JPS5817270A - Thermostat for car internal combustion engine - Google Patents

Abstract

PURPOSE:To lower the valve opening preset temperature at a high load region, to raise it at a low load region, and to suppress the overheat by controlling the position of a valve seat in response to operating conditions by means of an oil pressure applied to a rubber tube. CONSTITUTION:At a high load region of an engine, a solenoid valve 19 is actuated by means of an intake negative pressure sensor 20 to apply an oil pressure to a rubber tube 18. Thereby, a gap 10A between the tip of a shaft 10 and an elastic rubber 9 is eliminated and the spring force of a spring 12 is reduced, then, as a pellet 8 starts melting a valve 6 immediately starts moving downward, that is, the valve opening temperature is lowered. On the other hand, at a low load region of the engine, the oil pressure is not applied to the rubber tube 18, therefore, a valve seat 7 is kept in contact with a housing 15, and even if the pellet 8 starts melting the valve 6 does not immediately move downward, that is, the valve opening temperature is raised.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an internal combustion engine for an automobile (hereinafter referred to as an engine).
) Regarding the thermostat, in the cooling system for an internal combustion engine for an automobile, as shown in Figure 1, a cooling liquid is circulated outside the high temperature parts of the cylinder and cylinder head of the internal combustion engine 1. . Connect the coolant outlet of the water jacket to the radiator 3 via the thermostat, and forcibly circulate the coolant using the water pump 4 installed at the coolant inlet. It is cooled down.

As shown in FIG. 2, the conventional Su-Mostat 2 has a pulp 6 integrally formed with a pellet container 6 and a valve seat 1 facing the pulp 6, and the inside of the pellet container is kept at a constant temperature. Enclose melting wax pellets S. The valve seat 7 is formed integrally with the valve seat 10 and the nermostat body 11, which are inserted by fitting an elastic rubber into the bellet 16i. , when the pellets 8 are not melted, the pulp 6 is brought into contact with the valve seat 7. As described above, this thermostat 2 is installed midway through the coolant outlet passage from the water jacket of the engine to the radiator 3. That is, the seven flange 13 integrally formed with the thermostat body 11 is clamped and fixed between flanges provided at the joints of the thermostat housing cap 14 and the thermostat housing 15.

When the coolant temperature rises and reaches a certain temperature, the wax pellets 8 in the pellet container 5 begin to bathe and expand in volume, compressing the elastic rubber 9 and forcing the shaft 10 upward.

Now, the upper end of the shaft 10 is fixed, and the bowl 5 and the pulp 6 are relatively displaced downward to open the pulp 6.

In such a conventional thermostat 2, the temperature setting is constant while the valve is open, and the opening area of the pulp 6 increases in proportion to the rise in coolant temperature.
If the valve opening temperature is set high in consideration of the low load range, cooling will not be sufficient in the high load range, causing overheating.If the valve opening temperature is set low in the low load range, the engine will Even when the engine is cooling, the valve opens to allow proper cooling, increasing cooling loss and increasing fuel consumption.

The purpose of the present invention is to eliminate the above-mentioned drawbacks, change the valve opening temperature of the thermostat depending on the operating condition of the machine/engine, and
In the high load range, the valve opening temperature is set to low (and in the low load range, it is set to high).
K provides a thermostat for an automobile internal combustion engine that controls settings.

Hereinafter, the present invention will be described in detail with reference to 1Oiii. In addition, similar parts in the conventional example shown in FIG. 2 and the embodiment shown in FIG. .

FIG. S shows an embodiment of the present invention, and shows a thermostat housing 11#)? - A recess 1sm is formed at the joint with the mostat housing cap 14, into which the flange 13 of the valve seat 7 is fitted vertically movably.
The pulp 6 is brought into contact with the spring 17 provided between the 1t-b fitted to the 0 and the receiver 1@. Valve seat 7
The lower surface of the flange portion 13 of the thermostat housing 1
A hollow rubber tube 18 as a valve moving means is inserted between the bottom surface of the concave portion 15A and the bottom surface of the concave portion 15A.

The hollow rubber tube 18 is communicated with an engine oil gear (not shown) via a solenoid valve 19, and when the solenoid valve 19 is opened, engine oil flows into the hollow part of the rubber tube 18, causing hydraulic pressure. 5 is in effect. A negative pressure sensor 20 operates according to the load, and detects engine suction negative pressure to operate the electromagnetic valve 19.

Further, as described above, the pulp 6 is formed integrally with the pellet container 5 in which the wax pellets 8 are enclosed, and the spring 1 is provided between the pulp 6 and the thermostat housing 15! The pulp 6 is brought into contact with the valve seat 7 to cut off the coolant.

Further, the shaft IOK elastic rubber 9 whose one end is fixed to the thermostat housing cap 14 is fitted and inserted into the pellet container 5. Here, as will be described later, in order to change the positional relationship between the shaft 10 and the pellet container 5 depending on the load condition of the engine, a gap of 10 mm is provided between the tip of the shirt 10 and the elastic rubber 9. I'll keep it. 21 is 1.
This is an O-ring.Next, the operation of the thermostat configured in this way will be explained. In the negative range of the engine, as shown in diagram wI4, is the suction negative pressure sensor? 20 by solenoid valve 19
is activated to apply hydraulic pressure to the rubber tube 18. That is, in a high load range, the suction negative pressure is small, in other words, it approaches atmospheric pressure, which opens the solenoid valve 19 (and guides the engine oil to the rubber tube 18. Therefore, the rubber tube 18 expands, and the valve seat 107 lunge 1s
It rises until it comes into contact with the thermostat housing cap 14.

As a result, the threshold 110mm between the tip of the shaft 7) 19 and the elastic rubber 9 is eliminated, and the spring force of the spring 12 is also smaller than in the case of the 8th m, so that the pellet
As soon as the pulp 6 begins to melt, the pulp 6 begins to move downward. That is, the valve opening temperature becomes lower.

On the other hand, in the low load range of the engine, as shown in FIG. A gap of 10 mm is created between the elastic rubber 9 and the spring l! The spring force of is increased, so that even if the pellets 8 start melting in the bath, the pulp 6 does not immediately move downward.

-Increased arrogance.

In this way, the valve opening set temperature can be controlled by moving the position of the valve seat 7 by turning off the hydraulic pressure acting on the rubber tube 1-. That is, the valve opening temperature of the thermostat is the same as that of a thermostat having a pellet capacity of 5M, a valve 6, pellets 89 and elastic rubber 9, and a shaft 10.
tk is determined by the relative position between the shaft 1G and the thermostat, and the closer the relative positions of the shaft 1G and the thermostat are, the lower the valve-opening set temperature becomes, and conversely, the more they are apart, the higher it becomes.

As explained above, in the present invention, the driving condition! According to lK [
By controlling the position of the pulp sear F with hydraulic pressure acting on the rubber tube, the valve opening temperature can be kept low in high load areas.
The valve opening temperature setting was set higher in the low load range, so
It is possible to control the optimum coolant temperature in a high load range, and it is possible to suppress overheating. In addition, in the low load range, the reduction in cooling loss reduces fuel consumption by r! Ki can be done.

Furthermore, since the valve opening temperature is high during idling, engine performance is improved, and the liquid temperature during warm-up is higher than before, and the wall temperature is also higher (which reduces the amount of carbon and hydrogen in the exhaust gas).

[Brief explanation of drawings]

The gx diagram is a configuration diagram showing an example of a cooling position for an internal combustion engine, and the second diagram is a cross-sectional diagram showing an example of a conventional thermostat.
Figures 3 to 4 are sectional views of two embodiments of the thermostat of the present invention. 1- internal combustion engine, 2- thermostat, 3...
Radiator, 4--Water pump, 5--Pellet container, 6--Pulp, 7-Papsy F1
B.-wax pellet, 9-elastic rubber, 1
0...Shaft, 10mm gap, 11...Thermostat body, 12--Spring, 13...
7 lange, 14... thermostat housing cap, 15-- thermostat housing, 15A-- recess, 16... spring receiver, 1
7... Spring, is... Hollow rubber tube (pulp moving means) 19... Solenoid valve, 20... Negative pressure sensor, 21... 0 ring. Patent applicant Nichii Motor Co., Ltd.

Claims (1)

[Scope of Claims] l) A pellet container filled with wax pellets that are heated to a predetermined temperature of a coolant for cooling an internal combustion engine, and a pulp formed integrally with the wrinkled pellet container, one end of which is fixed and the other end of which is fixed. The shaft inserted into the pellet capacity 11jIK, the valve seat still in contact with the pulp and blocking the cooling liquid, #
A thermostat for an internal combustion engine for an automobile, comprising a pulp moving means for moving a valve seat together with the pulp relative to the shaft. 2) A thermostat for an internal combustion engine for an automobile, characterized in that the valve seat moving means is driven in accordance with the load condition of the internal combustion engine in the thermostat according to the patent-required item 5m1t.