Nok Corporation

Eagle Industry Co., Ltd.

Shinobu Munekata

Yasuhiro Ikeda

Satoshi Yamanaka

Kazuki Takeno

Akira Yamaguchi

Hiroki Matsui

Toshihiro Higashira

Masayuki Tanida

Naoto Kobayashi

Go Kanzaki

Hirotaka Mizuta

Yuichi Tarukawa

Ken Yoshikawa

Kenichi Kunieda

Ichiro Yamane

Koichi Mizunoya

Hidenori Arai

Katsumi Yamashina

Masaru Watanabe

Hideyuki Huruyama

Tatsuhiko Watanabe

Mitsugu Kobayashi

Tatuhiko Watanabe

A reciprocating seal used, for example, for a shock absorber. A main seal lip has a two-step lip structure including a first lip and a second lip and a plurality of protrusions extending in the direction of the shaft are formed on a sliding contact surface of the second lip, thereby improving frictional force characteristics and, at the same time, improving sealing performance.

Reciprocating seal

To stabilize frictional force to the reciprocating shaft without affecting sealing ability, a sealing device for a reciprocating shaft comprises a main lip, a whole periphery of which slidably and tightly contacts with an outer peripheral surface of a shaftreciprocating in the axial direction; and a frictional lip, which extends to the sealed space A side from the main lipand slidably and tightly contacts with the outer peripheral surface of the shaftin the state of permitting circulation of sealed fluid, whereby the frictional force of the frictional lipis not varied by pressure of the sealed fluid, while frictional force of the main lipto the shaftis varied by the pressure, the sliding surface is lubricated with the sealed fluid, and reduction of the frictional force by abrasion can be controlled.

Sealing device for reciprocating shaft

This invention provides an oil seal that can maintain an excellent friction reduction function over a long period of time, has excellent abrasion resistance, and further has excellent sealing properties. The oil seal comprises a seal lip () formed of a rubber-like elastic material comprising a lip edge part () and an air-side slope () and a sealing fluid-side slope () provided on both sides of the lip edge part (). The air-side slope () has a coating film () on its surface. In the lip edge part () in its portion in contact with a shaft (), a sealing fluid-side rubber part (') and an air-side coating film () are simultaneously brought into contact with the shaft (). The coating film () is preferably formed of a coating agent comprising a fluororesin, a polyethylene resin, an isocyanate-modified polybutadiene resin, and a solvent.

Oil seal and process for producing the same

A sealing device for a reciprocating shaft capable of providing sufficient pressure tightness to a main lip and preventing troublesomeness of an assembling operation. The sealing device, which is interposed between a shaft and an outer peripheral member, includes a washer, a main lip integrally bonded to a sealed space side of the washer and slidably brought into close contact with an outer peripheral surface of the shaft, an auxiliary lip integrally formed in an outer peripheral side thereof, a backup ring fitted between an atmosphere side of a slidable surface of the main lip and an inner peripheral portion of the washer, and bearing the main lip from the atmosphere side and the inner peripheral side, a dust lip integrally bonded to the atmosphere side of the washer and slidably brought into close contact with the outer peripheral surface of the shaft, and an outer peripheral lip integrally bonded to an outer peripheral portion of the washer and brought into close contact with the outer peripheral member.

The present invention relates to a lip-type seal of the outer periphery rubber type having a stationary sealing portion made of rubber on the outer periphery of a reinforcing ring. In view of the fact that there is produced a gap corresponding to the rubber thickness of the stationary sealing portion between the outer periphery of the reinforcing ring and inner periphery of the seal attachment hole, the invention has an object to permit certain supporting of the reinforcing ring by means of a stop functional member by expanding the engagement area engaging with the stop functional member. More specifically, in the sealing apparatus of the invention, the engagement portion with the housing is sealed by a stationary sealing portion made of rubber attached to the outer periphery of the cylindrical portion of the reinforcing ring; the sliding portion with the shaft is sealed by sealing lips and supported by the reinforcing ring; and the reinforcing ring axially engages with the stop functional member such as a stop ring fixed to the inner periphery of the housing. In this sealing apparatus thus prevented from coming off, the reinforcing ring is provided with an engagement area expanding section which is arranged on the open-air side of the cylindrical portion, having a larger diameter than the cylindrical portion, arranged near the inner periphery of the housing, and expands the engagement area with the stop ring.

Sealing apparatus

A sealing apparatus has a metal ring having a cylindrical portion and an inward flange portion bending from the open-air side end of the cylindrical portion radially inward; a first sealing member formed integral with the metal ring, and having a first rubber-like sealing lip, and a flange-shaped interposed portion held between the inward flange position of the metal ring and the radial portion of the first sealing member. A second sealing member made of a resin material, extends from the inside-diameter end of the interposed portion axially toward the sealing liquid side, and is located in a gap between the open-air side surface of the first sealing lip and a rotary member, having the inner periphery thereof in slidable close contact with the surface of the rotary member, and regulates radial deformation of the first sealing lip. A screw pumping portion is provided to transport the liquid between the sliding surfaces to the sealing liquid side on rotation of the rotary member.

Growing community of inventors

Fukushima, Japan

Shinobu Munekata