Piston rod seal for adjustable pneumatic spring

USRE29497A · kind A · utility

Assignee

• Stabilus GmbH · DE

Inventor

• Herbert Freitag · Koblenz, DE

Key dates

• Filing date: Mar 22, 1976
• Grant date: Dec 20, 1977
• Expiry date: Mar 22, 1996

Classification

• Technology area (CPC —): General

Abstract

In a pneumatic spring of adjustable length, the piston rod is sealed to the cylinder by an annular sealing disc stressed in compression between the inner cylinder wall and a rigid, tubular projection on the radial end wall of the cylinder through which the piston rod extends outward of the cylinder cavity. The sealing disc is axially longer than the projection so that it extends inward of the cavity beyond the projection and carries an annular sealing lip engaging the piston rod only under the fluid pressure in the cylinder cavity, but practically fully relieved by the annular projection from the compressive stresses.