Patent ID: 7909718
Filing Date: 2011-03-22
Classification: F16G

Abstract:
1. A seal chain comprising: an inner link plate having an opening therein; an outer link plate disposed with a clearance between said inner link plate and said outer link plate, said outer link plate being movable in a direction toward said inner link plate; a bush having a bush head portion projecting through said opening in said inner link plate into said clearance; and a sealing member, ring-shaped and disposed surrounding said bush head portion between said inner link plate and said outer link plate, said sealing member having a substantially plus-shaped cross-section, said sealing member including: wherein said third lip portion and said fourth lip portion are mirror-symmetrical with respect to each other, wherein said outer side face of said third lip portion is a uniformly tapered face having a predetermined gradient, or said outer side face of said third lip portion is a tapered face having a circular arc and a radius of curvature of said circular arc is greater than a radius of curvature of a curve connecting said third lip portion to said first lip portion, wherein a ratio of a diagonal distance across said center base portion of said sealing member to a distance of said clearance is in a range of 0.8 to 1.0, and wherein said seal member is disposed with said first lip portion between an edge of said bush head portion and said outer link plate, as to be rotatable and deformable into a shape having a substantially X-shaped cross-section by a movement of said outer link plate in a direction toward said inner link plate.