Rolling bearing unit with tone wheel

摘要

A rolling bearing unit with tone wheel comprises an outer ring member (5a) which is stationary during use and has an inner surface formed with an outer ring raceway (7) and an inner ring member (4a) which is rotatable during use and has an outer surface formed with an inner ring raceway (3). A plurality of rolling elements (8) are provided between the outer ring raceway and inner ring raceway. A seal ring (19) is fitted and secured to the outer ring member (5a) so as to cover a gap (20) extending circumferentially between the outer ring member (5a) and the inner ring member (4a). A tone wheel (29) of magnetic plate and of a generally annular shape has a magnetic property changing circumferentially alternately with a uniform interval and is fitted and secured to the inner ring member (4a). A slinger (26) of generally annular shape and L-shaped in cross section has a radially inner cylindrical portion (27) and is fitted onto the inner ring member (4a) and has an radially outer circular ring portion (28) extending radially outwards. The seal (19) has a generally annular reinforcing metal member (21) with a J-shaped cross section provided on the stationary outer ring member (5a). The reinforcing member (21) has an outer peripheral edge portion formed with a radially outer cylindrical portion (23) fitted into the outer ring member (5a), and a radially inner circular ring portion (24) extending radially inwards at a position axially outwards of the rotatable circular ring portion of the slinger (26). The stationary circular ring portion (24) has a seal member (22) fixed generally along the periphery thereof, and has seal lips (25a, 25b, 25c) with tip ends placed in sliding contact with the slinger (26). At least one seal lip (25a) has its tip end in sliding contact with an inside face of the rotatable circular ring portion (28). The tone wheel (29) has an outer peripheral edge portion (31) formed with an engagement portion thereon and provided adjacent to an outside face of the rotatable circular ring portion with the engagement portion engaged with the outer peripheral edge of the rotatable circular ring portion (28).