Patent GB-296501-A (GB)
Title: Improvements in and relating to electric oscillation motors
IPC: G04C3/00
Filed: 1927-06-20
Abstract: 296,501. Dehn, F. B., (Losenhausenwerk Dusseldorfer Maschinenbau Akt.-Ges.). June 20, 1927. Alternating-current motors; oscillating machines.-Electrical energy is caused to produce oscillatory rotating motion in a body by means of two magnetic fields which oscillate between two different directions and induce in conductors alternating-currents, the reaction of which with the fields produces oscillating turning moments. The oscillating motor may be connected to its base-plate and its load by resilient members such that two coupled oscillatory systems are obtained with predetermined frequencies and, if desired, with resonance properties between them. An induction type of oscillating motor may be used consisting of a short-circuited winding 3, Fig. 1, rotatable with regard to and inductively coupled to coils 1, 2 having different winding axes and producing an alternating field. One coil may carry continuous-current or both may carry alternating, currents of different phase and the inductance of the winding systems may be compensated by capacity. The argle x o y of magnetic oscillation is preferably from 10 to 30 per cent larger than that of the mechanical oscillation. Fig. 2 shows a form for giving a large amplitude of swing to the core which is fitted with bars A, B - E short-circuited by means of end rings or connected together in pairs A, A<1> - - parallel to a diameter. The stator coils a, b, c, a<1>, b<1>, c<1> and d, e, f, d<1>, e<1>, f<1> are wound either by winding one wire in one pair of slots and then carrying it to the next pair and so on, or by winding one pair of slots full and then passing to the next pair. The second set of coils is wound in the two remaining quadrants thus giving two magnetic axes at right-angles. Alternative dispositions of the coils and armature bars are described in the Specification for giving smaller oscillations. To prevent short-circuit currents from flowing from one armature bar to another on the same group, the arrangement shown in plane-development in Fig. 5 may be used. Here A, B, C and D, E. F are the individual groups of bars of which the middle bars B, E - - are connected to the end rings 5, 6 while the opposite bars of each pair of groups C, D - - are connected together by bars 7, 8. The armature inertia may be reduced by making the laminated iron structure stationary and with openings, Fig. 6, to receive the oocillating system of bars which are carried by endpieces 9<1> mounted on the shaft. Fig. 7 shows diagrammatically the moments of inertia about the vertical axis k<1>, k<2>, k<3> of the base-plate of the motor, the motor and the load respectively, the vertical lines between the hatched areas representing the torsional coupling members between the elements. A load requiring high power through a short distance is shown at 7a and one requiring low power through a large distance at 7<b>. By using coupling members of appropriate resilience the period of the system k<1>-k<2> may be made equal to the periodity of the electromagnetic turning-moments of the motor, or the two systems k<1>-k<2> and k<2>-k<3> may be made to resonate As loads, sifters or oscillating surfaces for producing sound waves may be employed. Specification 19525/04 is referred to.