| 摘要 |
PURPOSE: To form a ball by controlling the diameter of a ball adequately when the current setting value is changed. CONSTITUTION: A discharge voltage detector 7 detects the voltage of the discharge between the end of a wire 1 and an electrode 3. A discharge current detector 8 detects the current of the discharge and both the detected voltage and current are sent to an integrator 9. The integrator 9 multiplies the detected voltage and current by the predetermined gain, integrate them in time base, and sent the integrated values to a ball diameter judging part 13. The ball diameter judging part 13 estimates the diameter of the ball from the output of the integrator 9 and operates an discharge controlling part 12, comparing the estimated diameter of the ball with the set diameter 11 of the ball being given to the ball diameter judging part 13 separately, until it becomes equal with the set diameter 11 of the ball. A ball diameter correcting part 14a controls the predetermined gain of the integrator 9. The output of the integrator 9 estimates the diameter of the ball accurately when the discharge current is changed. |
