Patent ID: 7618194

Claim:
A wheel bearing apparatus incorporating a wheel speed detecting apparatus comprising an outer member having an integrally formed body mount flange and double row outer raceway surfaces formed on the inner circumferential surface of the outer member; an inner member including a wheel hub having an integrally formed wheel mounting flange at one end and a cylindrical portion axially extending from the wheel mounting flange and an inner ring fitted on the cylindrical portion of the wheel hub, double row inner raceway surfaces being formed on the outer circumferential surfaces of the wheel hub and inner ring, respectively, opposite to the double row outer raceway surfaces; double row rolling elements rotatably arranged between the outer and inner raceway surfaces; an encoder mounted on the outer circumferential surface of the inner ring; an annular sensor holder arranged on the end of the outer member opposite to the encoder; a sensor of wheel rotation speed integrally molded with the sensor holder and arranged opposite to the encoder via a predetermined axial gap; the encoder has an annular plate configuration and its characteristics alternately and equidistantly vary along its circumferential direction; a seal is arranged at the inboard side of the encoder via the sensor holder, the seal including first and second annular sealing plates, said first annular sealing plate fitted on the sensor holder and said second annular sealing plate fitted on the inner ring, respectively, and opposite toward each other and a sealing member sealing between said first and second annular plates; and an inboard end surface of the outer member is further outboard than an inboard end surface of the inner ring.