GB241383A - Improvements in and relating to electric inductance coils - Google Patents

Abstract

241,383. Macadie, D. Oct. 16, 1924. Inductances.-An inductance coil has each layer supported by wedge-shaped spacers a<1> so that the layers b - - b<4> are alternately conical and cylindrical, thereby causing turns between which the potential difference is greatest to be spaced further apart than those between which there is a less potential difference. The spacers a<1>, of which there are preferably eight to each layer of the winding. are fitted at their ends in radial grooves in a casing c and cover-plate d, the innermost set resting on a tubular core a or cardboard, ebonite, &c. A further groove is formed in the cover d to take the lead from the inner end of the coil. Alternatively a former may be provided with grooved cheeks, between which the series of spacers are slipped. After winding, an insulating strip of mica, celluloid, &c. may be fastened round the coil between the side cheeks. The winding may be of insulated wire, or of bare wire with spaced turns, or of two or more wires twisted together. The angle between successive layers may be different. According to the Provisional Specification, the spacing-pieces may be made parallel throughout and have slots, cut at varying depths to take the windings; also more than one layer may be wound over each set of spacers, and each set of wedges may be replaced by a circular wedgeshaped spacing-piece.