Patent ID: 8906291

Claim:
A piston rod and cylinder seal device, comprising: a cylinder creating a piston chamber extending between opposed first and second cylinder heads; a first piston slidably disposed in the piston chamber, the first piston having a piston rod connected thereto; a piston rod spud extending from the piston rod, the piston rod spud having a blind bore and a second piston slidably received in the blind bore; and a contact member connected to the second cylinder head, the contact member having a central passage extending therethrough, a seal member disposed in the second piston acting to seal the central passage when contact takes place between the seal member and the contact member; wherein the second cylinder head includes a spud receiving bore having the contact member disposed therein, a pressure passage communicating with the spud receiving bore, and a bore supply/vent passage communicating with the central passage of the contact member, and wherein when the piston contacts the second cylinder head the piston rod spud is fully received in the spud receiving bore and pressurized air in the bore supply/vent passaqe communicating with the contact member is isolated by the seal member from the pressure passage communicating with the spud receiving bore.