JPH0524864Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a cylinder head gasket for an internal combustion engine, and more particularly to a metal gasket having a bead in the sealing portion.

[Conventional technology]

A conventional metal cylinder head gasket for an internal combustion engine is made of at least one thin metal plate having an annular bead (wavy protrusion) in the sealing area around the bore of the cylinder head gasket. In addition, a plating layer or a thermal spray layer is provided around the bore hole in order to improve the sealing performance of the engine bore and improve the fatigue strength of the bore bead provided in an annular shape around the bore. Figures 4 and 5
An example of this is shown in FIG.

FIG. 3 shows a plan view of a cylinder head gasket 1 for a general four-cylinder internal combustion engine.

As shown in FIG. 3, the cylinder head gasket 1 is provided with a head bolt hole 2, a water hole 3, an oil hole 4, and a bore hole 5. A bore bead 6 having a wavy cross section is provided around the bore hole 5 in an annular shape.

Figures 4, 5, and 6 show the conventional example as shown in Figure 3A-
It is shown in section A.

FIG. 4 shows a cylinder head gasket made of a single thin metal plate, on which a bore bead 6 is formed using the thin metal plate as a seal plate 7. On this seal plate 7, the circumference between the bore bead 6 and the bore hole 5 is formed. The portion 8 is provided with a plating layer or a sprayed layer 9. Furthermore, a thin rubber film or a rubbery paint film 10 is coated on the surfaces of the seal plate 7 and the plating layer or sprayed material layer 9 in order to improve the sealing performance of the cylinder head gasket 1.

FIGS. 5 and 6 show an example of a cylinder head gasket made of three thin metal plates.
12 and a core plate 13 in the center. As in the case of FIG. 4, a plating layer or a sprayed layer 9 is provided on the circumferential portion 8 between the bore bead 6 and the bore hole 5, and this coats both or one of the upper and lower seal plates 11 and 12. It is installed on one side or on the core plate 13. FIG. 5 shows an example in which the plating layer or sprayed layer 9 is provided on the core plate 13, and FIG. 6 shows an example in which the upper sealing plate 11 is provided.

[Problem that the invention attempts to solve]

In addition to the method of providing the above-mentioned plating layer or thermal spray layer on the seal plate or core plate, it is difficult to maintain the accuracy of their thickness and position, and these processing methods are expensive. Furthermore, since the equipment required for this purpose is large-scale, it is not an industrially effective method.

[Means for solving problems]

In order to solve the above problems, in the present invention, in a metal cylinder head gasket with a bead in the sealing part, a thin metal is inserted between the bore hole of the thin metal plate forming the cylinder head gasket and the bore bead. Provided is a cylinder head gasket for an internal combustion engine in which a reinforcing plate is adhesively fixed to the metal thin plate via a rubber thin film.

[Effect]

The initial load around the bore of the cylinder head or cylinder block of the engine is applied to the layer formed by the adhesively fixed thin metal reinforcing plate between the bore hole and the bore bead, and therefore, during engine operation. The minute displacement between the cylinder head and the engine block is reduced, the stress amplitude applied to the bore bead is reduced, the bore bead is less susceptible to fatigue failure, and its fatigue strength is improved.

〔Example〕

An embodiment of the present invention will be described based on FIGS. 1 to 3. 1 and 2 each show an embodiment of the present invention taken along the line A--A in FIG. 3.

FIG. 1 shows a first embodiment of the present invention, which is a cylinder head gasket made of one thin metal plate, which corresponds to the conventional example shown in FIG. 4. A bore bead 6 is formed on the single thin metal plate as a seal plate 7, and a thin rubber film or a thin rubber paint film 10 is applied to the surface of the seal plate 7 to improve the sealing performance of the cylinder head gasket 1. A thin metal reinforcing plate 20 is adhesively fixed to the circumferential portion 8 between the bore bead 6 and the bore hole 5 by utilizing the adhesiveness of the thin film 10. At this time, it may be fixed by hot current adhesion. In this case, the rubber thin film etc. 10 is further added to the metal reinforcing plate 2.
It may be coated on the upper side of 0.

FIG. 2 shows a second embodiment of the present invention, showing a cylinder head gasket made of three thin metal plates,
This corresponds to the conventional example shown in FIGS. 5 and 6. Cylinder head gasket 1 according to this embodiment
The upper and lower two seal plates 11 and 12 on which the bore bead 6 is formed, and the two seal plates 11 and 1
This is a three-layer metal gasket consisting of a central core plate 13 sandwiched between two gaskets 2, and a thin rubber film or a thin rubber paint film 14 is adhered to both upper and lower surfaces of the core plate 13. The thin rubber film 14 may be applied to only one side of the core plate 13 or to the surfaces of the seal plates 11 and 12, depending on the situation. Further, in the circumferential portion 8 between the bore bead 6 and the bore hole 5, a thin metal reinforcing plate 20 is placed on top of the rubber thin film 14 attached to the upper surface of the core plate 13. It is fixed with adhesive using its properties. At this time, hot-flow bonding may be performed after fixing to the rubber thin film.

With the above configuration, according to this embodiment, for the layer formed by the thin metal reinforcing plate 20,
By applying the initial load around the bore,
The minute displacement between the cylinder head and the engine block during engine operation is reduced, the stress amplitude applied to the bore bead is reduced, and the fatigue strength of the bore bead is increased.

[Effect of idea]

By implementing the present invention, the following effects can be obtained.

(1) As mentioned above, since the thin metal reinforcing plate is fixed using the adhesive properties of a thin rubber film, the processing method is extremely easy, and it is extremely inexpensive without making any major changes to the conventional process. can be produced.

(2) It is easier to maintain accuracy in thickness and position compared to the case where a conventional plating layer or thermal spray layer is provided.

[Brief explanation of drawings]

FIG. 1 is a sectional view of the first embodiment of the present invention taken along the line AA in FIG. 3, FIG. 2 is a sectional view of the second embodiment of the invention taken along the line AA in FIG. Figure 3 is a plan view of the cylinder head gasket, Figures 4 and 5.
6 are sectional views taken along the line AA in FIG. 3, respectively, of conventional examples of cylinder head gaskets. DESCRIPTION OF SYMBOLS 1... Cylinder head gasket, 5... Bore hole, 6... Bore bead, 7, 11, 12... Seal plate, 8... Circumferential portion, 9... Plating layer or sprayed material layer, 10, 14... ...Rubber thin film, 13... Core plate, 20... Metal reinforcing plate.

Claims (1)

[Claims for Utility Model Registration] In a metal cylinder head gasket having a bead in the sealing part, a thin metal reinforcing plate made of rubber is inserted between the bore hole of the thin metal plate forming the cylinder head gasket and the bore bead. A cylinder head gasket for an internal combustion engine, characterized in that it is adhesively fixed to the thin metal plate using the adhesive force of the thin film.