US Patent 9534635 Wheel bearing apparatus

A wheel bearing apparatus has an outer member, an inner member, at least one inner ring fit onto the inner member. Double row rolling elements are rollably arranged between the outer and inner raceway surfaces, via cages. A seal is mounted on one end of the outer member. The seal has side lips adapted to be in sliding contact with the wheel hub. The seal has three inclined side lips each extending radially outward from the seal body. The lips are adapted to be in sliding contact with the base of the wheel mounting flange. Interference of the side lips against the base of the wheel mounting flange is set so that the radially inner side lip has a smaller interference than that of the radially outer side lips, in order.