GB171145A - Improvements in and relating to magneto-electric machines - Google Patents

Abstract

171,145. British Thomson - -Houston Co., Ltd., and Young, A. P. Aug. 3, 1920. Magneto-electric machines. - In an ignition magneto for four-cylinder machines of the type in which the secondary winding is connected intermittently to two of the cylinders in series and then to the other two, one spark being wasted at each discharge, the current is taken from the secondary winding by collectors adapted to receive a " jump-spark " instead of by brushes. For this purpose the ends of the secondary winding are connected to conducting segments 7, 8 embedded in an insulating ring 6 on the armaturespindle, and collectors 9, 9<1>, 10, 10' are arranged to take " jump-sparks " from these segments in the appropriate order as shown in Fig. 3. The collectors 9, 9<1> are connected through the sparking- plugs 13, 15 of two of the cylinders, as shown in Fig. 4, and the collectors 10, 10<1> through the sparking plugs 12, 14, of the other two cylinders. The field magnet is preferably formed of a bar magnet 3 of cobalt steel or the like, to which are secured soft iron plates carrying laminated polepieces.