Patent ID: 6302403
Filing Date: 2001-10-16
Classification: F16C,F16J

Abstract:
A sealing assembly for two mechanical members connected for relative rotation, comprising:a substantially rigid shield adapted to be carried integrally by a first of said mechanical members;an annular sealing member projecting radially from said shield and comprising a first axial sealing lip and a second axial sealing lip, said first and second axial sealing lips both projecting axially from a first annular face of said annular sealing member that is adapted to substantially face a sealing surface provided on a second of said mechanical members, said first and second axial sealing lips being adapted to cooperate in a sliding manner with the sealing surface;said annular sealing member comprising a root portion projecting radially from said shield, an end portion projecting axially at a free radial end of said annular sealing member, and an intermediate portion extending radially between said root portion and said end portion, said intermediate portion being connected to said root portion by a narrow section defining one elastically deformable virtual hinge;said annular sealing member being substantially T-shaped, said end portion projecting axially on opposite sides of said free radial end of said annular sealing member and having an axial extension greater than the axial extension of said intermediate portion of said annular sealing member;said first axial sealing lip being defined by a rounded first axial end of said end portion of said annular sealing member, said second axial sealing lip projecting axially from said intermediate portion of said annular sealing member;said elastically deformable virtual hinge allowing said annular sealing member to selectively assume a first operating position when said first annular face of said annular sealing member is subjected to a pressure substantially equal to the pressure on a second annular face of said annular sealing element that is opposite said first annular face of said annular sealing member, and a second operating position when said first annular face is subjected to a pressure significantly lower than the pressure on said second annular face;wherein in the first operating position said first axial sealing lip is adapted to mate with the sealing surface with a given amount of axial interference while said second axial sealing lip is adapted to mate with the sealing surface with substantially no axial interference to permit fluid passage between said second axial sealing lip and said sealing surface, and in the second operating position said second axial sealing lip is adapted through deformation of said elastically deformable virtual hinge to cooperate in a sliding manner with a given amount of axial interference with the sealing surface.