GB235296A - Improvements in inductance coils and in the method of producing the same - Google Patents

Abstract

235,296. Snowball, J. G. March 11, 1924. Inductances.-An inductance coil, variometer, or vario-coup'er has its edges bound together with cotton, twine, &c., in order to avoid the use of wax &c. for stiffening the coil. Fig. 2 shows a coil wound on a cardboard or like sleeve d which is slipped over a central boss on a former. The boss projects from a base, from which also projects a concentric row of pins. The coil is then wound so that each turn is substantially in the form of a triangle passing round two pins at two of its corners, the sides of the triangle being substantially tangential to the sleeve d, while the third corner of the triangle is in close proximity to the sleeve. The winding passes over pins at the points 1, 17, 18, 34, 35, 6, 7, 23, 24, 40 and so on. Owing to the number of crossing points at the inner periphery of the coil, a triangular cross section is produced. The corners e are bound with cotton, twine, &c. More than two pins may be passed over at a time. A hemispherical coil may be made by employing a dome-shaped former f, Fig. 4, having at its top a cylindrical projection f<1> and a number of radial projecting pins g, the method of winding being similar to that shown in Fig. 2. These hemispherical coils may be connected together in pairs to form the rotor and stator of a variometer or vario-coupler.