Patent ID: 6622831
Filing Date: 2003-09-23
Classification: C08F,C08L,F16F

Abstract:
A gas spring, comprising:a first tube having an inner wall; a head plate connected to the top of said first tube and having an opening; a base plate connected to the bottom of said first tube; a piston/rod assembly having a piston rod extending through the opening in said head plate and having a piston with a top and bottom, said piston/rod assembly being mounted to reciprocate in said first tube between a retracted, compressed position and an extended, rest position; wherein said first tube, piston, head plate and base plate define, at least in part, a primary gas chamber; wherein said first tube, piston, piston rod and head plate define, at least in part, a relief chamber; wherein said piston/rod assembly defines a passageway providing communication between the primary gas chamber and relief chamber, the passageway having a first opening to the primary gas chamber and having a second opening to the relief chamber; a valve member separate from said piston/rod assembly and mounted with said piston/rod assembly to move between an open position uncovering one of the first and second openings and a closed position closing off said one of the first and second openings and preventing fluid flow between the primary gas chamber and the relief chamber; seals for preventing fluid flow from the primary and relief chambers; and, at least one braking member held by said valve member and positioned between said valve member and said first tube to exert a force between said valve member and said first tube contrary to any force acting to move said valve member relative to said first tube.