Bearing assembly

A bearing assembly including:

• a bearing including a rotatable inner race having a mounting portion integral with a rotatable member and having an annular first groove for rolling members and an annular stepped portion axially juxtaposed on the outer peripheral surface thereof, an annular member fitted on the stepped portion of said inner race and having a second groove for rolling members formed in the inner peripheral surface thereof, the axial length of said annular member being shorter than that of said stepped portion, an outer race fixedly disposed outside and concentrically with said inner race and having third and fourth grooves for rolling members axially juxtaposed in the inner peripheral surface thereof in opposed relationship with said first and second grooves for rolling members and having a radial through-hole formed between said third and fourth grooves for rolling members, two rows of balls interposed between said first and third grooves for rolling members and between said second and fourth grooves for rolling members, respectively, and a pair of seals disposed on the axially opposite outer sides of said two rows of balls between said inner race or said annular member and said outer race for sealing said inner and outer races;
• a pulser gear of magnetic material disposed in an annular space formed between the end surface of the stepped portion of said inner race and the end surface of said annular member which is opposed thereto and having convex portions and concave portions alternately formed circumferentially on the outer peripheral surface thereof;
• and
• a sensor mounted in the through-hole of said outer race and having its tip end proximate and opposed to the convex and concave portions of said pulser gear, the number of rotations of said rotatable member being detected by said pulser gear and said sensor.

A bearing assembly including:

• a bearing including a rotatable inner race having a mounting portion integral with a rotatable member and having an annular first groove for rolling members and an annular stepped portion axially juxtaposed on the outer peripheral surface thereof, an annular member fitted on the stepped portion of said inner race and having an annular second groove for rolling members formed in the inner peripheral surface thereof, a fixedly disposed outer race fixedly disposed outside and concentrically with said inner race and having third and fourth annular grooves for rolling members axially juxtaposed on the inner peripheral surface thereof in opposed relationship with said first and second annular grooves for rolling members, and having a radially extending through-hole formed in the outer end portion of one of said both grooves for rolling members in the portion thereof which is opposed to the convex and concave portions of said annular member, two rows of balls interposed between said first and third grooves for rolling members and between said second and fourth grooves for rolling members, respectively, and a pair of seal members interposed between said inner race or said annular member and said outer race on the axially opposite sides of said two rows of balls for sealing the space between said inner and outer races;
• a pulser gear comprising concave portions and convex portions alternately formed circumferentially on the outer peripheral surface of said annular member axially outwardly of said second annular groove for rolling members;
• and
• a sensor mounted in the through-hole of said outer race and having its tip end proximate and opposed to the concave and convex portions of said pulser gear, the number of rotations of said rotatable member being detected by said pulser gear and said sensor.