JPS6216538Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement of a metal laminated gasket for internal combustion engines.

Generally, gaskets for internal combustion engines are made by punching a gasket sheet into a predetermined shape, which is made by laminating a flexible material sheet such as a coating or sheet of asbestos or an asbestos rubber admixture to a wire mesh or a metal plate with a hook. Most of them were composed.

However, in recent years, as engines have become smaller and lighter, the rigidity of the engines themselves has decreased, and the temperature of engines has tended to increase during operation to prevent exhaust gases. Therefore, for example, a significant temperature difference occurs between the exhaust side and the suction side, and this temperature difference causes thermal distortion in the cylinder joint, causing local differences in the surface pressure of the sealing part. The gasket substrate, which is a rubber-asbestos organic material mainly composed of rubber and asbestos, has a significantly reduced amount of recovery due to deterioration due to heat, and the gasket itself has a flat structure, so it is difficult to absorb the strain on the joint surface. As a result, gas blows through from areas where the surface pressure has decreased, or water, oil, etc. leak, resulting in a reduction in the sealing effect.

Therefore, recent progress has been made in the technological development of metal laminated gaskets that are less susceptible to such heat deterioration. However, conventional metal laminated gaskets are
In addition to providing uneven beads at desired positions on the board, the sub-plates attached to both sides of the board are made of a material such as Cu or Al that is softer than the board, thereby reducing the surface roughness of the joint surfaces of the cylinder head and cylinder block. A method of absorbing energy is used. However, in a metal laminated gasket with such a structure, the compression recovery property does not deteriorate due to heat compared to a rubber asbestos gasket, and the spring force can be freely applied by changing the thickness of the substrate and the width of the bead. It has the advantage of being able to be increased or decreased and maintain compression recovery, but on the other hand, because the joint surface of the cylinder head and cylinder block is cut with a tool during machining, so-called tool marks are formed on the cut surface, and the tool Marks may form deep. When the tool mark becomes deeper, there is a drawback that the sealing performance against water, oil, etc. is inferior to that of asbestos-based gaskets when the tightening surface pressure is low. Furthermore, as a result of forming a bead on the substrate to form a three-dimensional gasket, a new problem has arisen in that leakage occurs from the bonding surface between the substrate and the hard sub-plate. This is because the bonding surface between the bead formed on the substrate and the hard sub-plate becomes rough over time and the adhesion deteriorates. Therefore, it may be possible to lower the hardness of the material of the sub-plate to improve the adhesion between the sub-plate and the joint surfaces of the cylinder head, cylinder block, and substrate, but in this case, the roughness of each joint surface may be reduced. This will improve the sealing performance, but if the sub-plate is made of a material that further softens due to high temperatures, the uneven beads on the board will sink into the sub-plate too much and the uneven beads will not be compressed, resulting in damage to the board. There is a problem that elastic resilience cannot be used effectively. Furthermore, the interposition of a gasket, which is a foreign substance, on the joint surface of the cylinder head and cylinder block generally reduces thermal conductivity, but especially in the case of laminated gaskets, since multiple materials of different materials are laminated, the thermal conductivity increases. There is a problem that thermal conductivity deteriorates.

The purpose of the present invention was to eliminate such drawbacks, and the sub-plates made of hard metal plates are arranged in parallel on both sides of a substrate made of an elastic metal plate having beads, and the entire surface side of each sub-plate is The area corresponding to the bead on the back side is coated with a soft sealing material to maintain thermal conductivity and elastic recovery of the board while absorbing the roughness of the joint surfaces on both the front and back sides of each sub-plate. The present invention provides a metal laminated gasket for engines. Hereinafter, details of the present invention will be explained using examples shown in the drawings.

FIG. 1 is a partially cutaway plan view showing one embodiment of the metal laminated gasket for internal combustion engines according to the present invention;
The figure is an enlarged cross-sectional view when FIG. 1 is cut along the - line. In these figures, the reference numeral 1 is a board made by punching out a hard and elastic thin metal plate such as SK or SUS into a shape that is the same as or similar to the joint surface. Around the bore 2, a single bead 3 having a height corresponding to the required surface pressure is placed around the cylinder bore 2.
It is provided so as to surround the cooling water passage 4 and the oil passage 5, which form the low-temperature part, and has a height corresponding to the required surface pressure so as to surround the cooling water passage 4 and the oil passage 5, respectively. A single bead 6, 7 is provided.

On the other hand, on both sides of the substrate 1, upper and lower sub-plates 8 and 9 made of hard metal plates such as iron plates are arranged in parallel. , cylinder bores 8a, 9a, cooling water passages 8b, 9b (reference numeral 9b is not shown), and oil passages 8c, 9c are provided corresponding to the cooling water passage 4 and the oil passage 5, respectively. Note that 10 is a bolt hole.

However, this alone has the drawbacks mentioned above. Therefore, in the present invention, a sealing material 11 made of soft rubber or heat-resistant resin is applied to the entire surface side a of the lower sub-plates 8 and 9, that is, the side that comes into direct contact with the cylinder head and cylinder block. Or print, and also print on the back side b, that is, the board 1
On the side that comes into contact with the cylinder bore 2, the cooling water passage 4, and the oil passage 5, a soft sealing material 11 is locally applied or printed in areas corresponding to the beads 3, 6, and 7 provided around the cylinder bore 2, cooling water passage 4, and oil passage 5. It is structured as follows. By having such a configuration,
The elastic restorability of the beads 3, 6, 7 of the substrate 1 is maintained by the hard upper and lower sub-plates 8, 9, and the elasticity of the upper and lower sub-plates 8, 9, cylinder head, cylinder block and substrate is maintained without any deterioration. It is possible to improve the adhesion with each bonding surface of 1, and therefore, the roughness of the bonding surface is reliably absorbed, which has the effect of improving the sealing performance. Furthermore, at this time, the beads 3, 6, 7 are formed on the back side b.
By not covering the sealing material 11 in areas other than the necessary areas corresponding to the area, deterioration of thermal conductivity can be suppressed. In addition, the lower sub-plates 8 and 9 may be plated with a soft metal such as aluminum or zinc, and this may be used as a sealing material.

As explained above, according to the metal laminated gasket for internal combustion engines according to the present invention, the entire surface side of each sub-plate and the area corresponding to the bead on the back side are coated with a soft sealing material. The elastic restorability of the substrate is maintained by the hard upper and lower sub-plates without any deterioration, and the roughness of each joint surface between the cylinder head, cylinder block, and bead formed on the substrate and the hard sub-plate is The soft sealing material coated on both the front and back sides of each sub-plate can reliably absorb the gas, especially from the bonding surface between the board and the hard sub-plate, which is created by forming beads on the board and configuring the gasket three-dimensionally. This has the practical effect of preventing leakage and improving sealing performance. In addition, by not covering the back side of each sub-plate with sealant, which can cause deterioration of thermal conductivity, except for the necessary areas in the area corresponding to the bead, deterioration of thermal conductivity can be suppressed as much as possible. can.

[Brief explanation of the drawing]

FIG. 1 is a partially cutaway plan view showing one embodiment of the metal laminated gasket for internal combustion engines according to the present invention;
The figure is an enlarged cross-sectional view when FIG. 1 is cut along the - line. 1-Substrate, 8-Upper sub-plate, 9-Lower sub-plate, 11-Sealing material.

Claims (1)

[Claims for Utility Model Registration] 1 Sub-plates made of hard metal plates are arranged on both sides of a substrate made of an elastic metal plate having beads, and the entire surface side of each sub-plate and the area corresponding to the bead on the back side of each sub-plate are provided. A metal laminated gasket for an internal combustion engine characterized by being coated with a soft sealing material to absorb the roughness of the joint surfaces on both the front and back surfaces of each sub-plate while maintaining thermal conductivity and elastic restorability of the substrate. . 2. The internal combustion engine according to claim 1, wherein a rubber material or heat-resistant resin is coated or printed on the entire surface side of the sub-plate and the region corresponding to the bead on the back side, and this is used as a sealing material. Metal laminated gasket for use. 3. A metal for an internal combustion engine according to claim 1, which is a utility model registration, in which the entire surface side of a sub-plate made of a hard material and the area corresponding to the bead on the back side are plated with a soft metal, and this is used as a sealing material. Laminated gasket.