JPH0118826Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention relates to a cylinder head gasket that is used by being interposed between the cylinder head and cylinder block of an engine.

[Prior Art] This type of gasket has a plate-shaped gasket body with cylinder bores, bolt holes, and various passage holes for circulating fluids such as cooling water, lubricating oil, blow-by gas, etc. This is commonly used by being inserted between the cylinder head and cylinder block of an engine in a tightened state.

[Problems to be solved by the invention] However, if the cylinder bore and various holes are simply drilled in a plate-shaped gasket body,
Because it is difficult to partially strengthen the sealing function,
For example, there is an inconvenience in that cooling water, lubricating oil, blow-by gas, etc. are likely to leak to the outside through the sealing surface from passage holes located relatively close to the outer periphery of the gasket body.

The primary purpose of the present invention is to eliminate such inconveniences, but as shown in Japanese Utility Model Publication No. 12513/1983 as a prior art, it has been found that Some have large transparent windows in the . This product can increase the sealing surface pressure at the periphery of the passage hole, etc. without significantly increasing the tightening force against the gasket. However, with such a structure, the tightening force acts intensively on parts other than the transparent window, so the gasket body may lose its elasticity in a short period of time. There is an inconvenience that it gets old.
Further, in such a structure, a large number of through holes are formed in the gasket body in addition to the essential passage holes, so that the rigidity of the gasket body is significantly reduced. Therefore, there is a high possibility of damage due to incorrect handling during assembly. Also,
If the rigidity of the gasket body is low, it may deform unduly when tightened, and it is often not possible to obtain the expected sealing performance. The present invention aims to solve the above problems.

[Means for solving the problem] In order to achieve the above purpose, the present invention
The following configuration is adopted.

The gasket of this invention has a plate-shaped gasket body formed by bonding a surface plate to both sides of a core plate, and has passage holes for circulating fluid such as water, oil, or blow-by gas. An elongated sealing groove along the opening edge of the passage hole is provided only in a portion of both surface plates of the gasket body located between the passage hole and an outer peripheral edge of the gasket body relatively close to the passage hole. It is characterized by

[Function] With such a configuration, a so-called labyrinth effect will be exhibited at the seal groove forming portions on both surface plates of the gasket body, so that the passage hole provided in the gasket body and the passage hole will be It is possible to partially strengthen the sealing performance between the outer circumferential edge of the adjacent gasket body.

Furthermore, this gasket has a three-layer structure in which face plates are bonded to both sides of a core material, and seal grooves are formed only on both of the face plates. Therefore, the rigidity of the gasket main body can be maintained relatively high, and handling becomes easy. The surface plate with the seal groove is adhered to the core material without the seal groove and is held in such a way that it cannot be displaced, so even if the gasket body is squeezed, the seal groove portion may It is unlikely to cause deformation. Therefore, it is possible to reliably exhibit the expected sealing performance.

[Example] Hereinafter, an example of the present invention will be described with reference to the drawings.

A gasket 1 according to the present invention is used interposed between a cylinder block 2 and a cylinder head 3 of an engine, and is mainly composed of a thin plate-shaped gasket body 4. The gasket body 4 is, for example, made by bonding surface plates 6, 6 made of flexible material to both sides of a core plate 5, and has cylinder bores 7, bolt holes (not shown), and various passage holes at required locations. 8, 9... are drilled. In addition,
A passage hole 8 formed on one side edge of the gasket body 4 is for circulating lubricating oil and blow-by gas, and is penetrated from one sealing surface 4a to the other sealing surface 4b. In addition, the passage hole 9 bored on the other side edge side of the gasket body 4...
It is for circulating cooling water, and similarly penetrates from one sealing surface 4a to the other sealing surface 4b.

Both surface plates 6 of this gasket body 4,
Seal grooves 11 and 12 are provided at portions located between the passage hole 8 at 6 and the outer peripheral edges 4c and 4d of the gasket body 4 relatively close to the passage hole 8, respectively. The seal grooves 11 and 12 are elongated (5 mm or less in width) extending along the opening edge of the passage hole 8, and are located between the seal groove 11 formed on the seal surface 4a of one surface plate 6 and the seal groove 11 formed on the seal surface 4a of one surface plate 6. The sealing groove 12 formed on the sealing surface 4b is separated from the sealing groove 12 by the core material 5. That is, the seal groove 11 is provided only on the surface plates 6, 6, and the seal groove 11 is provided only on the surface plates 6, 6, and
It is not provided. Also, the passage holes 9 in both the surface plates 6, 6 and the outer peripheral edge 4e of the gasket body 4 relatively close to the passage holes 9...
A seal groove 13..., 14 is located between the
... are provided for each. Seal groove 13...,
14... have the same structure as the seal grooves 11..., 12..., and are formed in a curved shape along the opening edge of the passage hole 9....

With such a configuration, the seal grooves 11, 1 in the surface plates 6, 6 of the gasket body 4
Since the so-called labyrinth effect is exhibited at the portions where gaskets 2, 13, and 14 are formed, the passage holes 8, 9, and so on provided in the gasket body 4,
9. Outer peripheral edge 4 of gasket body 4 adjacent to...
It becomes possible to partially strengthen the sealing performance between the parts c, 4d, and 4e. Therefore, lubricating oil, blow-by gas, cooling water, etc. flowing through the passage holes 8, 9, etc. are guided to the outer peripheral edges 4c, 4d, 4e through the seal surfaces 4a, 4b, and the outer peripheral edges 4c, The inconvenience of leakage from 4d and 4e to the outside can be effectively suppressed.

Moreover, the seal grooves 11, 12, 13, 14
The seal grooves 11, 12, 1 are elongated and are provided only in areas where seals are required.
3 and 14, there is no problem in that the surface pressure acting on the sealing surfaces 4a, 4b of the gasket body 4 increases unduly. Therefore, the desired sealing performance can be maintained over a long period of time without causing the problem that the gasket body 4 loses its elasticity within a short period of time.

Moreover, this gasket body 4 has a three-layer structure in which surface plates 6, 6 are bonded to both surfaces of a core material 5, and seal grooves 11, 12, 13, 14 are formed only on both surface plates 6, 6. ing. Therefore, the rigidity of the gasket body 4 can be maintained relatively high, and handling becomes easy. Therefore, it is possible to effectively prevent damage caused by incorrect handling during assembly. A surface plate 6 having seal grooves 11, 12, 13, 14,
6 is bonded to the core material 5 which does not have a seal groove and is held in such a way that it cannot be misaligned.
Even if this gasket body 4 is compressed, the seal groove 1
There is a low possibility that portions 1, 12, 13, and 14 will undergo unexpected deformation. Therefore, it is possible to reliably exhibit the expected sealing performance.

In the above embodiment, one seal groove is provided between the outer peripheral edge of the gasket body and each passage hole, but a plurality of parallel seal grooves may be provided, for example.

[Effects of the invention] As explained above, the present invention has a simple structure in which a long and narrow sealing groove (for example, a groove with a width of about 1 mm to 5 mm) is provided only in a limited part of the surface plate of the gasket body. The present invention provides a gasket for a cylinder head that can effectively suppress the inconvenience that fluids such as water, oil, or blow-by gas flowing through various passage holes leak to the outside through a sealing surface over a long period of time. be.

Moreover, the seal groove is only formed on the surface plate bonded to both sides of the core material.
It is possible to maintain the rigidity of the gasket body, effectively preventing problems such as damage due to incorrect handling, and preventing unexpected deformation when tightened and used. It is possible to obtain the effect that the sealing performance can be reliably exhibited.

[Brief explanation of the drawing]

Figure 1 is a plan view showing one embodiment of the present invention;
The figure is an enlarged sectional view taken along the - line in FIG. 1. 1... Gasket, 4... Gasket body, 4
a, 4b... Seal surface, 4c, 4d, 4e... Outer periphery, 5... Core material, 6... Surface plate, 8, 9...
Passage hole, 11, 12, 13, 14...Seal groove.

Claims (1)

[Scope of utility model registration request] In a gasket formed by having passage holes for circulating a fluid such as water, oil, or blow-by gas in a plate-shaped gasket body formed by bonding face plates to both sides of a core plate, both face plates of the gasket body A cylinder characterized in that an elongated sealing groove along the opening edge of the passage hole is provided only in a portion located between the passage hole and the outer peripheral edge of the gasket body relatively close to the passage hole. Head gasket.