| 摘要 |
<p>1424662 Stranded cables PHILLIPS CABLES Ltd 20 Dec 1972 [21 Dec 1971] 59372/71 Heading B8G [Also in Divisions D1 and H1] A stranded reverse-twist electric cable is formed by feeding wires through separate flexible guide tubes attached to a housing alternately rotated in opposite directions through angles greater than 360 degrees. Electric conductors 17 are fed through flexible, e.g. nylon, tubes 2 which pass through bores 12 in stationary block 11 and bores 10 in block 8 oscillatable and rotatable with housing 3. The twist in the cable may be varied by varying the rate of rotation of housing 3. The tubes are maintained in the blocks by end lips 15, 16 which may be attached to or free to move from the blocks. A core wire 18 may be passed through housing 3. The tubes 2 on bores 10 may be arranged in concentric circles to form a cable having co-axial layers of reverse-twist wires. The reversing twist may be held by passing the wires through a closing die, by sheathing the wires, or by applying a glue such as polybutene to the twisted wires immediately before the reversal of housing 3. Reverse-twist wire sets, simultaneously formed on the apparatus of Fig. 3, and having the same or different twist per unit length, may be advanced through a die former and formed into a bundle having unidirectional or reverse twist. A reverse twist bundle so formed may be successively bound, e.g. with string, taped, e.g. with aluminium, paper or polyethylene tape, and extrusion coated, e.g. with polyethylene. Reverse-twist wire sets, e.g. electrical conductors, each formed in the apparatus of Fig. 3, may be extrusion-coated with an insulating material, bundled together, and the bundle extrusion-coated with insulating material. A reverse-twist set formed on the apparatus of Fig. 3 may be used as a core 18 in similar apparatus.</p> |
