Patent ID: 8365930

Claim:
A railcar draft gear spring assembly, comprising: an axial stack of springs units, with each spring unit including a spring formed from a non-circular preformed block of copolyester elastomer of a given thickness defined between a pair of generally parallel flat surfaces and having a series of spaced corners with sides extending between said corners, and wherein said preformed block of copolyester elastomer further includes a lobe formed at each corner for channeling the flow of elastomer and with recessed sides extending between any two lobes and such that when said preformed block of copolyester elastomer is compressed to an extent of at least about fifty percent of said given thickness said preformed block of copolyester elastomer transmutes into said spring which spring, when subsequently put into service, as such will not suffer significant permanent deformation although a particular force is applied thereto; and with each spring unit further including a non-circular metal plate arranged in operable combination with each of the generally parallel surfaces of said non-circular preformed block of copolyester elastomer, with each plate having an outer profile and a series of grippers extending in a common direction away from one surface of said plate, with said grippers being arranged in a predetermined pattern relative to each other and relative to said preform for initially positioning said non-circular preformed block of copolyester elastomer relative to said plate and for thereafter restricting the flow of elastomer relative to the outer profile of said plates.