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Rigid locking in pull direction, push-in direction relatively rigid
Here the locking function takes place in an oil chamber which is separated from the gas using a floating piston. If a force is applied on the locked spring in extension direction, because there is only oil between the piston and the guide piece, the locking force remains rigid up to the mechanical strength of the spring. If a force is applied in the compression direction, the spring remains rigid until the force of the pressure on the floating piston is exceeded (locking force).