To provide a wire electric discharge machine equipped with an inter-electrode state detection function that is hardly affected by variation.
An electric discharge ratio and opening ratio per unit time are mostly decided in accordance with the opening ratio per unit time. As a result, the electric discharge ratio per unit time is mostly decided in accordance with the opening ratio per unit time, and there is little difference among machines. Accordingly, only a clearly distinguishable opening state is detected to estimate electric discharge frequency and short circuit frequency per unit time. A trapezoidal wave voltage is applied between electrodes during one application cycle, quiescent time is provided after voltage application, and the opening state is determined during the quiescent time. An inter-electrode average voltage is determined from the opening ratio for the application cycle frequency of the detected opening state and from a power supply voltage and the average voltage of one application cycle. To the wire electric discharge machine, a feed control using the electric discharge frequency thus obtained and the average voltage obtained from the opening ratio as indexes is applied.
MURAI MASAO
FURUTA TOMOYUKI
| JPH0197522A | 1989-04-17 | |||
| JPH0938829A | 1997-02-10 | |||
| JPH08118146A | 1996-05-14 | |||
| JPS63185521A | 1988-08-01 |
| WO2003106088A1 | 2003-12-24 | |||
| WO2005072900A1 | 2005-08-11 | |||
| WO2002058874A1 | 2002-08-01 |