Washer with elastic water-swellable rubber

Abstract

A washer system comprising: an annular washer having a central opening and an annular packing member which is coaxially arranged with the annular washer, at least a portion of the annular packing member being arranged within the central opening of the annular washer; at least a portion of the outer surface of the annular washer being rust-proofed treated. A substantial portion of a contacting surface between the annular washer and the annular packing member is not rust-proofed treated. The annular packing member is made of an elastic water-swellable rubber. The annular packing member has a portion which extends radially outwardly from a portion of the annular washer defining the central opening, and contacts a portion of a lower substantially flat surface of the annular washer radially outwardly of the annular opening. The annular packing member has a portion extending below a lower substantially flat surface of the annular washer. The annular washer and the annular packing member are adhered together by a vulcanized adhesive.

Dependencies are inferred from the claim text.