GB585776A - Improvements relating to electric spark ignition systems for internal combustion engines - Google Patents

Abstract

585,776. Ignition systems. LUCAS, Ltd., J., and LAIRD, J. A. Nov. 24, 1944, Nos. 23469/44 and 166/45. [Class 7 (iv)] An ignition system for an internal-combustion engine of the kind in which the spark at the plugs i is produced by the discharge of a condenser. b through a transformer g, h, Fig. 2, or successively through a number of transformers, Fig. 1, has a pair of two-electrode sparkgaps c, d arranged in the circuit, one terminal of the gap c being connected to one side of an alternating current source such as a magneto a and the corresponding terminal of the gap d to the other side of such source, the other terminal of the two gaps being connected to the condenser b and the spark voltage of each gap being greater than the voltage to which it is required to charge the condenser. The gap c preferably has a higher sparking voltage than gap d. Thus if the condenser has to be charged to 3 KV the spark voltage of the gap c may be 8 KV and of gap d 4 KV. Another condenser e may be put across the magneto secondary. If the distributor f of Fig. 1 is of the jump spark type, a choke j may be located as shown. In a modification the first terminal of gap d is connected to the source through a transformer primary or, Fig. 4, successively through a nuniber of primaries. In these cases a second condenser e is preferably included. In another modification, Fig: 6, a high frequency choke m may be inserted between adjacent electrodes of the gap c, d. Specifications 490,392 and 529,558 are referred to.