我矿自行设计的安全火花信号从1977年开始在采煤工作面、提升坡口、运输巷道等方面使用,至今效果良好,现简介如下:一、设计原则1、此装置适于采煤工作面放顶回柱及运输巷道信号联络之用。在正常情况下和故障情况下所产生的电火花均不能使周 Mine safety spark signal designed by mine from 1977 onwards in the coal mining face, to improve the bevel, transport tunnels and so on, so far, the effect is good, are as follows: First, the design principles of 1, the device is suitable for coal mining face Top back column and transport lane signal contact purposes. Under normal circumstances and under the circumstances of the fault generated spark can not make week