| 摘要 |
<p>1,249,247. Tension arrangements. MASCHINENFABRIK RIETER AG. 9 Dec., 1969 [9 Dec., 1968], No. 59930/69. Headings DID and D1J. The tension in a yarn taken at constant speed from an open-end spinning device is controlled by gauging the yarn tension and varying the difference between the take off and winding speed accordingly. As shown, open-end spun yarn 2 is passed over tension sensing arm 4 over fixed guides 5 and 6 and traversed onto the package 8 which is driven by drum 9. The drum 9 is pivotally mounted and rests on a friction driving ring 12 which is axially movably position on drive roll 10. The speed at which the drive roll 10 drives the package drive drum 9 is determined by the axial position of friction ring 12. The position of this ring 12 is varied by the tension sensing arm 4 acting via extension 23 and fork 15. There is a minimum tension variation required before the speed of the drive drum 9 is increased as determined by the distance between extension 23 and the coacting stops 17, 18 on the fork 15. In alternative embodiments, (a) the tension sensing arm is attached directly to the fork 15 (Fig. 4); (b) the sensitivity of a plurality of winding mechanisms is varied from a central point via a rod and springs attached to the forks 15 (Fig. 5); (c) the fork 15 is moved in either sense (so as to move the friction ring 12) by a lead screw device which can be moved to bring it into contact with one of two oppositely rotating rolls (Figs. 6 and 7); (d) when the yarn breaks the extreme movement of the fork can be terminated by a lifting device (Figs. 7 and 9) or a slipping clutch; (e) the yarn tension is varied according to the size of the package with or without other variations being superimposed (Fig. 10); the yarn tension is maintained constant with a decreasing contact pressure of the package on the bobbin as the package grows (Fig. 11). The yarn take off speed can be varied instead of varying the winding speed.</p> |
