ROTATING SPEED-DETECTING DEVICE FOR WHEEL BEARING

摘要

PROBLEM TO BE SOLVED: To provide a rotating speed detecting device which can always accurately detect the rotating speed of a wheel on the not driven side. SOLUTION: A pulser ring 9 is attached to the end section of the inner race 3 of a wheel bearing. An electromagnetic sensor 11 which is opposed to teeth 9a formed on the outer peripheral section of the side face of the ring 9 with an axial gap in between is supported with a cap 12 fitted to the end section of the outer race 2 of the wheel bearing. The variation of the gap between the ring 9 and sensor 11 by temperature changes is prevented by forming the cap 12 of a material having a coefficient of linear expansion which is equal or close to that of the ring 9 so as to suppress the drop of the output voltage of the sensor 11.