Heat medium circulation device for vehicle

Abstract

To provide a heat medium circulation device for a vehicle which can restrain electrical power consumption when air-conditioning is used.SOLUTION: A heat medium circulation device for a vehicle comprises a heating circuit around which a first heat transfer medium supplied to a heater core is circulated, a battery temperature control circuit around which a second heat transfer medium supplied to a battery is circulated, a circuit switching valve which switches connection state between the heating circuit and the battery temperature control circuit and a controller which controls the heating circuit, the battery temperature control circuit and the circuit switching valve. The controller includes a prediction part which predicts start of air-conditioning during stop of the air-conditioning and a switching control part which controls the circuit switching valve on the basis of determination result of the prediction part. The switching control part makes the circuit switching valve to opening communication state so that the second heat transfer medium of the battery temperature control circuit is sent to the heating circuit if the prediction part predicts the start of the air-conditioning.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a heat medium circulating device for a vehicle including a heating circuit through which a first heat medium supplied to a heater core is circulated, and a battery temperature regulating circuit through which a second heat medium supplied to a battery is circulated. [Background technology]

[0002] An electric vehicle (BEV: Battery Electric Vehicle) runs by driving a motor with power from a battery. Since a BEV does not have an engine, it cannot use the exhaust heat of the engine for heating. Therefore, electric vehicles use an electric heating device such as a heater or a heat pump as a heat source for air conditioning.

[0003] Patent document 1 discloses a refrigerant circulation device for a vehicle that includes a battery temperature adjustment cycle that adjusts the temperature of a battery, an air conditioning cycle that adjusts the temperature inside the vehicle cabin, and a connection means that connects in parallel a first coolant flow path of the battery temperature adjustment cycle and a second coolant flow path of the air conditioning cycle.

[0004] Patent Document 2 discloses a vehicle air conditioner that, when it is predicted that a passenger will board the vehicle, performs a heating preparation operation by heating a heat medium to be supplied to a heater core with a heating device before the passenger boards the vehicle. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2015-93561 A [Patent Document 2] JP 2017-100476 A Summary of the Invention [Problem to be solved by the invention]

[0006] In general, in a conventional electric vehicle, when the air conditioning is stopped, the heat medium supplied to the heater core is not heated. After the air conditioning is started, the heat medium is heated by a heating device to raise the temperature of the heater core to a target temperature. When the air conditioning is stopped, the heat medium is not heated, so the temperature of the heat medium is low. For example, the temperature of the heat medium is close to the outside air temperature. When the air conditioning is started from a stopped state, the heat medium is heated from a low temperature state to the target temperature in one go, so the power consumption of the heating device is large. Since the heating device consumes a lot of battery power, the cruising distance of the electric vehicle is shortened. In addition, it takes a long time to heat the heater core to the target temperature.

[0007] An object of the present invention is to provide a heat medium circulating device for a vehicle that can reduce power consumption when air conditioning is in use. [Means for solving the problem]

[0008] A heat medium circulation device for a vehicle according to one embodiment of the present invention includes a heating circuit through which a first heat medium supplied to a heater core is circulated, a battery temperature adjustment circuit through which a second heat medium supplied to a battery is circulated, a circuit switching valve that switches a connection state between the heating circuit and the battery temperature adjustment circuit, and a controller that controls the heating circuit, the battery temperature adjustment circuit, and the circuit switching valve, wherein the controller has a prediction unit that predicts the start of air conditioning while air conditioning is stopped, and a switching control unit that controls the circuit switching valve based on a determination result of the prediction unit, and when the prediction unit predicts the start of air conditioning, the switching control unit opens the circuit switching valve so that the second heat medium in the battery temperature adjustment circuit is sent to the heating circuit. Effect of the Invention

[0009] When the start of air conditioning is predicted while air conditioning is stopped, the above-mentioned heat medium circulation device for a vehicle opens the circuit switching valve so that the second heat medium in the battery temperature adjustment circuit is sent to the heating circuit. By mixing the second heat medium with the first heat medium in the heating circuit, the first heat medium can be heated or cooled by the second heat medium. Thus, the above-mentioned heat medium circulation device for a vehicle can preliminarily heat or cool the heater core.

[0010] For example, while the vehicle is running, the battery generates heat through discharge, causing the temperature of the second heat medium in the battery temperature adjustment circuit to rise. When the temperature of the second heat medium is higher than that of the first heat medium, the first heat medium is heated by the second heat medium, and the heater core can be preliminarily heated. When air conditioning is started, the first heat medium is preliminarily heated, so that the power consumption for heating the heater core to the target temperature is reduced. In addition, the time required to heat the heater core to the target temperature is shortened. Since the heater core is preliminarily heated using the exhaust heat of the battery, the power consumption used for heating the heater core to the target temperature is reduced. Therefore, the above-mentioned vehicle heat medium circulating device can reduce power consumption when air conditioning is used. [Brief description of the drawings]

[0011] [Figure 1] FIG. 1 is a schematic diagram showing a configuration of a heat medium circulating device for a vehicle according to an embodiment. [Diagram 2] FIG. 2 is a schematic enlarged view for explaining a circuit switching valve provided in the heat medium circulating device for a vehicle according to the embodiment. [Diagram 3] FIG. 3 is a flowchart showing an example of a control procedure by the controller in the heat medium circulating device for a vehicle according to the embodiment. [Figure 4] FIG. 4 is a flowchart showing another example of the control procedure by the controller in the heat medium circulating device for a vehicle according to the embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] A specific example of a heat medium circulating device for a vehicle according to an embodiment of the present invention will be described with reference to the drawings. In each drawing, the same or corresponding parts are given the same reference numerals. The sizes of the members shown in each drawing are expressed for the purpose of clarifying the description, and do not necessarily represent the actual dimensions.

[0013] <Heat medium circulator for vehicles> An electric vehicle 1 equipped with a heat medium circulator 1A for a vehicle according to an embodiment will be described with reference to Fig. 1. The electric vehicle 1 is equipped with a battery 10 and an air conditioning unit 2. The electric vehicle 1 is an automobile that runs by driving a motor (not shown) with power from the battery 10. In this example, the electric vehicle 1 is a BEV. The electric vehicle 1 may also be, for example, a HEV (Hybrid Electric Vehicle) or a FCEV (Fuel Cell Electric Vehicle).

[0014] As shown in FIG. 1, the heat medium circulating device 1A for a vehicle according to the embodiment includes a heating circuit 3 and a battery temperature adjustment circuit 6. The heating circuit 3 circulates a first heat medium supplied to a heater core 26 of an air conditioning unit 2. The battery temperature adjustment circuit 6 circulates a second heat medium supplied to a battery 10. The heat medium circulating device 1A for a vehicle according to the present embodiment further includes a heat pump circuit 4. The heat pump circuit 4 circulates a third heat medium. In FIG. 1, the outline arrows indicate the respective flow directions of the first heat medium, the second heat medium, and the third heat medium. One of the features of the heat medium circulating device 1A for a vehicle according to the embodiment is that it includes a circuit switching valve 7 and a controller 5 that performs specific control. The configuration of the heat medium circulating device 1A for a vehicle will be described in detail below.

[0015] (Battery) The battery 10 is a secondary battery used as a power source for driving the motor of the electric vehicle 1. The battery 10 supplies power to the motor and also to various electrical devices mounted on the electric vehicle 1. The battery 10 generates heat by charging and discharging. The battery 10 of this example has a flow path through which the second heat medium of the battery temperature adjustment circuit 6 flows. The temperature of the battery 10 is adjusted by heat exchange between the battery 10 and the second heat medium. The battery 10 of this example is provided with a battery temperature sensor 10t that detects the temperature of the battery 10. The battery 10 is arranged, for example, at the bottom of the electric vehicle 1.

[0016] (Air conditioning unit) The air conditioning unit 2 is a device that conditions the air inside the vehicle cabin. The air conditioning unit 2 is also called an HVAC (Heating, Ventilation and Air Conditioning) unit. The air conditioning unit 2 adjusts the temperature of air taken in from an inlet 2i and sends the temperature-adjusted air from an outlet 2o into the vehicle cabin.

[0017] The air conditioning unit 2 has a heater core 26, an evaporator 27, an air mix door 28, and a blower 29. In the air conditioning unit 2, the evaporator 27, the air mix door 28, and the heater core 26 are arranged in this order from the inlet 2i toward the outlet 2o. The blower 29 draws in air from the inlet 2i and blows the drawn air toward the outlet 2o. The output of the blower 29 is adjusted to adjust the volume of air blown out from the outlet 2o.

[0018] The evaporator 27 is a component that cools air. A third heat medium is supplied to the evaporator 27 from the heat pump circuit 4 described later. The third heat medium supplied to the evaporator 27 expands by the cooling expansion valve 46 and becomes low temperature and low pressure. The cooling expansion valve 46 is, for example, an electric expansion valve. By supplying the low-temperature third heat medium to the evaporator 27, the evaporator 27 becomes low temperature, and the air passing through the evaporator 27 is cooled. The temperature of the third heat medium that has passed through the evaporator 27 increases due to heat exchange with the air. The evaporator 27 is provided with an evaporator temperature sensor 27t. The evaporator temperature sensor 27t may be one that detects the temperature of the air around the evaporator 27, or one that detects the temperature of the third heat medium supplied to the evaporator 27.

[0019] The heater core 26 is a component that heats air. The heater core 26 is disposed downstream of the evaporator 27. The first heat medium of the heating circuit 3 is supplied to the heater core 26. By supplying the high-temperature first heat medium to the heater core 26, the heater core 26 becomes hot, and the air passing through the heater core 26 is heated. The temperature of the first heat medium that has passed through the heater core 26 is reduced by heat exchange with the air.

[0020] The air mix door 28 is a component that adjusts the ratio of air passing through the heater core 26 to air bypassing the heater core 26. The air mix door 28 is disposed between the evaporator 27 and the heater core 26. When the air mix door 28 is open, the air that has passed through the evaporator 27 passes through the heater core 26. When the air mix door 28 is closed, the air that has passed through the evaporator 27 bypasses the heater core 26. When the air mix door 28 is open, the ratio of air passing through the heater core 26 increases. When the air mix door 28 is closed, the ratio of air passing through the heater core 26 decreases. By adjusting the opening degree of the air mix door 28, the air cooled by the evaporator 27 and the air heated by the heater core 26 are mixed, and the temperature of the air blown out from the air outlet 2o is adjusted. The air outlet 2o is provided with an air outlet temperature sensor 25 that detects the temperature of the air blown out from the air outlet 2o.

[0021] (Heating circuit) The heating circuit 3 is used to heat the heater core 26 when the air conditioning is ON. The heating circuit 3 is also used to heat a second heat medium in the battery temperature adjustment circuit 6 described later in order to heat the battery 10. The heating circuit 3 of this example has a pump 31 that circulates a first heat medium and a heater 32 that heats the first heat medium. The first heat medium is a cooling water such as a long-life coolant (LLC). The pump 31 is, for example, an electric water pump. The heater 32 is an electric heater such as a high-voltage heater (HVH: High Voltage Heater). The heating circuit 3 of this example is configured with a flow path such that the first heat medium sent from the pump 31 returns to the pump 31 via the heater 32 and the heater core 26. When the pump 31 is operated, the first heat medium circulates through the heating circuit 3, and the first heat medium is supplied to the heater core 26. The heater core 26 is heated by heating the first heat medium by one or both of the heater 32 and the heat pump circuit 4 described later. When the air conditioning is OFF, that is, when the heater core 26 is not heated, the pump 31 and the heater 32 are stopped, and the heated first heat medium is not supplied to the heater core 26.

[0022] The heating circuit 3 of this example is provided with a first temperature sensor 35a and a second temperature sensor 35b. The first temperature sensor 35a detects the temperature of the first heat medium supplied to the heater core 26. The first temperature sensor 35a is provided in a flow path between the heater 32 and the heater core 26. The second temperature sensor 35b detects the temperature of the first heat medium that has passed through the heater core 26. The second temperature sensor 35b is provided in a flow path between the heater core 26 and the pump 31.

[0023] The heating circuit 3 may be provided with a reserve tank 33. The reserve tank 33 is a tank for temporarily storing the first heat medium that overflows from the heating circuit 3 due to thermal expansion caused by a temperature rise of the first heat medium. The reserve tank 33 also has a function of separating air bubbles generated in the heating circuit 3. The reserve tank 33 separates the first heat medium and air bubbles in the heating circuit 3 and removes the air bubbles in the heating circuit 3, thereby making it possible to keep the pressure in the heating circuit 3 stable. In this example, the reserve tank 33 is connected in series to the heating circuit 3. The reserve tank 33 is disposed in a flow path between the heater core 26 and the pump 31.

[0024] The heating circuit 3 of this example is capable of heating the first heat medium in the heating circuit 3 by the heat pump circuit 4, which will be described later in detail. The heating circuit 3 of this example includes a heat exchanger 34 that performs heat exchange between the first heat medium and a third heat medium flowing through the heat pump circuit 4, which will be described later. The heat exchanger 34 has a first heat exchange section 34a through which the first heat medium flows and a second heat exchange section 34b through which the third heat medium flows. The first heat exchange section 34a and the second heat exchange section 34b are thermally connected to each other, so that heat exchange is performed between the first heat medium and the third heat medium. The heat exchanger 34 is, for example, a water-cooled condenser. The heat exchanger 34 is disposed in a flow path between the pump 31 and the heater 32. As long as the first heat medium can be heated by the heat pump circuit 4 as in this example, the heater 32 is not an essential component.

[0025] The heating circuit 3 of this example is connected to the heat pump circuit 4 by the heat exchanger 34, and the first heat medium in the heating circuit 3 can be heated by the heat exchanger 34. Therefore, the heating circuit 3 of this example can raise the temperature of the heater core 26 only by the heat pump circuit 4, even if the heater 32 is not operating. Furthermore, the heating circuit 3 of this example can also heat the first heat medium by the heat pump circuit 4 and the heater 32. When the heater core 26 cannot be sufficiently raised in temperature only by the heat pump circuit 4, the heater core 26 can be raised in temperature by both the heat pump circuit 4 and the heater 32.

[0026] (Heat pump circuit) The heat pump circuit 4 is used when the first heat medium in the heating circuit 3 is heated by the heat exchanger 34 when the heater core 26 is heated. The heat pump circuit 4 is also used to cool the evaporator 27 when the air conditioning is ON. Furthermore, the heat pump circuit 4 of this example is also used to cool the second heat medium in the battery temperature adjustment circuit 6 described later in order to cool the battery 10. The heat pump circuit 4 of this example has a compressor 41, a condenser 42, a heating expansion valve 44, and a cooling expansion valve 46. The heat pump circuit 4 of this example has a flow path configured so that the third heat medium discharged from the compressor 41 is sent to the condenser 42 via the heat exchanger 34 and the heating expansion valve 44 of the heating circuit 3. The third heat medium has the property of becoming hot when compressed and becoming cold when expanded. The third heat medium is, for example, hydrofluorocarbon (HFC).

[0027] The compressor 41 compresses and discharges the low-pressure third heat medium sent from the accumulator 45. The compressor 41 is, for example, an electric compressor. The third heat medium compressed to a high temperature and high pressure by the compressor 41 is sent to the heat exchanger 34. The heat exchanger 34 is disposed in a flow path between the compressor 41 and the heating expansion valve 44.

[0028] The heat exchanger 34 exchanges heat between the high-temperature third heat medium sent from the compressor 41 and the first heat medium of the heating circuit 3. The high-temperature third heat medium flows through the second heat exchange section 34b, thereby heating the first heat medium in the first heat exchange section 34a. The first heat medium circulating through the heating circuit 3 is heated, thereby raising the temperature of the heater core 26. The temperature of the third heat medium that has passed through the heat exchanger 34 is reduced by heat exchange with the first heat medium.

[0029] The third heat medium discharged from the heat exchanger 34 is sent to the condenser 42 through the heating expansion valve 44. The third heat medium is expanded by the heating expansion valve 44 and becomes low temperature and low pressure. The heating expansion valve 44 is, for example, an electric expansion valve.

[0030] The condenser 42 is a device that exchanges heat between the third heat medium in the heat pump circuit 4 and outside air. The condenser 42 is disposed outside the vehicle compartment. Outside air is taken in from the front grille 12 by the fan 11. When the outside air hits the condenser 42, heat is exchanged between the third heat medium flowing through the condenser 42 and the outside air.

[0031] The heat pump circuit 4 of this example has a first flow path 4a, a second flow path 4b, and a third flow path 4c. The first flow path 4a is a flow path that sends the third heat medium from the condenser 42 to the evaporator 27. The first flow path 4a is used when cooling the evaporator 27, that is, when the air conditioning is ON. The second flow path 4b is a flow path that sends the third heat medium from the condenser 42 to a chiller 62 of the battery temperature adjustment circuit 6 described later. The second flow path 4b is used when cooling the battery 10. The third flow path 4c is a bypass flow path that returns the third heat medium from the condenser 42 to the compressor 41. The third flow path 4c is used when the evaporator 27 is not cooled and when the battery 10 is not cooled. The flow paths are switched by the switching valve 40. The switching valve 40 is, for example, an electromagnetic valve. When the switching valve 40 is closed, the third heat medium discharged from the condenser 42 flows toward the first flow path 4a and the second flow path 4b. When the switching valve 40 is open, the third heat medium flows through the third flow path 4c.

[0032] When the evaporator 27 is cooled or when the battery 10 is cooled, the switching valve 40 is closed. When the evaporator 27 is cooled, the third heat medium flows through the first flow path 4a. The third heat medium is sent to the evaporator 27 through the first flow path 4a and then returned to the compressor 41. The third heat medium is expanded by the cooling expansion valve 46 before the evaporator 27 and is supplied to the evaporator 27 in a low-temperature, low-pressure state. When the evaporator 27 is not cooled, the cooling expansion valve 46 is closed and the third heat medium does not flow through the first flow path 4a. In other words, the third heat medium is not supplied to the evaporator 27.

[0033] When the battery 10 is cooled, the third heat medium flows through the second flow path 4b. The third heat medium is sent to the chiller 62 through the second flow path 4b, and then returned to the compressor 41. The third heat medium is expanded by the chiller expansion valve 49 before the chiller 62, and is supplied to the chiller 62 in a low-temperature, low-pressure state. The chiller 62 will be described later. When the battery 10 is not cooled, the chiller expansion valve 49 is closed, and the third heat medium does not flow through the second flow path 4b. In other words, the third heat medium is not supplied to the chiller 62.

[0034] When the evaporator 27 and the battery 10 are not cooled, the switching valve 40 is opened and the third heat medium is returned to the compressor 41 through the third flow path 4c. In this case, the third heat medium does not flow through the first flow path 4a and the second flow path 4b.

[0035] The third heat medium returned to the compressor 41 through any one of the first flow path 4a, the second flow path 4b, and the third flow path 4c is recovered in the accumulator 45. The accumulator 45 separates the liquefied third heat medium and supplies only the vaporized third heat medium to the compressor 41.

[0036] The heat pump circuit 4 of this example is provided with a first temperature sensor 47a, a second temperature sensor 47b, a third temperature sensor 47c, a fourth temperature sensor 47d, and a pressure sensor 48. The first temperature sensor 47a detects the temperature of the third heat medium sent from the compressor 41 to the heat exchanger 34. The second temperature sensor 47b detects the temperature of the third heat medium discharged from the heat exchanger 34. The third temperature sensor 47c detects the temperature of the third heat medium discharged from the condenser 42. The fourth temperature sensor 47d detects the temperature of the third heat medium passed through the evaporator 27. The fifth temperature sensor 47e detects the temperature of the third heat medium discharged from the chiller 62. The pressure sensor 48 detects the pressure of the third heat medium discharged from the heat exchanger 34. The second temperature sensor 47b and the pressure sensor 48 are disposed in a flow path between the heat exchanger 34 and the heating expansion valve 44.

[0037] (Battery temperature adjustment circuit) The battery temperature adjustment circuit 6 is a circuit that adjusts the temperature of the battery 10 using a second heat medium in order to maintain the temperature of the battery 10 within a predetermined range. The temperature of the battery 10 is adjusted by heat exchange between the second heat medium and the battery 10. The battery 10 deteriorates when it becomes hot. The performance of the battery 10 decreases when it becomes cold. The above-mentioned predetermined temperature range means the operating temperature range in which the battery 10 operates safely and efficiently. The operating temperature range of the battery 10 depends on the specifications of the battery. The operating temperature range of the battery 10 is, for example, from 0°C to 40°C.

[0038] The battery temperature regulation circuit 6 includes a temperature regulation device that changes the temperature of the second heat medium to regulate the temperature of the battery 10. The second heat medium is cooled, thereby cooling the battery 10. The second heat medium is heated, thereby raising the temperature of the battery 10. As described below, in this example, the cooling of the battery 10 is achieved by a chiller 62 provided in the battery temperature regulation circuit 6. Also, the heating of the battery 10 is achieved by the heating circuit 3 and the circuit switching valve 7. That is, in the battery temperature regulation circuit 6, the chiller 62 functions as a part of the temperature regulation device for cooling the second heat medium. Also, the heating circuit 3 and the circuit switching valve 7 function as a part of the temperature regulation device for heating the second heat medium.

[0039] The battery temperature adjustment circuit 6 of this example has a pump 61 that circulates the second heat medium and a chiller 62 that cools the second heat medium. The second heat medium is cooling water such as long-life coolant (LLC). In this example, the second heat medium of the battery temperature adjustment circuit 6 and the first heat medium of the heating circuit 3 are the same. In the battery temperature adjustment circuit 6 of this example, a flow path is configured such that the second heat medium sent out from the pump 61 returns to the pump 61 via the battery 10 and the chiller 62. When the pump 61 is operated, the second heat medium circulates through the battery temperature adjustment circuit 6, and the second heat medium flows through the battery 10. The pump 61 is, for example, an electric water pump.

[0040] The battery temperature adjustment circuit 6 of this example cools the battery 10 by cooling the second heat medium with the chiller 62. The chiller 62 is a heat exchanger that cools the second heat medium using the third heat medium of the heat pump circuit 4 in order to cool the battery 10. The chiller 62 has a first heat exchange section 62a through which the second heat medium flows and a second heat exchange section 62b through which the third heat medium flows. The first heat exchange section 62a and the second heat exchange section 62b are thermally connected to each other, so that heat exchange is performed between the second heat medium and the third heat medium. The low-temperature third heat medium expanded by the above-mentioned cooling expansion valve 46 flows through the second heat exchange section 62b, so that the second heat medium in the first heat exchange section 62a is cooled. The second heat medium circulating in the battery temperature adjustment circuit 6 is cooled, so that the battery 10 is cooled. The temperature of the second heat medium cooled by the chiller 62 is lower than the temperature of the battery 10.

[0041] In the battery temperature adjustment circuit 6 of this example, when the battery 10 is cooled, the pump 61 operates and the second heat medium cooled by the chiller 62 circulates. On the other hand, when the battery 10 is not cooled, the pump 61 is stopped and the second heat medium is not circulated. Furthermore, when the battery 10 is not cooled, the third heat medium of the heat pump circuit 4 is not supplied to the chiller 62 as described above, and therefore the chiller 62 is stopped. Therefore, the second heat medium is not cooled.

[0042] In this example, the chiller 62 is disposed downstream of the battery 10 and cools the second heat medium that has passed through the battery 10. The chiller 62 is provided in the battery temperature adjustment circuit 6, midway through the flow path from the battery 10 to the pump 61. The battery 10 is provided in the battery temperature adjustment circuit 6, midway through the flow path from the pump 61 to the chiller 62. In addition, in order to prevent the pressure of the second heat medium from increasing due to thermal expansion, the battery temperature adjustment circuit 6 in this example is configured to send a portion of the second heat medium to the reserve tank 33 when the pressure of the second heat medium that has passed through the battery 10 reaches a predetermined level or higher.

[0043] The battery temperature adjustment circuit 6 of this example is provided with a temperature sensor 65. The temperature sensor 65 detects the temperature of the second heat medium supplied to the battery 10. The temperature sensor 65 is disposed in a flow path between the pump 61 and the battery 10.

[0044] The battery temperature adjustment circuit 6 of this embodiment does not include a battery heater that heats the second heat medium to increase the temperature of the battery 10.

[0045] (Circuit switching valve) The circuit switching valve 7 is a device that switches the connection state between the heating circuit 3 and the battery temperature regulation circuit 6. In this example, the heating circuit 3 and the battery temperature regulation circuit 6 are connected so that the heat medium can move between the heating circuit 3 and the battery temperature regulation circuit 6 by the circuit switching valve 7. The circuit switching valve 7 allows or blocks the movement of the heat medium. The circuit switching valve 7 is, for example, a solenoid valve.

[0046] The configuration of the circuit switching valve 7 will be described in detail with reference to FIG. 2. The circuit switching valve 7 in this example is a four-way valve that can branch a flow path in four directions. A known four-way valve (for example, JP 2013-238310 A and JP 2020-200902 A) can be used as the four-way valve. The circuit switching valve 7 is not limited to a four-way valve, and may be any valve that can branch a flow path in four or more directions.

[0047] The circuit switching valve 7 of this example is disposed between the heating circuit 3 and the battery temperature adjustment circuit 6, and has four connection ports. The circuit switching valve 7 connects the middle of the heating circuit 3 to the middle of the battery temperature adjustment circuit 6. The connection point of the circuit switching valve 7 in the heating circuit 3 is provided in the middle of the flow path from the heater core 26 to the pump 31, more specifically, in the flow path between the second temperature sensor 35b and the reserve tank 33. Of the four connection ports of the circuit switching valve 7, the first connection port and the second connection port are connected to points A and B of the heating circuit 3, respectively. The connection point of the circuit switching valve 7 in the battery temperature adjustment circuit 6 is provided in the middle of the flow path from the chiller 62 to the pump 61. Of the four connection ports of the circuit switching valve 7, the third connection port and the fourth connection port are connected to points C and D of the battery temperature adjustment circuit 6, respectively.

[0048] When the circuit switching valve 7 is closed, the circuit switching valve 7 is shut off. When the circuit switching valve 7 is shut off, the heating circuit 3 and the battery temperature adjustment circuit 6 are parallel circuits independent of each other. When the circuit switching valve 7 is shut off, the first heat medium of the heating circuit 3 is not sent to the battery temperature adjustment circuit 6, and the second heat medium of the battery temperature adjustment circuit 6 is not sent to the heating circuit 3. In other words, the movement of the heat medium between the heating circuit 3 and the battery temperature adjustment circuit 6 is not possible. When the circuit switching valve 7 is shut off, all of the first heat medium that entered the circuit switching valve 7 from point A of the heating circuit 3 flows from the circuit switching valve 7 to point B of the heating circuit 3. Therefore, the first heat medium circulates through the heating circuit 3 without being sent to the battery temperature adjustment circuit 6 through the circuit switching valve 7. Also, when the circuit switching valve 7 is shut off, all of the second heat medium that entered the circuit switching valve 7 from point C of the battery temperature adjustment circuit 6 flows from the circuit switching valve 7 to point D of the battery temperature adjustment circuit 6. Therefore, the second heat medium circulates through the battery temperature adjustment circuit 6 without passing through the circuit switching valve 7 and being sent to the heating circuit 3 .

[0049] When the circuit switching valve 7 is opened, the circuit switching valve 7 is opened. When the circuit switching valve 7 is opened, the heating circuit 3 and the battery temperature adjustment circuit 6 are connected to form a series circuit. When the circuit switching valve 7 is opened, the first heat medium of the heating circuit 3 is sent to the battery temperature adjustment circuit 6, and the second heat medium of the battery temperature adjustment circuit 6 is sent to the heating circuit 3. That is, the heat medium can move between the heating circuit 3 and the battery temperature adjustment circuit 6. When the circuit switching valve 7 is opened, the first heat medium that entered the circuit switching valve 7 from point A of the heating circuit 3 flows from the circuit switching valve 7 to point D of the battery temperature adjustment circuit 6. Therefore, the first heat medium is sent to the battery temperature adjustment circuit 6 through the circuit switching valve 7 and flows through the battery temperature adjustment circuit 6. Also, when the circuit switching valve 7 is opened, the second heat medium that entered the circuit switching valve 7 from point C of the battery temperature adjustment circuit 6 flows from the circuit switching valve 7 to point B of the heating circuit 3. Therefore, the second heat medium is sent to the heating circuit 3 through the circuit switching valve 7 and flows through the heating circuit 3. That is, when the circuit switching valve 7 is in an open state, the first heat medium in the heating circuit 3 and the second heat medium in the battery temperature adjustment circuit 6 are mixed.

[0050] The opening degree of the circuit switching valve 7 in this example is adjustable. By adjusting the opening degree of the circuit switching valve 7, the amount of heat medium moving between the heating circuit 3 and the battery temperature adjustment circuit 6 can be adjusted. Specifically, the circuit switching valve 7 allows a part of the first heat medium that has entered the circuit switching valve 7 from point A of the heating circuit 3 to flow to point D of the battery temperature adjustment circuit 6, and the remaining part of the first heat medium to flow to point B of the heating circuit 3. In addition, the circuit switching valve 7 allows a part of the second heat medium that has entered the circuit switching valve 7 from point C of the battery temperature adjustment circuit 6 to flow to point B of the heating circuit 3, and the remaining part of the second heat medium to flow to point D of the battery temperature adjustment circuit 6. When the circuit switching valve 7 is fully open, the entire first heat medium that has entered the circuit switching valve 7 from the heating circuit 3 is sent to the battery temperature adjustment circuit 6, and the entire second heat medium that has entered the circuit switching valve 7 from the battery temperature adjustment circuit 6 is sent to the heating circuit 3.

[0051] The battery temperature regulation circuit 6 in this example increases the temperature of the battery 10 by sending the first heat medium of the heating circuit 3 to the battery temperature regulation circuit 6 via the circuit switching valve 7. When increasing the temperature of the battery 10, the pump 61 operates and the heater 32 heats the first heat medium of the heating circuit 3. The first heat medium may be heated by the above-mentioned heat pump circuit 4. The heater 32 and the heat pump circuit 4 may be used in combination to heat the first heat medium.

[0052] When the temperature of the battery 10 is increased, the circuit switching valve 7 is switched to an open state. When the circuit switching valve 7 is in an open state, the first heat medium heated in the heating circuit 3 is sent to the battery temperature adjustment circuit 6. In other words, the second heat medium in the battery temperature adjustment circuit 6 can be heated using the heater 32 or the heat pump circuit 4 of the heating circuit 3, or using the heater 32 and the heat pump circuit 4 in combination. The first heat medium and the second heat medium are mixed to heat the second heat medium. The second heat medium circulating in the battery temperature adjustment circuit 6 is heated, thereby increasing the temperature of the battery 10.

[0053] When raising the temperature of the battery 10, it is sufficient that at least one of the pumps 31 of the heating circuit 3 and the pump 61 of the battery temperature adjustment circuit 6 is operating. When the circuit switching valve 7 is in an open state, the heating circuit 3 and the battery temperature adjustment circuit 6 form a series circuit, so that when at least one of the pumps is operating, the first heat medium flows through the heating circuit 3 and the first heat medium flows through the battery temperature adjustment circuit 6.

[0054] When the temperature of the battery 10 is not being increased, the circuit switching valve 7 is switched to the shutoff state. When the circuit switching valve 7 is in the shutoff state, the first heat medium of the heating circuit 3 is not sent to the battery temperature adjustment circuit 6, and therefore the second heat medium of the battery temperature adjustment circuit 6 is not heated by the first heat medium. In addition, when the temperature of the battery 10 is not being increased, the pump 61 is stopped.

[0055] Furthermore, in the battery temperature regulation circuit 6 of this example, for example, before air conditioning is started, the circuit switching valve 7 is opened and the pump 61 is operated to send the second heat medium to the heating circuit 3, so that the first heat medium of the heating circuit 3 can be preliminarily heated or cooled by the second heat medium. This allows the heater core 26 to be preliminarily heated or cooled. Hereinafter, the control for preliminarily heating or cooling the heater core 26 before air conditioning is started is referred to as preliminarily temperature adjustment control. When the temperature of the second heat medium of the battery temperature regulation circuit 6 is higher than the temperature of the first heat medium of the heating circuit 3, the first heat medium can be warmed by the second heat medium. For example, while the electric vehicle 1 is traveling, the battery 10 generates heat by discharging, and the temperature of the second heat medium rises. When the circuit switching valve 7 is opened, the warm second heat medium is sent to the heating circuit 3. The first heat medium and the second heat medium are mixed to warm the first heat medium. The first heat medium circulating in the heating circuit 3 is warmed, so that the heater core 26 can be warmed. Since the heater core 26 is preliminarily heated by utilizing the exhaust heat of the battery 10 without using the heater 32 or the heat pump circuit 4, the power consumption is small.

[0056] Furthermore, when the temperature of the second heat medium in the battery temperature adjustment circuit 6 is lower than the temperature of the first heat medium in the heating circuit 3, the first heat medium can be cooled by the second heat medium. For example, when the outside air temperature is low, the battery 10 and the second heat medium are cooled by the outside air. When the circuit switching valve 7 is opened, the cold second heat medium is sent to the heating circuit 3. When the first heat medium and the second heat medium are mixed, the first heat medium is cooled. When the first heat medium circulating in the heating circuit 3 is cooled, the heater core 26 can be cooled.

[0057] When the preliminary temperature adjustment control is performed, at least one of the pump 31 of the heating circuit 3 and the pump 61 of the battery temperature adjustment circuit 6 needs to be in operation.

[0058] (Controller) The controller 5 controls the heating circuit 3, the battery temperature adjustment circuit 6, and the circuit switching valve 7. Furthermore, in this example, the controller 5 controls the air conditioning unit 2 and the heat pump circuit 4. The controller 5 in this example is responsible for all controls in the vehicle heat medium circulating device 1A, such as control for performing air conditioning and control for adjusting the temperature of the battery 10. The control for performing air conditioning is control for raising the temperature of the heater core 26 and cooling the evaporator 27. The control for adjusting the temperature of the battery 10 is control for raising or cooling the battery 10 so that the temperature of the battery 10 falls within a predetermined range. Furthermore, the controller 5 in this example performs preliminary temperature adjustment control for preliminarily raising or cooling the heater core 26 before starting air conditioning.

[0059] The controller 5 is configured, for example, by an electronic control unit (ECU). The ECU includes a processor, a memory, a timer, etc. The memory stores a control program to be executed by the processor, and various data, etc. The processor performs various processes such as arithmetic processing and judgment processing required to execute the control program. The controller 5 operates when the processor executes the control program stored in the memory. The above-mentioned multiple processors, which are physically separated, may cooperate with each other to execute the above-mentioned processes.

[0060] The controller 5 has a prediction unit 51 and a switching control unit 52 to perform preliminary temperature adjustment control before starting air conditioning. Before starting air conditioning, the air conditioning is OFF and the heater core 26 is not heated. In other words, the first heat medium is not heated by the heating circuit 3.

[0061] The prediction unit 51 predicts the start of air conditioning while it is stopped. The start of air conditioning can be predicted from, for example, real-time changing weather data such as outside temperature, route information from the departure point to the destination and weather information along the route, and the user's air conditioning operation history. A publicly known method, for example the method described in Patent Document 2, may be used to predict the start of air conditioning. A prediction that a passenger will board the vehicle may be regarded as a prediction of the start of air conditioning.

[0062] For example, when the outside temperature is high or low, there is a high probability that the user will use the air conditioning, i.e., turn on the air conditioning. The outside temperature can be detected by the outside temperature sensor 15. The outside temperature sensor 15 is provided, for example, between the front grille 12 and the condenser 42. The weather data may include, for example, the amount of solar radiation and the amount of rainfall. The amount of solar radiation can be detected by a solar radiation sensor (not shown). The amount of rainfall can be detected by a raindrop sensor (not shown).

[0063] The route information can be acquired, for example, from a navigation system (not shown) mounted on the electric vehicle 1. Weather information along the route can be acquired, for example, from a weather forecast including the weather, temperature, and probability of precipitation. For example, when the electric vehicle 1 is traveling and the outside temperature along the route is high or low, the user is highly likely to turn on the air conditioning.

[0064] The operation history of the air conditioning by the user is stored in, for example, the memory of the ECU. The operation history of the air conditioning includes, for example, at least one of the environmental information inside the vehicle cabin and the environmental information outside the vehicle cabin when the user turns on the air conditioning. The environmental information inside the vehicle cabin is, for example, the room temperature inside the vehicle cabin. The room temperature can be detected by an interior temperature sensor (not shown) provided in the vehicle cabin. The environmental information outside the vehicle cabin is, for example, the outside temperature. It is possible to determine whether the user will turn on the air conditioning based on at least one of the environment inside the vehicle cabin and the environment outside the vehicle cabin from the operation history of the air conditioning. For example, the prediction unit 51 records the room temperature and the outside temperature when the user turns on the air conditioning as the operation history. Then, when at least one of the current room temperature and the outside temperature is equal to or close to at least one of the room temperature and the outside temperature when the user turns on the air conditioning, it is determined that the user will turn on the air conditioning. The environmental information outside the vehicle cabin may include the amount of solar radiation, etc.

[0065] The switching control unit 52 controls the circuit switching valve 7 based on the determination result of the prediction unit 51. When the prediction unit 51 predicts the start of air conditioning, the circuit switching valve 7 is opened so that the second heat medium of the battery temperature adjustment circuit 6 is sent to the heating circuit 3. Specifically, the switching control unit 52 switches the circuit switching valve 7 from a closed state to an open state, and operates the pump 61 of the battery temperature adjustment circuit 6. By sending the second heat medium of the battery temperature adjustment circuit 6 to the heating circuit 3, the first heat medium of the heating circuit 3 can be preheated or precooled by the second heat medium, as described above.

[0066] For example, when the temperature of the second heat medium in the battery temperature adjustment circuit 6 is higher than the temperature of the first heat medium in the heating circuit 3, the first heat medium is heated by the second heat medium, thereby raising the temperature of the heater core 26. Since the heater core 26 is preliminarily raised before air conditioning is started, the power consumption for raising the heater core 26 to the target temperature is reduced when air conditioning is started, compared to when the heater core 26 is not preliminarily raised. In addition, the time required to raise the heater core 26 to the target temperature after air conditioning is started is shortened. The target temperature is the temperature of the first heat medium supplied to the heater core 26, which is determined according to the set temperature of the air conditioning.

[0067] Control Procedure 3 and 4, a control procedure by the controller 5 when performing preliminary temperature adjustment control before starting air conditioning will be described below. In this example, the controller 5 starts preliminary temperature adjustment control when the air conditioning is OFF and control for heating or cooling the battery 10 is not being performed. In other words, when the air conditioning is ON and control for heating or cooling the battery 10 is being performed, the controller 5 does not execute preliminary temperature adjustment control. When the air conditioning is OFF, the heating circuit 3 does not heat the first heat medium, and therefore the heater core 26 is not heated.

[0068] Control Procedure A A control procedure A shown in FIG. 3 is an example of a procedure of preliminary temperature adjustment control for preliminarily increasing the temperature of the heater core 26.

[0069] An example of an assumed scene in control procedure A will be described. The outside air temperature is 20°C. The temperature T2 of the second heat medium in the battery temperature adjustment circuit 6 is 30°C. The temperature T1 of the first heat medium in the heating circuit 3 is 20°C. While the electric vehicle 1 is traveling, the second heat medium is warmed by heat generated by the battery 10, so the temperature T2 of the second heat medium is higher than the outside air temperature. The first heat medium is not heated in the heating circuit 3, so the temperature T1 of the first heat medium is equal to the outside air temperature. The temperature T2 of the second heat medium is substantially equal to the temperature of the battery 10. The temperature T1 of the first heat medium is substantially equal to the temperature of the heater core 26.

[0070] <Step S1> In step S1, it is determined whether or not the temperature T2 of the second heat medium is higher than the temperature T1 of the first heat medium. The temperature T2 of the second heat medium is acquired by the temperature sensor 65. The temperature T1 of the first heat medium is acquired by the first temperature sensor 35a. The temperature T2 of the first heat medium may be acquired by the second temperature sensor 35b. If the temperature T2 is higher than the temperature T1, the process proceeds to step S2. If the temperature T2 is equal to or lower than the temperature T1, the preliminary temperature adjustment control is terminated.

[0071] <Step S2> In step S2, it is determined whether the prediction unit 51 has predicted the start of air conditioning. In control procedure A, for example, it predicts whether the user will request heating from the air conditioning operation history. If the start of air conditioning is predicted, the process proceeds to step S3. If the start of air conditioning is not predicted, the preliminary temperature adjustment control ends. Steps S1 and S2 may be interchanged.

[0072] <Step S3-Step S4> In step S3, the circuit switching valve 7 is switched from a shut-off state to an open state. By opening the circuit switching valve 7, the heating circuit 3 and the battery temperature adjustment circuit 6 are connected in series. After step S3, in step S4, the pump 61 of the battery temperature adjustment circuit 6 is operated. By operating the pump 61, the second heat medium warmed by the exhaust heat of the battery 10 is sent from the battery temperature adjustment circuit 6 to the heating circuit 3. The second heat medium increases the temperature T1 of the first heat medium in the heating circuit 3, so that the heater core 26 is heated. Steps S3 and S4 may be executed simultaneously or may be interchanged.

[0073] <Step S5> Step S5 determines whether the temperature T1 of the first heat medium is saturated or the air conditioning is turned ON. Step S5 is repeated until the temperature T1 of the first heat medium is saturated. However, when the air conditioning is turned ON, the process ends. The temperature T1 of the first heat medium is saturated means that the temperature T1 of the first heat medium does not change for a certain period of time. For example, when the temperature T1 of the first heat medium does not change for 10 seconds or more, the temperature T1 of the first heat medium is deemed to be saturated. Alternatively, when the amount of change in the temperature T1 of the first heat medium per unit time is less than 1°C per minute, the temperature T1 of the first heat medium may be deemed to be saturated. When the temperature T1 of the first heat medium is saturated, the process ends. In the example of the assumed scene, the temperature T1 of the first heat medium is saturated at 25°C.

[0074] When the preliminary temperature adjustment control is completed, the circuit switching valve 7 is switched from the open state to the closed state, and the pump 61 is stopped.

[0075] The preliminary temperature adjustment control according to the control procedure A can preheat the first heat medium in the heating circuit 3 before starting air conditioning. When air conditioning is started after the preliminary temperature adjustment control is completed, the first heat medium is preheated, so the power consumption for heating the heater core 26 to the target temperature is reduced. Specifically, the power consumption of the heater 32 and the heat pump circuit 4 used to heat the first heat medium in the heating circuit 3 is reduced. In the example of the assumed scene described above, the heater core 26 can be preliminarily heated from, for example, 20°C to 25°C by the preliminary temperature adjustment control. When the air conditioning is turned from OFF to ON, for example, in the case where the heater core 26 is heated to 40°C, the first heat medium is heated from 25°C to 40°C. On the other hand, in the absence of the preliminary temperature adjustment control, the first heat medium is heated from 20°C to 40°C. Therefore, when the preliminary temperature adjustment control is performed, the power consumption for raising the first heat medium by 5°C can be reduced. In addition, the time required to heat the heater core 26 to the target temperature after the air conditioning is started is shortened.

[0076] <Control Procedure B> A control procedure B shown in FIG. 4 is an example of a procedure of preliminary temperature adjustment control for preliminarily cooling the heater core 26.

[0077] An example of an assumed scene in control procedure B will be described. The outside air temperature is 5°C. The temperature T2 of the second heat medium in the battery temperature adjustment circuit 6 is 5°C. The temperature T1 of the first heat medium in the heating circuit 3 and the temperature T3 of the evaporator 27 are 8°C. While the electric vehicle 1 is stopped, the second heat medium is cooled by the outside air, so the temperature T2 of the second heat medium is equal to the outside air temperature. The temperature T1 of the first heat medium and the temperature T3 of the evaporator 27 are slightly higher than the outside air temperature because the room temperature before the electric vehicle 1 is stopped has not been cooled to the outside air temperature. Note that control procedure B assumes a scene in which the user requests air conditioning.

[0078] <Step S11> In step S11, it is determined whether or not the temperature T2 of the second heat medium is lower than the temperature T3 of the evaporator 27. The temperature T3 of the evaporator 27 is acquired by the evaporator temperature sensor 27t. If the temperature T2 is lower than the temperature T3, the process proceeds to step S2. If the temperature T2 is equal to or higher than the temperature T3, the preliminary temperature adjustment control is terminated.

[0079] <Step S12> In step S12, it is determined whether the prediction unit 51 has predicted the start of air conditioning. In control procedure B, for example, it is predicted whether the user will request cooling from the operation history of the air conditioning. If the start of cooling is predicted, the process proceeds to step S13. If the start of cooling is not predicted, the preliminary temperature adjustment control ends. Steps S11 and S12 may be interchanged.

[0080] <Step S13-Step S14> In step S13, the circuit switching valve 7 is switched from a closed state to an open state. After step S13, in step S14, the pump 61 of the battery temperature adjustment circuit 6 is operated. The cold second heat medium is sent from the battery temperature adjustment circuit 6 to the heating circuit 3, thereby cooling the first heat medium of the heating circuit 3. That is, the heater core 26 is cooled. Steps S13 and S14 may be executed simultaneously or may be interchanged.

[0081] Step S15 is the same process as step S5 of the above-mentioned control procedure A. In the example of the assumed scene, the temperature T1 of the first heat medium is saturated at 5°C.

[0082] When the preliminary temperature adjustment control is completed, the circuit switching valve 7 is switched from the open state to the closed state, and the pump 61 is stopped.

[0083] The preliminary temperature adjustment control according to the control procedure B can pre-cool the first heat medium of the heating circuit 3 before starting the cooling operation. When the cooling operation is started after the preliminary temperature adjustment control is completed, the heater core 26 is cooled because the first heat medium has been pre-cooled. The air can be cooled by the heater core 26 even if the evaporator 27 is not sufficiently cooled. Therefore, the power consumption for cooling the evaporator 27 is reduced. Specifically, the power consumption of the heat pump circuit 4 used for cooling the third heat medium supplied to the evaporator 27 is reduced. In the example of the above assumed scene, the heater core 26 can be pre-cooled from 8°C to 5°C, for example, by the preliminary temperature adjustment control.

[0084] The present invention is not limited to these examples, but is defined by the claims, and is intended to include all modifications within the meaning and scope of the claims. [Explanation of symbols]

[0085] 1 Electric vehicles 1A Vehicle heat transfer medium circulator 10 Battery, 10t Battery Temperature Sensor 11 fan, 12 front grill, 15 outside air temperature sensor 2 Air Conditioning Unit 2i inlet, 2o outlet, 25 outlet temperature sensor 26 heater core, 27 evaporator, 27t evaporator temperature sensor 28 Air mix door, 29 Blower 3 Heating circuit 31 pump, 32 heater, 33 reserve tank 34 heat exchanger, 34a first heat exchange section, 34b second heat exchange section 35a first temperature sensor, 35b second temperature sensor 4 Heat pump circuit 4a first flow path, 4b second flow path, 4c third flow path 40 switching valve, 41 compressor, 42 condenser 44 Heating expansion valve, 45 Accumulator, 46 Cooling expansion valve, 47a first temperature sensor, 47b second temperature sensor 47c third temperature sensor, 47d fourth temperature sensor, 47e fifth temperature sensor 48 Pressure sensor, 49 Chiller expansion valve 5 Controller, 51 Prediction unit, 52 Switching control unit 6 Battery temperature adjustment circuit 61 Pump 62 chiller, 62a first heat exchange section, 62b second heat exchange section 65 Temperature sensor, 7 Circuit switching valve T1 is the temperature of the first heat transfer medium, T2 is the temperature of the second heat transfer medium T3 Evaporator temperature

Claims

[Claim 1] a heating circuit in which a first heat medium supplied to the heater core is circulated; a battery temperature adjustment circuit in which a second heat medium supplied to the battery is circulated; a circuit switching valve that switches a connection state between the heating circuit and the battery temperature adjustment circuit; a controller that controls the heating circuit, the battery temperature adjustment circuit, and the circuit switching valve, The controller includes: a prediction unit that predicts the start of air conditioning while the air conditioning is stopped; a switching control unit that controls the circuit switching valve based on a determination result of the prediction unit, the switching control unit opens the circuit switching valve so that the second heat medium of the battery temperature adjustment circuit is sent to the heating circuit when the prediction unit predicts the start of the air conditioning. Heat transfer medium circulation device for vehicles.

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