GB271592A - Improvements in and relating to magneto electric machines - Google Patents

Abstract

271,592. British Thomson-Houston Co., Ltd., and Young, A. P. March 15, 1926. Magneto-electric machines.-A magneto for producing multi-point ignition in each cylinder of an internal-combustion engine comprises a number of stationary coils with associated distributing means, and a continuous ring magnet rotor. Fig. 2 shows a construction adapted to give two-point ignition in a three cylinder engine. The rotor 5 has six poles and the armature two coils 6, and the distributer 7 which is mounted on the rotor shaft has six terminals. In this arrangement, the contact breaker has a three point cam, but by employing a six point cam, two-point ignition in a six cylinder engine may be obtained. To protect the magnet poles against demagnetization, thearmature cores have extensions 9 surrounding the rotor. In Fig. 3, a modified distributer for twopoint two cylinder ignition comprises two slip-rings 19, 20 upon which bear brushes 17, 18 connected to the secondary windings of the coils 15, 16. The rings carry contact arms 21, 22 which cooperate with electrodes 23, 24 connected to the sparking plugs 25, 26. The Specification describes a twelve cylinder twelve-point magneto having an internal rotor, and a six cylinder sixpoint magneto having an external rotor. Where three or more ignition points per cylinder are required, the distributer preferably is provided with a corresponding number of slip-rings. Such a distributer, similar to that shown in Fig. 3, isdescribed for three cylinder three-point ignition. Specifications 138,081 and 214,682 are referred to.