Gas spring

摘要

A gas spring with a piston reciprocable in a chamber of a casing, a sealing assembly at the rear end of the casing through which the piston rod extends, and an end cap closing the rear end of the casing. The sealing assembly has a reinforcing ring having a sealing ring on one side and a wiper on the other side. The sealing ring and wiper are portions of a single body of elastomeric material molded to the reinforcing ring and integrally connected through one or more openings in the reinforcing ring. The casing wall is rolled radially inwardly over the sealing assembly into pressure contact with the reinforcing ring so that the sealing assembly becomes in effect an end cap for the front end of the casing. The rear end of the casing is rolled over the rear end cap by swaging into pressure contact with the end cap. A filler valve is disposed in the end cap. In use, the piston is normally retained on the rod by an enlargement having a diameter larger than the bore of the rod bearing so that in the unlikely event the piston separates from the rod the enlargement will be embedded in the bearing to retain the rod in the casing. If the piston separates from the rod a port in the rod vents to the atmosphere the compressed gas in the chamber.