| 摘要 |
<p>The mechanism is mounted on a plate (12) fixed to the door panel (1), and has a pulley (13) driven by a motor-reduction gear unit (14) to displace a cable (15). The cable is attached (16) to the door frame upright (4), and to an arm (18) pivotted from a bracket at the top of the frame. A return spring (21) attached to the arm maintains cable tension. In an alternative form the cable may be replaced by a chain operating in conjunction with toothed sprocket wheels.</p> |
