GB475931A - Improvements in and relating to band resistances for the continuous regulation of heavy currents - Google Patents

Abstract

475,931. Variable resistances. AKT.- GES. BROWN, BOVERI, & CIE. May 25, 1936, No. 14701. Convention date, July 19, 1935. Addition to 467,574. [Class 37] The band resistance claimed in the parent Specification is provided with a contact device which transmits the current from the coil of one resistance to the coil of an adjacent resistance, and which consists of two or more pairs of conducting rollers which are pressed against both faces of both resistance bands in such a manner that at every point the contact pressure is the same. The complete resistance unit comprises four resistance bands a arranged side by side and each consisting of two coaxial and co-planar spirals all the spirals being connected through the contact devices in series. Between the adjacent bands of each pair of coils are disposed the contact devices, all of which are supported by rods z carried by a common shaft, which is rotated to regulate the resistance. Each contact device consists of four conducting rollers 7 which are enlarged at their ends and engage adjacent resistance bands some distance from the edges of the bands. The rollers are journalled in end plates which are attached to transverse members 10, 11 so as to be capable of rocking, and the members 10, 11 are fixed to bridge members 12, 13 pressed together by a single spring o, which distributes the roller pressure equally over the resistance bands.