JPH0658423A - Cylinder head gasket - Google Patents

Abstract

PURPOSE:To make a cylinder head gasket conformable to the thermal deformation of a flange by forming a grommet, having an extension part covering a peripheral part of a coolant hole being situated at an outer boundary of a cylinder hole as one body, in a peripheral edge of this cylinder hole of a gasket body, in the gasket for an open deck type engine. CONSTITUTION:A cylinder head gasket consists of a gasket body 1 and a grommet 3 installed in the peripheral edge of a flange 2. An extension part 5 is solidly formed in this grommet 3 so as to cover a peripheral part of a coolant hole being situated at an outer boundary of this planger 2 as one body. This gasket body 1 is formed with a graphatic sheet material or the like while the grommet 3 is made of a metal sheet material respectively. This extension part is made up into plane form and extendedly installed up to a position going along the outer peripheral edge of a water groove of the engine.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an engine cylinder head gasket, and more particularly to an open deck type engine cylinder head gasket using a graphite sheet.

[0002]

2. Description of the Related Art In recent years, open-deck engines have become mainstream for downsizing and higher output of automobile engines, and cylinder head gaskets can also be prevented from being damaged by cooling water and the gasket thickness can be reduced. For the reason that it can be made thin and can withstand high internal pressure, metal gaskets that use a plurality of thin metal plates that have been subjected to bead processing on the peripheral edge of the hole have become the mainstream.

However, the metal gasket cannot easily follow the distortion between the flange surfaces when the flange surfaces (mainly the flange surface of the cylinder head) are thermally deformed due to long-term use of the engine, and gas leakage is likely to occur. there were.

[0004]

SUMMARY OF THE INVENTION The present invention provides a cylinder head gasket which can cope with thermal deformation of the flange surface due to long-term use of the engine.

The present invention also provides a cylinder head gasket which can be used as a cylinder head gasket for an open deck type engine by using a graphite sheet having a relatively poor water resistance.

[0006]

A cylinder head gasket according to the present invention comprises a gasket body having a planar shape corresponding to a flange surface to be applied, and a grommet provided around a cylinder hole of the gasket body. The grommet is formed substantially integrally with the grommet and includes an extension portion formed so as to cover a peripheral portion of the cooling water hole located on the outer periphery of the cylinder hole.

The cylinder head gasket according to the present invention can be applied as a cylinder head gasket for an open deck type engine by forming the gasket body from a graphite sheet material and disposing the extending portion on the cinder block side.

In the cylinder head gasket according to the present invention, the extended portion can be formed as the outer peripheral edge portion of the grommet, or can be formed as another metal thin plate member joined to the outer peripheral edge of the grommet.

[0009]

Since the portion of the gasket body located above the cooling water hole is covered with the extended portion of the grommet, the gasket body is prevented from swelling and being damaged by the cooling water.

As a result, a graphite sheet material having excellent water resistance, such as compression characteristics, heat resistance, chemical resistance, etc., while having relatively poor water resistance, is used as a cylinder head gasket for an open deck engine. It is possible to apply as, and corresponds to the large thermal deformation of the flange surface.

[0011]

EXAMPLE As shown in FIGS. 1 and 2, a cylinder head gasket according to an embodiment of the present invention is formed as a cylinder head gasket for an open deck type engine, and has a planar shape corresponding to an applied flange surface. The gasket body 1 has a grommet 3 provided on the periphery of the cylinder hole 2 of the gasket body 1.

The grommet 3 has an extension portion 5 formed so as to cover the peripheral portion of the cooling water hole 4 located on the outer periphery of the cylinder hole 2. The gasket body 1 is formed of a well-known gasket sheet material such as a graphite sheet material or an asbestos joint sheet material, and the grommet 3 is attached to the gasket body by a well-known means using a commonly used sheet metal material.

The planar shape of the extension portion 5 is formed so as to extend from the outer peripheral edge of the grommet 3 to a position along the outer peripheral edge of the water groove 6 of the open deck type engine, whereby the surface of the gasket body 1 is formed. Avoid swelling and peeling by the cooling water that is exposed above and flowing in the water channels 6.

The extended portions 5 may be provided on both sides of the gasket body 1, but it has been found that swelling and peeling due to cooling water mainly occur only on the cylinder block side of the engine. It is sufficient to provide it only on the cylinder block side. The distracted portion 5 can also be formed of a thin sheet metal material separate from the grommet 3, as shown in FIG.

The cylinder head gasket of the present invention constructed as described above is arranged so that the surface having the extended portion 5 is in contact with the flange surface of the cylinder block.
It is installed in the same way as a normal gasket.

[0016]

According to the present invention, since the gasket body 1 is protected from the cooling water flowing in the water groove 6 by the extended portion 5, it is possible to prevent the gasket body from swelling and peeling due to the cooling water. Thus, the gasket sheet material having a higher compression rate than that of the metal gasket can be applied to deal with the thermal deformation of the flange surface.

Furthermore, while having excellent characteristics as various gasket materials such as compression characteristics, heat resistance, and chemical resistance, a graphite sheet material having relatively poor water resistance is used as a cylinder head gasket for open deck type engines. It is applicable.

[Brief description of drawings]

FIG. 1 is a partial plan view showing a side of a cylinder head gasket that faces a cylinder block according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along line II-II in FIG.

FIG. 3 is a cross-sectional view of a cylinder head gasket according to an embodiment of the present invention, similar to FIG.

[Explanation of symbols]

 1 Gasket main body 2 Cylinder hole 3 Grommet 4 Cooling water hole 5 Extending part 6 Water groove

Claims (4)

[Claims] 1. A gasket main body having a planar shape corresponding to a flange surface to be applied, and a grommet provided at a peripheral edge of a cylinder hole of the gasket main body,
A cylinder head gasket, wherein the grommet is provided substantially with the grommet and has an extension portion that covers a peripheral portion of a cooling water hole located on the outer periphery of the cylinder hole. 2. The gasket body is a graphite sheet material, the applied flange surface is the flange surface formed between the cylinder block and the cylinder head of an open deck type engine, and the extended portion is on the cinder block side. The cylinder head gasket according to claim 1, wherein the cylinder head gasket is arranged. 3. The cylinder head gasket according to claim 1, wherein the extended portion is an outer peripheral edge portion of the grommet. 4. The extended portion is another thin metal plate member joined to the outer peripheral edge of the grommet.
Or the cylinder head gasket according to 2.