GB1239817A - Electrical pulse generating apparatus for engine ignition - Google Patents

Abstract

1,239,817. Pulse generating circuits. BENDIX CORP. 1 Aug., 1968 [29 Aug., 1967], No. 36671/68. Heading H3P. [Also in Division F1] An electrical pulse generating apparatus for the ignition of jet or gas turbine engines comprises a combination of a first circuit 5 and a second circuit 6 for supplying to the engine igniter device either high energy pulses for engine starting or low energy pulses for engine operation. The igniter device includes two series connected igniter plugs 21, 22 which are both supplied with the high energy pulses whereas only one of the plugs is supplied with low energy pulses during engine operation, the circuits having a common high frequency coil through which either high or low energy pulses can be supplied to the one igniter plug. The triggering gap 23 is rendered conductive to the discharge of the capacitor 11 through the primary winding 14 to thereby induce a sufficient voltage across the secondary winding 31 to render the control gap 32 conductive to discharge of the capacitor 8. Once the engine is started by high energy sparks resulting from discharge of the capacitor 8, switch 7 is opened to de-energize the high energy circuit 5 and switch 17 is closed to energize the continuous duty low energy circuit 6 wherein discharging of the capacitor 18 is controlled by a sealed gap 36. High tension igniter plugs could be used in lieu of the low voltage plugs illustrated and the inductors 34 and 35 could be replaced by gaps.