我矿过去采用的提升机过卷讯号装置是很重的行程开关。由于井筒中潮湿,节点易于锈蚀,线路时有不通,而机械部分也有卡死现象,不能带动节点断开。所以生产中使用这类过卷讯号不甚可靠。仅在1972年上半年,我矿副井曾先后发生四次过卷,幸好都未出现人身事故,但每次都把开关打坏。另 The mine hoist over-roll signaling device used in mine was a heavy travel switch. As the wellbore in the wet, easy to rust node, the line has nowhere, while the mechanical part of the stuck phenomenon, can not drive the node off. So in the production of such over-volume signal is not reliable. In the first half of 1972 alone, mine auxiliary shaft had occurred four times in succession, fortunately no personal accident occurred, but each time the switch broke. another