Patent GB-351480-A (GB)
Title: Improvements in or relating to multicore electric cables
IPC: H01B13/02
Filed: 1930-03-22
Abstract: 351,480. Making electric cables. BLOOMFIELD, C.W., 190, London Road, Hackbridge, Surrey. March 22, 1930, No.9245. [Classes 83 (ii) and 83 (iv).] ] Power hammers. -The segmental cross section and spiral lay is imparted to a stranded conductor for a multicore cable by passing the unshaped conductor between swages or hammers having suitably formed faces and causing either the conductor or the hammers to rotate about the longitudinal axis of the conductor whilst it is being passed between the hammers. A machine for shaping and spiralling a conductor 22 comprises a standard 1, Figs. 1 and 2, in which is journalled a member 3 carrying a pneumatic hammer 4 and adapted to be rotated by a chain 19 and sprocket wheel 20 secured to the rear end of the hollow journal 2 of the member 3. A guide 7 mounted on the member 3 is formed with grooves to receive a fixed swage 8 and a reciprocating swage 9 attached to the ram 10 of the hammer 4. The conductor 22 under treatment is passed through the hollow journal 2 of the member 3 and between the rotating swages 8, 9 which impart to the conductor the desired shape and spiral twist. The pitch of the spiral twist may be varied by altering the speed at which the conductor is drawn through the swages orby varying the angular velocity of the member 3. In order to prevent rotation of the conductor as it is drawn between the swages, a die 23 having the shape of the finished conductor is mounted beyond the swages in brackets 24 carried on the member 3. Air for operating the hammer 4 is supplied through a pipe 12 to a circumferential channel 13 formed on the inner face of a member 14 surrounding a conical portion of the member 3 and retained in position by pins 15 and springs 16 carried by the frame 1. The circumferential channel 13 communicates with the hammer 4 through a duct 17 formed in the member 3 and a flexible pipe 18 connected thereto. The member 3 may be provided with a balance weight 25. Fig. 3 shows apparatus for shaping and spiralling a continuous length of conductor. The conductor 22 to be treated is coiled on a drum 26 and passes through a centring guide 28 to a swaging machine of the type shown in Figs. 1 and 2, through which the conductor is drawn by a pull-off device 29 to be coiled on a receiving drum 30. Fig. 4 shows an arrangement wherein the conductor is rotated about its axis as it is drawn through non-rotary swages. The conductor 22 to be treated is wound on a drum 32 journalled in a flyer 33 which is adapted to be rotated in standards 34 by a chain or belt drive 36 from a shaft 35. The conductor from the drum 32 passes through the hollow journal 38 of the flyer 33 to guide pulleys 39 mounted on a standard 40 which carries the swages 8, 9 operated by a pneumatic hammer 4. After being drawn between Tire-swages, the conductor passes through the hollow journal 47 of a flyer 44 to a pull-off device 45 and thence to a take-off drum 46. The pull-off device 45 and the take-off drum 46 are mounted in the flyer 44 which is rotated at the same speed as the flyer 33 by a belt or chain drive 54 from the shaft 35. The pull-off device 45 is driven by a worm 49 on a shaft 50 having a gear wheel 51 which meshes with a fixed wheel 52 mounted on the standard 43 of the flyer 44. The take-off drum 46, which may be provided with a device for laying- off the conductor as it is coiled thereon, may be driven by a belt or chain 53 from the pull-off device incorporated with a slipping arrangement to compensate for variation in the diameter of the coiled conductor as it is wound on the drum. In order to centralize the conductor as it passes through the swages 8, 9, a guide 41, rotatably mounted in a bracket 42 on the standard 43, may be disposed between the swages and the hollow journal 47 of the flyer 44. The hammers for operating the swages may be actuated electrically or mechanically by means of cams, and a plurality of co-operating swages may be employed. Specification 11929/14, [Class 36, Electricity, Conducting &c. ], is referred to.