| 摘要 |
<p>The barrier (1) has a contention walking beam (7) including a return unit provided with an extension spring (14) made of elastomer material. An inner end of the spring is fixed on the beam, while an outer end of the spring is fixed to a vertical chassis (2). The spring is arranged in a manner to be deformed along a stretched configuration when the beam is displaced into a closed position for exerting traction force on the beam assuring its automatic return to an open position according to deactivation of a locking unit (11).</p> |
