Patent ID: 7201380
Filing Date: 2007-04-10
Classification: F16J,G01P

Abstract:
1. A dynamic seal for a rotary shaft comprising a one-piece sleeve for being constrained in rotation directly on the shaft, the sleeve having a first portion disposed parallel to the shaft and a second portion forming an annular collar extending either radially from or parallel to the first portion, and an annular lip of PTFE polymer having a low coefficient of friction to come into sliding rotary contact with a stationary casing surrounding said shaft so that said dynamic seal provides sealing between said shaft and said casing, wherein said dynamic seal further comprises an annular encoder element of magnetizable polymer, wherein the encoder element includes a first annular face and a second annular face, the first annular face bonded directly to the annular collar or to the annular collar and the first portion, the second annular face having an first surface and a second surface, wherein the first surface presents a circular track provided with polarized marks formed by sectors with alternating north and south polarization, and wherein the annular lip is bonded directly to the second surface, the first surface and the second surface being either parallel or perpendicular to one another.