Patent ID: 7600617

Claim:
An industrial shock absorber for use in a telescopic tow bar assembly, the shock absorber comprising: a housing having opposed ends and having a longitudinal axis defined between said ends; a first end cap adjacent one of said ends; a second end cap adjacent the end opposite said first end cap and having an opening therethrough; a piston rod received through said opening of said second end cap and having one end received in said housing and another end extending outwardly from said housing; a piston attached to said one end of said piston rod for movement with said piston rod between retracted and extended positions, the piston having a first head and a second head that are connected together to define at least in part a chamber therebetween; a plurality of rollers carried at least in part in said chamber and exposed at least partially from the piston for rolling engagement with said housing; and at least one spring that yieldably biases the piston rod and the first end cap to a first position wherein the piston rod includes a chamber and the piston includes a central opening and said at least one spring extends through said opening and in said chamber of the piston rod.