JPH08200504A - Metal gasket - Google Patents

Abstract

PURPOSE: To facilitate the assembly work, to improve the yielding of the material in manufacturing the metallic sheet, and to reduce the weight by preventing a connecting part to connect laminated metallic sheets from being projected outside of the space between two sheets opposite to each other so as to keep the sealing. CONSTITUTION: A metal gasket consists of three laminated metallic sheets 5, 6. Connecting parts 10a are provided on a plurality of part of the respective metallic sheets 5, 6 at the parts located within the plane between two sheets opposite to each other so as to keep the sealing. These connecting parts 10a are formed by engaging first and second locking projecting parts 14a, 14b of the metallic sheets 5, 5 in connecting holes 13 of the metallic sheet 6. The thickness t1 of the connecting parts 10a is not greater than the total thickness of t2 of the laminated metallic sheets 5, 6.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The metal gasket according to the present invention can be used as, for example, Cylinder head gasket for sealing the abutting part between the engine cylinder block and the cylinder head. Exhaust manifold gasket for sealing the abutting part between the engine cylinder head side and the exhaust manifold. A gasket for sealing the abutting surface of the flange provided at the end of the exhaust pipe and the flange provided at the end of the silencer or catalytic converter.

[0002]

2. Description of the Related Art A cylinder head gasket is sandwiched between a lower surface (first flat surface) of a cylinder head and an upper surface (second flat surface) of a cylinder block of an internal combustion engine (not shown), It prevents high-pressure combustion gas generated inside, or cooling water or lubricating oil flowing between the cylinder block and the cylinder head from leaking to the outside. As such a cylinder head gasket, a metal cylinder head gasket formed by stacking a plurality of metal plates has been conventionally known.

FIG. 6 shows an example of such a metal cylinder head gasket. In this metal cylinder head gasket 1, circular bore holes 2 and 2 matching the opening shape of the cylinder top, small holes 3 and 3 through which bolts for fixing the cylinder head to the cylinder block are inserted, cooling water or lubricating oil. Through holes 4 and 4 for passing through are provided respectively.

In such a metal cylinder head gasket 1, conventionally, as shown in FIG. 8, a plurality of metal plates 5 and 6 (three in the illustrated example) such as galvanized steel plates and stainless steel plates are laminated. It is composed of. As shown in FIGS. 6 to 7, tongue-shaped protrusions 7 and 7 are formed at a plurality of locations on the outer peripheral edges of the plurality of metal plates 5 and 6, and in each of the protrusions 7 and 7, The plurality of metal plates 5 and 6 are joined together.

Conventionally, the protrusions 7, 7 are connected to each other by
As shown in FIGS. 6 to 8, the eyelet 8 was used. That is, through holes 9 are formed in the metal plates 5 and 6 in the protruding portion 7 so as to be aligned with each other. And each through hole 9,
The eyelet 8 which is inserted through 9 and caulked is used to form a joint portion to prevent the metal plates 5 and 6 from being separated from each other. Further, as shown in FIGS. 9 to 10, two pairs of cuts 11, 11 which are parallel and discontinuous to each other are formed in the protruding portion 7,
The front and back direction (up and down direction in FIG. 10) of the plurality of metal plates 5 and 6 that overlap each other between the two cut lines 11 and 11
In addition, a coupling portion 10 including locking protrusions 12 and 12 formed by swelling and plastically deforming in one movement by, for example, a pressing operation is also conventionally known.

[0006]

By the way, in the above-mentioned conventional coupling structure, the coupling portions are coupled to each other in order to prevent the coupling portions from interfering with the joint surfaces (the upper surface of the cylinder block and the lower surface of the cylinder head). Protruding portions 7, 7 projecting outward from the joining surface are formed at a plurality of outer peripheral edges of the plurality of metal plates 5, 6. Then, the protruding portions 7, 7
Eyelets 8 are provided on the inner surface or a connecting portion 10 is formed.
Therefore, the protrusions 7, 7 protrude outward in the plane direction from the edge of the joint surface between the cylinder head and the cylinder block. Therefore, there is a problem in that the degree of freedom in the arrangement of the above-mentioned auxiliary machines is restricted in order to avoid contact with the auxiliary machines arranged in a narrow engine room. Such inconvenience occurs not only in the above-mentioned case but also in the use of. In addition, the protrusions 7, 7
However, there is a problem to be improved in that the yield of the material of each metal plate 5 and 6 is poor and the weight is increased by the amount of the protrusions 7 and 7. The metal gasket of the present invention is
The invention was devised to solve the above problems.

[0007]

The metal gasket of the present invention, like the above-mentioned conventional metal gasket, is sandwiched between the first flat surface and the second flat surface facing each other, and the first flat surface and the second flat surface are opposed to each other. , Three or more metal plates each having a through hole for allowing fluid to pass therethrough to seal the abutting portion of the second flat surfaces are stacked on each other with the through holes of the respective metal plates aligned with each other. These metal plates are joined together and joined together.

In particular, in the metal gasket of the present invention, among the three or more metal plates, the intermediate metal plate located at the intermediate portion in the stacking direction is the above-mentioned first and second flat surfaces when used. The portion between the two is provided with a thinned portion formed by removing a part of the intermediate metal plate. or,
Of the three or more metal plates, the two surface metal plates located at both ends in the stacking direction are connected to each other by the connecting portion that engages the plastically deformed portions formed on the both surface metal plates themselves. Has been done. The thickness of the joint is set to be equal to or less than the total thickness of the three or more metal plates.

[0009]

In the metal gasket of the present invention constructed as described above, the connecting portion for connecting a plurality of metal plates does not project outward from between the two surfaces facing each other which are intended to hold the seal. The entire surface including the connecting portion is sandwiched in a plane between the first flat surface and the second flat surface.
Then, there is no gap between the two surfaces due to the joint portion, and the two flat end surfaces are completely brought into close contact with each other so that a seal is held between the two surfaces.

As described above, since the metal gasket of the present invention does not have a special projecting portion for forming the above-mentioned connecting portion, the degree of freedom in arranging parts around the assembly is increased,
Assembly of the entire device becomes easy.

[0011]

1 to 3 show a first embodiment of the present invention. It should be noted that the present embodiment and the second to third embodiments to be described later apply the present invention to a metal cylinder head gasket. Metal cylinder head gasket 1a
Is the same as the above-mentioned conventional metal cylinder head gasket except for the position and structure of the coupling portion 10a described later, and is formed by laminating a plurality of (three in this embodiment) metal plates 5, 6. And, it has circular bore holes 2 and 2 each of which is a through hole through which a fluid passes and which matches the opening shape of the cylinder top, and a plurality of through holes 4 and 4 through which cooling water or lubricating oil passes. . In addition, it is a member to be connected to each other,
It has a plurality of small holes 3 and 3 into which bolts for connecting the cylinder head and the cylinder block are inserted.

The above-mentioned three metal plates 5 and 6 laminated on each other.
Among them, the bore holes 2 and 2, the through holes 4 and 4, the small holes are provided at a plurality of positions located in the middle in the stacking direction (the vertical direction in FIG. 3) and partially near the outer periphery of the metal plate 6 which is an intermediate metal plate. A thin portion for accommodating a coupling portion 10a, which will be described later, is provided in a portion that does not interfere with any of the portions 3 and 3. In this embodiment, this thinned portion is formed by the rectangular coupling hole 13 which is a through hole.

The coupling holes 13 are formed in different directions (randomly). In this way, each coupling hole 1
The direction of 3 is made different by the force applied in the shearing direction due to the thermal expansion and contraction of the cylinder head associated with the repeated operation and stop of the engine, so that the plurality of metal plates 5 and 6 superposed on each other face each other. This is to prevent shifting in the direction.

A part of a pair of front and back metal plates 5 and 5, which are surface metal plates and are stacked on both sides of the intermediate metal plate 6 so as to sandwich the metal plate 6, respectively. The portion of the metal plate 6 facing the coupling hole 13 is pushed into the coupling hole 13 from the respective surfaces toward the inside of the coupling hole 13. Then, the metal plates 5 and 5 are partially brought into close contact with each other to form a connecting portion 10a for connecting the metal plates 5 and 6 to each other. Each of these coupling portions 10a is located in the coupling hole 13. The thickness t ₁ of each of the connecting portions 10a is smaller than the total thickness t ₂ of the three stacked metal plates 5 and 6 (t ₁ <t ₂ ). Therefore, each of the coupling portions 10a
Is immersed within the total thickness t _{2 of the} three metal plates 5 and 6.

The work of forming the respective connecting portions 10a by extruding the portions of the pair of metal plates 5 and 5 which are aligned with each other is performed as follows. First, two parallel cuts 11a, 11a are formed at a position where a part of the metal plate 5, 5 is aligned with the coupling hole 13 and are close to the longitudinal edge of the coupling hole 13. Then, the first portion having a convex cross section, which is a plastic deformation portion, is formed by extruding the portion between the cuts 11a and 11a from the respective surfaces of the metal plates 5 and 5 and swelling them out. A stop projection 14a and a second locking projection 14b having a concave cross section are formed, and both locking projections 14a and 14b are closely fitted to each other.
The fitting portion is the coupling portion 10a.

The operation of forming the connecting portions 10a is carried out in one movement by pressing with male and female forming dies having dimensions close to the shape of the connecting holes 13, and the cuts 11a and 11a are formed. At the same time as forming the above,
The second locking projections 14a and 14b are extruded and molded.
The pair of metal plates 5 and 5 are the first and second locking projections having the above-mentioned convex or concave cross-sectional shape with the intermediate metal plate 6 being aligned and sandwiched from both sides thereof. Part 1
The side walls 4a, 14b are frictionally engaged with each other by fitting the side walls 15a, 15b to each other so as not to be separated. As a result, the intermediate metal plate 6 sandwiched between the pair of metal plates 5 and 5 described above.
Can be handled integrally with both metal plates 5 and 5.

In the metal cylinder head gasket 1a of this embodiment constructed as described above, the upper surface of the cylinder block, which is the first flat surface, and the second flat surface, where the connecting portions 10a are formed, face each other. There is no outward projection from the abutting portion with the lower surface of the cylinder head, which is a surface, and the abutting portions facing each other are reliably sealed.

Next, FIG. 4 shows a second embodiment of the present invention. In this embodiment, the thinned portion is replaced with the coupling hole 13 (see FIGS. 1 to 3) in the above-described first embodiment, and is a notch 16 that is open to the outer peripheral edge of the intermediate metal plate 6.
Other configurations and operations are similar to those of the above-described first embodiment. In addition, in a single metal cylinder head gasket,
You may provide both the coupling hole 13 and the notch 16 which are each a meat removal part.

Next, FIG. 5 shows a third embodiment of the present invention. In the present embodiment, the thinned portion is a circular hole 1 which is a through hole.
It is formed by 7. In the case of the present embodiment configured to include such a circular hole 17, the connecting portion 10b of the metal plates 5 and 6 is formed.
Is a part of the pair of front and back metal plates 5, and is the intermediate metal plate 6
The portion opposed to the circular hole 17 formed in 1 is extruded into the circular hole 17 without forming a cut. That is, by plastically deforming each extruded part,
On each of the metal plates 5 and 5, there are formed circular tray-shaped locking projections 18 and 18a which are plastically deformable portions. Then, the two locking projections 18 and 18a are closely fitted to each other to form the coupling portion 10b. The cross-sectional shape of the connecting portion 10 across the diameter is the same as that of the first embodiment shown in FIG.

The metal plates 5 and 5 are connected to each other by frictional force between the outer peripheral surface of the locking projection 18 and the inner peripheral surface of the locking projection 18a which are fitted to each other. In the third embodiment shown in FIG. 5, since the connecting portion 10b is formed by the round tray-like locking protrusions 18 and 18a, the force in the shearing direction is equal to that in any direction. Can be received.

In each of the above-mentioned embodiments, each connecting portion 10
locking protrusions 14a, 14b, 18, which form a and 10b,
18a forming side, in other words, which metal plate 5
The locking projections 14a and 18 having a convex cross-section are formed on one side, and which metal plate 5 is to be formed with the locking projections 14b and 18a having a concave cross-section is unified on either the front or back side of the metal cylinder head gasket 1a. You may. However, the adjacent connecting portions 10
a, 10b, the locking protrusions 14a, 14b, 1
The metal plates 5 and 5 forming the plates 8 and 18a may be turned upside down. In this manner, the engaging projections 14a, 14b, 18, 18a are left in the pair of front and back metal plates 5, 5 by reversing the pushing directions of the locking projections 14a, 14b, 18, 18a between the adjacent coupling portions 10a, 10b. The difference in the tensile stress generated can be eliminated, and the warp of the metal cylinder head gasket 1a can be suppressed to be small.

Further, in each of the above-described embodiments, an example in which a plurality of metal plates 5 and 6 are superposed on each other while being in metal contact with each other has been described. However, in order to improve the sealing property, the surface of each metal plate 5 and 6 is improved. It is also possible to form a rubber coating layer having heat resistance.

Further, the shapes of the locking projections 14a, 14b, 18, 18a constituting the above-mentioned coupling portions 10a, 10b,
The locking structure for preventing separation is not limited to the above-mentioned embodiment, but can be appropriately implemented within the scope of the claims. or,
The number of metal plates to be laminated is also changed depending on usage conditions, and is not limited as long as it is three or more.

[0024]

Since the metal gasket of the present invention is constructed and operates as described above, the mounting work can be facilitated while the degree of coupling between the plurality of metal plates is secured. In addition, sufficient sealing performance can be exhibited without impairing the degree of freedom in arranging components around mounting. Further, in manufacturing the gasket itself, the yield of the used material is improved, and at the same time, the weight can be reduced.

[Brief description of drawings]

FIG. 1 is a partial plan view showing a first embodiment of the present invention.

FIG. 2 is an enlarged view of a portion A in FIG.

FIG. 3 is an enlarged BB sectional view of FIG.

FIG. 4 is a view similar to FIG. 2, showing a second embodiment of the present invention with a part cut away.

5 is a view similar to FIG. 2, showing a third embodiment of the present invention with a part cut away.

FIG. 6 is a partial plan view showing a conventional metal cylinder head gasket.

FIG. 7 is an enlarged view of part C in FIG.

8 is an enlarged cross-sectional view taken along the line DD of FIG.

FIG. 9 is a view similar to FIG. 7 showing a conventional coupling portion.

FIG. 10 is an enlarged EE sectional view of FIG.

[Explanation of symbols]

 1, 1a Metal cylinder head gasket 2 Bore hole 3 Small hole 4 Through hole 5, 6 Metal plate 7 Projection part 8 Eyelet 9 Through hole 10, 10a, 10b Coupling part 11, 11a Cut line 12 Locking projection part 13 Coupling hole 14a No. One locking projection 14b Second locking projection 15a, 15b Side wall 16 Notch 17 Circular hole 18, 18a Locking projection

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Fumio Kishi 1-5-2 Fukaminishi Yamato-shi, Kanagawa Nihon Lines Co., Ltd.

Claims (2)

[Claims] 1. A first flat surface and a second flat surface, which are opposed to each other, sandwiched between the first flat surface and the second flat surface. In the metal gasket, wherein three or more metal plates having through holes are overlapped with each other with the through holes of these metal plates aligned, and the metal plates are joined together. The intermediate metal plate located in the middle portion in the stacking direction among the one or more metal plates is partially removed from the intermediate metal plate at a portion located between the first and second flat surfaces during use. Among the above three or more metal plates, two surface metal plates located at both ends in the stacking direction are provided with a thinned portion formed by performing plastic deformation formed on these both surface metal plates themselves. Are connected to each other by a connecting part that engages the parts The metal gasket is characterized in that the thickness of the joint is less than the total thickness of the three or more metal plates. 2. The thinned portion is at least one of a notch formed in an outer peripheral edge portion of the intermediate metal plate and a through hole formed in an inner portion of the intermediate metal plate. The listed metal gasket.