JPS55157435A - Wire-cut electric discharge machine - Google Patents

Abstract

PURPOSE:To prevent an outflow of machining liquid from the concaved part of a table of an electric discharge machine and perform the unmanned operation of the machine, by allowing the detecting means to detect a filled-up state of the concaved part with the machining liquid and stopping the electric discharge machine. CONSTITUTION:When failures of a discharge pump 17 causes machining liquid 13 not to be discharged into a machining liquid containing tank 3 and raise its level enough to fill a concaved part 15 for accepting the machining liquid, a float switch 27 generates a signal (c) of full machining liquid. While in a magnetic tape 18, a completion signal of machining is recorded correspondingly to the completion of preset shifting motion of a table 1, and a tape read unit 19 generates a completion signal (d) of machining when it reads said signal. A safety device 32, that controls a contact 31 for connecting a feed pump 12, discharge pump 17, electric discharge machining power source 28, etc. to the external power source, when it receives at least one of the signals, disconnection signal (b), signal (c) and signal (d), allows the contact 31 to stop the electric discharge machine.