| 摘要 |
PURPOSE:To enable plural number of cages operating in one common shaft to run always maintaining a safe distance between themselves which ensures prevention of any collision. CONSTITUTION:Travel speed of each cage is periodically detected by a speed detecting means. The minimum allowable distance from a cage to the foregoing one which can prevent collision at the time of sudden stop of the foregoing cage is calculated by a minimum allowable distance computing means using the speeds of the two cages obtained by the speed detecting means. Furthermore, the distance between a cage and its foregoing cage is periodically detected by a distance detecting means. When an actual distance is found smaller than the minimum allowable distance while the actual distance between the two cages obtained by the distance detecting means is compared with the minimum allowable distance obtained by the minimum allowable distance computing means, the following cage compulsorily reduces its speed to avoid collision. |
