| 摘要 |
<p>A rope-descent device for lowering objects and in particular persons by means of a rope and comprising frame-mounted rollers around which a rope is run in a looped path, the friction resulting from rope-to-roller and rope to rope contact being such that the rope tension transmitted through the device is greatly reduced so that, when the device is supported from one end of the rope an object such as a person supported from the device may be lowered by feeding the other end of the rope, which is subject only to the reduced rope tension, through the device. Reversal of the roles of the rope ends, enables the device to be re-used without re-reeling the rope.</p> |
