Breakerless ignition system

Claim 1

A breakerless ignition system for an internal combustion engine comprising a DC power source, a multistage transistor amplifier circuit, the collector-emitter circuits of the transistors being in parallel across said power source, means interconnecting the base of each transistor after the first state transistor to the collector-emitter circuit of the preceding stage transistor whereby conduction of a transistor at one stage will place the base of the succeeding stage transistor at substantially ground potential to prevent conduction thereof, The number of stages being even whereby the final stage transistor and first stage transistor conduct alternately, a step-up transformer having a primary winding and a secondary winding, the primary winding being in the collector-emitter circuit of the final stage transistor, a voltage dividing network connected to the power source and to the base of the first stage transistor, the voltage available to said base via the network being insufficient to bias the first stage transistor to conduct, a photocell between the voltage dividing network and the base of the first stage transistor, said voltage dividing network comprising a resistor and a continuously conducting diode, in that order, in series between the power source and ground, the base of the first stage transistor being connected between the resistor and diode, a light source, means to repetitively impinge light from said light source onto the photocell in timed relation to engine operation to energize the photocell whereby the photocell will develop a voltage which is added to the voltage of the voltage dividing network to bias the first stage transistor to conduct, conduction of the first stage transistor resulting in cutoff of the final stage transistor and collapse of the magnetic field in said primary winding to induce a voltage in the secondary winding sufficient to fire a spark plug of an internal combustion engine.