Abstract: A sealing structure for a continuously variable transmission, which seals a clearance between a movable sheave and a cylinder. The continuously variable transmission may change a groove width of each pulley of the cylinder by moving a corresponding movable sheave though supply and discharge of a hydraulic pressure to and from the cylinder. The sealing structure includes an outer peripheral side seal member that is ring-shaped and disposed in a ring-shaped groove formed in one of the movable sheave and the cylinder; and an inner peripheral side seal member that is more elastic than the outer peripheral side seal member, ring-shaped, and disposed in a layered manner in the ring-shaped groove on an inner peripheral side with respect to the outer peripheral side seal member. A side of the outer peripheral side seal member where it contacts the inner peripheral side seal member is chamfered.

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: A seal ring having a more stable torque reduction effect. A seal ring is adapted to seal the annular gap between a housing and a shaft which is inserted through the shaft hole of the housing, the housing and the shaft being provided so as to be rotatable relative to each other. The seal ring is mounted in an annular groove provided in the shaft, is configured so that the seal ring is pressed, by the pressure of fluid to be sealed, against a side surface of the annular groove and against the inner peripheral surface of the shaft hole, and has a recess (14) provided in the slide region of the seal ring which slides on the side surface of the annular groove, the recess (14) being separated from the side surface of the annular groove so that a force acting against the force which presses the seal ring against the side surface of the annular groove by the effect of the pressure is generated.

Abstract: 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 (21) having a movable plate (22) supported by a coil spring (23) on the oil port (4) side of a bellows cap (8), the plate (22) moves together with the cap (8) in a state of being supported by the spring (23), during normal operation, the plate (22) moves together with the cap (8) to be brought into contact with a seal (13) at zero-down time, and the plate (22) keeps contact with the seal (13) and the cap (8) moves to a position where liquid pressure and gas pressure balances while compressing the spring (23) when the liquid and the charged gas expand thermally.

Abstract: 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 spring means is provided at the bellows cap side of an oil port, the movable plate is supported by the spring means 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 means, 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.

Abstract: To improve durability of a seal lip of a sealing device attached to a shaft hole in a housing so as to slidably contact with a shaft, the sealing device has a sealing device body integrally having a tubular fixation portion fixed to the inner periphery of the shaft hole and a seal lip in slidable contact with the shaft and an oil supply member integrally having a tubular fitting portion fitted to the inner peripheral side of the fixation portion and a flange-like oil supply portion provided so as to extend radially inward from the fitting portion, the oil supply portion is arranged at a sealing fluid side from the end of the seal lip, radially inwardly extending protrusions are provided at an inner peripheral edge of the oil supply portion, and oil transmission grooves are provided on the protrusions so as to extend toward their ends.

Abstract: A sealing device comprises a stationary-side installation ring (11) fixed to an outer stationary-side member (201), a rotation-side installation ring (12) fixed to an inner rotation-side member (202), a stationary-side lip (13) provided on the stationary-side installation ring (11) to be slidably in contact with the rotation-side installation ring (12) by its tip, rotation-side lips (14, 15) formed on the rotation-side installation ring (12) to be slidably in contact with the stationary-side installation ring (11) by their tips, a pulsar ring (17) formed of a synthetic resin or rubber-like elastic material mixed with magnetic powder on the rotation-side installation ring (12) and multipolar magnetized, and a collar portion (17a) formed on an outer periphery of the pulsar ring (17) at the outer side than the rotation-side lips (14, 15) to closely face the stationary-side member (201) or the stationary-side installation ring (11), thereby an excellent sealing ability being given.

Abstract: Disclosed is a rubber composition containing 100 parts by weight of a rubber blend comprising 99-85 by weight % of chloroprene rubber and 1-15 by weight % of chlorinated polyethylene rubber, (A) 10 to 30 parts by weight of a polyether ester-based plasticizer having a molecular weight of 450 to 650, or (B) 10 to 30 parts by weight of both of a polyether ester-based plasticizer having a molecular weight of 450 to 900 and an ester-based plasticizer having a molecular weight 350 to 500, and 3 to 10 parts by weight of two or more aromatic amine-based antioxidants. The rubber composition can simultaneously satisfy requirements for use as, for example, an automobile grease cup material, that is, heat resistance, ozone resistance, cold resistance, and adhesion to metal or resin.

Abstract: A sealing structure in which sealing is made by a seal ring installed in a dovetail groove where only an inner surface on one side of the groove is an inclined surface. In the sealing structure, the seal ring is less likely to come out of the dovetail groove, resistance of insertion of the seal ring into the dovetail is small, and particles are less likely to occur in the structure. The seal ring is formed of a rubber-like elastic material and is installed in the dovetail groove where the first inner surface on one side of the groove is inclined falling to the inside of the groove.

Abstract: Object: To provide a sliding member with a low friction coefficient in which, when fine dents are formed in a surface of the sliding member by dimpling using a laser, no hard raised portions are gerenrated, and which does not damage a mating member; and to provide a process for producing the sliding member. Solution Means: A sliding member comprising a polyamide resin and 10 to 50 wt % of a fibrous filler selected from the group consisting of carbon fibers, aramid fibers, and whiskers, and having fine dents formed in a sliding surface thereof by dimpling using a laser; and a process for producing a sliding member comprising adding 10 to 50 wt % of a fibrous filler selected from the group consisting of carbon fibers, aramid fibers, and whiskers to a polyamide resin, and forming fine dents in a sliding surface of the sliding member by dimpling using a laser.

Abstract: To prevent breakage of a sealing device having a main sealing body installed within an annular installing groove (31) formed in one member (3) to slidably and concentrically contact with the other member (2) and a backup ring (12) arranged at a non-sealing space side of said main sealing body, a height (h1±?h1) of said backup ring (12) in a facing direction of a bottom surface (31a) of said installing groove (31) to the other member (2) is greater than a facing distance (L±?L) between the bottom surface (31a) and the other member (2), and said backup ring (12) has a cross-sectional shape which is symmetrical in a thickness direction thereof, and has an easily compressible part (12a) which can be compressed to the extent of the difference (x) between said height (h1±?h1) and said facing distance (L±?L).

Abstract: [Problem] To provide a method for producing a rotary shaft seal that exhibits improved eccentricity-conforming properties, in which each of the initial characteristics, i.e., a torque reduction (reduced friction) and sealing properties attributed to reduced oil leakage (oil pump rate when the seal member slides), can be improved, and degradation of these characteristics can be inhibited even after friction and abrasion; and the rotary shaft seal. [Means for Solving the Problem] A method for producing a rotary shaft seal, including blending a peroxide crosslinking agent into a fluororubber polymer component including 95 to 40% by weight of a fluororubber terpolymer obtained by copolymerization with a perfluoroalkyl vinyl ether and 5 to 60% by weight of a liquid fluororubber polymer, to prepare a fluororubber composition, followed by crosslinking and molding the composition; and the rotary shaft seal.

Abstract: The invention provides a seal ring capable of stably leaking a sealed fluid from an inner peripheral face side. In a seal ring in which an inter-side face leak passage S3 connecting a first space S1 and a second space S2 is provided to a fitted portion of a first protruding portion 10R1 fitted in a second recessed portion 10L2 and a fitted portion of a second protruding portion 10R2 fitted in a first recessed portion 10L2, a passage communicating with an inner peripheral face side and with the inter-side face leak passage is formed when an end portion on an inner peripheral side of one cut end portion 10R and an end portion on an inner peripheral side of the other cut end portion are in contact with each other.

Abstract: A sealing device includes a stationary side installation ring fixed to a stationary side member, a rotation side installation ring fixed to a rotation side member, a stationary side lip integrally provided on the stationary side installation ring and slidably contacting the rotation side installation ring, rotation side lips integrally formed on the rotation side installation ring and slidably contacting the stationary side installation ring, and a pulsar ring for a rotary encoder integrally formed on the rotation side installation ring, and magnetized to be multipolar. The rotation side installation ring includes first and second rotation side installation rings which are attached to each other. The rotation side lips are provided on the first rotation side installation ring at a relatively inner side. The pulsar ring is provided on the second rotation side installation ring at a relatively outer side.

Abstract: In a rod sealing system, which comprises a buffer ring, a rod seal, and a dust seal, provided successively in this order from a fluid hydraulic side toward the outside in an annular clearance between two members in reciprocating motion, the buffer ring is made up of a thermoplastic polyurethane molding product obtained by subjecting a thermoplastic polyurethane molding product prepared by reaction of (A) a high molecular weight polycarbonatediol having a number average molecular weight Mn of 500-6,000, (B) an aromatic diisocyanate, and (C) a low molecular weight diol as a chain elongation agent in an NCO/OH ratio of 0.95-1.20, to heat treatment under conditions that a glass transition point (Tg) of hard phases becomes 170° C. or higher, preferably 170-230° C., and an endothermic peak area (?H) at Tg becomes 5 J/g or more, by differential scanning calorimetry.

Abstract: To prevent inverting of a mountain portion of a bellows member when a rotating shaft is angularly displaced, the boot includes a bellows member with large and small diameter mounting members. A first mountain portion nearest the large diameter mounting member rises from the large diameter mounting member. A length (L1) between a top of the first mountain portion and a bottom at the large diameter mounting member side is not more than a length (L2) between the inner peripheral position of the bottom and an end portion of an outer ring at the rotating shaft side. A first valley portion adjacent to the first mountain portion is positioned at the rotating shaft side from the end part.

Abstract: In order to secure an excellent dynamic vibration absorbing characteristic without sacrificing fixing force and improve an assembling property, a dynamic damper for a hollow rotating shaft is provided with a tube body fixed to an inner periphery of the hollow rotating shaft, a pair of end plates fixed to an inner periphery of the tube body so as to be away from each other in an axial direction, a mass body positioned between the end plates and floatingly inserted to the inner periphery of the tube body, and elastic bodies coupling the end plates and the mass body in the axial direction to each other and made of a rubber-like elastic material, whereby the elastic bodies come to shear springs with respect to a vibration in the axially orthogonal direction.

Abstract: Disclosed is a two-material composite gasket, preferably a two-material composite annular gasket, for sealing a gap between two opposing surfaces, one of the surfaces having a concave gap portion, which is to be sealed by the gasket, the gasket having an oblong cross-sectional shape and having projections on the top end and bottom end thereof, the gasket including an upper low-hardness elastomer molded part formed of vulcanized rubber having a Shore A hardness of 5 to 35, a lower high-hardness elastomer molded part formed of vulcanized rubber having a Shore A hardness of 45 to 80, and a parting line bonding the low-hardness elastomer molded part and the high-hardness elastomer molded part, the parting line being positioned so that the height of the low-hardness elastomer molded part is 5 to 40% of the height of the entire gasket.

Abstract: To improve sealing performance, a sealing device comprises an oil seal (10) mounted to a non-rotating housing (2), and a dust cover (20) mounted to a rotating body (5) outside the oil seal (10), one of the oil seal (10) and the dust cover (20) facing each other has an external seal lip (24) slidably in close contact with the other of them (10, 20) outside the slide sections (S1, S2) between the oil seal (10) and the rotating body (5), the oil seal (10) and the dust cover (20) have non-contact lips (16, 25) which are positioned outside the slide sections (S1, S2) and inside the external seal lip (24), have substantially conical tubular shapes becoming larger in diameter toward the tips thereof, and are loosely inserted to each other, and a labyrinth seal (30) is provided at the outer diameter side of the external seal lip (24).

Abstract: The process for producing gaskets includes the steps of: forming a metal core material (2) using a stainless steel plate; treating the resulting metal core material (2) with an alkali treating solution; preparing an unvulcanized rubber molded product (1); mounting the metal core material (2) treated in the treating step to the unvulcanized rubber molded product (1); and vulcanizing the rubber-molded product to thereby anchor the elastic material to the metal core material (2) without using an adhesive; characterized in that the alkali treating solution used in the step of alkali treatment includes the following components (A), (B), and (C): (A) an alkali metal hydroxide or an alkaline earth metal hydroxide; (B) an alkali metal silicate or an alkaline earth metal silicate; and (C) a carboxylate salt.