US Patent 7963526 Prelubricated multi-lipped radial shaft seal with large radial offset accommodation

A radial shaft seal is provided for accommodating large radial offset of the shaft relative to a housing. The seal includes an annular retainer insert provided for engaging the seal to a fixed housing. An annular elastomeric seal body is molded to the retainer insert and includes a flexible axially extending portion extending from an inner surface of the retainer insert. A seal portion extends from a radially inward end of the flexible portion and includes first and second seal lips and an elastomeric bearing surface disposed between the first and second sealing lips. The bearing surface includes a plurality of raised pads adapted to engage the shaft. The pads each include a rounded edge on lateral sides thereof for encouraging the creation of a lubricating film between the pads and shaft. The pads are lubricated by a lubricant disposed in a lubricant chamber disposed between the first and second seal lips.