Nikola Tesla - Free-Energy Devices

CHAPTER IX.CHANGE FROM DOUBLE CURRENT TO SINGLE CURRENT MOTOR.A DESCRIPTION isgiven elsewhere of a method of operating alternatingcurrent motors by first rotating their magnetic polesuntil they have attained synchronous speed, and then alternatingthe poles.The motor is thus transformed, by a simple changeof circuit connections from one operated by the action of two ormore independent energizing currents to one operated either bya single current or by several currents acting as one. Anotherway of doing this will now be described.At the start the magnetic poles of one element or field of themotor are progressively shifted by alternating currents differingin phase and passed through independent energizing circuits, andshort circuit the coils of the other element. When the motorthus started reaches or passes the limit of speed synchronous withthe generator, Mr. Tesla connects up the coils previously short-circuitedwith a source of direct current and by a change of the circuitconnections produces a simple alternation of the poles.Themotor then continues to run in synchronism with the generator.The motor here shown in Fig. 41 is one of the ordinary forms, withfield-cores either laminated orsolid and with a cylindrical laminatedarmature wound, for example, with the coils A B at right angles.The shaft of the armature carries three collecting or contact ringsc D E.(Shown, for better illustration, as of different diameters.)One end of coil A connects to one ring, as c, and one end ofcoil B connects with ring D. The remaining ends are connectedto ring E.Collecting springs or brushes F G H bear upon therings and lead to the contacts of a switch, to be presently described.The field-coils have their terminals in binding-posts KK, and may be either closed upon themselves or connected wr itha source of direct current L, by means of a switch M. The mainor controlling switch has five contacts a b c d e and two levers/g, pivoted and connected by an insulating cross-bar A, so as tomove in parallelism. These levers are connected to the line