METHOD FOR AUTOMATIC SPEED CONTROL OVER FEED OF COAL MINERS AND DEVICE FOR IMPLEMENTING THE SAME Russian patent published in 1996 - IPC

FIELD: mining. SUBSTANCE: load current and cutoff current as a function of voltage are set on terminals of electric motor of miner cutting drive. Mean consumption current I_m, mean square current deviation σ_I and probable value of maximum current I_max are determined in the presented mathematical expression. I_m and I_max are compared with preset values and keep them at the level that is not higher than set points by adjusting speed of the coal miner. Device for implementing the method contains two adjusting channels. One channel has current sensor and aperiodic link connected in series. The second channel contains current sensor, adder, quadrator, aperiodic link, square root evaluator, the first proportional link, and the second proportional link with adjustable dead zone connected in series. Inputs of the two channels are connected to control system by miner feed mechanism. EFFECT: high capacity. 2 cl, 2 dwg