An oil lubricated rotating hub (14) and stationary spindle (12) assembly
includes an oil bath seal (16, 16') for establishing a dynamic sealing
interface between the hub (14) and spindle (12). A wheel sensor assembly
includes a variable reluctance senor (54) targeted at an encoder ring
(56, 56') which is integrated into the oil bath seal (16, 16'). The
encoder ring (56, 56') is of the permanent magnet type including a
plurality of magnetically polarized sectors alternating between North and
South polarities. The use of an encoder style target (56, 56') in
combination with a variable reluctance sensor (54) enables improved slow
speed sensing with relatively large air gap spacing between the exposed
(58, 58') of the encoder ring (56, 56') and the head of the VR sensor
(54). Furthermore, the encoder ring (56, 56') enables use of less
expensive, lighter materials for the oil bath seal carrier (20, 20').