Track assembly hinge joint

Claim 1

A hinge joint for connecting track elements of an endless track vehicle which comprises a bushing secured at its ends to the spaced ends of a pair of link plates and a pin received in the bushing and secured at its ends to the ends of a pair of adjoining link plates which are disposed outboard of the bushing carrying link plates, an axial movement limiting ring member secured on said pin adjacent each end of the bushing, a sleeve member secured on the pin and disposed between the bushing and the pin which sleeve member is formed of self-lubricating material, a washer formed of self-lubricating material secured on the pin at each end of the bushing which is disposed adjacent the end face of the bushing and the end face of said axial movement limiting ring member and a seal assembly mounted on said ring member at each end of the bushing, said seal assembly comprises an inner seal element which has a face engaging the end face of said bushing, a base portion which is seated on said movement limiting ring member, and an annular sealing lip extending in an outward axial direction and an outer seal element having an annular sealing lip which extends in an axial direction and is in resilient engagement with an outer radial face of said base portion of said inner sealing element, said outer seal element further having an outer base portion, said annular sealing lip of said inner seal element being in resilient engagement with an inner radial face of said outer base portion, and said base portion of said inner seal element is disposed between an outer radial face of said movement limiting ring member and the radially inner most portion of said outer seal element.