Patent ID: 7021609

Claim:
A gas spring comprising: a cylinder body; a rod member internally slidably fitted in said cylinder body; a gas chamber formed inside said cylinder body and filled with compressed gas; a seal member for sealing between said cylinder body and said rod member at least one end of said gas chamber; a ring member for partitioning said gas chamber at an end portion of said gas chamber, said end portion being close to said seal member; an annular grease chamber being defined between said seal member and said ring member and filled with grease; said ring member being externally slidably fitted on said rod member, and an outer periphery of said ring member being fitted in an annular groove in an inner periphery of said cylinder body; said rod member being disposed in a state of penetrating said cylinder body; and said gas chamber having ends, each of said ends including a seal member, a ring chamber and a grease chamber.