| 摘要 |
<p>A lifting means for a vertically-movable gate or door (1) comprises a cable (3) attachable to a respective end of two ends of the gate or door. The cable passes over pulleys (4) and round a sheave (5) which is provided with displacement means (8) to move it up and down, thereby lowering and raising the gate. The sheave can be driven clockwise and anticlockwise to correct any inequality in level between the ends of the gate or door. <IMAGE></p> |
