Patent ID: 6209879
Filing Date: 2001-04-03
Classification: F16J

Abstract:
A sealing apparatus, which is applied to a rotary member, said sealing apparatus comprising:a metal ring having a cylindrical portion and an inward flange portion extending radially inward from an open-air side end of the cylindrical portion;a first sealing member made of an elastic rubber material, said first sealing member having a cylindrical portion in which the cylindrical portion of said metal ring is buried, and a radial portion opposite to the inward flange portion of the metal ring, and a first sealing lip axially extending from the radial portion to a sealing liquid side and having a lip leading end tightly, slidably contacting a surface of the rotary member;a second sealing member made of a resin material, and having a flange-shaped interposed portion held between the inward flange portion of the metal ring and the radial portion of the first sealing member and a second sealing lip extending from an inner-diameter end portion of the flange-shaped interposed portion towards the axial sealing liquid side and being positioned in a gap defined between the open-air side of the first sealing lip and the rotary member so that an inner peripheral portion of the second sealing member tightly, slidably contacts the surface of the rotary member;a first screw pump means provided on a sliding surface of the first sealing lip and adapted to provide a pumping function for transporting a liquid between sliding surfaces under an effect of a rotational sliding motion to the rotary member; anda spiral or ring-shaped second screw slot formed on the sliding surface of the second sealing lip extending from the sliding surface thereof to a bent portion continuous to the interposed portion.