Inventors:
Stephen Sekulich - Foster City MI, US
Richard Paulson - Fenton MI, US
Gregory Watson - Durand MI, US
International Classification:
F16J015/46
Abstract:
An improved, polytetrafluoroethylene shaft sealing element, and a method to make the sealing element: The improved element is characterized by being manufactured as one piece of a selected polytetrafluoroethylene mixture (which is conventionally clamped in a conventional housing) that has a strategically placed circumferential groove and that preferably has hydrodynamic grooves that end at a selected distance from the toe end of the seal. Optionally, the improved seal may include a wiper lip as part of the one piece of a polytetrafluoroethylene mixture. Alternatively, the improved element may have the thickness of the part of the seal bearing on the shaft tapered in its thickness (not of uniform thickness). Adjustment of these properties optimizes the pressure distribution of the part of the seal that bears on the shaft with a resultant significant increase in the effective lifetime of the seal and significant improvement in the effectiveness of the seal.