| 摘要 |
PURPOSE:To prevent secondary discharge in discharge processing and improve tapering performance on a work by switching the processing on by detecting that discharge processing electrode has reached in the neighborhood of depth having already been processed. CONSTITUTION:A hole is bored on a work 12 by making a discharge to take place between and electrode 11 and the work 12. Since a dischrage usually takes place in oil, it is necessary to keep removing sludge which generates with progress of hole-boring process, and therefore, whenever this occurred, the electrode 11 is pulled up by a periodical pull-up step 7 and at the same time the discharge is stopped. When the electrode 11 is lowered to re-start discharge processing, a depth detecting circuit 10 detects and confirm that the electrode 11 has reached in the neighborhood of the depth having already been processed, and then actual processing by discharge is started. |
