GB815785A - Improvements in flexible force-transmitting cables - Google Patents

Abstract

815,785. Flexible power transmission members. TELEFLEX Inc. Nov. 18, 1955 [Nov. 18, 1954], No. 33096/55. Classes 80 (1), 80 (2) and 80 (3). A flexible cable capable of transmitting substantial rotary forces comprises a base wire or wires and two or more successive lays of wires wrapped helically on the base, each lay comprising two or more solid wires, the outermost lay having more wires than the innermost lay, all the wires being of equal diameter, the pitch in each lay being only slightly greater than the sum of the diameters of the wires making up that lay, and alternate lays being wrapped in opposite directions. As shown in Fig. 1 a cable comprises a core 16 wrapped with a lay 18 of four wires, a lay 20 of six wires and a lay 22 of six wires. A helix wire 26 of hand opposite to that of the lay 22 and with open turns is wrapped over the lay 22, and a sheath comprising a closely-coiled single wire in which the cable is slidable and rotatable may be applied over the helix wire 26. The sheath may be interrupted for engagement of a member such as a worm-wheel with the helix wire. In a second embodiment the helix wire is of trapezoidal section with slightly concave sides to provide lubricant reservoirs and the sheath wire is preferably flat.