JP2001336638A - Cylinder head gasket - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cylinder head gasket for a multi-cylinder water-cooled engine, of such a structure that the base board interposed between each cylinder block and cylinder head is coupled with a stopper plate by means of simultaneous caulking, the caulking operation being able to be conducted even to a hard- to-access part, wherein it is practicable to prevent laminate plates from slipping off likely caused by simultaneous caulking. SOLUTION: An overhang 14 protruding from the periphery of a stopper plate 4 is formed on the cylinder head gasket 1 in its part avoiding a squeezing hole 7 for cooling water, and to the position straddling the forefront of the overhang 14, a rectangular swellout 5 is formed by means of simultaneous pressing with all base boards 2 and 3 laminated using a specified die for molding, and the longer edges 5a--on both sides of the swellout 5 are punched off with notches 21 left while the shorter edges 5b--on both sides of the swellout 5 are formed bending with no notch provided, and thereby slipping-off is prevented by the mutually resisting force of the notches at the swellout longer edges 5a--.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cylinder head gasket in which a substrate and a stopper plate interposed between mating surfaces of a cylinder head and a cylinder block of a multi-cylinder water-cooled engine are simultaneously caulked. is there.

[0002]

2. Description of the Related Art Conventionally, a cylinder head gasket has been sandwiched between mating surfaces of a cylinder head and a cylinder block of an internal combustion engine, so that high-pressure combustion gas generated in a cylinder or a cylinder head and a cylinder block have been combined. Cooling water and lubricating oil flowing between the surfaces are prevented from leaking to the outside.

In such an internal combustion engine, a cylinder head gasket sandwiched between these mating surfaces is fixed at a fixed position by bolting a cylinder head to a cylinder block. In the vicinity of the outer periphery of the cylinder bore, the tightening load of the bolt is reduced, so that a gap is formed between the mating surfaces of the cylinder head and the cylinder block, and there is an inconvenience that the combustion gas flows through the gap.

Therefore, in order to prevent such a blow-by of the combustion gas, a bead surrounding the cylinder bore is formed on the substrate of the cylinder head gasket to improve the sealing performance.

[0005] However, when the bead is hit between the mating surfaces of the cylinder head and the cylinder block during the combustion explosion in the cylinder bore, the bead is bent, and the initial sealing performance is reduced due to aging, and the combustion gas is discharged. There is a problem that it is not possible to sufficiently prevent blow-through.

In order to solve such a problem, FIG.
As shown in FIG. 1, a stopper plate 44 surrounding a cylinder bore 33 is provided on substrates 41 and 42 constituting a cylinder head gasket 40.

The cylinder head gasket 4 shown in FIG.
Reference numeral 0 indicates that two hard substrates 41 and 42 are laminated, and on each of the substrates 41 and 42, bore beads 45a and 45b having an arc-shaped cross section surrounding the cylinder bore 33 are formed with their tops facing each other. Step beads 46a, 46b are formed on the outer periphery from the bead forming position of FIG. 3, and a stopper plate 44 is overlapped on the outer periphery of the cylinder bore 33 along the upper surface of the lower substrate 42. Thus, a bore bead 45c and a step bead 465c are formed.

On the outer periphery of the stopper plate 44, a partial projecting portion 47 is formed at a position corresponding to the cooling water passage 34 formed in the cylinder block 32, and the projecting portion 47 has a circular projecting portion. The stopper plate 44 is connected to the lower substrate 42 by forming a blind stop 48 in a shape of a circle and by caulking with the perforated portion 49 of the lower substrate 42.
Of the cylinder block 32 is accommodated in the cooling water passage 34 of the cylinder block 32.

A cylinder head gasket 50 shown in FIG. 11 includes an upper substrate 51, a middle substrate 52, and a lower substrate 53.
And an upper substrate 51 and a middle substrate 52
Are formed so that the tops of the bore beads 54a and 54b having an arc-shaped cross section surrounding the cylinder bore 33 face each other.
Step beads 55a, 5a
5b are formed, and a stopper plate 56 is overlapped on the outer periphery of the cylinder bore 33 along the lower surface of the middle substrate 52.

The stopper plate 56 has a middle substrate 5
2, a bead 54c and a step bead 55d are formed, and a partial overhang 57 is formed on the outer periphery of the stopper plate 56. A burring 58 formed on the overhang 57 is formed by punching the middle substrate 52. And a burring 5 in the perforated portion 51a of the upper substrate 51.
8 to accommodate the projecting end 58a.

Further, the cylinder head gasket 5
0, the bead 54 c is provided below the middle substrate 52.
The stopper plate 56 is sandwiched by laminating the lower substrates 53 on which are formed.

By the way, the stopper plate 44,
According to the coupling method of 56, the stopper plates 44, 56
It is possible to perform a firm connection between the stacked substrates and the substrates 41 and 42, but it is necessary to bond the stacked substrates at other positions with rivets or the like.

Therefore, in order to integrally connect the laminated plate materials of the cylinder head gasket, the number of steps is increased, such as connecting the stopper plate and the substrate, and further connecting the laminated substrates, thereby increasing the cost. There was also a problem of becoming.

Further, in the case of performing the crimping by the blind stop 48 or the burring 58, the projecting portion 47 or 57 of the stopper plate 44 or 56 needs a space around the entire circumference of the crimping portion. The area of the projecting portion 47 or 57 becomes large, and there is no room for the cooling water throttle hole 39 formed in the cylinder head gasket, for example.
The overhang 47 or 57 may interfere with the cooling water throttle hole 39.

[0015]

In order to solve such a problem, a cylinder head gasket 60 shown in FIGS. 12 and 13 has been developed. The cylinder head gasket 60 is formed by simultaneously caulking the stacked substrates 61 and 62 and the stopper plate 63.

The cylinder block 32 shown in FIG. 12 is of an open deck type, and a cooling water passage 34 is continuously provided around a cylinder bore 33.
The flow rate of the cooling water from the cooling water passage 34 on the side to the cooling water passage on the cylinder head side is controlled by the upper and lower substrates 61, 62.
In order to adjust the inner diameter of the cooling water throttle hole 64, the periphery of the cooling water hole 64 is exposed to the cooling water passage 34 on the cylinder block 32 side.

Such a cylinder head gasket 60
As shown in FIG. 13, a stopper plate 63 surrounding the cylinder bore 33 is superposed on the lower surface of the upper substrate 61 of the two hard substrates 61 and 62, and the stopper plate 63
The lower substrate 62 is laminated on the lower side. The stopper plate 63 has a width extending from around the cylinder bore 33 to the inside of the cooling water passage 34.
Cooling water throttle holes 64 of the upper and lower substrates 61 and 62
A protrusion 66 is formed between the protrusions 64.

Each of the substrates 61 and 62 has an arc-shaped bore bead 67a or 6a surrounding the cylinder bore 33.
7b, the upper substrate 6 is also provided on the stopper plate 63.
A bobbin 67c corresponding to one bobbin 67a is formed.

As a method of simultaneously caulking the stopper plate 63 and the upper and lower substrates 61 and 62,
As shown in FIG. 12, the upper and lower substrates 6 are located at locations other than the cooling water throttle holes 64 of the cylinder head gasket 60.
Simultaneous caulking is performed on the projecting parts 66 of the stopper plate 63 by using a molding die having a rectangular molding surface, and the bulging part 68 caused by the caulking is fixed to the cylinder block 32 of the open deck (or the cylinder of the closed deck). The head is accommodated in the cooling water passage 34 so as to avoid interference with the deck surface.

By the way, in such a conventional caulking connection, the bulging portion 68 is formed in the plane of the overhanging portion 66. Even in this simultaneous caulking, a space 69 is required around the bulging portion 68. However, since the width of the cooling water passage 34 in the cylinder head 31 and the cylinder block 32 and the clearance between the adjacent cooling water throttle holes 64, 64 are limited, the space 69 for the bulging portion 68 is cooled. There is a problem of interference with the deck surface of the cylinder block 32 outside the water passage 34 (interference width D).

As shown in FIG. 13, the bulging portion 68 is punched out by forming a cut at both long sides 68a, 68a of the bulging portion 68 by a molding die having a rectangular molding surface. It is formed by bending both short sides 68a, 68a without a cut.

Therefore, looking at the cross-sectional state along the line ZZ in FIG. 12, as shown in FIG. 13, the long sides 68a, 68a on both sides of the bulging portion 68 form a cut, and the cooling water of the cylinder block 32 is formed. Although it protrudes toward the passage 34, the bulged portion 68 is formed leaving a space 69 in the protruded portion 66, and the bulged portion 68 is disposed between the upper substrate 61 and the stopper plate 63 between the long sides 68a, 68a on both sides. There is a problem that the laminated board with the side substrate 62 is arranged in parallel with each other, the cut 71 on the side of the bulging portion 68 has a low resistance to the outer cut 72, and each of the laminated boards is pulled out. There was a point.

The present invention has been made in order to solve the above-mentioned problems, and a substrate interposed between a cylinder block and a cylinder head of a multi-cylinder water-cooled engine and a stopper plate are simultaneously coupled by caulking. It is an object of the present invention to provide a cylinder head gasket capable of performing simultaneous caulking even on a narrow portion and preventing the laminated plate material from being pulled out by simultaneous caulking.

[0024]

In order to solve the above-mentioned problems, a cylinder head gasket according to the present invention is provided with two or more cylinder head gaskets inserted into a mating surface of a cylinder head and a cylinder block in a multi-cylinder water-cooled engine. A stopper plate sandwiched between these substrates is formed of a continuous ring shape which is softer than the substrates and has a width extending from around each cylinder bore to the inside of the cooling water passage. In a cylinder head gasket in which a rectangular bulge formed by simultaneous crimping for integrally connecting all substrates and the stopper plate is formed to project into a cooling water passage around a cylinder bore of the cylinder head or the cylinder block. The stopper press at the location of the cylinder head gasket that avoids the cooling water throttle hole. The rectangular bulge is formed by forming a bulge protruding from the outer periphery of the bulge and simultaneously pressing all the laminated substrates with a predetermined molding die against a position straddling the tip of the bulge. Is formed, the long sides on both sides of the bulging portion are punched with cuts, and the short sides on both sides of the bulging portion are bent and formed without the cuts, thereby forming the long sides on both sides of the bulging portion. It is characterized in that the pull-out is prevented by the mutual resistance of the cuts of each plate material.

According to a second aspect of the present invention, there is provided a cylinder head gasket according to the first aspect, wherein the predetermined mold for forming the bulging portion includes a female mold and a male mold having a rectangular molding surface. The female mold has long sides on both sides and short sides on both sides,
One side of the male mold corresponds to the inner diameter of the short side on both sides of the female mold to form a cutout on both long sides of the bulging portion, and the other side of the male mold has both sides of the female mold. The bulge is formed on both short sides on both sides of the bulging portion with an inner diameter narrower than the side.

According to a third aspect of the present invention, there is provided a cylinder head gasket according to the first aspect, wherein the bulging portion is formed such that long sides on both sides thereof extend in a direction along the outer periphery of the cylinder bore. A side is formed along the radial direction of the cylinder bore, and the tip of the projecting portion of the stopper plate is received in the middle of both short sides of the bulging portion.

Further, in the cylinder head gasket of claim 4 according to the present invention, while the rubber sealing material is applied to the substrate surface, the cylinder head gasket may be provided between both short sides of the molding surface of the female mold of the molding die. By forming a parallel recess along the long side and using the female mold for the simultaneous caulking, a fold is formed near the cut on both long sides of the bulge, and the bulge is formed by the fold. A partial increase in surface pressure near the notch on the long side of both sides to enhance the resistance of pull-out prevention.

[0028]

Embodiments of the present invention will be described below with reference to the drawings.

According to the present invention, a cylinder head gasket is inserted between mating surfaces of a cylinder head and a cylinder block in a multi-cylinder water-cooled engine. As shown in FIG. The stopper plates 4 sandwiched between the substrates 2 and 3 are softer than the substrates 2 and 3 and, for example, as shown in FIG. It is formed in a continuous ring shape (see FIG. 1) having a width reaching the inside of the cooling water passage 34.

Further, in the present invention, as shown in FIG. 2 (or FIG. 7), all the laminated substrates, for example, the substrate 2,
3 and stopper plate 4
The cylinder head gasket 1 is provided with an overhanging portion 14 protruding from the outer periphery of the stopper plate 4 at a position avoiding the cooling water throttle holes 7, 7,.
To form a rectangular bulging portion 5 by simultaneous caulking, and project the bulging portion 5 into the cooling water passage 34 of the cylinder head 31 (see FIG. 3) or the cylinder block 32 to interfere with the deck surface. Try to avoid.

In FIG. 1, the cylinder head gasket 1 has an inner diameter for adjusting the flow rate of cooling water at a position corresponding to the cooling water passage 34 (see FIG. 2) of the cylinder block 32 on the outer periphery of the cylinder holes 6, 6,. .. Are formed in a required number, and oil holes 8, 8... And bolt holes 9, 9 are provided at predetermined positions near the outer periphery of the cylinder head gasket 1.
... are formed.

Hereinafter, a description will be given of a first embodiment in which the present invention is applied to an open deck type multi-cylinder water-cooled engine, and a second embodiment in which the present invention is applied to a closed deck type multi-cylinder water-cooled engine.

(Embodiment 1) As shown in FIG. 2, a cylinder head gasket 1 of this embodiment
Are interposed between a cylinder head 31 (see FIG. 3) and a cylinder block 32 of an open deck type multi-cylinder water-cooled engine in which a cooling water passage 34 is formed surrounding each of the cylinder bores 33, 33,. It was done.

In this cylinder head gasket 1, the upper substrate 2 and the lower substrate 3 constituting the two substrates 2, 3 are each made of a hard metal plate such as a SUS hard steel plate, and as shown in FIG. A plurality of cylinder holes 6, 6,... Are formed according to the cylinders of the water-cooled engine.

As shown in FIG. 2, the upper substrate 2 and the lower substrate 3 are provided with arc-shaped bore beads 10a, 10b at the same positions surrounding the cylinder holes 6, 6,. The outer peripheral beads 11a and 11b having a step shape are formed along the outer periphery of the upper substrate 2 and the lower substrate 3 in a protruding state (see FIG. 3).

Further, as shown in FIG. 3, both surfaces of the upper substrate 2 and the lower substrate 3 are covered with a rubber sealing material 12, respectively.

In order to form the upper and lower substrates 2 and 3, a SUS hard steel plate having a rubber sealing material 12 on both surfaces of the upper substrate 2 or the lower substrate 3 is stamped into a predetermined gasket shape. Alternatively, it is formed by stamping a SUS hard steel plate into a gasket shape, and then applying a rubber sealing material 12 on both surfaces.

Further, the stopper plate 4 is connected to the substrates 2, 3
A continuous ring shape that is softer and has a width extending from around each cylinder bore 33 to the inside of the cooling water passage 34 (FIG. 1)
Reference).

As shown in FIG. 2 or FIG. 3, the stopper plate 4 is superimposed on the lower surface of the upper substrate 2 to form a boad 10c having the same shape as the boad 10a formed on the upper substrate 2. On the outer periphery of the stopper plate 4, a projecting portion 14 is formed so as to protrude from the cylinder head gasket 1 at a position avoiding the cooling water throttle holes 7, 7,.

In the present invention, simultaneous caulking is used as a method for collectively connecting the stopper plate 4 to all the other substrates 2 and 3. The position where this caulking connection is performed is a position across the tip of the overhang portion 14 of the stopper plate 4.

That is, as shown in FIGS. 5 (a) and 5 (b), the molding die 15 for performing simultaneous caulking in this embodiment comprises a female die 16 and a male die 17 having a rectangular molding surface. , Female type 16
Has long sides 16a, 16a on both sides and short sides 16b, 16b on both sides. As shown in FIG.
The punching is performed on the material to be formed corresponding to the inner diameter of the short sides 16b on both sides of the female mold 16, and the other side 17a of the male mold 17 is formed on both sides of the female mold 16 as shown in FIG. The material to be formed is formed to be bent with an inner diameter narrower than the long side 16a.

As shown in FIG. 5 (a), a damper spring 18 is provided at the lower part of the female die 16 and, as shown in FIG. Is provided via a spring 20.

The female mold 16 and the male mold 17 of the molding die 15 described above.
By using the cooling water throttle holes 7 of the laminated plates 2, 3, 4 with the stopper plate 4 sandwiched between the upper and lower substrates 2, 3,
When press forming is simultaneously performed on the position avoiding 7 and straddling the tip of the protrusion 14 of the stopper plate 4, a rectangular bulge 5 is formed at the pressed position, and the bulge is formed. The long sides 5a, 5a of both sides of the swelling 5 are punched out to form a cut 21, and the short sides 5b, 5b of both sides of the bulging portion 5 are bent without a cut.

In this embodiment, as shown in FIG. 3, the swelling portion 5 has long sides 5a, 5a on both sides thereof extending in the direction along the outer periphery of each cylinder bore 33. The sides 5b, 5b are formed along the radial direction of each cylinder bore 33, and both short sides 5b, 5b
The above-described press molding is performed such that the tip of the overhang portion 14 of the stopper plate 4 is received in the middle of the process.

According to the above-described molding method, as shown in FIG.
Fits between the long sides 5a, 5a on both sides of the bulging portion 5, and the bulging portion 1
4 and the portion D where the overhang portion 14 does not exist.
Divided into two.

Further, in the present embodiment, the rubber sealing material 12 is applied to both surfaces of the upper and lower substrates 2 and 3, while FIG.
As shown in (a) and (b), a concave portion 23 parallel to the long side 16a is formed between the short sides 16b on both sides of the molding surface of the female mold 16 of the molding die 15 along the long side 16a.

When this female mold 16 is used for the above-mentioned simultaneous caulking, as shown in FIG.
And the pressing force P on the side D2 where the overhang portion 14 does not exist.
Are different (F> P), the side D where the overhang portion 14 is present
1, the rubber sealing material 12, which forms the cushion of the upper and lower substrates 2 and 3, is crushed by the pressing force F, so that the concave portion 23 of the female die 16 and the side D where the overhang portion 14 does not exist.
As the laminates 2, 14, 3 of the bulging portion 5 bend in the direction of the gap 25, the folds 24, 24 which partially increase the surface pressure near the cuts 21, 21 on both short sides 5a, 5a are formed. The folds 24 are formed on the laminates 2, 1 of the bulging portion 5 by providing resistance to the cuts 22 on both sides outside the bulging portion 5.
4 and 3 are prevented from slipping out.

(Embodiment 2) This embodiment is a specific example of a cylinder head gasket 1 applied to a closed deck type multi-cylinder water-cooled engine.
7 to 9 is the same as that of the first embodiment, and a tension member protruding from the outer periphery of the stopper plate 4 at a portion of the cylinder head gasket 1 other than the cooling water throttle holes 7, 7,... A rectangular bulge 5 is formed by forming the protrusion 14 and simultaneously pressing all the substrates 2 and 3 stacked with a predetermined molding die against a position straddling the tip of the protrusion 14. ing.

However, the bulging portion 5 of this embodiment is an example formed on the side of the cylinder head 31 of the closed-deck type multi-cylinder water-cooled engine that fits in the cooling water passage 34, and is shown in FIGS. As described above, the bulging portion 5 is formed so as to protrude to the opposite side to the bulging portion 5 of the first embodiment, and the molding direction for this also corresponds to it.

As shown in FIG. 8, the stopper plate 4 is overlapped along the upper surface of the lower substrate 2 unlike the case of the first embodiment.
In the same manner as described above, the state is sandwiched between the upper and lower substrates 2 and 3.

Therefore, also in this embodiment, the long sides 5a, 5a on both sides of the bulging portion 5 are formed by the cuts 2 as in the first embodiment.
1 and the short sides 5 on both sides of the bulging portion 5
b, 5b are formed without a cut, so that the cut 21 of each laminated plate and the cut 22 on the outer side of the cut 21 on the long sides 5a, 5a on both sides of the bulge 5 are formed by the mutual resistance. Of each of the laminated plates 2, 3, and 4 can be prevented.

Also in this embodiment, as shown in FIG. 7, the bulging portion 5 has long sides 5a on both sides thereof formed in a direction along the outer periphery of each cylinder bore 33. Both short sides 5b, 5b are formed along the radial direction of each cylinder bore 33, and both short sides 5b,
The above-described pressing is performed such that the tip of the overhang portion 14 of the stopper plate 4 is received in the middle of 5b.

Therefore, also in this embodiment, the overhang portion 14 is provided.
A portion D1 where the protrusion 14 exists and a portion D2 where the overhang portion 14 does not exist
The rubber sealing material 12 is applied to both surfaces of the upper and lower substrates 2 and 3, while the short side 16 b of both sides of the molding surface of the female mold 16 of the molding die 15 is parallel along the long side 16 a. When this female mold 16 is used for the above-mentioned simultaneous crimping, a cushion of the upper and lower substrates 2 and 3 is formed on the side D1 where the overhang portion 14 exists in the opposite direction of FIG. When the rubber sealing material 12 is crushed by the pressing force F, the laminated plates 2, 14, 3 of the bulging portion 5 move in the direction of the gap 25 between the concave portion 23 of the female die 16 and the side D <b> 2 where the protruding portion 14 does not exist. Folded shapes 24, 24 are formed near the cuts 21, 21 of the short sides 5a, 5a on both sides to form a partial surface pressure increase.
The folds 24 are formed on both side cuts 2 outside the bulging portion 5.
2, the laminates 2, 14,
3 is prevented from slipping out.

[0054]

As described above, in the cylinder head gasket of the present invention, a projection projecting from the outer periphery of the stopper plate is formed at a portion of the cylinder head gasket other than the cooling water throttle hole, and the projection is formed. A rectangular bulge is formed by simultaneously pressing all the substrates stacked with a predetermined molding die against a position straddling the tip of the bulge, and long sides on both sides of the bulge have cuts. Since the both short sides of the bulging portion are bent and formed without the cuts while being punched out, it is possible to prevent the bulging portion from being pulled out by the mutual resistance of the nicks of each plate material at the long sides on both sides of the bulging portion. Becomes

In the present invention, while a rubber sealing material is applied to the upper and lower substrate surfaces, a parallel concave portion is formed along the long side between short sides on both sides of the molding surface of the female mold of the molding die. When performing simultaneous caulking using a female mold, the pressing pressure on the side where the overhang is present is greater than the pressing pressure on the side where the overhang does not exist. When the rubber sealing material forming the cushion of the side substrate is crushed, the laminated plate of the bulging portion is bent in the gap direction on the side where the female concave portion and the protruding portion do not exist, and the short sides of both sides of the bulging portion are bent. A fold is formed in the vicinity of the cut, and the fold forms a resistance to the cuts on both sides outside the bulge, so that the swell of the bulge can be prevented from coming off.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view of a cylinder head gasket according to the present invention.

FIG. 2 is a partial perspective view showing an example in which the cylinder head gasket according to the first embodiment of the present invention is applied to an open deck type multi-cylinder water-cooled engine.

FIG. 3 is a sectional view taken along line AA of FIG. 2;

FIG. 4 is a sectional view taken along line BB of FIG. 2;

5 (a) is a view of the molding die according to the present invention as viewed from a side corresponding to a cross section taken along line AA of FIG. 2, and FIG. 5 (b) is a view of FIG.
It is the figure seen from the side corresponding to the B line section.

6 is a partially enlarged view of the molding die according to the present invention as viewed from a side corresponding to a cross section taken along line AA of FIG. 2;

FIG. 7 is a partial perspective view showing an example in which a cylinder head gasket according to a second embodiment of the present invention is applied to a closed deck type multi-cylinder water-cooled engine.

FIG. 8 is a sectional view taken along line CC of FIG. 7;

FIG. 9 is a sectional view taken along the line DD in FIG. 7;

FIG. 10 is a cross-sectional view in which a stopper plate of a conventional cylinder head gasket is connected by a blind stop.

FIG. 11 is a cross-sectional view in which stopper plates of a conventional cylinder head gasket are connected by burring.

FIG. 12 is a partial perspective view showing an example in which a conventional cylinder head gasket is applied to an open deck type multi-cylinder water-cooled engine.

FIG. 13 is a sectional view taken along the line ZZ in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Cylinder head gasket 2 ... Upper board 3 ... Lower board 5 ... Swelling part 5a ... Long side of both sides of a swelling part 5b ... Short side of both sides of a swelling part 4 ... Stopper plate 6 ... Cylinder hole 7 ... Cooling water throttle Hole 8: Oil hole 9: Bolt hole 10a, 10b, 10c: Bore bead 11a, 11b: Peripheral bead 12: Rubber seal material 14: Overhanging part 15: Mold for molding 16: Female mold 16a: Both long sides of female mold 16b: Short sides on both sides of the female mold 17a: One side of the male mold 17b: Other sides of the male mold 17 ... Male mold 21: Cuts on the side of the bulging part 22 ... Outside cuts 23 ... Concave 24 ... Pleated shape 33 ... Cylinder bore 31 ... Cylinder head 32 ... Cylinder block 34 ... Cooling water passage

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Norio Yoshino 93-4 Nakazato, Nihonmatsu-shi, Fukushima F-term in K & K Corporation (reference) 3J040 AA01 AA12 BA01 EA07 EA08 EA10 EA12 EA15 EA17 EA30 EA48 FA01 FA05 HA02 HA05 HA17

Claims (4)

[Claims] 1. A multi-cylinder water-cooled engine includes two or more hard substrates interposed between the mating surfaces of a cylinder head and a cylinder block, and a stopper plate sandwiched between these substrates is softer than the substrates. A rectangular bulge formed by simultaneous crimping for simultaneously connecting all the laminated substrates and the stopper plate is formed in a continuous ring shape having a width extending from around each cylinder bore to the inside of the cooling water passage. In a cylinder head gasket protruding into a cooling water passage around a cylinder bore of the cylinder head or the cylinder block,
An overhang protruding from the outer periphery of the stopper plate is formed at a location of the cylinder head gasket avoiding the cooling water throttle hole, and the lamination is performed with a predetermined molding die at a position straddling the tip of the overhang. The rectangular bulge is formed by pressing simultaneously with all the substrates that are formed, and both long sides of the bulge are punched with cuts and both short sides of the bulge have cuts. A cylinder head gasket characterized in that it is not bent but formed so as to prevent pull-out due to mutual resistance between cuts of each plate material on both long sides of the bulging portion. 2. The method according to claim 1, wherein the predetermined forming mold for forming the bulging portion is:
It has a female mold and a male mold having a rectangular molding surface, the female mold has both long sides and both short sides, and one side of the male mold corresponds to the inner diameter of both short sides of the female mold. A punch is formed by forming a cut in both long sides of the bulge, and the other side of the male mold has an inner diameter narrower than both long sides of the female mold, and both short sides of the bulge are formed. 2. The cylinder head gasket according to claim 1, wherein the gasket is bent. 3. The bulging portion has long sides on both sides formed in a direction along the outer periphery of the cylinder bore, and short sides on both sides of the bulging section formed along a radial direction of the cylinder bore. The cylinder head gasket according to claim 1, wherein the tip of the projecting portion of the stopper plate is accommodated in the middle of both short sides on both sides of the projecting portion. 4. A rubber sealing material is applied to the substrate surface,
By forming a parallel recess along the long side between the short sides on both sides of the molding surface of the female mold of the molding die, and using the female mold for the simultaneous caulking, cuts on both long sides of the bulging portion A fold shape is formed in the vicinity, and the fold shape causes a partial increase in surface pressure near a cut on both long sides of the bulging portion, thereby enhancing resistance to pull-out prevention. Item 2. A cylinder head gasket according to Item 1.