Bearing seal for sensing angular velocity

摘要

A seal for an antifriction bearing having a fixed inner race and a rotating outer race includes inner and outer seal cases which are pressed over cylindrical mounting surfaces on the inner and outer races, respectively. To this end, the seal cases have extended axial walls which actually fit over the mounting surfaces in the bearing races and radial walls, connected to the extended axial walls. The radial walls of the two cases are spaced apart so that an annular chamber exists between the two radial walls. Each seal case has an elastomeric seal element supported by its radial wall remote from its extended axial wall and that seal element establishes a fluid barrier along the other seal case, so that the two seal elements isolate the chamber from the interior of the bearing and from the environment at the exterior of the bearing. The inner case carries a sensor having a head that is located in the annular chamber between the two axial walls. The radial wall of the outer case carries means for exciting the sensor such that it produces a pulsating signal when the outer case rotates relative to the inner case, and the frequency of the signal reflects the angular velocity.