摘要 |
A spring system for relatively displacing elements attached to end mounts of the rod assembly comprises a housing having a rod member movable between extended and retracted positions relative thereto, and a first spring in the housing surrounded by a second spring for biasing the rod member to one of an extended or retracted position relative to the housing. The two springs exert a non-linear load versus deflection curve as the rod member moves between an extended position and a retracted position. |