| 摘要 |
<p>The device has a hand grip and an apron opposite to it. It has a ring corresponding to the side of the shaft, which rests on the ground and projects partially into the shaft. It has two vertical steps, to which accessories may be connected. A crossbar between the steps is used as a hand grip. A seal formed by e.g. an air-filled hose, is located between ring and shaft wall and prevents entry of water. The apron is located opposite to the hand grip, and protects the back of the operator. The accessories may be e.g. a ladder, a crane jib with pulley and cable, for safety or recovery operations after accidents. Any person recovered from the shaft can be placed directly on a stretcher.</p> |
