| 主权项 |
1. A rolling bearing unit with a rotational speed detecting device, the rolling bearing unit comprising:
an outer ring which includes double rows of outer ring raceways on an inner circumferential surface thereof and is not rotatable when used; a hub which includes double rows of inner ring raceways on an outer circumferential surface thereof, is supported concentrically with the outer ring at an inner diameter side of the outer ring and is provided with a rotation-side flange for supporting a wheel at a portion of an outer circumferential surface which axially protrudes outward with respect to an axially outboard end of the outer ring; a plurality of rolling elements which are rollably provided for each row between the outer ring raceways and the inner ring raceways, respectively; an annular encoder which is configured by alternately changing magnetic characteristics on an axially inboard surface thereof and is supported to an axially inboard end of the hub concentrically with the hub; a cap which is mounted on an axially inboard end of the outer ring and closes an axially inboard end opening of the outer ring; a sensor unit which includes:
a sensor which is provided to face a detected surface of the encoder and configured to change an output signal in response to a change in characteristic of the detected surface of the encoder; anda sensor holder including a sensor holding part which holds the sensor and is supported by a portion of the cap axially facing the encoder, and a sensor mounting flange part which is provided at a base end of the sensor holding part and is coupled and fixed to an axially inboard surface of the cap, wherein the cap includes a cap body, a fitting insert, and a mounting nut, wherein the cap body is formed of a synthetic resin as a whole, has a bottomed cylindrical shape including a cap cylindrical part and a cap bottom part, and is formed with a through-hole in a portion of the cap bottom part which axially faces the encoder, wherein the fitting insert is formed of a non-magnetic material as a whole, has a bottomed cylindrical shape including an insert cylindrical part and an insert bottom part, and is fixed to an inner diameter side of the cap cylindrical part in a state where the fitting insert is open axially outward and an axially outboard end opening of the through-hole is closed by the insert bottom part, wherein the mounting nut is molded in the cap body in a state where the mounting nut is open to an axially inboard surface of the cap body and is used to screw a bolt inserted through a hole of the sensor mounting flange part in a state where the sensor holding part is inserted to the through-hole, and wherein the cap is mounted on an axially inboard end of the outer ring in a state where the insert cylindrical part of the fitting insert is fitted into and fixed to the axially inboard end of the outer ring. |
