| 摘要 |
PURPOSE:To enable the current and voltage characteristic of electric discharge to be varied by connecting a starting intermediate electrode, which is provided for facilitating the starting of the electric discharge of a hollow cathode, and an anode by means of resistances. CONSTITUTION:A main anode 2 is installed facing a hollow cathode 1. An electric-discharge starting electrode 4 is installed near the opening hole of the orifice part 3 of the hollow cathode 1. Both the hollow cathode 1 and the starting electrode 4 are connected to a starting power source 6 through a limiting resistance Rk5. Both the hollow cathode 1 and the main anode 2 are connected to an arc power source 8 through a limiting resistance RA7. In addition, both the starting electrode 4 and the main anode 2 are connected to a resistance RB10 through a diode 9. In general, the capacity of the starting power source 6 is around (300V-500V)X1A, that of the arc power source 8 is (100-150V)X(necessary arc current), and the insulation of the arc power source 8 is lower than that of the starting power source 6. The diode 9 is provided for the protection of the arc power source 8. If the arc power source 8 resists the voltage of the starting power source 6, the diode 9 is unnecessary. |
