Nok Corporation

Hiroki Matsui

Hideharu Hyakutake

Masayuki Tanida

Toru Nakashima

Yusuke Kamiya

Shinya Omoto

Akira Yamaguchi

Takehiro Nakagawa

Hideyuki Furuyama

Hirotaka Mizuta

Kei Sasaki

Satoshi Yamanaka

Go Kanzaki

Tomoaki Nishimura

Shinya Takeda

Yuki Sato

Makoto Kamemura

Toshihiro Higashira

Kokichi Hamamoto

Yuya Sakano

Shinobu Munekata

Masahiko Inoue

Hisato Yonai

Kazuki Takeno

Ken Yoshikawa

Akihiro Komyo

Shiho Sato

Kenichi Kunieda

Tomoki Nishide

Hideyuki Huruyama

Tatsuhiko Watanabe

A sealing apparatus which seals an annular gap of a hole into which a shaft is to be inserted, includes a sealing apparatus body to be fitted into the hole, and a slinger to be attached to the shaft. The sealing apparatus body includes a reinforcing ring annular around an axis line, and an elastic body portion attached to the reinforcing ring and annular around the axis line. The slinger includes a flange portion extending toward an outer periphery side and annular around the axis line. The elastic body portion includes an end-face lip extending on one side in an axis line direction, contacting the flange portion from another side in the axis line direction, and annular around the axis line. At least one groove is formed on the other side of the flange portion, and a plurality of projections are formed side by side in a circumferential direction on an inner periphery surface of the end-face lip extending in a spiral manner in a rotation direction of the shaft from the other side to the one side and being formed on an inner periphery side of a slinger contact portion of the end-face lip.

Sealing apparatus

A sealing structure with an annular pocket and a sealing device includes an annular pocket and a sealing device. The pocket is provided in a slinger, and the sealing device is attached to a housing of a differential device. The slinger is arranged on an output shaft of the differential device. A recessed part of the pocket is defined by an inner peripheral tubular portion, an outer peripheral tubular portion and a bottom portion of the slinger. The outer peripheral surface of the pocket is formed in the outer peripheral tubular portion of the slinger. The outer peripheral surface of the pocket increases in diameter toward the outside in an axis direction. A side lip of the sealing device extends in the outward direction, and an annular gap is formed between the side lip and the pocket.

Sealing structure with annular pocket and sealing device

A sealing structure with a torsional damper and an oil seal includes a damper pulley and an oil seal. The damper pulley includes, in a disk part of a hub on a front cover side, an annular projection that protrudes between the window and the boss part. The oil seal includes a side lip and a flange. The side lip extends to the inside of an annular groove of the damper pulley. The flange is opposed to the projection of the damper pulley to cover the projection so that a gap is formed between the flange and the projection.

Sealing structure with torsional damper and oil seal

A sealing structure with a torsional damper and an oil seal includes a damper pulley serving as a torsional damper and an oil seal. The damper pulley has an annular hub pocket that is recessed in the outer side direction and extends in the circumferential direction along a boss part of a hub. The oil seal includes a side lip that extends toward the outer side. An outer circumferential surface of the hub pocket increases in a diameter toward the outer side, the side lip of the oil seal does not enter inside the hub pocket, and an annular gap is formed between an outer side end of the side lip and an inner side end of the outer circumferential surface of the hub pocket.

A sealing structure allows for formation of a labyrinth structure between an oil seal and a torsional vibration damper even when the oil seal does not include a side lip. The oil sealincludes an oil lipprovided such as to be slidable on an outer circumferential surface of a tubular part, and a dust lipprovided further on an air side (A) than the oil lipand slidable on the outer circumferential surface of the tubular part. An annular memberis further provided, which is fixed to the outer circumferential surface of the tubular partfurther on the air side (A) than the dust lipand covering an outer circumferential surface of the dust lipsuch that there is a gap between the annular memberitself and the outer circumferential surface of the dust lip

Sealing structure

The purpose of the present invention is to provide a sealing device which has forward and reverse screw threads exhibiting a fluid-pumping action provided on a sliding portion of a seal lip, such that the pumping action is less susceptible to deterioration even with increasing wear on the screw threads and such that leakage of droplets from the screw threads is minimized. To achieve this, the forward and reverse screw threads which exhibit a pumping action on sealing fluid are arranged in a circle on the air-side lateral surface of the sliding portion of the seal lip. The forward and reverse screw threads each have a shape gradually increasing in thread height from the leading end of the lip to the air side. The forward screw threads and/or reverse screw threads are provided with seal protrusions for preventing leakage of droplets.

Sealing device

A sealing structure allows for formation of a side lip, as well as a labyrinth structure between an oil seal and a torsional vibration damper, even when a reinforcing ring has a short inward flange part. The sealing bodyincludes a side lipextending from near a distal end of an inward flange partradially inward and further toward an air side (A) than a dust lipto a position not as far as the outer circumferential surface of a tubular part. An annular memberis further provided, which is fixed to the outer circumferential surface of the tubular partfurther on the air side (A) than the side lipand covering an outer circumferential surface of the side lipsuch that there is a gap between the annular memberitself and the outer circumferential surface of the side lip

A sealing structure that allows for formation of a side lip, as well as a labyrinth structure between an oil seal and a torsional vibration damper, even when a reinforcing ring has a short inward flange part. The sealing bodyincludes a side lipextending from near a distal end of an inward flange partof the reinforcing ringradially inward and further toward an air side (A) than a dust lipto a position not as far as the outer circumferential surface of a tubular part. The tubular partincludes a small-diameter parton which the dust lipslides, and a large-diameter parton the air side (A). The large-diameter parthas a tapered surfaceformed on an outer circumferential surface thereof that reduces in diameter toward the air side (A). An annular gap S is formed between this tapered surfaceand an inner circumferential surface of the side lip

The invention provides a sealing device which can inhibit an external dust in an atmospheric side from intruding into a lip end, thereby inhibiting a sealing fluid leakage by trapped dust. In a sealing device inhibiting leakage of a sealing fluid in an inboard side to an atmospheric side, coming into contact with a shaft by a seal lip end and circumferentially having in an atmospheric side inclined surface of the seal lip with a plurality of screws exerting a pumping action to the sealing fluid, a three-dimensional shape for preventing the dust intrusion is provided between the screws so as to inhibit the external dust intrusion in the atmospheric side toward the lip end. The three-dimensional shape is constructed by a projection or a groove extending in a parallel direction to the lip end. The projection or the groove is connected to the screws longitudinally in both end portions.

The invention provides a sealing device constructed by combination of a slinger and a lip member, the sealing device being capable of improving a sealing performance, particularly a sealing performance against external dusts. In order to achieve the object, in a sealing device having a slinger which is installed to one member among relatively rotating two members, a lip member which is installed to the other member, and structured such that the slinger integrally has a tubular portion which is fitted to the one member and a flange portion which extends in a diametrical direction, and the lip member having an end face lip which slidably comes into close contact with the flange portion, a bent portion protruding in an axial direction toward the lip member is provided in the flange portion, and a labyrinth structure having a minute gap is provided between the bent portion and the lip member.

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

For an oil seal () having a seal lip () with a slope () at the side of sealed fluid and a slope () at the side opposite to the sealed fluid, and a screw section () provided on the slope () for pushing back sealed fluid by a pumping effect at a time of rotation, in order to achieve low torque characteristics based on fluid lubrication by increasing the thickness of an oil film on sliding surfaces, an intermediate surface () is provided between the slopes (), and an oppositely threaded screw section () for sucking the sealed fluid by a pumping effect is provided on the intermediate surface () without reaching the boundary () between the intermediate surface () and the slope (), so that a threadless region is provided in the entire circumference between the screw section () and the boundary ().

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.

Growing community of inventors

Fukushima, Japan

Hiroki Matsui