Nippon Gasket Company, Ltd.

Other

Kenji Kubouchi

Kunitoshi Inoue

Shigeru Kawaguchi

Hiroshi Uemura

Masahiko Miura

Kazukuni Takada

Yuji Fukui

Tadayoshi Akutsu

Yoshikazu Shinpo

Einosuke Suekuni

Kazuya Nakata

Yutaka Furuta

Naoki Ii

Kazuyuki Geshi

Shizuo Itani

Kazuhiro Nomoto

Hiroaki Okuda

Sadao Isomura

Tadaumi Matsumoto

Jin Hashioka

Takeshi Kitamura

A laminate-type metallic gasket comprising adjacent combustion chamber holes (A, A), a pair of bead substrates (,) made of an elastic metallic plate with a bead (,) formed along each of the combustion chamber holes (A, A) and first and second intermediate plates (,), in which peak portions of beads (,) are symmetrically opposite to each other, disposed between the two bead substrates (,) according to the present invention wherein a first intermediate plate (,) is provided with a step (,) having a thickness less than that of a second intermediate (,) formed along an edge portion (,) of the combustion chamber holes (A, A). The intermediate plate (,) is disposed upon an outer surface which is made of a downwardly convex surface (,) by a formation of the step (,), and an edge portion (,) of the second intermediate plate (,) being folded back between the second intermediate plate (,) and the edge portion (,) of the combustion chamber holes (A, A) of the first intermediate plate (,) to form the compensating portion (,) having a thickness larger than the total thickness of the two intermediate plates (,) at a portion, where peak portions of the beads (,) are respectively brought into contact with the first and second intermediate plates (,), around the combustion chamber holes (A, A).

Metallic gasket

This metal gasket comprises a bead base plate with first beads and a sub-plate stacked on the bead base plate. The sub-plate is made of a thick metal plate and formed with second and third beads and stepped portions. The second beads, the third beads and the stepped portions combine to form triple seal lines, which improve the sealing function. The sub-plate is formed with the second beads opposing the first beads of the bead base plate, with the high third beads formed inside the second beads around the holes and with the stepped portions formed outside the second beads around the holes. The third beads prevent ingress of burning gases to the first beads and also serve as a stopper to prevent the first beads from being flattened completely. The third beads therefore can add durability to the sealing function realized by the first and second beads, enhancing the sealing performance of the first and second beads and reliably preventing burning gases from escaping between the opposing surfaces.

Metal gasket

The metal gasket according to the present invention is formed by bead base plates comprising elastic metal plates having beads and auxiliary beads along the circumferences of holes, and an intermediate plate interposed between these bead base plates. The stoppers and stepped portions formed on the intermediate plate prevent the total compression of the beads on the bead base plates when the metal gasket is tightened, and enable the irregularity of the opposed surfaces of a cylinder head and a cylinder block to be offset. The auxiliary beads provided on the bead base plates display the sealing performance with respect to the beads and minimize the dead spaces around the holes.

A metal gasket comprising an elastic metal plate including beads formed around cylinder bore holes of a multiple-cylinder engine, wherein each bead comprises an independent bead formed around each hole, a common bead between an adjacent pair of holes and junction beads connecting the independent bead and the common bead. The metal gasket controls a spring constant at the junction beads to a suitable value by specifying the shape of the junction beads, reduces a peak value of a face-to-face pressure at the junction beads, reduces also drop of the face-to-face pressure occurring in the junction beads and at their boundary, and makes uniform the face-to-face pressure in the vicinity of the junction beads.

This metal gasket comprises a pair of bead plates on which beads are formed so as to extend along the circumferences of combustion chamber holes, and an intermediate plate interposed between the bead plates. The intermediate plate is provided on the parts thereof which are closer to the combustion chamber holes than to the beads on the bead plates with stopper portions comprising stepped portions. These stopper portions constitute compensation portions for the beads on the bead plates. The compensation portions prevent a total compression of the beads on the bead plates when the metal gasket is tightened, offset the irregularity of opposed surfaces of a cylinder head and a cylinder block, improve the sealability with respect to the beads, and protect the beads against corrosion and compression.

Metal gasket with stepped intermediate plate

A metal gasket for a cylinder head includes a superposed assembly of an elastic metal base plate having a plurality of beads formed along a plurality of juxtaposed holes for combustion chambers, an elastic metal adjusting plate having a plurality of beads formed along a plurality of juxtaposed holes for combustion chambers, and a grommet having a plurality of juxtaposed holes for combustion chambers which are smaller in diameter than the holes in the base and adjusting plates. The grommet is folded about the edges of the holes in the adjusting plate lying between the base plate and the grommet in intimate contact therewith, so that the holes in the base and adjusting plates and the grommet may be aligned to form a plurality of bores. The bead on the base plate is formed as a full bead between every two adjoining holes and as a half bead around the remaining edge of each hole, while the bead on the adjusting plate is a full bead along the entire edge of each hole, so that the bead on the base plate may extend over the bead on the adjusting plate between every two adjoining bores.

Laminated metal gasket having a varying bead structure, thickness, and

This metal gasket for chain case-carrying engines is capable of reliably preventing the entry of an oil into height different parts, which occur on abutting surfaces of a cylinder block and a chain case, even when the oil deposited on the chain case scatters during a movement of a chain, and improving the reliability thereof owing to its durability. This metal gasket has first and second elastic metal plates provided with beads extending along an opening, in which the chain moves, and an intermediate plate provided with bores packed with seal members for sealing the height different parts occurring at the abutting surfaces of the chain case and cylinder block. The second elastic metal plate is provided with recesses formed by cutting out the portions thereof in which the seal members are positioned.

Metal gasket for chain case-carrying engines

A metal gasket comprising an elastic metal plate including beads formed around cylinder bore holes of a multiple-cylinder engine, wherein each bead comprises an independent bead formed around each hole, a common bead between an adjacent pair of holes and junction beads connecting the independent bead and the common bead. The metal gasket controls a spring constant at the junction beads to a suitable value by specifying the shape of the junction beads, reduces a peak value of a face-to-face pressure at the junction beads and makes uniform the face-to-face pressure in the vicinity of the junction beads.

The exhaust manifold gasket according to present invention consists of a pair of beaded plates provided with beads extending along the circumferences of exhaust holes therein, and a piled plate assembly inserted between these beaded plates. The piled plate assembly consists of a pair of flat plates, and a refractory sheet member disposed between these flat plates and containing a core plate therein. The refractory sheet member is formed out of a material having a high thermal resistance, excellent heat insulating characteristics and a high compression resiliency at a high temperature, such as a mica material. Accordingly, this exhaust manifold gasket has an improved compression resiliency at a high temperature and an improved sealability at a high temperature, and is capable of properly cutting off the transfer of heat.

Exhaust manifold gasket

The metallic gasket consists of a first elastic metallic plate having beads and folded portions and a second elastic metallic plate having beads, laminated on each other. The folded portions are formed by bending the plate alone the circumferences of cylinder bore holes, and the beads are formed on the portions of the plate spaced from the circumferences of the cylinder bore holes at a predetermined distance in the radially outward direction thereof, whereby double annular seal portions are formed. The projecting portions of the beads on the second elastic metallic plate are fitted in or brought into contact with the recessed portions or projecting portions of the beads on the first elastic metallic plate. The spring constant of the gasket becomes equal to the sum of those of the two plates, and this enables the stress carried by the plates to be lessened, and the durability of the gasket to be improved. It is also possible to reduce the width of the parts of the beads which are between the cylinder bore holes and use such a gasket suitably for an engine in which the distance between cylinder bores is small.

At the portions of the metallic gasket according to the present invention which are around perforations the inner diameter of which is smaller than that of holes for combustion chamber, the thickness of at least the folded portions and the portions of an elastic metallic plate on which these folded portions are laminated are reduced to a level in the range from a level not higher than that of the thickness of said metallic plate to a level not lower than that of a half of the thickness of said metallic plate. These thickness-reduced portions of the metallic plate are bent onto the bead-ridge-carrying side thereof to form folded portions, whereby the thickness of the folded portions is reduced to provide a difference in height between the folded portions and the bead-surrounding portions of the metallic plate. The metallic plate is heat treated after the folding step has been completed, to regulate the hardness of the metallic plate.

Metallic gasket and method of manufacturing the same

This invention provides a metal gasket and its production method which prevents damage to folded portions by fold-machining and damage to metal materials after fastening, and expands the range of selection of materials for elastic metal plates, by reducing the thickness of a predetermined region of a elastic metal plate at which folded portions are to be formed. The thickness of the folded portion of the elastic metal plate is reduced from the folding side in an inner region of folded base portions and in regions in which folded free ends are positioned. Bend-machining is made gently at the folded base portions subjected to fold-bend machining, and the folded base portions each have a gap there-inside. The folded free ends do not come into contact with the elastic metal plate due to recessed surfaces. Accordingly, cracks and wrinkles do not occur at the folded base portions, and the folded free ends do not leave friction traces on the elastic metal plate.

Metal gasket and production method thereof

In the metallic gasket according to the present invention, beads are formed on the circumferential portions of the first cylinder bore-aligned holes in the base member, and folded portions are formed on the auxiliary member by merely folding back the inner edge sections of the second cylinder bore-aligned holes therein so as not to embrace the bead-carrying base member, the auxiliary member being laminated on the side of the base member from which the beads project. In this metallic gasket, the folded portions of the auxiliary member restrict the deformation of the beads to minimize the occurrence of fatigue and cracks in the beads, whereby the sealing function of the gasket is improved with uniform and proper surface pressure distribution maintained. Soft members are provided between the main portion of the auxiliary member and the folded portions thereof so as to secure proper surface pressure distribution in the metallic gasket in accordance with the rigidity of the cylinder head.

This metal gasket interposes a regulation plate having compression stop portions and beads between first and second elastic metal plates the convexities of beads of which face one another. The compression stop portions prevent complete compression of each bead and absorbs any irregularity between opposed fitting surfaces around holes for a combustion chamber. An intermediate plate having an offset portion is sandwiched between the regulation plate and the second elastic metal plate. The offset portion is shaped to a height smaller than the thickness of the compression stop portions and regulates the degree of compression of each bead.

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Hirakata, Japan

Kenji Kubouchi