BEARING DEVICE ADAPTED FOR USE IN WHEEL AND EQUIPPED WITH ROTATION SENSING DEVICE

摘要

A bearing device adapted for use in a wheel and equipped with a rotation sensing device is compact in size and enables accurate sensing of rotation by preventing wear, swelling, and positional displacement of a magnetic encoder.  A bearing device for a wheel, having rolling bodies (5) mounted between a rolling surface (3) on the inner periphery of an outer member (1) and a rolling surface (4) on the outer periphery of an inner member (2), wherein a magnetic encoder (21) is mounted to the outer peripheral surface of the inner member (2).  A sensor holder (25) incorporating a magnetic sensor (24) is mounted to the outer member (1), and the magnetic sensor (24) faces axially the magnetic encoder (21) with a predetermined gap therebetween.  A gap between the sensor holder (25) and the inner member (2) is sealed by a sealing device (8).  The magnetic encoder (21) is a plastic magnetic encoder.  On either or both of the magnetic encoder (21) and the inner member (2) are formed engaging sections (21ab, 10a) for engaging the magnetic encoder (21) and the inner member (2) with each other to axially restrict the magnetic encoder (21) in position.