GB1386192A - Inductive storage ignition systems for internal combustion engines - Google Patents

Abstract

1386192 Ignition systems BROWN BOVERI & CIE AG 25 Jan 1973 [28 Jan 1972] 3893/73 Heading F1B An inductive ignition system for an internal combustion engine includes a high voltage circuit including a secondary winding 5 of an ignition coil, a low voltage circuit including a primary winding inductively coupled to the secondary winding, the primary winding comprising a first low resistance section 3 and a second high resistance section 4 connected in series with the first section, means for sequentially energizing the first section and the second section of the primary winding from a D.C. power source 10 and a diode 8 connected in series with the second section to prevent current flow therein as a result of voltage induced in the second section by current flow from the power source in the first section. When the contact breaker switch 1 is closed an initial current i 1 flows in the windings, 4, 3 and induces a voltage in the winding 11. This causes a current i 2 to flow to cause the transistor 12 to conduct. This provides a charging current i 3 to the winding section 3. The charging current rises to a peak value of for example 12 amps. When this value is reached the common core of the windings 5, 6 and 11 is saturated as a result the current i 2 ceases and the transistor 12 returns to its blocked state. When the current through the winding section 3 ceases a current I H is establised through the winding sections 4, 3. This current acts as a holding current. Opening of the contact breaker switch 1 results in a flow of current in the high voltage circuit 5 and a spark at one of the sparking plugs 9. A simplified embodiment and an embodiment including two control transistors are described. The/or each transistor can be replaced by a thyristor.