Abstract: A sealing device for a water pump bearing employs a seal member without an axial lip, and having only a radial lip. The sealing device includes an annular seal member which is fixed to a shoulder portion of one end in an axial direction of an outer race of a water pump bearing and an annular slinger which is positioned on a side of the one end in the axial direction with respect to the seal member and externally fixed to the outer peripheral face of a pump shaft serving as an inner race. The seal member has a section shape which is bent along a disk portion and an outer cylindrical portion of the slinger. A labyrinth seal portion is formed between the seal member, and the disk portion and the outer cylindrical portion of the slinger. Radial lips are formed on an inner periphery of the seal member.

Abstract: An antifriction bearing unit comprises a rotating shaft, an outer ring, and rolling members. The rotating shaft comprises a large-diameter shaft portion serving as an inner ring and a small-diameter shaft portion, which is hollow and has a fitting portion of increased diameter at one end thereof. The large-diameter shaft portion has an end portion fitted and fixed in the fitting portion of the small-diameter shaft portion. The fitting portion has an outward flange integral with an end thereof. The outer ring is fixedly provided with a seal member having lips slidable in contact with the flange and the outer peripheral surface of the large-diameter shaft portion, respectively.

Abstract: It is an object of the invention to provide a sealing device for a water pump bearing which can ensure excellent seal performance although using an economical seal member that is not provided with an axial lip, and that has only a radial lip. In order to attain the object, the invention provides a sealing device 8 of the following configuration. The sealing device comprises: an annular seal member 81 which is fixed to a shoulder portion 41a of one end in an axial direction of an outer race 41 of a water pump bearing; and an annular slinger 82 which is positioned on a side of the one end in the axial direction with respect to the seal member 81 and externally fitted and fixed to the outer peripheral face of a pump shaft 1 serving as an inner race. The seal member 81 has a section shape which is bent along a disk portion 82a and an outer cylindrical portion 82c of the slinger 82.

Abstract: An antifriction bearing unit comprises a rotating shaft, an outer ring, and rolling members. The rotating shaft comprises a large-diameter shaft portion serving as an inner ring and a small-diameter shaft portion, which is hollow and has a fitting portion of increased diameter at one end thereof. The large-diameter shaft portion has an end portion fitted and fixed in the fitting portion of the small-diameter shaft portion. The fitting portion has an outward flange integral with an end thereof. The outer ring is fixedly provided with a seal member having lips slidable in contact with the flange and the outer peripheral surface of the large-diameter shaft portion, respectively.