GB1046130A - Improvements in or relating to potentiometers - Google Patents

Abstract

1,046,130. Potentiometers. WELWYN ELECTRIC Ltd. May 14, 1965, No. 20605/65. Heading H1S. A potentiometer comprises an arcuate strip 2 (Fig. 3) of resistance material, an electrically conducting contact disc 13 arranged at an angle to the resistance strip being caused to make rolling contact with strip 2 by rotation of spindle 8 to move strip 11. The resistance strip may be of carbon or ceramic material. Rotation of disc 13 parallel to the plane of the base is prevented by a projection 22 engaging a slot 23 in disc 13. Alternatively inter-engaging toothed members (Figs. 6 and 7, not shown) may be provided. Two discs 31, 32 (Fig. 4, not shown) may be used and may be carried by a conductive member 33 with a part-spherical tip pivoting in a socket in the terminal pin 21 which is connected to the contact disc or by a hollow member 68 (Fig. 7, not shown) which rests on a coned tip on terminal pin 62. A leaf spring may provide electrical connection and spring biasing between the disc and the carrier member (Fig. 5, not shown). The moving contact member may be of metal or graphite and the rolling contact surface may have a covering of precious metal.