WO2019138732A1

WO2019138732A1 - Cooling system for vehicle

Info

Publication number: WO2019138732A1
Application number: PCT/JP2018/044454
Authority: WO
Inventors: 圭岡田
Original assignee: 株式会社デンソー
Priority date: 2018-01-10
Filing date: 2018-12-04
Publication date: 2019-07-18

Abstract

This cooling system (1) for a vehicle is provided with: a common flow passage (10), through which a refrigerant flows; an air conditioning flow passage (20) which has an air conditioning opening/closing valve (21) and an air conditioning heat exchanger (23); and a cooling flow passage (30) which has a cooling opening/closing valve and a cooling heat exchanger (33). The cooling system for a vehicle is provided with a control unit (50) which controls the air conditioning opening/closing valve to be in a closed state and controls the cooling opening/closing valve to be in an open state when there is a request for cooling, by which cooling is to be performed by using the cooling heat exchanger and an ambient temperature, which is a temperature at an upstream side of an air flow with respect to the air conditioning heat exchanger, is lower than a lower limit temperature. That is, the refrigerant does not flow to the air conditioning flow passage but flows to the cooling flow passage, when heat enough to vaporize the refrigerant cannot be obtained in the air conditioning heat exchanger. Accordingly, the refrigeration operation by using the cooling flow passage can be stably maintained by reducing an operation failure, such as a liquid back to the compressor (11) or the like.

Description

Vehicle cooling system

Cross-reference to related applications

This application is related to Japanese Patent Application No. 2018-002125 filed on Jan. 10, 2018 and Japanese Patent Application No. 2018 filed on Oct. 24, 2018, the disclosure contents of which are incorporated by reference into the present application. -Based on the No. -200323.

The disclosure in this specification relates to a vehicle cooling system.

Patent Document 1 discloses a cooling system that includes an indoor air conditioning unit and a secondary battery, and performs an air conditioning operation and a cooling operation of the secondary battery using a common refrigerant. The cooling system is configured to perform the function of adjusting the temperature of the indoor blowing air blown into the vehicle compartment and to perform the function of adjusting the temperature of the battery blowing air blown toward the secondary battery. There is.

JP, 2014-160594, A

In the prior art configuration, when performing battery cooling, battery cooling alone operation is performed when there is no air conditioning request, but when there is air conditioning request, control is performed so that air conditioning operation is performed simultaneously with battery cooling operation. The In this case, the air conditioning operation is continued even under conditions where the refrigeration cycle can not exhibit sufficient refrigeration capacity, such as a very low outside temperature, which causes a liquid-bag phenomenon or frost formation on the heat exchanger. The Alternatively, when it is determined that the refrigeration cycle can not be operated, the operation of the entire refrigeration cycle is stopped by stopping the compressor or the like. For this reason, when the refrigeration cycle can not be operated with the original refrigeration capacity due to the air conditioning operation, sufficient cooling can not be performed also for the cooling operation of the object to be cooled such as the secondary battery. In the above aspects, or in other aspects not mentioned, there is a need for further improvements in vehicle cooling systems.

One object disclosed is to provide a vehicle cooling system that can stably cool an object to be cooled.

The vehicle cooling system disclosed herein includes a common flow path through which a refrigerant flows by connecting a compressor and an outdoor heat exchanger, an air conditioning heat exchanger used when air conditioning the interior of the vehicle, and a common flow path Are connected to the air conditioning flow path for providing a flow path through which the refrigerant flows to the air conditioning heat exchanger, and provided in the air conditioning flow path for controlling the amount of refrigerant flowing into the air conditioning heat exchanger An open / close valve, a cooling heat exchanger used to cool a cooling object mounted on a vehicle, and a cooling channel connected to a common flow channel and providing a flow channel through which the refrigerant flows to the cooling heat exchanger And an on-off valve for cooling which is provided in the cooling flow path to control the amount of refrigerant flowing into the heat exchanger for cooling, an air conditioning fan for blowing air to the air conditioning heat exchanger, and a wind by the air conditioning fan. Temperature sensor provided upstream of the air conditioning heat exchanger, and the object to be cooled If there is a demand for cooling and the ambient temperature measured by the temperature sensor is lower than the lower limit temperature set to a temperature higher than the evaporation temperature of the refrigerant in the air conditioning heat exchanger, close the air conditioning on-off valve And a controller for opening the cooling on-off valve.

According to the disclosed vehicle cooling system, the control unit is in the case where there is a cooling request to cool the object to be cooled, and the ambient temperature of the air conditioning heat exchanger is lower than the lower limit temperature. Is closed and the cooling on-off valve is open. For this reason, when the heat exchanger for air conditioning can not obtain sufficient heat to evaporate the refrigerant from the surroundings, the refrigerant is not flowed in the air conditioning channel, and the cooling using the cooling channel is maintained. There is. Therefore, it is possible to reduce the occurrence of operation failure due to the liquid back phenomenon in which the liquid refrigerant is sucked into the compressor, the formation of frost on the surface of the air conditioning heat exchanger, and the like. Furthermore, since it is possible to avoid the occurrence of operation failure caused by the air conditioning heat exchanger without stopping the compressor, the cooling operation of the object to be cooled using the cooling flow path can be stably maintained.

It is a block diagram which shows the structure of the cooling system for vehicles. It is a block diagram regarding control of a cooling system for vehicles. It is a block diagram which shows the structure of the cooling system for vehicles in combined use driving | operation. It is a block diagram which shows the structure of the cooling system for vehicles in heating operation. It is a flow chart about control of a cooling system for vehicles. It is a block diagram which shows the structure of the cooling system for vehicles in 2nd Embodiment. It is a block diagram which shows the structure of the cooling system for vehicles in 3rd Embodiment. It is a block diagram which shows the structure of the cooling system for vehicles in 4th Embodiment. It is a flowchart regarding control of the cooling system for vehicles in a 5th embodiment.

Hereinafter, a plurality of modes for carrying out the present disclosure will be described with reference to the drawings. The same referential mark may be attached | subjected to the part corresponding to the matter demonstrated by the form preceded in each form, and the overlapping description may be abbreviate | omitted. When only a part of the configuration is described in each form, the other forms described above can be applied to other parts of the configuration. Not only combinations of parts which clearly indicate that combinations are possible in each embodiment, but also combinations of embodiments even if they are not specified unless there is a problem with the combination. Is also possible.

Several embodiments will be described with reference to the drawings. In embodiments, functionally and / or structurally corresponding portions and / or associated portions may be provided with the same reference symbols, or reference symbols with different places of one hundred or more places. The description of the other embodiments can be referred to for the corresponding parts and / or parts to be associated.

First Embodiment In FIG. 1, a vehicle cooling system 1 is mounted on a vehicle. The vehicle cooling system 1 includes an air conditioning function that performs an air conditioning operation in a vehicle compartment. The air conditioning operation includes an operation of adjusting the temperature of the air in the passenger compartment, such as a cooling operation and a heating operation. The air conditioning operation includes an operation of adjusting the humidity of the air in the passenger compartment, such as a dehumidifying operation. In the air conditioning operation, necessary air conditioning is performed by flowing the conditioned air into the vehicle compartment using the air conditioning duct 2.

The vehicle cooling system 1 has a cooling function for performing a cooling operation for cooling an object to be cooled mounted in a vehicle compartment. The cooling operation includes an operation of cooling electronic parts such as the secondary battery 35 which is a heat-generating part. The cooling operation includes an operation of cooling the heat medium used to cool the object to be cooled. In other words, the cooling operation includes an operation of directly cooling the object to be cooled and an operation of indirectly cooling the object to be cooled via a heat medium such as air. In the cooling operation, necessary cooling is performed by flowing cooling air to the object to be cooled using the battery duct 3 having the secondary battery 35 as the object to be cooled therein.

The object to be cooled is not limited to the secondary battery 35 as long as it is an object requiring cooling. For example, it may be a charger or a power control unit used together with the secondary battery 35. For example, it may be an electronic device used for control such as automatic operation. For example, it may be a transaxle provided with a motor, a generator, and the like.

The vehicle cooling system 1 includes a common flow passage 10 through which a refrigerant flows, an air conditioning flow passage 20, and a battery flow passage 30. The air conditioning flow passage 20 is a refrigerant flow passage used when performing an air conditioning operation such as a cooling operation of a vehicle compartment. The battery flow path 30 is a refrigerant flow path used when performing a cooling operation for cooling the secondary battery 35 which is a cooling object. The common flow path 10 is a refrigerant flow path commonly used in both the air conditioning operation and the cooling operation. In other words, the common flow passage 10, the air conditioning flow passage 20, and the battery flow passage 30 constitute the refrigerant circuit of the refrigeration cycle in the vehicle cooling system 1.

The common flow passage 10 includes a compressor 11, a condenser 12 and an outdoor heat exchanger 13. The compressor 11 is a device that sucks in and compresses a gaseous refrigerant and discharges the refrigerant in a high temperature and high pressure state. The compressor 11 is a motor-driven compressor driven using electric power. Therefore, the on / off control of the compressor 11 and the operating frequency of the compressor 11 can be arbitrarily controlled. However, power may be obtained in conjunction with driving of the engine instead of the electric compressor. The condenser 12 is a device that causes the heat of the high-temperature and high-pressure refrigerant to be dissipated to the surroundings to condense the gaseous refrigerant into a liquid. The outdoor heat exchanger 13 is a device that exchanges heat between the outside air and the refrigerant. In order to promote heat exchange in the outdoor heat exchanger 13, a blower may be provided to send wind to the outdoor heat exchanger 13.

The air conditioning flow passage 20 is a flow passage connecting the downstream side of the outdoor heat exchanger 13 in the common flow passage 10 and the suction side of the compressor 11. The air conditioning channel 20 includes an air conditioning switching valve 21, an air conditioning expansion valve 22, and an air conditioning heat exchanger 23. The air conditioning on-off valve 21 is a valve device that switches between a state in which the refrigerant flows and a state in which the refrigerant does not flow in the air conditioning channel 20. The air conditioning expansion valve 22 is a valve device that expands the refrigerant flowing in the air conditioning channel 20. In other words, the air conditioning expansion valve 22 is a pressure reducing device that causes the refrigerant to have a pressure difference before and after passing through the air conditioning expansion valve 22 to facilitate evaporation of the refrigerant. The air conditioning heat exchanger 23 is a device that exchanges heat between the air blown into the vehicle compartment and the refrigerant. The air conditioning heat exchanger 23 removes the heat of vaporization from the surrounding air by evaporating the refrigerant inside. The air conditioning heat exchanger 23 is used as a cooling source in the cooling operation.

At the uppermost stream of the flow of the conditioned air, which is the inlet of the air conditioning duct 2, an inside / outside air switching door 25 is provided. The inside / outside air switching door 25 is a device that switches between taking in the inside air or taking in the outside air in the air conditioning operation of the vehicle. When the air conditioning operation is in the inside air circulation mode, the inside / outside air switching door 25 is switched so as to open the inside air side, and the air conditioning air is circulated in the vehicle interior. On the other hand, when the air conditioning operation is in the outside air introduction mode, the inside / outside air switching door 25 is switched so that the outside air side is opened, and air is taken in from the outside of the vehicle to flow in the vehicle interior.

An air conditioning blower 26 is provided between the inside / outside air switching door 25 and the air conditioning heat exchanger 23. The air conditioning blower 26 is a device for sending the conditioned air into the vehicle compartment. The air conditioning blower 26 blows air toward the air conditioning heat exchanger 23 and the heating heat exchanger 43. An air conditioning temperature sensor 27 is provided between the air conditioning blower 26 and the air conditioning heat exchanger 23. The air conditioning temperature sensor 27 is a sensor that measures the ambient temperature of the air conditioning heat exchanger 23. The temperature sensor 27 for air conditioning is located upstream of the heat exchanger 23 for air conditioning in the flow of the wind by the air blower 26 for air conditioning. The ambient temperature is the temperature of the air before heat exchange with the air conditioning heat exchanger 23 measured by the air conditioning temperature sensor 27.

The battery flow passage 30 is a flow passage connecting the downstream side of the outdoor heat exchanger 13 in the common flow passage 10 and the suction side of the compressor 11 as in the air conditioning flow passage 20. The battery channel 30 includes a battery on-off valve 31, a battery expansion valve 32, and a battery heat exchanger 33. The on-off valve 31 for battery is a valve device that switches between a state in which the refrigerant flows and a state in which the refrigerant does not flow in the battery channel 30. The battery expansion valve 32 is a valve device that expands the refrigerant flowing in the battery flow path 30. In other words, the battery expansion valve 32 is a pressure reducing device that makes the refrigerant have a pressure difference before and after passing through the battery expansion valve 32 to facilitate evaporation of the refrigerant. The battery heat exchanger 33 is a device that performs heat exchange between the air and the refrigerant blown to the secondary battery 35 which is a heat-generating component. The battery heat exchanger 33 removes the heat of vaporization from the surrounding air by evaporating the refrigerant inside. The battery heat exchanger 33 is used as a cooling source in the cooling operation. The battery channel 30 provides a cooling channel. The battery on-off valve 31 provides a cooling on-off valve. The battery heat exchanger 33 provides a cooling heat exchanger.

The battery duct 3 has a shape in which air circulates inside. The battery duct 3 does not have an opening or the like for introducing outside air into the duct. For this reason, in the battery duct 3, an air path is provided which circulates the inside air to cool the object to be cooled without actively introducing the outside air. However, the battery duct 3 may be provided with an opening through which outside air can be introduced.

Inside the battery duct 3, a battery heat exchanger 33, a secondary battery 35 and a battery blower 36 are provided. The secondary battery 35 functions as a battery that supplies power to the vehicle. The secondary battery 35 is a heat-generating component that is particularly susceptible to large heat generation at the time of power supply for supplying power to the vehicle and at the time of charge storage for storing power by recovery of regenerative energy and external power supply via a charger. is there. The secondary battery 35 includes a battery temperature sensor 37 that measures the temperature of the secondary battery 35. The battery temperature sensor 37 is provided in direct contact with the secondary battery 35. The battery blower 36 is a device for sending the cooling air heat-exchanged by the battery heat exchanger 33 toward the secondary battery 35. The secondary battery 35 provides an object to be cooled.

The vehicle cooling system 1 includes a heating flow passage 40 through which a heat medium flows. The heating flow path 40 is a flow path used when performing an air conditioning operation such as a heating operation of the vehicle interior. The heating flow path 40 is a flow path independent of the common flow path 10, the air conditioning flow path 20, and the battery flow path 30 that constitute the refrigeration cycle. The heat medium flowing through the heating channel 40 is, for example, a liquid such as water or an antifreeze liquid.

The heating channel 40 includes a pump 41, a condenser 12, a heating heat exchanger 43, a reservoir tank 44, and a heater 45. The pump 41 is a device that causes a heat medium to flow through the heating flow path 40. The reservoir tank 44 is a device that adjusts the pressure so that the pressure in the heating flow passage 40 does not increase excessively even if the volume of the heat medium increases as the temperature rises. The heating heat exchanger 43 is a device that exchanges heat between the heat medium flowing inside and the air flowing around. The heater 45 is a device for heating a heat medium circulating in the heating flow path 40.

The condenser 12 exchanges heat between the refrigerant flowing in the common flow passage 10 and the heat medium flowing in the heating flow passage 40. Here, the refrigerant flowing through the common flow passage 10 is in a high temperature state as it is compressed by the compressor 11. Therefore, the condenser 12 has the function of heating the heat medium as the heater 45 does.

In FIG. 2, the vehicle cooling system 1 includes a control unit 50 that controls the operation of the vehicle cooling system 1. The control unit 50 is connected to the air conditioning temperature sensor 27, the air conditioning switch 29, and the battery temperature sensor 37. The control unit 50 acquires the ambient temperature upstream of the air conditioning heat exchanger 23 from the air conditioning temperature sensor 27. Further, the temperature of the secondary battery 35 is acquired from the battery temperature sensor 37. The control unit 50 acquires information on the air conditioning operation from the air conditioning switch 29. The air conditioning switch 29 is a switch operated by the occupant, and is a device for setting information regarding the air conditioning operation such as ON / OFF of the air conditioning operation, and which mode of the air conditioning target temperature and the inside air circulation mode or the outside air introduction mode is selected. It is.

The control unit 50 is connected to the compressor 11. The control unit 50 controls the on / off of the operation of the compressor 11 and the operation frequency to control the presence or absence of cooling in the air conditioning operation and the battery cooling operation and the magnitude of the cooling capacity.

The control unit 50 is connected to the air conditioning on-off valve 21, the inside / outside air switching door 25, and the air conditioning blower 26. The control unit 50 performs control to switch the air conditioning on / off valve 21 between the open state and the closed state. Furthermore, in the open state of the air conditioning on-off valve 21, it is possible to set the throttle state where the flow rate of the refrigerant that can pass is restricted by controlling the size of the opening degree. That is, it is possible to finely control the increase and decrease of the flow rate of the refrigerant passing through the air conditioning on-off valve 21. The control unit 50 controls the inside / outside air switching door 25 based on the information set by the air conditioning switch 29 to switch between the inside air circulation mode and the outside air introduction mode. However, even in the state where the inside air circulation mode is selected by the occupant, control may be performed to forcibly switch to the outside air introduction mode for the purpose of anti-fogging of the windshield. The control unit 50 controls the air-conditioning fan 26 to adjust the amount of air passing through the air-conditioning heat exchanger 23.

The control unit 50 is connected to the battery on-off valve 31 and the battery blower 36. The control unit 50 performs control to switch the battery on-off valve 31 between the open state and the closed state. Furthermore, in the open state of the battery on-off valve 31, it is possible to set the throttle state where the flow rate of the refrigerant that can pass is restricted by controlling the size of the opening degree. That is, it is possible to finely control the increase and decrease of the flow rate of the refrigerant passing through the on-off valve 31 for the battery. The control unit 50 controls the battery blower 36 to adjust the amount of air blown to the secondary battery 35 through the battery heat exchanger 33.

The control unit 50 is connected to the pump 41 and the heater 45. The control unit 50 controls the on / off of the operation of the pump 41 and the magnitude of the output to control the presence or absence of the heating operation and the magnitude of the heating capacity. The control unit 50 controls the magnitude of the heating capacity by controlling the on / off of the heater 45 and the magnitude of the output. Here, when the heat medium flowing through the heating flow path 40 can be sufficiently heated by heat exchange with the high temperature refrigerant using the condenser 12, the heater 45 may not operate even during the heating operation. .

FIG. 3 shows a state in which the cooling operation of the passenger compartment and the cooling operation of the secondary battery 35 are simultaneously performed. The heating operation has been stopped. The operation of the vehicle cooling system 1 will be described below. In the figure, the flow path through which the refrigerant and the heat medium flow is indicated by a solid line, and the flow path through which the refrigerant and the heat medium do not flow is indicated by a broken line.

By operating the compressor 11, the refrigerant is caused to flow in the refrigerant flow path such as the common flow path 10. In the condenser 12, the refrigerant exchanges heat with the heat medium of the heating flow passage 40, but since the heat medium of the heating flow passage 40 is not circulated, the heat exchange can not be actively performed. In other words, the heat of the refrigerant can not be positively dissipated, and the condensation of the refrigerant is not promoted so much.

The refrigerant having flowed out of the condenser 12 flows into the outdoor heat exchanger 13. In the outdoor heat exchanger 13, heat exchange between the outside air and the refrigerant reduces the temperature of the refrigerant. Here, when there is a gas refrigerant that can not be condensed in the condenser 12, it is cooled by the outdoor heat exchanger 13 and condensed to a liquid refrigerant. The air conditioning on-off valve 21 and the battery on-off valve 31 are both open. For this reason, the refrigerant which has flowed out of the outdoor heat exchanger 13 is divided into two flow paths of the air conditioning flow path 20 and the battery flow path 30 and flows in the respective flow paths.

The refrigerant flowing through the air conditioning flow passage 20 passes through the air conditioning opening / closing valve 21 in the open state and is expanded by the air conditioning expansion valve 22. In other words, the refrigerant is depressurized and easily evaporated. Thereafter, in the process of flowing through the air conditioning heat exchanger 23, the heat of vaporization is taken from the surrounding air to evaporate the refrigerant. In other words, the air conditioning heat exchanger 23 functions as a cooling source that cools the surrounding air. The refrigerant having passed through the air conditioning heat exchanger 23 is sucked into the compressor 11 to repeat a series of circulations.

The refrigerant flowing in the battery flow passage 30 passes through the open / close battery on / off valve 31 and is expanded by the battery expansion valve 32. In other words, the refrigerant is depressurized and easily evaporated. Thereafter, in the process of flowing through the battery heat exchanger 33, the refrigerant heats off by taking away the heat of vaporization from the surrounding air. In other words, the battery heat exchanger 33 functions as a cooling source for cooling the ambient air. The refrigerant having passed through the battery heat exchanger 33 is sucked into the compressor 11 to repeat a series of circulations.

In the air conditioning duct 2, the air sent by the air conditioning blower 26 is cooled by the air conditioning heat exchanger 23. Thereafter, although the air conditioning air passes through the heating heat exchanger 43, since the heat medium is not circulating in the heating heat exchanger 43, the air conditioning air heat is hardly heated, and the air conditioning heat exchanger 23 It is sent to the passenger compartment as a cooled cold air.

Here, if the ambient temperature of the air conditioning heat exchanger 23 is lower than the evaporation temperature of the refrigerant, the air conditioning heat exchanger 23 can not deprive the ambient air of sufficient vaporization heat. As a result, a liquid back phenomenon in which the refrigerant can not evaporate and is sucked as a liquid into the compressor 11 may be caused. Such a liquid back phenomenon is that the air conditioning heat exchanger 23 exchanges heat with low temperature outside air when the cooling operation is performed in the outside air circulation mode while traveling in a cold area where the outside temperature is below freezing or the like. It is easy to be caused by.

In addition, frost formation may occur on the surface of the air conditioning heat exchanger 23 when the air conditioning heat exchanger 23 is exposed to the outside air at 0 ° C. or less. When frost forms on the surface of the air conditioning heat exchanger 23, the refrigerant can not appropriately exchange heat with air, which may cause a reduction in heat exchange efficiency. Furthermore, by performing the heating operation with the frost on the air conditioning heat exchanger 23, the heating operation may require more energy than usual.

Further, in the refrigeration cycle provided with an accumulator for preventing liquid back upstream of the compressor 11, a large amount of liquid refrigerant is stored in the accumulator, and the liquid refrigerant is accumulated also in the air conditioning heat exchanger 23. There is a possibility that In this state, the amount of refrigerant necessary for the entire refrigeration cycle may be insufficient, and an appropriate amount of refrigerant may not be allowed to flow through the battery flow path 30.

In the inside of the battery duct 3, the air sent by the battery blower 36 is cooled by the battery heat exchanger 33. Thereafter, the cooling air exchanges heat with the secondary battery 35 to cool the secondary battery 35. In other words, the cooling air is heated by the secondary battery 35. Therefore, in the battery heat exchanger 33, it is possible to remove the heat of vaporization from the air that has received the heat generated from the secondary battery 35 and evaporate it. Therefore, since the ambient temperature of the battery heat exchanger 33 is too low, it is unlikely that the heat of vaporization can not be taken away. In other words, it is difficult to cause a liquid back phenomenon in which the refrigerant flowing in the battery flow path 30 can not be evaporated and is sucked into the compressor 11 as a liquid as it is. In addition, a malfunction due to frost formation on the battery heat exchanger 33 is less likely to occur as compared to the air conditioning heat exchanger 23.

FIG. 4 shows a state in which a battery cooling standalone operation is performed on the secondary battery 35. That is, while performing the battery cooling operation, the cooling operation is stopped. In addition, the heating operation is being performed simultaneously with the battery cooling operation. The operation of the vehicle cooling system 1 will be described below. In the figure, the flow path through which the refrigerant and the heat medium flow is indicated by a solid line, and the flow path through which the refrigerant and the heat medium do not flow is indicated by a broken line.

By operating the compressor 11, the refrigerant is caused to flow in the refrigerant flow path such as the common flow path 10. In the condenser 12, the refrigerant is in a state of actively exchanging heat with the heat medium flowing through the heating flow path 40. In other words, the high temperature refrigerant is actively heating the heat medium.

The liquid refrigerant that has flowed out of the condenser 12 is cooled in the process of flowing through the outdoor heat exchanger 13. Since the air conditioning on-off valve 21 is in the closed state and the battery on-off valve 31 is in the open state, the refrigerant flowing out of the outdoor heat exchanger 13 flows only through the battery flow path 30, and the air conditioning flow path 20 is Not flowing.

The refrigerant flowing through the battery flow passage 30 passes through the battery on-off valve 31 and is expanded by the battery expansion valve 32. Thereafter, the heat of vaporization is removed from the surrounding air in the battery heat exchanger 33 to evaporate the refrigerant. The refrigerant having passed through the battery heat exchanger 33 is sucked into the compressor 11 to repeat a series of circulations. Here, the refrigerant flows only in the battery flow path 30 in which it is difficult to cause a malfunction such as a liquid back phenomenon or frost formation. Therefore, it is easy to stably maintain the operating state of the refrigeration cycle. In other words, since the refrigerant does not flow in the air conditioning channel 20, it is difficult to cause the malfunction of the refrigeration cycle.

By operating the pump 41, the heat medium is flowed to the heating flow path 40. In the condenser 12, the heat medium flowing through the heating flow path 40 is heated by receiving heat from the high temperature refrigerant. At this time, since the refrigerant has the heat accompanying the compression in the compressor 11 and the heat absorbed from the exhaust heat of the secondary battery 35, the heat medium including the heat generated in the secondary battery 35 is also heated It will be done. Furthermore, in the condenser 12, the flow of the refrigerant and the flow of the heat medium are in a countercurrent relationship. That is, heat exchange can be performed more efficiently than in the case of flowing in parallel flow by the two fluids flowing in opposite directions. The heat medium heated by the condenser 12 is further heated by the heater 45. However, when the condenser 12 is sufficiently heated, the heating by the heater 45 may be omitted. That is, by finely controlling the output in the heater 45, the heat medium just before flowing into the heating heat exchanger 43 can be heated to an appropriate temperature.

The heat medium heated by the condenser 12 and the heater 45 flows into the heating heat exchanger 43. The heating heat exchanger 43 heats the air by exchanging heat between the heat medium flowing inside and the surrounding air. In other words, the heating heat exchanger 43 functions as a heating source for warming the ambient air. The heat medium having passed through the heating heat exchanger 43 flows into the reservoir tank 44 and is then sucked into the pump 41 again to repeat a series of circulations.

Inside the air conditioning duct 2, the air sent by the air conditioning blower 26 is heated by the heating heat exchanger 43. Although the air conditioning air passes through the air conditioning heat exchanger 23 upstream of the air flow from the heating heat exchanger 43, the refrigerant is not circulated in the air conditioning heat exchanger 23. For this reason, the refrigerant and the air are sent to the vehicle interior as warm air heated by the heating heat exchanger 43 with almost no heat exchange.

In the heating operation, since the exhaust heat of the refrigerant can be recovered by heat exchange in the condenser 12, it is preferable that a high temperature refrigerant flows in the condenser 12 by simultaneously performing an independent operation of battery cooling. According to this, the energy consumed by the heater 45 can be reduced. In particular, by flowing the refrigerant through the battery flow path 30, the exhaust heat of the secondary battery 35 can be recovered and used for the heating operation, so the heating operation can be performed more efficiently.

The flow of control in the cooling operation of the vehicular cooling system 1 will be described below. In FIG. 5, when the driver of the vehicle cooling system 1 is started by pressing the cooling operation switch or the like by the occupant, the lower limit temperature is first calculated in step S101. Here, the lower limit temperature is the lower limit value of the temperature range in which the refrigeration cycle can be appropriately operated when the refrigerant is circulated in the air conditioning flow passage 20. In other words, when the ambient temperature of the air conditioning heat exchanger 23 is higher than the lower limit temperature, the refrigerant can deprive the surrounding air of the heat of vaporization in the air conditioning heat exchanger 23 and evaporate it. Never return to That is, the refrigeration cycle can be appropriately operated. On the other hand, if the ambient temperature is lower than the lower limit temperature, the air conditioning heat exchanger 23 can not deprive the vaporization heat sufficiently, and the operation failure due to the liquid back phenomenon or the like in which the liquid refrigerant is sucked into the compressor 11 May be triggered. That is, the refrigeration cycle can not be properly operated.

The lower limit temperature is a temperature equal to or higher than the evaporation temperature of the refrigerant in the air conditioning heat exchanger 23. For example, when the evaporation temperature in the air conditioning heat exchanger 23 is 5 ° C. and the inside / outside air switching door 25 is in the outside air introduction mode, a margin of 5 ° C. is added to the evaporation temperature of 5 ° C. 10 ° C. is calculated as the lower limit temperature. When the evaporation temperature in the air conditioning heat exchanger 23 is 5 ° C. and the inside / outside air switching door 25 is in the internal air circulation mode, 8 ° C. obtained by adding 3 ° C. margin to the evaporation temperature 5 ° C. Is calculated as the lower limit temperature. Here, the reason that the degree of margin differs between the outside air introduction mode and the inside air circulation mode is that the change of the ambient temperature is often more abrupt in the outside air introduction mode than in the inside air circulation mode. However, the value of the lower limit temperature is not limited to the value described above, and a temperature equal to the evaporation temperature may be set as the lower limit temperature. Alternatively, a margin larger than 5 ° C. may be set with respect to the evaporation temperature. Also, the lower limit temperature may be set to an arbitrary temperature by the occupant of the vehicle.

In the calculation of the lower limit temperature, elements other than the evaporation temperature in the air conditioning heat exchanger 23 and the inside / outside air switching door 25 may be included. For example, if the air volume of the air conditioning blower 26 is equal to or more than the threshold value, the lower limit temperature may be set higher than in the case of being less than the threshold value. Further, the lower limit temperature may be changed depending on the type of refrigerant and the capacity of the compressor 11. After setting the lower limit temperature, the process proceeds to step S102.

In step S102, the ambient temperature of the air conditioning heat exchanger 23 is measured using the air conditioning temperature sensor 27. Here, the ambient temperature in the outside air introduction mode is a temperature substantially equal to the outside air temperature. Therefore, the ambient temperature is likely to change depending strongly on the external environment. Specifically, it is assumed that the outside air temperature changes rapidly as it gets out of the state of being stored in the garage. Alternatively, there may be a case where the ambient temperature is high due to the exhaust heat from the surrounding vehicles during the traffic congestion, but the ambient temperature is rapidly lowered due to the passing of the traffic congestion. On the other hand, the ambient temperature in the internal air circulation mode does not depend so strongly on the external environment, and the ambient temperature hardly changes. After measuring the ambient temperature, the process proceeds to step S111.

In step S111, it is determined whether the measured ambient temperature is a temperature equal to or higher than the lower limit temperature. If the ambient temperature is equal to or higher than the lower limit temperature, it is determined that the air around the air conditioning heat exchanger 23 has heat sufficient for evaporation of the refrigerant, and the process proceeds to step S112. On the other hand, if the ambient temperature is less than the lower limit temperature, it is determined that the air around the air conditioning heat exchanger 23 does not have sufficient heat for evaporation of the refrigerant, and the process proceeds to step S113.

In step S112, the air conditioning valve 21 is opened. That is, the refrigerant can be circulated in the air conditioning channel 20. On the other hand, in step S113, the air conditioning on-off valve 21 is closed. That is, the refrigerant can not circulate in the air conditioning flow passage 20. Thus, in a state where there is a high possibility that an operation failure due to a liquid back phenomenon or the like is caused in the refrigeration cycle, the state of the air conditioning on-off valve 21 is switched so as not to flow the refrigerant. After the air conditioning on-off valve 21 is opened or closed, the process proceeds to step S121.

In step S121, it is determined whether there is a battery cooling request indicating whether the secondary battery 35 needs to be cooled. If there is no battery cooling request for the secondary battery 35, it is determined that the secondary battery 35 does not need to be cooled, and the process proceeds to step S122. On the other hand, when there is a battery cooling request for the secondary battery 35, it is determined that the secondary battery 35 needs to be cooled, and the process proceeds to step S123. Here, the presence or absence of the battery cooling request is determined depending on, for example, whether the temperature of the secondary battery 35 measured by the battery temperature sensor 37 is lower than the threshold or higher than the threshold. However, the presence or absence of the battery cooling request may be switched by the occupant. Alternatively, regardless of the temperature of the secondary battery 35, a battery cooling request may always be made. In this case, it is preferable to prevent the secondary battery 35 from being excessively cooled by adjusting the opening degree of the battery expansion valve 32 and the cooling capacity using the battery blower 36.

In step S122, the on-off valve 31 is closed. That is, the refrigerant can not be circulated in the battery channel 30. Not limited to step S122, when both the air conditioning on-off valve 21 and the on-off valve 31 for the battery are simultaneously closed, the compressor before the on-off valve 31 for the battery is completely closed. Stop the operation of 11. This prevents the refrigerant pressure from becoming abnormally high in the refrigerant circulation channel. However, if there is a flow path through which the refrigerant can circulate other than the air conditioning flow path 20 and the battery flow path 30, etc., the operation of the compressor 11 is maintained when the high pressure does not become abnormal due to the operation of the compressor 11. May be After the battery on-off valve 31 is closed, the process proceeds to step S131.

In step S131, it is determined whether the air conditioning switch 29 is on or off. If the air conditioning switch 29 is in the off state, both the air conditioning operation and the battery cooling operation are unnecessary, so the compressor 11 is stopped and the operation of the vehicle cooling system 1 is ended. On the other hand, if the air conditioning switch 29 is in the on state, the process returns to step S101 to repeat the control flow of the series of the vehicle cooling system 1 in order to maintain the air conditioning operation.

In step S123, the on-off valve 31 for battery is opened. That is, the refrigerant can be circulated in the battery flow path 30. Thereafter, the on / off state of the air conditioning switch 29 is determined in step S124. If the air conditioning switch 29 is in the off state, only the battery cooling operation is required, so the process returns to step S113 to close the air conditioning on-off valve 21. On the other hand, if the air conditioning switch 29 is in the on state, the process returns to step S101 to repeat the control flow of the series of the vehicle cooling system 1 in order to maintain the air conditioning operation.

According to the embodiment described above, the control unit 50 has the cooling request for cooling the object to be cooled, and the ambient temperature of the air conditioning heat exchanger 23 is lower than the lower limit temperature. Is closed, and the on-off valve 31 is opened. Therefore, when there is a possibility that the refrigerant can not be sufficiently evaporated in the air conditioning heat exchanger 23, the refrigerant does not flow to the air conditioning heat exchanger 23. Therefore, it is possible to reduce the occurrence of malfunction such as a liquid back phenomenon in which the liquid refrigerant is sucked into the compressor 11. This is particularly useful in cold regions where the outside air temperature is much lower than the freezing point, since the ambient temperature tends to be low.

Furthermore, there is no need to stop the compressor 11 for the purpose of stopping the air conditioning operation. Therefore, even when the air conditioning operation is stopped, the compressor 11 can be operated to perform the battery cooling operation. Therefore, regardless of the presence or absence of the air conditioning operation, the secondary battery 35 can be cooled to maintain the secondary battery 35 within an appropriate temperature range.

When the inside / outside air switching door 25 is in the outside air introduction mode, the lower limit temperature is set higher than in the inside air circulation mode. Therefore, the air conditioning on-off valve 21 is closed at an earlier stage in the outside air introduction mode than in the inside air circulation mode. Therefore, it is possible to prevent the occurrence of malfunction such as the liquid back phenomenon with higher accuracy in the outside air introduction mode in which the change of the ambient temperature is likely to be severe due to the outside air being taken in. In other words, it is more difficult to forcibly close the air conditioning on-off valve 21 in the inside air circulation mode than in the outside air circulation mode. For this reason, it is easy to maintain the air conditioning operation in the inside air circulation mode for a long time to keep the passenger compartment at a comfortable temperature.

The condenser 12 exchanges heat between the heat medium flowing in the heating flow passage 40 and the refrigerant flowing in the common flow passage 10 from the compressor 11 toward the outdoor heat exchanger 13. For this reason, in the condenser 12, the heat medium flowing through the heating flow path 40 is heated by the high temperature refrigerant. Therefore, the exhaust heat of the refrigerant can be recovered and used as heat in the heating operation.

In the condenser 12, the heat medium flowing in the heating flow passage 40 and the refrigerant flowing in the common flow passage 10 flow in the direction opposite to each other. Therefore, the heat exchange efficiency can be enhanced as compared with the case where two fluids of the refrigerant and the heat medium flow in parallel flow inside the condenser 12.

A heater 45 is provided to heat the heat medium from the condenser 12 to the heating heat exchanger 43. Therefore, even if the heat medium can not be sufficiently heated by the condenser 12 when the compressor 11 is not operating, the temperature of the heating heat exchanger 43 is increased by heating the heat medium by the heater 45. It is possible to realize an appropriate heating operation.

In the heating operation, the air conditioning on-off valve 21 is closed, and the battery on-off valve 31 is opened to perform a single operation of battery cooling. In this case, since the heat medium is heated by receiving heat from the high-temperature refrigerant in the condenser 12, the energy consumed by the heater 45 can be reduced. In the condenser 12, the heat medium is heated by the refrigerant having the heat accompanying the compression in the compressor 11 and the heat absorbed from the secondary battery 35. Therefore, the exhaust heat of the secondary battery 35 can be indirectly used in the heating operation.

The object to be cooled is the secondary battery 35 that supplies power to the vehicle. For this reason, when a large current flows in power supply and charge to the vehicle, it is possible to stably cool the secondary battery 35 which tends to have a high temperature. Since the secondary battery 35 is likely to deteriorate when the temperature is too high, it is particularly useful to apply a technology that can stably maintain the cooling.

Second Embodiment This embodiment is a modification based on the preceding embodiment. In this embodiment, an auxiliary cooling flow passage 240 for cooling the secondary battery 35 is provided.

In FIG. 6, the vehicle cooling system 1 includes an auxiliary cooling flow channel 240 for cooling the secondary battery 35. The auxiliary cooling flow path 240 is a flow path which is independent of the common flow path 10, the air conditioning flow path 20, and the battery flow path 30 which constitute the refrigeration cycle. The heat medium flowing through the auxiliary cooling flow path 240 is, for example, a liquid such as water or antifreeze liquid.

The auxiliary cooling flow path 240 includes an auxiliary cooling pump 241, an auxiliary cooling heat exchanger 243, an auxiliary cooling reservoir tank 244, and an auxiliary cooling radiator 245. The auxiliary cooling pump 241 is a device that causes the heat medium to flow through the auxiliary cooling flow path 240. The auxiliary cooling reservoir tank 244 is a device that adjusts the pressure so that the pressure in the auxiliary cooling flow path 240 does not increase excessively even when the volume of the heat transfer medium increases as the temperature rises. The auxiliary cooling heat exchanger 243 is a device that exchanges heat between the heat medium flowing inside and the secondary battery 35. The auxiliary cooling heat exchanger 243 is provided in direct contact with the secondary battery 35. The auxiliary cooling radiator 245 is a device that radiates the heat of the heat medium circulating through the auxiliary cooling flow path 240 into the air to cool the heat medium.

In the battery cooling operation for cooling the secondary battery 35, the heat medium is caused to flow to the auxiliary cooling flow path 240 by operating the auxiliary cooling pump 241. In the auxiliary cooling radiator 245, the heat transfer medium exchanges heat with the ambient air to reduce the temperature of the heat transfer medium.

The heat medium whose temperature has been lowered by the auxiliary cooling radiator 245 flows into the auxiliary cooling heat exchanger 243. In the auxiliary cooling heat exchanger 243, the heat medium flowing inside is heat exchanged between the secondary battery 35 to cool the secondary battery 35. The heat medium that has passed through the auxiliary cooling heat exchanger 243 flows into the auxiliary cooling reservoir tank 244 and is then sucked into the auxiliary cooling pump 241 again to repeat a series of circulations.

Cooling of the secondary battery 35 using the auxiliary cooling flow passage 240 can be performed at any timing. For example, by performing cooling using the auxiliary cooling flow passage 240 while performing a cooling operation while circulating the refrigerant in the battery flow passage 30 and using the battery heat exchanger 33 as a cooling source, 2 The secondary battery 35 may be cooled by using two cooling sources in combination. Alternatively, the secondary battery 35 may be cooled using only the auxiliary cooling flow passage 240 in a state where the refrigerant is not flowing in the battery flow passage 30.

According to the embodiment described above, it is possible to cool the secondary battery 35 by independently using two heat exchangers of the battery heat exchanger 33 and the auxiliary cooling heat exchanger 243. Therefore, the secondary battery 35 can be cooled more quickly than when the battery cooling operation is performed only by the battery heat exchanger 33. Furthermore, by securing the time to cool the secondary battery 35 only by the cooling by the auxiliary cooling heat exchanger 243, the time to drive the compressor 11 can be shortened only for the purpose of flowing the refrigerant into the battery heat exchanger 33. . Therefore, the energy required for cooling the secondary battery 35 can be easily reduced.

Third Embodiment This embodiment is a modification based on the preceding embodiment. In this embodiment, the secondary battery 35 is directly cooled by the battery heat exchanger 33. In addition, a device flow path 330 for cooling the device for automatic operation 335 which is a cooling target different from the secondary battery 35 is provided.

In FIG. 7, the battery heat exchanger 33 is provided to be in direct contact with the secondary battery 35. In other words, the secondary battery 35 is cooled by the battery heat exchanger 33 not by indirect cooling using a blower but by direct cooling. In the battery heat exchanger 33, the refrigerant heats off by taking away the heat of vaporization from not only the surrounding air but also the secondary battery 35 in direct contact.

The vehicle cooling system 1 includes a device flow path 330 in parallel with the battery flow path 30. The device flow path 330 is a refrigerant flow path for cooling an automatic driving device 335 which is an electronic device used for control of automatic driving of a vehicle. The automatic driving device 335 is an electronic device that performs operation control during automatic driving. The automatic driving device 335 is a heat generating component that generates heat when performing operation control. In particular, when the operation control is performed for a long time, a large amount of heat is generated and the temperature is likely to rise, so that it is particularly useful to apply a technique capable of stably maintaining the cooling.

The device flow path 330 is a flow path connecting the downstream side of the outdoor heat exchanger 13 and the suction side of the compressor 11 in the common flow path 10 as in the battery flow path 30. The device flow path 330 includes a device on-off valve 331, a device expansion valve 332, and a device heat exchanger 333. The device on-off valve 331 is a valve device that switches between a state in which the refrigerant flows and a state in which the refrigerant does not flow to the device channel 330. The device expansion valve 332 is a valve device that expands the refrigerant flowing through the device flow path 330. In other words, the device expansion valve 332 is a pressure reducing device that causes the refrigerant to have a pressure difference before and after passing through the device expansion valve 332 to facilitate evaporation of the refrigerant. The device heat exchanger 333 is a device that performs heat exchange between the refrigerant and the device for automatic operation 335 which is an object to be cooled. The device heat exchanger 333 is a cooling source that removes the heat of vaporization from the surroundings by evaporating the refrigerant inside. The device heat exchanger 333 is in direct contact with the device for automated operation 335, and the device heat exchanger 333 cools the device for automated operation 335 by direct cooling. The instrument channel 330 provides a cooling channel. The device on-off valve 331 provides a cooling on-off valve. The device heat exchanger 333 provides a cooling heat exchanger. The autonomous driving device 335 provides an object to be cooled.

In the cooling system 1 for vehicles, you may provide another refrigerant flow path in parallel other than the flow path 330 for apparatuses. Also, two battery heat exchangers 33 may be provided in parallel to one secondary battery 35.

According to the embodiment described above, the battery heat exchanger 33 cools the secondary battery 35 by direct cooling. For this reason, the secondary battery 35 can be cooled more quickly than in the case of indirect cooling. Moreover, since it is not necessary to send a wind, the battery duct 3 and the battery blower 36 can be omitted. For this reason, it is easy to miniaturize the cooling system 1 for vehicles.

A device flow path 330 is provided in parallel with the battery flow path 30. For this reason, even when there are a plurality of objects to be cooled, the necessary cooling can be sustained individually by stably maintaining the operation of the refrigeration cycle.

Fourth Embodiment This embodiment is a modification based on the preceding embodiment. In this embodiment, a three-way valve 421 is provided in place of the air conditioning on-off valve 21 and the battery on-off valve 31.

In FIG. 8, a three-way valve 421 is provided at a connection portion between the common flow passage 10, the air conditioning flow passage 20, and the battery flow passage 30. The three-way valve 421 has a function of two valve devices of the air conditioning on-off valve 21 and the battery on-off valve 31. That is, it has a function of switching between a state in which the refrigerant flows and a state in which the refrigerant does not flow in the air conditioning channel 20, and a function of switching a state in which the refrigerant flows and does not flow in the battery channel 30.

According to the embodiment described above, the presence or absence of the flow of the refrigerant in the two flow paths of the air conditioning flow path 20 and the battery flow path 30 can be controlled by the three-way valve 421. In other words, in the cooling operation and the battery cooling operation, one three-way valve 421 can control the individual operation, the combined operation, and the operation stop. Therefore, the number of parts in the vehicle cooling system 1 can be reduced.

Fifth Embodiment This embodiment is a modification based on the preceding embodiment. In this embodiment, after confirming the presence or absence of the air conditioning operation request, the magnitude relationship between the ambient temperature and the lower limit temperature is not determined if the air conditioning operation request is not made, and if there is the air conditioning operation request, the ambient temperature and the lower limit The magnitude relationship with the temperature is determined.

With respect to the flow of control in the cooling operation of the vehicle cooling system 1 of the present embodiment, parts different from the above-described embodiment will be described below. In FIG. 9, the operation of the vehicle cooling system 1 is started, the lower limit temperature is calculated in step S101, and the ambient temperature of the air conditioning heat exchanger 23 is measured in step S102. Then, the process proceeds to step S510.

In step S510, it is determined about the presence or absence of the air conditioning operation request. The state in which the air conditioning operation request is made is a state in which the occupant turns on the air conditioning switch 29 and it is necessary to bring the temperature in the vehicle compartment close to the air conditioning target temperature. In other words, the state in which the air conditioning operation request is made is a state in which the compressor 11 of the vehicle cooling system 1 needs to be driven to perform the air conditioning operation in the vehicle compartment. On the other hand, the state where there is no air conditioning operation request is a state where there is no need to bring the temperature of the vehicle interior closer to the air conditioning target temperature, such as when the air conditioning switch 29 is turned off by the occupant. In other words, the state where there is no air conditioning operation request is a state where there is no need to drive the compressor 11 of the vehicle cooling system 1 in order to perform the air conditioning operation of the vehicle interior. If there is an air conditioning operation request, the process proceeds to step S511. On the other hand, when there is no air conditioning operation request, the process proceeds to step S513.

In step S511, it is determined whether the measured ambient temperature is a temperature equal to or higher than the lower limit temperature. If the ambient temperature is equal to or higher than the lower limit temperature, it is determined that the air around the air conditioning heat exchanger 23 has sufficient heat to evaporate the refrigerant, and the process proceeds to step S512. On the other hand, if the ambient temperature is less than the lower limit temperature, it is determined that the air around the air conditioning heat exchanger 23 does not have sufficient heat for evaporation of the refrigerant, and the process proceeds to step S513.

In step S512, the air conditioning on-off valve 21 is opened. That is, the refrigerant can be circulated to the air conditioning channel 20. On the other hand, in step S513, the air conditioning on-off valve 21 is closed. That is, the refrigerant can not circulate in the air conditioning channel 20. Thus, in a state where there is a high possibility that an operation failure due to a liquid back phenomenon or the like is caused in the refrigeration cycle, the state of the air conditioning on-off valve 21 is switched so as not to circulate the refrigerant. After the air conditioning valve 21 is opened or closed, the process proceeds to step S521.

In step S 521, it is determined whether there is a battery cooling request indicating whether the secondary battery 35 needs to be cooled. If there is a battery cooling request for the secondary battery 35, it is determined that the secondary battery 35 needs to be cooled, and the process proceeds to step S522. On the other hand, when there is no battery cooling request for the secondary battery 35, it is determined that the secondary battery 35 does not need to be cooled, and the process proceeds to step S523.

In step S522, the on-off valve 31 for battery is opened. That is, the refrigerant is allowed to circulate in the battery channel 30. In step S523, the on-off valve 31 is closed. That is, the refrigerant can not be circulated to the battery channel 30. Here, when both valve devices of the air conditioning on-off valve 21 and the battery on-off valve 31 are simultaneously closed, the operation of the compressor 11 is stopped. This prevents the refrigerant pressure from becoming abnormally high in the refrigerant circulation channel. However, the compressor 11 is driven when there is no abnormal high pressure due to the operation of the compressor 11 such as the presence of a flow path through which the refrigerant can circulate other than the air conditioning flow path 20 and the battery flow path 30. The state may be maintained. After the on / off valve 31 for battery is opened or closed, the process returns to step S101 again to repeat a series of control.

According to the embodiment described above, after determining the presence or absence of the air conditioning operation request, the control unit 50 compares the ambient temperature with the lower limit temperature only when there is the air conditioning operation request. Therefore, when there is no air conditioning operation request, the air conditioning on-off valve 21 can be switched to the closed state without comparing the ambient temperature with the lower limit temperature. Therefore, it is possible to quickly switch the air conditioning on / off valve 21 to the closed state. In addition, even when there is no air conditioning operation request, the operation of the vehicle cooling system 1 can be started. In other words, the operation control of the vehicle cooling system 1 can be performed using the same control flow even in the case of performing the single operation of battery cooling or the like.

Instead of determining the presence or absence of the air conditioning operation request after measuring the ambient temperature in step S102, the presence or absence of the air conditioning operation request may be determined before calculating the lower limit temperature in step S101. According to this, after determining the presence or absence of the air conditioning operation request, the control unit 50 performs calculation of the lower limit temperature and measurement of the ambient temperature only when there is the air conditioning operation request. Therefore, when there is no air conditioning operation request, the process can proceed to step S513 without performing control such as calculation of the lower limit temperature. Therefore, when there is no air conditioning operation request, the calculation of the lower limit temperature and the like can be omitted, and the process can quickly shift to the next step. In other words, the on-off valve 21 for air conditioning and the on-off valve 31 for battery can be quickly switched to the appropriate state.

Other Embodiments The disclosure in this specification is not limited to the illustrated embodiments. The disclosure includes the illustrated embodiments and variations based on them by those skilled in the art. For example, the disclosure is not limited to the combination of parts and / or elements shown in the embodiments. The disclosure can be implemented in various combinations. The disclosure can have additional parts that can be added to the embodiments. The disclosure includes those in which parts and / or elements of the embodiments have been omitted. The disclosure includes replacements or combinations of parts and / or elements between one embodiment and another embodiment. The disclosed technical scope is not limited to the description of the embodiments.

Although the disclosure has been described with reference to examples, it is understood that the disclosure is not limited to the disclosed examples or structures. Rather, the present disclosure includes various modifications and variations within the equivalent range. In addition, although various elements of the present disclosure are illustrated by various combinations and forms, other combinations and forms including more elements, fewer elements, or only one of these elements Are also within the scope and scope of the present disclosure.

Claims

A common flow path (10) through which the refrigerant flows by connecting the compressor (11) and the outdoor heat exchanger (13);
An air conditioning heat exchanger (23) used when air conditioning the interior of the vehicle;
An air conditioning flow path (20) connected to the common flow path to provide a flow path through which the refrigerant flows to the air conditioning heat exchanger;
An air conditioning on-off valve (21, 421) provided in the air conditioning channel to control the amount of refrigerant flowing into the air conditioning heat exchanger;
A cooling heat exchanger (33, 333) used to cool an object (35, 335) mounted on the vehicle;
A cooling channel (30, 330) connected to the common channel to provide a channel through which the refrigerant flows to the cooling heat exchanger;
A cooling on-off valve (31, 331, 421) provided in the cooling channel to control the amount of refrigerant flowing into the cooling heat exchanger;
An air conditioning blower (26) for blowing air to the air conditioning heat exchanger;
A temperature sensor (27) provided upstream of the air conditioning heat exchanger in the flow of air from the air conditioning blower;
When there is a demand for cooling the object to be cooled, and the ambient temperature measured by the temperature sensor is lower than a lower limit temperature set to a temperature higher than the evaporation temperature of the refrigerant in the air conditioning heat exchanger. And a control unit (50) for closing the air conditioning on-off valve and opening the cooling on-off valve.
It has an inside / outside air switching door (25) which switches between an outside air introduction mode in which the air flowed to the air conditioning heat exchanger is outside air and an inside air circulation mode in which inside air is made.
The vehicle cooling system according to claim 1, wherein the control unit sets the lower limit temperature higher than the inside air circulation mode when the inside / outside air switching door is in the outside air introduction mode.
A heating channel (40) through which the heat medium flows by connecting the pump (41) and the heating heat exchanger (43);
The condenser (12) for heat exchange between the heat medium flowing through the heating flow path and the refrigerant flowing through the common flow path from the compressor toward the outdoor heat exchanger The vehicle cooling system according to 2.
The vehicle cooling system according to claim 3, further comprising: a heater (45) for heating a heat medium traveling from the condenser toward the heating heat exchanger in the heating flow path.
The vehicle according to claim 3 or 4, wherein in the heating operation in which the heat medium flows in the heating flow path, the cooling operation is performed with the air conditioning on-off valve closed and the cooling on-off valve open. Cooling system.
The vehicle cooling system according to any one of claims 3 to 5, wherein, in the condenser, the heat medium flowing through the heating flow passage and the refrigerant flowing through the common flow passage flow in directions opposite to each other.
The vehicle cooling system according to any one of claims 1 to 6, wherein the object to be cooled is a secondary battery (35) for supplying power to the vehicle.