| 摘要 |
<p>The drive mechanism is for a large sliding door, esp. of the fire-protective type, with electric motor for opening, linked to the door by a coupling and a transmission system. For automatic closure there is a weighted traction cable. The transmission mechanism is connected to a brake, and is pref. in the form of a traction cable, with drum linked to brake, via chain drive. The brake may be of the fluid type, and the coupling magnetic. This obviates danger of door accelerating on closure to trap any person or object in its path.</p> |
