JP3350099B2 - Metal gasket - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a metal cylinder head gasket used for an automobile engine.

[0002]

2. Description of the Related Art In a metal gasket composed of a single thin metal plate or a laminate of a plurality of thin metal plates, a combustion chamber is used to seal a combustion chamber hole, a bolt hole, a water hole, and an oil hole. A seal line is formed by embossing around the hole, around the bolt hole, and around the outer periphery of the gasket. Alternatively, a seal line may be formed by folding instead of embossing, or a seal line may be formed by using embossing and folding together.

[0003]

The metal gasket is bolted with the metal gasket interposed between the cylinder block and the cylinder head. However, since the cylinder block and the cylinder head are not completely rigid, the metal gasket is bolted. The applied force concentrates around the bolt hole of the metal gasket. In other words, from a phenomenal perspective, there is a phenomenon in which the periphery of the female thread portion of the cylinder block is pulled upward by the tightening of the bolt and rises to the gasket side, and the periphery of the bolt hole of the cylinder head is pressed downward. A phenomenon that the gasket side protrudes is observed. For this reason,
A huge surface pressure is applied around the bolt hole of the metal gasket, but the dispersion of the bolt tightening force is reduced by that amount, and the surface pressure at the seal line away from the bolt hole is likely to be insufficient. Become. As a result, a portion of the seal line at the outer peripheral edge of the gasket where the surface pressure is insufficient occurs, and there has been a problem that the seal against the water hole or the oil hole becomes incomplete.

As a method for solving the above-mentioned problem, a method of slightly changing the width of the emboss or slightly increasing the height of the emboss for a seal portion having a low surface pressure is considered. However, adopting such a method has a problem that the number of adjustment steps is increased and it is very difficult, and that the method is not always effective.

An object of the present invention is to solve the above problems.

[0006]

According to the present invention, in order to achieve the above object, a seal line is formed around a combustion chamber hole, around a bolt hole, and around an outer peripheral edge of a gasket by embossing and / or folding. formed, the combustion chamber holes, bolt holes, in the metal gasket interposed between the structure and the cylinder block and cylinder head to seal the water holes and oil hole, the peripheral portion of the bolt hole, bolt The pressure relief portion for preventing the concentration of the force and dispersing the force is characterized in that it is specifically configured as described below .

More specifically, the pressure relief portion is formed by cutting out a part of the metal gasket, making the bolt hole larger than usual, or increasing the thickness of the gasket so that the peripheral portion of the bolt hole has another portion. It is formed so as to be thinner by 0.01 mm or more .

[0008]

[Action] metal gasket of the present invention, the peripheral portion of the bolt hole, so bolt clamping force pressure relief portion to disperse the force by avoiding the concentrated is formed, the metal gasket When the bolt is tightened by being interposed between the cylinder block and the cylinder head, the bolt tightening force is prevented from being concentrated around the bolt hole. It is effectively distributed to the seal line away from the bolt hole, and the surface pressure at that location can be maintained high.

As a result, it is possible to prevent the occurrence of a portion where the surface pressure is insufficient in the seal line on the outer peripheral edge of the gasket, which has been conventionally seen, and to solve the problem that the seal against the water hole or the oil hole becomes incomplete.

[0010]

1 to 4 show a first embodiment in which two thin metal plates (steel plates) 1a and 1b are laminated, and a combustion chamber hole 2 is formed.
The seal lines L ₁ , L ₂ ,
L ₃ to form a combustion chamber hole 2, the bolt holes 3, to a metal gasket configured to seal the water hole 5 and the oil hole portion 6.

[0011] The upper metal sheet 1a is formed flat, the lower thin metal plate 1b has the seal line L _1, L _2, L ₃ formed by embossing. Two bolt holes left, each of the right side portion s to with this metal gasket (indicated by B ₁₎ bolt holes at four corners with a 3 (B
₍ Indicated by ₂ ). Although the periphery of the bolt hole 3 shown by B ₁ normal seal line L ₁ is formed,
Around each bolt hole 3 shown in B _2, the pressure relief portion 8a to disperse the force by avoiding the tightening force of the bolt 7 is concentrated is formed.

As shown in FIGS. 1 and 2, the pressure relief portion 8a is formed by cutting out the periphery of the bolt hole 3 (B ₂ ) of the upper thin metal plate 1a. FIG. 1
(A), the seal line L ₂ formed around the bolt hole 3 (B _2), are formed continuously from the seal line L ₃ formed on the gasket peripheral edge.

The metal gasket having the above structure is interposed between the cylinder block 9 and the cylinder head 10 as shown in FIG. 2 (FIG. 2 shows a state before bolt tightening).
It is tightened by bolts 7.

FIG. 5 shows a second embodiment. In the second embodiment, the upper and lower metal sheets 1a and 1b are
The pressure relief portion 8b is formed by notching the periphery of (B ₂ ).

FIG. 6 shows a third embodiment. In the third embodiment, a pressure relief portion 8c is formed by using a thin portion around the bolt hole 3 (B ₂ ) of the upper thin metal plate 1a. The thin portion is made thinner by 0.01 mm or more than other portions.

FIG. 7 shows a fourth embodiment. In this fourth embodiment, the pressure relief portion 8d is formed by forming the hole diameter of the bolt hole portion 3 (B ₂ ) of the upper metal thin plate 1a to be a stupid hole larger than usual.

FIG. 8 shows a fifth embodiment. In the fifth embodiment, a pressure relief portion 8e is formed by forming the upper and lower metal thin plates 1a and 1b into holes whose bolt diameters of the bolt holes 3 (B ₂ ) are larger than usual. It is.

Although the above embodiment relates to a metal gasket formed by laminating two metal sheets 1a and 1b, based on a similar idea, the present invention relates to a metal gasket constituted by a single metal sheet. It can also be applied to a metal gasket formed by laminating three or more thin metal plates. The above embodiment the peripheral portion of the 4 bolt holes 3 disposed in the corner portion (B ₁₎ a bolt hole 3 except for (B _2), but forms a pressure relief portion 8 a to 8 e, 4 also peripheral portion of the bolt hole 3 disposed in a corner portion (B _1), it is possible to form a similar pressure relief portion 8a~8e above.

[0019]

According to the present invention, it is possible to uniformly distribute the bolt tightening force to the entire seal line, and to provide a metal gasket having a high sealing property. Further, since the bolt tightening force can be effectively used as the seal surface pressure, the bolt tightening force can be reduced as compared with the conventional example. Furthermore, since the bulge-like deformation generated in the bolt tightening portion of the cylinder block and the cylinder head at the time of bolt tightening can be absorbed by the pressure relief portion, the rigidity of the engine can be reduced.

[Brief description of the drawings]

FIG. 1 shows a main part of a first embodiment, (a) is a plan view,
(B) is a longitudinal side view.

FIG. 2 is a longitudinal sectional side view showing a state of being assembled to the engine of the first embodiment.

FIG. 3 is a bottom view showing the entire first embodiment.

FIG. 4 is a sectional view taken along the line AA of FIG. 3;

5A and 5B show a main part of a second embodiment, in which FIG.
(B) is a longitudinal side view.

6A and 6B show a main part of a third embodiment, in which FIG.
(B) is a longitudinal side view.

FIGS. 7A and 7B show a main part of a fourth embodiment, where FIG.
(B) is a longitudinal side view.

FIG. 8 shows a main part of a fifth embodiment, where (a) is a plan view,
(B) is a longitudinal side view.

[Explanation of symbols]

1a, 1b metal sheet 2 a combustion chamber hole 3 bolt holes 4 gasket peripheral edge 5 water hole portion 6 lubrication hole portion 7 volts 8a~8e pressure relief portion 9 cylinder block 10 cylinder head L _1, L _2, L ₃ seal line

──────────────────────────────────────────────────続 き Continued on the front page (56) References JP-A-3-46070 (JP, U) JP-A-3-119554 (JP, U) (58) Fields surveyed (Int. Cl. ⁷ , DB name) F16J 15/08

Claims (6)

(57) [Claims] 1. A seal line is formed around an opening of a combustion chamber, around an opening of a bolt, and around an outer peripheral edge of a gasket by embossing or / and turning over, and a combustion chamber hole, a bolt hole, a water hole and an oil are formed. in the metal gasket interposed between the structure and the cylinder block and the cylinder head to seal the hole, the peripheral portion of the bolt hole, to disperse the force by avoiding the bolt clamping force is concentrated Form a pressure relief part and cut a part of the metal gasket.
A metal gasket, wherein the pressure relief portion is formed in a chipped manner. 2. The periphery of a combustion chamber hole, the periphery of a bolt hole, and the like.
Embossed or / and / or
A seal line is formed by turning back,
A series of holes configured to seal the
Meta between the cylinder block and cylinder head
Bolts around the bolt holes
To prevent the tightening force from concentrating and disperse it
Form a pressure relief part and stack multiple metal sheets
Tal gasket is composed of several metal sheets
In the case of a thin plate only, the pressure relief part
Metal gasket characterized by comprising: 3. The periphery of a combustion chamber hole, the periphery of a bolt hole and the like.
Embossed or / and / or
A seal line is formed by turning back,
A series of holes configured to seal the
Meta between the cylinder block and cylinder head
Bolts around the bolt holes
To prevent the tightening force from concentrating and disperse it
Form a pressure relief part and bolt holes as compared to normal
Characterized in that the pressure relief portion is configured to be formed large.
Metal gasket. 4. The periphery of a combustion chamber hole, the periphery of a bolt hole, and the like.
Embossed or / and / or
A seal line is formed by turning back,
A series of holes configured to seal the
Meta between the cylinder block and cylinder head
Bolts around the bolt holes
To prevent the tightening force from concentrating and disperse it
Form a pressure relief part and stack multiple metal sheets
Tal gasket is composed of several metal sheets
Bolt hole is larger than usual for thin plate only
A metal gasket formed to form the pressure relief portion . 5. The periphery of a combustion chamber hole, the periphery of a bolt hole and the like.
Embossed or / and / or
A seal line is formed by turning back,
A series of holes configured to seal the
Meta between the cylinder block and cylinder head
Bolts around the bolt holes
To prevent the tightening force from concentrating and disperse it
Form a pressure relief part and reduce the thickness of the gasket
The periphery of the hole becomes thinner by 0.01 mm or more than other parts
A metal gasket characterized by having a pressure relief portion formed as described above . 6. The periphery of a combustion chamber hole, the periphery of a bolt hole, and the like.
Embossed or / and / or
A seal line is formed by turning back,
A series of holes configured to seal the
Meta between the cylinder block and cylinder head
Bolts around the bolt holes
To prevent the tightening force from concentrating and disperse it
Form a pressure relief part and stack multiple metal sheets
Tal gasket is composed of several metal sheets
For thin plates only, adjust the thickness of the metal
So that the surrounding area is at least 0.01 mm thinner than other parts
A metal gasket characterized by forming a pressure relief portion by forming a pressure relief portion .