GB687289A - Improvements in or relating to stranding machines - Google Patents

Abstract

687,289. Wire stranding machines. BRITISH INSULATED CALLENDER'S CABLES, Ltd. April 19, 1951 [April 20, 1950], No. 9753/50. Class 109 A machine for stranding together a number of wires to form an electric conductor or a wire rope comprises at least one section which comprises axially aligned front and rear groups of axially aligned bobbins, means for drawing off wires from the front and rear groups of bobbins alternately and guiding them towards a lay plate, and means for driving each group of bobbins independently of the other group for the purpose of re-winding the bobbins of one group whilst wires are being drawn off the bobbins of the other group. A stranding machine may comprise six such sections wherein the wires from section I are twisted about a central core in the first lay plate 11, those from sections II and III being twisted about the first layer in a second lay plate 11, and a third layer being added to the rope in the third lay plate 11 from sections IV, V and VI, a rope of thirty-seven wires thus being formed with six wires in the first layer, twelve in the second and eighteen in the third about the central wire. The groups are driven from a motor 8 through lay shafts 5, 6 and 7 respectively and the machine also comprises two pre-spiralling heads 12, a capstan 9 and a take up reel 10 all driven from the motor 8. Each section comprises two axially aligned units of axially aligned bobbins 23 and 24 mounted on tubes 21 and 22 respectively with which they may be constrained to rotate through a friction clutch mechanism. Each of tubes 21 and 22 are rotatably mounted on and may be constrained to rotate with, the central tube 1 by means of a dog clutch. A flyer comprising end supporting plates 43 and a central plate 28 is mounted on the tube 1, and also comprises arms 27 upon which are mounted pulleys 30 for guiding the wires 26 to pulleys 31 and 32 and thence through guide tubes 41, Fig. 3 to the lay plate 11. The arms 27 are mounted in bearings 33 and 34, and 36 and 37. In operation, only one set of arms may be used, viz. when winding the wires from bobbins 23, the arms occupy the position shown in full lines in Fig. 2. By disengaging the tube 22 from its dog clutch the bobbin unit 24 can be rotated independently of the central tube 1 and the bobbins replenished with wire from swifts 53 (Fig. 1). When the wire on the bobbin unit 23 is exhausted the section is stopped, arms 27 transferred to the position shown in broken lines in Fig. 2, and the tube 21 disengaged from its dog clutch. Thus when the machine is restarted the wires are drawn from the bobbins 24 and the bobbins 23 are refurnished with wire, a chain drive 49 being provided on each unit for this purpose. The central plate 28 may serve as a brake drum 38 for a central band brake 39 operated by an electric thruster 40. The friction clutch mechanism for each bobbin unit comprises axially movable friction couplings 25 placed between the bobbins, an axially adjustable collar 43 carrying a friction disc on its side facing the end bobbin, and a sliding collar 44 also carrying a friction disc. Pressure is applied to the collar 44 through thrust pins 46 from a split disc 45, the halves of which are spring urged toward each other to create pressure on the oblique faces 56. The pressure diminishes with increase of speed due to centrifugal force.