PURPOSE: To produce uniform aventurine surface by detecting the condition between the poles through the ratio of discharging frequency of low voltage pulse out of the high and low voltage pulse impressed in the machining space.
CONSTITUTION: In the machining space between a roll 1 and an electrode 2 are impressed high and low voltage pulses in mixture, but the low voltage pulse is scarce compared to the high voltage pulse. A detector circuit 12 detects the discharged current at time of low voltage pulse impression, and the condition between the poles is detected at an inter-pole condition detector circuit 13 according to the number of discharged low voltage pulse out of n such pulses; then, the electrode feeding amount being decided, the electrode feeding device is operated by a driving circuit 14. Since the low voltage pulse does not contribute to the machining, and the peak value and the width of the low voltage pulse can be determined arbitrarily, the machining space can be controlled at the most appropriate length, securing very efficient machining, and no stripe pattern is produced even when the space is changed due to vibration etc.
URATA TETSUO
NISHIKAWA MORIHISA
KAMIUMA TERUMASA
KAWANO MITSUGI
KAMIBAYASHI TAKEO
NIPPON KOKAN KK
| JPS5426598A | 1979-02-28 |