Bearing assembly with rotation sensor
An annular sensor holder ( 5 ) has an axial end ( 15 ) including a protrusion ( 18 ). The axial end ( 15 ) is fitted in a circumferential groove ( 7 ), such as a seal groove, of a bearing race ( 2 ) fitted to a stationary member ( 9 ) so that the sensor holder ( 5 ) can slide in the circumferential direction relative to the bearing race ( 2 ). In this state, the sensor holder ( 5 ) is coupled to the stationary member ( 9 ) by a fixing arrangement ( 19 ). Thus, when the bearing race ( 2 ) creeps, the sensor holder ( 5 ) slides relative to the bearing race ( 2 ) and does not rotate relative to the stationary member ( 9 ). This prevents breakage of connecting wires.
1. A bearing assembly with a rotation sensor, comprising:
a rolling bearing including an inner race and an outer race, an annular sensor holder, and a magnetic sensor supported by the sensor holder,
wherein the sensor holder can be fitted to one of the inner and outer races,
wherein with the rolling bearing mounted between a stationary member and a rotary member, the sensor holder mounted to the one of the inner and outer races, and a signal from the magnetic sensor entered into an external device through wires extending from the sensor holder to the external device, detection is made by the magnetic sensor and an encoder rotationally fixed to the other of the inner and outer races so as to rotate in unison with the other of the inner and outer races,
wherein the sensor holder is mounted to the one of the inner and outer races so as to be in contact with and slideable relative to the one of the inner and outer races in a circumferential direction of the rolling bearing,
wherein the one of the inner and outer races is fitted to the stationary member,
wherein the bearing assembly further comprises a fixing arrangement through which the sensor holder is coupled to the stationary member such that when fitting surfaces of the stationary member and the one of the inner and outer races rotate relative to each other, the sensor holder is circumferentially fixed with respect to the stationary member but slides in the circumferential direction relative to the one of the inner and outer races in the event of creep between the stationary member and the one of the inner and outer races,
wherein the one of the inner and outer races is formed with a circumferential groove extending along an entire circumference of the one of the inner and outer races,
wherein the sensor holder has two circumferential ends circumferentially facing each other, and
wherein the sensor holder has a protrusion at a first axial end of the sensor holder, the protrusion being engageable in the circumferential groove by elastically deforming the sensor holder such that the size of a gap defined between the circumferential ends of the sensor holder changes in the circumferential direction.
2. The bearing assembly of claim 1 , wherein the sensor holder can be coupled to the stationary member by the fixing arrangement at two portions of the sensor holder which are nearer to the respective circumferential ends of the sensor holder such that when the sensor holder is coupled to the stationary member at the two portions, a circumferential distance between the circumferential ends of the sensor holder is fixed.
3. The bearing assembly of claim 1 , wherein the one of the inner and outer races has a first peripheral surface formed with a raceway, and the circumferential groove is one of two seal grooves formed on the first peripheral surface of the one of the inner and outer races.
4. The bearing assembly of claim 1 , wherein the sensor holder includes a coupling portion, and wherein the fixing arrangement comprises at least one threaded member fastening the coupling portion to the stationary member in an axial direction of the rolling bearing.
5. The bearing assembly of claim 4 , wherein the coupling portion protrudes from the sensor holder in a direction away from the one of the inner and outer races.
6. The bearing assembly of claim 4 , wherein the coupling portion extends so as to axially overlap a side surface of the stationary member.
7. The bearing assembly of claim 1 , wherein the fixing arrangement includes an engaging member extending diametrically between the stationary member and the sensor holder, wherein the sensor holder can be coupled to the stationary member through the engaging member, and
wherein the engaging member includes a peripheral portion supporting a second axial end of the sensor holder protruding from the one of the inner and outer races in a radial direction of the rolling bearing, and a side portion supporting the second axial end of the sensor holder in an axial direction of the rolling bearing.
8. The bearing assembly of claim 7 , wherein the sensor holder has first protrusions and recesses formed at the second axial end of the sensor holder, and wherein the engaging member has second protrusions and recesses which engage the first protrusions and recesses in the circumferential direction.
9. The bearing assembly of claim 1 , wherein the fixing arrangement fixes the sensor holder to the stationary member.
10. The bearing assembly of claim 1 , wherein the fixing arrangement fixes the sensor holder to the stationary member so that the sensor holder is both axially and circumferentially fixed to the stationary member.