JPS621154B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a temperature-sensitive valve, and more particularly to a temperature-sensitive valve that is incorporated into an engine cooling system to control the flow of cooling water.

The cooling system of an engine generally includes a water jacket formed in an engine housing such as a cylinder block or a cylinder head, a water pump connected to the water jacket on the discharge side, a radiator, and the water jacket. an inlet passage that leads the cooling water of the bucket to the radiator; an outlet passage that leads the cooling water of the radiator to the suction side of the water pump; and an outlet passage that branches off from the middle of the inlet passage and connects the water pump to the water pump. and a temperature-sensitive valve for controlling the flow of cooling water at a branching portion between the inlet passage and the bypass passage or a branching portion between the outlet passage and the bypass passage. ing.

The temperature-sensitive valve is often a thermowax-type temperature-sensitive valve, which prevents the coolant from flowing to the radiator until the temperature of the coolant flowing through the water jacket reaches a predetermined value, and directs the coolant to a bypass passage. On the other hand, when the temperature of the cooling water reaches a predetermined value, the cooling water is allowed to flow toward the radiator. In this case, the temperature sensing part of the temperature sensing valve, that is, the thermowax element, is not affected by the temperature of the cooling water on the radiator side until the temperature of the cooling water reaches a predetermined value, and the cooling water flows through the bypass passage. It is necessary to operate in response to only the temperature of . Otherwise, the thermowax element of the temperature-sensitive valve will be affected by the temperature of the cold cooling water on the radiator side, and even if the temperature of the cooling water flowing through the water jacket reaches a predetermined value, the temperature-sensing valve will not operate and the radiator will Cooling water will not flow to the engine, which may cause the engine to overheat. This is especially noticeable in winter when the temperature is low in cold regions and the temperature of the cooling water on the radiator side is low.

However, in many temperature-sensitive valves commonly used in the past, an annular valve element is attached directly to the end of the thermowax element, and the end of the thermowax element is attached to the radiator side. Since the port is closed, the cooling water from the radiator comes into direct contact with a part of the thermowax element, and the thermowax element is relatively influenced by the temperature of the cooling water from the radiator. .

If the temperature of the cooling water on the radiator side is constant,
The operating temperature of the temperature-sensitive valve can be set by taking into account the temperature of the cooling water, but since the temperature of the cooling water on the radiator side changes depending on changes in the air temperature, etc. Variations in operating temperature occur. For this reason, in practice, it has been necessary to set the operating temperature of the temperature-sensitive valve to a somewhat low value in order to prevent engine overheating, even at the expense of promoting warm-up of the engine.

In view of the above-mentioned drawbacks of conventional temperature-sensitive valves, the present invention provides a thermowax element that is substantially unaffected by the cooling water on the radiator side.
It is an object of the present invention to provide an improved temperature-sensitive valve that operates reliably in response to the temperature of a desired fluid.

Such an object, according to the invention, provides a valve housing having a first inlet port for conducting a first fluid, a second inlet port for conducting a second fluid, and an outlet port; a first valve element that opens and closes the port; a second valve element that opens and closes the second inlet port; and a thermowax element that is disposed within the valve housing and drives the first and second valve elements. The first valve element is driven in the valve opening direction as the temperature sensed by the thermowax element increases, and the second valve element is driven to close as the temperature sensed by the thermowax element increases. actuated in a valving direction, the thermowax element being substantially thermally isolated from the first fluid when the first inlet port is closed by the first valve element; This is accomplished by a temperature sensitive valve, such as one configured to only contact fluid.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to the accompanying drawings.

The attached FIG. 1 is a schematic diagram showing the engine cooling system. In the figure, reference numeral 1 indicates an engine housing consisting of a cylinder block, a cylinder head, etc., and a water jacket 2 is installed inside the engine housing.
is provided. The engine housing 1 is provided with a water pump 3 driven by a crankshaft (not shown), and this water pump 3 is connected to the water jacket 2 at its discharge side, and is connected to the water jacket 2 to supply water. Cooling water is supplied into the jacket 2. The water jacket 2 has a cooling water outlet 4 at its upper part, and this cooling water outlet 4 is connected to a cooling water inlet 7 provided at the upper part of the radiator 6 via an inlet passage 5. The water jacket 2 also has a cooling water outlet 8 at its lower part, and this cooling water outlet 8 is connected to an outlet passage 9.
It is connected to the suction side of the water pump 3 via the temperature-sensitive valve 10 and the outlet passage 9b.
Further, one end of a bypass passage 11 is connected to the middle of the inlet passage 5, and the other end of this bypass passage 11 is connected to the temperature-sensitive valve 10.

FIG. 2 is a longitudinal sectional view showing one embodiment of the temperature-sensitive valve 10 according to the present invention. The temperature-sensitive valve 10 has a cylindrical valve housing 12 that is open at both ends, and the valve housing 12 has a first inlet port 13 connected at one end to one end of the inlet passage 9b.
and an outlet port 14 connected at the other end to one end of the inlet passage 9b.
The valve housing 12 defines an annular chamber 15 between its side peripheral wall and a pipe wall defining the inlet passage 9a, and this chamber 15 is connected to the bypass passage 11 on one side. , on the other hand, are connected to a plurality of second inlet ports 16 opened in the side circumferential wall of the valve housing 12 . Said room 1
5 is fluid-tightly shut off from the inlet passage 9a by an O-ring 17 at one end, and connected to the outlet passage 9b by a flange 18 provided at the other end of the valve housing 12 at the other end. It is shut off in a more liquid-tight state. The first inlet port 13 is opened and closed by a disc-shaped first valve element 19, and the second inlet port 16 is opened and closed by an annular second valve element 20. There is.

A thermowax element 21 is provided within the valve housing 12. The thermowax element 21 includes a piston guide member 22 and a metal cylindrical casing 23 with a bottom that surrounds the piston guide member 22. The piston guide member 22 has a rubber piston 25 in its guide hole 24. , a synthetic resin plate 26, and a needle 27 are supported movably in the axial direction thereof. A thermally expandable substance 28 such as wax is sealed in a sealed chamber provided between the piston guide member 22 and the casing 23. The thermowax element 21 is connected to the first valve element 1 via a cylindrical stay member 29 at the bottom of its casing 23.
9, and is also connected to the second valve element 20 at the stepped portion of the casing 23, and further engages a bridge member 32 whose both ends are connected to the flange portion 18 at the tip of the needle 27. There is. still,
A heat insulating material 33 is provided at the joint between the casing 23 and the stay member 29. The stay member 29 is also provided with a hole 30 so that cooling water can enter the inner cylindrical portion thereof. Further, between the second valve element 20 and the stepped portion of the valve housing 12, the second valve element 20 is biased in the valve opening direction and the first valve element 19 is biased in the valve closing direction. A conical coil spring 31 is provided.

In the state shown in FIG. 2, the temperature of the cooling water around the thermowax element 22 is low and the thermally expandable material 28 of the thermowax element 21 is contracted. the inlet port 13 is fully closed by the first valve element 19;
The state when the second inlet port 16 is fully open is shown. In this state, the valve housing 1
Cooling water is supplied to the chamber 15 from the bypass passage 11 in the chamber 2.
Entering via second inlet port 16 and exit port 1
4 to the outlet passage 9b. Therefore,
At this time, the bypass passage 11 is connected to the inlet passage 9 all around the thermowax element 21.
The thermowax element 21 is filled with cooling water heading toward b, and the thermowax element 21 is connected from the bypass passage 11 to the outlet passage 9 on substantially the entire outer peripheral surface thereof.
contact with the cooling water heading towards b, and the thermally expandable material 2
8 is heated by the cooling water and expands as the temperature of the cooling water increases. When the thermally expandable material 28 of the thermowax element 21 expands as the temperature of the cooling water rises, the rubber piston 2
5. The piston guide member 22 and the casing 23 move to the left in FIG. 2 against the action of the conical coil spring 31 relative to the synthetic resin plate 26 and the needle 27, and the first valve element 19 opens. While driving in the valve direction, the second valve element 20 is also driven in the valve closing direction.
At this time, the second valve element 20 is
The piston guide member 2 cooperates with the inner circumferential surface of the piston guide member 2.
2 and the casing 23 are guided for movement. When the first valve element 19 moves in the valve opening direction and the first inlet port 13 is opened, the cooling water in the radiator 6 flows into the valve housing 12 from the first inlet port 13 via the inlet passage 9a. The coolant flows along with the cooling water from the bypass passage 11 through the outlet port 14 toward the inlet passage 9b. Therefore,
After the first valve element 19 is opened, the thermowax element 21 is brought into contact with the cooling water from the first inlet port 13 and the cooling water from the second inlet port 16, and the thermowax element 21 comes into contact with the cooling water from the first inlet port 13 and the second inlet port 16. The wax element 21 operates in response to the average temperature of both cooling waters. When the second inlet port 16 is substantially completely closed by the second valve element 20, only cooling water via the radiator 6 flows into the valve housing 12, and the thermowax element 21 is closed. It operates in response to the temperature of the cooling water.

As described above, according to the temperature-sensitive valve according to the present invention, when the first inlet port is closed by the first valve element, the thermowax element is substantially more heat transferable than the cooling water on the radiator side. Since it is isolated and comes into contact only with the cooling water flowing through the bypass passage, the thermowax element is not affected by the temperature of the cooling water on the radiator side in such a state, and the temperature of the cooling water flowing through the bypass passage does not change. It will only react and operate. Therefore,
The temperature-sensitive valve operates reliably according to the temperature of the cooling water in the water jacket, regardless of changes in the air temperature.

[Brief explanation of the drawing]

Figure 1 is a schematic configuration diagram showing the engine cooling system.
FIG. 2 is a longitudinal cross-sectional view showing one embodiment of the temperature-sensitive valve according to the present invention. 1-Engine housing, 2-Water jacket, 3-Water pump, 4-Cooling water outlet, 5
- inlet passage, 6 - radiator, 7 - cooling water inlet, 8 - cooling water outlet, 9a, 9b - outlet passage, 10 - temperature sensitive valve, 11 - bypass passage, 1
2-valve housing, 13-first inlet port, 1
4-Outlet port, 15-Chamber, 16-Second inlet port, 17-O ring, 18-Flange portion, 19
- first valve element, 20 - second valve element, 21 - thermowax element, 22 - piston guide member, 23 - casing, 24 - guide hole, 25
~ rubber piston, 26 ~ synthetic resin plate, 27 ~ needle, 28 ~ thermally expandable material, 29 ~ stay member,
30-hole, 31-conical coil spring, 32-bridge member, 33-insulating material.

Claims (1)

[Claims] 1 A valve housing having a first inlet port for introducing a first fluid, a second inlet port for introducing a second fluid, and an outlet port, and a first valve element for opening and closing the first inlet port. a second valve element for opening and closing the second inlet port; and a thermowax element disposed within the valve housing for driving the first and second valve elements; The second valve element is driven in the valve-opening direction as the temperature sensed by the thermowax element increases, and the second valve element is driven in the valve-closing direction as the temperature sensed by the thermowax element increases. The Tux element is configured to be substantially thermally isolated from the first fluid and in contact only with the second fluid when the first inlet port is closed by the first valve element. A temperature-sensitive valve characterized by: