| 摘要 |
PURPOSE:To improve the efficiency of spark machining, by detecting the displacement speed of an electrode and an actual electrical current contributing to the spark machining and by calculating a processed area from the detected values to alter electric conditions for the spark machining. CONSTITUTION:A pulse voltage is applied from a power source 3 across a workpiece 2 and an electrode 1 to process the workpiece by spark machining. The voltage across the spark gap is detected by an integrator 4, compared with a reference voltage V1 and changed into an electrode servo-displacement signal through a V-F converter 6. Only when proper discharge is caused, an analogue switch 8 is turned on by the output of the integrator 4 and the detected value of the processing electrical current is integrated by an integrator 9. A controller 11 calculates a processed area from the output of the integrator 9 showing the value of the actual processing electrical current and that of the V-F converter 6 showing the velocity of the processing. Electric processing condition altering signals b, c, d for the power source 3 are generated on the basis of the result of the calculation by the controller 11. |
