JPS63101574A - Gasket - Google Patents

Abstract

PURPOSE:To enhance sealing performance by fitting a grommet around the inner circumferential periphery of the through hole in a gasket body, and projectedly providing bead parts on the gasket body so as to surround the grommet. CONSTITUTION:A gasket body 1 is interposed between a cylinder head 2 and a cylinder block 3. A through hole 5 is bored in the gasket body 1, and further a grommet 6 consisting of a stainless material is fitted around the inner circumferential periphery of the through hole 5. Further, bead parts 7 surrounding the grommet 6 are projectedly provided on the gasket body 1. Thus, a double sealing part consisting of the grommet and bead parts can be formed, and the sealing performance can be enhanced.

Description

DETAILED DESCRIPTION OF THE INVENTION "Field of Industrial Application" The present invention relates to a gasket used for a cylinder head gasket, an exhaust manifold gasket, etc. of an automobile engine.

``Prior Art'' Conventionally, at least in the sealing part, a through-hole that serves as a high-pressure part to be sealed, such as a cylinder pore or an exhaust passage, is bored in a single plate-shaped gasket body, and a bead part is formed around this through-hole. A protruding gasket is known (Utility Model Application No. 57-59952).

Additionally, gaskets are known in which the gasket body is constructed by stacking multiple sheets of plate material, a through hole is drilled in the gasket body to serve as a high-pressure area to be sealed, and a grommet is attached to the inner periphery of the through hole. (Unexamined Japanese Patent Publication No. 5
No. 8-225268).

``Problems to be Solved by the Invention'' The above-mentioned gasket in which a bead portion is provided protruding from a single plate-shaped gasket body has a simple structure and can be manufactured at low cost, but explosion pressure is not directly applied to the bead portion. Since repeated stress acts on the product, there is a risk that cracks may occur due to fatigue. In order to prevent this, for example, it would be expensive to manufacture it from a highly durable stainless steel material.

On the other hand, in a gasket in which the gasket body is constructed by stacking multiple plates and a grommet is attached to the inner peripheral edge of the through hole, only the grommet part can be manufactured from the stainless steel material, but the gasket body The structure was complicated.

Furthermore, each of the above gaskets had a high usability because the main sealing part was a bead part or a grommet, and if leakage occurred in that part, the entire gasket would leak immediately.

[Means for Solving the Problems] In view of such circumstances, the present invention provides a through-hole, which is a high-pressure part to be sealed, in one plate-shaped gasket body at least in the sealing part. A grommet is attached to the inner peripheral edge of the hole, and a bead portion surrounding the grommet is protruded from the gasket body.

"Function" According to such a structure, it is possible to prevent the gasket structure from becoming complicated as much as possible, and since it has a double sealing part of the grommet and the bead part, the main sealing part is the grommet. If there is a leak in that part, the leak can be sealed next with the bead part, thus making it possible to perform a more reliable seal than in the past.

"Example" The present invention will be explained below with reference to the illustrated embodiment.
In FIG. 2, the gasket includes a plate-shaped gasket body 1 made of one steel plate, especially mild steel, and as shown in FIG. It is interposed in between.

The gasket body 1 is provided with a through hole 5 having a diameter larger than the inner diameter of the cylinder pore 4, and a grommet 6 made of stainless steel is attached to the inner peripheral edge of the through hole 5. In the illustrated embodiment in which a bead portion 7 surrounding the cylinder is protruded, the bead portion 7 is adjacent to each other on a concentric circle and protrudes in opposite directions to each other, that is, toward the cylinder rod 2 and the cylinder block 3. There is.

At this time, when the higher of the heights hl and h2 of the bead portion 7 with respect to the surface of the gasket body 1 is defined as H, the height H is greater than the thickness t of the grommet 6 in the natural state. The cylinder block 3 is also set so that the gasket is inserted between the cylinder block 2 and the cylinder block 3.
When the grommet 6 is tightened to the cylinder block 3, are the upper and lower surfaces of the grommet 6 connected to the cylinder head 2 and cylinder block 3?
! At the same time, the tops of the respective bead portions 7 are securely brought into close contact with the cylinder rad 2 and the cylinder block 3. That is, when one or more bead portions 7 are provided, the top of each bead portion 7 is placed on the mating material so that the grommet thickness t is smaller than the maximum bead height H among the heights of each bead portion. Just make sure they are in close contact.

According to the above configuration, the gasket can be manufactured from the gasket main body 1 made of one sheet of steel and the grommet 6 made of stainless steel, so that it can be manufactured at low cost. Since the seal can be performed using the grommet 6 made of stainless steel, which has excellent heat and corrosion resistance, you can expect a good seal for a long time, and in the unlikely event that the grommet 6 leaks. However, the bead portion 7 can reliably seal the leakage.

In this application, "surrounding a grommet" means that the bead part surrounds the grommet partially or multiple times, it includes surrounding multiple grommets, and of course it includes various forms such as partially enclosing the grommet twice. It is something.

Further, even if the gasket body l is made of mild steel, the gas leaking through the grommet 6 acts on the bead portion 7, so that explosion pressure acts directly on the bead portion 7, causing fatigue. Even if the bead portion 7 and the cylinder head 2 or cylinder block 3 have surface roughness, if the gasket body 1 is made of mild steel, the bead portion 7 will adhere well to the mating material. do,
Even minute leaks will be reliably prevented. Of course, in order to further ensure sealing performance, the gasket body 1 may be coated with a resin or the like.

Next, FIG. 3 shows another embodiment of the present invention, in which one bead portion 7 is attached to the gasket body 1 to the cylinder head 2.
The through hole 5 of the bead portion 7
A portion 8 is formed parallel to the clamping surface of the cylinder head 2 or cylinder block 3 from the middle position on the side. As with the other embodiments, the direction in which the bead portion protrudes is upside down.

That is, in this case, it can be placed on the cylinder block 3 side.

In this embodiment, by tightening the cylinder head 2 to the cylinder block 3, the top of the bead 7 is brought into close contact with the cylinder rad 2 with a high surface pressure, and as a result, the through-hole 5 of the bead 7 The base 9 on the opposite side comes into close contact with the cylinder block 3 with a relatively high surface pressure. Therefore, in this embodiment as well, substantially the same effects as in the above embodiment can be obtained.

Furthermore, in the embodiment shown in FIG. 4, one bead portion 7 is provided on the gasket body l so as to protrude toward the cylinder Rad 2, and the portion 10 on the side of the through hole 5 from the bead portion 7 has a height of the bead portion 7. In the embodiment shown in FIG. 5, the part 10 in the embodiment shown in FIG. 4 is continued to the bead 7. It was formed by Furthermore, the embodiment shown in FIG. 6 is different from the embodiment shown in FIG. 5 in that a plate-shaped gasket member 11 is stacked on the outer side of the bead portion 7 around the through hole 5, that is, at least in the sealing part, the gasket body 1 is taken as one sheet.

It is clear that in these embodiments as well, the top and base 9 of the bead portion 7 can be brought into close contact with the cylinder head 2 or the cylinder block 3, so that the same effects as described above can be obtained.

Note that the gasket member 11 can be provided in other embodiments as well, and can be superimposed on the upper and lower surfaces of the gasket body 1 shown in FIG. 2, for example, on the outer side of the bead portion 7. Furthermore, it goes without saying that the direction in which each bead portion 7 projects can be reversed for each embodiment. Further, in the above embodiments, the grommet 6 is provided in the cylinder bore 4, but the grommet 6 may be used in a portion surrounding a water hole, a sleeve hole, etc., or may be used in an exhaust manifold gasket or the like.

"Effects of the Invention" As described above, since the present invention has a double sealing part of the grommet and the bead part, the grommet seals first, and if that part leaks, the bead part is next sealed. Since it is possible to seal the leakage at the part, it is possible to perform more reliable sealing than in the past.

Moreover, in the present invention, since the grommet is attached to one plate-shaped gasket body at least in the sealing part, for example, the gasket body can be made of a soft steel plate, and the grommet can be made of a stainless steel material. This provides the effect that the above-mentioned excellent sealing performance can be ensured while simplifying the configuration of the gasket and manufacturing it at low cost.

In addition, since the grommet is independent from the gasket body, the shape and precision of the formed bead, or the wall thickness around the bead, will not be adversely affected when installing the grommet. It has the effect of preventing sink marks, etc.). Therefore, sufficient sealing performance can be ensured at the bead portion, and together with the effect of the grommet, a gasket having excellent sealing performance can be provided at a low cost.

[Brief explanation of the drawing]

FIG. 1 is a plan view of essential parts showing one embodiment of the present invention, FIG. 2 is a cross-sectional view taken along line II-II in FIG. 1, and FIGS. 3 to 6 are other embodiments of the present invention. It is a sectional view showing an example. 1... Gasket body 2... Rad to cylinder 3
...Cylinder block 4...Cylinder pore 5...
・Through hole 6...Grommet 7...Bead part 9...Base 11...Cleaning and recess of gasket member drawing: (No change in content) No. 1 Draft procedure amendment (voluntary) November 1988 17th, 1986 Patent Application No. 246314 2, Name of the invention Gasket 3, Relationship with the case of the person making the amendment Patent applicant Address 3-65 Midorigaoka, Toyota City, Aichi Prefecture Name Taiho Kogyo Co., Ltd. Representative Takeshi Okano 4 , agent drawings. 6. Details of amendments Figures 1 to 6 will be revised as shown in the attached sheet. ≦),

Claims (3)

[Claims] (1) At least in the sealing part, a through-hole is formed in one plate-shaped gasket body, which is the high-pressure part to be sealed, and a grommet is attached to the inner peripheral edge of the through-hole, and the grommet is attached to the gasket body. A gasket characterized by a surrounding bead portion that protrudes. (2) The gasket according to claim 1, wherein the bead portions are provided protrudingly from both sides of the gasket body. (3) The gasket according to claim 1 or 2, wherein a gasket member is superimposed on the gasket main body on the outside of the bead portion with the through hole as the center.