| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a wire electric discharge machine little effected by variations in a detection circuit of inter-electrode voltage. <P>SOLUTION: An electric discharge ratio and an opening ratio per unit time are mostly determined in accordance with the opening ratio per unit time from an experiment of measuring the inter-electrode voltage and determining the discharge state, furthermore, the relationship changes very little among the machines. Consequently, only with detection of a clearly distinguishable opening state, electric discharge frequency and short circuit frequency per unit time are estimated. A trapezoidal wave voltage is applied between the electrodes during one application cycle, an intermission time is provided after voltage application, and the opening state is determined during the intermission time when the wire electric discharge machine is little effected by the variations in the detection circuit. An inter-electrode average voltage is determined based on the opening ratio for the application cycle frequency of the detected opening state and on a power supply voltage and the average voltage of one application cycle. By applying the conventional feed control using the frequency of the discharge thus found and the average voltage found from the opening ratio as indexes, highly precise machining can be actualized even in a high frequency machining. <P>COPYRIGHT: (C)2012,JPO&INPIT |
