Improvements in electric installations, for illumination circuits

摘要

413,356. Supply and switching systems for lamps; transformers. GUERIN, M., 26, Rue Etex, Paris, and BRETON, P., 21, Grande Rue, Bellevue, Seine-et-Oise, both in France. Jan. 16, 1933, Nos. 1428, 1429, and 1430. Convention dates, Jan. 15, 1932, June 3, 1932, and July 20, 1932. [Classes 38 (ii) and 38 (iv).] Boosting by transformers.-An arrangement for supplying variable A.C. to illuminating circuits comprises a transformer having a rotatable primary winding c<1>, c<2> energized from the supply and a number of secondary windings e connected to the several illumination circuits a<1>, a<2>, a<3>, the primary and secondary being relatively movable into coupling with each other so that the illumination circuits are energized in succession. The primary may be wound on a rotor c and supplied through sliprings f, the rotor being rotated so that the poles thereof come into coupling with the poles of the stator in which the secondary windings e are mounted. The primary and secondary windings may be arranged on U-shaped cores, the horns of which come into magnetic relationship during rotation of the rotor. The pole shoes of the primary and secondary winding poles may be extended so that the total coupling of the primary winding with the secondary windings is maintained constant. In a modification, the secondary windings are wound on cores arranged parallel to the axis of rotation of the rotor on which the primary winding is similarly arranged with shoulder pieces which extend so as to complete the magnetic circuit with the cores of successive secondary windings during rotation. In a further modification the primary and secondary windings are arranged on fixed cores and a rotatable magnetic piece is arranged to couple the primary winding with successive secondary windings. The amount of coupling with the various secondary windings may in each case be adjusted by making the poles of the secondary windings adjustable so as to vary their air gaps, or providing non-magnetic shielding pieces which may be inserted in the air gaps. Where the number of illumination circuits is greater than the number of secondary windings these windings may be connected to a distributer driven in synchronism with the rotating part of the transformer and the illumination circuits connected to or brushes co-operating with slip rings or contacts on the distributer. An additional invariable, but adjustable, voltage may be injected in each output circuit by tapped secondary windings of an auxiliary transformer or the secondary windings of the output circuits may be connected in " star " and the additional voltage inserted in the " neutral " lead. The additional voltage may be taken from a part of the primary of the main transformer or, alternatively, the whole of the primary may be connected in the " neutral " wire of the output circuits in which case the system functions as an auto-transformer with variable coupling between the common primary winding and the several additional windings.