JPS5518360A - Apparatus for processing by electric discharge - Google Patents

Abstract

PURPOSE:To enhance the processing accuracy by starting the supply of processing pulses when the position of the electrodes at the time of stopping motion comes to coincide with the position at the time of starting motion thereof, in a mechanism wherein processing pulse is stopped at the moment when the motion of expanding the processing clearance of electrodes is stated. CONSTITUTION:In the operation of controlling the density of cutting powder to be used at the processing wherein, e.g. electrodes 1 perform reciprocating motion using water etc., as processing aid, number of discharge occurrence etc., is judged at the judging circuit 7, the outputted signal is counted at the preset counter 8, and its output makes the electrodes 1 carry out reciprocating motion by controlling control motor of the electrodes 1 thru the control circuit 9. The detected pulse at the encoder 16 is counted at the up-down counter 12, detecting the position of the electrodes 1, while at the comparator 13, the two signals i.e. (a) signal at the latch circuit 11 which memorizes the number of count at the counter 12, and (b) changing count output at the counter 12, are compared and the processing pulses are stopped at the moment when the motion of expanding the processing clearance of electrodes is started, and the supply of processing pulses is resumed when the position of stopping the motion comes to coincide with that of starting the motion.