JP2006144654A - Gasket for cylinder head cover - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a gasket for a cylinder head cover for improving productivity. <P>SOLUTION: This gasket 3 for the elastic material cylinder head cover, which is interposed in the joints 1a, 1b, 2a, 2b between a cylinder head 1 and the cylinder head cover 2, comprises a peripheral seal part 3a arranged between the joints 1a, 2a between the peripheral wall of the cylinder head 1 and the peripheral wall of the cylinder head cover 2, and a plug seal part 3a arranged between the mutual joints 1b, 2b between the cylinder head 1 forming the storage part 11 of an ignition plug 5 and the plug storage wall of the cylinder head cover 2. The peripheral seal part 3a and plug seal part 3b are formed separately, provided with connecting pieces 31a, 31b, and interposed in the joints 1a, 1b, 2a, 2b between the cylinder head 1 and the cylinder head cover 2 with the connecting pieces 31a, 31b connected to each other. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a gasket, and more particularly to a gasket for a cylinder head cover that is interposed at a joint between a cylinder head and a cylinder head cover.

Conventionally, a cylinder head cover is attached to the upper part of a cylinder head that constitutes a part of a combustion chamber of an engine mounted on a vehicle or the like, and rubber is used at these joints to ensure a sealing property between the two. A gasket made of an elastic material such as is interposed.
The gasket (cylinder head cover gasket) interposed in the joint portion includes a gasket disposed between the joint portion between the outer peripheral wall of the cylinder head and the outer peripheral wall of the cylinder head cover, and an ignition provided in accordance with the number of cylinders. What is constituted by integrally molding two gaskets: a spark plug housing wall on the cylinder head side that forms the plug housing portion, and a gasket disposed between the joint portions of the ignition plug housing wall on the cylinder head cover side. is there.

The following Patent Document 1 discloses such a gasket, wherein the two gaskets are connected by a “bridge connecting portion” parallel to the cam shaft direction and are integrally formed. Has been proposed.
Japanese Utility Model Publication No. 1-1634

  However, in the case shown above, since the two gaskets are integrally molded, it is necessary to secure a large space corresponding to at least the area of the contour portion in the die, and the number of pieces in one die is limited. There is a problem that it is inevitably reduced and productivity is poor. In addition, when the gasket arranged between the joints on the outer peripheral wall of the cylinder head and the cylinder head cover, for example, is damaged during manufacturing, even if there is no problem with the other gasket There is also a problem that the gasket as a whole becomes a defective product.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a cylinder head cover gasket that is improved in productivity.

  In order to solve the above-mentioned problem, the cylinder head cover gasket according to the invention of claim 1 is made of an elastic material, and is interposed at a joint portion between the cylinder head and the cylinder head cover. An outer peripheral seal portion disposed between the joint portions of the wall and the outer peripheral wall of the cylinder head cover, and a plug seal disposed between the joint portions of the cylinder head forming the spark plug housing portion and the plug housing wall of the cylinder head cover. The outer peripheral seal portion and the plug seal portion are formed separately from each other, and each has a connecting piece, and the connecting portion between the cylinder head and the cylinder head cover in a state where the connecting pieces are connected to each other. It is characterized in that it is intervened in.

Specifically, the outer peripheral seal portion and the plug seal portion are coupled and integrated with each other by the method proposed in the following claims.
According to a second aspect of the present invention, in the first aspect, at least one engagement hole is formed in one of the connection pieces, and the two connection pieces are connected to each other by inserting and engaging the other connection piece into the engagement hole. It was made to let it be made to do.
A third aspect of the present invention is characterized in that, in the second aspect of the present invention, the front end of the other connecting piece is formed with a retaining claw portion for holding the state inserted and engaged with the engagement hole. To do.
According to a fourth aspect of the present invention, in the second or third aspect, two engagement holes are formed along the longitudinal direction of one of the connection pieces, and the other connection piece is sequentially inserted into the two engagement holes. Thereby, both connecting pieces are connected to each other.

According to the cylinder head cover gasket according to the first aspect of the present invention, since the outer peripheral seal portion and the plug seal portion are formed separately from each other, it is possible to mold in a flat shape for the outer peripheral seal portion. Therefore, the die-taking area required for this is reduced, and a large number of molds can be obtained in one mold when manufacturing. In this case, a flat outer peripheral seal portion is obtained. However, since the gasket is made of an elastic material such as rubber, the joint portion can be deformed so as to follow the shape thereof. Further, even if there is a defective product in either the outer peripheral seal portion or the plug seal portion, it is only necessary to replace it, and the defective product can be reduced, so that productivity can be improved.
Further, both the outer peripheral seal portion and the plug seal portion are provided with connecting pieces, and the connecting pieces are connected to each other so as to be interposed at the joint between the cylinder head and the cylinder head cover, so that the number of gasket parts increases. In other words, both joints can be sealed with a single gasket, and attachment and removal operations can be performed easily.

  According to the cylinder head cover gaskets according to claims 2 to 4, both can be connected by a simple method, and thus the productivity is good.

The best mode for carrying out the present invention will be described below with reference to the drawings. 1 is a cross-sectional view showing the periphery of a cylinder head part where a cylinder head cover gasket according to the present invention is interposed, FIG. 2A is an enlarged view of a portion X in FIG. 1, and FIG. 2B is a portion Y in FIG. FIG. 3 is a perspective view of the gasket, FIGS. 4 and 5 are views showing a connecting method of the gasket, and FIG. 6 is a partially cutaway plan view showing an example of a molding die of the gasket.
The configuration of the cylinder head or the like is not limited to that shown in the figure.

  FIG. 1 shows an example of a structure around a cylinder head and a cylinder head cover portion of an engine mounted on an automobile. A cylinder head cover 2 is attached to an upper portion of the cylinder head 1 so as to cover a cam shaft 4 and the like. Gaskets 3 made of an elastic material such as rubber are interposed at joints 1a, 1b, 2a and 2b between the head 1 and the cylinder head cover 2 in order to ensure a sealing property between them.

The cylinder head 1 is provided with an intake port 6 that serves as an intake passage for an air-fuel mixture and an exhaust port 7 that serves as an exhaust passage for combustion gas in communication with a combustion chamber (not shown) of the engine. By opening and closing the exhaust valve 9, the air-fuel mixture is introduced into the combustion chamber and sealed, and the combustion gas is discharged. The intake valve 8 and the exhaust valve 9 are opened and closed by the swing of the valve rod 10 against the elasticity of the compression springs 8a and 9a by the action of the cam 4a that rotates as the cam shaft 4 rotates.
The cylinder head 1 is controlled by a control unit (not shown), and includes an ignition plug 5 that causes electric sparks to fly and ignites an air-fuel mixture in the combustion chamber to cause combustion, and the ignition plug 5 is accommodated in the ignition plug. The tip electrode portion (not shown) faces the combustion chamber.

2A is an enlarged view of the X portion in FIG. 1, and FIG. 2B is an enlarged view of the Y portion in FIG.
The cylinder head cover gasket 3 of the present embodiment includes an outer peripheral seal portion 3 a disposed between the joint portions 1 a and 2 a between the outer peripheral wall of the cylinder head 1 and the outer peripheral wall of the cylinder head cover 2, and an accommodating portion 11 of the spark plug 5. The cylinder head 1 and the cylinder head cover 2 to be formed include a plug seal portion 3b disposed between the joint portions 1b and 2b of the plug housing wall.
As shown in FIGS. 2A and 2B, a gasket groove 13 a is provided along the circumferential direction in the joint portion 2 a of the outer peripheral wall of the cylinder head cover 2, and the joint portion 2 b of the plug housing wall of the cylinder head cover 2 is provided in the joint portion 2 b. Also, a gasket groove 13b is provided along the circumferential direction. With the outer peripheral seal portion 3a and the plug seal portion 3b fitted in the gasket grooves 13a and 13b, the cylinder head cover 2 is assembled to the cylinder head 1, and bolts are inserted into the bolt holes 12b provided in the joint portion 2a of the cylinder head cover 2. The cylinder head 1 and the cylinder head cover 2 are fastened integrally by inserting the screw 12 and screwing it into a nut portion 12a provided in the joint portion 1a of the cylinder head 1.
Here, the gasket 3 is not particularly limited, but a rubber material having an excellent elastic deformation amount is desirable. For example, natural rubber, nitrile rubber, ethylene propylene rubber, acrylic rubber, silicone rubber, fluorine rubber, or the like can be used. .

FIG. 3 is a perspective view showing a cylinder head cover gasket according to the present invention, and FIGS. 4 and 5 are plan views and cross-sectional views showing various examples of connecting methods of the cylinder head cover gasket.
The cylinder head cover gasket 3 to be described later has a shape corresponding to the configuration, shape or position of the outer peripheral wall of the cylinder head 1, the accommodating portion 11 of the spark plug 5, the bolt hole, etc. It is not limited to the shape. Further, the gasket 3 shown in FIG. 3 is shown upside down in the case where it is actually attached, and the connecting piece 31a of the outer peripheral seal portion 3a and the connecting piece 31b of the plug seal portion 3b shown in FIGS. 3 to 5 are connected. The connected seam does not matter up and down. That is, the engagement hole 14 may be formed in either one of the connection pieces 31a and 31b, and is not limited to the example shown in the drawing.

  In the cylinder head cover gasket 3 of the present embodiment, the outer peripheral seal portion 3a and the plug seal portion 3b are formed separately, and are provided with connecting pieces 31a and 31b on both sides, and the connecting pieces 31a and 31b are connected to each other. In this state, the cylinder head 1 and the cylinder head cover 2 are interposed in joints 1a, 1b, 2a, and 2b.

Here, various methods for connecting the outer peripheral seal portion 3a and the plug seal portion 3b are conceivable, but any method can be used as long as it is a simple method and firmly connected to each other without using a separate member for connection.
For example, at least one engaging hole 14 is formed in one of the connecting pieces 31a and 31b, and the other connecting piece is inserted into and engaged with the engaging hole 14, thereby connecting the connecting pieces 31a and 31b to each other. There is a way to connect.
In FIG. 3, two engagement holes 14 are formed along the longitudinal direction of the connection piece 31 a of the outer peripheral seal portion 3 a, and the connection pieces 31 b of the plug seal portion 3 b are sequentially inserted into the two engagement holes 14. In this example, one gasket 3 is connected.

4 (a) and 4 (b) show an example of connection by the same method as in FIG. 3, (a) is a plan view, and (b) is a cross-sectional view.
FIG. 4C shows another example of connection, in which one engagement hole 14 is formed in the connection piece 31a of the outer peripheral seal portion 3a, and on the front side of the connection piece 31b of the plug seal portion 3b. , A retaining claw portion 31c for holding the state inserted and engaged with the engagement hole 14 is formed and connected.

FIGS. 5 (a) and 5 (b) show yet another connection example, in which one circular engagement hole 14 is formed in the connection piece 31a of the outer peripheral seal portion 3a like a button hole, and the plug seal portion 3b. On the front side of the connecting piece 31b, a hook-shaped retaining claw portion 31c for holding the state fitted in the engaging hole 14 is formed and connected. Of course, the number of the engagement holes 14 is not limited to one, and a plurality of engagement holes 14 may be provided.
In addition, any one of the connecting pieces 31a and 31b may be formed in a hollow tube shape, and the other may be formed in a column shape having a retaining claw portion such as a bamboo shoot, and both may be butt-fitted and connected. .
According to the above-described configuration, even if the outer peripheral seal portion 3a and the plug seal portion 3b are separately formed, since they are one member when interposed as the gasket 3, the number of parts does not increase. , Mounting and removal work can be performed easily.

FIG. 6 is a partially cutaway plan view showing an example of a molding die for a cylinder head cover gasket according to the present invention. FIG. 6 (a) is a die of the outer peripheral seal portion 3a, and FIG. 6 (b) is a plug seal portion 3b. Each mold is shown. In addition, the structure of a metal mold | die is not restricted to this.
The raw material of the gasket 3 is put into a mold cavity as shown here, and is heated and cured by pressurization, and a cylinder head cover gasket as shown in FIG. 3 is molded.
Conventionally, since the outer peripheral seal portion 3a and the plug seal portion 3b are integrally molded, the outer peripheral seal portion 3a has to be molded in an assembled state. However, according to the above configuration, the outer peripheral seal portion 3a is illustrated in FIG. Since it can be deformed into a flat shape as shown in FIG. 6 (a), the number of pieces taken from one mold can be increased, and productivity can be improved. That is, since the gasket of the present embodiment is made of an elastic material, it can be fitted into the gasket groove 13 of the cylinder head cover 2 in the state shown in FIG.

  Further, in the case of the gasket 3 that is molded integrally, if the burr is formed on either the outer peripheral seal portion 3a or the plug seal portion 3b or if there is a scratch, the entire gasket 3 will be treated as a defective product. According to the configuration, even if either one is a defective product, the entire gasket 3 is not defective. Therefore, the number of defective products as a whole can be reduced.

It is sectional drawing which shows the cylinder head site | part periphery where the gasket for cylinder head covers of this invention is interposed. It is an enlarged view of the X section in FIG. It is a perspective view which shows the gasket for cylinder head covers of this invention. (A) (b) (c) It is the top view and sectional drawing which showed various examples of the connection method of the gasket for cylinder head covers. (A) (b) It is the top view and sectional drawing which showed an example of the connection method of the gasket for cylinder head covers. (A) (b) It is a partial notch top view which shows an example of the shaping die of the cylinder head cover gasket of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Cylinder head 1a, 1b Joint part 2 Cylinder head cover 2a, 2b Joint part 3 (For cylinder head covers) Gasket 3a Outer periphery seal part 3b Plug seal part 31a, 31b Connecting piece 5 Spark plug

Claims (4)

A gasket for a cylinder head cover made of an elastic material interposed at a joint between the cylinder head and the cylinder head cover,
Between the outer peripheral seal portion disposed between the joint between the outer peripheral wall of the cylinder head and the outer peripheral wall of the cylinder head cover, and the joint between the cylinder head forming the spark plug housing portion and the plug housing wall of the cylinder head cover. It consists of a plug seal part arranged,
The outer peripheral seal portion and the plug seal portion are formed separately from each other, and are provided with connecting pieces on both sides, and are interposed in a joint portion between the cylinder head and the cylinder head cover in a state where the connecting pieces are connected to each other. A gasket for a cylinder head cover, characterized by being made as described above. In claim 1,
At least one engaging hole is formed in one of the connecting pieces, and the connecting piece is connected to each other by inserting and engaging the other connecting piece into the engaging hole. Head cover gasket. In claim 2,
A cylinder head cover gasket, characterized in that a retaining claw portion is formed on the front side of the other connecting piece to hold the inserted and engaged state in the engaging hole. In claim 2 or 3,
Two engaging holes are formed along the longitudinal direction of one connecting piece, and the other connecting piece is inserted sequentially into the two engaging holes so that the connecting pieces are connected to each other. A gasket for a cylinder head cover.

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