GB1130532A - Ignition circuit with voltage regulator - Google Patents

Abstract

1,130,532. Ignition systems. TUNG-SOL ELECTRIC Inc. Jan. 18, 1966 [Feb. 24, 1965], No. 2354/66. Heading F1B An ignition system comprises a pair of breaker contacts 12 connected in series between a source of power 10 and a resistor 21, a charging transformer, the secondary winding 34 of the charging transformer being connected to a high voltage utilization circuit adapted to generate voltage pulses each time the breaker contacts are opened; a silicon controlled rectifier 40 having an anode, a cathode and a control electrode adapted to make the anode cathode circuit conductive when activated by a positive pulse, an inductor connected in series with the primary winding 33, the source of electrical power and the anode cathode circuit of the silicon controlled rectifier, a first control circuit having its input circuit connected across the breaker contacts and its output circuit connected across the control electrode of the silicon controlled rectifier and its anode the first control circuit being adapted to generate a positive pulse in its output circuit when the breaker contacts 12 are opened a second control circuit having input terminals coupled to the primary winding 33 through the inductor and to the cathode of the silicon controlled rectifier, the second control circuit including a three terminal semi-conductor switch for switching the current through the primary winding, two terminals of which switch are connected to the output terminal of the second control circuit, the second control circuit also including a voltage reference component responsive to the peak value of the current in the primary winding and electrical coupling means between the voltage reference component and the semi-conductor switch. As shown the the voltage on the Zener diode 57 is fixed and the capacitor 54 is charged from the input power source (battery 10) when the voltage is high the capacitor is charged quickly and the unijunction transistor 53 is fired a short time after the transistor 55 is made conductive. During this time interval the current in winding 33 rises to a desired peak value. When the battery voltage is low the capacitor is charged slowly and the unijunction transistor 53 is fixed a longer time after transistor 55 is made conductive. During this longer time interval the current in winding 33 rises to the same desired peak value. The switching device 45 may be either a gas filled thyratron or a silicon controlled rectifier. A modified circuit is described with reference to Fig. 2 (not shown).