GB824131A - An internal combustion engine embodying a high tension polar induction flywheel ignition magneto - Google Patents

Abstract

824,131. Dynamos. BOUNDY, F. J. Nov. 20, 1956 [Nov. 25, 1955], No. 35509/56. Class 35. An I.C. engine embodies a H.T. polar induction flywheel ignition magneto comprising a permanent magnet 9 and a plurality of associated laminated polepieces 10, 10a about which the engine crank-shaft 1 ... 4 and 7 is cast and which rotate within the engine crankcase 8 which is cast about a plurality of fixed laminated polepieces 12 past which the rotating polepieces 10, 10a move to change the flux therein, an armature winding 14 carried by a fixed polepiece 12 and in which a voltage is generated by the change of flux, and means in the crankcase wall to reduce eddy current flow about the fixed polepieces, the crank-shaft and crank-case being of non-ferrous metal. As shown, the magnet 9 and polepieces 10, 10a are in the crank disc 2 and the shaft 7 has an integral cam 7a operating an interrupter, not shown, connected in the armature winding primary circuit. Detachably connected at the outer ends of the fixed polepieces 12 is a transverse laminated bridging member 13. The means reducing the eddy current flow are either, Fig. 1, slots 15 and a recess 17 which may be filled with an electrically insulating material, e.g. phenolic resin, or, Fig. 2, a thin sheet 18 of dielectric material, e.g. asbestos, disposed between the fixed polepieces 12 and intermediately of their stacks. The invention is applicable to two- or four-stroke engines.