High frequency ignition system for aircraft engines and the like

Claim 1

A HIGH FREQUENCY ELECTRICAL IGNITION SYSTEM FOR INTERNAL COMBUSTION ENGINES OPERABLE OVER A WIDE R.P.M. RANGE, SAID ENGINE HAVING A PLURALITY OF COMBUSTION CHAMBERS WITH CORRESPONDING SPARK PLUGS, COMPRISING (A) A DYNAMO-ELECTRIC DEVICE HAVING AT LEAST TWO ELECTROMAGNETIC GENERATORS FOR PRODUCING RESPECTIVE SUPPLY VOLTAGES, EACH GENERATOR BEING DRIVEN THROUGH A COMMON CONNECTION WITH THE ENGINE AND OPERATING ACCORDING TO A DIFFERENT R.M.P.-VOLTAGE CHARACTERISTIC CURVE, (B) AN ELECTRICAL CONTROL NETWORK FOR EACH SPARK PLUG INCLUDING A CONDENSER, AND A PULSE TRANSFORMER FOR RECEIVING THE CONDENSER DISCHARGE CURRENT, (C) SAID NETWORK BEING ENERGIZED JOINTLY BY SAID SUPPLY VOLTAGES FOR CHARGING SAID CONDENSER AT A PREDETERMINED MINIMUM LEVEL OF CHARGING VOLTAGE THROUGHOUT THE ENGINE SPEED RANGE IRRESPECTIVE OF VARIATION IN ENGINE R.P.M., AND (D) SWITCHING MEANS RESPONSIVE TO ENGINE SPEED FOR CONTROLLING THE PERIODIC DISCHARGE OF SAID CONDENSER THROUGH THE PRIMARY OF ITS ASSOCIATED PULSE TRANSFORMER FOR PRODUCING TIMED DURING OF THE CORRESPONDING SPARK PLUG.