Patent ID: 8087831
Filing Date: 2012-01-03
Classification: B60T,G01D,G01P

Abstract:
1. A wheel-rotation support apparatus with encoder comprising: a stationary race which does not rotate when supported by the suspension, a rotating race which is located concentric with the stationary race to rotate together with a wheel, a flange which is formed around the outer peripheral surface of the rotating race to support the wheel and a rotating brake member, a plurality of rolling elements which are located between the stationary-raceways and rotating-raceways that are formed around the opposing peripheral surfaces of the stationary race and rotating race such that they can roll freely, a seal member which is provided to separate the external space from the space inside the bearing where the rolling elements are located, a permanent magnet encoder which is located on the side closer to the external space of the seal member and supported by a section that rotates together with the rotating race, S-poles and N-poles of the permanent magnet encoder being arranged on a detected surface to alternate in a circumferential direction, and a labyrinth seal which is located between the encoder and the external space, wherein a width of the clearance of the labyrinth seal is 40% of the pitch of adjacent S-poles and N-poles that are arranged on the detected surface of the encoder, and the labyrinth seal is formed by a portion of a constant velocity joint connected and fixed to the rotating race and a portion of the knuckle of the suspension wherein the portions come closer to each other, such that magnetic powder having particles with a diameter greater than 40% of the pitch of adjacent S-poles and N-poles cannot attach to the detected surface of the encoder so as to improve the reliability in detecting a wheel rotation speed.