as heat sources to the coolant of the coolant cycle.

By allowing the coolant heated by these heat sources to absorb heat in the refrigerant/coolant heat exchanger, the air is heated by the second refrigerant condenser and used for heating.

In this prior art, which of the heat sources the coolant should absorb heat from is selected based on the temperature of the coolant near each heat source.

Japanese Patent No. 5297154

However, in the above conventional technology, the heat source is selected based only on the temperature of the coolant. Therefore, the temperature fluctuation behavior of the coolant differs depending on whether the amount of heat generated by each heat source is large or small. There is concern that frequent switching of heat sources may adversely affect the air conditioning performance and durability of each heat source.

In view of the above points, the present disclosure aims to suppress frequent switching of endotherms.

A vehicle air conditioner according to one aspect of the present disclosure includes a heat medium circuit, a plurality of heat absorption sources, a switching section, a compressor, a heat dissipation section, a pressure reduction section, an evaporator, and a control section. A heat medium circulates in the heat medium circuit. A plurality of heat absorption sources are arranged in the heat medium circuit, and heat is absorbed by the heat medium. The switching unit switches whether or not to allow the heat medium to absorb heat from the plurality of heat absorption sources.

The compressor sucks in the refrigerant, compresses it, and discharges it. The heat radiating section causes the refrigerant discharged from the compressor to radiate heat to the air blown into the air-conditioned space. The decompression part decompresses the refrigerant radiated by the heat radiation part. The evaporator evaporates the refrigerant decompressed by the decompression unit by absorbing heat from the heat medium. The control unit determines which one of the plurality of heat absorption sources is used to absorb heat by the heat medium based on the temperature and amount of heat generation of the plurality of heat absorption sources, and controls the switching unit.

According to this, the heat absorption is switched based on not only the temperature but also the calorific value, so the temperature fluctuation behavior can be stabilized, and the frequent occurrence of the heat absorption switching can be suppressed.

The above and other objects, features and advantages of the present disclosure will become more apparent from the following detailed description with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS It is the whole block diagram of the vehicle air conditioner of one Embodiment, and shows the operating state of cooling mode. It is a block diagram which shows the electric control part of the vehicle air conditioner of one Embodiment. BRIEF DESCRIPTION OF THE DRAWINGS It is the whole block diagram of the vehicle air conditioner of one Embodiment, and has shown the operating state of dehumidification heating mode. BRIEF DESCRIPTION OF THE DRAWINGS It is the whole block diagram of the vehicle air conditioner of one Embodiment, and shows the operating state in heating mode. 3 is a flow chart showing control processing executed by a control device for a vehicle air conditioner according to one embodiment; 4 is a time chart showing temperature changes of a heat absorption source in an operation example of the vehicle air conditioner of one embodiment; 4 is a time chart showing temperature changes of equipment, cooling water, and refrigerant in an operation example of the vehicle air conditioner of one embodiment.

An embodiment will be described below based on the drawings. A vehicle air conditioner 1 shown in FIG. 1 is an air conditioner that adjusts 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 .

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

The refrigerating cycle device 10 is a vapor compression refrigerator comprising 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. be. In the refrigerating cycle device 10 of the present embodiment, a freon-based refrigerant is used as a refrigerant, and a subcritical refrigerating cycle is constructed in which the pressure of the refrigerant on the high-pressure side does not exceed the critical pressure of the refrigerant.

The second expansion valve 16 and the cooling water 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.

A first refrigerant circuit and a second refrigerant 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 this order. In the second refrigerant circulation circuit, the refrigerant circulates through the compressor 11, the condenser 12, the second expansion valve 16, and the coolant-side evaporator 17 in this order.

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

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 radiating section that heats the cooling water by heat-exchanging the refrigerant discharged from the compressor 11 and the cooling water.

In the case of an electric vehicle, the compressor 11 and condenser 12 are arranged in the motor room of the vehicle. A motor room is a space in which an electric motor for traveling is accommodated. In the case of a hybrid vehicle, compressor 11 and condenser 12 are arranged in the engine room of the vehicle. An engine room is a space in which an engine is housed.

The condenser 12 has a condensation section 12a, a receiver 12b and a supercooling section 12c. In the condenser 12, the refrigerant flows through the condensing portion 12a, the receiver 12b and the supercooling portion 12c in that order.

The condensation section 12a condenses the high-pressure side refrigerant by exchanging 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 receiver 12b is a gas-liquid separation unit that separates the gas-liquid of the high-pressure refrigerant that has flowed out of the condenser 12, causes the separated liquid-phase refrigerant to flow downstream, and stores surplus refrigerant in the cycle. The supercooling unit 12c performs heat exchange between the liquid-phase refrigerant flowing out of the receiver 12b and the cooling water of the high-temperature cooling water circuit 20, thereby supercooling the liquid-phase refrigerant.

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

The first expansion valve 13 is a first decompression unit that decompresses and expands the liquid-phase refrigerant that has flowed out from the receiver 12b. The first expansion valve 13 is an electric expansion valve. An electric expansion valve is an electric variable throttle mechanism that includes a valve body that can change the opening degree of the throttle and an electric actuator that changes the opening degree of the valve body.

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

The first expansion valve 13 may be a mechanical thermal expansion valve. If the first expansion valve 13 is a mechanical thermal expansion valve, an on-off valve that opens and closes the refrigerant flow path on the first expansion valve 13 side must be provided separately from the first expansion valve 13 .

The air-side evaporator 14 is an evaporator that exchanges heat between the refrigerant flowing out of the first expansion valve 13 and the air blown into the vehicle interior to evaporate the refrigerant. In the air-side evaporator 14, the refrigerant absorbs heat from the air blown into the vehicle interior. The air-side evaporator 14 is an air cooler that cools the air blown into the vehicle interior.

The constant pressure valve 15 is a pressure adjusting unit that maintains the pressure of the refrigerant on 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, when the pressure of the refrigerant on the outlet side of the air-side evaporator 14 falls below a predetermined value, the constant pressure valve 15 reduces the passage area (that is, throttle opening) of the refrigerant passage, When the pressure of the refrigerant on the side exceeds a predetermined value, the passage area of the refrigerant passage (that is, throttle opening) is increased. The gas-phase refrigerant pressure-regulated by the constant pressure valve 15 is sucked into the compressor 11 and compressed.

In cases such as when there is little variation in the flow rate of the circulating refrigerant that circulates through the cycle, instead of the constant pressure valve 15, a fixed throttle made up of an orifice, capillary tube, or the like may be employed.

The second expansion valve 16 is a second decompression section that decompresses and expands the liquid-phase refrigerant that has flowed out of the condenser 12 . The second expansion valve 16 is an electric expansion valve. An electric expansion valve is an electric variable throttle mechanism that includes a valve body that can change the opening degree of the throttle and an electric actuator that changes the opening degree of the valve body. The second expansion valve 16 can fully close the refrigerant passage.

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

The second expansion valve 16 may be a mechanical thermal expansion valve. If the second expansion valve 16 is a mechanical thermal expansion valve, an on-off valve that opens and closes the refrigerant flow path on the side of the second expansion valve 16 must be provided separately from the second expansion valve 16 .

The cooling water side evaporator 17 is an evaporator that exchanges heat between the refrigerant flowing out of the second expansion valve 16 and the cooling water of the low-temperature cooling water circuit 30 to evaporate the refrigerant. 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 vapor phase refrigerant evaporated in the cooling water side evaporator 17 is sucked into the compressor 11 and compressed.

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

A condenser 12, a high temperature side pump 21, a heater core 22, a radiator 45, a first reserve tank 24, and an electric heater 25 are arranged in the high temperature cooling water circuit 20.

The high temperature side pump 21 is a heat medium pump that sucks 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.

The heater core 22 is an air heating unit that heats the air that is blown into the vehicle interior by exchanging heat between the cooling water of the high-temperature cooling water circuit 20 and the air that is blown into the vehicle interior. In the heater core 22, the cooling water radiates heat to the air blown into the vehicle interior. The heater core 22 is a heat utilization section that utilizes the heat of the cooling water heated by the condenser 12 . The high-temperature cooling water circuit 20 is a heating circuit that circulates cooling water to the heater core 22 .

The radiator 45 is a radiator that exchanges heat between the cooling water of the high-temperature cooling water circuit 20 and the outside air, and releases heat from the cooling water to the outside air. The radiator 45 is a common radiator for the high-temperature cooling water circuit 20 and the low-temperature cooling water circuit 30 .

The condenser 12 and the high temperature side pump 21 are arranged in the condenser channel 20a. The condenser channel 20a is a channel through which the cooling water of the high-temperature cooling water circuit 20 flows.

The direction of flow of cooling water in the condenser 12 is opposite to the direction of flow of refrigerant in the condenser 12 . That is, in the condenser 12, the cooling water flows through the supercooling section 12c and the condensing section 12a in that order.

The heater core 22 is arranged in the heater core channel 20b. The heater core channel 20b is a channel through which the cooling water of the high-temperature cooling water circuit 20 flows.

The radiator 45 is arranged in the radiator channel 20c. The radiator flow path 20 c is a flow path through which the cooling water of the high-temperature cooling water circuit 20 flows in parallel with the heater core 22 .

A first on-off valve 26a and a second on-off valve 26b are arranged in the branch portion 20d of the high-temperature cooling water circuit 20. The branching portion 20d is a branching portion that branches from the condenser flow path 20a into the heater core flow path 20b and the radiator flow path 20c.

The first on-off valve 26 a and the second on-off valve 26 b are flow path switching units that switch the cooling water flow path in the high-temperature cooling water circuit 20 . The first open/close valve 26a opens and closes the heater core flow path 20b. The first on-off valve 26a adjusts the opening degree of the heater core flow path 20b. The second on-off valve 26b opens and closes the radiator flow path 20c. The second on-off valve 26b adjusts the degree of opening of the radiator flow path 20c. The first on-off valve 26a and the second on-off valve 26b adjust the opening degree ratio between the heater core flow path 20b and the radiator flow path 20c. The first on-off valve 26 a and the second on-off valve 26 b adjust the flow rate ratio between the cooling water flowing through the heater core 22 and the cooling water flowing through the radiator 45 .

A first reserve tank 24 is arranged on the downstream side of the confluence portion 20 e of the high-temperature cooling water circuit 20 and the upstream side of the high-temperature side pump 21 . The confluence portion 20e is a confluence portion where the heater core flow path 20b and the radiator flow path 20c merge into the condenser flow path 20a.

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

The first reserve tank 24 is a closed reserve tank or an open-air reserve tank. The closed reserve tank is a reserve tank that sets the pressure of the liquid surface of the stored cooling water to a predetermined pressure. The atmosphere open type reserve tank is a reserve tank in which the pressure at the liquid surface of the stored cooling water is brought to the atmospheric pressure.

The first reserve tank 24 has a gas-liquid separation function that separates air bubbles mixed in the cooling water from the cooling water.

The electric heater 25 is arranged downstream of the condenser 12 and upstream of the branch portion 20d. The electric heater 25 is a heat source device that generates Joule heat when electric power is supplied from a battery to heat the cooling water. The electric heater 25 is the second heat source. The electric heater 25 supplementarily heats the cooling water in the high temperature cooling water circuit 20 . Electric heater 25 is controlled by controller 60 .

A low temperature side pump 31, a cooling water side evaporator 17, a radiator 45, and a second reserve tank 32 are arranged in the low temperature cooling water circuit 30. The low temperature side pump 31 is a heat medium pump that sucks and discharges cooling water. The low temperature side pump 31 is an electric pump.

A part of the flow path of the low-temperature cooling water circuit 30 is shared with the radiator flow path 20 c of the high-temperature cooling water circuit 20 . The radiator 45 is arranged in a portion of the low-temperature cooling water circuit 30 that is common to the radiator flow path 20 c of the high-temperature cooling water circuit 20 . Therefore, both the cooling water in the radiator flow path 20 c of the high-temperature cooling water circuit 20 and the cooling water in the low-temperature cooling water circuit 30 can flow through the radiator 45 .

The radiator 45 and the outdoor fan 40 are arranged at the front of the vehicle. Therefore, when the vehicle is running, the radiator 45 can be exposed to running wind.

The outdoor blower 40 is an outside air blower that blows outside air toward the radiator 45 . The outdoor blower 40 is an electric blower whose fan is driven by an electric motor. The operation of outdoor fan 40 is controlled by control device 60 .

The second reserve tank 32 is arranged downstream of the radiator 45 and upstream of the low temperature side pump 31 . The second reserve tank 32 has the same structure and function as the first reserve tank 24 .

The air-side evaporator 14 and heater core 22 are housed in the air conditioning casing 51 of the indoor air conditioning unit 50 . The indoor air conditioning unit 50 is arranged inside a not-shown instrument panel in the front part of the passenger compartment. The air conditioning casing 51 is an air passage forming member that forms an air passage.

The heater core 22 is arranged downstream of the air-side evaporator 14 in the air passage in the air conditioning casing 51 . An inside/outside air switching box 52 and an indoor fan 53 are arranged in the air conditioning casing 51 .

The inside/outside air switching box 52 is an inside/outside air switching unit that switches between introducing inside air and outside air into the air passage in the air conditioning casing 51 . The indoor air blower 53 draws in the inside air and the outside air introduced into the air passage in the air conditioning casing 51 through the inside/outside air switching box 52 and blows the air. The operation of the indoor fan 53 is controlled by the controller 60 .

An air mix door 54 is arranged 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 air volume ratio between the cold air flowing into the heater core 22 and the cold air flowing through the cold air bypass passage 55 among the cold air that has passed through the air-side evaporator 14 .

The cold air bypass passage 55 is an air passage through which cold air that has passed through the air-side evaporator 14 flows while bypassing the heater core 22 .

The air mix door 54 is a rotary door having a rotating shaft rotatably supported with respect to the air conditioning casing 51 and a door base plate portion coupled to the rotating shaft. By adjusting the opening position of the air mix door 54, the temperature of the air-conditioned air blown out from the air-conditioning casing 51 into the passenger compartment can be adjusted to a desired temperature.

The rotating shaft of the air mix door 54 is driven by a servomotor 56. The operation of the air mix door servomotor 56 is controlled by a control device 60 .

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-shaped door made of a rigid body. A film door formed of a flexible film material may be used.

The air-conditioned air whose temperature has been adjusted by the air mix door 54 is blown into the vehicle interior through an outlet 57 formed in the air-conditioning casing 51 .

The low-temperature cooling water circuit 30 has a four-way valve 33, a first heat absorption channel 34 and a second heat absorption channel 35. The four-way valve 33 is arranged on the outlet side of the coolant-side evaporator 17 and the inlet side of the radiator 45 in the low-temperature coolant circuit 30 . A first heat absorption channel 34 and a second heat absorption channel 35 are connected to the four-way valve 33 .

The four-way valve 33 is a channel switching unit that switches the cooling water channel in the low-temperature cooling water circuit 30 . The four-way valve 33 opens and closes the first heat absorption channel 34 and the second heat absorption channel 35 . The first heat absorption channel 34 and the second heat absorption channel 35 are arranged in parallel with the radiator 45 in the flow of cooling water in the low-temperature cooling water circuit 30 . The first heat absorption flow path 34 and the second heat absorption flow path 35 are arranged in parallel with each other in the flow of cooling water in the low-temperature cooling water circuit 30 .

A first heat absorption target device group 36 is arranged in the first heat absorption flow path 34 . A second heat absorption target device group 37 is arranged in the second heat absorption flow path 35 . Each device included in the first heat absorption target device group 36 and the second heat absorption target device group 37 is a heat generating device that generates heat as it operates, and is a heat absorption source that absorbs heat into the cooling water.

In this example, the first heat absorption target device group 36 is a battery 36a and a charger 36b, and the second heat absorption target device group 37 is a transaxle 37a, a motor generator 37b, and an inverter 37c.

The battery 36a supplies power for running to the electric motor for running. The battery 36a supplies power to the compressor 11 and various accessories. Charger 36b is used to charge battery 36a.

The transaxle 37a is a power transmission mechanism that integrates a transmission, a differential gear, and the like. The motor-generator 37b outputs driving force for running when supplied with electric power, and generates regenerative electric power during deceleration and the like. The inverter 37c converts the direct current supplied from the battery 36a into alternating current and outputs the alternating current to the motor generator 37b.

It is preferable that the first heat absorption target device group 36 is a device that has a narrower guaranteed temperature range and easily generates heat compared to the second heat absorption target device group 37 . The guaranteed temperature range is the temperature range in which the operation and durability of the equipment are guaranteed.

The control device 60 shown in FIG. 2 is composed of a well-known microcomputer including CPU, ROM, RAM, etc. and its peripheral circuits. The control device 60 performs various calculations and processes based on control programs stored in the ROM. Various devices to be controlled are connected to the output side of the control device 60 . The control device 60 is a control unit that controls the operation of various controlled devices.

Equipment to be controlled by the controller 60 includes the compressor 11, the first expansion valve 13, the second expansion valve 16, the electric heater 25, the first on-off valve 26a, the second on-off valve 26b, the outdoor fan 40, and the four-way valve. 33, an indoor fan 53, an air mix door servomotor 56, and the like.

The software and hardware for controlling the electric motor of the compressor 11 in the control device 60 is a refrigerant discharge capacity control section. Software and hardware for controlling the first expansion valve 13 and the second expansion valve 16 in the control device 60 are a throttle control section.

The software and hardware for controlling the first on-off valve 26a, the second on-off valve 26b, and the four-way valve 33 in the control device 60 are a valve control unit. The control device 60, the first on-off valve 26a, the second on-off valve 26b, and the four-way valve 33 are flow path switching units that switch the flow path of the cooling water.

The software and hardware for controlling the outdoor fan 40 in the control device 60 is an outdoor air blowing capacity control section. Software and hardware for controlling the indoor fan 53 in the control device 60 is an air blowing capacity control section. The software and hardware for controlling the air mix door servomotor 56 in the controller 60 is an air volume ratio controller.

Various control sensors are connected to the input side of the control device 60 . The various control sensor groups include an inside air temperature sensor 61, an outside air temperature sensor 62, a solar radiation sensor 63, a high temperature cooling water temperature sensor 64, a radiator temperature sensor 65, a device temperature sensor group 66, and the like.

The inside air temperature sensor 61 detects the vehicle interior temperature Tr. An outside air temperature sensor 62 detects outside air temperature Tam. The solar radiation sensor 63 detects the solar radiation Ts inside the vehicle compartment.

The high-temperature cooling water temperature sensor 64 detects the cooling water temperature TWH of the high-temperature cooling water circuit 20 . For example, the high temperature cooling water temperature sensor 64 detects the temperature of the cooling water flowing out from the electric heater 25 . A radiator temperature sensor 65 detects a temperature TWR of cooling water flowing into the radiator 45 .

The device temperature sensor group 66 is a sensor group for detecting the temperature of the first heat absorption target device group 36 and the second heat absorption target device group 37, and includes a battery temperature sensor, a charger temperature sensor, a transaxle temperature sensor, and a motor generator temperature sensor. and an inverter temperature sensor.

The battery temperature sensor detects the temperature of the battery 36a. A charger temperature sensor detects the temperature of the charger 36b. A transaxle temperature sensor detects the temperature of the transaxle 37a. The motor generator temperature sensor detects the temperature of the motor generator 37b. The inverter temperature sensor detects the temperature of the inverter 37c.

Various operation switches (not shown) are connected to the input side of the control device 60 . Various operation switches are provided on the operation panel 70 and are operated by the passenger. The operation panel 70 is arranged near the instrument panel in the front part of the passenger compartment. Operation signals from various operation switches are input to the control device 60 .

Various operation switches are auto switches, air conditioner switches, temperature setting switches, etc. The auto switch is a switch for setting and canceling the 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 indoor air conditioning unit 50 . A temperature setting switch is a switch for setting a preset temperature in the vehicle compartment.

Next, the operation of the above configuration will be explained. Below, the operation of the control device 60 when the auto switch of the operation panel 70 is turned on by the passenger will be described. When the air conditioner switch on the operation panel 70 is turned on by the passenger, the operation mode is switched based on the target air temperature TAO and the like. Operation modes include at least a cooling mode and a dehumidifying and heating mode.

The target blowout temperature TAO is the target temperature of the blowout air blown into the vehicle interior. The control device 60 calculates the target outlet temperature TAO based on the following formula.

TAO = Kset x Tset - Kr x Tr - Kam x Tam - Ks x Ts + C
In this formula, Tset is the vehicle interior set temperature set by the temperature setting switch on the operation panel 70, Tr is the inside temperature detected by the inside temperature sensor 61, Tam is the outside temperature detected by the outside temperature sensor 62, and Ts is It 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.

The control device 60 switches to the cooling mode in the low temperature range of the target blowing temperature TAO, and switches to the dehumidifying heating mode in the high temperature range of the target blowing temperature TAO.

In the dehumidifying and heating mode, the air-side evaporator 14 cools and dehumidifies the air blown into the vehicle compartment, and the heater core 22 heats the air cooled and dehumidified by the air-side evaporator 14 to dehumidify and heat the vehicle compartment.

The control device 60 switches to the heating mode when the air conditioner switch on the operation panel 70 is turned off by the passenger and the target blowout temperature TAO is in the high temperature range.

In the heating mode, the vehicle interior is heated by heating the air blown into the vehicle interior with the heater core 22 without cooling and dehumidifying it with the air-side evaporator 14 .

Next, we will explain the operation in the cooling mode, dehumidifying heating mode, and heating mode. In the cooling mode, the dehumidifying heating mode, and the heating mode, the control device 60 determines the operating states of various control devices connected to the control device 60 (in other words, , control signals to be output to various control devices).

(1) Cooling Mode In the cooling mode, controller 60 operates compressor 11 and high temperature side pump 21 . In the cooling mode, the control device 60 opens the first expansion valve 13 at the throttle opening. In the cooling mode, the controller 60 opens the first on-off valve 26a and the second on-off valve 26b. In the cooling mode, the control device 60 controls the four-way valve 33 so that the cooling water passage to the radiator 45 side is closed.

As a result, the refrigerant flows in the refrigeration cycle device 10 in the cooling mode as indicated by the thick solid line in FIG. That is, the high pressure refrigerant discharged from the compressor 11 flows into the condenser 12 . The refrigerant that has flowed into the condenser 12 releases heat to the cooling water in the high-temperature cooling water circuit 20 . As a result, the refrigerant is cooled and condensed in the condenser 12 .

The refrigerant that has flowed out of the condenser 12 flows into the first expansion valve 13 and is decompressed and expanded by the first expansion valve 13 until it becomes a low-pressure refrigerant. The low-pressure refrigerant decompressed by the first expansion valve 13 flows into the air-side evaporator 14, absorbs heat from the air blown into the vehicle interior, and evaporates. This cools the air blown into the vehicle interior.

Then, the refrigerant that has flowed out of the air-side evaporator 14 flows to the suction side of the compressor 11 and is compressed again by the compressor 11 .

Thus, in the cooling mode, the air-side evaporator 14 allows the low-pressure refrigerant to absorb heat from the air, and the cooled air can be blown out into the passenger compartment. Thereby, cooling of the passenger compartment can be achieved.

In the high-temperature cooling water circuit 20 in the cooling mode, the cooling water of the high-temperature cooling water circuit 20 circulates through the radiator 45, and the radiator 45 radiates heat from the cooling water to the outside air, as indicated by the thick solid line in FIG.

At this time, the cooling water of the high-temperature cooling water circuit 20 also circulates through the heater core 22 , and the amount of heat released from the cooling water to the air in the heater core 22 is adjusted by the air mix door 54 .

The control signal output to the servomotor of the air mix door 54 is determined so that the temperature of the air-conditioned air adjusted by the air mix door 54 reaches the target blowout temperature TAO. Specifically, the degree of opening of the air mix door 54 is determined based on the target outlet 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.

(2) Dehumidifying Heating Mode In the dehumidifying heating mode, the controller 60 operates the compressor 11 , the high temperature side pump 21 and the low temperature side pump 31 . In the dehumidification/heating mode, the control device 60 opens the first expansion valve 13 and the second expansion valve 16 at the throttle opening. In the dehumidification heating mode, the controller 60 opens the first on-off valve 26a and closes the second on-off valve 26b. In the dehumidifying heating mode, the control device 60 controls the four-way valve 33 so that the cooling water flow path to the radiator 45 side is opened.

In the refrigeration cycle device 10 in dehumidification and heating mode, the refrigerant flows as indicated by the thick solid line in FIG. That is, in the refrigerating cycle device 10, the high-pressure refrigerant discharged from the compressor 11 flows into the condenser 12, exchanges heat with the cooling water in the high-temperature cooling water circuit 20, and radiates heat. Thereby, the cooling water in the high-temperature cooling water circuit 20 is heated.

The refrigerant that has flowed out of the condenser 12 flows into the first expansion valve 13 and is decompressed and expanded by the first expansion valve 13 until it becomes a low-pressure refrigerant. The low-pressure refrigerant decompressed by the first expansion valve 13 flows into the air-side evaporator 14, absorbs heat from the air blown into the vehicle interior, and evaporates. This cools and dehumidifies the air blown into the passenger compartment.

At the same time, in the refrigeration cycle device 10, the refrigerant that has flowed out of the condenser 12 flows into the second expansion valve 16 and is decompressed and expanded by the second expansion valve 16 until it becomes a low-pressure refrigerant. The low-pressure refrigerant decompressed by the second expansion valve 16 flows into the cooling water side evaporator 17, absorbs heat from the cooling water in the low-temperature cooling water circuit 30, and evaporates. Thereby, the cooling water in the low-temperature cooling water circuit 30 is cooled.

Then, the refrigerant that has flowed out of the coolant-side evaporator 17 flows to the suction side of the compressor 11 and is compressed again by the compressor 11 .

In the high temperature cooling water circuit 20 in the dehumidification heating mode, the cooling water circulates between the condenser 12 and the heater core 22 as indicated by the thick solid line in FIG. Cooling water does not circulate.

Regarding the control signal output to the servomotor of the air mix door 54, the air mix door 54 is positioned at the solid line position in FIG. The total flow is determined to pass through heater core 22 .

As a result, the heater core 22 radiates heat from the cooling water in the high-temperature cooling water circuit 20 to the air blown into the vehicle interior. Therefore, the air that has been cooled and dehumidified by the air-side evaporator 14 is heated by the heater core 22 and blown into the passenger compartment.

At this time, since the second on-off valve 26b closes the radiator flow path 20c, the cooling water of the high-temperature cooling water circuit 20 does not circulate through the radiator 45. Therefore, the radiator 45 does not radiate heat from the cooling water to the outside air.

In the low-temperature cooling water circuit 30 in the dehumidifying and heating mode, the cooling water of the low-temperature cooling water circuit 30 circulates through the radiator 45 as indicated by the thick solid line in FIG. heat is absorbed from

Thus, in the dehumidifying heating mode, the heat of the high-pressure refrigerant discharged from the compressor 11 is radiated to the cooling water of the high-temperature cooling water circuit 20 by the condenser 12, and the heat of the cooling water of the high-temperature cooling water circuit 20 is dissipated. can be radiated into the air by the heater core 22, and the air heated by the heater core 22 can be blown out into the passenger compartment.

The heater core 22 heats the air that has been cooled and dehumidified by the air-side evaporator 14 . As a result, dehumidification and heating of the passenger compartment can be achieved.

(3) Heating Mode In the heating mode, controller 60 operates compressor 11 , high temperature side pump 21 and low temperature side pump 31 . In the heating mode, the control device 60 closes the first expansion valve 13 and opens the second expansion valve 16 at the throttle opening. In the heating mode, the controller 60 opens the first on-off valve 26a and closes the second on-off valve 26b. In the heating mode, the control device 60 controls the four-way valve 33 so that the coolant flow path to the radiator 45 side is opened.

In the refrigeration cycle device 10 in heating mode, refrigerant flows as indicated by the thick solid line in FIG. That is, in the refrigeration cycle device 10, the refrigerant that has flowed out of the condenser 12 flows into the second expansion valve 16 and is decompressed and expanded by the second expansion valve 16 until it becomes a low-pressure refrigerant. The low-pressure refrigerant decompressed by the second expansion valve 16 flows into the cooling water side evaporator 17, absorbs heat from the cooling water in the low-temperature cooling water circuit 30, and evaporates. Thereby, the cooling water in the low-temperature cooling water circuit 30 is cooled.

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

In the high-temperature cooling water circuit 20 in the heating mode, cooling water circulates between the condenser 12 and the heater core 22 as indicated by the thick solid line in FIG. Water does not circulate.

As a result, the heater core 22 radiates heat from the cooling water in the high-temperature cooling water circuit 20 to the air blown into the vehicle interior. Therefore, the air that has passed through the air-side evaporator 14 (that is, the air that has not been cooled and dehumidified by the air-side evaporator 14) is heated by the heater core 22 and blown into the vehicle compartment.

At this time, since the first on-off valve 26a and the second on-off valve 26b close the radiator flow path 20c, the cooling water of the high-temperature cooling water circuit 20 does not circulate through the radiator 45. Therefore, the radiator 45 does not radiate heat from the cooling water to the outside air.

In the low-temperature cooling water circuit 30 in the heating mode, as shown by the thick solid line in FIG. endothermic.

Thus, in the heating mode, the heat of the high-pressure refrigerant discharged from the compressor 11 is radiated to the cooling water of the high-temperature cooling water circuit 20 by the condenser 12, and the heat of the cooling water of the high-temperature cooling water circuit 20 is released. Heat is radiated to the air by the heater core 22, and the air heated by the heater core 22 can be blown out into the passenger compartment.

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.

In the operation mode described above, when at least one of the first heat absorption target device group 36 and the second heat absorption target device group 37 needs to be cooled, the low temperature side pump 31 is operated to throttle and open the second expansion valve 16. The four-way valve 33 is controlled so that it is opened at a constant temperature and the cooling water is circulated to the equipment that requires cooling among the first heat absorption target equipment group 36 and the second endothermic equipment group 37 .

As a result, the cooling water cooled by the cooling water side evaporator 17 cools the equipment that requires cooling.

In the dehumidification/heating mode or the heating mode, the control device 60 executes the control process shown in the flowchart of FIG. This control process is executed as a subroutine of the control program executed by the control device 60 .

　In step S100, it is determined whether or not the amount of heat required for heating is insufficient. If it is determined in step S100 that the amount of heat necessary for heating (hereinafter referred to as the required amount of heat for heating) is not insufficient, the process returns to the main routine without taking any action.

If it is determined in step S100 that the amount of heat required for heating is insufficient, the process proceeds to step S110, in which it is determined whether or not the shortage of the necessary amount of heat for heating can be resolved by absorbing heat from the first endothermic device group 36. be judged. That is, it is determined whether or not the amount of heat that can be absorbed from the first heat absorption target device group 36 exceeds the required heating heat amount.

For example, the necessary amount of heat for heating is calculated based on the amount of air blown by the indoor blower 53, the intake air temperature of the air-side evaporator 14, and the target outlet temperature TAO. For example, the intake air temperature of the air-side evaporator 14 is calculated based on the introduction ratio of the inside air and the outside air in the inside/outside air switching box 52, the vehicle interior temperature Tr, and the outside air temperature Tam.

The amount of heat that can be absorbed from the first heat absorption target device group 36 is calculated based on the amount of heat generated in each device of the first heat absorption target device group 36, the current temperature, and the lower limit value of the guaranteed temperature range. That is, the amount of heat that can be absorbed while maintaining the temperature of the equipment within the guaranteed temperature range is calculated as the amount of heat that can be absorbed from the first heat absorption target equipment group 36 .

If it is determined in step S110 that the shortage of the required amount of heating heat can be resolved by absorbing heat from the first heat absorption target device group 36, the process proceeds to step S120, where the operation mode is switched to absorb heat from the first heat absorption target device group 36. be done.

If it is determined in step S110 that the shortage of the required amount of heating heat is not resolved by absorbing heat from the first heat absorption target device group 36, the process proceeds to step S130, where the first heat absorption target device group 36 and the second heat absorption target device group It is determined whether or not the shortage of the required amount of heat for heating can be resolved by absorbing heat from 37 . That is, it is determined whether or not the amount of heat that can be absorbed from the first heat absorption target device group 36 and the second heat absorption target device group 37 exceeds the required heating heat amount. The amount of heat that can be absorbed from the second group of devices for heat absorption 37 is calculated in the same manner as the amount of heat that can be absorbed from the first group of devices for heat absorption.

If it is determined in step S130 that the shortage of the necessary amount of heating heat can be resolved by absorbing heat from the first heat absorption target device group 36 and the second heat absorption target device group 37, the process proceeds to step S140, and the first heat absorption target device group. 36 and the second endothermic device group 37 are switched to an operation mode in which heat is absorbed.

In this way, the heat-absorbing device is switched based on the amount of heat generated, so as shown in FIG. 6, the frequency of switching can be reduced compared to the case where the heat-absorbing device is switched based only on the temperature. As a result, it is possible to reduce deterioration in the durability of the four-way valve 33, heat shock to each device, and adverse effects on air conditioning due to frequent switching.

As shown in FIG. 7, the temperature of the cooling water rises by absorbing heat from the heat absorption target equipment, so the amount of heat that can be used for heating increases. Moreover, since the temperature of the device is lowered by absorbing heat from the heat-absorbing target device, the operating efficiency of the device is deteriorated and the amount of heat generated by the device is increased. Therefore, the amount of heat that can be used for heating is further increased.

In the present embodiment, the control device 60 determines in which of the first heat absorption target device group 36 and the second heat absorption target device group 37 the heat absorption target device group is to be absorbed by the cooling water. 2 The four-way valve 33 is controlled by determining based on the temperature and calorific value of the endothermic device group 37 .

In this embodiment, the control device 60 controls the temperature of the heat-absorbing target device group to be equal to or higher than the lower limit value of the guaranteed temperature range, and the heat-absorbing target equipment to be absorbed by the cooling water so that the amount of heat necessary for heating the vehicle interior space can be obtained. Determine the equipment group. Thereby, endothermic switching can be performed appropriately.

In the present embodiment, the control device 60 controls the cooling water from any of the heat absorption target device groups based on the guaranteed temperature range and the ease of heat generation in each of the first heat absorption target device group 36 and the second heat absorption target device group 37. Decide the order of priority for heat absorption. As a result, it is possible to appropriately determine the heat absorption target device group for causing the cooling water to absorb heat.

In this embodiment, the control device 60 estimates the amount of heat generated by the battery 36a based on the value of the output current of the battery 36a. Thereby, heat absorption can be appropriately switched based on the amount of heat generated by the battery 36a.

In this embodiment, the control device 60 estimates the amount of heat generated by the second heat absorption target device group 37, which is the running auxiliary machine, based on the running state of the vehicle. Accordingly, it is possible to appropriately perform heat absorption switching based on the amount of heat generated by the second heat absorption target device group 37 .

The present disclosure is not limited to the above-described embodiments, and can be variously modified as follows without departing from the scope of the present disclosure.

Although cooling water is used as the heat medium in the above embodiment, various media such as oil may be used as the heat medium. A nanofluid may be used as a heat carrier. A nanofluid is a fluid mixed with nanoparticles having a particle size on the order of nanometers.

In the refrigeration cycle apparatus 10 of the above-described embodiment, a freon-based refrigerant is used as a refrigerant, but the type of refrigerant is not limited to this, and natural refrigerants such as carbon dioxide, hydrocarbon-based refrigerants, etc. may be used. good.

Further, the refrigerating cycle device 10 of the above embodiment constitutes a subcritical refrigerating cycle in which the high pressure side refrigerant pressure does not exceed the critical pressure of the refrigerant, but a supercritical refrigerating cycle in which the high pressure side refrigerant pressure exceeds the critical pressure of the refrigerant. may constitute

In the above embodiment, the first heat absorption target device group 36 and the second heat absorption target device group 37 are provided as heat absorption sources, but three or more heat absorption target device groups may be provided. The three or more heat absorption target device groups are arranged in parallel with each other in the flow of the cooling water of the low-temperature cooling water circuit 30, and the cooling water flows and does not flow to each of the three or more heat absorption target device groups. It is sufficient if the state can be switched.

For three or more heat absorption target device groups, the heat absorption target device group that causes the cooling water to absorb heat may be determined based on a predetermined priority.

A heat absorption target device group for heat absorption by the cooling water may be determined by individually combining three or more heat absorption target device groups.

Although the present disclosure has been described with reference to examples, it is understood that the present disclosure is not limited to those examples or structures. The present disclosure also includes various modifications and modifications within the equivalent range. In addition, various combinations and configurations, as well as other combinations and configurations, including single elements, more, or less, are within the scope and spirit of this disclosure.

Claims

a heat medium circuit (30) in which the heat medium circulates;
a plurality of heat absorption sources (36, 37) arranged in the heat medium circuit and absorbed by the heat medium;
a switching unit (33) for switching whether or not the heat medium absorbs heat from a plurality of heat absorption sources;
a compressor (11) that sucks, compresses, and discharges refrigerant;
a heat radiating section (12) for dissipating the refrigerant discharged from the compressor to the air blown into the air-conditioned space;
a decompression unit (16) for decompressing the refrigerant radiated by the heat radiation unit;
an evaporator (17) that evaporates the refrigerant decompressed by the decompression unit by absorbing heat from the heat medium;
a control unit (60) for determining which one of the plurality of heat absorption sources is used to absorb heat by the heat medium based on the temperature and amount of heat generation of the plurality of heat absorption sources, and for controlling the switching unit; Vehicle air conditioner.
The control unit causes the heat medium to absorb heat so that the temperature of the heat absorption source that causes the heat medium to absorb heat is equal to or higher than a lower limit value of a guaranteed temperature range, and the amount of heat necessary for heating the air-conditioned space is obtained. 2. The vehicle air conditioner according to claim 1, wherein the heat absorption source is determined.
The control unit determines an order of priority when causing the heat medium to absorb heat from some of the plurality of heat absorption sources based on a guaranteed temperature range and ease of heat generation in each of the plurality of heat absorption sources. The vehicle air conditioner according to claim 1 or 2.
The vehicle air conditioner according to any one of claims 1 to 3, wherein the plurality of heat absorption sources include a battery (36a) for supplying power for running.
The vehicle air conditioner according to claim 4, wherein the control unit estimates the amount of heat generated by the battery based on the value of the output current of the battery.
The vehicle air conditioner according to any one of claims 1 to 5, wherein the plurality of heat absorption sources include running auxiliary machines (37).
The vehicle air conditioner according to claim 6, wherein the control unit estimates the amount of heat generated by the running auxiliary machine based on the running state of the vehicle.