JP2008271712A - Cooling system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cooling system capable of minimizing energy for supplying a cooling medium to a drive motor and of enhancing the fuel economy of a vehicle. <P>SOLUTION: The CPU of an electronic control unit for a hybrid determines whether a hybrid vehicle is travelling on an uphill road or not (step S2). When the hybrid vehicle is determined to be travelling on an uphill road and the temperature T of the motor is a temperature T1 or more (YES in step S3), the operation of an oil cooler pump is started (step S4). When the hybrid vehicle is determined not to be travelling on an uphill road and the temperature T of the motor is a temperature T2 higher than the temperature T1 or more (YES in step S9), the operation of the oil cooler pump is started (step S10). <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a cooling device that cools a drive motor mounted on a vehicle.

  In general, a drive motor mounted on a vehicle such as an automobile has a rotor (rotor) and a stator core around which a stator coil is wound, and energizes the stator coil to generate rotational force. To get. When a current flows through the stator coil during the rotation of the rotor, the stator core and the stator coil generate heat, which affects the magnetic flux penetrating the inside of the drive motor and reduces the rotational efficiency of the rotor. Therefore, it is necessary to cool the drive motor in order to maintain the rotational efficiency of the rotor.

  As a conventional cooling device, an electric oil pump for supplying a cooling medium to a drive motor when the temperature of the drive motor is equal to or higher than a predetermined temperature and the temperature of the outside air is equal to or higher than a predetermined temperature Is known (see, for example, Patent Document 1).

As another cooling device, road information is acquired from the car navigation system, it is determined whether or not the vehicle is traveling on an uphill road based on the acquired road information, and the vehicle is traveling on the uphill road. If it is determined that the discharge amount of an electric oil pump for supplying a cooling medium to the drive motor is increased (see, for example, Patent Document 2).
JP 2005-245085 A JP 2006-312353 A

  However, in the cooling device described in Patent Document 1, it is necessary to operate the electric oil pump from a relatively marginal temperature in consideration of the situation where the temperature of the drive motor is likely to rise. Will be cooled. For this reason, the energy for supplying a cooling medium to a drive motor is consumed more than needed, and there existed a problem that the fuel consumption of a vehicle worsened.

  Further, in the cooling device described in Patent Document 2, when the cooling device described in Patent Document 1 is applied, the electric oil pump is activated when the drive motor reaches a certain temperature regardless of the traveling state of the vehicle. It will be. Here, when the vehicle is traveling on an uphill road, a high torque is required, and the time to reach the limit temperature of the drive motor is shortened. Therefore, it is necessary to operate the electric oil pump from a marginal temperature. On the other hand, when the vehicle is traveling on a flat road, it is electrically driven from the same temperature as when traveling on an uphill road, although it takes longer to reach the limit temperature of the drive motor than on the uphill road. The oil pump will be activated. Therefore, there is a problem that the energy for supplying the cooling medium to the drive motor is consumed more than necessary, and the fuel efficiency of the vehicle is deteriorated.

  The present invention has been made to solve the above-described conventional problems, and can reduce the energy for supplying the cooling medium to the drive motor to the minimum necessary, thereby improving the fuel efficiency of the vehicle. An object of the present invention is to provide a cooling device that can be used.

  In order to achieve the above object, a cooling device according to the present invention is (1) a cooling device that cools a drive motor mounted on a vehicle, wherein the vehicle supplies supply means for supplying a cooling medium to the drive motor; Determining means for determining whether or not the vehicle is traveling on an uphill road, temperature detecting means for detecting the temperature of the drive motor, and determining by the determining means that the vehicle is traveling on an uphill road, and When the temperature detected by the temperature detection means reaches the first temperature, the supply means starts to supply a cooling medium to the drive motor, and the vehicle is not traveling on the uphill road by the determination means. When the temperature detected by the temperature detection means reaches a second temperature higher than the first temperature, the supply means starts supplying the cooling medium to the drive motor. Has a control means that, the configuration with.

  With this configuration, when the vehicle is traveling on an uphill road, the speed at which the temperature of the drive motor rises is large. Therefore, when the temperature of the drive motor reaches the first temperature, a cooling medium is supplied to the drive motor. When the vehicle is not traveling on the uphill road, the speed at which the temperature of the drive motor rises is small, so the temperature of the drive motor is set to a second temperature higher than the first temperature. When it reaches, supply of the cooling medium to the drive motor is started. Therefore, since the timing for starting the supply of the cooling medium to the drive motor is controlled according to the traveling state of the vehicle, the energy for supplying the cooling medium to the drive motor can be suppressed to the minimum necessary. Fuel consumption can be improved.

  The cooling device according to the present invention is the cooling device according to (1), further comprising (2) vehicle speed detection means for detecting a vehicle speed, wherein the control means causes the vehicle to travel on an uphill road by the determination means. When the vehicle speed detected by the vehicle speed detection means is equal to or higher than a predetermined vehicle speed when the temperature detected by the temperature detection means reaches the first temperature, The supply means starts the supply of the cooling medium to the drive motor.

  With this configuration, when the vehicle travels on an uphill road and the temperature of the drive motor reaches the first temperature, the cooling medium is supplied to the drive motor when the vehicle speed is equal to or higher than a predetermined vehicle speed. To start. For this reason, when the vehicle speed is lower than a predetermined vehicle speed, that is, when the temperature of the drive motor does not increase rapidly, it is possible to prevent unnecessary supply of the cooling medium to the drive motor. Can do. Therefore, the energy for supplying the cooling medium to the drive motor can be further suppressed to the minimum necessary.

  The cooling device according to the present invention is the cooling device according to (2), wherein (3) the control unit determines that the vehicle is not traveling on an uphill road by the determination unit, and When the temperature detected by the temperature detecting means reaches the second temperature, when the vehicle speed detected by the vehicle speed detecting means is equal to or higher than a predetermined vehicle speed, a cooling medium is supplied to the drive motor. The supply unit is configured to start.

  With this configuration, when the vehicle travels on an uphill road and the temperature of the drive motor reaches the first temperature, the cooling medium is supplied to the drive motor when the vehicle speed is equal to or higher than a predetermined vehicle speed. To start. For this reason, when the vehicle speed is lower than a predetermined vehicle speed, that is, when the temperature of the drive motor does not increase rapidly, it is possible to prevent unnecessary supply of the cooling medium to the drive motor. Can do. Therefore, the energy for supplying the cooling medium to the drive motor can be further suppressed to the minimum necessary.

  Moreover, the cooling device according to the present invention is the cooling device according to any one of (1) to (3), wherein (4) the first temperature is changed according to an inclination angle of the vehicle. Have.

  With this configuration, the first temperature is changed according to the inclination angle of the vehicle. For this reason, when the inclination angle of the vehicle is small, that is, when the speed at which the temperature of the drive motor rises is small, it is possible to prevent unnecessary supply of the cooling medium to the drive motor. . Therefore, the energy for supplying the cooling medium to the drive motor can be further suppressed to the minimum necessary.

  ADVANTAGE OF THE INVENTION According to this invention, the energy for supplying a cooling medium to a drive motor can be suppressed to the minimum required, and the cooling device which can improve the fuel consumption of a vehicle can be provided.

Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is a schematic configuration diagram of a hybrid vehicle equipped with a cooling device according to an embodiment of the present invention.

First, the configuration will be described.
As shown in FIG. 1, a hybrid vehicle 1 includes an engine 2 that is controlled by an engine electronic control unit (engine ECU) 3, a carrier connected to the crankshaft of the engine 2, and a front wheel axle. A planetary gear mechanism 4 having a ring gear connected to the drive shaft, a power generating motor MG1 having a rotating shaft connected to the sun gear of the planetary gear mechanism 4, a power generating motor MG2 having a rotating shaft connected to the drive shaft, Lubricating and cooling the engine circulator system 9 having a radiator 11 and a cooling water pump 12 for circulating cooling water to a cooling water circulation path 10 connected to circulate the radiator 11 and the engine 2, and motors MG1 and MG2. A cooling circulation system 13 for the motor that cools the oil as a lubricating cooling medium, and a hybrid that controls the entire vehicle. And a de electronic control unit 17. The motors MG1 and MG2 are driven with charging / discharging of the battery 8 by switching control of switching elements of inverters 6 and 7 as drive circuits thereof by a motor electronic control unit (motor ECU) 5. In the present embodiment, motor MG2 will be described as the drive motor of the present invention.

  The motor cooling circulation system 13 is disposed in front of the vehicle and cools the oil by heat exchange with the outside air. The oil cooler 15 is connected to the oil cooler 15 in parallel with the motors MG1 and MG2. An oil circulation path 14 that circulates oil to the motors MG1 and MG2, and an oil cooler pump 16 that circulates oil through the oil circulation path 14 by pumping the oil from the motors MG1 and MG2 to the oil cooler 15 side. is doing. Here, since the oil cooler pump 16 supplies cooling oil to the motor MG2, the oil cooler pump 16 constitutes supply means of the present invention.

  The hybrid electronic control unit 17 is configured as a microcomputer centering on the CPU 18. In addition to the CPU 18, a ROM 19 for storing processing programs, a RAM 20 for temporarily storing data, an input port and an output port (not shown). And have a communication port.

  A motor temperature sensor 21, a vehicle speed sensor 22, and a gyro sensor 23 are connected to the hybrid electronic control unit 17.

  The motor temperature sensor 21 is attached to the motor MG2, detects the temperature T of the motor MG2, and outputs a signal corresponding to the detected temperature T to the hybrid electronic control unit 17. That is, the motor temperature sensor 21 constitutes the temperature detection means of the present invention.

  The vehicle speed sensor 22 detects the vehicle speed V of the hybrid vehicle 1 and outputs a signal corresponding to the detected vehicle speed V to the hybrid electronic control unit 17. That is, the vehicle speed sensor 22 constitutes the vehicle speed detection means of the present invention.

  The gyro sensor 23 detects the gravitational acceleration in the horizontal and vertical directions of the hybrid vehicle 1 and outputs a signal corresponding to the detected gravitational acceleration to the hybrid electronic control unit 17. The hybrid electronic control unit 17 calculates an uphill angle θ representing a vehicle gradient based on changes in the horizontal and vertical components of the gravitational acceleration detected by the gyro sensor 23.

  The hybrid electronic control unit 17 outputs a drive signal to the oil cooler pump 16 through an output port. The hybrid electronic control unit 17 is connected to the engine ECU 3 and the motor ECU 5 via a communication port, and exchanges various control signals and data with the engine ECU 3 and the motor ECU 5.

  The CPU 18 of the hybrid electronic control unit 17 determines whether or not the hybrid vehicle 1 is traveling on an uphill road. That is, the CPU 18 constitutes a determination unit of the present invention. Here, the uphill road in the present invention refers to a road having a vehicle gradient that requires high torque. In the present embodiment, the uphill road refers to a road having an uphill angle θ of 10 ° or more.

  Further, when the CPU 18 determines that the hybrid vehicle 1 is traveling on an uphill road and the temperature T detected by the motor temperature sensor 21 reaches a predetermined temperature T1, the CPU 18 supplies cooling oil to the motor MG2. When the oil cooler pump 16 is started to supply, it is determined that the hybrid vehicle 1 is not traveling on an uphill road, and the temperature T detected by the motor temperature sensor 21 reaches a temperature T2 higher than the temperature T1. In this case, the oil cooler pump 16 is started to supply the cooling oil to the motor MG2. That is, the CPU 18 constitutes the control means of the present invention.

  Further, when the CPU 18 determines that the hybrid vehicle 1 is traveling on an uphill road and the temperature T detected by the motor temperature sensor 21 reaches the temperature T1, the vehicle speed V is equal to or higher than a predetermined vehicle speed V1. In this case, the oil cooler pump 16 is started to supply the cooling oil to the motor MG2.

  Further, when the CPU 18 determines that the hybrid vehicle 1 is not traveling on an uphill road and the temperature T detected by the motor temperature sensor 21 reaches the temperature T2, the vehicle speed V is equal to or higher than a predetermined vehicle speed V1. In this case, the oil cooler pump 16 is started to supply the cooling oil to the motor MG2.

  Here, the cooling device according to the present embodiment includes an oil cooler pump 16, a CPU 18, a motor temperature sensor 21, and a vehicle speed sensor 22.

  Next, the operation will be described.

  FIG. 2 is a flowchart showing a schematic processing procedure of a program executed by the CPU in the hybrid electronic control unit of the cooling device according to the embodiment of the present invention. A program described below is stored in the ROM 19 in advance.

  As shown in FIG. 2, first, the CPU 18 of the hybrid electronic control unit 17 determines whether or not the vehicle speed V detected by the vehicle speed sensor 22 is equal to or higher than a predetermined speed V1 (for example, 15 km / h). (Step S1). If the CPU 18 determines that the vehicle speed V is not equal to or higher than the speed V1 (NO in step S1), the process proceeds to step S5.

  On the other hand, when it is determined that the vehicle speed V is equal to or higher than the speed V1 (YES in step S1), the CPU 18 determines whether or not the hybrid vehicle 1 is traveling on an uphill road (step S2). For example, the CPU 18 determines whether or not the uphill angle θ calculated based on the gravitational acceleration detected by the gyro sensor 23 is equal to or larger than a predetermined angle θ1 (for example, 10 °). When the CPU 18 determines that the uphill angle θ is equal to or greater than the angle θ1, the CPU 18 determines that the hybrid vehicle 1 is traveling on the uphill road. When the CPU 18 determines that the uphill angle θ is not equal to or greater than the angle θ1, the hybrid vehicle 1 is determined. Is determined not to travel on the uphill road.

  If the CPU 18 determines that the hybrid vehicle 1 is not traveling on an uphill road (NO in step S2), the CPU 18 proceeds to step S9. On the other hand, when the CPU 18 determines that the hybrid vehicle 1 is traveling on an uphill road (in the case of YES at step S2), the temperature T of the motor MG2 detected by the motor temperature sensor 21 is the temperature T1 (for example, It is determined whether it is 120 ° C. or higher (step S3).

  If the CPU 18 determines that the temperature T of the motor MG2 is not equal to or higher than the temperature T1 (NO in step S3), the CPU 18 proceeds to step S8. On the other hand, if the CPU 18 determines that the temperature T of the motor MG2 is equal to or higher than the temperature T1 (YES in step S3), the CPU 18 outputs an operation command signal to the oil cooler pump 16, and the oil cooler pump 16 is turned on. It is operated (step S4), and the process is terminated. That is, the oil cooler pump 16 starts supplying cooling oil to the motor MG2.

  Further, when determining in step S1 that the vehicle speed V is not equal to or higher than the speed V1, the CPU 18 determines whether or not the hybrid vehicle 1 is traveling on an uphill road (step S5). If the CPU 18 determines that the hybrid vehicle 1 is not traveling on an uphill road (NO in step S5), the process proceeds to step S7. On the other hand, when CPU 18 determines that hybrid vehicle 1 is traveling on an uphill road (in the case of YES at step S5), temperature T of motor MG2 detected by motor temperature sensor 21 is equal to or higher than temperature T1. Whether or not (step S6).

  If the CPU 18 determines that the temperature T of the motor MG2 is not equal to or higher than the temperature T1 (NO in step S6), the CPU 18 proceeds to step S8. On the other hand, when CPU 18 determines that temperature T of motor MG2 is equal to or higher than temperature T1 (YES in step S6), the process ends.

  If the CPU 18 determines in step S5 that the hybrid vehicle 1 is not traveling on an uphill road, the temperature T2 of the motor MG2 detected by the motor temperature sensor 21 is higher than the temperature T1 (for example, 140 ° C.). It is determined whether it is above (step S7). If the CPU 18 determines that the temperature T of the motor MG2 is not equal to or higher than the temperature T2 (NO in step S7), the CPU 18 proceeds to step S8. On the other hand, when CPU 18 determines that temperature T of motor MG2 is equal to or higher than temperature T2 (YES in step S7), the process is terminated.

  Further, when the CPU 18 determines in step S3 or step S6 that the temperature T of the motor MG2 is not equal to or higher than the temperature T1, the CPU 18 determines in step S7 that the temperature T of the motor MG2 is not equal to or higher than the temperature T2, or the oil cooler pump 16 An operation stop signal is output to stop the oil cooler pump 16 (step S8), and the process ends. That is, the oil cooler pump 16 stops supplying the cooling oil to the motor MG2.

  If the CPU 18 determines in step S2 that the hybrid vehicle 1 is not traveling on an uphill road, the CPU 18 determines whether the temperature T of the motor MG2 detected by the motor temperature sensor 21 is equal to or higher than the temperature T2. (Step S9).

  If the CPU 18 determines that the temperature T of the motor MG2 is equal to or higher than the temperature T2 (YES in step S9), the CPU 18 outputs an operation command signal to the oil cooler pump 16 to operate the oil cooler pump 16. (Step S10), and the process ends.

  On the other hand, when determining that the temperature T of the motor MG2 is not equal to or higher than the temperature T2 (NO in step S9), the CPU 18 stops the oil cooler pump 16 (step S11) and ends the process.

  Next, the temperature transition of the motor MG2 according to this embodiment will be described.

  FIG. 3 is a graph showing the time change of the temperature of the motor in the conventional cooling device. FIG. 4 is a graph showing temporal changes in the motor temperature in the cooling device according to the embodiment of the present invention.

  As shown in FIGS. 3 and 4, broken lines 101a and 103a indicate changes over time in the temperature of the motor when the hybrid vehicle is traveling on an uphill road and the oil cooler pump is not operated. Solid lines 101b and 103b indicate changes over time in the temperature of the motor when the hybrid vehicle is traveling on an uphill road and the oil cooler pump is operated. Dashed lines 102a and 104a indicate changes over time in the temperature of the motor when the hybrid vehicle is traveling on a flat road and the oil cooler pump is not operated. Solid lines 102b and 104b indicate changes over time in the temperature of the motor when the hybrid vehicle is traveling on a flat road and the oil cooler pump is operated.

  In the conventional cooling device, when the motor limit temperature is 160 ° C., the temperature is 120 ° C., which is a marginal temperature for the motor limit temperature, regardless of whether the hybrid vehicle is traveling on an uphill road. The oil cooler pump is operating. As a result, when the hybrid vehicle is traveling on an uphill road, as shown by a solid line 101b, the temperature of the motor can be suppressed at a slightly lower temperature than the limit temperature of the motor. Also, when the hybrid vehicle is traveling on a flat road, as shown by the solid line 102b, the motor temperature can be suppressed at a significantly lower temperature than when the hybrid vehicle is traveling on an uphill road. become. Therefore, when the hybrid vehicle is traveling on a flat road, the motor is cooled more than necessary, so that energy for supplying cooling oil to the motor is consumed excessively, and the hybrid vehicle is consumed. The fuel economy will be worse.

  On the other hand, in the cooling device of the present embodiment, when the hybrid vehicle 1 is traveling on an uphill road, if the limit temperature of the motor MG2 is 160 ° C., the temperature is sufficient for the limit temperature of the motor MG2. The oil cooler pump 16 is operated at 120 ° C. When the hybrid vehicle 1 is traveling on a flat road, the oil cooler pump 16 is operated at 140 ° C., which is higher than 120 ° C. As a result, both when the hybrid vehicle 1 is traveling on an uphill road and when the hybrid vehicle 1 is traveling on a flat road, as shown by the solid lines 103b and 104b, a temperature slightly lower than the limit temperature of the motor MG2. Thus, the temperature of the motor MG2 is suppressed. Therefore, the temperature of the motor MG2 is not cooled more than necessary, the energy for supplying the cooling oil to the motor MG2 can be suppressed to the minimum necessary, and the fuel efficiency of the hybrid vehicle 1 can be improved. It becomes.

  As described above, when the hybrid vehicle 1 is traveling on an uphill road, the cooling device according to the present embodiment has a high speed at which the temperature of the motor MG2 rises. Therefore, the temperature T of the motor MG2 is the temperature. When the oil cooler pump 16 starts supplying cooling oil to the motor MG2 when T1 (for example, 120 ° C.) is reached, and the hybrid vehicle 1 is not traveling on the uphill road, the temperature of the motor MG2 Since the speed at which T rises is small, the oil cooler pump 16 starts supplying cooling oil to the motor MG2 when the temperature T of the motor MG2 reaches a temperature T2 (eg, 140 ° C.) higher than the temperature T1. Let Therefore, in order to control the timing to start supplying the cooling oil to the motor MG2 according to the traveling state of the hybrid vehicle 1, the energy for supplying the cooling oil to the motor MG2 can be suppressed to the minimum necessary. The fuel efficiency of the hybrid vehicle 1 can be improved.

  In the cooling device according to the present embodiment, vehicle speed V is equal to or higher than a predetermined vehicle speed V1 when hybrid vehicle 1 travels on an uphill road and temperature T of motor MG2 reaches temperature T1. Sometimes, the oil cooler pump 16 is started to supply the cooling oil to the motor MG2. For this reason, when the vehicle speed V is lower than the predetermined vehicle speed V1, that is, when the temperature T of the motor MG2 does not rise rapidly, supply of cooling oil to the motor MG2 is unnecessarily started. Can be prevented. Therefore, the energy for supplying the cooling oil to the motor MG2 can be further suppressed to the minimum necessary.

  In the cooling device according to the present embodiment, when the hybrid vehicle 1 is not traveling on the uphill road and the temperature T of the motor MG2 reaches the temperature T2, the vehicle speed V1 is determined in advance. When this is the case, the oil cooler pump 16 is started to supply the cooling oil to the motor MG2. For this reason, when the vehicle speed V is lower than the predetermined vehicle speed V1, that is, when the temperature T of the motor MG2 does not rise rapidly, supply of cooling oil to the motor MG2 is unnecessarily started. Can be prevented. Therefore, the energy for supplying the cooling oil to the motor MG2 can be further suppressed to the minimum necessary.

  Further, in the cooling device according to the present embodiment, when the condition for causing oil cooler pump 16 to start supplying cooling oil to motor MG2 is not satisfied (NO in steps S3, S6, S7, and S9). In addition, since the oil cooler pump 16 stops supplying the cooling oil to the motor MG2, it is possible to prevent unnecessary supply of the cooling oil to the motor MG2. Therefore, the energy for supplying the cooling oil to the motor MG2 can be further suppressed to the minimum necessary.

  In the cooling device according to the present embodiment, when hybrid vehicle 1 is traveling on an uphill road, when motor temperature T reaches temperature T1 (for example, 120 ° C.), the oil cooler pump However, the present invention is not limited to this, and as described below, the motor temperature T has reached a temperature corresponding to the climb angle θ calculated based on the gravitational acceleration detected by the gyro sensor 23. Sometimes, the oil cooler pump 16 may be operated.

  Thereby, the temperature at which the oil cooler pump 16 is operated is changed according to the uphill angle θ of the hybrid vehicle 1. For this reason, when the uphill angle θ of the hybrid vehicle 1 is small, that is, when the speed at which the temperature T of the motor MG2 rises is small, the supply of cooling oil to the motor MG2 is prevented from being unnecessarily started. can do. Therefore, the energy for supplying the cooling oil to the motor MG2 can be further suppressed to the minimum necessary.

  FIG. 5 is a graph showing temporal changes in the temperature of the motor in a modification of the cooling device according to the embodiment of the present invention.

  As shown in FIG. 5, the broken line 105a indicates the time change of the temperature of the motor MG2 when the climbing angle θ is equal to or larger than the angle θ2 (for example, 15 °) and the oil cooler pump 16 is not operated. A solid line 105b indicates a temporal change in the temperature of the motor MG2 when the uphill angle θ is equal to or larger than the angle θ2 and the oil cooler pump 16 is operated.

  A broken line 106a indicates a temporal change in the temperature of the motor MG2 when the climbing angle θ is equal to or greater than the angle θ1 (for example, 10 °) and less than θ2, and the oil cooler pump 16 is not operated. A solid line 106b indicates the time change of the temperature of the motor MG2 when the climbing angle θ is not less than the angle θ1 and less than θ2, and the oil cooler pump 16 is operated. A broken line 107a indicates a time change of the temperature of the motor MG2 when the hybrid vehicle 1 is traveling on a flat road and the oil cooler pump 16 is not operated. A solid line 107b indicates a time change of the temperature of the motor MG2 when the hybrid vehicle 1 is traveling on a flat road and the oil cooler pump 16 is operated.

  In the cooling device of the present embodiment, when the climbing angle θ is equal to or larger than the angle θ2, that is, when it is a steep climbing road, if the limit temperature of the motor MG2 is 160 ° C., the limit temperature of the motor MG2 is reached. On the other hand, the oil cooler pump 16 is operated at 120 ° C., which is a roomy temperature. Further, when the climbing angle θ is not less than θ1 and less than θ2, that is, a gentle climbing road, the oil cooler pump 16 is operated at 130 ° C. higher than 120 ° C. When the hybrid vehicle 1 is traveling on a flat road, the oil cooler pump 16 is operated at 140 ° C., which is higher than 130 ° C. Here, the speed at which the temperature of motor MG2 rises increases as the climb angle θ of hybrid vehicle 1 increases. Therefore, by changing the temperature at which the oil cooler pump 16 is operated according to the uphill angle θ, the energy for operating the oil cooler pump 16 can be further reduced to the minimum necessary, and the fuel efficiency of the hybrid vehicle 1 is improved. Can be made.

  As described above, the cooling device according to the present invention has the effect that the energy for supplying the cooling medium to the drive motor can be suppressed to the minimum necessary, and the fuel efficiency of the vehicle can be improved. It is useful for a cooling device for cooling a drive motor mounted on a vehicle.

1 is a schematic configuration diagram of a hybrid vehicle equipped with a cooling device according to an embodiment of the present invention. It is a flowchart which shows the general | schematic process sequence of the program performed with CPU in the electronic control unit for hybrids of the cooling device which concerns on embodiment of this invention. It is a graph which shows the time change of the temperature of the motor in the conventional cooling device. It is a graph which shows the time change of the temperature of the motor in the cooling device which concerns on embodiment of this invention. It is a graph which shows the time change of the temperature of the motor in the modification of the cooling device which concerns on embodiment of this invention.

Explanation of symbols

1 Hybrid vehicle 16 Oil cooler pump (supply means)
17 Electronic control unit for hybrid 18 CPU (determination means, control means)
21 Motor temperature sensor (temperature detection means)
22 Vehicle speed sensor (vehicle speed detection means)
23 Gyro sensor

Claims (4)

A cooling device for cooling a drive motor mounted on a vehicle,
Supply means for supplying a cooling medium to the drive motor;
Determining means for determining whether or not the vehicle is traveling on an uphill road;
Temperature detecting means for detecting the temperature of the drive motor;
When the determination means determines that the vehicle is traveling on an uphill road and the temperature detected by the temperature detection means reaches a first temperature, a cooling medium is supplied to the drive motor. The supply means starts, the determination means determines that the vehicle is not traveling on an uphill road, and the temperature detected by the temperature detection means reaches a second temperature higher than the first temperature. And a control unit that causes the supply unit to start supplying a cooling medium to the drive motor. Vehicle speed detection means for detecting the vehicle speed,
When the determination means determines that the vehicle is traveling on an uphill road, and the temperature detected by the temperature detection means reaches the first temperature, the control speed is determined by the vehicle speed detection means. 2. The cooling device according to claim 1, wherein when the detected vehicle speed is equal to or higher than a predetermined vehicle speed, the supply unit starts to supply a cooling medium to the drive motor.   When the determination means determines that the vehicle is not traveling on an uphill road, and the temperature detected by the temperature detection means reaches the second temperature, the vehicle speed detection means 3. The cooling device according to claim 2, wherein when the detected vehicle speed is equal to or higher than a predetermined vehicle speed, the supply unit starts to supply a cooling medium to the drive motor. 4.   The cooling device according to any one of claims 1 to 3, wherein the first temperature is changed according to an inclination angle of the vehicle.