JPH11313406A - Hybrid vehicle cooling system - Google Patents

Abstract

(57) [Summary] [PROBLEMS] In a hybrid vehicle, the engine can be quickly warmed up to improve the fuel efficiency of the engine, reduce harmful components in exhaust gas, and simplify the piping system to make the whole compact. To do. It is also necessary to reduce the fluctuation range of the temperature cycle applied to the electric component, and to improve the life and reliability of the component. A hybrid vehicle equipped with components such as an engine and a rotary electric machine as a drive system, and having a plurality of cooling pipes through which liquid flows to cool the components, and radiators is provided. A cooling device provided with a heat exchanger 4 for exchanging heat between the liquid and a circulating system for cooling the components and a circulating system for cooling components 2 and the like that do not include the engine 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cooling system for a hybrid vehicle having a plurality of components such as an engine and a rotating electric machine.

[0002]

2. Description of the Related Art As a cooling device for an engine, a rotating electric machine, and a power converter in a conventional hybrid vehicle, for example, as described in JP-A-5-131848,
A hybrid vehicle equipped with a plurality of components such as an engine and a rotating electric machine and having a plurality of cooling pipes through which a liquid flows so as to cool each of the components; A valve that opens a flow path between the pipe and a cooling pipe for a component that uses exhaust heat in response to a signal; and a control unit that opens the flow path. The engine is heated by heat, and after the engine warms up, each component including the engine is controlled to cool down, improving the fuel efficiency of the engine,
It is known to reduce harmful components (hereinafter referred to as emissions) in exhaust gas.

[0003]

According to such a cooling device for a hybrid vehicle, the piping is complicated because the circulating system for cooling the engine and the circulating system for cooling the rotating electric machine and the like are directly joined and branched. There was a problem. Further, since control means for opening and closing the valve is required, there is a problem that the control circuit becomes complicated. Furthermore, in order to adjust the flow required for cooling each component,
It is necessary to adjust the opening and closing accurately by coordinating a plurality of valves, and this control is very difficult. In addition, no consideration has been given to the mounting of the entire component including the cooling system.

SUMMARY OF THE INVENTION An object of the present invention is to make it possible to quickly warm up an engine in a hybrid vehicle, improve the fuel efficiency of the engine, reduce emissions, and simplify the piping system to make the whole compact. An object of the present invention is to obtain a cooling device for a hybrid vehicle.

Another object of the present invention is to provide a hybrid vehicle that can quickly warm up the engine, improve the fuel efficiency of the engine, reduce the emission, and warm up the power converter, thereby improving the electrical components. It is an object of the present invention to provide a cooling device for a hybrid vehicle, which can reduce a fluctuation range of a temperature cycle applied to a vehicle and can improve a component life and reliability.

[0006]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a hybrid having a plurality of components such as an engine and a rotating electric machine mounted thereon as a drive system, and having a plurality of cooling pipes and a radiator through which a liquid flows so as to cool the components. This is achieved by providing a vehicle with a heat exchanger that performs heat exchange between a circulation system for cooling the engine and a circulation system for cooling components not including the engine.

The object is to cool an engine in a hybrid vehicle having an engine and a rotating electric machine as a drive system and having a cooling pipe, a radiator, and a pump through which a liquid flows to cool the engine and the rotating electric machine, respectively. Forming a closed circuit independently of a circulation system and a circulation system for cooling the rotating electric machine, a heat exchanger for performing heat exchange between a circulation system for cooling the engine, a circulation system for cooling the rotating electric machine, and a liquid. It is achieved by having a configuration having.

[0008] The object of the present invention is to provide a hybrid vehicle having components such as an engine and a rotating electric machine as a drive system and having a plurality of cooling pipes and a radiator through which a liquid flows so as to cool the components. This is achieved by providing a heat exchanger between the upstream side of the engine in the system and the downstream side of the component in the circulation system for cooling components not including the engine.

It is an object of the present invention to provide a hybrid vehicle having, as a drive system, components such as an engine and a plurality of cooling pipes and a radiator through which a liquid flows so as to cool the components. This is achieved by having a flow path that bypasses the radiator and a thermostat that controls the flow rate of the radiator and the flow path that bypasses the radiator.

[0010] The object of the present invention is to provide a hybrid vehicle having, as a drive system, components such as an engine and a plurality of cooling pipes and a radiator through which a liquid flows so as to cool the components. This is achieved by having a configuration having a flow path that bypasses the heat exchanger. The object is to mount a component such as an engine as a drive system, and to bypass the radiator to a circulation system including the engine in a hybrid vehicle having a plurality of cooling pipes and a radiator through which a liquid flows to cool the component. This is achieved by providing a configuration having a flow path and a thermostat for controlling a flow rate of the radiator and a flow path that bypasses the radiator.

The object of the present invention is to detect a temperature of a component in a hybrid vehicle having, as a drive system, a plurality of cooling pipes and a radiator in which components such as an engine are mounted and a liquid flows to cool the component. And a means for controlling a flow path bypassing the radiator or the heat exchanger based on the detected signal.

An object of the present invention is to provide a hybrid vehicle having, as a drive system, components such as an engine and a plurality of cooling pipes and a radiator through which a liquid flows so as to cool the components. This is achieved by using a heat pipe that exchanges heat between a circulating system that includes the engine and a circulating system that does not include the engine, and by arranging the circulating system including the engine above the circulating system that does not include the engine.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS.

First, a hybrid vehicle according to the present invention will be described with reference to FIG. FIG. 8 illustrates an example of a configuration of a drive system of a hybrid vehicle. The engine 1 and the rotating electric machine 2 a are connected to a power switch 105, respectively, and transmit mechanical power to a drive shaft 103 and a drive wheel 102 via a differential reducer 104. Engine 1 and rotating electric machines 2a, 2b
Is controlled by an unillustrated integrated control unit mainly for the purpose of improving the fuel efficiency of the engine and reducing harmful components in the exhaust gas. The rotating electric machine 2a is supplied with electric power via a power converter 3 that converts a direct current supplied from a battery 8 into a three-phase alternating current having a variable voltage and a variable frequency.

Next, an operation example of the drive system will be described. For example, in an area where the engine speed is low, such as at the time of starting, or when the engine is not sufficiently warmed up, the rotating electric machine 2
a plays the role of a motor and drives alone. Also,
When the engine speed is in the high-speed region where fuel consumption is good, the engine 1 starts. At this time, the rotating electric machine 2a assists the driving of the engine 1 via the power switch during high-speed running, or operates the regenerative brake during deceleration to generate electric power, and stores the generated electric power in the battery 8. . Further, the engine 1 has another rotating electric machine 2b different from the rotating electric machine 2a, and controls a total of three power sources or power sources in a coordinated manner to improve fuel efficiency.

The engine 1, the rotating electric machine 2a, and the power converter 3 constituting the drive system of the hybrid vehicle described above.
Each of the components has a considerable amount of heat loss. Here, from the viewpoints of improving the fuel efficiency of the engine 1 and reducing the emission, and further, from the viewpoint of the fatigue life of the power element mounting portion in the power converter 3, each component is efficiently cooled and at the same time, the operation of the stopped component is performed. It is preferred to warm up using the heat loss of the components inside. For example, in the case of the engine 1, 20 to 30% of the energy of the fuel (about 15 kW in the case of an output of 60 kW) is generated as heat loss in the engine 1, and it is necessary to efficiently remove this heat. On the other hand, from the viewpoint of improving the fuel efficiency of the engine 1 and reducing the emission, it is desirable that the temperature of the cooling water of the engine 1 is always maintained at the 80 ° C. level. That is, it is necessary to remove generated heat while maintaining the engine 1 at an appropriate temperature. Also in the power converter 3, about 10% of the energy supplied from the battery 8 (3 kW for an output of 30 kW) is reduced. Since the heat is generated from the power element mounted in the power converter 3, it is necessary to efficiently remove this heat. On the other hand, from the viewpoint of the fatigue life of the solder and aluminum wire used for the mounting part of the power element,
It may be desirable to keep the temperature of the cooling water as low as possible while keeping it as constant as possible. Specifically, the temperature of the cooling water needs to be 60 ° C. or lower so as not to cause thermal runaway of the power element.

As described above, the amount of heat generated and the temperature level in each component are different from each other, and it is necessary to use a plurality of cooling systems in order to efficiently cool them. Under such a configuration, in order to warm up each component, a flow path for cooling each component has conventionally been connected via a valve or the like. There was a problem that control became difficult. Furthermore, these components need to be mounted on a vehicle, but there is a problem that it is difficult to make the whole compact. The hybrid vehicle cooling device according to the present embodiment, which will be described next, can satisfy these requirements.

Next, a first embodiment of a cooling device for a hybrid vehicle according to the present invention will be described with reference to FIGS. 1 is a configuration diagram of main components of a drive system of a hybrid vehicle of the present invention and a cooling system thereof, FIG. 2 is a detailed configuration diagram of a heat exchanger 4 in FIG. 1, and FIG. 3 is a temperature in the heat exchanger 4 in FIG. FIG. 4 is a flow chart showing a control method of the valve 9 in FIG.

In the present embodiment, the cooling system is composed of a circulation system 201 for cooling the engine 1 and a circulation system 202 for cooling the rotating electric machine 2 and the power converter 3. The independence of the cooling system is to utilize heat generated from the rotating electric machine 2 and the power converter during operation for warming up the engine while the engine is stopped. Further, the heat generation amount and the appropriate liquid temperature level of the engine 1 are different from those of the rotating electric machine 2 and the power converter 3.

First, cooling on the engine side will be described. In the engine cooling system 201, the engine 1, the radiator 5e, the heat exchanger 4, and the pump 6e are connected in series in this order. At this time, the thermostat 7e is disposed between the engine 1 and the radiator 5e, and a bypass flow path is formed between the radiator 5e and the heat exchanger 4 from this position. The thermostat 7e operates so that the coolant does not flow to the radiator 5e side at a low temperature and the coolant flows only to the bypass side at a low temperature after the threshold Te. Also, at high temperatures, the coolant does not flow to the bypass side, and the radiator 5e
Only flows to the side. The thermostat 7e has a certain width for the temperature for switching the flow direction, and before and after the threshold value Te, both of the flow paths 5e and 12e.
There is also a state in which the coolant flows.

The cooling system 201 operates the thermostat 7e so that heat loss immediately after the start of the engine 1 and heat absorption from the heat exchanger 4 do not pass through the radiator 5e. The coolant temperature can be raised to an appropriate temperature, and the coolant temperature can always be appropriately maintained even in an operation state in which the load fluctuates. The pump 6e is driven by a motor (not shown) and operates even when the engine 1 is stopped.

Next, the rotating electric machine 2 and the cooling system 202 of the power converter 3 will be described. The cooling system 202 includes a rotating electric machine 2, a power converter 3, a heat exchanger 4, a radiator 5,
m and the pump 6m are connected in series in this order. At this time, the thermostat 7m is disposed between the heat exchanger 4 and the radiator 5m, and a bypass flow path 12m is formed between the radiator 5m and the pump 6m from this position. The thermostat 7m operates such that the coolant does not flow to the radiator 5m side at a low temperature and the coolant flows only to the bypass side at a low temperature after the threshold value Tm. Also, at high temperature, the coolant does not flow to the side of the bypass flow path 12m, and the radiator 5m
Only flows to the side. The thermostat 7m has a certain width with respect to the temperature at which the flow direction is switched, and before and after the threshold value Tm, both the flow paths 5m and 12m are used.
There is also a state in which the coolant flows.

The cooling system 202 is operated by the rotating electric machine 2 and the power converter 3 by the operation of the thermostat 7m described above.
The cooling fluid temperature is raised to the cooling limit temperature Tmmax of the rotating electric machine 2 and the power converter 3 in as short a time as possible by avoiding the heat loss immediately after the start of the engine through the radiator 5e, and the engine-side warm-up is efficiently performed. It can be carried out.

The liquid used in both cooling systems is preferably an aqueous solution (antifreeze) containing ethylene glycol and a corrosion inhibitor as main components in consideration of the operation of a vehicle in a cold region.

Next, the heat exchange in the two cooling systems 201 and 202 will be described.

First, heat exchange at the time of starting will be described as a typical operation mode in a hybrid vehicle. At the start, the engine 1 is not warmed up,
The power converter 3 supplies power from a battery (not shown).
, The rotating electric machine 2 operates as a motor and starts.
At this time, in the cooling system 202, the temperature of the coolant circulated by the pump 6m gradually increases due to the heat generated from the power converter 3 and the rotating electric machine 2 described above. The coolant does not pass through the radiator 5m until the coolant temperature reaches the threshold value Tm of the thermostat 7m, so that the coolant rises in a short time. On the other hand, since the engine 1 is stopped in the cooling system 201 of the engine 1, there is no heat source in the system. However, since the pump 6e is operating, in the heat exchanger 4, the cooling system 2
02 is high, and the pump 6
Since e and 6m are operating, heat exchange occurs between the two liquids. That is, the heat of the liquid in the cooling system 202 is transmitted to the cooling system 201, the temperature of the liquid in the cooling system 201 rises, and the engine 1 is warmed.

FIG. 2 shows a detailed structure of the heat exchanger 4. The heat exchanger 4 has a flow path 1 connected to the cooling system side of the engine 1.
0 and a flow path 11 connected to the cooling system side of the rotary electric machine 2. The flow path surfaces of the respective flow paths are blocked by flow path walls, and perform heat exchange via the wall surfaces. In this drawing, the flow of the cooling liquid has a so-called "counterflow" configuration in which the flows flow from opposite directions, and the heat exchange efficiency is improved by adopting such a configuration. FIG.
Illustrates a so-called "dual heat exchanger", but various types of heat exchangers such as a shell-and-tube heat exchanger, a plate heat exchanger, or a compact heat exchanger are installed in the installation space. It can be appropriately selected and used depending on the amount of heat exchanged, the pressure loss, and the flow rate balance of the cooling liquids.

FIG. 3 is a graph showing a change in temperature of each cooling liquid in the heat exchanger 4. In the graph, the horizontal axis indicates the inlet / outlet of each cooling system. As each coolant flows downstream, the temperature of the rotating electric machine decreases and the temperature of the engine increases. The temperature gradient and the temperature difference of each cooling liquid are determined by the physical properties and flow rate of the cooling liquid and the heat transfer rate of the heat exchange unit. Further, as is clear from the figure, the temperature TEO at the outlet of the heat exchange portion of the engine coolant is at most equal to or lower than the inlet temperature TMI of the coolant at the rotating electrical machine side. The thermostat 7e on the engine side generally has a cooling limit temperature Tmma in the cooling system of the rotating electric machine 2 and the power converter 3.
Since the threshold value is larger than x, at least in a state where the engine 1 is stopped, the thermostat 7e on the engine side forms a flow path on the bypass side, and does not perform heat exchange in the radiator 5e.

Next, when the vehicle starts and reaches a certain vehicle speed range, the engine 1 starts and becomes a power source. At this time, since the engine 1 has already been warmed up to some extent by using the heat generated by the rotating electric machine 2 and the power converter 3 as described above, the engine 1 operates in a state of good fuel economy and low emission from the start. Will be. Further, in a higher-speed operation range, the engine 1 and the rotating electric machine 2 may operate at the same time and drive in cooperation. In this state, the engine itself is generating heat, does not pass through the radiator 5e until the liquid temperature reaches the threshold Te of the thermostat 7e, and the coolant rises in a short time.

In this case, the liquid temperature on the engine side may be higher than the liquid temperature on the rotating electric machine side. In this case, the heat generated by the engine moves to the rotating electric machine side, and the cooling limit of the rotating electric machine side becomes lower. The temperature may exceed Tmmmax. for that reason,
The valve 9 is controlled based on the flowchart shown in FIG.

As shown in FIG. 4, immediately after the start 301 (here, “start” refers to an operation in which the hybrid vehicle is brought into a state where it can be started by depressing an accelerator pedal), the rotating electric machine shown in FIG. The temperature Tmin on the upstream side of the valve 9 in the cooling system on the side and the temperature Tmout on the further downstream side where the bypass flow passage joins with the downstream side of the heat exchanger 4 are detected, and is Tmout a value larger than Tmin? It is determined whether or not (302). Regardless of the absolute value of the coolant temperature, when heat is received from the engine side, Tmout indicates a value greater than Tmin, the valve 9 is turned on (303), and the heat exchanger 4 is bypassed. Avoid receiving heat from On the other hand, when Tmout indicates a value smaller than Tmin, since heat is not received at least from the engine side, the heat exchanger 4 contributes to heat dissipation of the rotating electric machine 2 and the power converter 3, Turn valve 9 off
F (304), which passes through the heat exchanger 4.

As described above, according to the first embodiment of the cooling device for a hybrid vehicle of the present invention, in a plurality of cooling systems, the engine 1 can be quickly warmed up without complicating the control by piping valves. Can be. Further, when switching the flow path, there are very few parts that require an external signal such as temperature detection and the control algorithm is simple, so that a highly reliable cooling device can be constructed. Further, since there is no flow path that bypasses the heat-generating components such as the engine 1, the rotating electric machine 2, and the power converter 3, the flow rate in each cooling system can be kept substantially constant, and the cooling setting of each heat-generating component becomes easy. .

Next, a second embodiment of the cooling device for a hybrid vehicle according to the present invention will be described with reference to FIGS. FIG. 5 is a configuration diagram of main components and a cooling system of the drive system of the hybrid vehicle according to the present invention, and FIG. 6 is a detailed configuration diagram of the heat exchanger 4h in FIG.

This embodiment is different from the first embodiment in that
The difference is that a heat pipe type heat exchanger 4 h is adopted as the heat exchanger 4, and the valve is omitted in the cooling system 202 of the rotating electric machine 2.

FIG. 5 shows a detailed configuration diagram of the heat pipe type heat exchanger 4h. In the heat exchanger 4h, a cooling flow path 10 on the engine side is formed on the upper side with respect to the direction of gravity, and a cooling flow path 11 for the rotating electric machine 2 and the power converter 3 is formed on the lower side.
A plurality of heat pipes 13 are vertically arranged across the flow paths 10 and 11 via partition walls 15 separating 0 and 11,
Further, the heat pipe 13 has a number of fins 1 for heat exchange.
4 is attached. Here, a so-called wick that promotes the reflux of the condensed working fluid is not provided on the inner surface of the heat pipe 13. Next, the operation of the heat pipe type heat exchanger will be described. First, assuming that the engine 1 is warmed up, if the coolant temperature of the rotating electric machine 2 is higher than the coolant temperature of the engine 1, the heat pipe 13 is filled with the working fluid sealed in the heat pipe 13 in the evaporator 13a. Transports heat as latent heat to the condenser 13b by evaporation and boiling,
Further, the steam is condensed in the condensing section and returned as a working fluid to the lower evaporating section, so that the cooling passage 11 of the rotating electric machine 2 and the power converter 3 is moved to the cooling passage 10 of the engine 1. Can transmit heat.

The most significant feature of the present system is that the above operation does not occur when the temperature of the coolant on the engine side is higher than the temperature of the coolant on the rotating electric machine side. That is, when a high-temperature fluid exists in the upper part of the heat exchanger 4h and evaporates, even if it condenses in the lower part, the condensed working fluid cannot be refluxed in the upper part because there is no wick. Even if there is a wick, in a place where gravity is dominant, the capillary force flowing back against gravity is extremely small, and heat cannot be transported in practical use.

That is, by using the heat exchanger 4h of this system, the heat on the engine side cannot be transmitted to the rotating electric machine side, so that the valve 9 and the bypass passage required in the first embodiment are unnecessary. Thus, the engine can be quickly warmed up without using any signal control means.

In this sense, in the configuration of the heat pipe type heat exchanger 4h, the heat pipe 13 does not necessarily have to be vertically arranged, and at least the flow path on the engine side is at least as large as the flow path on the rotating electric machine side. A requirement is that it be located above.

Next, a third embodiment of the cooling device for a hybrid vehicle according to the present invention will be described with reference to FIG. FIG. 7 shows FIG.
5 is a flowchart showing a control method of the valve 9 in the first embodiment. This embodiment differs from the first embodiment in that the power converter 3 can be warmed up by changing the control method of the valve 9. As shown in FIG. 7, immediately after the start 301, the temperature Tmin on the upstream side of the valve 9 in the cooling system on the rotating electric machine side shown in FIG. The temperature Tmout on the further downstream side of the
It is determined whether the value is greater than min (3
02). Regardless of the absolute value of the coolant temperature, when receiving heat from the engine side, Tmout indicates a value greater than Tmin, and proceeds to the next determination 305. In 305, Tmin is detected, and it is determined whether or not Tmin is higher than the upper limit temperature Tmmax for cooling the rotating electric machine 3 and the power converter 2. Tmin is Tmm
If the value exceeds ax, if the heat from the engine side is received any more, cooling of the rotating electrical machine and the power converter becomes impossible, so the valve 9 is turned on (303) and the heat exchanger 4 is bypassed. So that heat from the engine side is not received. On the other hand, if Tmout shows a value smaller than Tmin, or even if Tmout shows a value larger than Tmin, as long as Tmin does not exceed Tmmax, the valve 9 is turned off (304) and the heat exchanger 4 is turned off. pass.

By performing such valve control,
In addition to warming up the engine 1, the power converter 3 can be warmed up, and the temperature fluctuation range of the temperature cycle that the power converter 3 receives can be reduced. That is, the life and reliability of the electric component can be improved.

Here, the movements of the valve and the thermostat have been described in detail. In addition, by controlling the driving force of the pump 6 in each cooling system, the engine can be warmed up in a short time or the power conversion can be performed. The temperature fluctuation range of the vessel can be reduced. Also, as for the combination of the component and the cooling system, if the configuration has a heat exchanger in two or more independent cooling systems, the warm-up and temperature adjustment of other components are basically performed using heat from the heat source. Is what you can do. For example, power storage means, such as batteries and fuel cells, are components that require cooling to generate heat themselves and that require temperature adjustment to improve output characteristics. Thus, the energy efficiency of the entire drive system can be improved.

[0042]

According to the cooling device for a hybrid vehicle of the present invention, the engine of the hybrid vehicle can be quickly warmed up, so that the fuel efficiency of the engine can be improved and harmful components in the exhaust gas can be reduced. In addition, the piping system and the control means can be simplified to make the whole compact. In addition, since it becomes possible to reduce the fluctuation range of the temperature cycle that the electric component receives, the life and reliability of the electric component can be improved.

[Brief description of the drawings]

FIG. 1 is a configuration diagram illustrating a cooling device for a hybrid vehicle according to a first embodiment of the present invention.

FIG. 2 is a detailed structural view of a heat exchanger in the cooling device of the hybrid vehicle according to the first embodiment of the present invention.

FIG. 3 is a diagram illustrating a temperature distribution of a heat exchanger in the cooling device of the hybrid vehicle according to the first embodiment of the present invention.

FIG. 4 is a flowchart illustrating a valve control method in the cooling device of the hybrid vehicle according to the first embodiment of the present invention.

FIG. 5 is a configuration diagram illustrating a cooling device for a hybrid vehicle according to a second embodiment of the present invention.

FIG. 6 is a detailed structural diagram of a heat pipe type heat exchanger in a cooling device for a hybrid vehicle according to a second embodiment of the present invention.

FIG. 7 is a flowchart illustrating a valve control method in the cooling device of the hybrid vehicle according to the third embodiment of the present invention.

FIG. 8 is a configuration diagram for explaining a drive system of the hybrid vehicle according to the first embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Engine, 2 ... Electric rotating machine, 3 ... Power converter, 4 ... Heat exchanger, 5 ... Radiator, 6 ... Pump, 7 ... Thermostat, 8 ... Battery, 9 ... Valve, 10 ... Engine side flow path, 11 ... Rotating electric machine side passage, 12 ... bypass passage, 1
3: heat pipe, 13a: heat pipe evaporator, 13
b: heat pipe condenser, 14: fin, 15: partition,
101: body, 102: drive wheel, 103: drive shaft, 10
4 ... Differential reducer, 105 ... Power switch, 201 ... Engine cooling system, 202 ... Cooling system for rotating electric machine and power converter,
Tmin: rotary electric machine side inlet temperature measurement sensor, Tmout
... Rotating electric machine side outlet temperature measurement sensor, Tmmmax ... Rotating electric machine / power converter allowable liquid temperature, TMI ... Rotating electric machine side heat exchanger inlet temperature, TMO ... Rotating electric machine side heat exchanger outlet temperature, TEI ... Engine side Heat exchanger inlet temperature, TEO ...
Outlet temperature of the engine side heat exchanger.

 ────────────────────────────────────────────────── ─── Continuing from the front page (72) Inventor Toshiyuki Inami 502-Jindachi-cho, Tsuchiura-city, Ibaraki Pref. Machinery Research Laboratory, Hitachi, Ltd. (72) Ryozo Masaki 7-1-1, Omika-cho, Hitachi, Ibaraki Hitachi, Ltd.Hitachi Laboratory (72) Inventor Toshimichi Minowa 1-1-1, Omika-cho, Hitachi, Ibaraki Prefecture, Ltd.Hitachi, Ltd.Hitachi Laboratory (72) Inventor Yoshimoge Oyama 2477 Takaba, Hitachinaka City, Ibaraki Prefecture Inside Hitachi Car Engineering Co., Ltd.

Claims (11)

[Claims] 1. A hybrid vehicle having a plurality of components, such as an engine and a rotating electric machine, mounted thereon as a drive system and having a plurality of cooling pipes and a radiator through which a liquid flows so as to cool each of the components. A cooling device for a hybrid vehicle, comprising: a heat exchanger that performs heat exchange between liquids in a circulation system and a circulation system that cools components not including the engine. 2. A circulating system for cooling an engine in a hybrid vehicle equipped with an engine and a rotating electric machine as a drive system and having a cooling pipe, a radiator, and a pump through which liquid flows to cool the engine and the rotating electric machine, respectively. Forming a closed circuit independently of a circulation system for cooling the rotating electric machine, and having a heat exchanger for performing heat exchange between a circulation system for cooling the engine, a circulation system for cooling the rotating electric machine, and liquid. A cooling device for a hybrid vehicle, characterized in that: 3. A heat exchanger is provided between an upstream side of an engine in a circulation system including the engine and a downstream side of a component in a circulation system for cooling components not including the engine. Item 1,
3. The cooling device for a hybrid vehicle according to any one of 2. 4. The cooling device for a hybrid vehicle according to claim 1, wherein a circulation path bypassing a radiator is provided in a circulation system that does not include the engine. 5. The cooling device for a hybrid vehicle according to claim 4, further comprising a thermostat that controls a flow rate of the radiator and a flow path that bypasses the radiator. 6. The cooling device for a hybrid vehicle according to claim 1, wherein the circulation system that does not include the engine has a flow path that bypasses a heat exchanger. 7. A circulating system including the engine has a flow path for bypassing a radiator.
The cooling device for a hybrid vehicle according to any one of claims 1 to 3. 8. A cooling device for a hybrid vehicle according to claim 7, further comprising a thermostat for controlling a flow rate of said radiator and a flow path bypassing said radiator. 9. The apparatus according to claim 5, further comprising means for detecting a temperature of the component, and means for controlling a flow path bypassing the radiator or the heat exchanger based on the detected signal.
The cooling device for a hybrid vehicle according to any one of claims 1 to 8. 10. The heat exchanger according to claim 1, wherein a heat pipe that exchanges heat between a circulation system including an engine and a circulation system not including an engine is used as the heat exchanger. 4. The cooling device for a hybrid vehicle according to claim 1. 11. The cooling device for a hybrid vehicle according to claim 10, wherein the circulation system including the engine is arranged above the circulation system not including the engine.