GB587338A - Improvements relating to electric ignition systems for internal combustion engines - Google Patents

Abstract

587,338. Ignition systems. LUCAS, Ltd., J., and LAIRD, J. A. Jan. 5, 1945, No. 503. [Class 7 (iv)] In an ignition system of the type having a main condenser d charged by an electromagnetic source and discharged through the primary of a transformer the secondary of which is connected to a sparking plug or plugs the charging of the condenser takes place through a charging gap e and discharge is effected by a three electrode discharging gap j having connected to its middle electrode a second condenser k the other side of which is connected to a point between the charging gap and the source. In the arrangement shown a magneto charges the main condenser d through the gap e and the second condenser k through the lower half of the gap j which lower half has a breakdown voltage of about one half the voltage to which the main condenser is charged. The breakdown voltage of the upper half of the gap j is greater than the voltage to which the condenser is charged. When the charging of the two condensers ceases the two gaps isolate the condensers from the magneto. While the voltage of the magneto is falling the voltage across the gap j due to the combined effects of the condensers d, k is sufficient to cause breakdown of the upper half of the gap and consequent discharge of the condenser through the primary winding f. The transformer secondary may be connected to the sparking plugs through a distributor or there may be a separate transformer for each sparking plug connected to the condenser circuit through the distributor. Specification 529,558 is referred to.