Abstract: An exciter circuit for an ignition system including an igniter plug. The exciter circuit includes an energy storage device comprising a pair of capacitors and a charging circuit for charging the capacitors of energy storage device to a predetermined voltage. The exciter circuit further includes a discharge circuit electrically coupled to the energy storage device and the igniter plug providing a conductive path between the energy storage device and the igniter plug. The exciter circuit periodically energizes the igniter plug by applying an output signal of the discharge circuit to the igniter plug, the output signal having a voltage magnitude sufficient to initiate a spark across electrodes of the igniter plug.

Abstract: An ignition system exciter circuit includes a storage capacitor; a charging circuit for charging the capacitor; a discharge circuit connectable to an igniter plug; and a first switching circuit for controlling discharge of the capacitor through the discharge circuit and plug; the discharge circuit comprising a step-up transformer for transforming voltage stored on the capacitor to a higher voltage across the igniter plug when the first switching circuit is closed; the transformer having a primary winding and a secondary winding, with the secondary winding having a first terminal that can be coupled to a first terminal of the igniter plug and a second terminal that can be coupled to a second terminal of the igniter plug; and a second switching circuit that is responsive to a voltage transition across the igniter plug and that prevents the transformer primary and secondary windings from conducting spark discharge current.

Abstract: An oscillatory discharge exciter includes an input connectable to a power supply; an output connectable to an igniter; at least two energy storage elements for producing an oscillatory discharge of energy during an exciter discharge period; a unidirectional gated switch and a rectifier coupled in reverse parallel with each other such that the switch and rectifier control, during respective alternating half cycles, oscillatory discharge energy at the exciter output; and a circuit for gating the switch in response to voltage transitions across the switch. The gating circuit can also be used as a snubber circuit to add gate drive to slow devices, as well as to trigger a series of switching devices with the application of only a single external trigger signal to one of the devices. In an alternative embodiment, the gating circuit is replaced with a circuit for maintaining holding current through the switch to prevent the switch from recovering to a blocking condition.

Abstract: An ignition system for a gas turbine engine includes a plurality of igniters, an energy storage capacitance, a charging circuit for charging the capacitance, a plurality of gated switches, with at least one switch connected between each igniter and the capacitance, and control means for discharging respective amounts of energy from the capacitance to each respective igniter at respective spark rates.

Abstract: An exciter for an internal combustion engine igniter plug includes a charging circuit and a discharge circuit; the charging circuit being connectable to a power supply and the discharge circuit being connectable to the plug to produce sparks; the discharge circuit comprising a storage capacitor connected to the charging circuit, a gated solid state switching device connected between the capacitor and the plug, and a trigger means for gating the switching device on and off; the capacitor being discharged when the switching device is gated on and the capacitor being charged by the charging circuit after the switching device is gated off.

Abstract: An exciter for an internal combustion engine igniter plug, comprises a continuous AC charging circuit and a discharge circuit. The discharge circuit is connectable to the plug and the charging circuit includes a transformer having a primary winding connectable to an AC power source and a secondary winding connected to the discharge circuit. The discharge circuit includes a storage capacitor connected to the transformer secondary winding such that current induced in the secondary charges the capacitor at a generally constant rate. A switching device is connected in series between the capacitor and the plug; and a trigger circuit triggers the switching device in response to charge on the capacitor; with the charging circuit and trigger circuit operating to maintain a generally constant spark rate. A current multiplier is also provided to substantially increase the peak currents delivered to the plug.

Abstract: A system and method for providing a constant rate of sparking in the spark gap of an internal combustion engine by supplying constant power to the capacitor which discharges through the spark gap. The capacitor receives current from the secondary coil of a transformer. The system uses a multivibrator to control current flow through the primary circuit of a transformer. The multivibrator is controlled by a comparator which compares an integrated transformer feedback signal to a temperature compensated reference voltage. In any two equal time periods, substantially the same amount of current flows to the capacitor from the secondary of the transformers. Substantially the same number of sparks are discharged through a spark gap during equal time periods.