JP4337793B2 - Vehicle cooling device - Google Patents

Description

  The present invention relates to a vehicle cooling device.

  Conventionally, as a cooling device for a vehicle, for example, as disclosed in Patent Document 1, a cooling water circuit that circulates cooling water for cooling an internal combustion engine mounted on a vehicle, and an electric system (motor, inverter, An electric system cooling circuit that circulates a refrigerant for cooling a generator or the like is known.

  In the cooling device of the same document, a radiator for cooling the refrigerant is provided in the electric system cooling circuit in order to suppress an excessive increase in the temperature of the refrigerant circulating in the electric system cooling circuit and keep the refrigerant temperature below the allowable upper limit value. It has been.

  Further, the apparatus includes a heat exchanger for heating the refrigerant in the electric system cooling circuit so that the refrigerant temperature is equal to or higher than an allowable lower limit value that can make the operability and driving efficiency of the electric system suitable. And a switching valve. This heat exchanger allows cooling water in the engine cooling circuit to flow in and also flows in the refrigerant in the electric system cooling circuit to exchange heat between the two. The switching valve is for prohibiting / permitting the inflow of refrigerant from the electric system cooling circuit to the heat exchanger. When the temperature of the refrigerant in the electric system cooling circuit becomes lower than the allowable lower limit value, the switching valve is opened to allow the refrigerant to flow from the electric system cooling circuit to the heat exchanger, and the refrigerant in the heat exchanger The refrigerant is heated to a temperature equal to or higher than the allowable lower limit value through heat exchange with the cooling water.

Therefore, in the cooling device, the refrigerant in the electric system cooling circuit is cooled by a radiator or heated through heat exchange with cooling water in a heat exchanger, so that the temperature of the refrigerant is changed to the above. It can be held at a value suitable for the electric system, that is, a value within the range from the allowable lower limit value to the allowable upper limit value.
Japanese Patent Laid-Open No. 11-107749

  In the cooling device described above, the temperature of the refrigerant in the electric system cooling circuit can be maintained at a value within the range from the allowable lower limit value to the allowable upper limit value, and while appropriately cooling the electric system with the refrigerant, Their operability and driving efficiency can be maintained in a suitable state. However, it cannot be said that the temperature of the cooling water in the engine cooling circuit is adjusted to a value suitable for cooling the internal combustion engine.

  For example, when the vehicle shifts to high speed traveling or uphill traveling, the output of the internal combustion engine becomes large and the temperature of the engine tends to increase. Under these circumstances, rather than maintaining the temperature of the refrigerant in the electric system cooling circuit at a suitable value, the temperature of the cooling water in the engine cooling circuit is quickly reduced to a suitable value in the above situation. It is important to let

  However, in the cooling device, when the engine temperature is likely to become high as described above, measures are taken to quickly reduce the temperature of the cooling water in the engine cooling circuit to the preferred value. It is not done. For this reason, the cooling water temperature of the engine cooling circuit does not rapidly decrease to a value suitable for the above situation, and there is a possibility that the internal combustion engine cannot be suitably cooled by the cooling water.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide a vehicle cooling apparatus that can suitably cool not only an electric system but also an internal combustion engine. There is to do.

In the following, means for achieving the above object and its effects are described.
To achieve the above object, according to the first aspect of the present invention, an engine cooling circuit for circulating cooling water for cooling an internal combustion engine mounted on a vehicle and a refrigerant for cooling an electric system of the vehicle are circulated. The engine cooling circuit includes a radiator for cooling the cooling water circulating in the circuit, the cooling water in the engine cooling circuit and the cooling system for the vehicle. thereby enabling heat exchange means for adjusting it to vary the amount of heat exchanged in the performing and also heat exchange Niso heat exchange between the refrigerant in the electric system cooling circuit, cooling the engine A heat exchanger that allows cooling water in the circuit to flow in and flows in refrigerant in the electric system cooling circuit to exchange heat between the two, and at least one of the cooling water and the refrigerant to the heat exchanger Adjust the opening to make the inflow variable. And a flow control valve which, opening a small city of the flow control valve so that when a high cooling requirement of the internal combustion engine than the electric system is a cooling water temperature of the engine cooling circuit is decreased, the internal combustion engine when a high cooling requirement of the electrical system than is provided with a control means to a large opening degree of the flow rate adjusting valve so that the refrigerant temperature of the electric system cooling circuit is decreased.

  The invention according to claim 2 is the invention according to claim 1, wherein the vehicle is a hybrid vehicle in which an internal combustion engine and a motor are mounted as a prime mover for traveling, and the electric system cooling circuit is mounted in the vehicle. At least one of the inverter, the generator, and the motor is cooled.

According to the first and second aspects of the invention, when the necessity for cooling the internal combustion engine is higher than that of the electric system, such as when the output of the internal combustion engine becomes large, the heat exchange adjusting means by the control means The cooling water temperature of the engine cooling circuit is lowered through the control of the (flow rate adjusting valve) , and the internal combustion engine is suitably cooled by the cooling water of the engine cooling circuit. Also, when the necessity of cooling the electric system is higher than that of the internal combustion engine, such as when the output of the internal combustion engine is small and the drive rate of the electric system is high, the heat exchange adjusting means (flow rate adjusting valve) by the control means Through the control, the refrigerant temperature of the electric system cooling circuit is lowered, and the electric system is suitably cooled by the refrigerant of the electric system cooling circuit. More specifically, the refrigerant that circulates in the electric system cooling circuit becomes larger at the heat exchanger as the opening of the flow control valve is increased and the amount of at least one of the cooling water and the refrigerant flowing into the heat exchanger is increased. The heat exchange with the cooling water allows more effective cooling. In addition, the amount of heat received by the cooling water from the refrigerant in the heat exchanger decreases as the opening of the flow regulating valve is reduced and the amount of at least one of the cooling water and the refrigerant flowing into the heat exchanger is reduced. The cooling water circulating through the cooling circuit for cooling is cooled more effectively by the radiator. Therefore, the refrigerant temperature of the electric system cooling circuit decreases as the opening degree of the flow rate adjusting valve increases, and conversely, the cooling water of the engine cooling circuit decreases as the opening degree of the flow rate adjusting valve decreases. The temperature decreases. As described above, both the cooling of the internal combustion engine and the cooling of the electric system can be suitably performed both in the case where the cooling need for the internal combustion engine is high and the situation where the cooling need for the electric system is high. . In addition, when a situation change occurs between a situation in which the electrical system is highly required to be cooled and a situation in which the internal combustion engine is highly required to be cooled, the target for which the cooling need increases after the situation change is determined between the internal combustion engine and electrical system. In any case, the temperature of the cooling water or the refrigerant used for cooling the target can be quickly reduced to a suitable value through the control of the heat exchange adjusting means described above, and the target can be suitably cooled. It becomes like this.

According to a third aspect of the present invention, in the second aspect of the present invention, the electric system cooling circuit cools at least the motor, and the control means drives the internal combustion engine more preferentially than the motor. When the engine is operated, the opening of the flow rate adjustment valve is made small so that the cooling water temperature of the engine cooling circuit decreases, and when the motor is driven more preferentially than the internal combustion engine, the refrigerant temperature of the electric system cooling circuit The gist is that the opening degree of the flow rate adjusting valve is increased so that the flow rate decreases.

According to the above configuration, the electric system cooling circuit is controlled through the control of the heat exchange adjusting means (flow rate adjusting valve) by the control means under the situation where the motor is driven more preferentially than the internal combustion engine and the temperature of the motor tends to be high. The refrigerant temperature is lowered, and the motor is suitably cooled by the refrigerant in the electric system cooling circuit. Further, under the situation where the internal combustion engine is driven more preferentially than the motor and the temperature of the internal combustion engine tends to be high, the cooling water of the engine cooling circuit is controlled through the control of the heat exchange adjusting means (flow rate adjusting valve) by the control means. The temperature is lowered, and the internal combustion engine is suitably cooled by the cooling water in the engine cooling circuit. More specifically, when the internal combustion engine is driven more preferentially than the motor and the temperature of the internal combustion engine tends to rise, the opening of the flow rate adjustment valve is made small, so that the cooling water in the engine cooling circuit is effective by the radiator. The internal combustion engine can be suitably cooled by the cooling water. On the other hand, when the motor is driven more heavily than the internal combustion engine and the temperature of the motor tends to rise, the opening of the flow control valve is increased, so that the refrigerant circulating in the electric system cooling circuit is It is effectively cooled by heat exchange with the cooling water, and the motor can be suitably cooled by the refrigerant. As described above, when the driving force for running the vehicle is divided and generated by the internal combustion engine and the motor, the motor cooling and the internal combustion can be performed regardless of which of the internal combustion engine and the motor is driven with priority. Both cooling of the engine can be suitably performed. In addition, when the object to be driven intensively is switched between the internal combustion engine and the motor, the target to be driven intensively after the switching is either the internal combustion engine or the motor for cooling the object. The temperature of the cooling water or refrigerant to be used can be quickly reduced to a suitable value through the control of the heat exchange adjusting means (flow rate adjusting valve) described above, and the target can be suitably cooled.

In the invention of claim 4, wherein, in the invention of claim 3 Symbol placement, the control means, based on that it is high speed, the internal combustion engine is determined that a situation that is intensively driven than the motor It was supposed to be.

  In a hybrid vehicle in which the driving force for running the vehicle is shared between the internal combustion engine and the motor, the vehicle is mainly driven by the motor at low vehicle speeds where it is difficult to increase the driving efficiency of the internal combustion engine. A driving force is generated, and a driving force for driving the vehicle is generated mainly by the internal combustion engine at a high vehicle speed at which the driving efficiency of the internal combustion engine can be increased. According to the above configuration, the heat exchange adjusting means (flow rate adjusting valve) is controlled so that the cooling water temperature of the engine cooling circuit is lowered when the vehicle shifts to high speed running. When the engine reaches a high temperature due to the start of the intensive driving of the engine, the cooling water temperature of the engine cooling circuit can be quickly reduced to cool the internal combustion engine with high responsiveness.

According to a fifth aspect of the invention, in the fourth aspect of the invention, the control means obtains road information about a road on which the vehicle is scheduled to travel, and a high vehicle speed of the vehicle is predicted based on the obtained road information. At this time, it is determined that the internal combustion engine is driven more preferentially than the motor.

  If the heat exchange adjusting means (flow rate adjusting valve) is controlled so that the cooling water temperature of the engine cooling circuit is lowered after the vehicle has actually reached a high vehicle speed, the cooling water temperature may be delayed. It cannot be denied that if there is a delay, suitable cooling of the internal combustion engine by the cooling water is prevented. However, according to the above configuration, when it is predicted that the vehicle speed will be high, it is determined that the internal combustion engine is driven more preferentially than the motor, and heat exchange is performed so that the cooling water temperature of the engine cooling circuit decreases. The adjusting means (flow rate adjusting valve) is controlled. As a result, the above-described delay occurs in the control, and it is possible to prevent the cooling of the internal combustion engine by the cooling water from being hindered by the delay.

Focus in the invention of claim 6, wherein, in the invention of claim 3 Symbol placement, the control means, based on it is a low vehicle speed and required output of the motor is large, the motor than the internal combustion engine It was determined that the situation was driven.

  In a hybrid vehicle in which the driving force for running the vehicle is shared between the internal combustion engine and the motor, the vehicle is mainly driven by the motor at low vehicle speeds where it is difficult to increase the driving efficiency of the internal combustion engine. A driving force is generated, and a driving force for driving the vehicle is generated mainly by the internal combustion engine at a high vehicle speed at which the driving efficiency of the internal combustion engine can be increased. Therefore, when the vehicle is traveling at a low speed, such as traveling on an uphill road, and the output demand for the prime mover is large, the motor is driven more preferentially than the internal combustion engine, and the output of the motor increases. It will be a situation where the temperature of the is likely to become high. According to the above configuration, the heat exchange adjusting means (flow rate adjusting valve) is controlled so that the refrigerant temperature of the electric system cooling circuit is lowered when the vehicle shifts to the uphill traveling where the output speed to the prime mover is large at a low vehicle speed. Therefore, when the motor becomes hot due to the start of intensive driving of the motor due to traveling on the uphill road of the vehicle, etc., the temperature of the refrigerant in the electric system cooling circuit is quickly reduced, and the motor has high responsiveness. Can be cooled.

According to a seventh aspect of the invention, in the sixth aspect of the invention, the control means acquires road information about a road on which the vehicle is scheduled to travel, and based on the acquired road information, the vehicle is predicted to travel on an uphill road. In this case, it is determined that the motor is in a low vehicle speed state and the output request to the prime mover is large and the motor is driven more preferentially than the internal combustion engine.

  After the vehicle actually starts traveling on the uphill road and enters a high output request state at a low vehicle speed, the heat exchange adjusting means (flow rate adjusting valve) is controlled so that the refrigerant temperature of the electric system cooling circuit is lowered. It cannot be denied that there is a possibility of a delay in the decrease in the refrigerant temperature, and if this delay occurs, the suitable cooling of the motor by the refrigerant will be hindered. However, according to the above configuration, when traveling on an uphill road is predicted, it is determined that the output request to the prime mover is large at a low vehicle speed, and the motor is driven more preferentially than the internal combustion engine. Then, the heat exchange adjusting means (flow rate adjusting valve) is controlled so that the refrigerant temperature of the electric system cooling circuit is lowered. For this reason, the delay as described above is caused in the control, and it is possible to suppress the hindering of the preferable cooling of the motor by the refrigerant by the delay.

In the invention of claim 8, wherein, in the invention of claim 3 Symbol mounting, said hybrid vehicle further includes a battery for supplying power to the motor, focus the internal combustion engine than the motor when the battery is low When the remaining battery level is high, the motor is driven more preferentially than the internal combustion engine, and the control means emphasizes the internal combustion engine over the motor based on the low battery level. Therefore, it is determined that the motor is driven more preferentially than the internal combustion engine based on the fact that the remaining battery level is high.

  According to the above configuration, when the remaining battery level is low, the internal combustion engine is driven more preferentially than the motor to save battery power, and when the remaining battery level is high, the motor is driven more preferentially than the internal combustion engine. The fuel efficiency of the internal combustion engine is improved. And when the battery level is low, the heat exchange adjusting means (flow rate adjusting valve) is controlled so that the cooling water temperature of the engine cooling circuit is lowered. When the temperature of the engine becomes high due to the start, the temperature of the cooling water in the engine cooling circuit can be quickly reduced to cool the internal combustion engine with good responsiveness. In addition, when the battery level is high, the heat exchange adjustment means (flow rate adjustment valve) is controlled so that the refrigerant temperature of the electric system cooling circuit is lowered. When the temperature of the motor becomes high due to the above, the temperature of the refrigerant in the electric cooling circuit can be quickly reduced to cool the motor with high responsiveness.

  Hereinafter, an embodiment in which the present invention is applied to a hybrid vehicle in which a driving force for traveling is shared and generated by an internal combustion engine and a motor mounted as a prime mover will be described with reference to FIGS. 1 and 2.

  The hybrid vehicle is provided with a cooling device for cooling the internal combustion engine 1 and the motor 2 as shown in FIG. The cooling device includes an engine cooling circuit 3 that circulates cooling water to cool the internal combustion engine 1, a motor 2, an electric generator (not shown), and an electric system of an automobile such as a generator 17. And an electric system cooling circuit 4 for circulating oil (refrigerant) to cool 17. In addition, since the upper limit temperature for normal operation is relatively low and the cooling requirement is high for the inverter in the electric system of the automobile, in this embodiment, the cooling circuit for engine 3 and the cooling system for electric system 4 are different from each other. Cooling is intensively performed using a circuit. The cooling device is also provided with a heat exchanger 5 that introduces cooling water of the engine cooling circuit 3 and oil of the electric system cooling circuit 4 to exchange heat between them.

  The engine cooling circuit 3 is provided with a water pump 6 for circulating the cooling water in the circuit 3 and a radiator 7 for cooling the cooling water. The cooling of the internal combustion engine 1 is performed by passing the cooling water after being cooled by the radiator 7 through the internal combustion engine 1 when the cooling water circulates through the engine cooling circuit 3. The cooling water circulating in the engine cooling circuit 3 flows out of the radiator 7, passes through the heat exchanger 5, and then passes through the internal combustion engine 1.

  The electric system cooling circuit 4 is provided with an oil pump 8 that circulates oil in the circuit 4. The motor 2 and the generator 17 are cooled by the oil circulating in the electric system cooling circuit 4 passing through the motor 2 and the generator 17. The oil circulating in the electric system cooling circuit 4 is cooled by introducing the oil into the heat exchanger 5 and exchanging heat with the cooling water from the engine cooling circuit 3. .

Here, the structure which introduce | transduces the oil in the electric system cooling circuit 4 into the heat exchanger 5 is demonstrated.
Connected to the electric system cooling circuit 4 is a bypass passage 9 for introducing the oil in the circuit 4 into the heat exchanger 5 and returning the oil that has passed through the heat exchanger 5 to the electric system cooling circuit 4 after the introduction. ing. Therefore, a part of the oil circulating in the electric system cooling circuit 4 flows into the heat exchanger 5 through the bypass passage 9 and flows from the engine cooling circuit 3 when passing through the heat exchanger 5. Heat exchange takes place with water. Since the cooling water passing through the heat exchanger 5 is just after being cooled by the radiator 7 and has a low temperature, the heat exchange between the cooling water and the oil in the heat exchanger 5 removes heat from the oil, It will be cooled. At this time, since the heat of the oil is transmitted to the cooling water, the temperature of the cooling water also increases. Thus, the oil cooled by the cooling water in the heat exchanger 5 is returned to the electric system cooling circuit 4 through the bypass passage 9.

  Therefore, as the flow rate of the oil passing through the bypass passage 9, in other words, the flow rate of the oil flowing into the heat exchanger 5 increases, the oil circulating in the electric system cooling circuit 4 is effectively cooled by the cooling water in the heat exchanger 5. As a result, the temperature of the oil in the circuit 4 decreases. A flow rate adjusting valve 10 whose opening degree is adjusted so that the amount of oil flowing into the heat exchanger 5 is variable is provided at the portion of the bypass passage 9 where oil flows from the circuit 4. When the oil flow area of the bypass passage 9 is changed by adjusting the opening of the flow rate adjusting valve 10, the amount of oil flowing from the electric system cooling circuit 4 to the heat exchanger 5 is changed and circulates in the circuit 4. The oil temperature is adjusted.

Next, the electrical configuration of the hybrid vehicle cooling device will be described.
The cooling device includes an electronic control unit 11 that controls driving of various devices mounted on the automobile. The electronic control unit 11 includes a CPU that executes arithmetic processing related to the various controls, a ROM that stores programs and data necessary for the control, a RAM that temporarily stores arithmetic results of the CPU, and an external interface. The input / output port for inputting / outputting the signal is provided.

  The input port of the electronic control unit 11 includes an accelerator position sensor 13 for detecting the depression amount (accelerator depression amount) of the accelerator pedal 12 that is depressed by the vehicle driver, a vehicle speed sensor 14 for detecting the vehicle speed, and A navigation system 15 that identifies the current position of the vehicle and displays it on a map is connected. The navigation system 15 stores a map including various types of road information such as an expressway and an uphill road, identifies the current position of the car against the map, and roads for roads to be driven from now on. Information is output to the electronic control unit 11.

Connected to the output port of the electronic control unit 11 are drive circuits for various devices used for the operation of the internal combustion engine 1, a drive circuit for the motor 2, a drive circuit for the flow rate adjusting valve 10, and the like.
The electronic control unit 11 determines the driving force of the vehicle by the internal combustion engine 1 and the driving force of the vehicle by the motor 2 based on the traveling state of the vehicle that is grasped based on the accelerator depression amount and the vehicle speed, and the driving force is obtained. The outputs of the internal combustion engine 1 and the motor 2 are controlled.

  With such output control, a driving force for driving the vehicle is generated mainly by the internal combustion engine 1 at a high vehicle speed, and a driving force for driving the vehicle is generated mainly by the motor 2 at a low vehicle speed. This is because it is possible to increase the driving efficiency of the internal combustion engine 1 at high vehicle speeds, and it is difficult to increase the driving efficiency of the internal combustion engine 1 at low vehicle speeds. Therefore, for example, in a high-speed cruise traveling of an automobile capable of increasing the driving efficiency of the internal combustion engine 1, the internal combustion engine 1 is driven more preferentially than the motor 2, and the drive for driving the automobile mainly by the internal combustion engine 1 is performed. Force is generated. In addition, when driving at a low vehicle speed, such as traveling on an uphill road, where it is difficult to increase the driving efficiency of the internal combustion engine 1, the motor 2 is driven more preferentially than the internal combustion engine 1, and the motor 2 mainly drives the vehicle. A driving force for running is generated.

  However, in cases other than the above-described high-speed cruise traveling and uphill traveling, the share of the driving force for traveling the automobile of the internal combustion engine 1 and the motor 2 is not limited to the running state of the automobile, but the power to the motor 2 It is made to change also with the battery remaining amount of the battery 16 to supply.

  Specifically, when it is determined that the remaining battery level is low, for example, when the remaining battery level is less than a predetermined value a, the internal combustion engine 1 is driven more preferentially than the motor 2 in order to save battery power. The driving force for driving the automobile is generated mainly by the internal combustion engine 1. Further, when it is determined that the remaining amount of the battery is large, for example, when the remaining amount of the battery is equal to or greater than a predetermined value b greater than the predetermined value a, the motor 2 is more than the internal combustion engine 1 in order to improve the fuel consumption of the internal combustion engine 1. Are also driven intensively, and a driving force for driving the automobile is generated mainly by the motor 2.

  The battery remaining amount represents the amount of electricity stored in the battery 16 and decreases according to the power consumed and the time consumed when driving an electric device such as the motor 2 mounted on the automobile. Calculated as a value. Further, the battery remaining amount is calculated as a value that increases in accordance with the electric power stored and the charging time when the battery 16 is charged through power generation by the generator 17 driven by the internal combustion engine 1.

  Next, an execution procedure of the drive control of the flow rate adjusting valve 10 by the electronic control device 11 will be described with reference to a flowchart of FIG. 2 showing a heat exchange amount control routine. This heat exchange amount control routine is executed through the electronic control unit 11 by, for example, a time interruption every predetermined time.

  When adjusting the opening degree of the valve 10 through the drive control of the flow rate adjusting valve 10, the larger the opening degree of the valve 10, the more oil flows from the electric system cooling circuit 4 to the heat exchanger 5. The oil that circulates in the electric system cooling circuit 4 is more effectively cooled by heat exchange with the cooling water from the engine cooling circuit 3 in the heat exchanger 5. Further, the smaller the opening degree of the flow rate adjusting valve 10, the smaller the amount of oil flowing from the electric system cooling circuit 4 to the heat exchanger 5, and the amount of heat that the cooling water receives from the oil in the heat exchanger 5. Therefore, the cooling water circulating through the engine cooling circuit 3 is more effectively cooled by the radiator 7. Accordingly, the oil temperature of the electric system cooling circuit 4 decreases as the opening degree of the flow rate adjusting valve 10 increases, and conversely, the engine cooling circuit decreases as the opening degree of the flow rate adjusting valve 10 decreases. The oil temperature of No. 3 decreases.

  In this routine, when the internal combustion engine 1 is driven more preferentially than the motor 2, in other words, when the necessity for cooling the internal combustion engine 1 is higher than that of the electric system (motor 2), the cooling water of the engine cooling circuit 3 is used. The opening degree of the flow rate adjustment valve 10 is adjusted so that the temperature decreases. Further, when the motor 2 is driven more preferentially than the internal combustion engine 1, in other words, when the necessity for cooling the electric system (motor 2) is higher than that of the internal combustion engine 1, the refrigerant temperature of the electric system cooling circuit 4 decreases. Thus, the opening degree of the flow rate adjusting valve 10 is adjusted.

  Therefore, under the situation where the internal combustion engine 1 is driven more preferentially than the motor 2 and the temperature of the internal combustion engine 1 tends to be high, the coolant temperature of the engine cooling circuit 3 is adjusted through the opening adjustment of the flow rate adjusting valve 10. The internal combustion engine 1 is suitably cooled by the cooling water of the engine cooling circuit 3. Further, under the situation where the motor 2 is driven more preferentially than the internal combustion engine 1 and the temperature of the motor 2 is likely to increase, the oil temperature of the electric system cooling circuit 4 decreases through the adjustment of the opening degree of the flow rate adjusting valve 10. The motor 2 is suitably cooled by the oil of the electric system cooling circuit 4.

  As described above, both of the cooling of the internal combustion engine 1 and the cooling of the motor 2 can be suitably performed regardless of which of the internal combustion engine 1 and the motor 2 is driven with priority. Further, when the object to be driven intensively is switched between the internal combustion engine 1 and the motor 2, whether the object to be driven intensively after the switching is the internal combustion engine 1 or the motor 2, The temperature of the cooling water or oil used for cooling the target can be quickly reduced to a value suitable for cooling through the adjustment of the opening degree of the flow rate adjusting valve 10 described above. For this reason, it is possible to effectively cool the object that is driven intensively after the switching.

  As a specific process for adjusting the opening degree of the flow rate adjusting valve 10, first, as a determination as to whether or not the internal combustion engine 1 is driven more preferentially than the motor 2, the automobile is traveling at high speed cruise. It is determined whether or not (S101). Such a determination is made based on, for example, whether or not the vehicle speed obtained based on the detection signal from the vehicle speed sensor 14 maintains a high value. When an affirmative determination is made in step S101, it is determined that the internal combustion engine 1 is in a situation where it is driven more preferentially than the motor 2. Thus, when the internal combustion engine 1 is intensively driven and the temperature of the internal combustion engine 1 tends to increase, the opening of the flow rate adjustment valve 10 is made smaller than the normal value in order to preferentially cool the internal combustion engine 1 ( S102).

  Note that the normal value here is, for example, cooling that circulates through the engine cooling circuit 3 while suitably cooling the motor 2 with oil that circulates through the electric system cooling circuit 4 under the standard driving state of an automobile. It is a value determined in advance by experiments or the like as a value that can suitably cool the internal combustion engine 1 with water.

  When the opening degree of the flow rate adjustment valve 10 is made smaller than the normal value by the process of step S102, the heat amount received by the cooling water from the oil in the heat exchanger 5 is made small, and the engine receives the heat amount received from the oil. The temperature rise of the cooling water circulating through the cooling circuit 3 is suppressed. Therefore, when the internal combustion engine 1 is driven intensively due to the high-speed cruise traveling and the temperature of the internal combustion engine 1 tends to increase, the cooling water in the engine cooling circuit 3 is effectively cooled by the radiator 7. Thus, the internal combustion engine 1 can be suitably cooled by the cooling water.

  On the other hand, when a negative determination is made in step S101, it is determined whether or not the automobile is traveling on an uphill road as a determination as to whether or not the motor 2 is driven more preferentially than the internal combustion engine 1. (S103). Such a determination is made based on, for example, whether the vehicle speed required based on the detection signal from the vehicle speed sensor 14 is low and whether the output request for the motor of the automobile is large. The magnitude of the output request for the prime mover here is, for example, the magnitude of the output command value, which is a command value when driving the motor 2, or the accelerator depression amount obtained based on the detection signal from the accelerator position sensor 13. It is possible to use.

  In traveling on an uphill road, it is difficult to increase the driving efficiency of the internal combustion engine 1 due to the low speed of the vehicle, so the motor 2 is driven more preferentially than the internal combustion engine 1 to generate a driving force for driving the vehicle. Moreover, since the output of the motor 2 is increased, the temperature of the motor 2 is likely to increase. Therefore, when an affirmative determination is made in step S103, it is determined that the motor 2 is driven more preferentially than the internal combustion engine 1 and that the temperature of the motor 2 is likely to increase. At this time, the opening degree of the flow rate adjustment valve 10 is set to be larger than the normal value in order to preferentially cool the motor 2 (S104).

  When the opening degree of the flow rate adjusting valve 10 is made larger than the normal value by the process of step S104, the oil circulating in the electric system cooling circuit 4 is cooled by the heat exchanger 5 from the engine cooling circuit 3 side. It is effectively cooled by heat exchange with water. Therefore, when the motor 2 is driven intensively due to the traveling on the uphill road and the temperature of the motor 2 tends to increase, the motor 2 can be suitably cooled by the oil in the electric system cooling circuit 4. become.

  By the way, when it is other than the high-speed cruise traveling and the uphill traveling described above (both NO in S101 and S102), the share of the driving force for traveling the vehicle of the internal combustion engine 1 and the motor 2 is only in the traveling state of the vehicle. As described above, it is not limited to change depending on the remaining battery level. That is, the internal combustion engine 1 is driven more preferentially than the motor 2 in order to save battery power when the remaining battery level is low, and the motor 2 is driven in order to improve the fuel consumption of the internal combustion engine 1 when the remaining battery level is high. Drive more focused than. In consideration of this, in the processing of steps S105 to S108, it is preferable to adjust the opening of the flow rate adjustment valve 10 according to the remaining battery level and to drive the engine 1 or the motor 2 with priority. I'm trying to cool it down.

  As a specific process for adjusting the opening degree of the flow rate adjusting valve 10, first, it is determined whether or not the internal combustion engine 1 is being driven more preferentially than the motor 2. Is determined (S105). Such a determination is made based on, for example, whether the remaining battery level is less than the predetermined value a described above. When an affirmative determination is made in step S105, it is determined that the internal combustion engine 1 is in a situation where it is driven more preferentially than the motor 2. Thus, when the internal combustion engine 1 is intensively driven and the temperature of the internal combustion engine 1 tends to increase, the opening of the flow rate adjustment valve 10 is made smaller than the normal value in order to preferentially cool the internal combustion engine 1 ( S106). As a result, the temperature of the cooling water circulating through the engine cooling circuit 3 is suppressed from rising due to heat exchange with oil from the electric system cooling circuit 4 side in the heat exchanger 5. The cooling water can be effectively cooled by the radiator 7 and the internal combustion engine 1 can be suitably cooled by the cooling water.

  On the other hand, when a negative determination is made in step S105, it is determined whether or not the remaining amount of the battery is large as a determination of whether or not the motor 2 is being driven more preferentially than the internal combustion engine 1 ( S107). Such a determination is made based on, for example, whether the remaining battery level is equal to or greater than the predetermined value b described above. When an affirmative determination is made in step S107, it is determined that the motor 2 is in a state of being driven more preferentially than the internal combustion engine 1. Thus, when the motor 2 is driven intensively and the temperature of the motor 2 tends to increase, the opening degree of the flow rate adjusting valve 10 is set larger than the normal value to preferentially cool the motor 2 (S108). As a result, the oil circulating in the electric system cooling circuit 4 is effectively cooled by heat exchange with the cooling water from the engine cooling circuit 3 side in the heat exchanger 5, so that the motor 2 is cooled by the oil. It becomes possible to perform suitably.

When a negative determination is made in the process of step S107, the opening degree of the flow rate adjustment valve 10 is set to the normal value described above (S109).
According to the embodiment described in detail above, the following effects can be obtained.

  (1) When the internal combustion engine 1 is driven more preferentially than the motor 2 and the temperature of the internal combustion engine 1 tends to be high, the opening degree of the flow rate adjustment valve 10 is made smaller than the normal value. As a result, the amount of heat that the cooling water receives from the oil in the heat exchanger 5 is reduced, and the temperature of the cooling water that circulates through the engine cooling circuit 3 is suppressed by the amount of heat received from the oil. Cooling water in the cooling circuit 3 can be effectively cooled by the radiator 7 and the internal combustion engine 1 can be suitably cooled by the cooling water. Further, when the motor 2 is driven more preferentially than the internal combustion engine 1 and the temperature of the motor 2 tends to be high, the opening degree of the flow rate adjustment valve 10 is made larger than the normal value, and the electric system cooling circuit Since the oil circulating through 4 is effectively cooled by heat exchange with the cooling water from the engine cooling circuit 3 side in the heat exchanger 5, the motor 2 can be suitably cooled by the oil. As described above, both of the cooling of the internal combustion engine 1 and the cooling of the motor 2 can be suitably performed regardless of which of the internal combustion engine 1 and the motor 2 is driven with priority. Further, when the object to be driven intensively is switched between the internal combustion engine 1 and the motor 2, whether the object to be driven intensively after the switching is the internal combustion engine 1 or the motor 2, The temperature of the cooling water or oil used for cooling the target can be quickly reduced to a value suitable for cooling through the adjustment of the opening degree of the flow rate adjusting valve 10 described above. For this reason, it is possible to effectively cool the object that is driven intensively after the switching.

  (2) In a hybrid vehicle, the internal combustion engine 1 is driven more preferentially than the motor 2 at a high vehicle speed at which the drive efficiency of the internal combustion engine 1 can be increased, and the vehicle is mainly driven by the internal combustion engine 1. The driving force is generated. Therefore, it can be determined that the internal combustion engine 1 is driven more preferentially than the motor 2 based on the fact that the automobile is traveling at high speed. And when it is judged that, the opening degree of the flow regulating valve 10 is made smaller than a normal value. As described above, when the vehicle shifts to high-speed cruise traveling, the opening degree of the flow rate adjusting valve 10 is made small, so that the internal combustion engine 1 of the internal combustion engine 1 is caused by the start of the intensive driving of the internal combustion engine 1 accompanying high-speed cruise traveling. When the temperature becomes high, the cooling water temperature of the engine cooling circuit 3 can be quickly reduced to cool the internal combustion engine 1 with high responsiveness.

  (3) In the hybrid vehicle, at a low vehicle speed at which it is difficult to increase the driving efficiency of the internal combustion engine 1, the motor 2 is driven more preferentially than the internal combustion engine 1. The driving force necessary for the generation is generated. Therefore, it can be determined that the motor 2 is driven more preferentially than the internal combustion engine 1 based on the fact that the vehicle is traveling on an uphill road where the vehicle speed is low and the output demand is high. And when it is judged that, the opening degree of the flow regulating valve 10 is made larger than a normal value. As described above, since the opening of the flow rate adjusting valve 10 is increased when the vehicle shifts to the uphill traveling, the temperature of the motor 2 is increased due to the start of the intensive driving of the motor 2 accompanying the uphill traveling. When the temperature becomes high, the oil temperature of the electric system cooling circuit 4 can be quickly reduced to cool the motor 2 with good responsiveness.

  (4) When the vehicle is not traveling at high speed cruise or traveling on an uphill road, the share of driving force for driving the vehicle between the internal combustion engine 1 and the motor 2 is not limited to the driving state of the vehicle but also changes depending on the remaining battery level. To be done. That is, when it is determined that the remaining battery level is low, the internal combustion engine 1 is driven more preferentially than the motor 2 in order to generate a driving force for running the automobile. By thus driving the internal combustion engine 1 with priority, battery power can be saved. Further, when it is determined that the battery remaining amount is large, the motor 2 is driven more preferentially than the internal combustion engine 1 in generating the driving force for running the automobile. Thus, the fuel efficiency of the internal combustion engine 1 can be improved by driving the motor 2 with priority.

  (5) When the remaining battery level is low, the internal combustion engine 1 is driven more preferentially than the motor 2 as described in (4) above. For this reason, it can be determined that the internal combustion engine 1 is driven more preferentially than the motor 2 based on the fact that the remaining battery level is low. And when it is judged that, the opening degree of the flow regulating valve 10 is made smaller than a normal value. As described above, when the remaining amount of the battery is low, the opening degree of the flow rate adjusting valve 10 is made small, so that the engine becomes hot due to the start of the intensive driving of the internal combustion engine 1 due to the low remaining amount of the battery. When this happens, the temperature of the cooling water in the engine cooling circuit 3 can be quickly reduced, and the internal combustion engine 1 can be cooled with good responsiveness.

  (6) When the remaining amount of the battery is large, the motor 2 is driven more preferentially than the internal combustion engine 1 as described in (4) above. Therefore, it can be determined that the motor 2 is driven more preferentially than the internal combustion engine 1 based on the fact that the remaining battery level is large. And when it is judged that, the opening degree of the flow regulating valve 10 is made larger than a normal value. As described above, when the remaining amount of the battery is large, the flow rate adjustment valve 10 is made large. Therefore, when the motor 2 becomes hot due to the intensive driving of the motor 2 due to the large amount of remaining battery, The oil temperature of the electric system cooling circuit 4 can be quickly reduced, and the motor 2 can be cooled with good responsiveness.

In addition, the said embodiment can also be changed as follows, for example.
When the road information about the road on which the vehicle is scheduled to travel is acquired based on the road information from the navigation system 15 and the high-speed cruise traveling of the vehicle is predicted based on the acquired road information, the internal combustion engine 1 is more than the motor 2. The degree of opening of the flow rate adjustment valve 10 may be made small so that it is determined that the situation is driven intensively and the cooling water temperature of the engine cooling circuit 3 is lowered. If the opening of the flow rate adjustment valve 10 is made small so that the cooling water temperature of the engine cooling circuit 3 is lowered after the automobile has been cruising at high speed, there is a possibility that the cooling water temperature may be delayed. Therefore, the cooling of the internal combustion engine 1 by the cooling water is hindered by the delay. However, when high-speed cruise traveling is predicted based on the acquired road information, it is determined that the internal combustion engine 1 is in a state of being driven preferentially, and the opening of the flow rate adjustment valve 10 is reduced, as described above. Further, it is possible to suppress a delay in the cooling water temperature drop of the engine cooling circuit 3 and prevent the cooling of the internal combustion engine 1 by the cooling water by the delay.

  When the road information about the road on which the vehicle is scheduled to travel is acquired based on the road information from the navigation system 15, and the uphill traveling of the vehicle is predicted based on the acquired road information, the motor 2 is more than the internal combustion engine 1. The opening degree of the flow rate adjustment valve 10 may be increased so as to determine that the situation is driven intensively and to reduce the oil temperature of the electric system cooling circuit 4. If the opening degree of the flow rate adjustment valve 10 is increased so that the oil temperature of the electric system cooling circuit 4 decreases after the automobile actually starts traveling on the uphill road and becomes a high output demand state at a low vehicle speed, There is a possibility that a delay occurs in the lowering of the oil temperature, and the cooling of the motor 2 by the oil is hindered by the delay. However, when traveling on an uphill road is predicted based on the acquired road information, if it is determined that the motor 2 is in a state of being driven intensively and the opening of the flow rate adjustment valve 10 is increased, as described above. It is possible to suppress a delay in the decrease in the oil temperature of the electric system cooling circuit 4 and prevent the motor 2 from being cooled by the oil by the delay.

When the opening degree of the flow control valve 10 is made smaller than the normal value during high-speed cruise traveling of the automobile, the opening degree is made smaller as the vehicle speed becomes larger while making the opening degree smaller than the normal value as shown in FIG. You may change so that it may become. During high-speed cruise traveling, the temperature of the internal combustion engine 1 tends to increase as the vehicle speed increases. For this reason, if the opening degree of the flow rate adjustment valve 10 is adjusted according to the vehicle speed as described above, the cooling water temperature of the engine cooling circuit 3 for cooling the internal combustion engine 1 is reduced to a value suitable for the vehicle speed, It is possible not to reduce more than necessary. Further, if the cooling water temperature of the engine cooling circuit 3 is lowered more than necessary, that is, if the opening degree of the flow rate adjusting valve 10 is made smaller than necessary, the cooling water in the heat exchanger 5 will be described. The amount of heat exchange with the oil in the electric system cooling circuit 4 decreases, and the oil temperature may become excessively high. However, this problem does not occur.
-When the opening of the flow rate adjustment valve 10 is made larger than the normal value when the vehicle is traveling on an uphill road, the output request (accelerator opening etc.) is made while making the opening larger than the normal value as shown in FIG. ) May be increased as the value increases. When traveling on an uphill road, the temperature of the motor 2 tends to increase as the output requirement increases. Therefore, if the opening of the flow rate adjustment valve 10 is adjusted according to the output request as described above, the oil temperature of the electric system cooling circuit 4 for cooling the motor 2 is reduced to a value suitable for the output request. It is possible not to reduce more than necessary. Further, if the oil temperature of the electric system cooling circuit 4 is lowered more than necessary, that is, if the opening degree of the flow control valve 10 is made larger than necessary, the oil and engine in the heat exchanger 5 There is a risk that the amount of heat exchange with the cooling water in the cooling circuit 3 will increase and the cooling water temperature will increase. However, this problem does not occur.

  As shown in FIG. 5, a bypass passage 22 is connected so that a part of the electric system cooling circuit 4 passes through the heat exchanger 5 and bypasses the heat exchanger 5 to the engine cooling circuit 3. The flow rate adjusting valve 21 may be provided downstream of the connection portion with the bypass passage 22 in the engine cooling circuit 3. In this case, under the situation where the internal combustion engine 1 is driven more preferentially than the motor 2, the opening of the flow rate adjustment valve 21 is adjusted to be smaller than the normal value. The inflow of cooling water is reduced. As a result, the cooling water circulating through the engine cooling circuit 3 is effectively cooled by the radiator 7, and the temperature of the cooling water for cooling the internal combustion engine 1 is lowered. Further, under the situation where the motor 2 is driven more preferentially than the internal combustion engine 1, the opening degree of the flow rate adjustment valve 21 is adjusted to be larger than the normal value, thereby cooling the heat exchanger 5. Water inflow is increased. As a result, the oil circulating in the electric system cooling circuit 4 is effectively cooled by the cooling water in the heat exchanger 5, and the temperature of the oil for cooling the motor 2 is lowered. The normal value is determined by the cooling water circulating through the engine cooling circuit 3 while suitably cooling the motor 2 with oil circulating through the electric cooling circuit 4 under the standard driving state of the automobile. As a value that can cool the internal combustion engine 1 suitably, a value determined in advance through experiments or the like is used. Even in this case, it is possible to obtain the same effect as that of the above embodiment.

The bypass passage 22 and the flow rate adjustment valve 21 may be provided in addition to the configuration including the bypass passage 9 and the flow rate adjustment valve 10 shown in FIG.
A radiator for cooling the oil may be provided in the electric system cooling circuit 4. In this case, the opening degree of the flow rate adjusting valve is made variable based on the temperature of the oil and the temperature of the cooling water in the engine cooling circuit 3. That is, under the situation where the internal combustion engine 1 is cooled more preferentially than the motor 2, the flow rate adjustment valve is opened so that the cooling water temperature of the engine cooling circuit 3 is lowered based on the temperature of the oil and cooling water. The degree is adjusted. Also, under the situation where the motor 2 is cooled more preferentially than the internal combustion engine 1, the opening of the flow rate adjustment valve is set so that the oil temperature of the electric system cooling circuit 4 is lowered based on the oil and cooling water temperatures. Is adjusted.

As shown in FIG. 6, not only the motor 2 and the generator 17 are cooled by the electric system cooling circuit 4, but also the inverter 18 may be cooled.
The electric system cooling circuit 4 may be dedicated to inverter cooling. In this case, when the necessity for cooling the inverter is higher than that of the internal combustion engine 1, the opening degree of the flow rate adjusting valve is adjusted so that the oil temperature of the electric system cooling circuit 4 is lowered. When the necessity for cooling the internal combustion engine 1 is higher than that of the inverter, the opening degree of the flow rate adjusting valve is adjusted so that the coolant temperature of the engine cooling circuit 3 is lowered.

  The electric cooling circuit 4 may be dedicated to cooling the generator 17. In this case, when the necessity for cooling the generator 17 is higher than that of the internal combustion engine 1, the opening degree of the flow rate adjusting valve is adjusted so that the oil temperature of the electric system cooling circuit 4 is lowered. When the necessity for cooling the internal combustion engine 1 is higher than that of the generator 17, the opening degree of the flow rate adjustment valve is adjusted so that the cooling water temperature of the engine cooling circuit 3 is lowered.

The electric cooling circuit 4 may be dedicated to cooling the motor 2.
The electric system cooling circuit 4 can be used only for cooling the motor 2 and the inverter, or can be used only for cooling the inverter and the generator 17.

-You may apply this invention to the motor vehicle provided with electric systems, such as a motor, an inverter, and a generator, and using only an internal combustion engine as a driving | running | working prime mover.
A fluid other than oil may be employed as a refrigerant that circulates in the electric system cooling circuit 4 and cools the motor 2.

1 is a schematic diagram showing a cooling system of a hybrid vehicle to which a cooling device of the present invention is applied. The flowchart which shows the execution procedure of the drive control of the flow regulating valve for adjusting the heat exchange amount in the heat exchanger of the said cooling device. The graph which shows transition of the opening degree of the flow regulating valve with respect to the change of a vehicle speed. The graph which shows transition of the opening degree of the flow regulating valve with respect to the change of an output request | requirement. Schematic which shows the other example of the cooling system in a hybrid vehicle. Schematic which shows the other example of the cooling system in a hybrid vehicle.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Internal combustion engine, 2 ... Motor, 3 ... Engine cooling circuit, 4 ... Electric system cooling circuit, 5 ... Heat exchanger, 6 ... Water pump, 7 ... Radiator, 8 ... Oil pump, 9 ... Bypass passage (Heat exchange Adjustment means), 10 ... Flow rate adjustment valve (heat exchange adjustment means), 11 ... Electronic control device (control means), 12 ... Accelerator pedal, 13 ... Accelerator position sensor, 14 ... Vehicle speed sensor, 15 ... Navigation system, 16 ... Battery , 17 ... generator, 18 ... inverter, 21 ... flow rate adjustment valve (heat exchange adjusting means), 22 ... bypass passage (heat exchange adjusting means).

Claims (8)

In a vehicle cooling apparatus, comprising: an engine cooling circuit that circulates cooling water for cooling an internal combustion engine mounted on a vehicle; and an electric system cooling circuit that circulates a refrigerant for cooling an electric system of the vehicle.
The engine cooling circuit includes a radiator for cooling the cooling water circulating in the circuit,
Possible heat to varying the amount of heat exchanged in the heat exchange between both the heat exchange Niso between the refrigerant in the electric system cooling circuit and the cooling water in the cooling circuit for the engine as a replacement adjusting means, of a heat exchanger to perform heat exchange therebetween by the inflow refrigerant of the electric system cooling circuit with flowing the cooling water of the engine cooling circuit, to the heat exchanger A flow rate adjustment valve whose opening degree is adjusted so as to make the inflow amount of at least one of the cooling water and the refrigerant variable ;
When the necessity of cooling the internal combustion engine is higher than that of the electric system, the opening of the flow rate adjusting valve is made small so that the cooling water temperature of the engine cooling circuit is lowered, and the electric system needs to be cooled more than the internal combustion engine. cooling device for a vehicle when a high sexual characterized in that it comprises a control means to a large opening degree of the flow control valve so that the refrigerant temperature of the electric system cooling circuit is decreased. The vehicle is a hybrid vehicle equipped with an internal combustion engine and a motor as a prime mover for traveling,
The vehicle cooling device according to claim 1, wherein the electric system cooling circuit cools at least one of an inverter, a generator, and the motor mounted on the vehicle. The electric system cooling circuit cools at least the motor,
When the internal combustion engine is driven more preferentially than the motor, the control means reduces the opening of the flow rate adjustment valve so that the cooling water temperature of the engine cooling circuit decreases, and the motor The vehicle cooling device according to claim 2, wherein the opening degree of the flow rate adjustment valve is increased so that the refrigerant temperature of the electric system cooling circuit is lowered when driven more preferentially.   The control means determines that the internal combustion engine is driven more preferentially than the motor based on the high vehicle speed.
  The vehicle cooling device according to claim 3.   The control means acquires road information about a road on which the vehicle is scheduled to travel, and when the high vehicle speed of the vehicle is predicted based on the acquired road information, the internal combustion engine is driven more preferentially than the motor. Judge that the situation is
  The vehicle cooling device according to claim 4.   The control means determines that the motor is driven more preferentially than the internal combustion engine based on a low vehicle speed and a large output request to the prime mover.
  The vehicle cooling device according to claim 3.   The control means acquires road information about a road on which the vehicle is scheduled to travel, and when an uphill traveling of the vehicle is predicted based on the acquired road information, an output request to the prime mover is large in a low vehicle speed state, Judging that the motor is driven more preferentially than the internal combustion engine
  The vehicle cooling device according to claim 6.   The vehicle includes a battery that supplies electric power to the motor, and the internal combustion engine is driven more preferentially than the motor when the remaining battery level is low, and the motor is higher than the internal combustion engine when the remaining battery level is high. It is driven heavily,
  The control means determines that the internal combustion engine is driven more preferentially than the motor based on a low remaining battery level, and the motor is greater than the internal combustion engine based on a large remaining battery level. Judging that the situation is focused on
  The vehicle cooling device according to claim 3.

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