Engine ignition transistorised unit - has charging time of ignition coil independent of engine speed and uses two capacitors

摘要

An internal combustion engine ignition unit is transistorised and has a charging time independent of the speed of the engine. The ignition unit is supplied by the battery of a car and fitted between the contact-breaker (1) and the primary (2) of the ignition coil. A capacitor (18) is charged at a voltage set by resistors (15, 16, 17) and the opening and closing times of the breaker (1). Another capacitor (19) is charged at the same voltage as the first capacitor (18). A comparator (20) and a circuit comprising the primary (2) excites the coil when the voltage of the second capacitor (18).