JPH0614123Y2 - gasket - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a gasket mounted between a cylinder head and a head cover of an automobile engine, for example.

[Prior Art] Conventionally, as a gasket mounted between a cylinder head and a head cover of an automobile engine, there is a gasket shown in FIG. This gasket 21 is used for the head cover 2
The fitting portion 24 fitted into the housing groove 23 formed in the lower end surface of the second member 2 and the exposed portion 25 exposed downward from the housing groove 23.
And a head cover 22 with a bolt (not shown).
When the cylinder head 26 is fastened to the cylinder head 26, the exposed portion 25 is pressed against the joint surface 26 a of the cylinder head 26. In the gasket 21, the fitting portion 24 is fitted in the housing groove 23, and the exposed portion 25 is not pressed against the joint surface 26a.
The fitting direction length of the fitting portion 24 is set so that there is almost no gap between the inner bottom surface 23a and the fitting portion 24, and the exposed portion 25 is not pressed against the joint surface 26a. The thickness C of the exposed portion 25 is set to be larger than the width A of the opening edge of the accommodation groove 23.

When the gasket 21 configured as described above is used, the fitting portion 24 is fitted into the accommodation groove 23 of the head cover 22, and in this state, the exposed portion 25 of the gasket 21 together with the head cover 22 is attached to the joint surface 26 a of the cylinder head 26.
Place on top. Subsequently, the head cover 22 is pressed against the cylinder head 26 by tightening the bolt. Then, as shown in FIG. 5, the gasket 21 is deformed between the head cover 22 and the cylinder head 26 and comes into close contact with them, so that the gap between the inner surface of the housing groove 23 and the fitting portion 24, and the cylinder head 26. A seal is formed between the joint surface 26a and the exposed portion 25.

[Problems to be Solved by the Invention] Generally, it is difficult to accurately process the housing groove 23 of the head cover 22, and if the fitting portion 24 is simply fitted into the housing groove 23, a gap is created between them. You can't stick it like you don't. Also, gasket 2
If 1 is used for a long period of time, it may deteriorate due to heat from the engine and the sealing performance may deteriorate. Therefore, conventionally, from the viewpoint of reliably sealing the inner surface of the accommodation groove 23 and the fitting portion 24 and anticipating a decrease in sealing performance due to heat deterioration, the head cover 22 is applied to the cylinder head 26 with a large force. It is tightening.

However, when the head cover 22 is tightened with a large force as described above, the exposed portion 25 is crushed as shown in FIG. 5, and both sides of the exposed portion 25 protrude into the gap between the cylinder head 26 and the head cover 22. Therefore, a part of the tightening force is used for tightening the protruding portion, and there is a problem that the sealing property is deteriorated accordingly.

The purpose of the present invention is, when mounted between a pair of joined bodies,
An object of the present invention is to provide a gasket that has a small exposed portion between both bonded bodies and can exhibit a high sealing property even with a small pressing force.

[Means for Solving the Problems] Therefore, in order to achieve the above-mentioned object, the present invention relates to a fitting portion to be fitted into an expanded housing groove of an opening formed in one joined body, and the fitting portion. And the exposed portion exposed from the accommodation groove when the fitting portion is fitted into the accommodation groove, and the one joined body is inserted into the accommodation portion. In the state, by pressing to the joint surface side of the other joint body, by pressing the exposed portion to the joint surface,
In a gasket that seals between the fitting portion and the inner surface of the housing groove and between the exposed portion and the joint surface, the exposed portion of the fitting portion corresponds to the expanded opening of the housing groove. The fitting portion has a length that is continuous in the fitting direction, and that the fitting portion has a length in the fitting direction such that the inner bottom surface of the accommodation groove and the fitting portion are separated with a gap when the fitting portion is fitted. The gist of the gasket is that the thickness of the exposed portion is set smaller than the width of the opening edge of the accommodation groove when the fitting portion is fitted.

[Operation] When joining a pair of joined bodies, first, the fitting portion of the gasket is fitted into the accommodation groove of the one joined body. In this state, a gap is created between the inner bottom surface of the accommodation groove and the fitting portion.

Then, when the exposed portion of the gasket fitted in the housing groove is pressed against the joint surface of the other joined body, the gasket is deformed by the pressing force at this time, and part of the exposed portion goes into the gap between the joined bodies. I try to stick out. However, in the present invention, since a gap is formed between the inner bottom surface of the accommodation groove and the fitting portion, a part of the fitting portion enters the gap. Further, in the present invention, since the thickness of the exposed portion of the gasket is set to be smaller than the width of the opening edge of the housing groove, even if the gasket is deformed as described above, the exposed portion does not reach the gap between the two joined bodies. Most do not stick out.

[Embodiment] An embodiment embodying the present invention will be described below with reference to FIGS.

As shown in FIGS. 1 and 2, the gasket 1 of the present embodiment is made of rubber such as nitrile rubber in a generally square ring shape, and has an engine head cover 3 as one joined body and the other one. It is mounted between the cylinder head 2 as a bonded body and seals the two. An accommodating groove 4 that opens at the lower end surface of the head cover 3 is formed in a substantially rectangular ring shape corresponding to the shape of the gasket 1. A pair of inclined surfaces 5 is formed on both sides of the lower portion of the accommodation groove 4 so as to widen toward the opening edge. In this embodiment, the width A between the lower edges of both inclined surfaces 5 is set to about 5.5 mm.

The gasket 1 is a fitting portion 6 fitted in the accommodation groove 4.
And an exposed portion 7 exposed downward from the housing groove 4, a seal lip 7a is formed on the lower surface of the exposed portion 7,
The entire lower surface of the exposed portion 7 including the seal lip 7a is brought into pressure contact with the joint surface 2a at the upper end of the cylinder head 2. The length of the fitting portion 6 in the fitting direction is
A gap G is formed between the inner bottom surface 4a of the accommodation groove 4 and the fitting portion 6 in a state where the fitting portion 6 is fitted in the accommodation groove 4 and the exposed portion 7 is not in pressure contact with the cylinder head 2. The length is set to occur. Further, the thickness C of the exposed portion 7 is set to be smaller than the width A between the lower end edges of the inclined surfaces 5 in a state where the exposed portion 7 is not pressed against the joint surface 2a of the cylinder head 2. In this embodiment, the vertical length B of the gap G is set to about 1 mm and the thickness C is set to about 4.5 mm.

In order to use the gasket of this embodiment constructed as described above, first, as shown in FIG.
Fit inside. At this time, a gap G is formed between the inner bottom surface 4a of the accommodation groove 4 and the upper end of the fitting portion 6.

Then, the seal lip 7 a of the exposed portion 7 of the gasket 1 fitted in the housing groove 4 is attached to the joint surface 2 a of the cylinder head 2.
Then, the head cover 3 is fastened to the cylinder head 2 with a bolt (not shown). Then, as shown in FIG. 3, the sealing lip 7 of the exposed portion 7 is tightened at this time.
a is pressed against the joint surface 2a. Furthermore, the head cover 3
When tightened, the entire gasket 1 is deformed and the exposed part 7
The entire lower surface of the above is pressed against the joint surface 2a of the cylinder head 2, and as a result, the exposed portion 7 and the joint surface 2a are sealed.

At this time, the exposed portion 7 is compressed in the vertical direction, so that both sides of the exposed portion 7 tend to protrude into the gap between the cylinder head 2 and the head cover 3. However, in this embodiment, the gap G is formed in the inner bottom portion of the accommodation groove 4, and the two inclined surfaces 5 formed on both lower sides of the accommodation groove 4 are press-fitted into the accommodation groove 4 with the fitting portion 6. Thus, a part of the gasket 1 deformed as described above enters the gap G. Further, in this embodiment, the thickness C of the exposed portion 7 is set to be smaller than the width A between the lower end edges of both inclined surfaces 5, so that even if the exposed portion 7 is compressed and deformed, the space between the cylinder head 2 and the head cover 3 is reduced. Almost does not protrude into the gap. Therefore, only a small amount of the tightening force is used to tighten the protruding portion.

As described above, when a part of the gasket 1 enters the gap G at the inner bottom portion of the housing groove 4 and is pressed against the inner surface of the housing groove 4, the inner surface of the housing groove 4 and the gasket 1 are separated from each other. Will be sealed.

As described above, according to the gasket 1 of this embodiment, when the inner surface of the housing groove 4 and the fitting portion 6 and the exposed portion 7 and the joint surface 2a are sealed, the cylinder head 2 and the head cover are sealed. There is almost no protrusion of the exposed part 7 between 3
High sealing performance can be achieved even with a small tightening force.

The present invention is not limited to the configuration of the above embodiment,
For example, the seal lip 7a of the exposed portion 7 may be omitted, the one inclined surface 5 of the housing groove 4 may be omitted, and the like, and any modifications may be made without departing from the spirit of the invention.

[Effects of the Invention] As described in detail above, according to the gasket of the present invention, the length of the fitting portion in the fitting direction is separated from the inner bottom surface of the accommodation groove with a gap when the fitting portion is fitted into the accommodation groove. Therefore, a wide space is provided between the fitting portion and the bottom surface of the accommodation groove to allow press fitting of the fitting portion when the exposed portion is pressed against the joint surface. A portion of the mating portion that is continuous to the exposed portion side is guided in the press-fitting direction by the expanded opening portion of the accommodation groove, and the thickness of the exposed portion when the fitting portion is fitted is larger than the opening edge width of the accommodation groove. Since it is set small, when pressing one bonded body to the bonding surface side of the other bonded body and sealing between the inner surface of the housing groove and the fitting part and between the exposed part and the bonding surface , There is little protrusion of the exposed part that is compressed and deformed between the pair of bonded bodies, and even with a small pressing force This has the effect of exhibiting high sealing performance.

[Brief description of drawings]

1 to 3 show an embodiment embodying the present invention.
The figure is a partial cross-sectional view showing a state where the fitting portion of the gasket is fitted into the accommodation groove, FIG. 2 is a perspective view showing the whole gasket, and FIG. 3 is a partial cross-sectional view showing a state where the exposed portion of the gasket is pressed against the joint surface. FIGS. 4 and 5 show the prior art, FIG. 4 is a partial cross-sectional view showing a state where the fitting portion of the gasket is fitted in the accommodation groove, and FIG. 5 is a state where the exposed portion of the gasket is pressed against the joint surface. FIG. 2 ... Cylinder head as other joined body, 2a ... Joining surface, 3 ... Head cover as one joined body, 4 ... Housing groove, 4a ... Inner bottom surface, 5 ... Inclined surface, 6 ... Fitting portion, 7 ... Exposed Part, A ... Width, C ... Thickness, G ... Gap.

Claims (1)

[Scope of utility model registration request] 1. A fitting part (6) fitted into a housing groove (4) having an expanded opening formed in one joined body (3), and the fitting part (6) being continuous with the fitting part (6). And an exposed portion (7) which is formed thicker than the fitting portion (6) and is exposed from the housing groove (4) when the fitting portion (6) is fitted in the housing groove (4). One joined body (3) is pressed toward the joining surface (2a) side of the other joined body (2) when the fitting portion (6) is fitted, and the exposed portion (7) is joined to the joining surface (2a). By press contacting with the fitting portion (6) and the inner surface of the housing groove (4),
And a gasket configured to seal between the exposed part (7) and the joint surface (2a), the exposed part of the fitting part (6) corresponding to the expanded opening of the accommodation groove (4). The joint is formed between the inner bottom surface (4a) of the accommodation groove (4) and the fitting portion (6) when the fitting portion (6) is in the fitted state while forming a continuous portion to the portion (7) side. The length of the fitting portion (6) in the fitting direction is set so that there is a gap (G) that allows the fitting portion (6) to be press-fitted when the exposed portion (7) is pressed against the surface (2a). , The thickness (C) of the exposed portion (7) when the fitting portion (6) is fitted, the width (A) of the opening edge of the housing groove (4)
Gasket characterized by being set smaller than