| 摘要 |
1,092,333. Semi-conductor switching circuits. ENTWICKLUNGSANASTALT FUR INDUSTRIE-ELEKTRONIK Feb. 12, 1965 [Feb. 13, 1964], No. 6228/65. Heading H3T. In a supply circuit for an electromagnetic vibrator, the winding of the vibrator is connected in series with a semi-conductor controlled rectifier (S.C.R.) across an A.C. supply. The S.C.R. is shunted by an ohmic resistor, arranged to pass a current of the order of the S.C.R. holding current, before the S.C.R. is triggered by phase-adjustable pulses. The build-up of current in the winding is thus facilitated. Over-voltage protection is provided by a pair of Zener diodes or by a bridge rectifier feeding a capacitor. |
