| 摘要 |
<p>The installation comprises a switch 121 interposed between an electrical source 117 and the motor 105 of a capstan 104, which switch is of the type with two parts, one 121a of which is integral with moving equipment 108 and the other 121b of which is integral with a car 103. The electrical elements of the installation such as the motor 105, electromagnets 118 and 119 and a motor 114 of a drum 110 for joining cables 116 are supplied directly by a line 200 from the electrical source 117 whilst a line 300 reaches as far as the part 121b of the switch 121, and the other part 121b receives the lines corresponding to the supply to the other poles of the aforesaid electrical elements 105, 118, 119, 114. When the current is interrupted, the electromagnets 118- 119 are de-energized and springs 149-150 push the levers 141-142. The car 103, thus detached from the movable equipment 108, descends under its own weight, unrolling the joining cables 116. A centrifugal brake 112 guarantees a reasonable and constant speed until the car 103 reaches stopping buffers. Even if the current is re-established while the car is descending under its own weight, the motor 105 is unable to start up because the switch 121 is open.</p> |
