JPS6131286B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a control device for an engine cooling system.

In recent years, winter outside temperatures for automobiles, etc. have fallen from -25 to -25.
It is desired to be able to maintain a comfortable heating effect even when the temperature drops to around -30℃, and conversely, even when driving in traffic jams in the summer, there will be no engine trouble due to a rise in the temperature inside the engine compartment, and in addition, the cap It is desired to suppress fuel evaporation from the fuel as much as possible.

In order to improve the heating effect, it is possible to satisfy this request by setting the temperature of the engine coolant, which is the hot wire of the heating system, higher, but this would have an extremely negative effect on the above request in the summer. .

It is an object of the present invention to provide a device that can satisfy both of the above-mentioned mutually exclusive demands. The embodiments shown in the accompanying drawings will be described below.

In FIG. 1, 1 is an engine, 2 is a radiator, and 3 is a pump. Engine coolant passes through the engine 1 by the pump 3, removes its heat, passes through a circulation pipe 6, and reaches the radiator 2. The heat is radiated and sent back to the engine 1 through the circulation pipe 7, and the engine 1 is cooled by repeating this circulation.

A thermostat case 10 is interposed between the outlet section 1a of the engine coolant from the engine 1 and the connection section of the circulation pipe 6, and a thermostat case 10 is provided in the case 10 to open the thermostat when the coolant temperature exceeds a predetermined value. A thermostatic valve 5 is installed to allow the coolant that has cooled the engine to flow through the circulation pipe 6 to the radiator 2.

A coolant outlet 1b is provided for taking out the coolant from a further upstream part of the coolant outlet 1a of the engine 1, and the coolant flowing out from the outlet 1b passes through coolant passages 9a, 9b, 9c and 9d into the thermos. It flows into the upstream chamber 10a of the thermostatic valve 5 of the thermostat case 10, passes through there, and is fed into the engine 1 by the pump 3 through the passage 9e.

A heater core 4 for a heating device is connected to the coolant passage 9b in parallel through passages 4a and 4b, and a heater cock 8 is provided at the entrance of the passage 4a, and by switching the heater cock 8, the cooling liquid is supplied to the passage. 9a to the heater core 4 side.

A specific example of the structure of the thermostat valve 5 and the thermostat case 10 is shown in FIG.

That is, as shown in FIG. 2, the thermostatic valve 5 includes a temperature-sensing section 5a mounted and supported within the case 10, and a valve that opens and closes the outlet and inlet of the case 10, respectively, by the operation of the temperature-sensing section 5a. body 5
b and 5c, and when the coolant temperature in case 10 is below the set value, valve bodies 5b and 5c are connected to case 1.
When the temperature of the coolant inside the case 10 exceeds a predetermined value, the valve elements 5b and 5c are opened by the temperature sensor 5a.

The operation of the above configuration will be explained below.

In the summer when heating is not performed, the heater cock 8 is rotated 90 degrees in the direction of the arrow from the state shown in the first figure, so that the passages 9a and 9b are in communication with each other, and the thermostat valve 5 is closed while the coolant temperature is low. Since it is in the closed state, the coolant that cooled the engine 1 flows from the outlet 1b to the coolant passages 9a, 9b, 9c, 9.
d through the chamber 10 in the thermostat case 10.
a, is sucked into the pump 3 through the passage 9e, and is supplied to the engine 1 again. A part of the coolant flowing through the passage 9c is directly sucked into the pump 3 through the passage 9f, but an orifice 11 is provided in the passage 9f to restrict the flow rate of the coolant flowing through the passage 9f. Therefore, most of the coolant passes through the thermostat case 10 as described above.

When the temperature of the engine coolant increases and the temperature of the coolant passing through the thermostat case 10 reaches a predetermined value, the thermostat valve 5 operates and the valve body 5
b and 5c open together.

Then, the coolant that cooled the engine 1 flows into the outlet section 1.
From a, it flows through the case 10 through the circulation pipe 6 and reaches the radiator 2, where it is cooled by heat radiation, and the engine 1 that flows into the engine 1 from the circulation pipe 7 via the pump 3 is cooled.

In the above, the opening operation of the thermostat valve 5 is performed by the temperature of the coolant, which naturally radiates heat while passing through the coolant passages 9a, 9b, 9c, and 9d, and whose temperature has decreased somewhat from the outlet port 1b. However, in summer when heating is not used, the outside temperature is high and the coolant temperature drop due to natural heat radiation is extremely small, so the coolant temperature flowing inside the case 10 is not much different from the coolant temperature of the engine 1, and the thermostat It cannot be assumed that the valve 5 operates by sensing a temperature approximately equal to the temperature of the coolant in the first part of the engine.

If the above-mentioned natural heat radiation of the coolant becomes a problem, heating failure can be avoided by setting the set temperature of the temperature sensing part 5a of the thermostat valve 5 to a temperature lowered by the temperature drop of the coolant due to the natural heat radiation. It is possible to control the engine temperature during use to a low level as before, and prevent various troubles due to engine temperature rises during summer and other times.

When heating is used in winter, etc., the heater cock 8 is switched to communicate with the heater core 4 side as shown in the first figure.

Then, the coolant that has cooled the engine 1 flows from the coolant passage 9a through the passage 4a to the heater core 4, where heat is exchanged and the cooled coolant flows into the passage 4.
From b, it passes through 9c and 9d into the thermostat case 10, is sucked into the pump 3 from 9e, and is supplied to the engine 1.

In this case, the thermostat 5 is activated by the temperature of the coolant, which is actively exchanged heat in the heater core 4 and whose temperature is significantly lowered (about 6° C.).

As mentioned above, when the coolant temperature in the heater core 4 reaches the set temperature, the thermostat valve 5 opens. The temperature is higher than the temperature of the coolant in the engine when the thermostat valve is opened by the temperature drop caused by the heater core 4, which can significantly improve heating performance.

In addition, one valve body 5c of the thermostat valve 5
When the thermostat valve 5 is closed, the influence of the temperature of the coolant in the engine 1 on the inside of the thermostat case 10 is completely cut off, and the thermostat valve 5 is operated only by the temperature of the low-temperature coolant that has passed through the heater core 4. It has the function of operating.

FIG. 3 shows a specific example of the switching structure using the heater pot 8 shown in FIG. 1. By rotating the heater pot 8 by 90 degrees from the illustrated heating use state, the passages 9b and 9c are brought into communication and the heating non-use state is established. The functions and effects are the first.
It is exactly the same as the one shown in the figure.

As described above, according to the present invention, the thermostat valve provided in the coolant circulation path from the coolant outlet of the engine to the radiator is connected to the engine side opening of the thermostat case in which the thermostat valve is installed and to the circulation path. The structure has two valve bodies that open and close both the roadside opening and the roadside opening integrally, and a temperature-sensing section is installed between the two valve bodies, and the temperature-sensing section is installed after the engine has cooled down. By configuring the system so that the coolant or the coolant that has been heat exchanged with the heater core after engine cooling flows through the thermostat, the thermostat is not affected by the coolant temperature in the engine or the coolant temperature in the circulation path, etc., and the heating is stopped. When in use, only the temperature of the coolant that cooled the engine is used.
When heating is in use, it operates only with the temperature of the engine coolant that has been heat exchanged in the heater core of the heating system, and in summer, when heating is not in use, it keeps the engine coolant temperature relatively low and prevents various problems caused by rising engine temperatures. In addition, it is possible to significantly improve the heating effect by keeping the temperature of the engine coolant at a high level when heating is used in winter, etc., and can bring about a great practical effect.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of the route of the engine coolant showing an embodiment of the present invention, FIG. 2 is a sectional view showing a specific example of the thermostat valve section of FIG. 1, and FIG. 3 is a diagram of the heater cock section of FIG. 1. FIG. 7 is an explanatory diagram showing another specific example. 1...Engine, 2...Radiator, 3...Pump,
4... Heater core, 5... Thermostat valve,
6, 7...Cooling liquid circulation valve, 8...Heater cock,
9... Coolant passage, 10... Thermostat case.

Claims (1)

[Claims] 1 An engine coolant circulation path that supplies the coolant after cooling the engine from the engine coolant outlet through the radiator to the engine coolant inlet, and a coolant outlet provided upstream of the engine coolant outlet. When the coolant after cooling the engine is used for heating, a coolant passage is provided in which the coolant is passed through the heater core of the heating device and then delivered to the coolant inlet of the engine when the coolant is used for heating. In a device equipped with a thermostat valve that controls opening and closing, the thermostat valve is installed in a thermostat case interposed between the engine coolant outlet and the engine coolant circulation path, and the thermostat is The engine is configured to have two valve bodies that simultaneously open and close the engine side opening and the circulation path side opening of the tat case, and a temperature sensing part is located between the two valve bodies, and the coolant flows through the coolant passage. The coolant after cooling or the coolant after heat exchange in the heater core after cooling the engine flows through the thermostat case between the two valve bodies and is supplied to the coolant inlet of the engine. A control device for an engine cooling system characterized by: