| 摘要 |
PURPOSE:To realize precision finish with fine surface roughness by interconnecting Gunn diodes in parallel near an electrospark machining gap connected to a DC power supply and further providing a switch in parallel to said diodes which switch is closed in short circuit. CONSTITUTION:A DC power supply 3 is connected to an electrospark machining gap constituted from an electrode 1 and a work 2, and Gunn diodes 4, 5 are connected in parallel to and near said gap. The polarity of the Gunn diodes 4, 5 is changed over by a change-over switch 6 according to the polarity of the DC power supply 3. When the field strength applied to Gunn diodes 4, 5 exceeds a predetermined value, the Gunn diodes 4, 5 start to generate high frequency of about GHz, this high frequency pulse being applied to the working gap to carry out electrospark machining of precision finish with fine surface roughness. Short circuit and arc discharge are detected by a control circuit 8 to close a switch 7 for stopping said machining. |
