JPS63270976A - Gasket - Google Patents

Abstract

PURPOSE:To keep initial surface pressure good for improved gas sealing performance by providing a gasket body with a hole, and an annular and plate-shaped metallic seal ring accommodated adjacently to the peripheral surface of the hole. CONSTITUTION:A gasket body 11 is provided with a cylinder hole 15, in which a seal ring 16 formed of an annularly punched metal plate of a SPCC steel plate and a stainless steel plate or the like is fittedly fixed, and a grommet 17 made of metal such as copper, steel or stainless steel or the like is insertedly fixed to the seal ring 16 with its both surfaces held between the grommet 17. Thus, since the annular plate-shaped seal ring 16 is used for the gasket, the seal ring 16 and the grommet 17 are brought into surface contact with each other from the first stage. The initial surface pressure can therefore be kept good without decrease in compressive stress on the mounted part of the seal ring 16 with increase in compressibility to improve gas sealing performance.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a gasket, and particularly to a gasket having a seal ring and suitable as a cylinder rad gasket, an exhaust gasket, or the like.

[Conventional technology]

FIG. 4 shows a rad gasket to a cylinder with a conventional seal ring. The gasket body 1 is made up of a hook steel plate 3 with hooks 2 punched out on both sides, and a sheet material 4 crimped on both sides of the hook steel plate 3.
consists of a mixture of rubber and compressible fibers such as asbestos. The gasket body 1 is provided with a cylinder hole 5, and a steel seal ring 6 having a circular cross section is accommodated in the cylinder hole 5. A grommet 7 made of copper, steel, stainless steel, etc. is attached to the peripheral edge of the cylinder hole 5 of the gasket body 1 so as to sandwich a seal ring 6 therebetween.

In this conventional cylinder head gasket, the combustion gas inside the cylinder of the engine is sealed at the seal ring 6 installation portion.

[Problem that the invention seeks to solve]

FIG. 5 is a characteristic diagram showing the relationship between compression ratio and compressive stress at the seal ring 6 installation part of the conventional cylinder head gasket. In this conventional cylinder head gasket, the gas seal part is located in the cylinder head (hereinafter referred to as
The seal ring 6 is sandwiched between the cylinder block (hereinafter simply referred to as the block) and the cylinder block (hereinafter simply referred to as the block). At first, it is a line contact, but then the seal ring 6 becomes greatly flattened and the contact becomes a surface contact, so as the compressibility of the gasket increases, the compressive stress increases, as shown in part A of Fig. 5. On the contrary, a phenomenon occurs in which the pressure decreases, and as a result, the initial surface pressure cannot be maintained, and there is a possibility that combustion gas may leak.

In addition, the seal ring 6 is manufactured by curving a rod-shaped material with a circular cross section into a circle and welding its ends together, but the hardness of this welded part is higher than the hardness of other parts. As a result, the relationship between compressibility and compressive stress cannot be made uniform over the entire circumference of the seal ring 6, and this also poses a problem in that gas leakage may occur.

Furthermore, when manufacturing the seal ring 6 as described above, after welding both ends of the material, machining is performed to make the thickness of the seal ring 6 uniform by cutting the build-up of the welded part. There was also the problem that this was necessary as a processing step, increasing manufacturing costs.

[Purpose of the invention]

The present invention has been made to solve the above-mentioned conventional problems, and does not cause a phenomenon in which the compressive stress decreases as the compression ratio increases, maintains the initial surface pressure well, and seals. It is an object of the present invention to provide a gasket that can improve the performance, make the hardness uniform over the entire circumference of the seal ring, and also enable the seal ring to be manufactured easily and reduce the manufacturing cost of the seal ring. purpose.

[Means for solving problems]

The gasket according to the present invention includes a gasket body, a hole provided in the gasket body, and an annular and plate-shaped seal ring made of metal and housed in close proximity to the circumferential surface of the hole. It is.

[Effect]

In the present invention, since an annular and plate-shaped seal ring is used, the contact area between the seal ring and the grommet (if a grommet is not used, the contact area between the seal ring and the joint surface of the head, block, etc. to be sealed) Since the contact area (contact area) is in surface contact from the beginning and the area of the contact area does not increase significantly when compressive stress is applied as in the case of the conventional cylinder Rad gasket, the compression rate increases as the compression rate increases. Stress does not decrease on the contrary, the initial surface pressure can be maintained well, and leakage is less likely to occur.

Further, since the seal ring can be manufactured by punching or the like without using welding, it is possible to obtain a ring that has no seams over its entire circumference and has uniform hardness over its entire circumference.

Furthermore, since the seal ring can be manufactured without welding, there is no need for post-processing such as cutting the built-up part due to welding, and manufacturing costs can be reduced.

〔Example〕

Hereinafter, the present invention will be explained based on embodiments shown in the drawings.

1 and 2 show a cylinder rad gasket in accordance with one embodiment of the present invention. In this embodiment, the gasket body 11 includes a hook steel plate 1 with claws 12 punched out on both sides.
3 and a sheet material 14 crimped to both sides of the hook steel plate 13, and the sheet material 14 is made of a mixture of rubber and compressible fibers such as asbestos. The gasket body 11
A cylinder hole 15 is provided in the cylinder hole 15, and a seal ring 16 formed by punching a metal plate such as a 5 PCC steel plate or a stainless steel plate into an annular shape is fitted into the cylinder hole 15. FIG. 2 shows a plan view of the seal ring 16.

In addition, copper is placed around the periphery of the cylinder hole 15 of the gasket body 11 so as to sandwich both sides of the seal ring 16.
A grommet 17 made of metal such as steel or stainless steel is attached.

In this gasket, a plate-shaped and annular seal ring 16
is used, the contact area between the seal ring 16 and grommet 17 is a surface contact from the beginning, and when compressive stress is applied to the cylinder as in the case of the conventional cylinder rad gasket, the area of the contact area is significantly reduced. Since the compressive stress does not decrease as the compression ratio increases at the seal ring installation part, the initial surface pressure can be maintained well, making it difficult for combustion gas to leak. .

Further, since the seal ring 16 can be manufactured by punching or the like without using welding, it is possible to obtain a ring that has no seams over its entire circumference and has uniform hardness over its entire circumference.

Further, since it can be manufactured without using welding as described above, there is no need for post-processing such as cutting the built-up portion by welding.

FIG. 3 shows another embodiment of this embodiment. In this example, no grommet is attached, and the seal ring 1
6 is in direct contact with the head and block. The other configurations are the same as in the previous embodiment. Note that parts corresponding to those in the above embodiment are indicated by the same reference numerals.

In this embodiment as well, the same effects as in the previous embodiment can be obtained.

In each of the above embodiments, the gasket main body was made by pressing a sheet made of a mixture of compressible fibers such as asbestos and rubber onto a hook steel plate, but in the present invention, the gasket main body has such a structure. The present invention is not limited to this, and gasket bodies of other configurations, such as those made of laminated metal plates, can also be used.

In addition, the present invention is not limited to the cylinder rad gasket.
It can also be applied to gaskets used for other purposes such as exhaust gaskets.

〔Effect of the invention〕

As described above, the gasket according to the present invention (a) does not cause the phenomenon in which the compressive stress decreases as the compression ratio increases, maintains the initial surface pressure well, and improves the gas sealing performance. Can be done.

(b) Hardness can be made uniform over the entire circumference of the seal ring.

(c) The seal ring can be easily manufactured by punching or the like, and no post-processing is required, so the manufacturing cost of the seal ring can be reduced.

It is possible to obtain excellent effects such as.

[Brief explanation of the drawing]

Figure 1 is a sectional view showing the main parts of the gasket of the present invention, Figure 2 is a sectional view showing the main parts of the gasket of the present invention;
The figure is a plan view showing the seal ring in this embodiment, the third
The figure is a sectional view showing the main part of another embodiment of the present invention, FIG. 4 is a sectional view showing a conventional cylinder rad gasket, and FIG. 5 is the compression ratio of the gas seal part of the conventional cylinder rad gasket. FIG. 3 is a characteristic diagram showing the relationship between and compressive stress. 11...Gasket body, 15...Cylinder hole, 1
6... Seal ring.

Claims (1)

[Claims] A gasket comprising a gasket body, a hole provided in the gasket body, and an annular and plate-shaped seal ring made of metal and housed in close proximity to the circumferential surface of the hole.