| 摘要 |
PURPOSE:To miniaturize a contactless ignition device of capacitor discharge type with simple construction, by providing a semiconductor switching element substantially short circuiting half wave output of a capacitor charging coil. CONSTITUTION:When charge side half wave output is generated in a capacitor charging coil 3, a base current flows in a transistor 12 througha resistor 13, and the transistor is electrically conducted across its collector and emitter, then the output of the coil 3 is short circuited. An increase of this short current causes a large voltage drop to increase voltage at a point (a), if becoming a preset value, a thyristor 14 is electrically conducted to short circuit across a base and emitter, and the transistor is turned off and rapidly cut off to generate large induction voltage in the coil 3 and charge a capacitor 6. Then immediately, the induction voltage is decreased to less than the charge voltage, and a thyristor 10 is conducted by a discharge current to flow the discharge current in a primary coil 7a, then high voltage is generated in a secondary coil 7b to obtain an ignition spark. |
