JP4712165B2

JP4712165B2 - Metal gasket

Info

Publication number: JP4712165B2
Application number: JP2000217283A
Authority: JP
Inventors: 耕作植田; 順岡野
Original assignee: Japan Metal Gasket Co Ltd
Current assignee: Japan Metal Gasket Co Ltd
Priority date: 2000-07-18
Filing date: 2000-07-18
Publication date: 2011-06-29
Anticipated expiration: 2020-07-18
Also published as: JP2002031237A

Description

【０００１】
【発明の属する技術分野】
本発明は、燃焼室孔の周囲にビードが設けられた基板と、該基板より薄肉に形成されて前記基板に積層されたシム板とを備え、シリンダブロックとシリンダヘッドとの接合面間に介装して締結ボルトで締め付けることにより、前記接合面間をシールするようにした金属ガスケットに関する。
【０００２】
【従来の技術】
従来のこの種の金属ガスケットとしては、例えば、特開平６−１１７５４２号公報や特開平１０−２８１２２８号公報に示すように、基板の燃焼室孔の周縁部（基板ビードより燃焼室孔側）に該基板より薄肉のシム板を積層して該燃焼室孔の周縁部と他の部分との間に板厚差を設け、かかる板厚差により、シリンダヘッドとシリンダブロックとの接合面間に介装して締結ボルトで締め付ける際に、燃焼室孔の周縁部に最も面圧が集中するようにし、これにより、シリンダボア端部周縁に最大荷重をかけてシールするようにしたものが知られている。
【０００３】
【発明が解決しようとする課題】
しかしながら、上記従来の金属ガスケットにおいては、締結ボルト近傍に比べて締結ボルト間の方が面圧が低くなるため、特に、運転時に高温／高圧ガスを発生して大きな振動振幅を発生する最近のエンジンに使用する場合には、締結ボルト間の低面圧域の振動振幅の増大により基板の燃焼室孔の周囲に設けられたビードだけでは十分なシール性能が得られないという不都合がある。
【０００４】
本発明はかかる不都合を解消するためになされたものであり、燃焼室孔の全周にわたって十分なシール性能を得ることができる金属ガスケットを提供することを目的とする。
【０００５】
【課題を解決するための手段】
かかる目的を達成するために、請求項１に係る金属ガスケットは、燃焼室孔の周囲にビードが設けられた基板と、該基板に積層されたシム板とを備え、シリンダブロックとシリンダヘッドとの接合面間に介装して締結ボルトで締め付けることにより、前記接合面間をシールするようにした金属ガスケットにおいて、
前記シム板は前記基板より薄肉に形成され、前記シム板を前記燃焼室孔の周囲に前記基板のビードを覆うように配置すると共に、そのシム板の燃焼室孔から離間する側の端部を、基板の外周縁及びボルト孔よりも内側に位置し、
且つ、該シム板の燃焼室孔側の端部の厚さ方向の枚数を複数にして燃焼室孔側の端部周縁である周縁部の肉厚が最も厚くなるようにすると共に、前記シム板の前記基板のビードの前記燃焼室孔から離間する側であって前記基板のビードと基板厚さ方向で重ならない位置に補助ビードを設け、その補助ビードを、前記基板の燃焼室孔を無端状に囲繞するように設けると共に、前記基板に設けたビードよりも低く設定することで、
シリンダブロックとシリンダヘッドとの接合面間に介装して締結ボルトで締め付けると、基板のビード、補助ビード、周縁部の順に圧縮変形することを特徴とする。
【０００６】
請求項２に係る金属ガスケットは、請求項１において、前記シム板の燃焼室孔側の端部を折り返して該端部の厚さ方向の枚数を２枚にしたことを特徴とする。
請求項３に係る金属ガスケットは、請求項１又は２において、前記シム板の燃焼室孔側の端部の厚さを該燃焼室孔の周方向に沿って変化させたことを特徴とする。
【０００７】
請求項４に係る金属ガスケットは、請求項１〜３のいずれか一項において、前記シム板の燃焼室孔側の端部の幅を該燃焼室孔の周方向に沿って変化させたことを特徴とする。
【０００８】
【発明の実施の形態】
以下、本発明の実施の形態を図を参照して説明する。
図１は本発明の実施の形態の一例である金属ガスケットを説明するための要部平面図、図２は図１のＩ−Ｉ線断面図、図３はシム板の拡大断面図、図４〜図８は本発明の他の実施の形態を説明するための説明図である。
【０００９】
図１〜図３を参照して、この金属ガスケットは、燃焼室孔２の周囲にフルビード３が形成された基板１と、基板１より薄肉に形成されて該基板１に積層されたシム板４とを備えている。なお、図１において符号６はボルト孔、７は水孔、８はオイル孔であり、いずれも基板１のフルビード３の外側に配置されている。
シム板４は、基板１の燃焼室孔２の周囲にフルビード３の凸部側を覆うように配置されており、燃焼室孔２側の端部が上方に折り返されて厚さ方向に二枚積層され、これにより、燃焼室孔２側の端部周縁（以下、周縁部４ａという）の肉厚が最も厚くなるようにしている。
【００１０】
また、シム板４の周縁部４ａは、ボルト締結時の締め付け力が大きい締結ボルトのボルト孔６近傍の厚さが、締め付け力が小さい各ボルト孔６間の厚さより薄くなっており、この実施の形態では、鍛圧成形により、周縁部４ａの厚さがボルト孔６近傍から各ボルト孔６間に向けて次第に厚くなるようにして燃焼室孔２の周方向に沿って抑揚を付けている。なお、図１では、シム板４は基板１の裏面に配置され、また、シム板４の燃焼室孔２から離間する側の端部は基板１の外周縁より内側に位置している。
【００１１】
ここで、この実施の形態では、基板１のフルビード３の燃焼室孔２から離間する側に補助ビード５を設けている。補助ビード５はフルビードとされて基板１のフルビード３より低く且つ厚さ方向に弾性変形可能とされており、凸部側が基板１を向くように配置されている。
そして、かかる構成の金属ガスケットをシリンダブロックとシリンダヘッドとの間に介装して締結ボルトで締め付けると、フルビード３、補助ビード５、周縁部４ａの順に板厚方向に圧縮変形し、該締め付けは板厚が変化しない基板１の外周縁部の板厚まで行われる。締め付け終了時においては、最も板厚の厚い周縁部４ａに面圧が集中してシール条件が一番厳しいシリンダボア端部周縁に最大荷重が作用し、これにより、エンジンの振動振幅を抑えると共にシリンダボア端部周縁に対する高面圧の一次シールがなされ、且つ、フルビード３及び補助ビード５の全屈が防止され、更には、圧縮変形したフルビード３の弾性反発力よるシール圧、及び補助ビード５の弾性反発力によるシール圧によって高温高圧の燃焼ガスに対してフルビード３による二次シール及び補助ビード５による三次シールがなされると共に、補助ビード５によるシール圧で水孔７からの冷却水のフルビード３側への浸入が阻止される。
【００１２】
また、上述したように、シム板４の周縁部４ａは、ボルト締結時の締め付け力が大きい締結ボルトのボルト孔６近傍の厚さが、締め付け力が小さい各ボルト孔６間の厚さより薄くされて燃焼室孔２の周方向に沿って板厚に抑揚が付けられているため、シリンダボア端部周縁における周方向のシール圧の均一化を図ることができる。
【００１３】
なお、上記実施の形態では、補助ビード５をフルビードとした場合を例に採ったが、これに代えて、補助ビード５を例えばステップビードとしてもよい。
また、上記実施の形態では、シム板４の燃焼室孔２側の端部を折り返して、該周縁部４ａの厚さ方向の枚数を２枚にした場合を例に採ったが、必ずしも折り返しによる必要はなく、例えば、シム板４の燃焼室孔２側の端部に環状のシム板を積層して溶接等により接合するようにしてもよい。
【００１４】
次に、図４〜図８を参照して、本発明の他の実施の形態である金属ガスケットを説明する。
図４及び図５は、シム板４の周縁部４ａの厚さを、上記実施の形態と同様に、ボルト締結時の締め付け力が大きい締結ボルトのボルト孔６近傍は薄くし、締め付け力が小さい各ボルト孔６間は厚くすると共に、シム板４の周縁部４ａの折り返し幅を、ボルト締結時の締め付け力が大きい締結ボルトのボルト孔６近傍は狭くし、締め付け力が小さい各ボルト孔６間は広くしたものであり、この実施の形態では、周縁部４ａの折り返し幅がボルト孔６近傍から各ボルト孔６間に向けて次第に広くなるようにして燃焼室孔２の周方向に沿って板幅に抑揚を付けている。これにより、シリンダボア端部周縁における周方向及び径方向のシール圧の均一化を図るようにしている。また、シム板４の周縁部４ａの折り返し幅を締結ボルトのボルト孔６近傍は狭くし、締め付け力が小さい各ボルト孔６間は広くすることにより、ボルト孔６近傍の板厚をプレス成形によって薄くする際に板厚方向に変形し易くすることができる。
【００１５】
図６は上下の二枚の基板１間にシム板４を配置した例であり、上下の基板１のフルビード３は凸部側が互いに対向配置されている。図７は上下の二枚の基板１間にシム板４を配置した例であるが、上下の基板１のフルビード３の凹部側が互いに対向配置されている。図８は上下の二枚の基板１間にシム板４及び厚さ調整用の副板１０を配置した例であり、上下の基板１のフルビード３は凸部側が互いに対向配置され、副板１０のシム板４の周縁部４ａの幅に対応する範囲に該シム板４の板厚に応じて板厚の略１／３〜１／２の段差を設けて、副板１０の段差凹部１１に周縁部４ａを嵌合した例である。
【００１６】
【発明の効果】
上記の説明から明らかなように、請求項１又は２の発明によれば、燃焼室孔の全周にわたって十分なシール性能を得ることができるという効果が得られる。
請求項３の発明では、請求項１又は２の発明に加えて、シリンダボア端部周縁における周方向のシール圧の均一化を図ることができるという効果が得られる。
【００１７】
請求項４の発明では、請求項１〜３のいずれか一項の発明に加えて、シリンダボア端部周縁における径方向のシール圧の均一化を図ることができるという効果が得られる。
【図面の簡単な説明】
【図１】本発明の実施の形態の一例である金属ガスケットを説明するための要部平面図である。
【図２】図１のＩ−Ｉ線断面図である。
【図３】シム板の拡大断面図である。
【図４】本発明の他の実施の形態である金属ガスケットを説明するための要部平面図である。
【図５】シム板の拡大断面図である。
【図６】本発明の他の実施の形態である金属ガスケットを説明するための説明的断面図である。
【図７】本発明の他の実施の形態である金属ガスケットを説明するための説明的断面図である。
【図８】本発明の他の実施の形態である金属ガスケットを説明するための説明的断面図である。
【符号の説明】
１…基板
２…燃焼室孔
３…フルビード（基板ビード）
４…シム板
４ａ…周縁部
５…補助ビード
６…ボルト孔
７…水孔[0001]
BACKGROUND OF THE INVENTION
The present invention includes a substrate having a bead around the combustion chamber hole and a shim plate formed thinner than the substrate and stacked on the substrate, and is interposed between the joint surfaces of the cylinder block and the cylinder head. It is related with the metal gasket which sealed between the said joint surfaces by mounting | wearing and fastening with a fastening bolt.
[0002]
[Prior art]
As a conventional metal gasket of this type, for example, as shown in JP-A-6-117542 and JP-A-10-281228, the peripheral portion of the combustion chamber hole of the substrate (on the combustion chamber hole side from the substrate bead). A shim plate that is thinner than the substrate is laminated to provide a difference in the plate thickness between the peripheral edge of the combustion chamber hole and the other part, and the plate thickness difference causes a gap between the joint surface of the cylinder head and the cylinder block. It is known that when mounting and tightening with a fastening bolt, the surface pressure is most concentrated on the peripheral edge of the combustion chamber hole, and the cylinder bore end peripheral edge is sealed by applying a maximum load. .
[0003]
[Problems to be solved by the invention]
However, in the conventional metal gasket, since the surface pressure is lower between the fastening bolts than in the vicinity of the fastening bolts, a recent engine that generates a high vibration amplitude by generating high temperature / high pressure gas during operation. In the case of using for this, there is an inconvenience that sufficient sealing performance cannot be obtained with only the beads provided around the combustion chamber hole of the substrate due to the increase of the vibration amplitude in the low surface pressure region between the fastening bolts.
[0004]
The present invention has been made in order to eliminate such inconvenience, and an object of the present invention is to provide a metal gasket capable of obtaining sufficient sealing performance over the entire circumference of the combustion chamber hole.
[0005]
[Means for Solving the Problems]
In order to achieve such an object, a metal gasket according to claim 1 is provided with a substrate provided with beads around the combustion chamber hole, and a shim plate laminated on the substrate, and includes a cylinder block and a cylinder head. In the metal gasket that is configured to seal between the joint surfaces by interposing between the joint surfaces and tightening with a fastening bolt,
The shim plate is formed thinner than the substrate, and the shim plate is arranged around the combustion chamber hole so as to cover the bead of the substrate, and an end portion of the shim plate on the side away from the combustion chamber hole is disposed. , Located inside the outer peripheral edge of the substrate and the bolt hole,
In addition, the shim plate is configured such that the thickness of the peripheral edge, which is the peripheral edge of the combustion chamber hole side, is maximized by increasing the number of sheets in the thickness direction at the end of the shim plate on the combustion chamber hole side. An auxiliary bead is provided on a side of the substrate bead that is away from the combustion chamber hole and does not overlap with the substrate bead in the substrate thickness direction, and the auxiliary bead has an endless shape in the combustion chamber hole of the substrate. And so as to be surrounded by, and set lower than the beads provided on the substrate,
When it is interposed between the joint surfaces of the cylinder block and the cylinder head and tightened with a fastening bolt, it is compressed and deformed in the order of the bead of the substrate, the auxiliary bead, and the peripheral portion.
[0006]
A metal gasket according to a second aspect is the metal gasket according to the first aspect, wherein the end portion of the shim plate on the combustion chamber hole side is folded back so that the number of the end portions in the thickness direction is two.
A metal gasket according to a third aspect is characterized in that, in the first or second aspect, the thickness of the end portion of the shim plate on the combustion chamber hole side is changed along the circumferential direction of the combustion chamber hole.
[0007]
A metal gasket according to a fourth aspect is the metal gasket according to any one of the first to third aspects, wherein the width of the end portion of the shim plate on the combustion chamber hole side is changed along the circumferential direction of the combustion chamber hole. Features.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
1 is a plan view of an essential part for explaining a metal gasket as an example of an embodiment of the present invention, FIG. 2 is a cross-sectional view taken along the line II of FIG. 1, FIG. 3 is an enlarged cross-sectional view of a shim plate, and FIG. FIG. 8 is an explanatory diagram for explaining another embodiment of the present invention.
[0009]
1 to 3, this metal gasket includes a substrate 1 in which a full bead 3 is formed around a combustion chamber hole 2, and a shim plate 4 that is formed thinner than the substrate 1 and is laminated on the substrate 1. And. In FIG. 1, reference numeral 6 is a bolt hole, 7 is a water hole, and 8 is an oil hole, both of which are arranged outside the full bead 3 of the substrate 1.
The shim plate 4 is arranged around the combustion chamber hole 2 of the substrate 1 so as to cover the convex portion side of the full bead 3, and the end portion on the combustion chamber hole 2 side is folded upward to be two in the thickness direction. Thus, the thickness of the peripheral edge (hereinafter referred to as the peripheral edge 4a) on the combustion chamber hole 2 side is maximized.
[0010]
Further, in the peripheral portion 4a of the shim plate 4, the thickness in the vicinity of the bolt hole 6 of the fastening bolt having a large fastening force at the time of bolt fastening is thinner than the thickness between the bolt holes 6 having a small fastening force. In this embodiment, the forging is performed along the circumferential direction of the combustion chamber hole 2 such that the thickness of the peripheral edge portion 4a gradually increases from the vicinity of the bolt holes 6 to between the bolt holes 6 by forging. In FIG. 1, the shim plate 4 is disposed on the back surface of the substrate 1, and the end of the shim plate 4 on the side away from the combustion chamber hole 2 is located inside the outer peripheral edge of the substrate 1.
[0011]
Here, in this embodiment, the auxiliary bead 5 is provided on the side of the full bead 3 of the substrate 1 that is away from the combustion chamber hole 2. The auxiliary bead 5 is a full bead, is lower than the full bead 3 of the substrate 1 and can be elastically deformed in the thickness direction, and is arranged so that the convex portion side faces the substrate 1.
When the metal gasket having such a configuration is interposed between the cylinder block and the cylinder head and tightened with the fastening bolt, the full bead 3, the auxiliary bead 5, and the peripheral edge portion 4a are compressed and deformed in the thickness direction in this order. The process is performed up to the thickness of the outer peripheral edge of the substrate 1 where the thickness does not change. At the end of tightening, the surface load is concentrated on the thickest peripheral edge 4a, and the maximum load is applied to the peripheral edge of the cylinder bore where the sealing conditions are most severe, thereby suppressing the vibration amplitude of the engine and the cylinder bore end. A primary seal with a high surface pressure with respect to the peripheral edge of the part is made, and the full bead 3 and the auxiliary bead 5 are prevented from being bent completely. Further, the seal pressure due to the elastic repulsion force of the compressed and deformed full bead 3 and the elastic repulsion of the auxiliary bead 5 are provided. The secondary seal by the full bead 3 and the tertiary seal by the auxiliary bead 5 are performed on the high-temperature and high-pressure combustion gas by the sealing pressure by the force, and the cooling water from the water hole 7 to the full bead 3 side by the seal pressure by the auxiliary bead 5 Intrusion is prevented.
[0012]
Further, as described above, the peripheral edge portion 4a of the shim plate 4 has a thickness in the vicinity of the bolt hole 6 of the fastening bolt having a large fastening force at the time of bolt fastening, which is smaller than a thickness between the bolt holes 6 having a small fastening force. Since the plate thickness is raised along the circumferential direction of the combustion chamber hole 2, the seal pressure in the circumferential direction at the peripheral edge of the cylinder bore can be made uniform.
[0013]
In the above-described embodiment, the case where the auxiliary bead 5 is a full bead is taken as an example. However, the auxiliary bead 5 may be a step bead instead.
In the above embodiment, the case where the end portion of the shim plate 4 on the combustion chamber hole 2 side is folded and the number of the peripheral edge portions 4a in the thickness direction is taken as an example. There is no need, for example, an annular shim plate may be laminated on the end of the shim plate 4 on the combustion chamber hole 2 side and joined by welding or the like.
[0014]
Next, with reference to FIGS. 4-8, the metal gasket which is other embodiment of this invention is demonstrated.
4 and 5, the thickness of the peripheral edge portion 4a of the shim plate 4 is reduced in the vicinity of the bolt hole 6 of the fastening bolt having a large fastening force at the time of bolt fastening, and the fastening force is small as in the above embodiment. The bolt holes 6 are thickened, and the folding width of the peripheral edge portion 4a of the shim plate 4 is narrowed in the vicinity of the bolt holes 6 of the fastening bolt having a large fastening force at the time of bolt fastening, and between the bolt holes 6 having a small fastening force. In this embodiment, the width of the peripheral edge portion 4a is gradually increased from the vicinity of the bolt holes 6 to the space between the bolt holes 6 along the circumferential direction of the combustion chamber holes 2. An inflection is added to the width. Thereby, the circumferential and radial seal pressures at the peripheral edge of the cylinder bore end are made uniform. Further, the folding width of the peripheral edge portion 4a of the shim plate 4 is narrowed in the vicinity of the bolt holes 6 of the fastening bolts and widened between the bolt holes 6 having a small tightening force, so that the plate thickness in the vicinity of the bolt holes 6 is formed by press molding. When thinning, it can be easily deformed in the thickness direction.
[0015]
FIG. 6 shows an example in which shim plates 4 are arranged between two upper and lower substrates 1, and the full beads 3 of the upper and lower substrates 1 are arranged so as to face each other. FIG. 7 shows an example in which shim plates 4 are arranged between two upper and lower substrates 1, but the concave sides of the full beads 3 of the upper and lower substrates 1 are arranged to face each other. FIG. 8 shows an example in which a shim plate 4 and a thickness adjusting sub-plate 10 are arranged between two upper and lower substrates 1. The full beads 3 of the upper and lower substrates 1 are arranged so that their convex portions are opposed to each other. In the range corresponding to the width of the peripheral edge portion 4 a of the shim plate 4, a step of approximately 1/3 to 1/2 of the plate thickness is provided according to the thickness of the shim plate 4, and the step recess 11 of the sub plate 10 is provided. It is the example which fitted the peripheral part 4a.
[0016]
【The invention's effect】
As is apparent from the above description, according to the first or second aspect of the invention, an effect that a sufficient sealing performance can be obtained over the entire circumference of the combustion chamber hole is obtained.
According to the invention of claim 3, in addition to the invention of claim 1 or 2, the effect that the circumferential seal pressure at the peripheral edge of the cylinder bore can be made uniform is obtained.
[0017]
In the invention of claim 4, in addition to the invention of any one of claims 1 to 3, the effect that the radial seal pressure at the peripheral edge of the cylinder bore can be made uniform is obtained.
[Brief description of the drawings]
FIG. 1 is a plan view of a main part for explaining a metal gasket as an example of an embodiment of the present invention.
2 is a cross-sectional view taken along the line II of FIG.
FIG. 3 is an enlarged cross-sectional view of a shim plate.
FIG. 4 is a plan view of an essential part for explaining a metal gasket according to another embodiment of the present invention.
FIG. 5 is an enlarged cross-sectional view of a shim plate.
FIG. 6 is an explanatory cross-sectional view for explaining a metal gasket according to another embodiment of the present invention.
FIG. 7 is an explanatory cross-sectional view for explaining a metal gasket according to another embodiment of the present invention.
FIG. 8 is an explanatory cross-sectional view for explaining a metal gasket according to another embodiment of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Substrate 2 ... Combustion chamber hole 3 ... Full bead (substrate bead)
4 ... Shim plate 4a ... Peripheral part 5 ... Auxiliary bead 6 ... Bolt hole 7 ... Water hole

Claims

The substrate is provided with a bead around the combustion chamber hole, and a shim plate laminated on the substrate. The substrate is interposed between the joint surfaces of the cylinder block and the cylinder head and tightened with a fastening bolt, thereby joining the joint. In a metal gasket that seals between the faces,
The shim plate is formed thinner than the substrate,
The shim plate is disposed around the combustion chamber hole so as to cover the bead of the substrate, and the end of the shim plate on the side away from the combustion chamber hole is located inside the outer peripheral edge of the substrate and the bolt hole. Position to,
In addition, the shim plate is configured such that the thickness of the peripheral edge, which is the peripheral edge of the combustion chamber hole side, is maximized by increasing the number of sheets in the thickness direction at the end of the shim plate on the combustion chamber hole side. An auxiliary bead is provided on a side of the substrate bead that is away from the combustion chamber hole and does not overlap with the substrate bead in the substrate thickness direction, and the auxiliary bead has an endless shape in the combustion chamber hole of the substrate. And so as to be surrounded by, and set lower than the beads provided on the substrate,
A metal gasket characterized in that when it is interposed between the joint surfaces of a cylinder block and a cylinder head and tightened with a fastening bolt, the bead of the substrate, the auxiliary bead, and the peripheral edge are compressed and deformed in this order.

2. The metal gasket according to claim 1, wherein the end portion of the shim plate on the combustion chamber hole side is folded back so that the number of the end portions in the thickness direction is two.

The metal gasket according to claim 1 or 2, wherein the thickness of the end portion of the shim plate on the combustion chamber hole side is changed along the circumferential direction of the combustion chamber hole.

The metal gasket according to any one of claims 1 to 3, wherein a width of an end portion of the shim plate on the combustion chamber hole side is changed along a circumferential direction of the combustion chamber hole.