GB653928A - Improvements relating to winding a wire in helical form - Google Patents

Abstract

653,928. Moulding wire-reinforced rubber tubes &c. POBEREJSKY,S. June 23, 1948, No. 16929. Convention date, July 5, 1947. [Class 87 (ii)] [Also in Group XXII] In a machine for helically coiling wire continuously, e.g. in making reinforced rubber tube, brake cable casings with or without plastic coverings, and sheathings, the axial twist produced in the wire by windinghelically on a mandrel is compensated for by rotating the mandrel in the direction opposite to the helixwinding direction once for each turn of the helix. The mandrel 3 has an axial passage 14 leading at the working end to a circumferential helical groove 16, and is rotated in end bearings 4, 5 by gears 6, 7 in synchronism with rolls 11 which feed the wire 12 through a guide die 13 into the passage 14. The grooved part 16 operates in a barrel 2 co-operating in forming the helix 19 which, since the mandrel 3 rotates in the opposite direction at an equal speed, emerges from the barrel 2 without axial rotation. In the form shown a stepped cylinder 20, freely mounted on the mandrel 3, cooperates with a screw-adjustable outer ring 21 to form a nozzle for extruding tube-forming material such as rubber, fed through a throat 26, directly on to the helix 19 as it is formed.