GB289054A - - Google Patents

Abstract

289,054. Moneyron, M. April 21, 1927, [Convention date]. Rotary transformers; dynamos, regulating.-A constant-power output transformer for converting polyphase currents into single-phase currents or into polyphase currents for supplying separate apparatus, and especially electric arc devices, consists of primary and secondary windings, such as 2, 3, Fig. 1, the turns of which offer different linking areas to the flux and a damping winding, the main and damping windings being wound on two concentric iron structures relatively rotatable. The rotating member carries the damping winding and may be excited with continuous-current from an outside source 7. Fig. 4 shows the difference in coil areas obtained by prolonging the primary coil 2 beyond one side of the secondary winding 3, both coils being mounted in a. magnetic frame 8 which surrounds an H-shaped twopole rotor 4 having a magnetizing coil and a squirrel-cage winding or copper sheath at. its polar surfaces. The effect under load of the large reluctance of the flux path 17 in the primary side 2 on the smaller-reluctance flux path 16 is explained in the Specification. the result being a practically constant power consumption in the arc. Fig. 7 shows an auto-transformer connection on the three-phase side only. the machine in this case being made with short turns 30, Fig. 8, corresponding with the tapped turns 28 and with long turns 29 corresponding to the other turns of that phase. The primary and secondary windings may occupy the same slots or be arranged in separate slots at. either a common or different raidial depth. To allow variation in the secondary currents, e.g. for fusing electrodes of different sizes, the primary flux may be varied by altering the number of primary turns. Or, as shown in Fig. 13, movable pairs of concentric iron rings 34, 35 and 36, 37 may be traversed axially with regard to the protective ends of the long-turn primary coils. A form is also described in which a single iron ring is moved axially with respect to primary coils which project unilaterally along the machine axis, as shown in Fig. 4. Fig. 16 shows a form in which the secondary windings consist of a fixed part 3 and a movable part 39 in series, the part 39 having the same action on the primary flux as the movable iron rings have. The Specification as open to inspection under Sect. 91 (3) (a) states that the invention comprises also the transformation of single-phase current to single-phase current and that the rotor of the transformer may carry the primary and secondary windings while the stator carries the damping windings in place of the converse arrangement shown. This subject-matter does not appear in the Specification as accepted.