Patent ID: 8708343
Filing Date: 2014-04-29
Classification: F16J

Abstract:
1. A seal device having a backup ring protruding towards a fluid storage chamber so as to enclose a rotating shaft, wherein at least said backup ring has a tapered shape, and a distal end of a seal lip supported by the backup ring is capable of coming into contact with the rotating shaft; said seal device characterized in that: said backup ring has a protruding part, a tapered part and a distal end part extending continuously from a fixed part thereof; a rounded surface having a curvature radius (R-1) is formed at least in a first boundary where a surface of said tapered part changes to a surface of said distal end; and a rounded surface having a curvature radius (R-3) is formed in a second boundary where a surface of said protruding part changes to a surface of said tapered part; and the surface of said tapered part is a convex surface having a substantially constant curvature radius (R-2) greater than the curvature radius (R-1) of said first boundary; and the curvature radius (R-2) of said tapered part is the same curvature radius as the curvature radius (R-3) of said second boundary.