Patent ID: 7374344

Claim:
A wheel support bearing assembly comprising: an outer member adapted to be secured to a vehicle body structure and having an inner peripheral surface formed with a plurality of raceways defined therein; an inner member adapted to support a vehicle wheel and having raceways defined therein in alignment with the respective raceways in the outer member; corresponding circular rows of rolling elements each row interposed between the raceway in the outer member and the raceway in the inner member; a sensor cap secured to an inboard end of the outer member to close an inboard opening of the outer member; an insert nut embedded in a portion of the sensor cap, which is made of a synthetic resin, with its one open end opening at outer surface of the sensor cap, a sensor insertion hole being defined in the sensor cap in a juxtaposed relation with the insert nut; a sensor support member carrying a sensor arranged on an outer surface of the sensor cap with the sensor inserted into the sensor insertion hole and having a bolt insertion hole defined therein; a sensor fastening bolt inserted into the bolt insertion hole and then threaded into the insert nut to fix the sensor support member to the sensor cap; and a pulsar ring provided on the inner member so as to confront the sensor and cooperable with the sensor; wherein the sensor cap has a reduced diameter hole defined therein at a location adjacent a deep end face of the insert nut so as to communicate between an internally threaded bore of the insert nut and the inside of the sensor cap, which reduced diameter hole has an inner peripheral surface formed with a counter surface confronting the deep end face of the insert nut; and wherein a sealing member having an elasticity is interposed between the counter surface of the reduced diameter hole and the deep end face of the insert nut under interference fit therebetween for thereby sealing.