JP2004028219A - Cylinder head gasket - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a metal cylinder head gasket disposed in such a state as fitted to characteristics of a rubber material, and disposing a strong bearing pressure in a place required a strong bearing pressure and an appropriate bearing pressure in a place with low loading pressure by selecting a combination layer shape. <P>SOLUTION: This cylinder head gasket for use in an internal combustion engine is so formed that a fiber reinforced rubber coating 5 is applied to one surface of a metal core metal plate 4, the circumference of a bore part 31 is wrapped with a bore grommet 6, a seal rubber 7 is provided in the circumference of a hole part in the rear surface, and a hard space plate 8 is disposed on a surface excluding the seal rubber 7 and the bore grommet 6 in the rear surface. This constitution allows to set the sharing rate of a high pressure part high, set the sharing rate of the low pressure part low, and suppress the whole axial force to low. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
[Industrial application fields]
The present invention relates to a cylinder head gasket made of a metal plate for use in an engine cylinder head, and more particularly to improvement of a cylinder head gasket formed by baking an elastic material.
[0002]
[Contents of prior art]
Conventionally, as a cylinder head gasket made of metal that efficiently seals a joint surface between a cylinder head and a cylinder block of an internal combustion engine, a bead having a convex cross section is formed on a metal plate having elasticity, and the peripheral surface of the cylinder bore is formed by the bead. Metal cylinder head gaskets have been proposed and put into practical use.
In general, the entire surface is coated on both surfaces with a sealing elastic material based on a rubber material in order to further improve the sealing performance. This will be explained with reference to the drawings. As shown in FIG. 4, a cylinder head gasket structure (for example, a sheet material (2) having elasticity is fixed to both sides of a metal plate (1) and punched into a desired shape (for example, JP-A 63-96359) is used.
[0003]
[Problems to be solved by the invention]
However, in the cylinder head gasket in which the sheet-like material (2) is fixed to the metal plate material (1) as described above, it is difficult to say that the configuration can flexibly cope with the difference in pressure of the seal hole or the difference in sealing purpose. .
That is, generally, as shown in FIG. 5, the sealing surface between the cylinder head and the cylinder block of the engine has a bore (31), a water hole (32), an oil hole (33), a blow-by gas hole (34), and a bolt. The holes (35) and the like are interspersed, and these have different pressures in the holes. Particularly, the pressure difference between the bore (31) and the blow-by gas hole (34) is extremely large, and these are sealed at the same time. In order to achieve this, it is necessary to apply the maximum necessary and strong tightening pressure to the entire surface of the cylinder head and the cylinder block, so that an efficient tightening operation is not brought about.
[0004]
In order to dislike this, according to each request, a surface pressure adjusting material (not shown) is provided in order to provide a high surface pressure at a location where a high surface pressure is required and an appropriate surface pressure at a location where the pressure load is low. May be partially inserted, but this naturally increases the cost.
[0005]
The present invention has been made in view of such drawbacks, and is made of a metal cylinder gasket that can be arranged in accordance with the characteristics of a rubber material and can exhibit high sealing performance by selecting a combination layer shape. The purpose is to provide.
[0006]
[Means for Solving the Problems]
The present invention is a cylinder head gasket made of a core metal plate and a rubber material mounted between a cylinder head (b) and a cylinder block (a) for an internal combustion engine, and will be described with reference to the drawings. As shown in FIG. 3, the cylinder head gasket has a rubber coating (5) containing fibers on one surface of a metal core plate (4). As shown in FIG. 4) and the periphery of the bore portion (31) of the rubber coating (5) is wrapped with a bore grommet (6), and the water hole (32) on the back surface of the metal core plate (4) coated with the rubber coating (5) A seal rubber (7) is provided around the oil hole (33), blow-by gas hole (34), bolt hole (35), etc., and a hard space plate is attached to the surface excluding the seal rubber (7) and bore grommet (6) on the back surface. (8) arranged It is characterized in that occupied.
[0007]
Further, in the cylinder head gasket, as shown in FIG. 2, the metal core plate (4) is rubber-coated (5) with a rubber material containing fiber on one surface, and the metal core plate (4) and the rubber coating are coated. The periphery of the bore portion (31) of (5) is wrapped with a bore grommet (6), and FIG. 3 shows a water hole (32) and an oil hole on the back surface of the rubber coating (5) of the metal core plate (4). 33), the bead (9) is formed by projecting the periphery of the blow-by gas hole (34), the bolt hole (35), etc., and the metal space on the surface excluding the bead (9) and the bore part (31) on the back surface It is characterized by disposing a plate (8).
[0008]
DETAILED DESCRIPTION OF THE INVENTION
As described above, the cylinder head gasket according to the present invention is mounted between the cylinder head (b) and the cylinder block (a), and these are fastened with bolts, and a high-pressure portion that seals the periphery of the bore portion (31); , The sharing of the bolt axial force of the low pressure part such as the water hole (32), the oil hole (33) or the blow-by gas hole (34), the sharing ratio of the high pressure part is set high, and the sharing ratio of the relatively low pressure part is set low By doing so, the axial force of the entire cylinder head gasket can be kept low.
In other words, in the present invention, the seal rubber (7) is provided to the water hole (32), the oil hole (33), the blow-by gas hole (34) and the like while securing the load on the bore part (31) by the bore grommet (6). The load is kept low and the load followability to the cylinder head is improved.
[0009]
【Example】
FIG. 1 is a sectional view showing an embodiment of a cylinder head gasket according to the present invention, and FIG. 2 is a sectional view of an embodiment of a bore portion. FIG. 3 is a cross-sectional view of an embodiment of a seal rubber, and FIG. 4 is a cross-sectional view showing a conventional example. FIG. 5 is a plan view of the cylinder head gasket. FIG. 6 shows another embodiment of the present invention.
FIG. 1 shows a basic configuration of the present invention.
[0010]
In the present invention, the rubber coating (5) is baked and formed on the metal core plate (4) and the periphery of the bore (31) is wrapped with the bore grommet (6) in order to set the share of the low pressure portion low. As shown in FIG. 1, the total thickness (T0) of the bore grommet (6) wrapping the metal core plate (4) and the rubber coating (5) is set to the metal core plate (4) and the rubber coating. It is formed thicker than the thickness (T1) consisting of (5) and the hard space plate (8).
As shown in FIG. 2, the rubber coating (5) around the bore can be disposed with a bore grommet (6) with the rubber coating (6) being removed. The thickness (T0) is formed to be thicker than the thickness (T1) composed of the metal core plate (4) and the hard space plate (8).
[0011]
As an example, the metal core plate (4) is 0.35 mm, the rubber coating (5) is 0.2 mm, the hard space plate (8) is 0.2 mm, and the total thickness is as follows. A cylinder head gasket in which (T1) is 0.75 mm and the total thickness (T0) of the bore grommet (6) is 0.8 mm can be shown.
[0012]
Further, in place of the seal rubber (7) or in combination with the seal rubber (7), the water hole (32), oil hole (33), gas hole (34) or bolt hole (35) on the back surface of the rubber coating (5), etc. It is also possible to dispose a bead (9) protruding from the metal core plate (4) or having a step in the periphery of the metal core plate (4), and this is selected when it is desired to increase the load of the disposition portion. Here, it is important that the thickness (t0) of the seal rubber (7) is thicker than the thickness (t1) of the hard space plate.
[0013]
In addition, when the cylinder head gasket is attached to the engine, as shown in FIG. 6, the rubber-coated (5) surface is directed toward the cylinder block (a) where the temperature is high to ensure heat-resistant sealing performance. It can be set as the arrangement | positioning which absorbs the shift | offset | difference by a temperature difference toward the cylinder head (b) toward the cylinder head (b).
[0014]
Synthetic rubber NBR (nitrile butadiene rubber) is generally used as the rubber material for forming the rubber coating (5) or the seal rubber (7) used here. For example, H-NBR (hydrogen Additive nitrile butadiene rubber), ACM (acrylic rubber), AEM (ethylene acrylic rubber), VQM (fluorine rubber), FKM (silicone rubber), FVQM (fluorosilicone rubber), etc. can be used according to the required performance If it is a sealing material to be used, there is no need to define it.
On the other hand, as fibers mixed with the rubber coating (5), various kinds of compressible inorganic fibers or compressible organic fibers not containing asbestos are employed.
[0015]
【The invention's effect】
As described above, according to the present invention, the cylinder head gasket according to the present invention distributes the bolt axial force between the high pressure portion around the bore portion (31) and the low pressure portion in which various hole portions are scattered. The share ratio of the low pressure part is set low and the axial force of the entire gasket is kept low, giving a uniform tightening pressure to each sealed part at an appropriate surface pressure. And can be used for sealing purposes. This enables tightening with a low load, prevents stress relaxation, and maintains good restoring force and conformability for a long period of time.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing an embodiment of the present invention.
FIG. 2 is a cross-sectional view showing another embodiment of the present invention.
FIG. 3 is a sectional view showing another embodiment of the present invention.
FIG. 4 is a cross-sectional view showing a conventional structure not using the present invention.
FIG. 5 is a plan view of a cylinder head gasket.
FIG. 6 is a cross-sectional view showing another embodiment of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Metal plate material 2 Sheet-like material 31 Bore part 32 Water hole 33 Oil hole 34 Blow-by gas hole 35 Bolt hole 4 Metal core metal plate 5 Rubber coating 6 Bore grommet 7 Seal rubber 8 Hard space plate 9 Bead a Cylinder block b Cylinder head

Claims (7)

In a cylinder head gasket made of a metal core plate and rubber material, with a bore, water hole, oil hole, gas hole, bolt hole, etc. cut and arranged,
Rubber coated with fiber material on one side of metal core plate,
Wrapping around the bore of the metal core plate and the rubber coating with a bore grommet,
A seal rubber is provided around a water hole, an oil hole, a gas hole or a bolt hole on the back surface of the rubber-coated metal core plate,
A cylinder head gasket, wherein a hard space plate is disposed on a surface other than the seal rubber on the back surface. The total thickness of the bore grommet that encloses the metal core metal plate and the rubber coating is formed to be thicker than the thickness of the metal core metal plate, the rubber coating, and the hard space plate. Cylinder head gasket. 3. The cylinder head gasket according to claim 1, wherein the thickness of the seal rubber is larger than the thickness of the hard space plate. The cylinder head gasket according to any one of claims 1 to 3, wherein a rubber coating around a bore wrapped by the bore grommet is eliminated. 5. The cylinder head gasket according to claim 1, wherein the hard space plate is made of metal or a rubber sheet containing fibers. In cylinder head gasket,
Rubber coated with fiber material on one side of metal core plate,
Wrapping around the bore of the metal core plate and the rubber coating with a bore grommet,
The bead is protruded around the water hole, oil hole, gas hole or bolt hole on the back surface of the rubber coating of the metal core plate, and a seal rubber is provided on the bead surface,
A cylinder head gasket, wherein a hard space plate is disposed on a surface other than the bead on the back surface. In the cylinder head gasket,
The rubber-coated surface is directed to the cylinder block,
The cylinder head gasket according to any one of claims 1 to 6, wherein the side on which the seal rubber is provided is arranged facing the cylinder head.

Images