Abstract: Providing an NBR composition substantially free of containment of an insolubilized substance-generating causative substance so as to prevent generation of an insolubilized substance due to extraction by a fuel while which composition is excellent in ozone resistance, ejectability from kneader, and which composition realizes a first compression set and a second compression set which are both 46% or less. An NBR composition including a polymer obtained by mixing an acrylonitrile-butadiene rubber (NBR) with polyvinyl chloride (PVC), wherein the NBR composition is obtained without blending an insolubilized substance-generating causative substance, or, in case of blending, by blending an insolubilized substance-generating causative substance at an upper limit of 0.15 parts by weight or less, into 100 parts by weight of the polymer having a PVC content of 15.70 to 17.50 wt %.

Abstract: An annular sealing device for a shaft and housing that can maintain sealing properties under fluid pressure load when creep occurs in a cut portion due to thermal expansion and the perimeter is shortened. The sealing device includes a seal ring unit configured to fit within an annular groove in the shaft, and has, on the side thereof where the outer periphery is located, a sliding surface on which the seal ring unit slides on the housing; and a lip portion on the inner periphery of the seal ring. The lip portion of tip is disposed on the side of the annular groove where a groove bottom thereof is located, in such a way that the tip thereof is deformable in a direction in which the tip increases the distance between the seal ring unit and the groove bottom of the annular groove when under pressure.

Abstract: An elastic dust cover for a ball joint is structured such that a spherical head portion formed in one end of a ball stud is retained within a socket, a shaft in the other end of the ball stud is fastened and fixed to a knuckle, a one end large-diameter opening portion is fixed and retained to an outer peripheral surface of the socket, and the other end small-diameter opening portion is retained to the shaft. An annular step portion is formed in an inner peripheral side end portion coming into contact with the dust cover in the knuckle, a part of the small-diameter opening portion is inserted into a space formed by the annular step portion and an outer peripheral surface of the shaft, and an outer peripheral surface of the small-diameter opening portion is constrained by an inner peripheral surface of the annular step portion.

Abstract: A seal system for a reciprocating cylinder includes a buffer seal, a rod seal, and a wiper seal. The buffer seal includes a dynamic seal lip and a static lip extending from a hinge portion. The hinge portion of the static lip allows fluid to escape past the outer diameter of the seal when the rod is retracted thereby releasing any pressure build-up between the rod seal and buffer seal. The axial face portion of the dynamic seal lip includes axially extending notches therein. The notches prevent the buffer seal from sticking to the axial wall of the groove and provide a consistent path for the fluid to energize the annular groove between the static and dynamic lips during the extension phase which is necessary for the function of the seal. The back-up ring is an integrated part of the buffer seal, used to provide superior extrusion resistance.

Abstract: To minimize thermal influence when integrally forming the sealing member on a flexible wiring board, a sealing structure includes a housing, a flexible wiring board inserted therethrough, and a sealing member integrally formed with the flexible wiring board to airtightly seal a gap between the housing and the flexible wiring board, the flexible wiring board includes a base substrate made of an elastic material, an electrically conductive printed wiring layer formed on a surface of the base substrate, and a cover film covering a surface of the printed wiring layer, and the printed wiring layer which crosses the sealing member is formed as a plurality of divided print wiring layers at only a crossing region with the sealing member and its vicinity.

Abstract: A valve stem seal assembly for an internal combustion engine includes an annular rigid case disposed around a valve guide and a valve stem. An annular elastomeric body is press fit within the annular rigid case and including a radially inwardly extending seal lip in sealing contact with the valve stem. The annular elastomeric body includes a first axial end facing the valve guide and a second axial end facing away from the valve guide. The annular rigid case includes a radially inwardly extending end wall opposing the second axial end of the annular elastomeric body and including a lip support extending axially from an inner portion of the radially inwardly extending end wall and opposing a radially inner surface of the radially inwardly extending seal lip.

Abstract: 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.

Abstract: Disclosed is a method for producing an electrocast belt which method ensures long-term use of an electrocasting bath and which method enables provision of an electrocast belt having a required product quality even when an electrocasting bath that has been used in electrolysis with a large cumulative amount of electricity. The method includes a first step of producing an electrocast belt having a required product quality in an electrocasting bath of a specific composition until a predetermined period of time has elapsed; a second step of subsequently producing an electrocast belt in the same electrocasting bath; and a third step of polishing a surface of the electrocast belt produced from the second step so that the electrocast belt produced from the third step has a product quality equivalent to that of the electrocast belt produced from the first step.

Abstract: An aqueous surface-treating agent, which comprises a silicone oil aqueous emulsion, a polyurethane resin aqueous emulsion, and a silane compound represented by the following general formula: (where R1 and R2 each are an alkyl group having 1 to 4 carbon atoms, and n and m are 1?n?3 and m=3?n, respectively), and/or a hydrolyzate thereof; wherein 100 parts by weight or more of the polyurethane resin in terms of the weight of solid matters is used on the basis of 100 parts by weight in terms of nonvolatile matters of silicone oil, can prevent sticking of rubber seal materials such as O rings, etc. themselves or sticking to a metal, a resin, etc., and can reduce the friction of rubber or resin seal members at the time of sliding motion.

Abstract: A component for constituting a fuel cell having a gasket molded integrally with an MEA in which molding of the gasket is required once, the MEA requires no through hole and requires a small fastening force when the MEA is compressed. The component comprises the MEA arranged between a pair of separators and compressed when a cell is assembled; a rubber impregnated portion formed by impregnating the outer peripheral portion of the MEA with a gasket molding material, i.e. a part of rubber; a flat gasket portion composed of the rubber molded integrally on the outer circumferential side of the rubber impregnated portion; a lip formed on the flat gasket portion; and a recess as a clearance when the lip is compressed. The portion impregnated with rubber and the flat gasket portion has a thickness (d3) set equal to the thickness (d2) of the MEA when the cell is assembled.

Abstract: 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.

Abstract: A sealing structure having a gasket installed in an installation groove in one member. The gasket has a body section whose width is less than the width of the installation groove. On opposite ends, in the depth direction of the installation groove, there is provided a pair of seal surfaces that contact a surface of another member and the bottom of the installation groove. The bottom surface of the installation groove is a curve that is deepest at its center in the width direction of the groove. On the gasket body section, on the side corresponding to the bottom of the installation groove, there is formed a pair of groove bottom-side projections extending along the longitudinal direction of the gasket with the seal surface between the projections, projecting from opposite ends in the width direction of the body section, and coming into contact with the surface of the installation groove.

Abstract: To prevent defective molding, a base member is set between split molds of a metal mold, a molding rubber material is injected into an endless shape cavity defined between the base member and the split mold, an injection amount thereof is made such that the molding rubber material fills the cavity and thereafter flows from an air vent hole open to a confluence position in the cavity into a surplus material reservoir provided downstream but does not fill the surplus material reservoir, pressure drop due to flow resistance is caused to the molding rubber material flowing into the surplus material reservoir, and thereby pressure in the cavity is maintained to be not lower than pressure required to mold a gasket and lower than pressure causing leakage from the cavity.

Abstract: The invention provides a plate-integrated gasket which can reduce a width necessary for installing seal members provided in a plurality of plates which are laminated on each other, and can achieve an improvement of productivity. In order to achieve this purpose, in the plate-integrated gasket, one plate and the other plate are laminated on each other, an outer peripheral surface of the one plate is fitted or loosely fitted to a stepped surface which is formed in the other plate, and a seal member made of an elastic material having a rubber-like elasticity is integrally formed astride both of the one plate and the other plate, and has a fixed portion filled in a seal fixing groove which is formed between the one plate and the other plate.

Abstract: The invention provides a gasket which can be easily formed, can be highly compressed with a low reaction force, and is highly reliable. A gasket consisting of a rubber-like elastic material is mounted in a mounting groove formed in one of two mutually opposing members and is pinched between one member and another member so as to be in pressure-contact with both the members. The gasket has a body section inserted into the mounting groove, one support protrusion provided on the side of the body section which faces the bottom of the mounting groove, located on one end side of the body section in the width direction thereof, and in contact with the bottom, and a lip protrusion provided on the side of the body section which faces another member and having a tip located at substantially the center of the body section in the width direction thereof.

Abstract: A gasket made of a rubber-like elastic body attached to an attaching groove provided in at least one out of two members to seal a gap between the two members includes a first sealing surface coming into surface contact with a surface of a first member. A second sealing surface comes into surface contact with a surface of a second member. A third sealing surface comes into surface contact with a side surface of the attaching groove, and a pressure receiving groove opened to a side receiving sealing fluid pressure which is on an opposite side of the third sealing surface and provided so as to be parallel to the first sealing surface and the second sealing surface.

Abstract: Provided is a fluororubber composition which does not deteriorate workability during roll kneading, does not cause foaming during crosslinking and molding, and is capable of giving a crosslinked molded article which exhibits desired hardness and sealing property without using a reinforcing inorganic filler such as carbon black and silica. The fluororubber composition includes, relative to 100 parts by weight of a vinylidene fluoride-copolymerized, fluorine-containing elastomer copolymer having a glass transition temperature and a melting point, no reinforcing inorganic filler, 5 to 100 parts by weight of a PTFE filler, 0.5 to 10 parts by weight of a polyol crosslinking agent, 1 to 15 parts by weight of magnesium oxide, and 0.1 to 2 parts by weight of hydrotalcite. Preferably, 0.1 to 10 parts by weight of a quaternary onium salt crosslinking accelerator is further included.

Abstract: The purpose of the present invention is to provide a gasket material that is capable of preventing corrosion caused by sulfur element, can be used as a seal part for a product that is easily damaged by corrosion, such as an electronic part, and is capable of forming a tight seal under low surface pressure with a material having low rigidity and inadequate reliability such as to have a blowhole, and that can prevent reduction in bolt axial load without producing plastic flow (setting) under pressure. The purpose is achieved by a gasket material in which a foamed rubber layer having a closed cell structure is formed, via an adhesive layer, on at least one side of a metal plate, wherein the foamed rubber layer comprises a carboxyl group-modified nitrile rubber, the expansion ratio of the foamed rubber layer is 2.0 to 3.0, and the foamed rubber layer is crosslinked with an epoxy compound.

Abstract: A valve stem seal can include an elastomeric component having a first portion for having a sealed engagement with a valve stem, and a pressure relief lip engaging a valve guide. The pressure relief lip can have a sealing configuration and a venting configuration. The venting configuration can allow excess exhaust gases to vent from a combustion chamber. After the venting of excess exhaust gases, the pressure relief lip can close to the sealing configuration to prevent oil from entering the combustion chamber. The elastomeric body or the valve guide can include a pressure relief channel. The elastomeric body can also include a bumper engaging the valve guide. The pressure relief channel can be disposed in the bumper.