Patent GB-787634-A (GB)
Title: Improvements in or relating to knitting and hosiery machines
IPC: D04B9/06
Filed: 1954-03-23
Abstract: 787,634. Knitting-machines. TERROT, H., and KUNEMUND, F., [trading as TERROT SOHNE, S.]. March 23, 1954 [March 23, 1953], No. 8531/54. Class 74 (2). Yarn changing mechanism for a circular machine comprises a yarn gripper 14 for each yarn to be fed, the gripper of a yarn being introduced to the needles simultaneously actuating the gripper of the yarn being withdrawn. Each gripper has means for gripping the yarn which may also include means for severing the yarn or alternatively a separate severing device may be provided which is common to all the yarns. As described in connection with a cylinder-and-dial machine in which three yarns are fed at a feeder, the grippers 14 are pivoted on a lever 15 pivoted at 33 to the casing 32 of the mechanism. The rear ends 141 of the grippers are of arcuate form and are pivoted to links 16 which are also pivoted at 35 to the casing 32 and are also pivotally attached midway their length to members 17 having arms the end of which, under the action pattern control through rods 18, are engaged by cams 4, 5 mounted on the level gearing 3 driving the needle cylinder 1. The front end of each gripper is bifurcated and carries a pivoted plate 20, Fig. 7, provided with a projecting pin 21. The upper edge of the jaw of the plate 20 and the upper arm 142 of the bifurcation co-operate to clamp the corresponding yarn and the lower edge of plate 20, and the lower arm 143 of the bifurcation effects the severing of the yarn. Normally when a yarn is being fed to the needles the grippers are positioned with their operative ends on a raised position two of them each gripping an inoperative yarn whilst the other has the plate 20 open to permit free passage of the yarn being fed. When it is desired to effect a yarn change the pattern mechanism inserts, through a rod 18, the end of the arm of the appropriate member 17 into the path of the cam 4. This cam raises the member 17 and causes the appropriate gripper to pivot so that its end together with its clamped yarn moves around the dial needles to a position beneath these needles whereby its yarn is taken by them. A slight delay is imposed on the movement of the gripper by the cam 4 whilst the yarn is taken by the needles but thereafter further movement by the portion 42 of the cam 4 moves the gripper end downwards and forwards to cause pin 21 to engage a member 22 to open the plate 20 and release the yarn. Simultaneously the upward movement of the member 17 causes the arcuate end 141 of the gripper to engage a spring loaded lever 13 and cause a rocker 11 to engage the pin 21 of the plate 20 of the gripper associated with the yarn to be withdrawn whereby the yarn is clamped and severed. The further downwards movement of the member 17 caused by the cam 5 returns the gripper end to its raised position with the plate 20 open to permit free passage of the yarn, the rocker 11 having been returned to an inoperative position by spring 131. Instead of severing the yarn the gripper end may merely clamp it, a severing device associated with the yam guide plate being actuated simultaneously with the movement of the gripper, this device being common to all yarns.