vehicle

Abstract

To effectively use heat generated in a transaxle for heating inside a cabin.SOLUTION: A vehicle is a four-wheel-drive vehicle based on front-wheel driving. A front-wheel transaxle includes a front-wheel motor, a reduction gear, and a differential gear, and transmits drive power of the front-wheel motor to front wheels. The front-wheel transaxle includes a disconnect mechanism. An air-conditioner uses heat (waste heat) that is generated in the front-wheel transaxle for heating inside a cabin. In a case where heating is requested (a positive determination at S10) and the disconnect mechanism is disconnected (a positive determination at S11) and if a first condition (a travel state with a heat dissipation to outside air from the front-wheel transaxle being equal to or higher than a given value) does not hold (a negative determination at S12), a control ECU requests connection of the disconnect mechanism. It is therefore possible to use the heat generated by co-rotation of the front-wheel transaxle for heating the inside of the cabin.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present disclosure relates to vehicles. [Background technology]

[0002] Japanese Patent Application Laid-Open Publication No. 2020-165604 (Patent Document 1) discloses a refrigerant circuit device applied to an air conditioning system for an electric vehicle. In this refrigerant circuit device, heat from a battery, inverter, etc., absorbed by a chiller arranged in a refrigerant circuit (heat pump cycle), is used to heat the vehicle interior. The heat from the battery, inverter, etc., is absorbed in the chiller by a low-temperature heat medium circuit and transported to the heater core of the air conditioning system. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2020-165604 Summary of the Invention [Problem to be solved by the invention]

[0004] Heat (waste heat) generated by the transaxle, which transmits the driving force of the drive motor (motor generator) to the wheels, is sometimes used to heat the vehicle interior. Four-wheel drive vehicles have a front-wheel transaxle for front-wheel drive and a rear-wheel transaxle for rear-wheel drive. When switching from four-wheel drive to two-wheel drive, the transaxle may be equipped with a disconnect mechanism to improve energy consumption efficiency by eliminating co-rotation of the transaxle or drive motor caused by the rotation of the driven wheels. When the disconnect mechanism is in the disconnected state, torque transmission from the driven wheels to the drive motor is cut off, suppressing co-rotation.

[0005] When the disconnect mechanism is in a disconnected state and co-rotation is suppressed, the amount of heat generated by the transaxle is reduced or eliminated, meaning that the heat generated by the transaxle cannot be effectively used to heat the passenger compartment.

[0006] An object of the present disclosure is to effectively utilize the heat generated in the transaxle to heat the vehicle interior. [Means for solving the problem]

[0007] The vehicle disclosed herein includes a front-wheel transaxle that transmits the driving force of a front-wheel motor to the front wheels, a rear-wheel transaxle that transmits the driving force of a rear-wheel motor to the rear wheels, a heating device that heats the passenger compartment, a heat management device that uses heat generated in the front-wheel transaxle and the rear-wheel transaxle for heating, and a control device, wherein at least one of the front-wheel transaxle and the rear-wheel transaxle is equipped with a disconnect mechanism that connects and disconnects torque transmission, and the control device is configured to connect the disconnect mechanism and transmit torque when a heating request is made to the heating device.

[0008] With this configuration, the control device connects the disconnect mechanism when a heating request is made to the heating device. Even when the vehicle is in two-wheel drive mode, the rotation of the driven wheels causes the transaxle or drive motor to rotate, preventing a decrease in the amount of heat generated by the transaxle. This allows the heat generated by the transaxle to be effectively used to heat the passenger compartment.

[0009] Preferably, the control device may be configured to maintain the disconnected state of the disconnected mechanism when, when there is a heating request from the heating device, the disconnected state of the disconnected mechanism and torque transmission is cut off, and when it is estimated that the amount of heat dissipated into the atmosphere from the transaxle with the disconnected mechanism in the disconnected state is equal to or greater than a predetermined value.

[0010] With this configuration, if it is estimated that the amount of heat dissipated from the transaxle to the atmosphere is equal to or greater than a predetermined value, the disconnect mechanism remains disconnected. When the amount of heat dissipated from the transaxle is large, there is little hope for using the heat generated by the transaxle for heating. In such cases, keeping the disconnect mechanism disconnected can improve energy consumption efficiency.

[0011] Preferably, the heat management device is configured to be switchable between a transport state in which heat generated in a transaxle equipped with a disconnection mechanism is transported to the heating device, and a stop state in which the heat transport is stopped. When there is a heating request from the heating device and the disconnection mechanism is in a disconnected state and torque transmission is cut off, the control device may set the disconnection mechanism to a connected state, and when the lubricating oil temperature of the transaxle equipped with the disconnection mechanism in the connected state is equal to or higher than a predetermined temperature, set the heat management device to a transport state, and when the lubricating oil temperature is below a predetermined value, set the heat management device to a stopped state.

[0012] With this configuration, when the transaxle lubricating oil temperature is equal to or higher than a predetermined temperature, heat generated in the transaxle is transported to the heating device, and when the lubricating oil temperature is below the predetermined value, heat transport to the heating device is stopped. When the transaxle lubricating oil temperature is low and below the predetermined value, heat transport is stopped, so the transaxle lubricating oil temperature can be raised quickly, allowing the heat generated in the transaxle to be effectively used to heat the passenger compartment.

[0013] Preferably, the control device may be configured to, when there is a heating request from the heating device, if the disconnect mechanism is in a disconnected state and the torque transmission is cut off, to connect the disconnect mechanism and to drive the motor of the transaxle equipped with the disconnect mechanism.

[0014] With this configuration, when the disconnect mechanism is disconnected and torque transmission is cut off, if a heating request is made to the heating device, the control device connects the disconnect mechanism and drives the motor. If the vehicle is in two-wheel drive and a heating request is made to the heating device, the control device switches to four-wheel drive, allowing the heat generated by the transaxle to be effectively used to heat the passenger compartment.

[0015] Preferably, the vehicle may further include a navigation device that provides route guidance for the vehicle. The control device is configured to connect the disconnection mechanism when there is a heating request from the heating device while the disconnection mechanism is in a disconnected state and the torque transmission is cut off, and when the distance between the route guidance destination and the current position is equal to or greater than a predetermined distance.

[0016] With this configuration, when the distance between the destination and the current location is such that the amount of heat generated by the rotation of the Torn axle is sufficient, the disconnect mechanism is connected, thereby achieving both effective use of the heat generated by the transaxle and improved energy consumption efficiency. [Effects of the Invention]

[0017] According to the present disclosure, heat generated in the transaxle can be effectively used to heat the vehicle interior. [Brief explanation of the drawings]

[0018] [Figure 1] 1 is a diagram showing a schematic configuration of a vehicle according to an embodiment of the present disclosure. [Figure 2] 10A and 10B are diagrams showing the flow of heat when the air conditioner is heating. [Figure 3] 4 is a flowchart showing an example of heating control executed by the control ECU. [Figure 4] 10 is a flowchart showing an example of heating control executed by a control ECU in the second embodiment. [Figure 5]11 is a flowchart showing an example of heating control executed by a control ECU in the third embodiment. [Figure 6] 13 is a flowchart showing an example of heating control executed by a control ECU in the fourth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0019] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present disclosure will be described in detail with reference to the accompanying drawings. In the drawings, the same or corresponding parts are designated by the same reference numerals and their description will not be repeated.

[0020] [Embodiment 1] 1 is a diagram showing a schematic configuration of a vehicle V according to this embodiment. The vehicle V is a BEV (electric vehicle). The vehicle V includes a thermal management device 1, a rear-wheel transaxle 10, a front-wheel transaxle 20, an air conditioning ECU (Electronic Control Unit) 60, a drive ECU 70, a navigation device 80, and a control ECU 50.

[0021] The thermal management device 1 is configured to perform thermal management of a vehicle V using a heat medium in a thermal management circuit 100. The thermal management circuit 100 includes a first circuit 110, a second circuit 120, and a third circuit 130. The thermal management circuit 100 also includes a condenser 140, a refrigerant circuit 150, a chiller 160, a five-way valve 310, and a reservoir tank (R / T) 320. The five-way valve 310 and the reservoir tank 320 are shared by the second circuit 120 and the third circuit 130. The condenser 140, the refrigerant circuit 150, and the chiller 160 are disposed between the first circuit 110 and the second circuit 120. The second circuit 120, the third circuit 130, and a flow path 170a (described later) are hereinafter also referred to as low-temperature side circuits.

[0022] The first circuit 110 includes a first flow path through which the high-temperature heat medium flows. The first circuit 110 includes a pump 111, an electric heater 112, a three-way valve 113, a heater core 114, a reservoir tank (R / T) 115, and a high-temperature radiator 118. The three-way valve 113 switches the path of the high-temperature heat medium. The pump 111 circulates the high-temperature heat medium through the first circuit 110. The high-temperature heat medium exchanges heat with each device as it passes through. The heater core 114 is used as a heating source (heat source) for the air conditioner 2. The air conditioner 2 heats and cools the interior of the vehicle.

[0023] The five-way valve 310 switches the path (low-temperature side circuit) of the low-temperature side heat medium. The five-way valve 310 has five ports P1 to P5. The ECU 500 controls the five-way valve 310 to establish one of the first to fifth connection patterns. Hereinafter, the ports P1, P2, P3, P4, and P5 may be referred to as "P1," "P2," "P3," "P4," and "P5," respectively.

[0024] In the first connection pattern, P1 and P2 are connected, P3 and P4 are connected, and P5 is in an unconnected state. In the second connection pattern, P1 and P2 are connected, P4 and P5 are connected, and P3 is in an unconnected state. In the third connection pattern, P1 and P5 are connected, P3 and P4 are connected, and P2 is in an unconnected state. In the fourth connection pattern, P2 and P4 are connected, P1 and P3 are connected, and P5 is in an unconnected state. In the fifth connection pattern, P2 and P4 are connected, P1 and P5 are connected, and P3 is in an unconnected state.

[0025] Flow paths 120a and 120b are connected to ports P1 and P2 of the five-way valve 310, respectively. Flow path 120a is a flow path that connects port P1 and reservoir tank 320. Flow path 120b is a flow path that connects port P2 and reservoir tank 320. By connecting P1 and P2 of the five-way valve 310 (for example, first and second connection patterns), a second circuit 120 including flow paths 120a and 120b is formed.

[0026] A pump 121 and a chiller 160 are arranged in the flow path 120a. A battery 200 and an electric battery heater 220 are arranged in the flow path 120b. The pump 121 circulates the low-temperature side heat medium through the second circuit 120. The low-temperature side heat medium exchanges heat with each device as it passes through. For this reason, each device is equipped with a heat exchanger (or has the function of a heat exchanger).

[0027] Flow paths 130b and 130a are respectively connected to ports P3 and P4 of five-way valve 310. Flow paths 130b and 130a are flow paths that connect ports P3 and P4 to reservoir tank 320. By connecting P3 and P4 of five-way valve 310 (for example, first and third connection patterns), a third circuit 130 including flow paths 130a and 130b is formed.

[0028] The high-temperature heat medium may be a known heat medium for heating, and the low-temperature heat medium may be insulating oil or antifreeze. In addition, in the refrigerant circuit 150 described later, the refrigerant may be hydrofluorocarbon (HFC), ammonia, carbon dioxide, or the like.

[0029] The flow path 130a is provided with a pump 131, an SPU (Signal Processing Unit) 132, a motor PCU (Power Control Unit) 133, and oil coolers (O / C) 134 and 136. The oil cooler 134 cools the rear-wheel-side transaxle 10, and the oil cooler 136 cools the front-wheel-side transaxle 20.

[0030] The rear-wheel transaxle 10 includes a rear-wheel motor (motor generator) 11, a reduction gear (or transmission), and a differential gear, and transmits the driving force of the rear-wheel motor 11 to the rear wheels 15. The rear-wheel transaxle 10 is cooled by circulating lubricating oil between the rear-wheel transaxle 10 and an oil cooler 134 by an electric oil pump 135.

[0031] The front-wheel-side transaxle 20 includes a front-wheel motor (motor generator) 21, a reducer (or transmission), and a differential gear, and transmits the driving force of the front-wheel motor 21 to the front wheels 25. The front-wheel-side transaxle 20 is cooled by circulating lubricating oil between the front-wheel-side transaxle 20 and an oil cooler 136 by an electric oil pump 137.

[0032] The front-wheel transaxle 20 is provided with a disconnect mechanism 22. In this embodiment, the disconnect mechanism 22 is disposed in a torque transmission path between a side gear of the differential gear and the front wheels 25. When the disconnect mechanism 22 is in an engaged state (connected state), torque is transmitted between the differential gear and the front wheels 25. When the disconnect mechanism 22 is in a disengaged state (disconnected state), torque transmission is cut off. The disconnect mechanism 22 may be composed of an electromagnetic clutch, a dog clutch, or the like. In this case, in the disengaged state, torque transmission between the differential gear and the front wheels 25 is cut off. The disconnect mechanism 22 may also be composed of a one-way clutch with a locking mechanism, or the like. In this case, in the disengaged state, torque transmission from the front wheels 25 to the differential gear is cut off, but torque transmission from the differential gear to the front wheels 25 is not cut off. In the present disclosure, the disengaged state of the disconnect mechanism refers to a state in which torque transmission from at least the wheels to the motor generator is cut off.

[0033] The rear-wheel transaxle 10 and the front-wheel transaxle 20 may be so-called e-axles that integrate an inverter (motor PCU), a motor generator, a reducer (or transmission), and a differential gear.

[0034] The pump 131 circulates the low-temperature side heat medium through the third circuit 130. The low-temperature side heat medium exchanges heat with each device as it passes through. For this reason, each device is equipped with a heat exchanger (or has the function of a heat exchanger).

[0035] A flow path 170a is connected to port P5 of the five-way valve 310. The flow path 170a connects the port P5 and the reservoir tank 320. A low-temperature radiator 170 is provided in the flow path 170a. The low-temperature radiator 170 functions as a heat exchanger. The low-temperature radiator 170 exchanges heat between the low-temperature side heat medium flowing through the flow path 170a and the outside air.

[0036] A refrigerant circulates through the refrigerant circuit 150. The refrigerant circuit 150 includes a compressor 151, an electric expansion valve 152, an evaporator 153, an evaporative pressure regulator (EPR) 154, and an electric expansion valve 155. The compressor 151 compresses and discharges the refrigerant that flows out from the chiller 160. The refrigerant circuit 150 is a refrigeration cycle or a heat pump cycle.

[0037] The evaporator 153 is used as a cooling source for the air conditioner 2. The condenser 140 is connected to both the first circuit 110 and the refrigerant circuit 150 and functions as a heat exchanger. The condenser 140 exchanges heat between the high-temperature heat medium flowing through the first circuit 110 and the refrigerant circulating through the refrigerant circuit 150. The chiller 160 is connected to both the refrigerant circuit 150 and the flow path 120a and functions as a heat exchanger. The chiller 160 exchanges heat between the refrigerant circulating through the refrigerant circuit 150 and the low-temperature heat medium flowing through the second circuit 120. In this way, the condenser 140, the refrigerant circuit 150, and the chiller 160 are configured to transfer heat between the high-temperature heat medium flowing through the first circuit 110 and the low-temperature heat medium flowing through the second circuit 120.

[0038] The air conditioner 2 heats the vehicle interior using heat dissipated from the condenser 140. The air conditioner 2 corresponds to an example of a "heating device" in the present disclosure. When the air conditioner 2 is heating, the three-way valve 113 connects ports Pa and Pb, and the high-temperature-side heat medium that absorbs heat in the condenser 140 dissipates heat in the heater core 114, thereby performing heating. When the five-way valve 310 is set to, for example, the second connection pattern (connecting P1 and P2, and P4 and P5) during heating and the battery 200 is being cooled in the low-temperature-side circuit, the heat (waste heat) of the battery 200 absorbed by the low-temperature-side heat medium is absorbed by the refrigerant in the refrigerant circuit 150 in the chiller 160, and the heat of the battery 200 is absorbed by the high-temperature-side heat medium in the condenser 140, so that the heat (waste heat) of the battery 200 is used for heating. This mode in which heating and cooling of the battery 200 are performed simultaneously is referred to as a first mode.

[0039] During heating by the air conditioner 2, if the cooling request from the battery 200 disappears, the low-temperature side circuit is switched to stop cooling the battery 200. For example, if the five-way valve 310 is set to the third connection pattern (P1 and P5, P3 and P4 connected), the low-temperature side heat medium cannot exchange heat with the battery 200, and the heat (waste heat) of the battery 200 cannot be used for heating. In this case, when the temperature of the low-temperature side heat medium is lower than the outside air, the low-temperature side heat medium absorbs heat from the outside air in the low-temperature radiator 170. Furthermore, the low-temperature side heat medium absorbs heat from the motor PCU 133 and the oil coolers 134 and 136, and this heat is absorbed by the refrigerant in the refrigerant circuit 150 in the chiller 160. Therefore, the heat of the outside air, the motor PCU 133, and the oil coolers 134 and 136 is used for heating. This mode in which the battery 200 is not cooled but heated is called a second mode.

[0040] FIG. 2 is a diagram showing the heat flow during heating in the air conditioner 2. FIG. 2(A) shows the heat flow during heating in the first mode, and FIG. 2(B) shows the heat flow during heating in the second mode. In the second mode, as shown in FIG. 2(B), heat (waste heat) from the motor PCU 133 and the oil coolers 134 and 136, absorbed by the low-temperature heat medium, is absorbed by the refrigerant in the refrigerant circuit 150 in the chiller 160. This waste heat is then absorbed by the high-temperature heat medium in the condenser 140 and radiated from the heater core 114. As a result, the heat generated in the rear-wheel transaxle 10 and the front-wheel transaxle 20 is used for heating. In the first mode, as shown in FIG. 2(A), heat from the battery 200 is radiated from the heater core 114 and used for heating.

[0041] The control ECU 50 controls the thermal management device 1 (thermal management circuit 100). The control ECU 50 includes a processor 51 and a memory 52. ​​The processor 51 executes programs stored in the memory 52, thereby performing various thermal management controls in the control ECU 50.

[0042] The air conditioning ECU 60 controls the air conditioner 2. For example, when the temperature inside the vehicle cabin falls below the air conditioning temperature set value, the air conditioner 2 performs heating. Also, when the heating switch is turned on, the air conditioner 2 performs heating. When the air conditioner 2 performs heating, the air conditioning ECU 60 transmits a heating request to the control ECU 50.

[0043] The drive ECU 70 controls the distribution of driving force between the front wheels 25 and the rear wheels 15. In this embodiment, the vehicle V is a four-wheel drive vehicle based on rear-wheel drive, and in two-wheel drive mode, the driving force distribution to the front wheels is 0 (zero). The driving force distribution is determined by, for example, the vehicle speed, acceleration / deceleration (longitudinal acceleration), the drive slip ratio of the front wheels / rear wheels, the front and rear wheel loads, etc. The drive ECU 70 controls the rear wheel motor 11 and the front wheel motor 21 to achieve the determined driving force distribution.

[0044] When the drive force distribution to the front wheels 25 becomes 0 and the vehicle enters two-wheel drive mode, the drive ECU 70 controls the disconnect mechanism 22 to a disconnected state and transmits to the control ECU 50 a message that the disconnect mechanism 22 is in a disconnected state.

[0045] The navigation device 80 provides route guidance. The navigation device 80 includes a GPS (Global Positioning System), and when a destination is set, it calculates the travel distance (route distance) from the current position to the destination and provides route guidance from the current position to the destination.

[0046] The vehicle V is provided with a grille shutter 400 that blocks the intrusion of wind into the engine compartment (enclosure) and reduces the air resistance of the vehicle V. For example, the motor PCU 133 and the front-wheel transaxle 20 are arranged inside the enclosure. When the temperature inside the enclosure reaches or exceeds a threshold, the grille shutter 400 opens to actively ventilate (cool) the inside of the enclosure. When the vehicle is traveling at high speeds above a predetermined value, the grille shutter 400 may be closed. The enclosure is the space below the front hood.

[0047] When heating is performed in the second mode, if the vehicle is in two-wheel drive, the drive power distribution to the front wheels 25 becomes zero, the front wheel motor 21 stops, and the disconnect mechanism 22 is disconnected. This reduces the amount of heat generated in the front wheel transaxle 20, or even eliminates it. This reduces the amount of heat dissipated from the heater core 114, resulting in a decrease in heating performance. To prevent this decrease, there is a concern that the power consumption of the heater 112 for heating may increase.

[0048] In this embodiment, when heating is performed in the second mode in two-wheel drive, the disconnect mechanism 22 is connected so that the heat generated in the front wheel transaxle 20 is effectively used to heat the passenger compartment.

[0049] 3 is a flowchart showing an example of heating control executed by the control ECU 50. This flowchart is repeatedly processed at predetermined intervals when the power switch (ignition switch) of the vehicle V is ON. In step (hereinafter, step will be abbreviated as "S") 10, it is determined whether or not there is a heating request. If heating is being performed by the air conditioner 2 and there is a heating request, a positive determination is made and the process proceeds to S11. If there is no heating request, the current routine is terminated.

[0050] In S11, it is determined whether the disconnect mechanism 22 is in a disconnected state. If the vehicle is in two-wheel drive and the disconnect mechanism 22 is in a disconnected state, a positive determination is made and the process proceeds to S12. If the disconnect mechanism 22 is normally connected (in four-wheel drive), a negative determination is made and the current routine is terminated.

[0051] In S12, it is determined whether a first condition is met. The first condition is met when it is estimated that the vehicle is in a driving state in which the amount of heat dissipated from front-wheel-side transaxle 20 to the atmosphere is equal to or greater than a predetermined value, and there is a concern that the temperature of the lubricating oil in front-wheel-side transaxle 20 will not effectively increase even if disconnect mechanism 22 is connected. For example, the first condition may be determined to be met when A) the vehicle speed is equal to or greater than a set vehicle speed, and cooling of front-wheel-side transaxle 20 is promoted by wind generated by the vehicle, or B) the outside air temperature is equal to or less than a set temperature, and cooling is promoted by outside air, or C) grille shutter 400 is open. Note that the first condition may be determined to be met when A to C are met simultaneously, or when a combination of A to C is met.

[0052] If the first condition is met, an affirmative determination is made in S12, and the current routine is terminated. In this case, the disconnection mechanism 22 maintains the disconnected state. If the first condition is not met, a negative determination is made, and the routine proceeds to S13. In S13, a connection request for the disconnection mechanism 22 is sent from the drive ECU 70, and the current routine is terminated. When the drive ECU 70 receives the connection request from the control ECU 50, it controls the disconnection mechanism 22 to the connected state.

[0053] According to this embodiment, the control device connects the disconnect mechanism 22 when there is a heating request from the air conditioner 2. Even when the vehicle V is in two-wheel drive mode, the rotation of the front wheels 25, which are the driven wheels, causes the front-wheel transaxle 20 transformer or the front-wheel motor 21 to rotate together. This prevents the amount of heat generated by the front-wheel transaxle 20 from decreasing, allowing the heat generated by the front-wheel transaxle 20 to be effectively used to heat the vehicle interior. Furthermore, when the amount of heat dissipated from the front-wheel transaxle 20 to the atmosphere is equal to or greater than a predetermined value (when the first condition is met), the disconnect mechanism 22 is maintained in a disconnected state. As a result, when there is little hope for using the heat generated by the front-wheel transaxle 20 for heating, energy consumption efficiency can be improved by maintaining the disconnect mechanism 22 in a disconnected state. The control ECU 50, the air conditioning ECU 60, and the drive ECU 70 correspond to an example of a "control device" in this disclosure. S12 may be omitted.

[0054] [Embodiment 2] 4 is a flowchart showing an example of heating control executed by the control ECU 50 in the second embodiment. This flowchart is repeatedly processed at predetermined intervals when the power switch (ignition switch) of the vehicle V is ON. S10, S11, and S13 are the same processes as S10, S11, and S13 in the first embodiment (FIG. 3) described above, and therefore details thereof will be omitted.

[0055] If a heating request is made (a positive determination in S10) and the disconnect mechanism 22 is in a disconnected state (a positive determination in S11), a connection request for the disconnect mechanism 22 is made in S13, and the disconnect mechanism 22 is connected. In S21, it is determined whether the lubricating oil temperature FRoT of the front-wheel transaxle 20 is equal to or higher than a predetermined temperature α. If the temperature FRoT is less than the predetermined temperature α, the process proceeds to S22. In S22, the electric oil pump 137 is stopped, and the process returns to S21. When the electric oil pump 137 is stopped, the lubricating oil does not circulate, so heat exchange in the oil cooler 136 does not occur, and heat generated in the front-wheel transaxle 20 is not transported to the heater core 114. As a result, the temperature FRoT rises quickly due to heat generated by the co-rotation of the front-wheel transaxle 20 transformer or the front-wheel motor 21.

[0056] If temperature FRoT is equal to or higher than predetermined temperature α (if it becomes equal to or higher than α), an affirmative determination is made in S21 and the routine proceeds to S23. In S23, electric oil pump 137 is operated, and the current routine ends. When electric oil pump 137 is operated, lubricating oil circulates, heat exchange occurs in oil cooler 136, and heat generated in front-wheel transaxle 20 is transported to heater core 114. This allows the heat generated in front-wheel transaxle 20 to be effectively used to heat the vehicle interior.

[0057] According to the second embodiment, when the lubricating oil temperature FRoT of the front-wheel-side transaxle 20 is below the predetermined value α, the lubricating oil temperature of the front-wheel-side transaxle 20 can be raised early, so that the heat generated in the front-wheel-side transaxle 20 can be effectively used to heat the vehicle interior. Note that a bypass passage that bypasses the oil cooler 136 may be provided in the flow path 130a, and in S22, the low-temperature heat medium may be circulated through the bypass passage to prevent the heat generated in the front-wheel-side transaxle 20 from being transported to the heater core 114.

[0058] [Embodiment 3] FIG. 5 is a flowchart showing an example of heating control executed by the control ECU 50 in the third embodiment. This flowchart is the same as the second embodiment (FIG. 4) except that S41 is added after the processing of S22 and S41 is added after the processing of S23. In S41, a drive force to the front wheels 25 is requested. When a drive force to the front wheels 25 is requested, the drive ECU 70 distributes the drive force to the front wheel motor 21, and the vehicle changes from two-wheel drive to four-wheel drive. In S42, no drive force is requested to the front wheels 25. When no drive force is requested to the front wheels 25, and drive force was distributed to the front wheel motor 21, the drive ECU 70 stops distributing the drive force and switches to two-wheel drive. If the vehicle is in two-wheel drive, the two-wheel drive state is maintained.

[0059] According to this third embodiment, when the lubricating oil temperature FRoT of the front-wheel-side transaxle 20 is below a predetermined value α, the front-wheel motor 21 is driven, so that the front-wheel motor 21 can be expected to generate heat, and the lubricating oil temperature of the front-wheel-side transaxle 20 can be raised early, so that the heat generated by the front-wheel-side transaxle 20 can be effectively used to heat the vehicle interior.

[0060] In the second embodiment (FIG. 4) and the third embodiment (FIG. 5), the process of S12 (FIG. 3) may be added between the process of S11 and the process of S13.

[0061] [Embodiment 4] 6 is a flowchart showing an example of heating control executed by the control ECU 50 in the fourth embodiment. In this flowchart, S10, S11, and S13 are the same processes as S10, S11, and S13 in the first embodiment (FIG. 3), and S21, S22, and S23 are the same processes as S21, S22, and S23 in the second embodiment (FIG. 4).

[0062] In this fourth embodiment, if the temperature FRoT of the lubricating oil in the front-wheel transaxle 20 is equal to or higher than the predetermined temperature α and a positive determination is made in S21, the electric oil pump 137 is operated in S23, a connection request is made to the disconnect mechanism 22 in S13, and the current routine is terminated.

[0063] In S22, after the electric oil pump 137 is stopped, the process proceeds to S31, where it is determined whether the travel distance from the current position to the destination set in the navigation device 80 (destination distance) is equal to or greater than a predetermined distance S. The predetermined distance S is a distance at which the heat generated by the co-rotation of the front-wheel-side transaxle 20 can sufficiently raise the temperature of the lubricating oil when the disconnect mechanism 22 is connected, and is a value set based on the outside air temperature at that time, etc.

[0064] If the destination distance is less than the predetermined distance S, a negative determination is made in S31, and the routine is terminated. If the destination distance is equal to or greater than the predetermined distance S, the routine proceeds to S32, a connection request is made to the disconnect mechanism 22, and the routine proceeds to S33. Note that if a destination has not been set, a positive determination is made in S32, and the routine may proceed to S33.

[0065] In S33, it is determined whether the temperature FRoT of the lubricating oil in the front-wheel transaxle 20 is equal to or greater than a predetermined temperature α. If the temperature FRoT is less than the predetermined temperature α, S33 is repeated. If the temperature FRoT becomes equal to or greater than the predetermined temperature α, the process proceeds to S33, where the electric oil pump 137 is operated, and the current routine is terminated.

[0066] According to this fourth embodiment, when the travel distance to the destination is a distance that allows the lubricating oil to be sufficiently heated by the heat generated by the rotation of the front-wheel transaxle 20, the disconnect mechanism 22 is connected, thereby making it possible to effectively utilize the heat generated by the front-wheel transaxle 20 and improve the efficiency of energy consumption.

[0067] In the above embodiment, an example has been described in which the disconnect mechanism 22 is provided in the front-wheel transaxle 20. However, if the vehicle V is a four-wheel drive vehicle based on front-wheel drive, the disconnect mechanism may be provided in the rear-wheel transaxle 10, and in the two-wheel drive state, the drive force distribution of the rear-wheel motor 11 may be set to 0 and the disconnect mechanism may be in a disconnected state.

[0068] In addition, a disconnect mechanism may be provided in both the front-wheel transaxle 20 and the rear-wheel transaxle 10, and the vehicle may be switched between a two-wheel drive state using front-wheel drive and a two-wheel drive state using rear-wheel drive depending on the driving state of the vehicle V.

[0069] Furthermore, when greater heating performance is required from the air conditioner 2, heating may be performed by energizing the heater 112 provided in the first circuit 110. The heater 112 may not be provided.

[0070] The embodiments disclosed herein should be considered to be illustrative in all respects and not restrictive. The scope of the present disclosure is defined by the claims, not by the description of the above embodiments, and is intended to include all modifications within the meaning and scope of the claims. [Explanation of symbols]

[0071] 1 thermal management device, 2 air conditioning device, 10 rear wheel transaxle, 11 rear wheel motor, 15 rear wheels, 20 front wheel transaxle, 21 rear wheel motor, 22 disconnect mechanism, 25 front wheels, 50 control ECU, 60 air conditioning ECU, 70 drive ECU, 80 navigation device, 100 thermal management circuit, 110 first circuit, 114 heater core, 120 second circuit, 130 third circuit, 134, 136 oil cooler, 135, 137 electric oil pump, 140 condenser, 150 refrigerant circuit, 155 electric expansion valve, 160 chiller, 170 low-temperature radiator, 200 battery, 400 grille shutter, V vehicle.

Claims

1. a front-wheel transaxle that transmits the driving force of the front-wheel motor to the front wheels; a rear-wheel transaxle that transmits the driving force of the rear-wheel motor to the rear wheels; a heating device for heating the interior of the vehicle; a heat management device that utilizes heat generated in the front-wheel transaxle and heat generated in the rear-wheel transaxle for heating; A vehicle equipped with a control device, At least one of the front-wheel-side transaxle and the rear-wheel-side transaxle is provided with a disconnect mechanism that connects and disconnects torque transmission, The control device The vehicle is configured to bring the disconnect mechanism into a connected state and perform the torque transmission when there is a heating request from the heating device.

2. The control device 2. The vehicle according to claim 1, wherein when there is a heating request from the heating device, if the disconnect mechanism is in a disconnected state and the torque transmission is disconnected, and if it is estimated that the amount of heat dissipated into the atmosphere from the transaxle with the disconnect mechanism in a disconnected state is equal to or greater than a predetermined value, the disconnect mechanism is maintained in a disconnected state.

3. the thermal management device a heat transfer state in which heat generated in the transaxle having the disconnect mechanism is transferred to the heating device and a stop state in which the heat transfer is stopped, The control device When there is a heating request from the heating device, if the disconnect mechanism is in a disconnected state and the torque transmission is disconnected, the disconnect mechanism is brought into a connected state; 2. The vehicle according to claim 1, wherein when a lubricating oil temperature of the transaxle including the disconnect device in the connected state is equal to or higher than a predetermined temperature, the thermal management device is in the transport state, and when the lubricating oil temperature is lower than the predetermined value, the thermal management device is in the stopped state.

4. The control device 2. The vehicle according to claim 1, wherein, when there is a heating request from the heating device, if the disconnect mechanism is in a disconnected state and the torque transmission is disconnected, the disconnect mechanism is brought into a connected state and a motor of a transaxle equipped with the disconnect mechanism is brought into a driving state.

5. a navigation device that provides route guidance for the vehicle; The control device 2. The vehicle according to claim 1, wherein when the disconnect mechanism is in a disconnected state and the torque transmission is disconnected, if there is a heating request from the heating device, and if the distance between the destination of the route guidance and the current position is equal to or greater than a predetermined distance, the disconnect mechanism is configured to connect.

Images