BEARING CAP

PROBLEM TO BE SOLVED: To provide a bearing cap having a superior installing stability against an outer ring and tight-sealing characteristic and capable of making an air gap between an annular magnet and a magnetic sensor as less as possible.SOLUTION: This invention relates to a bearing cap 10 installed at an inner diameter part 21 of an axial opening part 20 of an outer ring at a hub bearing device 1 comprising an inner ring having an annular magnet 9 integrally installed to it, and an outer ring 2 for supporting the inner ring in such a way that it may be axially rotated so as to seal the opening part 20 under a state in which it is positioned between a magnetic sensor 30 and the annular magnet 9, the outer ring is provided with a peripheral groove 22 at its inner diameter part, there are provided a cap main body 11 and an annular seal part 12 of a resilient body fixed to an outer peripheral edge 11a of the cap main body, a radially inner portion at the outer peripheral edge part is applied as an acted part 11b of a press-in jig 40. When the press-in jig is acted on the acted part to install the bearing cap, the outer peripheral edge part 11a of the cap main body is expanded at its diameter part together with the annular seal part and it is fitted into and installed in the peripheral groove 22. 【課題】外輪に対する装着安定性及び密封性に優れ、しかも、環状磁石と磁気センサとの間のエアギャップを極力小さくすることができる軸受用キャップの提供。【解決手段】環状磁石９を一体に備える内輪と、該内輪を軸回転自在に支持する外輪２とを備えるハブベアリング軸受装置１における前記外輪の軸方向開口部２０の内径部２１に装着されて、磁気センサ３０と環状磁石９との間に位置する状態で前記開口部２０を封止する軸受用キャップ１０であって、前記外輪は内径部に周溝２２を備え、キャップ本体１１と、キャップ本体の外周縁部１１ａに固着された弾性体の環状シール部１２とを備え、前記外周縁部の径方向内側部分は圧入治具４０の被作用部１１ｂとされ、該被作用部に圧入治具を作用させて軸受用キャップを装着させる際、キャップ本体の外周縁部１１ａは環状シール部と共に拡径して周溝２２内に嵌入装着されるよう構成されていることを特徴とする。【選択図】図３