GB1360883A - Method and apparatus for producing textured yarn - Google Patents

Abstract

1360883 Friction twisted yarn CHADBOURN Inc 9 May 1972 [8 Dec 1971] 21586/ 72 Headings DID and D1F A method of producing textured yarn on a draw-twister comprises moving the yarn along an elongated feed path and heating the yarn while in motion along the length of the path, cooling the yarn as it moves from the heating zone, then drawing the yarn across a friction surface on a freely rotatable roller the axis of which is at an acute angle to the yarn approach and causing the moving yarn to move the friction surface to twist the yarn which twist backs into the heating zone, and drawing the yarn from the friction surface along a loop path on a smaller diameter portion of the said roll, the loop path being in a plane perpendicular to the axis of rotation of the roll. The yarn 1 taken from a supply passes round feed roll 2 of the draw-twister and then passes through a heating zone 8 including a tubular heater 15, the yarn passing over the surface thereof. The direction of the yarn is changed by rolls 9 and the yarn passes through a cooling zone before contacting the friction surface of freely rotatable roll 12. The twisted yarn then passes round draw roll 5 and the drawn, textured yarn is taken-up. The roll 12 is in the form of a V-grooved or modified V- grooved roll, the yarn being first brought into contact with one side of the groove surface, then down into the bottom of the groove and then up the opposite side of the groove, while being kept in contact with the friction surface. The grooved roll may be made of metal or plastics material, polyurethane being most preferred. The groove may be in the form of a straight sided V, a concave, or convex sided V, one side of the V may be longer than the other, or in a further embodiment, the groove has a flat bottom with the sides extending perpendicularly to bottom, the outer edge of each side being convex. As the yarn moves down the groove and then up again, a decreasing and then increasing number of turns per inch is imparted to the yarn. The yarn is shown as contacting the roll 12 through 360‹, but this is not essential.