JP2580298Y2 - Thermostat device for internal combustion engine - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermostat for an internal combustion engine, for example, for controlling the amount of engine cooling water flowing to a radiator.

[0002]

2. Description of the Related Art Conventionally, as a thermostat device for an internal combustion engine of the above-mentioned example, there is a device disclosed in Japanese Utility Model Laid-Open No. 59-186418, for example. That is, as shown in FIGS. 3 and 4, a thermostat cover 41 constituting a part of a cooling water passage, a valve seat 44 of a thermostat 43 attached between a thermostat case 42 and a wax case 45 are fitted. And a coil spring 47 for pressing the main valve 46 in the direction of the valve seat 44, and a supporting member 48 for supporting the lower end of the coil spring 47. And a tubular body 49 attached to a lower part of the wax case 45 described above.

[0003] The above-described bottom-bypass type thermostat device has an inlet port 5 of a thermostat cover 41.
0 is connected to a lower tank 53 of a radiator 52 via a radiator outlet hose 51, and an outlet port 54 of the thermostat case 42 is connected to a water channel 5.
5 is connected to the suction side of the water pump 56, and a discharge line 57 of the water pump 56 is connected to the engine 5
8 and a heater core 59 of a heating device. The return water from the water jacket is returned to the upper tank 62 of the radiator 52 via the return pipe 60 and the radiator inlet hose 61, and is returned from the heater core 59. The flowing water is returned to the outlet port 54 downstream via the return line 63, and the bypass passage 64 is connected to the bypass port 65 of the thermostat case 42 for use.

Here, a plurality of blades 66 for forming a swirling flow for guiding the bypass water flow toward the wax case 45 and an opening 67 are formed in the cylindrical body 49 so that the cylindrical body 49 has a cylindrical shape. The body 49 itself is a bypass valve B.

[0005] The above-described thermostat device for an internal combustion engine includes:
When the temperature of the engine cooling water is cold at a predetermined temperature (eg, 83 ° C.) or lower, the main valve 46 is closed and the bypass valve B is opened by the action of the wax as a temperature sensing agent in the wax case 45. Then, the engine cooling water is circulated as indicated by the arrow in FIG. 3, and when the temperature of the engine cooling water reaches a predetermined temperature, the main valve is moved through the needle 68 by the expansion action of the wax. The valve 46 is opened and the bypass valve B is closed to allow the engine cooling water to flow as shown by the arrow in FIG.

However, the above-mentioned conventional apparatus has the following problems. That is, since the coil spring 47 is supported by the support member 48, there is a problem that not only the number of parts is increased but also the number of assembly steps is increased. Also, due to the number of turns of the coil spring 47 described above,
The coil spring 47 itself acts as a resistance to the flow of the engine cooling water, and the urging force of the coil spring 47 acts only on the main valve 46 and does not act on the valve seat 44. If the engine cooling water leaks from the inlet port 50 of the thermostat cover 41 to the outlet port 54 of the thermostat case 42 in the cold state shown in FIG. There is a problem that the heating effect cannot be obtained because the hot water is not circulated in 59.

In addition, the wax case 45 undesirably pivots around the needle 68 and the lower cylinder 49 pivots, thereby reliably guiding the bypass water flow to the wax case 45. This is relatively difficult, and there is a problem that good temperature-sensitive characteristics are impaired.

[0008]

According to the first aspect of the present invention, an existing pipe for forming a bypass passage is provided.
Protrude and fix the inside of the Mostat case.
Water flow control means that guides the Ipass water flow to the wax case side
By forming, the wax case may rotate undesirably
However, the above-mentioned water flow control means can control the bypass water flow.
Can reliably guide budge possible to Kkusukesu side, good temperature sensitive
It is an object of the present invention to provide a thermostat device for an internal combustion engine that can secure characteristics .

The invention according to claim 2 of the present invention combines the object of the invention according to claim 1 with the object of the coil spring.
By directly supporting the other end with a thermostat case
And reduce the number of parts and assembly man-hours.
While increasing the length of coil spring
And the engine cooling water by the coil spring itself
Reduces flow resistance and biases coil springs
By biasing the force on both the main valve and the valve seat,
Significant sealing performance of the valve seat arrangement when the main valve is closed
It is an object of the present invention to provide a thermostat device for an internal combustion engine that can be improved .

[0010]

The invention according to claim 1 of the present invention is directed to a thermostat that faces a wax case.
A pipe for forming a bypass passage is fitted to a predetermined portion of the base,
Protrude the inner end of the pipe into the thermostat case.
And a bypass water flow is supplied to the protruding portion on the wax case side.
Forming water flow control means leading to the water flow
An opening and closing member for opening and closing the projection of the pipe including the means,
A thermostat device for an internal combustion engine having a bypass valve attached to the wax case .

According to a second aspect of the present invention, a cooling water is provided.
A thermostat cover that forms part of the passage, and a thermostat
Of the thermostat mounted between the stat case
The valve seat is fitted to the wax case and comes into contact with and separates from the valve seat.
A main valve and a pusher for urging the main valve in the valve seat direction.
Thermostat device for an internal combustion engine with an il spring
And the other end of the coil spring is connected to the thermostat.
Directly supported by a stat case, and paired with the above wax case
A bypass passage is formed in a predetermined part of the thermostat case facing
Fitting the pipe, and connect the inner end of the pipe to the thermopile.
Protruding into the stat case, bypass water flow
To the wax case side.
And a projection of the pipe including the water flow control means.
The closing member that opens and closes and is attached to the wax case
With a thermostat device for an internal combustion engine with a bypass valve
There is a feature.

[0012]

According to the first aspect of the present invention, the bypass passage is fixed to the thermostat case.
Existing pipe to be protruded into the thermostat case
Then, the bypass water flow is sent to the wax case
Since the water flow control means is formed,
Even if the source rotates undesirably, the water flow control means
Water flow to the wax case side,
There is an effect that good temperature sensitivity characteristics can be secured.

According to the invention described in claim 3 of the invention,
With the configuration as described above, the effect of the invention according to claim 1 is obtained.
At the same time, a coil spring that presses and biases the main valve at one end
The other end of the ring was directly supported by the thermostat case.
This eliminates the need for conventional support members, and as a result, the number of parts
The effect of reducing the number of assembly steps
is there.

In addition, the above-mentioned coil spring is placed under the main valve.
Relatively long space between the section and the thermostat case
The coil spring can be arranged
The length can be increased and the number of turns can be set
In the case of a
Is wider, the engine by the coil spring itself
This has the effect of reducing the flow resistance of the cooling water.
You.

When the main valve is closed, the above-described coil
Spring bias acts on both main valve and valve seat
As a result, the sealing property of the valve seat
Can be greatly improved, preventing overcooling.
For example, heating equipment can be installed in the cooling water system of the engine.
Good heating effect when a heater core is installed
Can be obtained.

[0016]

An embodiment of the present invention will be described in detail below with reference to the drawings. The drawing shows a thermostat device of the internal combustion engine,
1 and 2, a thermostat cover 1 and a thermostat case 2 which constitute a part of a cooling water passage are provided, and an annular concave portion is formed on an inner peripheral surface of a joining end of the thermostat cover 1 to the thermostat case 2. A groove 3 is formed, and an annular rubber gasket 4 is interposed in the concave groove 3 to fasten the thermostat cover 1 and the thermostat case 2 described above.

The rubber gasket 4 has a flange portion at the valve seat 6 of the thermostat 5 mounted thereon, and a needle 8 is fixed to the center of the valve seat 6 via a stopper 7. The needle 8 is formed by the action (volume change) of the wax as a temperature sensing agent contained in the wax case 9.
It is driven in and out of the wax case 9.

A main valve 10 which comes into contact with and separates from the valve seat 6 is fitted into the wax case 9 and the main valve 10 and the spring seat 2 of the thermostat case 2 are fitted.
A coil spring 11 that presses and biases the above-described main valve 10 in the direction of the valve seat 6 is stretched between the coil spring 11 and the valve spring a.

Further, an opening 2b is formed in a predetermined portion of the thermostat case 2 facing the above-mentioned wax case 9, and a pipe 1 for forming a bypass passage is formed in the opening 2b.
2 is press-fitted, and the inner end of the pipe 12 is protruded inward from the thermostat case 2.

In the above-mentioned protruding portion, a notch 13 is formed as a water flow control means for guiding the bypass water flow to the wax case 9 side, and the above-mentioned protruding portion of the pipe 12 including this notch 13 is formed. A bypass valve 15 is formed by attaching a tubular body 14 as an opening / closing member for opening and closing the lower part of the wax case 9 described above.

In the thermostat device 16 of the bottom bypass type constructed as described above, the above-described inlet port 17 of the thermostat cover 1 is connected to the lower tank 20 of the radiator 19 via the radiator outlet hose 18, and the outlet of the thermostat case 2 is connected. The port 21 is connected to the suction side of the water pump 23 via the water passage 22, and the discharge line 2 of the water pump 23
4 is connected to the water jacket inside the engine 25 and the heater core 26 of the heating device, and the circulating water from the water jacket is supplied to the radiator 1 via the return pipe 27 and the radiator inlet hose 28.
9 to return to the upper tank 29, return water from the heater core 26 to return to the outlet port 21 downstream through the return line 30, and connect the bypass passage 31 (specifically, a hose) to the above. For use.

The illustrated embodiment is constructed as described above, and the operation will be described below. When the temperature of the engine cooling water is cold (cold) at or below a predetermined temperature (for example, 83 ° C.), the amount of protrusion of the needle 8 becomes small due to the action of the wax in the wax case 9 as shown in FIG. The main valve 10 is actuated by the coil spring 11 so that the valve seat 6
And the cylindrical body 14 below the wax case 9 opens the notch 13 and opens the bypass valve 15. As a result, the engine cooling water discharged by the water pump 23 is supplied to the radiator 1 as shown by the arrow in FIG.
Circulate bypassing 9.

On the other hand, when the temperature of the engine cooling water reaches a predetermined temperature, the wax in the work case 9 expands due to a volume change as shown in FIG. Thus, the main valve 10 is in an open state separated from the valve seat 6, the cylinder 14 below the wax case 9 closes the cutout 13, and closes the bypass valve 15. As a result, the engine cooling water discharged by the water pump 23 is supplied to the radiator 1 as shown by an arrow in FIG.
Circulate via 9

Since the lower end of the coil spring 11 is directly supported by the thermostat case 2, a support member having a conventional structure is not required. As a result, the number of parts and the number of assembling steps are reduced. There is an effect that can be.

Further, since the above-described coil spring 11 can be disposed in a relatively long space between the lower portion of the main valve 10 and the inner surface of the thermostat case 2, the disposition length of the coil spring 11 can be increased. When the number of windings is set to be the same as that of the related art, the winding interval of the coil spring 11, that is, the pitch is widened, and there is an effect that the flow resistance of the engine cooling water by the coil spring 11 itself can be reduced.

When the main valve 10 is closed, the urging force of the coil spring 11 is applied to the main valve 10 and the valve seat 6.
Therefore, when the main valve 10 is closed, the sealing performance of the portion where the valve seat 6 is disposed can be significantly improved, and there is an effect that overcooling can be prevented. When the heater core 26 for the heating device is provided in the cooling water system 25, a good heating effect can be obtained.

In addition, an existing pipe 12 fixed to the above-mentioned thermostat case 2 and forming a bypass passage is protruded into the thermostat case 2, and the bypass water flow is guided to the wax case 9 side by this protruding portion. Since the notch 13 as the flowing water flow control means is formed, even if the wax case 9 rotates undesirably, the above-described notch 13 can surely guide the bypass water flow to the wax case 9 side. Thus, there is an effect that good temperature sensitivity characteristics can be secured.

In correspondence between the configuration of the present invention and the above-described embodiment, the water flow control means of the present invention corresponds to the notch 13 of the embodiment, and similarly, the opening / closing member corresponds to the cylindrical body 14. However, the present invention is not limited to the configuration of the above-described embodiment. For example, in the above embodiment, the outer periphery of the protruding portion of the pipe 12 is configured to be opened and closed by the cylindrical body 14. However, the inner periphery of the protruding portion of the pipe 12 may be configured to be opened and closed by the cylindrical body 14. The means may be another structure that cuts and raises the water flow control piece in the pipe 12.

[Brief description of the drawings]

FIG. 1 is a system diagram of a thermostat device of an internal combustion engine of the present invention in a cold state.

FIG. 2 is a system diagram of the thermostat device of the internal combustion engine of the present invention in a warm state.

FIG. 3 is a system diagram of a conventional thermostat device for an internal combustion engine when it is cold.

FIG. 4 is a system diagram of a conventional thermostat device of an internal combustion engine at the time of warming.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Thermostat cover 2 ... Thermostat case 5 ... Thermostat 6 ... Valve seat 9 ... Work case 10 ... Main valve 11 ... Coil spring 12 ... Pipe 13 ... Notch part 14 ... Cylindrical body 15 ... Bypass valve

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Naoki Hayashi 3-1, Shinchi, Fuchu-cho, Aki-gun, Hiroshima Mazda Co., Ltd. (56) References JP-A-59-23028 (JP, A) −45270 (JP, U)

Claims (2)

(57) [Scope of request for utility model registration] 1. A thermostat opposed to a wax case.
Fits a pipe for forming a bypass passage into a predetermined part of the case
And project the inner end of the pipe into the thermostat case.
And guide the bypass water flow to the wax case side at the projecting portion.
Forming water flow control means, and opening and closing the projection of the pipe including the water flow control means.
Attach the opening / closing member to the above wax case and install the bypass valve
A thermostat device for an internal combustion engine comprising: 2. A thermostat forming a part of a cooling water passage.
Between the thermostat cover and the thermostat case.
Thermostat valve seat and wax case
A main valve that comes into contact with or separates from the valve seat, and
Internal combustion engine provided with a coil spring that urges in a direction
Thermostat device, wherein the other end of the coil spring is connected to the thermostat cable.
Of the thermostat case , which is directly supported by
A pipe for forming a bypass passage is fitted into a predetermined portion, and the inner end of the pipe projects into the thermostat case.
And guide the bypass water flow to the wax case side at the projecting portion.
Forming water flow control means, and opening and closing the projection of the pipe including the water flow control means.
Attach the opening / closing member to the above wax case and install the bypass valve
A thermostat device for an internal combustion engine comprising: