GB252496A - Improvements relating to electrical resistances - Google Patents

Abstract

252,496. Lloyd, S. C., Harlow, P. L., and Metropolitan-Vickers Electrical Co., Ltd. March 24, 1925. Wire and ribbon resistances, cored.-A resistance is wound on a grooved core divided longitudinally, the two halves being moved relatively to each other after winding so as to join the coils and secure them in place. The coils are preferably of elongated or elliptical shape so that the greater part of them is spaced from the core. In the form shown in Figs. 1 and 3 the core is solid and a number of units are threaded on bolts 8, slots 6 being provided bv which the halves 2, 3 of the cores can be slid longitudinally on each other after the coils 1 have been wound on them. The cores are so constructed that when they are assembled as shown in Fig. 3 the ribs on one core project into the grooves on the next. Instead of sliding longitudinally the halves of the cores may be pivoted together and turned into positions. The cores may also be made from sheet metal blanks shaped as shown in Fig. 7, the tongues 10 and 11 being bent up as shown in Fig. 5 and the whole covered with insulating material 14 as shown in Fig. 4. In a further modification the cores may be made from metal channels, corrugated and covered with insulating materials.