Nok Corporation

Advics Co., Ltd.

Eagle Industry Co., Ltd.

Shinya Nakaoka

Isao Tanji

Takeshi Watanabe

Kazuya Aihara

Kuniaki Miyake

Eiji Mizutani

Masaru Ito

Tomoo Ogura

Tomonari Saito

Takanori Anzai

Shota Toma

Ryoko Saito

Takaaki Yasudomi

Taisuke Yamada

Kenji Sasaki

Tatsuhiro Arikawa

Junichi Nakayama

Nobuyuki Eguchi

Hiroyuki Nikamoto

Yuki Takao

Takashi Ota

Noriyuki Hosoi

Naohiro Jotaki

Noriyuki Shinbo

Kazuhiro Yamamoto

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

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 order to prevent gaps from occurring in corner sections in a section where three surfaces are joined together, comprising the combination of a housing, grommet and cover, or the like, thereby improve sealing, a seal structure, which is provided with a housing in which a notch-shaped grommet-mounting section is disposed, a grommet, a cover and a metal substrate gasket, is provided, wherein the grommet is provided with a seal projection, and the seal projection forms a protruding section due to a portion of the seal projection protruding toward the metal substrate gasket when the seal projection makes intimate contact with the inner surface of the grommet-mounting section. The metal substrate gasket is provided with two seal lines and a groove-shaped recess between the seal lines. When nipped, the protruding section of the seal projection is tightly compressed inside the groove-shaped recess in the metal substrate gasket.

Seal structure

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.

An outer gas type or inner gas type accumulator has a mechanism for reducing a pressure difference generated when liquid in a liquid chamber and gas expand thermally at a zero-down time, the pressure difference between the inside and outside of a bellows is reduced to suppress abnormal deformation of the bellows, a movable plate supported by a spring is provided at the bellows cap side of an oil port, the movable plate is supported by the spring and away from a seal in normal operation, the movable plate is pushed by the bellows cap and contacts with the seal while elastically deforming the spring, in a zero-down state, and when the liquid and the gas expand thermally in the zero-down state, the bellows cap moves to a position where the liquid pressure and the gas pressure balance, while the movable plate keeps contact with the seal.

Accumulator

A PTFE resin composition, which comprises PTFE resin, and metal carbide powder having a Vickers hardness of 1,200 HV, or more, and which preferably further contains an inorganic filler other than the metal carbide powder, for example, carbon fibers, glass fibers, etc., has an improved abrasion resistance, when molded into resin seal rings, etc., by reducing a self-abrasion amount of the resin against hard mating metals having a rough surface (Rz of about 6.3 to about 9.0 according to JIS B0601-1994), and by polishing the mating material roughness rapidly.

PTFE resin composition

To restrain abnormal deformation of a bellows due to a pressure difference between the inside and outside thereof, an outside gas type accumulator includes a pressure difference regulation mechanism () having a movable plate () supported by a coil spring () on the oil port () side of a bellows cap (), the plate () moves together with the cap () in a state of being supported by the spring (), during normal operation, the plate () moves together with the cap () to be brought into contact with a seal () at zero-down time, and the plate () keeps contact with the seal () and the cap () moves to a position where liquid pressure and gas pressure balances while compressing the spring () when the liquid and the charged gas expand thermally.

To prevent abnormal deformation of a bellows, an accumulator has a regulation mechanism for reducing a pressure difference generated when liquid sealed in a liquid chamber and charged gas are thermally expanded at a zero-down time, a seal plate is arranged in an inner peripheral side of a bellows floating end, an elastically deformable thin plate is bonded to the seal plate, an outer peripheral portion of the thin plate is bonded to the bellows floating end, the seal plate is away from a seal at a time of a steady operation, the seal plate contacts with the seal at a zero-down time, and the thin plate is elastically deformed to make liquid pressure balance with gas pressure while the seal plate being kept in contact with the seal when the liquid and gas are thermally expanded.

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Shizuoka, Japan

Shinya Nakaoka