Patent ID: 7597410

Claim:
An endless track chain device, comprising: first and second links, and a track chain joint comprising: a bushing to which the first link is fixed, a pin received in the bushing and to which the second link is fixed such that the pin and the bushing are rotatable relative to one another for corresponding relative rotation between the first and second links, an annular spacer spacing the bushing and the second link axially apart from one another, and an annular radial seal unit that inhibits ingress of debris between an end face of the bushing and the second link into a region between the pin and the bushing, the radial seal unit spaced axially apart from the end face and acting radially inwardly sealingly against the spacer therearound and radially outwardly sealingly against the second link, the bushing comprises axially opposite first and second end portions, the end face is one of multiple axially-facing surfaces of the first end portion facing in the same axial direction, and the radial seal unit is spaced axially apart from all the axially-facing surfaces of the first end portion.