GB892912A - Improvements in or relating to yarn tension control devices - Google Patents

Abstract

892,912. Yarn trimming. STANIER, H. Jan. 1, 1960 [Oct. 2, 1958], No. 31440/58. Classes 120(2) and 142(1) A yarn tension control device comprises a disc tension means followed, with respect to the direction of the yarn travel, by a yarn trapping means which normally provides a free passage for the yarn but traps the yarn when the tension is relieved, and means for changing the position of the disc tension means so that the path and therefore the tension of the yarn may be varied. As shown in Fig. 1 the base plate 11 of the device is fixed in a horizontal plane to a side member 13 of the creel and carries a ceramic guide 14 in the centre of an anti-ballooning disc 12 at a suitable ballooning distance from the package 50. The yarn is withdrawn over the end of the package, passes through the trapping means 28 and through a movable guide 20 intermediate fixed guides 18, 19. Guide 20 rotates about a pivot 23 (Fig. 3) in a stiff wire arm 21 under the influence of a counterweight 22 so arranged that the guide tends to pull the yarn out of a straight line path between guides 18 and 19. When the yarn runs in a straight line path from 18 to 19 the counterweight acting as a cam raises a plunger 26 which lifts the upper disc 32 of the trapping means so that the yarn is unimpeded. The trapping means comprise a fixed post 27 carrying lower and upper discs 30, 32 which are freely rotatable, the upper disc being adapted to be lifted as described above; a screw provides means for varying the instant at which the upper disc is raised. Between the guide 14 and the trapping means the four similar disc tensioners are adjustably mounted in slots 36 and 47. Each device (Fig. 5) comprises a guide post 40 which has upper and lower, freely rotatable discs 41, 42 and is adjustably fixed to the base 11 by a bolt 39 engaging a nut 38. The yarn is arranged to pass through or about one or more of the tensioners 41, 44, 48, 49 in any desired path to give the required tension; further adjustment in the yarn may be obtained by altering the positions of the tensioners, by altering the upper discs for discs of different weight or by placing two or more upper discs on the tensioner. When the yarn slackens, e.g. when a package empties, the guide 20 falls away and the counterweight 25 engages an electrical contact so as to make, or break, a circuit which in turn stops the machine to which the yarn is passing; at the same time the device 28 traps the yarn which is thus held taut between the using machine and the device. The device is threaded by a needle or hook, the tensioner 41 having been shifted to either end of its slot. Since the discs in the tensioners and trapping means are freely rotatable they are self cleaning. Specifications 795,800 and 820,481 are referred to.