JPH0988599A - Cooling water temperature control device for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the excess increase of a water temperature during the stop of an engine right after high load running in the summer season without operating a motor-driven cooling fan. SOLUTION: A motor-driven water pump 14 to circulate cooling water to a heater core 7 for heating is arranged at the cooling system circuit of a water- cooled type engine 1 and a control device 19 is provided to control operation of the heater valve 13 of the heater core 7 for heating and the motor-driven water pump 14. When a cooling water temperature is higher than a set temperature during the stop of the water-cooled engine 1, a signal from a water temperature sensor 17 is received, and the heater valve 13 is opened by the control device 19, and by operating the motor-driven water pump 14, low temperature cooling water in a flow passage on the heater core 7 side for heating is circulated to the water-cooled engine 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention can favorably prevent, in a vehicle equipped with a water-cooled engine (internal combustion engine), an excessive rise in cooling water temperature during dead soak of the vehicle (when the engine is stopped immediately after running under high load). And a cooling water temperature control device.

[0002]

2. Description of the Related Art Usually, a water pump mechanically driven by a crankshaft of an engine is provided in a cooling system of a vehicle running engine, and this water pump circulates cooling water in a cooling system circuit. There is.
In addition, in some vehicles, in addition to the mechanically driven water pump, a small electric water pump is installed, and a system in which the electric water pump mainly circulates cooling water to the heater core for heating is adopted. There is.

[0003]

By the way, in the latter system described above, in order to prevent the coolant temperature from excessively rising during dead soak of the vehicle (when the engine is stopped immediately after running under a heavy load), the electric power is supplied to the engine even when the engine is stopped. Continue the operation of the water pump to supply cooling water to the engine, radiator,
It has also been proposed to circulate in a main cooling system circuit including a thermostat and a thermostat.

However, especially in the dead soak immediately after running under high load in summer, the water temperature of each part of the main cooling system circuit is at a considerably high level, so that the effect of lowering the water temperature is obtained even if the cooling water is circulated by the electric water pump. There is a problem that it is small and it is not possible to sufficiently prevent an excessive rise in the cooling water temperature. Therefore, it is possible to combine the operation of the electric water pump with the operation of the electric cooling fan of the radiator.In this case, when the engine is stopped, the on-vehicle battery is used as the power source to operate both the electric water pump and the electric cooling fan. As a result, the vehicle-mounted battery may be over-discharged.

The present invention has been made in view of the above points,
An object of the present invention is to make it possible to prevent an excessive rise in the cooling water temperature immediately after running under a high load such as in the summer, without requiring the operation of the electric cooling fan.

[0006]

In order to achieve the above object, the present invention employs the following technical means. In the present invention,
When traveling under a high load such as in summer, the cooling load of the vehicle air conditioner is large, so that the circulation of the cooling water to the heating heater core is stopped, and the heating heater core is blown with the cool air cooled by the cooling heat exchanger. Installed in the air-conditioning duct, paying attention to the fact that the cooling water temperature inside the heating heater core is maintained at a relatively low temperature under the influence of this cold air, and during the dead soak, the low-temperature cooling water in the heating heater core side flow passage is By circulating it in the engine, the above object is achieved.

Specifically, in the invention according to claims 1 and 2, an electric water pump (14) for circulating cooling water to the heating heater core (7) is provided in the cooling system circuit of the water-cooled engine (1). A control device (19) for controlling the operation of the heater valve (13) and the electric water pump (14) is also provided, and when the cooling water temperature is higher than the set temperature when the water-cooled engine (1) is stopped, the control device ( 19)
This opens the heater valve (13) and
The electric water pump (14) is operated to circulate the low-temperature cooling water in the heating heater core (7) side passage to the water-cooled engine (1).

According to the first and second aspects of the invention, when the cooling water temperature is higher than the set temperature when the water-cooled engine (1) is stopped, the controller (19) controls the heater valve (1).
3) The valve is opened and the electric water pump (1
4) is operated to circulate the low-temperature cooling water in the heating heater core (7) side flow path to the water-cooled engine (1). The rise can be well prevented.

Moreover, since it is not necessary to operate the electric cooling fan which consumes a large amount of power after the engine is stopped, there is no fear of over-discharge of the vehicle battery. Further, since it is possible to prevent the cooling water temperature from excessively rising during dead soak, it is possible to reduce the pressure resistance of the cooling system circuit component, and it is possible to reduce the cost and weight of the product by reducing the thickness of the cooling system circuit component.

According to the third and fourth aspects of the invention, the heater bypass circuit (23) for bypassing the heating heater core (7) and flowing the cooling water to the radiator (2) in the cooling system circuit of the water-cooled engine (1). And a heater valve (13) provided in the cooling system circuit of the water-cooled engine (1),
Heating heater core (7) and heater bypass circuit (2
A three-way valve type that controls the flow of cooling water to 3) is provided, and an electric water pump (14) that circulates the cooling water to the heating heater core (7) is provided in the cooling system circuit of the water-cooled engine (1). , A controller (19) for controlling the operation of the heater valve (13) and the electric water pump (14) is provided, and when the cooling water temperature is higher than the set temperature during the idle operation of the water-cooled engine (1), the controller ( 19) operates the heater valve (13) to a position where the flow of cooling water to the heater core for heating (7) is restricted and the cooling water flows to the heater bypass circuit (23), and the electric water pump (14) The cooling water flows into the radiator (2) through the heater bypass circuit (23) so that the cooling water temperature is higher than the set temperature when the water cooling engine (1) is stopped. When the control unit (19)
The heater valve (13) is operated so that the flow of cooling water to the heater bypass circuit (23) is shut off and the cooling water flows to the heater core (7) for heating, and the electric water pump (14) is operated. The low temperature cooling water in the heating heater core (7) side flow path is circulated in the water-cooled engine (1).

Therefore, according to the invention described in claims 3 to 4, not only can the cooling water temperature be prevented from rising excessively during dead soak, but also the cooling water temperature can be set below the set temperature during idle operation of the water-cooled engine (1). When the temperature is high, the controller (19) operates the heater valve (13) to a position where the cooling water flows through the heater bypass circuit (23), and the electric water pump (14) is operated to operate the heater bypass circuit (13). Since the cooling water is flowing into the radiator (2) through 23), the amount of cooling water flowing into the radiator is increased to increase the radiator cooling capacity, and the excessive rise of the cooling water temperature during idle operation is also effectively prevented. it can.

Further, in the invention described in claim 5, the water-cooled engine (1) has a fuel cooler (25) for cooling the fuel system parts for supplying the fuel to the water-cooled engine (1) with cooling water. When the cooling water temperature is higher than the set temperature at the time of the stop of (), the cooling water in the heating heater core (7) side flow path is circulated to the water-cooled engine (1) and the fuel cooler (25). The fuel cooler 25 can cool the fuel in the fuel supply pipe 26 and the fuel injection valve 27. As a result, it is possible to reliably prevent the cooling water temperature from excessively rising due to dead soak, and at the same time suppress the generation of bubbles in the fuel to improve the restartability of the engine 1.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. (First Embodiment) In FIG. 1, reference numeral 1 denotes a running engine (internal combustion engine) of a vehicle, which is of a water cooling type. A radiator 2 cools the cooling water by exchanging heat between the cooling air blown by the cooling fan 3 and the cooling water of the internal combustion engine 1. Here, the cooling fan 3 is composed of an electric axial fan driven by a motor 3a.

Reference numeral 4 is a bypass circuit provided in parallel with the radiator 2 and reference numeral 5 is a thermostat (cooling water temperature responsive valve) for controlling the flow of cooling water to the radiator 2 and the bypass circuit 4. By utilizing the change, the valve body (not shown) is displaced to switch the cooling water flow path. Specifically, when the cooling water temperature is low, the thermostat 5 opens the bypass circuit 4 side to allow the cooling water to flow to the bypass circuit 4 side, while the cooling water temperature rises to a predetermined temperature (for example, 80 ° C) or higher. Then, the thermostat 5 opens the radiator 2 side and closes the bypass circuit 4 side, thereby cooling the cooling water in the radiator 2.

A water pump 6 circulates cooling water in a cooling system circuit of the engine 1 and is mechanically driven by transmitting the rotation of the crankshaft of the engine 1 to a pulley 6a. Reference numeral 7 denotes a heater core (heating heat exchanger) of an automobile air conditioner, which heats the conditioned air blown by the air conditioning blower 8 shown in FIG. 2 by exchanging heat with the cooling water. The heater core 7 is installed in the air passage in the air conditioning duct 9 on the air downstream side of the cooling evaporator 10, and reheats the cold air cooled by the evaporator 10 to a predetermined temperature to blow air into the vehicle interior. Control the temperature. The blower 8 is composed of an electric centrifugal fan driven by a motor 8a.

Reference numeral 11 is an air inlet for sucking air through an inside / outside air switching box (not shown), and 12 is an outlet for blowing out the air whose temperature is controlled by the heater core 7 into the passenger compartment, which is a face for blowing air toward the passenger's head. An air outlet, a foot air outlet that blows air toward the foot of the occupant, a defroster air outlet that blows air toward the vehicle window glass, and the like are provided.

A heater valve 13 is installed in the cooling water inlet side flow path of the heater core 4, and is an opening / closing valve for controlling the flow of cooling water to the heating heater core 7. A valve body (not shown) of the heater valve 13 is opened and closed by an electric actuator 13a such as a servomotor or an electromagnetic drive mechanism. In this example, the opening degree of the valve body (not shown) of the heater valve 13 is adjusted by the actuator 13a,
A reheat type temperature control method is adopted in which the amount of cooling water flowing into the heater core 7 is controlled to control the reheat amount of air by the heater core 7 to control the temperature of blown air.

Reference numeral 14 denotes an electric water pump installed in the cooling water inlet side flow passage of the heater valve 13, which is driven by a motor 14a. Reference numeral 15 is an air conditioning switch group provided on a control panel (not shown) of an automobile air conditioning system, which is an air conditioning switch for starting an air conditioning compressor (not shown), a temperature setting switch for setting a target temperature, and a blowout mode. A switch, a control switch of the blower 8 and the like. Reference numeral 16 denotes a sensor group for automatic control of an automobile air conditioner, which detects an inside air temperature sensor for detecting a vehicle interior temperature, an outside air temperature sensor for detecting an outside air temperature, a solar radiation sensor for detecting a solar radiation amount, and a cooling temperature of the evaporator 10. It includes an evaporator temperature sensor and the like.
In the present example, the air conditioning switch group 15 and the sensor group 16 constitute "air conditioning signal means".

Reference numeral 17 denotes a water temperature sensor for detecting the temperature of the cooling water at the cooling water outlet of the engine 1, which is composed of a temperature sensitive resistance element such as a thermistor. In this example, the water temperature sensor 17 constitutes "water temperature signal means for generating a signal related to the cooling water temperature". Reference numeral 18 is an ignition switch that supplies power to the ignition circuit of the engine 1. In this example, the ignition switch 18 constitutes "engine signal means for generating signals related to the operation and stop of the engine 1."

Reference numeral 19 denotes an electronic control unit composed of a microcomputer and its peripheral circuits, which are preset with input signals input from the air conditioning switch group 15, the sensor group 16, the water temperature sensor 17, the ignition switch 18, and the like. Judgment and arithmetic processing are performed according to a program, and the blower 8, based on the arithmetic processing result,
The operation of the heater valve 13, the electric water pump 14, etc. is controlled.

Reference numeral 20 denotes a refrigerant condenser of a refrigeration cycle of an air conditioner for a vehicle, which is installed on the air upstream side of the radiator 2 (front side of the vehicle), and is cooled by a common cooling fan 3 together with the radiator 2. Reference numeral 21 is a main circuit for circulating cooling water to the radiator 2 side, and 22 is a heater sub-circuit for circulating cooling water to the heater core 7 side. Arrows A and B indicate cooling water flow directions in the main circuit 21 and the sub circuit 22, respectively.

Next, the operation of the above configuration will be described.
While the vehicle is running in the summer, when the vehicle interior is being cooled by the air conditioner, the heater valve 13 is shut off by the output of the electronic control unit 19 to the heater core 7, that is, the fully closed position, that is, the maximum cooling position. It is operated to the (max cool position) or to a minute opening position (a position near maximum cooling) in which a very small amount of cooling water flows into the heater core 7.

When the air conditioner is in the maximum cooling state, since the heater valve 13 is in the fully closed position as described above, the electric water pump 14 is stopped by the output of the electronic control unit 19. Therefore, the heater sub-circuit 2
The temperature of the cooling water of No. 2 only rises due to heat conduction from the main circuit 21, and the cold air cooled by the evaporator 10 passes through the heater core 7. The temperature is kept much lower than that of the cooling water on the circuit 21 side.

When the air conditioner is in the vicinity of maximum cooling, the heater valve 13 is operated to the minute opening position as described above by the output of the electronic control unit 19, so that the electric water pump 14 operates. It becomes a state. As a result, the cooling water circulates in the heater core 7,
Since the flow rate of the cooling water flowing into the heater core 7 is very small and the cold air cooled by the evaporator 10 passes through the heater core 7, even in this state, the cooling water in the portion from the middle of the heater core 7 to the outlet side is Becomes cold.

On the other hand, the flow of cooling water for cooling the water-cooled engine 1 returns from the engine 1 to the engine 1 through the radiator 2, thermostat 5 and mechanical drive water pump 6 as shown by arrow A. Circulate. At this time, the thermostat 5 fully closes the bypass circuit 4 and fully opens the main circuit 21 side. Radiator 2
In, the cooling air is forcedly blown by the operation of the cooling fan 3 to cool the cooling water.

Under high-load running conditions in the summer, for example, when the vehicle is running on a low-speed hill when the outside temperature is high, the heat generation amount of the engine 1 increases and the heat radiation amount of the condenser 20 increases due to the increase of the cooling load. Since the radiator 2 inflow air temperature rises and the cooling capacity of the radiator 2 tends to be insufficient, the cooling water temperature is generally very high,
Often exceeds 100 ° C.

As described above, the vehicle is stopped and the ignition switch 1
When 8 is opened and the engine 1 is stopped (during so-called dead soaking), the cooling fan 3 is stopped and the radiator 2
Since the cooling action of 1 is stopped, the temperature of the cooling water may excessively rise due to the amount of heat of the engine 1.

However, in the first embodiment, when the open signal of the ignition switch 18 is input (when the engine 1 is stopped), the cooling water temperature of the engine 1 detected by the water temperature sensor 17 is set to the set temperature (this example). Then 100 °
If it is C) or more, the control device 19 determines this condition, operates the electric water pump 14, and opens the heater valve 13. As a result, the cooling water in the heater sub-circuit 22 circulates in the engine 1 even when the engine 1 is stopped.

Here, as described above, the cooling water in the heater sub-circuit 22 is much lower in temperature than the cooling water in the main circuit 21, so that this low-temperature cooling water enters the engine 1. By circulating the heat, the heat of the engine 1 can be effectively absorbed, and thus it is possible to reliably prevent an excessive rise in the cooling water temperature due to dead soak. In addition, when the cooling water temperature of the engine 1 is below the set temperature (100 ° C. in this example), there is no possibility of excessive rise of the cooling water temperature.
Do not operate the electric water pump 14.

FIG. 3 shows the effect of the present invention described above. In the prior art in which the electric water pump 14 is not operated during dead soak, the cooling water temperature rises to about 115 ° C. Low temperature cooling water in the heater sub-circuit 22 (75 ° at the heater core 7 outlet water temperature
The temperature of the cooling water could be suppressed to about 106 ° C, which is 9 ° C lower than that of the conventional technique, by circulating (C to 76 ° C) to the engine 1. In the experiment of FIG. 3, the circulating flow rate of the cooling water by the electric water pump 14 is 7 liters / minute.

FIG. 4 shows the behavior of the cooling water temperature during dead soak in each portion of the engine cooling system circuit in the prior art, and FIG. 5 shows the behavior of the cooling water temperature during dead soaking in each portion of the engine cooling system circuit according to the present invention. .
In the prior art, the electric water pump 14 at the time of dead soak
Since it does not operate, the low temperature (75 °
An extremely large temperature distribution of about 40 ° C. occurs between the cooling water of C to 76 ° C.) and the high temperature cooling water of the main circuit 21. Each component of the engine cooling system circuit must have its thickness, shape, etc. set so that it can withstand the maximum temperature, resulting in high cost of the product.

However, according to the present invention, the temperature distribution can be reduced to about 3 ° C. by circulating the low temperature cooling water in the heater sub-circuit 22, as shown in FIG. By preventing the temperature rise and making the temperature distribution uniform, the design criteria such as pressure resistance and heat resistance of each component of the cooling system circuit can be relaxed, and the product cost can be reduced. (Second Embodiment) FIG. 6 shows a second embodiment. In this example, as the cooling fan of the radiator 2, instead of the electric cooling fan 3 in the first embodiment, a pulley 30a from the crankshaft of the engine 1 is used. This is a case of using a mechanical drive type cooling fan (tempo fan) 30 that receives rotational power via and rotates.

As described above, the mechanical drive type cooling fan 30
When the engine is used, the rotation speed of the cooling fan 30 decreases with the decrease in the engine rotation speed even during the idle operation (during hot soak) immediately after running under high load,
In some cases, the cooling capacity of the radiator 2 may become insufficient, and the temperature of the cooling water may rise excessively. Therefore, in this example, it is possible to prevent the water temperature from excessively rising during the hot soak, and for that purpose, the heater bypass circuit 23 that directly connects the upper tank 2a of the radiator 2 and the heater valve 13 is additionally installed, and The heater valve 13 has a three-way valve structure.
The flow of cooling water to both the heater bypass circuit 23 and the heater bypass circuit 23 can be controlled.

The control device 19 is connected to a rotation speed sensor 24 for inputting the engine rotation speed signal Ne. In the present example, the rotation speed sensor 24 constitutes "idle signal means for generating a signal indicating that the water-cooled engine 1 is in an idle operation state", but a vehicle speed sensor or the like is used as the idle signal means. It can also be used.

According to the second embodiment, the water-cooled engine 1 enters the idle operation state immediately after running under high load in the summer, and the engine cooling water temperature rises above the set temperature (100 ° C.) to cause the hot soak state. Then, based on the input signal from the rotation speed sensor 24 and the input signal from the water temperature sensor 17, the control device 19 decreases the engine rotation speed to below the set rotation speed, and the cooling water temperature exceeds the set temperature (100 ° C). It is determined that the temperature has risen to 0, and it is determined that the hot soak state.

As a result, the control device 19 activates the electric water pump 14 and, at the same time, the heater valve 13
Is operated to a position where the flow of cooling water to the heater core 7 is restricted and the cooling water flows to the heater bypass circuit 22. As a result, the operation of the electric water pump 14 causes the engine 1
From the heater valve 13, most of the cooling water flowing from the heater sub-circuit 22 into the heater bypass circuit 23 flows into the upper tank 2a of the radiator 2.

Then, in the upper tank 2a of the radiator 2, the cooling water from the main circuit 21 merges and passes through the radiator 2. Therefore, the amount of cooling water flowing into the radiator 2 increases by the amount of cooling water flowing in from the heater bypass circuit 23 due to the operation of the electric water pump 14, and the cooling capacity increases correspondingly. Due to this increase in cooling capacity, it is possible to favorably prevent an excessive rise in water temperature during hot soak.

On the other hand, at the time of dead soak, the control device 19
The electric water pump 14 is activated by the
The heater valve 13 is operated to a position where the cooling water flow to the heater bypass circuit 23 is shut off and the cooling water flows to the heater core 7. With this, similarly to the first embodiment, it is possible to favorably prevent the water temperature from excessively increasing during dead soak. Note that the heater valve 13 may be operated so as to completely block the flow of the cooling water to the heater core 7 during hot soaking. Thus, the heater valve 13 during hot soaking
Even if is operated to limit (block) the flow of the cooling water to the heater core 7, the air conditioning feeling is not impaired because the air conditioner is in the cooling state during hot soak. (Third Embodiment) FIGS. 7 and 8 show a third embodiment in which fuel system parts can be cooled during dead soak.

When the engine 1 is operated under a high load, is stopped at a high temperature, and is then restarted, the heat from the engine 1 affects the fuel system parts, mainly the fuel. Part of the fuel (gasoline) remaining in the supply pipe (fuel distribution pipe) and fuel injection valve is vaporized to generate bubbles (vapor), and the actual fuel supply amount will decrease at the next engine start. As a result, engine start failure occurs.

In view of such a problem, in the third embodiment, the fuel system parts can be cooled by using the low temperature cooling water on the heater core 7 side during dead soak.
In FIGS. 7 and 8, reference numeral 25 denotes a fuel cooler, which is formed of metal or resin into a cylindrical shape, and a cylindrical fuel supply pipe 26 is concentrically formed at the center of the cylindrical fuel cooler 25. It is located and stored in. A fuel injection valve 27 for injecting fuel into the intake manifold 1a of the engine 1 is integrally connected to the fuel supply pipe 26, and a plurality of fuels (in FIG. It is adapted to be distributed to the four fuel injection valves 27.

The fuel injection valve 27 penetrates the circumferential surface of the fuel cooler 25 and is attached to the intake manifold 1a. Here, the injection valve through hole portion on the circumferential surface of the fuel cooler 25,
And the connection portion between the fuel supply pipe 26 and the fuel injection valve 27 is
It is sealed with a sealing material (not shown) to prevent fuel and cooling water from leaking. A cooling water inlet pipe 25a is provided at one end of the fuel cooler 25 in the axial direction.
An outlet pipe 25b of cooling water is provided at the other end, the inlet pipe 25a is connected to a three-way valve type heater valve 13 on the outlet side of the heater core 7 via a flow passage 28, and the outlet pipe 25b is passed via a flow passage 29. Machine driven water pump 6
It is connected to the suction side of.

When the engine is stopped after high load operation,
When the cooling water temperature detected by the water temperature sensor 17 is equal to or higher than the set temperature (100 ° C. in this example), the control device 19 determines the dead soak state based on the detection signal of the water temperature sensor 17 and the open signal of the ignition switch 18. Then, the electric water pump 14 is operated and the heater valve 13 is operated to open the flow path 28 side.
As a result, even when the engine 1 is stopped, the cooling water in the heater sub-circuit 22 passes through the flow path 28, the fuel cooler 25,
And it will circulate in the engine 1 through the flow path 29.

Here, as described above, the cooling water in the heater sub-circuit 22 is much lower in temperature than the cooling water in the main circuit 21, so this low-temperature cooling water is the fuel cooler 25. By circulating the fuel in the engine 1, it is possible to cool the fuel in the fuel supply pipe 26 and the fuel injection valve 27 in the fuel cooler 25. As a result, the generation of bubbles in the fuel can be suppressed and the restartability of the engine 1 can be improved. At the same time, since the heat of the engine 1 can be effectively absorbed, it is possible to reliably prevent the coolant temperature from excessively rising due to dead soak. (Fourth Embodiment) FIG. 9 shows the heater valve 13 as the second embodiment of FIG.
This is an example in which it is arranged on the upstream side of the heater core 7 as in the embodiment, and the other points are the same as in the third embodiment. According to the fourth embodiment, since the cooling water cannot be circulated through the heater core 7 during the dead soak, the cooling effect is lower than that of the third embodiment, but the low-temperature cooling water in the heater sub-circuit 22 is supplied to the fuel cooler 25. Also, by circulating in the engine 1, it is possible to prevent the fuel from being cooled and the temperature of the cooling water from rising excessively. (Other Embodiments) As a vehicle air conditioner, FIG. 2 shows a reheat type air conditioner in which the amount of cooling water to the heater core 7 is adjusted by the heater valve 13 to control the air temperature in the vehicle interior. 7 is provided with a bypass ventilation passage, and the air volume ratio to the bypass ventilation passage and the heater core 7 is adjusted by the opening degree of the air mixing door to control the temperature of the air blown into the passenger compartment. The invention can be implemented.

[Brief description of drawings]

FIG. 1 is a circuit diagram of a cooling system of a vehicle water-cooled engine showing a first embodiment of the present invention.

FIG. 2 is a schematic configuration diagram of a ventilation system of the vehicle air conditioner according to the first embodiment.

FIG. 3 is a graph showing the behavior of engine water temperature during dead soak.

FIG. 4 is a graph showing the temperature distribution of each part of the cooling system circuit during dead soak in the conventional device.

FIG. 5 is a graph showing the temperature distribution of each part of the cooling system circuit during dead soak in the device of the present invention.

FIG. 6 is a cooling system circuit diagram of a vehicle water-cooled engine showing a second embodiment of the present invention.

FIG. 7 is a cooling system circuit diagram of a vehicle water-cooled engine showing a third embodiment of the present invention.

8 is a sectional view taken along the line DD of FIG. 7;

FIG. 9 is a cooling system circuit diagram of a vehicle water-cooled engine showing a fourth embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Water-cooled engine, 2 ... Radiator, 3 ... Electric cooling fan, 5 ... Thermostat, 6 ... Mechanical drive water pump, 7 ... Heater core, 13 ... Heater valve, 14 ... Electric water pump, 18 ... Ignition switch, 19
... control device, 25 ... fuel cooler.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Mitsuru Inoue 1-1, Showa-cho, Kariya city, Aichi Prefecture Nihondenso Co., Ltd.

Claims (5)

[Claims] 1. A heating heater core (7) provided in a cooling system circuit of a water-cooled engine (1) for heating air using cooling water as a heat source, and a cooling system circuit of the water-cooled engine (1). A heater valve (13) for controlling the flow of cooling water to the heating heater core (7) and a cooling system circuit of the water-cooled engine (1) to supply cooling water to the heating heater core (7). An electric water pump (14) that circulates, and a controller (19) that controls the operation of the heater valve (13) and the electric water pump (14) are provided, and cooling water is provided when the water-cooled engine (1) is stopped. When the temperature is higher than the set temperature, the heater valve (13) is opened by the control device (19) and the electric water pump (14) is operated to perform the heating operation. Stator core (7) side channel vehicular cooling water temperature control device according to claim cooling water circulating in the water-cooled engine (1). 2. The control device (19) generates engine signal means (18) for generating a signal related to the operation and stop of the water-cooled engine (1), and a signal related to the cooling water temperature. A water temperature signal means (17) and an air conditioning signal means (15, 15) for generating a control signal for the vehicle air conditioner.
16. The vehicle cooling water temperature control device according to claim 1, wherein a signal is input from 16). 3. A mechanically driven water pump (6), which is driven by a water-cooled engine (1) and circulates cooling water in a cooling system circuit of the water-cooled engine (1), and the water-cooled engine (1). A radiator (2) provided in the cooling system circuit for cooling the cooling water, and a heating heater core (7) provided in the cooling system circuit of the water-cooled engine (1) for heating air using the cooling water as a heat source. A heater bypass circuit (23) that bypasses the heating heater core (7) and causes cooling water to flow to the radiator (2).
And a three-way valve type heater valve (13) provided in a cooling system circuit of the water-cooled engine (1) and controlling the flow of cooling water to the heating heater core (7) and the heater bypass circuit (23). An electric water pump (14) provided in the cooling system circuit of the water-cooled engine (1) for circulating cooling water to the heater core (7) for heating, the heater valve (13) and the electric water pump (14) ) For controlling the operation of the heater valve (13) when the cooling water temperature is higher than a preset temperature during idle operation of the water-cooled engine (1). ) Is operated to a position where the flow of cooling water to the heater core (7) for heating is restricted and the cooling water flows to the heater bypass circuit (23). The water pump (14) is operated to allow the cooling water to flow into the radiator (2) through the heater bypass circuit (23), and when the cooling water temperature is higher than the set temperature when the water-cooled engine (1) is stopped, The controller (19) operates the heater valve (13) to a position where the cooling water flow to the heater bypass circuit (23) is shut off and the cooling water flows to the heating heater core (7). A vehicle cooling water temperature control device, characterized in that the electric water pump (14) is operated to circulate the cooling water in the heating heater core (7) side flow path to the water cooling engine (1). 4. The control device (19) has an engine signal means (18) for generating a signal related to the operation and stop of the water-cooled engine (1), the water-cooled engine (1).
The idle signal means (24) for generating a signal indicating that the vehicle is in an idle operation state, the water temperature signal means (17) for generating a signal related to the cooling water temperature, and the control signal for the vehicle air conditioner. Air conditioning signal means (15,
The vehicle cooling water temperature control device according to claim 3, wherein a signal is input from 16). 5. A fuel cooler (2) for cooling a fuel system component for supplying fuel to the water-cooled engine (1) with cooling water.
5), and when the cooling water temperature is higher than a set temperature when the water cooling engine (1) is stopped, the cooling water in the heating heater core (7) side flow path is supplied to the water cooling engine (1) and the cooling water. Circulation through a fuel cooler (25).
5. The vehicle cooling water temperature control device according to any one of 1 to 4.