GB1330505A - Pulse generating apparatus - Google Patents

Abstract

1330505 Ignition systems BENDIX CORP 24 Sept 1970 [25 Sept 1969] 45598/70 Addition to 1330503 Heading F1B [Also in Division H3] A pulse generator comprises a supplementary condenser 31 of smaller capacity than a main condenser 20 and a first gap 36 having a breakdown potential less than that of a second gap 25 the main and supplementary condensers are charged in parallel from input terminals from a uni-directional voltage source 15, 16, 17 and 19 until the first gap 36 breaks down so as to connect the condensers 20, 31 in series across the second gap 25 which then breaks down and output terminals are thereby connected through the second one 25 only of the gaps across the main condenser 20 and the primary winding 35 of a voltage step-up transformer 28 is connected by the first gap 36 in the series circuit comprising the main and supplementary condensers 20, 31 and the secondary winding of which is connected in series the circuit comprising the main condenser, the second gap 25 and the output terminals. Source 13, such as A. C. or interrupted D.C. is supplied via RF filter 14, transformer 11 and a voltage doubling circuit 15-17, 19, 22 to charge the condensers 20, 31. When the trigger gap 36 breaks down the condensers 20, 31 are connected in series with the primary 35 of the step up transformer 28 and the control gap 25 which becomes ionized and conducts. The output voltage generated at secondary 27 causes an arc across the igniter plug 29 such as of a jet or gas turbine engine and the condenser 20 discharges through the control gap 25, winding 27 and through the pre-formed arc of the ignition gap 29. The voltage across the condensers 20, 31 then falls and the gaps 25, 36 are de-energized such that the cycle is repeated. The diodes 16, 19 are protected against damage by limiting resistors 21, 22. The voltage doubling circuit may be replaced by a rectifier, Specification 1330504 is referred to.