Nok Corporation

Eagle Industry Co., Ltd.

Satoshi Yamanaka

Hideyuki Furuyama

Akira Yamaguchi

Takehiro Nakagawa

Masayuki Tanida

Yasuhiro Ikeda

Kei Sasaki

Hiroki Matsui

Go Kanzaki

Hideharu Hyakutake

Shinya Takeda

Noboru Matsushima

Norimasa Hosonuma

Fangman Xu

Shinobu Munekata

Kaoru Anzue

Maiko Kawamoto

Kouichi Mizunoya

Noriyuki Wada

Hisato Yonai

Toshiki Watanabe

Ken Yoshikawa

Hiromi Sugihara

Koichi Mizunoya

Takumi Yamada

Yu Yamaguchi

Tatuhiko Watanabe

A sealing device includes a reinforcing ring having annular shape around an axis line and an elastic body part formed from an elastic body, the elastic body part being attached to the reinforcing ring and having an annular shape around the axis line. The elastic body part includes an annular seal lip and an annular side lip that is provided on an outer side of the seal lip and that extends toward the outer side. In an inner peripheral surface of the side lip on an inner periphery side, at least one circumferential groove which is a groove having an annular shape around the axis line is provided and at least one axial groove which is a groove extending along a direction of the axis line is provided. The circumferential groove and the axial groove are connected with each other.

Sealing device

A sealing device provides sealing so as to prevent a sealed fluid in a machine inner side from leaking to a machine outer side between a housing and a rotating shaft which is inserted to a shaft hole provided in the housing. The sealing device has a seal flange which is installed to an outer periphery of the rotating shaft, and a seal lip which is installed to an inner periphery of the shaft hole of the housing and slidably comes into contact with the seal flange over an entire periphery. The sealing device includes a thread groove which exerts a fluid pumping action when the rotating shaft rotates. The thread groove is provided at a position which does not intersect a contact area where the seal lip slidably comes into contact with the seal flange over the entire periphery, thereby suppressing generation of static leakage.

The invention provides a sealing device sealing so as to prevent a sealed fluid in a machine inner side from leaking to a machine outer side between a housing and a rotating shaft which is inserted to a shaft hole provided in the housing. The sealing device has a seal flange which is installed to an outer periphery of the rotating shaft, and a seal lip which is installed to an inner periphery of the shaft hole of the housing and slidably comes into contact with the seal flange over an entire periphery. The sealing device includes a thread groove which exerts a fluid pumping action when the rotating shaft rotates. The thread groove is provided at a position which does not intersect a contact area where the seal lip slidably comes into contact with the seal flange over the entire periphery, thereby suppressing generation of static leakage.

To improve durability of a seal lip () of an oil seal () in slidably contact with the peripheral surface of a shaft (), a lubricating oil supply section () for collecting adhered oil and dropping it on the shaft () is provided at a forward end portion of an installation section (), the lubricating oil supply section () has projections () formed on the inner peripheral surface of the installation section () to collect oil on the surface thereof, the surface of each projection () has a recess () for temporarily accumulating oil, guidance projections, or a slope for collecting the oil, and dams are formed on a forward end face () of the installation section () to block the oil flowing down along the circumferential direction on the forward end face () and guides the oil toward each projection ().

Oil seal

A seal lip of an oil seal is in slidable contact with a peripheral surface of a shaft. A lubricating oil supply section for collecting adhered oil and dropping it on the shaft is provided at a forward end portion of an installation section. The lubricating oil supply section has projections formed on the inner peripheral surface of the installation section to collect oil on the surface thereof. The surface of each projection has a recess for temporarily accumulating oil. Guidance projections, or a slope for collecting the oil, and dams are formed on a forward end face of the installation section to block the oil flowing down along the circumferential direction on the forward end face and guides the oil toward each projection.

A method of manufacturing a sealing device by preparing a mold for molding both a rubber-like elastic material and a resin material, the resin material having a flat washer shape, inserting an outer diameter portion of the resin material into a mold cavity of the mold, and adhesively baking the rubber-like elastic material to the outer diameter portion of the resin material together with the molding of the rubber-like elastic material. An inner diameter portion of the flat washer shape resin material is pressed by a mold part adjacent to the mold cavity in utilization of a mold clamping pressure, the pressed inner diameter portion of the resin material is bent at an elevated temperature by a mold part to form a resin lip, arranged so as to not interfere with the rubber seal lip, and the sealing device produced is separated from the mold.

Method of manufacturing a sealing device

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.

A sealing device comprising an annular support structure, a first annular sealing lip made of rubber and supported by the annular support structure, and a second annular sealing lip adjacent to the first annular sealing lip, the second annular sealing lip being made of resin and supported by the annular support structure. The first sealing lip made of rubber is located on the side to be scaled of the second sealing lip made of resin, and grease is held in a space formed by the first and second sealing lips and a shaft.

The follow-up performance to the operation of a shaft is improved by forming an annular space between a rubber seal lip formed of a rubber-like elastic material and a resin seal lip so as to prevent the resin seal lip from interfering with the rubber seal lip. The follow-up performance to the shaft is further improved by increasing the flexibility of the resin seal lip by forming a plurality of annular grooves parallel to one another to the side surface of the annular gap side of the resin seal lip. A PTFE sheet is inserted as in the form of a flat washer shape into a mold, it is adhesively baked to a first seal member formed of rubber together with the vulcanization formation, a plurality of annular grooves and a helical groove are formed to the PTFE sheet by utilizing a mold clamping pressure, and the PTFE sheet is bent at the mold separation time after the molding process.

Sealing device having an annular space between sealing lips

A sealing device including an annular support structure, a first annular sealing lip made of rubber and supported by the annular support structure, and a second annular sealing lip adjacent to the first annular sealing lip, the second annular sealing lip being made of resin and supported by the annular support structure. The first sealing lip made of rubber is located on the side to be sealed of the second sealing lip made of resin, and grease is held in a space formed by the first and second sealing lips and a shaft.

A sealing device for use in contact with a reciprocating member such as a piston rod of an automotive shock absorber has a plurality of seal lips with tips which make resilient sliding contact with the surface of the reciprocating member. Chambers are formed between the tips of adjacent seal lips. The seal lip closest to an internal fluid to be sealed is designed to facilitate flow of the fluid into the chamber between this seal lip and the adjacent seal lip, across the region of contact between this seal lip and the reciprocating member. The design may include notches or grooves formed in the seal lip closest to the seal lip or specific design of tapered surfaces of this seal lip.

Growing community of inventors

Fukushima, Japan

Satoshi Yamanaka