| 摘要 |
<p>Equipment for remotely operating by transmitted signals self-advancing supports which are used with a shearer at a long-walled pit face in a coal mine comprises electromagnetic valves, one of which is connected to a hydraulic cylinder for lowering the roof plate of a self-advancing support and moving the support toward the pit face and the other of which is connected to another hydraulic cylinder for lifting the roof plate of the support, a signal converter and a receiver are connected through a cable to the electromagnetic valves including those of the other self-advancing supports in such a manner that each of the electromagnetic valves is specified through the matrix circuit system; and a portable transmitter is provided for transmitting operation signals to the receiver through the radio system.</p> |
