Patent GB-214393-A (GB)
Title: Improvements in installations for operating reciprocating electric motors
IPC: H02P7/00
Filed: 1923-03-05
Abstract: 214,393. Japolsky, N., and Kostenko, M. March 5, 1923. Reciprocating and oscillating machines; brushholders; commutators and collecting-rings; alternating-current commutator machines.-Consists in an electromagnetic installation for operating a reciprocating element comprising an armature which is acted upon by a moving magnetic field produced by a stationary multiphase winding, acceleration being imparted to the moving magnetic field by continuously varying the periodicity of the applied electromotive force. The amplitude of the applied electromotive force may also be varied continuously in order to avoid great changes in the strength of the magnetic field. Fig. 3 shows an installation in which a hammer J is acted upon by a magnetic field produced in the polyphase winding M<1>, M<2>. This winding is supplied from the stator of an alternator G, the rotor R of which is oscillated through a lever K from a rotating shaft W. Further variation in the amplitude of the electromotive force may be effected by a rheostat in the circuit of the rotor exciting winding, actuated by a cam on the shaft W. An arrangement for obtaining variable frequency is shown in Fig. 4. The secondary winding of a stationary phase transformer T is connected to a number of slip-rings R, each of which is connected to a segment of the commutator K. The frequency transformer R, K is driven at varying speeds from a constant-speed shaft D through a roller rand cam F, and polvphase current of varying frequency is led off by the stationary brushes B". In an alternative method of imparting a varying speed to the frequency transformer, a differential gear may be interposed between it and the driving member, for example, the alternator supplying the current, and the intermediate wheel of the differential gear is caused to rotate at varying speeds by means of cam and roller mechanism. If it be required to vary the amplitude of the applied voltage as well as the frequency, two frequency transformers K<1>, K". Fig. 8, may be connected to the windings M of the reciprocating machine. The transformers R<1>, K<1> and R<11>, K<11>, Fig. 10, may be driven at different varying speeds from the alternator S G through differential gears L<1>, L0<SP>1>, L2<SP>1> and L0<SP>11>, L2<SP>11>, the cams F<1>, F" being designed to give the intermediate wheels L0<SP>1>, L0<SP>11> the required varying speeds. In an alternative arrangement for obtaining a voltage of varying amplitude and periodicity, a constant-speed armature R, Fig. 11, has two commutators K<1>, K<11>, each commutator having a set of brushes B1<SP>1>, B1<SP>11> which are rotated at varying speeds by cams F<1>, F<11>. Current is led off to the reciprocating machine through slip-rings and fixed brushes B11<SP>1>, B11<SP>13>. The brushes B1<SP>1> B1<SP>11> may be rotated by electrical means, such as a disc of copper supplied with continuous-current and revolving in a magnetic field. For high-power installations, current may be supplied from a commutator generator cf the type described in Specification 210,482. The exciting winding 1R - - 6R on the rotor of the commutator-generator K, Fig. 15, is fed with alternating current of varying periodicity from a separate exciter, and the phases 1M - - 6M of the reciprocating machine are connected to the stator windings Is - - 6s.