Bearing device for wheel

Abstract

A bearing device for wheel includes: a rolling bearing that includes an inner ring, outer ring, rolling elements between the inner and outer rings, and an inner sealing member; a hub wheel that includes a flange into and a cylindrical shaft to which the rolling bearing is assembled; and an outer sealing member mounted on an end of an outer periphery of the outer ring so as to close a clearance defined between the outer ring and the flange. The outer sealing member includes a main cylindrical body having a fixed base part fixed to the outer ring, and an elastic sealing lip that is integrally formed along the main cylindrical body and is elastically press-contacted to the flange, and the main cylindrical body is formed so as to have a tapered cylinder shape of which the diameter is gradually changed toward the tip from the fixed base part.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a sectional side view showing a wheel hub unit as a bearing device for wheel according to a first embodiment of the invention.

FIG. 2 is an enlarged sectional side view of the lower part of an outer sealing member in the wheel hub unit according to a first embodiment of the invention.

FIG. 3 is a sectional side view showing a wheel hub unit as a bearing device for wheel according to a second embodiment of the invention.

FIG. 4 is an enlarged sectional side view of the lower part of an outer sealing member in the wheel hub unit according to a first embodiment.

Claims

1. A bearing device for wheel comprising: a rolling bearing that includes an inner ring, outer ring, rolling elements disposed between the inner and outer rings, and an inner sealing member assembled in an annular clearance defined between the inner and outer ring to seal the annular clearance;a hub wheel that includes a flange to which a wheel is to be assembled and a cylindrical shaft to which the rolling bearing is assembled; andan outer sealing member mounted on an end of an outer periphery of the outer ring located at a side of the flange so as to close a clearance defined between the outer ring and the flange, whereinthe outer sealing member includes a main cylindrical body having a fixed base part that is inserted into and fixed to the end of the outer periphery of the outer ring, and an elastic sealing lip that is integrally formed along a periphery of a tip of the main cylindrical body and is elastically press-contacted to an side of the flange, andthe main cylindrical body is formed so as to have a tapered cylinder shape of which the diameter is gradually changed toward the tip from the fixed base part.

2. The bearing device according to claim 1, wherein the outer sealing member includes a drainage hole at a lower part of the outer sealing member.

3. The bearing device according to claim 1, wherein the outer sealing member includes a reinforcement rib projecting outward in a radial direction at a terminal of the fixed base part of the main cylindrical body.

4. The bearing device according to claim 1, wherein the diameter of the tapered cylinder shape is gradually increased toward the tip from the fixed base part.

5. The bearing device according to claim 1, wherein the diameter of the tapered cylinder shape is gradually decreased toward tip from the fixed base part.