JPS6358306B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a metal gasket used as a flange gasket or a cylinder head gasket for an internal combustion engine.

Conventionally, it is attached to the joint surface of two relatively fixed members such as flange gaskets, cylinder head gaskets, etc., and prevents fluid from leaking between opposing holes provided in each of the two members. Most metal gaskets used asbestos as their main material. Most of the binders are synthetic rubbers, which are kneaded and then formed into a sheet to form a gasket. To explain such a conventional asbestos sheet gasket using drawings, Fig. 1 shows a gasket for a flange, and the sheet gasket 01 is formed by kneading asbestos as a main ingredient and synthetic rubber as a binder. is provided with a gasket hole 02 corresponding to the hole to be sealed in the flange member.

The periphery of the gasket hole 02 is covered with a thin metal grommet 03 for reinforcement.

Also, there are bolt holes 0 around the gasket 01.
4 is formed, and the two opposing flange members are fixed relative to each other by bolts passed through the bolt holes 04, and the gasket 01 is sandwiched between them and compressed. .
Figure 2 shows a cylinder head gasket for an internal combustion engine.This gasket 05 is made of a sheet material made of asbestos and synthetic rubber as a binder. It is formed by covering a thin metal plate 06. This gasket 05 has gasket holes 07 corresponding to the cylinder holes, and holes 0 corresponding to through holes for cooling water, lubricating oil, etc.
8, bolt holes 09 etc. are provided, holes 07,
There is also a thin metal grommet around the periphery of 08.
10 are coated. This gasket 05 is
It is compressed by being sandwiched between a cylinder and a cylinder head that are fixed to each other by bolts. Furthermore, Fig. 3 shows a cylinder head gasket similar to that shown in Fig. 2, but instead of covering a sheet member made of asbestos and synthetic rubber kneaded with a thin metal plate 06 as shown in Fig. 2. ,
A gasket 012 is shown in which a porous iron plate 011 is used as a core material and coated with a mixture of asbestos and synthetic rubber to form a sheet.

All of these conventional gaskets utilize their compressibility to provide a tight seal.
Asbestos is fibrous and has good compressibility, so it has been considered a suitable material for such gaskets. Furthermore, since asbestos has extremely high heat resistance, gaskets made of asbestos have been used in most cases where high-temperature fluids come into contact with gaskets.

However, asbestos is a limited underground resource, and it has become a problem that it has an adverse effect on the human body during the manufacturing process of its products. Furthermore, when asbestos products are used in automobiles, asbestos wear particles are dispersed into the air.
The problem has also arisen that it causes pollution.

In addition, in conventional asbestos gaskets, although asbestos itself, the main raw material, has high heat resistance, the synthetic rubber used as a binder deteriorates at about 150℃ at most, so its strength rapidly decreases in high temperature conditions. The drawback was that it deteriorated. For example, in the case of a cylinder head gasket, high temperature and high pressure gas acts on the gasket due to combustion and explosion of fuel within the cylinder. Therefore, a thin metal plate 06 as shown in FIG. 2 or a porous iron plate 011 as shown in FIG.
However, even in such a case, the strength of the peripheral edge portion of the hole 07 of the gasket 05, 012 was reduced, and gas spraying sometimes occurred. When trying to increase the scale by increasing the diameter of the cylinder hole, or when trying to make the internal combustion engine lighter and more compact, especially in the case of a multi-cylinder internal combustion engine, it is necessary to reduce the spacing between the cylinders. Therefore, the gas blow-through in this gasket part was an obstacle. Grommet 0 is added to further strengthen the peripheral part of hole 07.
Even if I try to increase the width of 10, the grommet is 0.
In order to prevent 10 comrades from overlapping,
I had my limits. Furthermore, if the distance between the cylinders is narrowed, extremely high temperatures of 230 to 250°C will be transmitted to the gasket, so the gasket itself must have good thermal conductivity.
Conventional asbestos gaskets also had the disadvantage that the synthetic rubber used as a binder lacked thermal conductivity. From the above, with conventional asbestos cylinder head gaskets,
It has been difficult to scale up internal combustion engines or make them lighter and more compact by increasing the diameter of the cylinder holes.

The present invention has been made in view of these points, and it is possible to provide a plurality of gasket holes close to each other while maintaining sufficient sealing performance. It is an object of the present invention to provide a metal gasket that can be made lightweight and compact, easy to manufacture, and extremely low in cost.

In order to achieve this object, the present invention uses a metal gasket in which a plurality of gasket holes are bored close to each other in the same plane, by blasting both surfaces of a soft metal plate to create a satin-like finish. The gasket hole is roughened in a shape, and a convex portion is formed on the peripheral edge of each gasket hole so as to be concentric in the vertical direction from both surfaces and overlap in shape at adjacent portions.

According to the present invention, a convex portion is formed on the peripheral edge of a plurality of gasket holes that are adjacent to each other in the same plane by making the metal plate concentric in the vertical direction from both surfaces and having an overlapping shape in the adjacent portions. , so even if the gasket holes are very close together,
The convex portion can completely seal the space between the two holes. Moreover, manufacturing is easy and costs are low.

Embodiments of the present invention will be described below with reference to FIGS. 4 to 7.

This embodiment shows a metal gasket applied to a cylinder head of a multi-cylinder internal combustion engine.

4 to 6 show an embodiment of the present invention. In FIG. 4, a metal gasket 1 has a plurality of gasket holes 2, 2 to be sealed, drilled in a soft metal plate such as aluminum in close proximity to each other with a small distance H between the two. Both surfaces of this metal gasket H are roughened into a satin-like texture by blasting or the like, and convex portions are formed on the peripheral edges 3 of both gasket holes 2, 2 concentrically in the vertical direction from both surfaces. 4, 4' are formed.

Furthermore, in this embodiment, FIGS. 4 and 6
As shown in the figure, for example, 2
In the adjacent portions of the gasket holes 2, 2, the shapes of both the convex portions 4, 4' are formed to overlap.

Next, the operation of this embodiment will be explained.

When the metal gasket 1 formed as described above is used as a metal gasket for a cylinder head of an internal combustion engine, as shown in FIG. two cylinder holes 7a to be sealed;
7b, 8a, 8b are aligned with the gasket holes 2, 2 of the metal gasket 1, respectively. Next, the cylinder 5 and cylinder head 6 are tightened using a tightening member (not shown) such as a tightening bolt. By this tightening, the cylinder 5 and the cylinder head 6 are fixed to each other, and the metal gasket 1 is compressed and held by the cylinder 5 and the cylinder head 6. At this time, a non-directional and uniform pear pattern S is formed on both surfaces of the metal gasket 1 by physical surface treatment such as sandblasting or chemical surface treatment such as etching. The contact surface between both surfaces of the cylinder 5 and the cylinder head 6 has a non-directional and uniform satin-like pattern S at numerous points of contact, thereby improving the sealing performance. That is, when such a satin pattern S is formed, the unevenness of the satin pattern S digs into the contact surface between the cylinder 5 and the cylinder head 6, and furthermore, due to the countless unevenness, the surface of the metal gasket 1 and the cylinder The surfaces of cylinder head 5 and cylinder head 6 are in contact with each other at numerous points, and the fluid interposed between them, such as air that fills the microscopic gap, automatically seals the cylinder due to the labyrinth effect, so the tightening pressure is reduced. It works effectively and the sealing effect is more reliable. Moreover, the metal gasket 1
Convex portions 4 and 4' are formed concentrically in the vertical direction from both surfaces of the peripheral edge 3 of the gasket hole 2 to be sealed. 6 is in contact with the two upper and lower portions of the convex portions 4 and 4' where the stress is partially increased and the sealing performance of the metal gasket 1 is further improved.

Furthermore, in this embodiment, the shapes of the convex portions 4, 4' of both gasket holes 2, 2 are made to overlap in the adjacent portion where the distance H is small, so that the distance H is small. It also has sufficient strength and can reliably prevent gas from blowing between the two gasket holes 2, 2.

Therefore, it is possible to effectively cope with scale-up due to the increase in the diameter of the cylinder holes of an internal combustion engine and the closer proximity of the cylinder holes due to the lighter and more compact design.

Further, since the metal gasket 1 of the present invention is integrally formed of metal, it has good heat resistance and thermal conductivity. In particular, if aluminum is used as the material, the material will be almost the same as the material of the internal combustion engine itself, so the thermal conductivity will be extremely high.

Note that the present invention is not limited to the above-mentioned embodiments, and can be modified as necessary.

As described above, according to the present invention, a metal gasket with a high sealing effect can be obtained without using asbestos at all, so that the gasket can be made to have good heat resistance, good thermal conductivity, and pressure resistance. Further, the metal gasket according to the present invention can have a plurality of gasket holes close to each other while maintaining sufficient sealing performance, and can be used, for example, to scale up or reduce weight and size by increasing the diameter of the cylinder hole of an internal combustion engine. In addition, since it can be manufactured using only simple operations, mainly continuous press operations, it is easy to mass-produce, resulting in low-cost products and is economically superior. .

[Brief explanation of drawings]

Fig. 1 shows a conventional gasket for a flange, where A is a plan view, B is a longitudinal sectional view, and Fig.
The figure is a plan view of a conventional cylinder head gasket for an internal combustion engine, FIG. 3 is a vertical sectional view showing a part of another conventional cylinder head gasket for an internal combustion engine, and FIG.
7 to 7 show one embodiment of the metal gasket of the present invention, FIG. 4 is a plan view showing the main parts, FIG. 5 is a sectional view taken along the line - in FIG. 4, and FIG. 4
FIG. 7 is a longitudinal sectional view of the cylinder head of an internal combustion engine to which the metal gasket of the present invention is attached. 1...Gasket. 2...Gasket hole. 3...
...periphery. 4, 4'...Protrusion. S...Nashiji pattern.

Claims (1)

[Claims] 1. For metal gaskets in which multiple gasket holes are drilled close to each other in the same plane, both surfaces of the soft metal plate are roughened to a satin-like texture by blasting, etc., and the periphery of each gasket hole is roughened. 1. A metal gasket characterized in that convex portions are formed on both surfaces in concentric circles in the vertical direction, and the shapes overlap in adjacent portions.