Endless track pin assembly

Claim 1

An endless track including a plurality of articulately connected track shoes, each of said track shoes connected to an adjacent track shoe by pairs of track pin assemblies, each of said track shoes comprising a yoke including a pair of spaced apart collars located at opposite lateral edges along one longitudinal extremity of said yoke, said collars having aligned bores equal in diameter, a single collar having a bore and located at opposite lateral edges along the other longitudinal extremity of said yoke, and a guide portion for guiding the track, each single collar of each shoe being located between a pair of spaced apart collars on the adjacent shoe, each single collar bore being coaxial with said equal diameter bores, each of said track pin assemblies including a pin rigidly connected with each of said pairs of collars, the pin having at one end a head adapted to fit in the equal diameter bores and at its other end a nut that is too large to fit in the equal diameter bores, and a plurality of bushings and washers on the pin between the head and the nut, said bushings and washers adapted in the relaxed state to fit in the equal diameter bores and radially expansible to grip the surfaces of the bores, a spherical bearing operatively positioned between each track pin and the single collar positioned between each of said pair of collars, said bearing including an inner race having a bore aligned with and substantially the same size as said equal diameter bores and rigidly secured about said track pin by said bushings and washers in their expanded state and having a spherically shaped outer bearing surface, an outer race concentric with said inner race, being rigidly connected with said single collar, and having a spherically shaped inner bearing surface complementary with said convex bearing surface, and a seal mounted on either side of said spherical bearing comprising first and second concentric rings and an elastomeric ring bonded to said first and second rings.