| 摘要 |
PURPOSE:To enable a short-circuit between an electrode and a work due to the cutting of electric discharge machining to be prevented by allowing the electrode to jump. CONSTITUTION:When a work is moved by a motor 105 in accordance with NC data of a tape 101 and machined by an electrified electrode EP, if a short-circuit between the electrode and the work is caused by the cutting of a machine, a short-circuit signal SS is input to an input/output board 102f, and a processor 102a interrupts execution of a machining control program but executes the program of a program memory 102b through a bus 102i. In this way, a backward pulse BS in the reverse direction is generated from a pulse distributor 103, and the content of an error register 107b becomes zero after a prescribed time, causing the electrode EP to move backward and jump by the backward pulse. If the short-circuit is released, the signal SS disappears while the processor 102a detects disappearance of this signal, causing the electrode EP to advance and restart its machining feed. |
