GB833425A - Improvements in or relating to yarn tensioning devices - Google Patents

Abstract

833,425. Knitting-machines. REYMESCOLE, B. T. R. May 3, 1956 [May 5, 1955], No. 13063/55. Class 74 (2). A yarn tensioning device comprises a compensator arm 28, 31 secured to a balance wheel 21 pivotally mounted in a cup 13 containing oil to a level to cover the wheel 21. The spindle 20 of the wheel 21 carries a coil spring 25 which urges the arm 28, 31 to a position in which yarn from a bobbin is guided by eyes 29, 30 into a position on which it makes maximum contact with a cylindrical drag member 18 before passing through a stationary guide eye 33 to the knitting-machine. As the tension of the yarn from the supply bobbin increases or decreases the arm 28, 31 is moved to cause the yarn to decrease or increase its length of contact with the drag member 18 and thereby maintain the tension in the yarn from the device to the machine substantially constant. The position of the guide 33 can be adjusted by moving its supporting bracket 16. The effect of the spring 25 can be varied by moving a clamp 26 securing the end of the spring. In the case of straight-bar knitting machines a spring-loaded arm is provided which engages the yarn extending from the device to the carrier of the machine at the end of each traverse and takes up the slack in the yarn and simultaneously holds the arm 28, 31 in a position which corresponds to the tension in the yarn extending from the device, so that on commencement of the next carrier traverse the yarn does not have an increased tension imposed which otherwise would be caused by the arm 28, 31 taking up the slack and increasing the length of contact of the yarn with the drag member 18. The drag member may be suitably scored to increase the drag effect.