| 摘要 |
<p>A spring system for relatively displacing elements attached to end mounts of the rod assembly comprises a housing having a rod member (30) movable between extended and retracted positions relative thereto, and a first compression spring (120) in the housing surrounded by a second compression spring (122) for biasing the rod member to one of an extended or retracted position relative to the housing, the two springs are oppositely wound whereby, from a compressed condition, the spring rod exerts an expansion force which increases at a linear rate. The spring system includes a valve arrangement (138, 140) to control the rate at which the spring rod moves from a retracted position to an extended position.</p> |
