JPH0643576Y2 - Metal gasket - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to a metal gasket used for sealing a joint surface between a cylinder head and a cylinder block of an internal combustion engine, particularly a multi-cylinder internal combustion engine, and more specifically, a cylinder. The present invention relates to a metal gasket in which a grommet substrate is laminated on a bead substrate made of an elastic metal plate in which beads are formed in a contour shape along each peripheral edge of an opening for a bore with or without an adjustment plate.

(Prior Art) As shown in FIG. 8, for example, a metal gasket of this type is adjusted to a bead substrate 3 made of an elastic metal plate in which an inward bead 2 is formed along the periphery of an opening 1 for a cylinder bore. By stacking the plate 4 and the grommet substrate 5 and folding back the inner peripheral edge of the grommet substrate 5 to enclose the bead substrate 3 and the inner peripheral edge of the adjusting plate 4 to form the grommet portion 6a,
The grommet portion 6a is provided with a stopper function for the bead 2 to reduce the stress on the bead portion.

(Problems to be solved by the invention) However, in the above-described conventional metal gasket, the thickness of the grommet portion 6a is such that the grommet substrate 5, the adjusting plate 4, and the bead substrate 3 are formed over the entire circumference of the opening 1 for the cylinder bore. There is a problem in that it is not possible to adjust the surface pressure distribution corresponding to different rigidity occurring at the peripheral edge of the cylinder bore opening 1 because the thickness becomes constant due to the above and the spring characteristics cannot be expected.

Further, if the grommet substrate 5 is thickened to adjust the surface pressure distribution, the spring characteristics of the grommet portion 6a can be improved to some extent, but the surface pressure is concentrated on the grommet portion 6a (the stopper function is too hard). There is a problem in that the spring characteristics of the bead 2 cannot be fully utilized and the function as a gasket cannot be exhibited.

Further, if the grommet substrate 5 is made thin, its strength becomes weak and cracks are easily generated in the grommet portion 6a, which causes a problem in durability.

(Purpose of the invention) The present invention exhibits excellent spring characteristics in the grommet part,
A metal that can be adjusted finely over a wide range without changing the thickness of the grommet substrate to adjust the surface pressure according to the engine head rigidity, and can secure excellent sealing performance by two-step surface pressure. Intended to provide gaskets.

(Means for Solving the Problem) Means for achieving the above-mentioned object are as follows: a bead substrate 3 made of an elastic metal plate having beads 2 formed along the peripheral edge of each of the parallel cylinder bore openings 1 and an adjusting plate 4; In the metal gasket in which the grommet substrate 5 is laminated with or without the interposition, and the inner edge portion along the cylinder opening 1 of the grommet substrate 5 is folded back to form the grommet portion 6, the inner periphery of the folded back grommet portion 6 In addition, the corrugated spring plate 7 is formed in a ring shape so that the peaks are formed in a radial direction from the center of the opening 1 for the cylinder bore and intersect the peripheral edge thereof.

(Example) The structure of the metal gasket according to the present invention will be described based on an example.

FIG. 1 is a partial plan view of a metal gasket G showing a first embodiment of the present invention, FIG. 2 is an enlarged sectional view taken along the line II of FIG. 1, and FIG. 3 is a corrugated spring plate used for a grommet portion. 4 is a partial front view of FIG. 4, and FIG. 4 is a sectional view taken along line II-II of FIG.
5 to 7 show another embodiment, which is II of FIG.
It is an expanded sectional view in a line.

In any of the embodiments, a wavy spring plate 7 is formed in a ring shape around the inside of the grommet portion 6 formed by folding back the grommet substrate 5 and in which the crests are formed in the direction intersecting the peripheral edge of the opening 1 for the cylinder bore. The grommet portion 6 has excellent spring characteristics, and excellent sealing performance due to the two-step surface pressure with the bead 2 is secured.

First, the first embodiment shown in FIGS. 1 to 4 is a bead substrate 3 made of an elastic metal plate having beads 2 formed along the respective peripheral edges of the parallel cylinder bore openings 1.
An adjusting plate 4 having an opening diameter D1 for the cylinder bore larger than the opening diameter D2 for the cylinder bore of the bead substrate 3 is laminated on the inner surface so that the bead 2 becomes the outer surface, and the inner circumference of the hole of the adjusting plate 4 is laminated. The inner peripheral edge 8 of the bead substrate 3 is extended to the inner side of the inner peripheral edge 8, and the peaks are formed on the inner surface side of the inner peripheral edge 8 in a direction radiating from the center of the opening 1 for the cylinder bore and intersecting the peripheral edge. Spot welding the plate 7,
It is fixed by arc welding, laser welding, brazing means, etc., the grommet substrate 5 is further laminated on the adjusting plate 4, and the inner peripheral edge of the cylinder bore opening 1 is folded back and fixed to the inner peripheral edge 8 of the bead substrate 3 and this. The corrugated spring plate 7 is wrapped around to form the grommet portion 6.

The metal gasket according to the second embodiment shown in FIG.
Although the adjusting plate 4 is interposed as in the first embodiment, a step 9 is provided on the inner peripheral edge 8 of the bead substrate 3 so as to be in close contact with the grommet substrate 5 on the same surface as the adjusting plate 4. The corrugated spring plate 7 is fixed to the outer side of the inner peripheral edge 8, and the inner peripheral edge 8 and the corrugated spring plate 7 are enclosed by the grommet substrate 5 to form the grommet portion 6.

Further, the metal gasket according to the third embodiment shown in FIG. 6 does not use the adjusting plate 4 but is composed of the bead substrate 3 and the grommet substrate 5, and the bead substrate 3 is laminated on the grommet substrate 5. At the same time, the corrugated spring plate 7 is fixed to the inner peripheral side of the inner peripheral edge 8 of the bead substrate 3,
By folding back, the corrugated spring plate 7 and a part of the inner peripheral edge 8 are wrapped to form the grommet portion 6.

Furthermore, the metal gasket according to the fourth embodiment shown in FIG. 7 does not use the adjusting plate 4 as in the third embodiment, and the inner peripheral edge 8 of the bead substrate 3 on the surface where the bead 2 bulges. The corrugated spring plate 7 is fixed to the corrugated spring plate 7 and the grommet substrate 5 is laminated on the surface where the bead 2 swells.
And the inner peripheral edge 8 of the bead substrate 3 is wrapped around the grommet substrate 5 to form the grommet portion 6.

In addition, in each of the examples, the description has been made on the assumption that the plate thickness of the corrugated spring plate 7 is constant, but in addition to the above examples,
As shown in FIG. 1, the peripheral portion of the cylinder bore opening 1 is thick at the positions corresponding to the portions A and C, and is thin at the portion corresponding to the portion B, and the positions between A and B and between B and C are slightly increased. It is also included in the case of forming a gradually changing part of or changing the spring constant by changing the wave pitch, height, etc. of the corrugated spring plate 7.

This is because the cylinder head is generally made of aluminum and has low rigidity, so that it corresponds to the deflection of the head when a metal gasket is inserted and tightened with bolts, and almost the same surface pressure can be obtained at any position on the circumference. This is to improve the sealing performance.

(Advantageous Effects of the Invention) The present invention provides a grommet substrate with or without an adjustment plate 4 on or from a bead substrate 3 made of an elastic metal plate having beads 2 formed along the respective peripheral edges of the parallel cylinder bore openings 1. 5 are laminated, and the inner edge portion along the cylinder opening 1 of the grommet substrate 5 is folded back to form the grommet portion 6
In the metal gasket formed with, the corrugated spring plate 7 is formed around the inside of the folded back grommet portion 6 so that the peaks are formed in a direction that radiates from the center of the opening 1 for the cylinder bore and intersects the peripheral edge thereof. Therefore, excellent spring characteristics can be obtained in the grommet portion 6, and a two-step surface pressure structure in which the surface pressure of the grommet portion 6 and the bead portion can be easily balanced is obtained, and the sealing characteristics can be remarkably improved, and the engine can be significantly improved. Since the head can follow the movement of the head during operation, the sealing performance can be improved also from this aspect.

Further, it becomes possible to selectively use a high-strength material for the corrugated spring plate 7, and moreover, the corrugated spring plate 7 has a thickness, a wave height, and
Since it is easy to appropriately change the pitch and the like, it is possible to provide a metal gasket having an extremely high degree of freedom in design, an effect of preventing fatigue and a stable spring characteristic.

Further, since it is not necessary to change the thickness of the grommet substrate 5 for adjusting the surface pressure distribution, there is no occurrence of surface pressure concentration or cracks due to the change of the grommet substrate for adjusting the surface pressure distribution as in the conventional case. In addition, a proper stopper function can be ensured, the spring characteristics of the bead portion can be fully utilized, a sufficient function as a gasket can be exerted, and durability can be improved.

[Brief description of drawings]

FIG. 1 is a partial plan view of a metal gasket G showing a first embodiment of the present invention, FIG. 2 is an enlarged sectional view taken along the line II of FIG. 1, and FIG. 3 is a corrugated spring plate used for a grommet portion. 4 is a partial front view of FIG. 4, and FIG. 4 is a sectional view taken along line II-II of FIG.
5 to 7 show another embodiment, which is II of FIG.
8 is an enlarged sectional view taken along the line, and FIG. 8 is an enlarged sectional view taken along the line II of FIG. 1 of the conventional metal laminated gasket. 1 ... Opening for cylinder bore 2 ... Bead, 3 ... Bead substrate 4 ... Adjustment plate, 5 ... Grommet substrate 6 ... Grommet part, 7 ... Corrugated spring plate 8 ... Inner peripheral edge, 9 ... Step

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Naoki Ii, 248 Kano, Higashiosaka, Osaka Prefecture, Japan Gasket Co., Ltd. (72) Inventor, Kunitoshi Inoue, 248, Kano, Higashiosaka, Osaka Stocks, Nippon Gasket In-house (56) Reference JP 1-73157 (JP, A) JP 1-58868 (JP, A) Actual Kai 1-173570 (JP, U) Actual Kai 1-165366 (JP, U) ) Actually open 62-163661 (JP, U) Actually open 59-86344 (JP, U) Actually open 59-135354 (JP, U) Actually open 57-193948 (JP, U)

Claims (2)

[Scope of utility model registration request] 1. A grommet substrate 5 is laminated with or without an adjusting plate 4 on a bead substrate 3 made of an elastic metal plate on which beads 2 are formed along the respective peripheral edges of parallel cylinder bore openings 1. In the metal gasket in which the grommet portion 6 is formed by folding back the inner edge portion along the cylinder opening portion 1 of the grommet substrate 5, peaks are radiated from the center of the cylinder bore opening portion 1 around the inside of the folded back grommet portion 6. The metal gasket is characterized in that the corrugated spring plate 7 formed in a direction intersecting the peripheral edge thereof is arranged in a ring shape. 2. The metal gasket according to claim 1, wherein the spring characteristics are changed by changing the thickness, pitch, height, etc. of the corrugated spring plate 7 in accordance with the rigidity of the peripheral edge of the opening 1 for the cylinder bore.