JPS57181971A - Non-contact ignition system for magnet generator type internal combustion engine - Google Patents

Abstract

PURPOSE:To suddenly delay an ignition timing at a high revolution speed by providing a supplementary capacitor which bypasses an ignition signal of a signal convesion circuit, a revolution detective circuit and an amplifier circuit for an ignition system of a magnet generator type to actuate a transistor in association with increase in revolution speed. CONSTITUTION:When a revolution speed is increased, an ignition signal bypasses a supplementary capacitor 15, which provides gradual ignition delay characteristics. When a positive power is generated at a main capacitor charging coil 1, a supplementary capacitor 16 is charged with a certain voltage to get a polarity shown by the drawing. When a negative power is generated at the coil 1, a transistor 18 is conducted so that a supplementary capacitor 17 is charged with electric load accumulated in the supplementary capacitor 16 to get a polarity shown by the drawing and a voltage proportional to the revolution speed appears at the terminal of the capacitor 17. In a low-revolution range, a transistor 19 is off and when the revolution reaches a high speed range, an electric charge sufficient for turning the transistor 19 on is accumulated in the supplementary capacitor 17. Accordingly, the capacitor 17 is turned on and the ignition signal is bypassed, so that an ignition timing is rapidly delayed. When the revolution speed is increased up to the maximum, the rapid ignition delay ends.