GB590560A - Improvements in or relating to variable resistance devices - Google Patents

Abstract

590,560. Regulating switches. WEST & CO., Ltd., A., and COUPAR, J. Oct. 7, 1944, No. 19271. [Class 38 (v)] In a variable resistance comprising two series of stationary contacts 1 connected to tapping points of two separate resistances and mounted in a circular manner around a bridging member, both series being co-axial and located in parallel planes ; the bridge member consists of a non-rotating co-axial insulating disc 3 carrying a contact ring 2, or alternatively separate contact members, on the outer edge, which engage the fixed contacts 1 at diametrically opposite points. The ring is mounted in a tilted position and contact is made from one fixed contact to the next by varying the plane of tilt of the contact bridge. A spindle 7 driven by worm gearing 9 and 10 has fitted to it a spider 6 which is tilted. Rollers 5 on the spider engage on the inside edge of the bridge member which is prevented from rotating by the roller 11 which engages a stop 11<1>. Each series of fixed contacts may extend for rather less than 180 degrees or alternatively may extend along the path of almost a complete circle.