| 摘要 |
1,223,733. Starting discharge lamps. PHILIPS ELECTRONIC & ASSOCIATED INDUSTRIES Ltd. 27 Sept., 1968 [30 Sept., 1967], No. 46024/68. Heading H2H. A starting arrangement for a discharge tube 4 having preheated electrodes 5, 6 comprises an inductor 3 in series with the tube 4, a semiconductor controlled rectifier 9 connected across those terminals of the tube remote from the input terminals, a control circuit for the rectifier 9 and a capacitor 8 in series with a resistor 7 connected across the tube. The control circuit may comprise a disc 12 connected between the control electrode of the rectifier 9 and the junction of a resistor 10 with a capacitor 13 and a resistor 11. When the A.C. supply is switched on, the disc 12 becomes conductive when the capacitor 13 is sufficiently charged. This causes the rectifier 9 to conduct so short-circuiting the rectifier, the subsequent cessation of the current through the rectifier effecting the removal of the short circuit so that the capacitor 8 can charge rapidly and produce a high ignition voltage. |
