| 摘要 |
1,204,460. Ignition systems. FORD MOTOR CO. Ltd. July 21, 1969 (Aug.1, 1968], No. 36535/69. Heading F1B. An ignition system comprises an inductor 176 connected in series with a source of direct current 26 and adapted to be charged to a predetermined current level for providing a predetermined energy charge to a spark plug 24, means 164 for interrupting current through the inductor, a capacitor 134 connected to the source of direct current, means 150 coupled to the capacitor for limiting the voltage across the capacitor to a predetermined voltage level lower than the voltage of the source, means coupled to the capacitor and the source of electrical energy for causing the capacitor to charge to the predetermined voltage level at the same time as the current through the inductor reaches the predetermined level and means coupled to the inductor, to the capacitor and to the means coupled to the capacitor for limiting voltage across the capacitor for interrupting current through the inductor when the predetermined voltage across the capacitor is reached. When the Zener breakdown voltage of the Zener diode 150 is reached current flows through it in the reverse direction and into the base of the transistor 116 thereby switching transistor 116 to a conducting state. This turns transistor 120 off since the base current into the base 144 is diverted through the collector 140-emmitter 136 of the transistor 116. When the transistor 120 is turned off transistors 152 and 164 are switched to the non-conducting states. When transistor 164 is switched to its non-conducting state current is interrupted through the inductor or primary winding 176 of transformer 178 and the inductively stored electrical energy is transferred to the capacitor 192. |
