Patent ID: 9097376
Filing Date: 2015-08-04
Classification: B29C,F01N,F16J,F16L

Abstract:
1. A spherical annular seal member for use in an exhaust pipe joint comprising: a spherical annular base member defined by a cylindrical inner surface, a partially convex spherical surface, and large- and small-diameter side annular end faces of the partially convex spherical surface; a plurality of partially convex spherical intermediate layers which are formed integrally on the partially convex spherical surface of said spherical annular base member and are laminated in a radial direction; and an outer layer formed integrally on a partially convex spherical surface of an outermost one of said plurality of partially convex spherical intermediate layers, wherein said spherical annular base member includes a first reinforcing member for said spherical annular base member made from a compressed knitted metal wire net which is knitted by using a fine metal wire with a diameter of 0.28 to 0.32 mm and whose mesh size is 4 to 6 mm long and 3 to 5 mm wide and a heat-resistant material for said spherical annular base member containing expanded graphite and compressed in such a manner as to fill meshes of the knitted metal wire net of the first reinforcing member and to be formed integrally with the first reinforcing member in mixed form, wherein each of said partially convex spherical intermediate layers includes a second reinforcing member for said partially convex spherical intermediate layer made from the compressed knitted metal wire net which is knitted by using a fine metal wire with a diameter of 0.10 to 0.20 mm and whose mesh size is 1.0 to 3.0 mm long and 0.5 to 2.5 mm wide and a heat-resistant material for said partially convex spherical intermediate layer containing expanded graphite and compressed in such a manner as to fill meshes of the knitted metal wire net of the second reinforcing member for said partially convex spherical intermediate layer and to be formed integrally with the second reinforcing member in mixed form, an occupying area ratio of a surface constituted by the second reinforcing member for said partially convex spherical intermediate layer on an outer surface of each of said partially convex spherical intermediate layers being 30 to 60%, and wherein said outer layer includes a third reinforcing member for said outer layer made from a compressed knitted metal wire net which is knitted by using a fine metal wire with a diameter of 0.10 to 0.20 mm and whose mesh size is 1.0 to 3.0 mm long and 0.5 to 2.5 mm wide, a solid lubricant consisting of a lubricating composition, and a heat-resistant material for said outer layer containing expanded graphite, the heat-resistant material for said outer layer and the solid lubricant being compressed in such a manner as to fill meshes of the knitted metal wire net of the reinforcing member for said outer layer, an outer surface of said outer layer being formed into a smooth composite surface in which a surface constituted by the third reinforcing member for said outer layer and a surface constituted by the solid lubricant are exposed in mixed form, an occupying area ratio of the surface constituted by the third reinforcing member for said outer layer on the outer surface of said outer layer being 30 to 60%.