Patent ID: 6109793
Filing Date: 2000-08-29
Classification: F16C,G01P

Abstract:
A rolling bearing unit with a rotational speed sensor comprising:a stationary outer ring having an inner peripheral surface formed with outer ring raceways in double rows, and a mount hole in an axially intermediate portion thereof,a rotatable inner ring assembly comprising a first inner ring having an outer peripheral surface formed with a first inner ring raceway and a second inner ring having an outer peripheral surface formed with a second inner ring raceway,a plurality of rolling members provided between the first and second inner ring raceways and the outer ring raceways to define a set bore diameter, respectively,an encoder having a detected portion having characteristics changing alternately with a uniform interval in a circumferential direction and fixed concentrically with the inner ring assembly at a portion on the inner ring assembly axially between the first and second inner ring raceways, the detected portion having an outer peripheral surface portion, anda sensor for producing an output signal, having a detecting portion and supported within the mount hole with the detecting portion opposed to the outer peripheral surface portion of the detected portion of the encoder,wherein the output signal of the sensor changes as the characteristics of the detected portion alternately change, andwherein the encoder has an outer diameter which is smaller than the set bore diameter defined by the rolling members in the row through which the encoder passes during assembly.