GB1290415A - - Google Patents

Abstract

1290415 Colouring cables STANDARD TELEPHONES & CABLES Ltd 19 Nov 1970 54987/70 Heading D1L A method of colouring plastic insulation provided on an electrical conductor 11, includes the steps of passing a plastic-insulated electrical conductor 11 through a curtain 12 of a polyolefin-based marking ink whilst the plastics insulation is still hot from an insulation extrusion process 10. The curtain of ink 12 is obtained by directing jets of marking ink from at least two ink supply nozzles 7 towards one another such that they collide thus producing the curtain 12. The arrangement comprises a pump 1, an ink reservoir 2 containing a polyolefin based ink, a return funnel 3, and a resilient tube 4, e.g. of silicon rubber, one end of which terminates in two arms 5 and 6, each of which has a jet nozzle 7 provided at its end. The pump 1 is of the peristaltic type in which the ink within the tube 4 is forced along in the tube 4 in the direction shown by the arrows B, under the influence of an external member exerting a periodic unidirectional squeezing effect. The external member may be as shown a rotatable carrier 8 having three rollers 9 mounted on its periphery. When the carrier 8 is rotated, the rollers are caused to roll over the surface of the resilient tube 4 in turn and cause the ink in the tube to move in the direction B.