GB1379531A - Method of and apparatus for stripping a twisted pair of insulated wires - Google Patents

Abstract

1379531 Stripping wires AMP Inc 19 April 1973 [31 May 1972 20 Sept 1972] 18977/73 Heading H2C A method of stripping the insulation from an end portion of a pair of helically-twisted wires comprises clamping the wires a chosen distance back from the portion to be stripped; transversely cutting through the insulation at the stripping position with blades; causing relative rotation between the blades and the clamp to untwist the portions of wires therebetween; and withdrawing the wires while the blades are still closed so as to strip off the insulation forward of the transverse cuts. Apparatus for so preparing a pair of wires comprises a stripping head, 2<SP>1</SP>, Figs. 7 and 9, having a cylindrical body 282 with radial slots 16, 16<SP>1</SP> carrying slidable blade holders 286, 286<SP>1</SP>, captive behind a face plate 284 secured to the rearward face of the body 282. Radical convergence of the blade holders 286, 286<SP>1</SP> causes the blades 308, 308<SP>1</SP> attached thereto to move from an open position through an intermediate position, Fig. 11, whereat they orient the wires, to a closed position, Fig. 9, whereat they cut through the insulation around most of the periphery of the wires without damaging the conductors. Radial slots 285 perpendicular to the slots 16, 16<SP>1</SP> permit the ejection of the severed ends of insulation by centrifugal force at a later stage in the operation. The angle 315, Fig. 11, between the portions 312 and 314 of the blade edge is preferably between 90 degrees and 120 degrees. An angle of 105 degrees is said to be particularly suitable. The stripping head 2<SP>1</SP>, fastened to a rotatable hollow shaft 88, Fig. 7, is actuated by spring- return levers 94, 94<SP>1</SP> engaging pins 30, 30<SP>1</SP> on the blade holders 286, 2861. The levers 94, 94<SP>1</SP> are caused to converge by cam rollers 106 pivoted in a collar 102 axially slidable on the shaft 88 when impelled by an hydraulically-driven clevis lever 108 engaging a peripheral groove 112 in the collar 102. A second hydraulic system 254 then drives a gear train 240, 122, 120 which rotates the shaft 88 together with the stripping head 2<SP>1</SP> sufficiently to untwist the portion of the wires between the stripping head and a cable clamp 82. A stop rod 126 axially adjustable within the hollow shaft 88 determines the length of insulation stripped. In a modification, Fig. 4, the head 2 carries blades 32, 32<SP>1</SP> each having a pair of semicircular edges 46, 48, 46<SP>1</SP>, 48<SP>1</SP> for cutting the insulation after the pins 40, 40<SP>1</SP> attached to the blade holders 18, 18<SP>1</SP> have converged to close the wire orienting members 58, 58<SP>1</SP> pivoted on the face plate 10, into the position shown.