Patent GB-682774-A (GB)
Title: Knitting machine
IPC: D04B9/10
Filed: 1949-09-08
Abstract: 682,774. Knitting-machines. SCOTT & WILLIAMS, Inc. Sept. 8, 1949. [Dec. 30, 1948] No. 23316/49. Class 74 (ii). A superposed cylinder machine is provided with wrap yarn fingers and needle selecting mechanism such that one or two selections of a group of needles in the lower cylinder may be made'during each course of knitting, a separate wrap yarn being fed to the needles of each selection. The wrap yarn fingers 64, 641 are mounted in pairs, or if desired a dummy finger may be associated with an operative finger, and they extend within the upper cylinder to project between the upper and lower cylinders. Each finger of a pair is apertured as at 91 and a loose pivot extends therethrough, the movement of one finger thereby being limited by the movement of the other. The upper ends of the fingers are operated by jacks 72, having frangible butts 73 which engage cams to project the finger across the needle circle. These cams are operated by Bowden wires from the pattern drum of the machine. Butts 84 are provided on the fingers and are engaged by cams 260, 262, 264 to ensure positive return of the fingers after they have passed the selected needles. Spring loaded cams 272 engage the fingers as they are urged outwardly by their jacks and keeps them under control during their outward movement. By suitable selection of the butts 73 on the jacks 72 and of the butts 84 on the fingers, and by so positioning their operating cams, during needle selection first one finger can be projected across the needle circle, whereby it is held by a resilient abutment on the lower cylinder to enable the needles to pass, and then withdrawn, and then the second finger can be similarly operated. Needle selection is achieved by selector mechanism comprising two trick wheels 300, 308 which are rotated through common linkage operated by a cam 278 on the upper cylinder, so that their tricks engage back of levers 432, 388. These levers engage slides of two separate banks of slides 438, 398 which operate on the butts of the sliders engaging the needles in the tricks of the lower cylinder. During wrapping, therefore, the needles are selected by the first bank of slides acting on the butts of the sliders whereupon the selected needles receive a wrap yarn, these needles then being lowered and a second selection of needles by the second bank of slides being made. For the purpose of making selection of the needles the sliders of the lower cylinder are provided with frangible butts. The wrap yarns are fed over a wrap horn 188 which is provided on the lower end of a stationary tube extending within the upper cylinder. The wrap horn is raised towards its end to ensure correct positioning of the wrap yarn when the needles are raised after wrapping. To enable a greater selection of needles to be achieved, each trick wheel is adapted to be raised or lowered vertically by mounting it on a support resting on an arm provided with stepped surfaces. The arm is movable by means of a Bowden wire operated from the pattern drum to bring the stepped surfaces into contact with the support. Additional selecting mechanism is also provided by means of levers 452, 458 operated from the pattern drum and having teeth 454, 462 which bear on the bank of levers 442. By selecting appropriate teeth on the levers 452, 458 they may operate to withdraw the corresponding slides from action on the butts of the sliders. A lever 422 is also provided for withdrawing the bank of levers 388. To ensure correct radial alignment of the slider butts with the slide, a cam surface 418, 448 is positioned adjacent the leading edge of each bank of slides to guide the butts, the cam surface being on the end of an arm resiliently urged towards the needle cylinder and which is engaged by a lever 442, 406 lying along the top of the levers 432, 388. This lever is adapted to withdraw the cam surfaces from their operative positions when the slides are withdrawn by means of an abutment provided on the levers 458, 422. The machine is also provided with a hand operated arrangement which by operating on the Bowden wires controlling the wrap finger cams and needle selecting mechanism withdraws them all from operation. A slider stop motion arrangement in the form of an abutment which engages a slider which has failed to be lowered by the stitch cam is attached to the machine as well as a needle leveller and a latch opener. The lower ends of the walls of the needle tricks of the upper cylinder are constituted by movable members. Specifications 526,963 and 594,903 are referred to.