| 摘要 |
<p>The rope lowering device is particularly for escaping from a building on fire. It comprises a tube formed into a retarder spiral with one or more turns (1) and through which the rope (7) runs. As the rope moves through the tube, friction is generated restricting its travel speed. The tube can be of metal or other wear-resistant and non-inflammable material, and the rope can be steel, and of roughly 5 mm. diameter. The turns of the sprial can be tack-welded together.</p> |
