Nok Corporation

Isao Tanji

Shinya Nakaoka

Kazuya Aihara

Takeshi Watanabe

Masaru Ito

Takanori Anzai

Shota Toma

Ryoko Saito

Tokunori Yanagi

A gasket, to be installed between a first housing and a second housing, includes a first loop-shaped portion in a loop shape, a second loop-shaped portion in a loop shape that is positioned at a radially inner side of the first loop-shaped portion, with a first gap between the first loop-shaped portion and the second loop-shaped portion, and a first connector portion connecting the first loop-shaped portion and the second loop-shaped portion in a part of the first gap.

Gasket

An upper gasket member includes an upper base portion of an annular flat plate, an upper outer periphery portion diagonally extending to an upper side from an outer periphery edge portion of the upper base portion, and an upper outer periphery side annular portion of an annular flat plate extending in an extension direction of the upper base portion from an outer periphery edge portion of the upper outer periphery portion. Further, a lower gasket member includes a lower base portion of an annular flat plate, a lower outer periphery portion diagonally extending to a lower side from an outer periphery edge portion of the lower base portion, and a lower outer periphery side annular portion of an annular flat plate extending in an extension direction of the lower base portion from an outer periphery edge portion of the lower outer periphery portion.

Gasket and sealing structure

A metal gasket includes: a straight section provided with a bolt hole; a bead section raised from an inner peripheral edge of the straight section toward one side of the direction of the thickness of the gasket; and a bent section bent from an outer peripheral edge of the straight section toward the other side of the direction of the thickness of the gasket. When metal gasket is compressively sandwiched by a pair of housings, bead section elastically deforms to decrease height, and straight section elastically deforms, whereby the inner peripheral edge of the straight section contacts one of the housings, the outer peripheral edge of the straight section contacts the other housing, and the bent section contacts the one of the housings. A gasket installation determination projection is part of the periphery and provided on the outer peripheral edge of the bent section or of the straight section.

Metal gasket

A metal gasket exhibiting an excellent seal effect on external foreign matter, such as salt water, and having low reaction force when required sealing pressure is low. The metal gasket, which is sandwiched between a pair of housings to seal the internal space of the housings and prevent entrance of external foreign matter between the housing and the gasket, has a straight portion, where the entire surface from an inner peripheral edge portion to an outer peripheral edge portion is a planar shape. A bent bead portion, directed obliquely outward and contacting one of the housings, is integrally provided in the outer peripheral edge portion of the straight portion. The bent bead portion functions as both an inward seal sealing the internal space and an outward seal preventing the entrance of external foreign matter between the housing and the gasket.

It is an object of the present invention to provide a sealing structure for a casing that can reduce the number of used gaskets and achieve further weight reduction, with the sealing function of the gaskets secured. The object is solved by including: a casehaving an opened top; a coverattached to the top of the caseto form a fluid flow path therein; a center plateinterposed between the caseand the coverand partitions an inner space into the side of the caseand the side of the cover; and a gasket, which is disposed between the caseand the cover, and forming the center plateso as to have a size that is within an inner peripheral side relative to a sealing lineof the gasketand stacking this center plate on the gasket, and attaching the coverto the top of the casewith the stacked gasketand center platesandwiched there between to compress the gasketwith the mutual butting surfaces between the caseand the cover

Sealing structure for casing

The present invention has an object of providing a sealing structure for a casing that suppresses the deformation of a center plate of a laminated gasket on a partition wall and ensures the compression amount of a bead on the partition wall, without the center plate being thickened. The object is achieved by a sealing structure including: a case, the interior of which is partitioned by a partition wallinto an upstream chamberand a downstream chamber; a cover, which forms a flow path for a fluid that causes the upstream chamberand the downstream chamberto be communicated inside; and a laminated gasket, in which a first gasket, a center plate, and a second gasketare laminated, and that is provided between a butting surfaceof the caseand a butting surfaceof the cover, in which the first gasketand the second gasketrespectively include beadsandalong the butting surfacesand, and the first gasketand the center platerespectively include partition-wall sealing portionsandalong the partition wall, the partition-wall sealing portionof the first gasketincludes the beads, and the coveris provided with a contact portionthat applies a contact force to the partition-wall sealing portionof the center plate

The present invention addresses the problem of providing: a metal gasket capable of limiting the loss of axial bolt fastening force even if a peripheral creased section is formed as an anti-saline intrusion measure; and a metal gasket, which has relatively small curved sections with a radius of curvature of not more than 20 mm on the outer edge and which is capable of limiting loss of axial bolt fastening force even when a peripheral creased section is formed over the entire perimeter of the metal gasket as an anti-saline intrusion measure. Said problem is solved by a metal gasket, which is disposed between the abutting surfaces of two members and has, on a metal base plate: bolt holes into which bolts are inserted; a bead that is to the inside of the bolt holes and is for sealing between the abutting surfaces; and a peripheral creased section configured by bending the perimeter of the metal base plate in one direction so that no gap in which saline can accumulate is formed between the abutting surfaces. The peripheral creased section has areas formed by gradually changing bend length in the gasket circumferential direction so that loss of axial bolt fastening force when compressed by bolts is limited.

In a tabular metal gasket having a plurality of bolt holes, a seal bead is provided between bolt holes which are adjacent to each other, one end of the seal bead is connected to the one bolt hole and the other end of the seal bead is connected to the other bolt hole. The seal bead is formed into a gradually changing shape in which a width is the narrowest at the center portion between the bolt holes and the width is gradually enlarged from the center portion between the bolt holes toward the bolt holes, and satisfies the following expression (a): D&#x3e;d&#x2267;Win which D is a diameter of a head seat surface of a fastening bolt which is inserted into the bolt hole, d is a diameter of the bolt hole, and Wis the maximum width of the seal bead.

An object is to provide a metal gasket that can form a wide contact width for a counterpart sealing face and that can achieve excellent sealing properties even when a blow hole is generated in the counterpart sealing face, and the object is achieved by a metal gasket having a bead portion to be in contact with a counterpart sealing face to form a sealing portion, formed on a gasket main body. The bead portion includes an arc portion that is convex toward the counterpart sealing face and hem-rising portions that each obliquely rise from the gasket main body toward the arc portion, on both hems of the arc portion. A connection portion between the arc portion and the hem-rising portion is formed to be convex toward a convex side of the bead portion. Plastic distortion for an overall width of the arc portion is lower than that of the connection portion. A contact pressure distribution in the arc portion in a compression state has a shape that is flat and wide in a width direction of the arc portion.

A seal structure has one metal gasket arranged between a pair of casings. The metal gasket is provided with a planate outer peripheral portion and a bead portion which is formed by rising up from an inner peripheral end portion of the outer peripheral portion, and is arranged so that the bead portion comes into contact with the one casing, and the outer peripheral portion comes into contact with the other casing. The bead portion elastically deforms so as to reduce its height and the outer peripheral portion elastically deforms on the basis of the elastic deformation of the bead portion, when the metal gasket is pinched by the pair of casings, and a leading end of the outer peripheral portion comes into contact with one casing at this time, whereby any gap in which salt water stays is not formed between one casing and the metal gasket.

Seal structure using metal gasket

Provided is a seal bead structure of a gasket capable of reducing the reactive force generated in a common bead portion provided between multiple through-holes and thereby capable of achieving a stable sealing function by means of aligning the compression property over the entire bead. In order to achieve this, two through-holes are provided in a row in the flat portion of a metal gasket, with one seal bead provided on the edge of one through-hole, the other seal bead provided on the edge of the other through-hole, and a common bead portion for the both seal beads provided in the intermediate position between the both through-holes, the common bead portion having a two-stage half bead shape in which the half beads are formed on two stage in the same direction.

Seal bead structure of gasket

A seal structure has a metal gasket arranged between a pair of casings. The metal gasket is provided with a bead portion in an inner peripheral side of a planate outer peripheral portion, and a bent portion in an outer peripheral side. When the metal gasket is pinched by a pair of casings, the bead portion elastically deforms so as to reduce its height and the outer peripheral portion elastically deforms on the basis of the elastic deformation of the bead portion, and comes into contact its outer peripheral end portion with one casing, whereby any gap in which salt water stays is not formed between one casing and the outer peripheral portion, and the bent portion comes into contact with the other casing, whereby any gap in which the salt water stays is not formed between the other casing and the outer peripheral portion.

Growing community of inventors

Fukushima, Japan

Isao Tanji