| 摘要 |
PURPOSE:To enable a sputter ion pump power supply to operate safely regardless of its output load by detecting spark discharge. CONSTITUTION:A d.c. voltage relay 7 has the function of inactivating a switching circuit 2. A switch 8 has the function of inactivating the d.c. voltage relay 7. A signal detector 11 has the function of inactivating the switching circuit 2 by utilizing pulse signals detected by a current transformer 10. When continuous spark discharge develops, the output voltage of a high-voltage contact plug 9 has the wave form (a); the voltage (VB) is a voltage necessary for initiating the electric discharge of a dielectric breakdown part. The output current produced at this point has a pulse-like wavy form and is detected with the current transformer 10. In contrast, during the normal electric discharge, a d.c. current flows and the current transformer 10 is inactivated. The current having a pulse-like wavy form and detected with the current transformer 10 is then converted into a d.c. voltage by means of the signal detector 11. The thus produced d.c. voltage drives the relay and the like of the signal detector 11 to inactivate the switching circuit 2 thereby cutting off a commercial input power supply 1. |
