GB191505079A - Improvements in and in connection with Dynamo Electric Machines. - Google Patents

Abstract

5079. Boin, R. April 1. Magneto-electric machines; exciting.-A machine for supplying current for engine-ignition, lighting, and battery-charging on a motor-vehicle &c., and capable of acting as a motor for starting the engine, comprises a single armature a having one or more windings and a permanent field magnet d, each pole of which has two or more pole-pieces e, f and e', f<1> provided with regulating-windings. In one form, Fig. 3, the armature has a coarse-wire or motor winding with commutator brushes b<1>, b', and a fine-wire or generator winding with brushes c', c<2>, and the pole-pieces are provided with windings g, h, some turns h<1>, h' of the winding h being wound reversely upon the pole-pieces f, f<1>. To run the machine as a motor in starting the engine, the switch j is turned against the contact j<1> so as to connect the brushes b<1>, b<2> with the battery i, the windings g, h then acting in conjunction to strengthen the field of the permanent magnet. In a modification, both armature windings may act as motor windings. When the engine has started, the switch j is moved against the contact j' so as to connect the brushes c', c' to the battery, the current generated in the coarse-wire armature winding then circulating through the winding g in the reverse direction to the current in the winding h. The pole-pieces f, f<1> now change sign, the poles f, e<1> now being, say, South poles, and the poles e, f<1> North poles; the field axis is thus displaced, instead of the brushes. Both armature windings may be coupled in series when the machine acts as a generator. The induction coil l for engine-ignition has an interrupter o in its primary circuit; the induction coil is placed in circuit by means of a switch p either with the battery i or, when the battery is discharged and the engine is being started by hand, with the generator brushes c<1>, c'. The interrupter and distributor are actuated by the countershaft t.