JPH0138287Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a laminated cylinder head gasket.

(Prior Art) Conventionally, as an example is shown in FIG. 1, a cylinder head gasket 3 interposed between a cylinder body 1 and a cylinder head 2 is partially shown in a plan view in FIG. As shown in the cross-sectional view taken along the line in FIG. 2, the gasket is of a laminated type, and the portion that abuts the upper end of the cylinder liner 4 (see FIG. 1) is formed as a bore grommet 5. The portion other than the water hole grommet 6, oil hole grommet 7, and push rod hole grommet 8 is defined as a non-sealed portion 9.

Further, a lower plate 10, a middle plate 11, an upper plate 12, and a bead plate 1 provided between the lower plate 10 and the middle plate 11.
3, 14, etc., and the middle plate 11 is 11A,
It is a combination of two pieces of 11B.

(Problem to be solved by the invention) Such a conventional stacked cylinder head gasket 3 has a bead 1 under the bore grommet 5.
3A and 13B are formed, but no bead is formed in the non-sealed part 9, and the middle plate 11 is formed as 11A, 13B.
Due to the structure of the two plates 11B and the thickness accuracy of the middle plates 11A and 11B, it is inevitable that a small gap (0.05 to 0.1 mm) will be created between the upper plate 12 and the middle plate 11. I was getting used to it. Therefore, when fixing the cylinder head 2 with a stud bolt (not shown) on the cylinder body side inserted into the bolt hole 16, a surface pressure difference occurs between the bore grommet 5 and the non-sealed part 9, and the axial force of the bolt Even if the design allows the non-sealed portion to share the required percentage of This causes the upper plate 12 to vibrate in the vertical direction, a so-called "knocking" phenomenon, which impairs the gas sealing function and also causes a reduction in the service life of the gasket.

(Means for Solving the Problems) Based on the above-mentioned viewpoint, the present invention provides a gasket for a cylinder head that makes it possible to ensure surface pressure in the non-sealed part, and has a bore grommet and a non-sealed part. In this gasket for a cylinder head, which has a laminated structure consisting of a bead plate, a middle plate, an upper plate, etc., arc-shaped beads are protruded from the middle plate in the non-sealed part in an intermittent arrangement concentrically with the bore grommet.

(Function) By protruding a large number of arc-shaped beads with relatively low rigidity in an intermittent arrangement concentrically with the bore grommet over the entire middle plate in the non-sealed part, the connection between the upper plate and the middle plate is improved in the arc-shaped bead portion. To eliminate minute gaps and to equalize the surface pressure between a bore grommet part and a non-sealed part as much as possible without pressing the upper plate strongly and deforming it.

(Example) An example of the present invention will be described in detail with reference to the drawings.

It is a plan view with a part cut out from Fig. 4, and also Fig. 5.
Each figure shows an embodiment of the gasket of the present invention in an enlarged sectional view along the line in FIG. 4.

The gasket 17 of the present invention has a first appearance shape.
Although it is the same as the conventional gasket 3 shown in Figures 3 to 3, the cross-sectional structure is as shown in Figure 5.
Bead plates 13, 14, middle plate 18, and upper plate 12
A large number of arcuate beads 19 are protruded from the intermediate plate 18 in the non-sealed portion 9 in an intermittent arrangement concentrically with the bore grommet 5.

Here, if the arc-shaped bead 19 is strong, it will lose its function as the non-sealing part 9, so the thickness of the middle plate 18 should be set to about 0.1 to 0.15 mm, or the
As shown in the enlarged cross-sectional view in the figure, the arcuate bead 19
A slit 20 is provided at the top of the bead 19 so that the rigidity is relatively low.
The height (0.05~
0.1mm).

Since the gasket 17 of the present invention has the above structure, even if there is a slight difference in the tightening force when attaching the cylinder head 2 to the cylinder body 1 as shown in FIG. The minute gap between the plate 12 and the middle plate 11 no longer exists, and by making the arc bead 19 concentric with the bore grommet 5 and having relatively low rigidity, the non-sealed part 9 is prevented from coming into contact with the upper plate 12. By minimizing the pressure area and minimizing the pressing force on the top plate 12, the top plate 12 is not pressed too hard and deformed, and the arc-shaped beads 19 are arranged intermittently. The seal portion 9 is evenly pressed over the entire area, and the entire surface pressure becomes equal.

(Effects of the invention) As is clear from the above explanation, the gasket of the invention can be interposed between the cylinder body and cylinder head with uniform surface pressure, does not cause deformation, and maintains a reliable gas seal for a long period of time. It has an excellent advantage that it can be maintained for a long time.

[Brief explanation of the drawing]

Fig. 1 is a partial longitudinal cross-sectional view showing an example of the use of a cylinder head gasket, Fig. 2 is a plan view showing a part of a conventional gasket, Fig. 3 is an enlarged sectional view of the portion lined in Fig. 2, and Fig. 4 The figure is a plan view showing a part of the gasket of the present invention, FIG. 5 is an enlarged sectional view of the portion taken along the line in FIG. DESCRIPTION OF SYMBOLS 1... Cylinder body, 2... Cylinder head, 3... Conventional gasket, 4... Cylinder liner, 5... Bore grommet, 9... Non-sealing part, 17... Gasket of the present invention, 18... Book Middle plate of devised gasket, 19... Arc-shaped bead, 20...
...Slit.

Claims (1)

[Scope of utility model registration request] In a cylinder head gasket that has a bore grommet and a non-sealing part and has a laminated structure consisting of a bead plate, a middle plate, and an upper plate, the middle plate in the non-sealing part has an arc shape concentrically arranged intermittently with the bore grommet. A cylinder head gasket with a protruding bead.