JPH0117633Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention relates to a seal structure at a portion where a cylinder head cover is attached to a cylinder head.

[Prior art]

Conventionally, a cast product has generally been used as a cylinder head cover (hereinafter simply referred to as a cover), and the structure for mounting it on the cylinder head is to open vertically downward along the outer edge of the cover 1d as shown in Fig. 9. A groove 13d is formed, and an elastic sealing member 2f having a substantially rectangular cross section and a height slightly higher than the depth of the groove 13d as shown in FIG.
There was a type in which the two were tightened and fixed in opposite directions with bolts.

By the way, press-formed covers have recently come to be used due to demands for lighter covers and lower costs. When forming the above-mentioned groove in this cover, the inner circumferential wall of the sheet metal is fixed to the inside of the outer edge of the container-shaped cover body made of sheet metal by means such as welding, and the groove is formed between the outer circumference of the main body and the inner circumferential wall. However, the problem is that the groove width tends to become uneven during processing and welding, resulting in poor sealing performance, and the sealing member is removed from the groove during assembly to the cylinder head. There were problems such as the parts falling off. Therefore, as shown in FIG. 11, a sealing member 2h is sometimes used in which protrusions 25 are formed at multiple locations on the outer circumferential surface and the inner circumferential surface to prevent the sealing member from falling off, but the sealing member surface partially protrudes. Therefore, there was a problem that the sealing performance further deteriorated.

[Problem that this invention attempts to solve]

This idea was made in view of the above circumstances.
In a seal structure in which a groove is formed along the outer edge of the cylinder head cover, an elastic seal member is press-fitted into the groove in advance, and the cover is pressed into contact with the cylinder head via the seal member, the width of the groove may vary slightly. It is an object of the present invention to provide a seal structure that can be attached to a groove with good sealing performance without the risk of a seal member falling off even if the seal member falls off.

[Means to solve the problem]

The seal structure of the present invention has an annular groove that opens downward and has a U-shaped cross section along the outer edge of the cylinder head cover. The present invention is characterized in that an annular elastic sealing member having a shape of 100 mm is press-fitted therein, and the cylinder head cover is brought into pressure contact with the cylinder head through this sealing member.

[Function and effect]

Since the cross-sectional shape of the sealing member as a whole is inclined with respect to the cross-sectional shape of the groove of the cover, when the sealing member is press-fitted into the groove of the cover, one circumferential surface of the sealing member is formed at its upper part, and the other circumferential surface is The lower portion of the circumferential surface comes into particularly strong pressure contact with the wall surface of the groove, resulting in good sealing performance and the sealing member will not fall out of the groove during the work of attaching the cover to the cylinder head.

〔Example〕

Hereinafter, the present invention will be explained with reference to illustrated embodiments.

Figures 1, 2, and 3 each show a cross section of the outer periphery of the cover used in the present invention.
Both covers are made of pressed sheet metal.
Each of the cover members 1a, 1b, and 1c has a container-shaped main body 11 whose outer periphery is bent downward into an L-shape, and one side of a sheet metal 12 bent into an L-shape is attached to the lower surface of the outer periphery. A groove 1 with a substantially U-shaped cross section that is welded and opens downward over the entire circumference between a bent end 111 forming an outer peripheral wall and a bent end 121 forming an inner peripheral wall.
3a, 13b, and 13c are formed. however,
The groove 13a is a parallelogram in which the inner and outer peripheral walls 111 and 121 are inclined outward, and the groove 13b is a parallelogram with the inner and outer peripheral walls 11
1 and 121 are parallelograms inclined inward, and the groove 13c forms a cross-sectional space in which the inner and outer walls 111 and 121 are both vertically rectangular.

Next, FIGS. 4 to 8 show cross-sectional shapes of seal members made of elastic materials such as rubber and resin used in the seal structure of the present invention. The shape of the seal member is thus selected depending on the shape of the groove in the cover.
That is, the seal members 2a, 2b, 2c shown in FIGS. 4, 5, and 6 are used in the grooves 13a, 13b of the cover member shown in FIGS. 1 and 2. The sealing member 2a has a rectangular cross section, and its outer peripheral surface and inner peripheral surface are inclined relative to the inner peripheral wall 121 and the outer peripheral wall 111 of the grooves 13a and 13b. The seal member 2b as a whole has a shape slightly inclined in the direction of inclination of the groove 13a.
It is inclined relative to a. Seal member 2
c has a structure in which a flange 21 is formed at the bottom of the seal member 2a. Each seal member 2a, 2
The thickness of the groove insertion portions b and 2c is the same as or slightly larger than the groove width. When the seal member 2a is applied to the groove 13a, when the rectangular seal member 2a is pushed into the parallelogram groove 13a, the seal member 2a is forcibly deformed into a parallelogram. There are forces working to restore it. As a result, in the groove 13a, the upper part P ₁ of the outer peripheral wall 111 and the inner peripheral wall 121
The sealing member 2a is pressed particularly strongly at the lower part _P2 of. Therefore, the sealing member 2a is strongly held within the groove 13a by this pressing force, and does not fall off from the groove 13a during the cover attachment operation, and the sealing performance is improved by the pressing force. The sealing members 2b and 2c shown in FIG. 5 and FIG.
3a and 13b, in the same way as above, when the seal member is press-fitted into the groove, either the upper or lower part of the outer circumferential wall 111 or the inner circumferential wall 121 comes into strong pressure contact with the seal member due to the shape restoring force. The same effects as above are achieved. Note that the seal member 2c
A flange portion 21 is formed at the lower part of the cover, thereby improving the adhesion with the bottom surfaces of the inner and outer peripheral walls 111 and 121 of the cover.

Next, regarding the cover 1c shown in FIG. 3, for example, a seal member 2 having the cross-sectional shape shown in FIGS. 7 and 8.
d, 2e are applied. All of these are square quadrilaterals, and when they are press-fitted into the groove 13c of the cover 1c, they are forced to deform into a rectangle, and the shape restoring force causes the outer peripheral wall 1
11, a strong pressing force acts on the upper or lower part of the inner circumferential wall 121, producing the same effect as described above.

As explained above, the present invention provides a groove on the outer periphery of the cylinder head cover, press-fits a sealing member having a vertical inclination angle different from the wall surface of the groove into the groove, and tightens and fixes the cylinder head cover to the cylinder head. This seal structure improves the retention of the seal member in the groove and the sealing performance between the cover and the cylinder head when the cover is attached to the cylinder head.

[Brief explanation of drawings]

Figures 1 to 3 are cross-sectional views showing the structure of the outer peripheral edge of the cylinder head cover used in the present invention, and Figures 4 to 6 apply to the cylinder head cover shown in Figures 1 and 2. 7 and 8 are cross-sectional views of a seal member applied to the cylinder head cover shown in FIG. 3, and FIG. 9 is a cross-sectional view showing the structure of the outer peripheral edge of a conventional cylinder head cover. , FIG. 10, and FIG. 11 are sectional views of a sealing member applied to a conventional cylinder cover. 1a, 1b, 1c, 1d...Cylinder head cover, 111...Outer peripheral wall, 121...Inner peripheral wall, 1
3a, 13b, 13c, 13d... groove, 2a, 2
b, 2c, 2d, 2e, 2f, 2h...Sealing members.

Claims (1)

[Scope of utility model registration request] An annular groove having a substantially U-shaped cross section and opening downward is formed between the outer circumferential wall and the inner circumferential wall formed along the outer edge of the cylinder head cover, and the outer circumferential surface and the inner circumferential surface are substantially parallel to each other in this groove, A sealing structure for a cylinder head cover, in which an annular elastic sealing member having an inclined surface with respect to a wall surface of a groove is press-fitted, and an outer edge of the cylinder head cover is press-fixed to a cylinder head via the sealing member.