Nok Corporation

Masamichi Kishiro

Nobuhiro Nishimura

Tatsuya Mori

Hiroshi Onodera

Naoki Meguro

Takayuki Oyama

Yu Yamaguchi

Toshiaki Yamauchi

A sealing device includes a seal housing disposed between a cylinder and a rod, an inner seal disposed between the rod and the seal housing, the inner seal being in contact with the rod, and an outer seal disposed between the inner seal and the seal housing, the outer seal being in contact with both the inner seal and the seal housing, in which one of the outer seal and the seal housing has a contact face that is in contact with the other of the outer seal and the seal housing, and the contact face has a concave portion.

Sealing device

An elastic body includes an annular main body portion to be disposed in an annular gap, a seal lip portion extending from a portion, closer to an object to be sealed, of the main body portion and being to be in contact with an inner member, a flange portion extending outwardly from an end, opposite to the object to be sealed, of the main body portion and including a first side closer to the object to be sealed, the first side being to be in contact with an outer member, a side lip portion extending from the end opposite to the object to be sealed in a direction away from the object to be sealed, and a projecting portion formed circumferentially on a second side, opposite to the object to be sealed, of the flange portion. The side lip portion has a back surface configured to be in contact with the projecting portion in response to the side lip portion being pressed by a mating member disposed opposite to the object to be sealed.

A sealing device that is adapted to be disposed between a reciprocating shaft and an inner peripheral surface of a shaft hole in which the reciprocating shaft is disposed, and that separates an oil side from an atmosphere side, includes an annular oil seal made of a resin, an oil-side rigid ring made of a metal, an elastomeric annular dust seal, and an atmospheric-side rigid ring made of a metal. The oil seal has an oil lip adapted to be in slidable contact with the reciprocating shaft and is formed of a resin having a glass transition temperature of 80 degrees Celsius or higher. The oil-side rigid ring is disposed around the oil seal and supports the oil seal. The dust seal is disposed on the atmosphere side of the oil seal and has a dust lip adapted to be in slidable contact with the reciprocating shaft.

A sealing device seals a rod having a cylindrical part and a cylindrical guide that guides reciprocation of the rod in an axial direction of the rod. The sealing device includes an elastic ring formed of an elastic material, and a rigid ring formed of a rigid material fixed to the elastic ring for reinforcing the elastic ring. The elastic ring includes a lip with which an outer peripheral surface of the rod is in slidable contact. The rigid ring includes a rigid-ring cylindrical part located radially outside an end portion of the guide. The rigid-ring cylindrical part includes multiple hook hasps engaged into at least one recess formed on an outer peripheral surface of the guide. Each of the multiple hook hasps includes a root portion and a distal end portion located radially inward of the root portion and fitted into the recess. A thin portion is formed at the root portion of the hook hasp, the thin portion being thinner than other parts of the hook hasp.

Sealing device and manufacturing method therefor

[Problem] To provide a sealing device having high pressure resistance and durability for a reciprocating shaft. [Solution] A sealing device comprising an oil seal member and a dust seal member. The oil seal member and the dust seal member each comprise a rigid ring provided inside a shaft hole and an elastic ring attached to the rigid ring, wherein the elastic ring has formed thereon a lip that slidably contacts a reciprocating shaft. The rigid ring of the dust seal member is detachably fitted in the rigid ring of the oil seal member. The sealing device further comprises another rigid ring provided between the elastic ring of the oil seal member and the elastic ring of the dust seal member in a direction parallel to the axial direction of the reciprocating shaft. This rigid ring is detachably fitted in a concave portion formed radially inward of the rigid ring of the dust seal member and reinforces the elastic ring of the dust seal member.

A valve stem seal with significantly improved sealing performance while improving workability when fitting the valve stem seal to a valve stem guide. An inner peripheral surface of a fitting sectionB is provided with a plurality of annular seal protrusions which respectively include first inclined surfacesandeach having a diameter that increases from a radially inward tip toward a seal sectionA side, and second inclined surfacesandeach having a diameter that increases from a radially inward tip toward a side opposite to the seal sectionA. The first seal protrusionwhich is closest to the seal sectionA is configured so that an inclination of the second inclined surfaceis smaller than that of the first inclined surface, and the second seal protrusionwhich is farthest from the seal sectionA is configured so that an inclination of the first inclined surfaceis smaller than that of the second inclined surface

Valve stem seal

A valve stem seal hermetically seals a space formed between a valve stem of a valve which establishes and interrupts communication between a cylinder and a port and a valve guide into which the valve stem is inserted in a reciprocally movable manner, wherein the valve stem seal includes: a reinforcing ring formed into an annular shape centered about an axis, and extending in a radial direction of a ring of the reinforcing ring; and an elastic body portion formed into an annular shape centered about the axis, attached to the reinforcing ring, and including a seal lip which abuts on the valve stem.

Growing community of inventors

Fukushima, Japan

Masamichi Kishiro