JPS59218343A - Cylinder head gasket - Google Patents

Abstract

PURPOSE:To improve the sealing property of a gasket for a cylinder head by adopting a metal-made core material for the gasket, providing a metallic ring on a grommet part surrounding said gasket, and forming a bead around a water hole. CONSTITUTION:A core material 13 for a gasket 12 for a cylinder head is made of a copper plate, etc., and a surface material 14 comprising mixed asbestos and rubber on the upper and lower surfaces of said gasget is provided. A metallic ring 22 is overlapped on the periphery of the gasket, and a metal-made grommet 23 is provided holding said ring from both sides thereof, said grommet making contact with the core material 13 at a notched part of a lower side surface material 14 and with an upper side surface material 14. Hereby, the total thickness t1 of the grommet part can be set to a slightly thicker state than the thickness t2 of the gasket 12. Further, an annular bead 18 is formed around a water hole 16 part, securing the sealing property of the gasket upon tightening it.

Description

Detailed Description of the Invention [Technical Field] The present invention relates to a cylinder head gasket interposed between a cylinder head and a cylinder block of an engine. This is the first stage of increasing horsepower and increasing engine speed, and this trend is causing an increase in combustion pressure and thermal load. At the same time, engines are becoming lighter in weight, and this trend is causing a decrease in the rigidity of the cylinder head (hereinafter simply referred to as the head) and the cylinder block (hereinafter simply referred to as the block). is bringing. Therefore, the structural deformation of l\rad and block due to combustion pressure and thermal deformation due to thermal load are as follows:
It is rapidly increasing.

FIG. 1 shows the movement of the head d3 and the block due to the structural deformation. In this figure, 1 is the head, 2 is the cylinder head gas get, 3 is the block, arrow A is the expansion of the cylinder bore due to combustion pressure, and arrow B is the combustion pressure. Show each movement. J, T, Arrow C indicates stress caused by combustion pressure, widening of the gap between head 1 and block 3, and sealing stress on bolts (not shown) that attach head 1 to block 3. The arrow indicates the movement of the head surface.

On the other hand, FIG. 2 shows the thermal deformation of the head 1 and block 3! ζ, arrow E indicates vertical change in the seal gear 11, arrow F indicates horizontal movement of gasket 2, arrow G indicates thermal expansion of the cylinder, and arrow 1-1 indicates deflection of the head surface.

Under such environmental conditions d3, the cylinder head gasket does not simply contact statically with head IJ3J and block 3, but dynamically contacts it. Therefore, the environmental conditions are extremely harsh.

However, in the past, cylinder head gaskets made by compressing sheet-like surface materials made of non-metallic materials on both sides of a steel plate, as illustrated in FIG. 3, have been commonly used.

To explain in more detail the structure of the conventional cylinder head gas slit shown in FIG. 3, the gasket 1 to the main body 4 are
It consists of a steel plate 6 with claws 5 punched out on both sides, and a surface material 7 crimped to both surfaces of the steel plate 6, and the surface material 7 is made of a compound of rubber and asbestos. A gasket 9 for sealing the combustion gas in the cylinder of the engine is placed on the peripheral edge of the cylinder hole 8 of the gasket L-Kiyū 4) 5 on both sides of the peripheral edge. It is decorated in a way that makes it look like it is.

In addition, a liquid gasket 11 is applied around the water holes or oil holes 10 of the gaskets 1 to the main body 4. Alternatively, a rubber ring may be fitted into the water or oil hole 10).

In such a conventional cylinder head gasket, (a) When a large stress is applied to the grommet 9 attachment part,
Since the surface material 7 exceeds the compressive elastic limit C, the grommet 9 mounting portion as a whole also exceeds the compressive elastic limit, as shown by curve P in FIG. As a result, the sealing stress decreases, the sealing gap widens, and this tends to lead to gas leakage and failure 10 of the mesh 9 of the groove 1-1.

(b) Due to a large thermal load, the grommet 9
In the wearer's part, the surface material 7 tends to creep.
This also tends to cause gas leakage.

(c) The areas around the water holes and oil holes 10 tend to be poorly sealed, so if you apply a liquid gasket 11 or attach a rubber ring as described above, it is difficult to perform these operations. (This takes a lot of time and reduces productivity.In addition, when applying the liquid gasket 11, it is necessary to
You can only increase the Besa Seal effect by 10.

(d) Sufficiently seal around the water hole and oil hole 10.
If the tightening force is too large, an excessive force will act on the surface material 7 at the periphery of the bolt, exceeding its compressive elastic limit, and the gasket body 4 will break. Let's do C.

There were various drawbacks such as.

[Purpose of the invention]

The present invention was made in consideration of these circumstances, and
It is possible to maintain stable and excellent gas sealing performance even under severe environmental conditions with extremely large stress and thermal negative conditions, and the tightening force of Pol 1 ~ can be increased. C
The purpose is to provide a cylinder head gasket that can

[Structure of the invention]

J in L: Cylinder head gasket according to the present invention which achieves the following objectives] ~ is made by fixing a surface material made of a mixture of compressible fibers and a lastomer to both sides of a metal core plate. A gasket (one body, a shell passed through the gasket body, 1 = water hole A3 and an oil hole, formed in the gasket body so as to surround the water hole and the oil hole 1)
a bead portion, a core plate cylinder hole provided in the core plate, the core plate cylinder hole of the core plate, which is installed in the surface material and has a larger diameter than the core plate cylinder hole; a cylinder hole in the surface material part that causes the peripheral edge of the surface material to protrude from the surface material;
A metal ring superimposed on the peripheral edge of the core plate cylinder hole of the core plate, and a metal ring superimposed on the peripheral edge of the core plate cylinder hole of the core plate, J, and the ring. Place both hands on both sides 1) with the attached metal grommet 1 on the right.

〔Example〕

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

4 to 6 do not show one embodiment of the present invention. In this embodiment, as shown in FIG. 5, the gaskets 1 to 12 are made of a core plate 13 made of metal such as a steel plate, and asbestos that is crimped or caulked on both sides of the core plate 13. The surface material 14 is made of a rubber mixture.

As shown in FIG. 4, the gaskets 1 to 12 have a port 1 hole 15, a water hole 16 for passing cooling water, and an oil hole 17 for passing lubricating oil. is penetrated. Further, in the vicinity of the water hole 16 and the oil hole 17 in the gasket body 12, there are holes 1 and 1, respectively.
6.17, a bead portion 18.19 having an arcuate cross section and an annular shape is formed by press working (only the cross-sectional shape of the bead portion 18 is shown in Fig. 5). , the cross-sectional shape of the bead portion 19 is also similar to that of the bead portion 18).

A core plate cylinder hole 20 is provided in the core plate 13, and a surface material cylinder hole 21 is provided in the surface material 14, coaxially with each other. Since the surface material cylinder hole 21 has a larger diameter than the core plate cylinder hole 20, the peripheral edge 13a of the core plate cylinder hole 20 on the periphery of the core plate 13 is separated from the surface material 14 on both sides. It is prominent.

A ring 2 formed by punching a steel plate is provided on the peripheral edge i3a.
A grommet 23 made of metal such as stainless steel is attached to the peripheral edge 13a of the ring 22 so as to sandwich the two from both sides. The total thickness 11 of the C1 core plate 133, surface material 14, and grommet 23 is greater than the thickness t2 of the gasket body 12.

In this cylinder head gasket, core plate 1
3. The grommet device, which is made up of a laminated surface material 14 and grommet 23, maintains a gas seal, but since this grommet attachment part is entirely made of metal, it is subject to very large stress. Even if the curve Q in Figure 7
As shown in Figure 2, the compressive elasticity limit is never exceeded, and therefore the sealing stress does not decrease, the sealing gap widens, and gas leakage and damage to the grommet 23, etc., do not occur as in the conventional case.

In addition, as shown in (e) above, the grommet device part is made entirely of metal, so it is not prone to creep due to its material, and it also becomes b1g under thermal load] Met 23,
Through the path of the ring 22 and core plate 13, it is efficiently transferred to the outside b5! Because it is heated, it is even less susceptible to thermal loads. therefore.

It can sustain stable and excellent gas sealing performance even under heavy thermal loads.

In addition, since the cylinder head gasket J3 is provided with bead portions 18 and 19, the contact area with the head A3 and the block is limited, so small bolt tightening is possible. , a contact pressure of -1-min can be obtained around the water hole 16J3 and the oil hole 17. Therefore, the area around the water hole 16 and the oil hole 17 can be sealed extremely well with a small force.

The bead portions 18 and 19 can be formed by press working, so when applying liquid gaskets 1 to 11 around the water hole J5 and oil hole, or attaching a rubber ring, as in the conventional case. In comparison, the productivity of cylinder head gaskets can be greatly improved.

In the above embodiment, the surface material is made of a mixture of asbestos and rubber, but in the present invention, instead of the asbestos, other types of compacted material such as Keppra (trade name, manufactured by Decobon Co., Ltd.) may be used. It goes without saying that rubber fibers and other types of elastomers may be used instead of the rubber.

〔Effect of the invention〕

As described above, the cylinder head gasket (~) according to the present invention is as follows: (a) Since the grommet attachment part is entirely made of metal, even if a very large stress is applied, the grommet attachment part will not exceed the compressive elastic limit. C1 Unlike the conventional method, there is no reduction in sealing stress, expansion of the sealing gap, or gas leakage or damage to the grommet.

([l)] Since the fitting part 1 to J is entirely made of metal, it is not easily affected by thermal loads, and a large amount of thermal load can be avoided.
Even when the temperature is high, stable and excellent gas sealing performance can be maintained.

(c) Water hole a3 By providing a pead part around the oil hole, sufficient contact pressure is generated around the water hole and the oil hole, so a small hole] ~ Tightening 4 =
It is possible to seal the area around the water hole and oil hole very well by applying force.

(d) By forming the heat part by press working, there is no need to apply a liquid gasket around the water hole a-3 and oil hole or install a rubber ring. - Productivity of head gaskets 1 to 1 can be improved.

There is b O) U' that can obtain the excellent effect of a hat.

[Brief explanation of drawings]

Figure 1 is an explanatory diagram showing the movement of the head and block depending on the combustion pressure, Figure 2 is an explanatory diagram showing the thermal deformation of the head and block, and Figure 3 is an explanatory diagram of the conventional cylinder head.・A sectional view showing the casquera h; FIG. 4 is a plan view showing an embodiment of the cylinder head gasket 1- according to the present invention;
FIG. 5 is a cross-sectional view taken along the line V-V in FIG. The plan view, FIG. 7, shows the conventional cylinder head gasket 1 shown in FIG. 31.
It is a compressive stress-strain diagram showing the relationship between the compressive stress and strain of the 1-1 met wearing part in the case of ~ and the case of the above-mentioned example. 12... Gasket body, 13... Core plate, 13a.
...Peripheral edge of the cylinder hole of the core plate part of the core plate, 14...
・Surface material, 16... Water hole, 17... Oil hole, 18',
19... Bead part, 20... Core plate part cylinder hole, 2
1... Surface material part cylinder hole, 22... Ring, 23
...-Grommet. Special h' [Applicant 1-Zan Gasket Co., Ltd. Agent
Patent Attorney Omori Tobu + 1;, 1 ;'l 2 i'. Figure 4 12 Figure 6

Claims (1)

[Claims] A gasket 1 body made of a metal core plate with a surface material made of a mixture of compressible fibers and a lastomer fixed to both sides, water holes and oil holes made through the gasket I body, etc. The gas cut body includes an LC bead portion formed to surround the front water distribution hole and the oil hole, a core plate portion cylinder hole provided in the core plate, and a cylinder hole provided in the surface material, which is provided in the core plate. a surface material cylinder hole having a larger diameter than the core plate cylinder hole of the core plate and protruding a peripheral edge of the core plate cylinder hole of the core plate from the surface material; and a surface material cylinder hole of the core plate of the core plate. A metal ring attached to the peripheral edge of the hole, a metal ring attached to the peripheral edge of the cylinder hole of the core plate part of the core plate, and the ring so that both of them are heated from both sides. Silonda head gasket I- with grommet.