US 4,449,717 AGranted

Sealing mechanism for bearings

AssigneeMutsubishi Rubber Co., Ltd.

InventorsMichio Kitawaki, Masao Annaka

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Abstract

For a bearing mechanism, a pair of oil seals are installed within an outer cylindrical housing and elastically encircle a rotating or reciprocating shaft extending concentrically through the housing. Each of the oil seal is made of rubber or synthetic resin and has a prop ring made of steel wire extending underground through a radially outer portion of the oil seal. The prop ring is partly cut out and thus provides a radially outwardly directed elasticity for close adhesion to the inner surface of the housing. The radially outer portion of the oil seal extends in a radially inward direction to form an oil sealing lip and a dust sealing lip, with a narrow dog-legged portion at an intermediate portion of the oil seal which permits the oil seal to be flexible in a radial direction. An additional seal having substantially a similar elements and structure may be installed as a dust seal.

Claims11

Dependent claims

A sealing mechanism comprising a cylindrical housing adapted to concentrically surround an axially extending shaft and a bearing to which a lubricating oil is supplied to apply a lubricating effect to said shaft, and a pair of elastic oil seals ringedly interposed between said housing and said shaft adjacent to said bearing for preventing leakage of said lubricating oil from said bearing, each of said oil seal being characterized in that:

(a) an elastic prop ring is buried in and extends through a radially outer portion of said oil seal, said prop ring being partly cut out and thus providing a radially outwardly directed elasticity;
(b) one of annular side surfaces of said oil seal has a V-shaped annular groove which is cut out to a depth greater than half a width of said oil seal;
(c) the other annular side surface of said oil seal has a W-shaped annular groove which cooperates with said V-shaped groove to form a dog-legged portion integrally with said radially outer portion, said dog-legged portion improving an elasticity of said oil seal in a radial direction;
and
(d) a radially inner portion of said oil seal comprises an oil sealing lip formed integrally with said dog-legged portion.

2 more elements

Dependencies are inferred from the claim text.