JPS58225268A - Cylinder, head and gasket - Google Patents

Abstract

PURPOSE:To permit to maintain stable and prominent gas seal performance even if a high stress or a high thermal load is applied by a method wherein all of a grommet attaching part is constituted by parts made of metallic materials. CONSTITUTION:The main body 8 of the gasket is made by welding a sheet-like member 10 of non-metallic material under a pressure on both surfaces of a core plate 9 of steel. The core plate 9 is provided coaxially with cylinder holes 11 for the core plate while the sheet-like member 10 is provided with the cylinder holes 12 for the sheet-like member coaxially. A ring 13 of steel is put on the peripheral rim part 9a of the core plate 9 and the grommet 14, made of a metal such as stainless steel or the like, is mounted on both ring and core plate so as to pinch them from both sides thereof.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a cylinder head gasket having a gasket body formed by fixing sheet-like materials made of a non-metallic material to both sides of a metal core plate such as No. 11 steel plate.

In recent years, engines have tended to have higher horsepower and higher rotation speeds, and these trends have resulted in increased combustion pressure and increased thermal load. At the same time, there is a trend towards lighter engines, and this trend
This results in a decrease in the rigidity of the case. Therefore, deformation due to combustion pressure and thermal deformation due to thermal load in the cylinder head and crankcase are increasing (note that each deformation includes not only static deformation but also deformation caused by engine operation). As a result, cylinder head gaskets are being subjected to extremely large stresses and thermal loads.

However, conventional cylinder head gaskets of this type have had a structure as shown in FIG. That is, the gasket body 1 includes a core plate 2 made of a steel plate with claws 6 on both sides, and a sheet-like material made of a non-metallic material such as rubber, asbestos, composite, etc. that is crimped on both sides of the core plate 2. 3, of this gasket body 1,
A grommet 5 for sealing combustion gas in the cylinder of the engine was attached to the peripheral edge of the cylinder hole 4 so as to sandwich the gasket body 1 from both sides.

For this reason, if a large stress is applied to the grommet 5 attachment part,
When the sheet material 3 exceeds the compressive elastic limit, the entire grommet 5 fitting part also exceeds the compressive elastic limit, as shown by curve A in FIG. This has the disadvantage that it tends to deteriorate, expand the sealing gap, and eventually lead to gas leakage and damage to the grommet 5.

In addition, due to the large heat load, the sheet material 3 tends to creep in the grommet 5 mounting portion, which also causes gas leakage.

The present invention was made to eliminate the above-mentioned conventional drawbacks, and is capable of stably maintaining excellent gas sealing performance even under severe conditions where extremely large stress and thermal loads are applied. The purpose is to provide cylinder head gaskets.

A cylinder head gasket according to the present invention that achieves such an object is a cylinder head gasket having a gasket body made of sheet materials made of a non-metallic material fixed to both sides of a metal core plate. , provided on the sheet material so that a core plate cylinder hole provided in the core plate and a peripheral edge of the core plate cylinder hole of the core plate protrude from the sheet material; a cylinder hole of the sheet-like member having a diameter larger than the cylinder hole of the core plate; a metal ring superimposed on the peripheral edge of the cylinder hole of the core plate of the core plate; A metal grommet is attached to the peripheral edge of the cylinder hole of the core plate part and the ring so as to sandwich the two from both sides.6.
BEST MODE FOR CARRYING OUT THE INVENTION The present invention will now be described in more detail based on embodiments shown in the drawings.

2 and 3 show one embodiment of the invention. The gasket body 8 has a sheet material 10 made of non-metallic material such as rubber, asbestos, compound, etc. on both sides of a core plate 9 made of steel.
It is made by crimping.

The core plate 9 has a core plate cylinder hole 11, and the sheet material 10 on both sides has a sheet material cylinder hole 12.
They are provided coaxially with each other. The sheet-shaped member cylinder hole 12 is formed by the core plate cylinder hole 11.
As a result, the peripheral edge 9a of the core plate cylinder hole 11 of the core plate 9 has a larger diameter than the sheet material 1 on both sides.
Extruded from 0.

A ring 13 made by punching out a steel plate is stacked on the peripheral edge 9a of the core plate, and grommets 14 made of metal such as stainless steel are attached to both rings so as to sandwich them from both sides. There is.

Here, the core plate 9, the sheet material 10 and the grommet 14
The total lamination thickness t1 is greater than the plate thickness t2 of the gasket body 8.

In addition, 15, 16, and 17 are gasket body 1, respectively.
bolt holes, oil holes, and water holes provided in the

This cylinder head gasket includes a core plate 9, a sheet material 10 and a grommet 14 when installed between the cylinder head and cylinder block of an engine.
The grommet attachment part made of laminated layers maintains a gas seal, but since this grommet part is made entirely of metal, even when subjected to extremely large stress,
As shown by curve B in FIG. 4, the compressive elastic limit is never exceeded.

Furthermore, as mentioned above, since the grommet mounting portion is made entirely of metal, it is not prone to creep due to its material, and even if it receives a large thermal load, the thermal load will be absorbed by the grommet 14, Since heat is efficiently radiated to the outside through the path of the ring 13 and the core plate 9, the tube is even less susceptible to thermal loads.

Therefore, it is possible to stably maintain excellent gas sealing performance even under severe conditions where extremely large stress and thermal loads are applied.

As described above, the cylinder bed gasket according to the present invention can withstand extremely large stresses and thermal loads.
This provides an extremely useful effect of being able to maintain stable and excellent gas sealing performance.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing a portion of a conventional cylinder head gasket near the cylinder hole, and FIG. 2 is a plan view showing an embodiment of the cylinder head gasket according to the present invention.
FIG. 3 is a sectional view taken along the line 1--2 in FIG. 2, and FIG. 4 is a compressive stress-strain diagram of the conventional gasket and the grommet attachment portion in the embodiment. 8... Gasket body, 9... Core plate, 9a... Periphery of core plate cylinder hole of core plate, 10... Sheet material, 11... Core plate cylinder hole, 12... Sheet-like material cylinder hole, 13... Ring, 14... Grommet.

Claims (1)

[Claims] A cylinder head equipped with a gasket body made by fixing non-metallic sheet materials to both sides of a metal core plate.
In the gasket, the sheet material is provided in such a manner that a core plate cylinder hole provided in the core plate and a peripheral edge of the core plate cylinder hole of the core plate protrude from the sheet material. Further, a sheet-like member cylinder hole having a diameter larger than the core plate cylinder hole, a metal ring superimposed on a peripheral edge of the core plate cylinder hole of the core plate, A cylinder head gasket comprising a metal grommet attached to the peripheral edge of the cylinder hole of the core plate part of the plate and the ring so as to sandwich the two from both sides.