Patent GB-947116-A (GB)
Title: Improvements in means for and method of operating circular knitting machines
IPC: D04B9/00
Filed: 1961-08-17
Abstract: 947,116. Knitting machines. TEXTILE MACHINE WORKS. Aug. 17, 1961 [Aug. 22, 1960], No. 29724/61. Heading D1C. A multifeed circular knitting machine for making hosiery with turned welts and comprising a rotatable needle cylinder 10 with butted latch needles 16 therein, spaced needle cam sets having opposed stitch drawing surfaces defining in part a normal needle butt path at one of the feeding stations, and means for selecting certain needles to travel the said path, has auxiliary cams located between the said opposed surfaces and movable between inoperative positions and operable positions wherein they define a path of travel for the butts of the non selected needles. The machine described, which is a modification of that disclosed in Specification 790, 141, has four feeding stations A, B, C, D, four cam sets 12, 13, 14 and 15, (see Fig. 1) and incorporates a transfer dial which supports dial bits 20, (Fig. 3), there being half as many bits as there are needles 16. The needle cam set 12 (Fig. 5) has a two part upper cam 25 comprising main and auxiliary parts 26, 27 respectively, the latter being mounted on a spring biased slide 70 and thus movable between inoperative and operative positions by linkage 74 and a cam lug 76 on a pattern drum R. Auxiliary cams 40, 41, 42 located between cam sets 12 and 15 are also displaceable between operative and inoperative positions, the cams 40, 41 being carried on a common spring biased slide 43 movable by linkage 45, 49, 50 under the action of a cam lug 53 on a pattern drum L, the cam 42 being mounted on a slide 60 movable by linkage 63, 64, 65 under the action of a cam lug 66 on the pattern drum R. The dial bits are movable by a bit advancing cam 80 and a bit withdrawing cam 82 (Fig. 8) which cams are themselves moved to operating position by means not described. Sinkers 17 are provided with nebs 30 and platform 31. Operation. The three make up courses are knitted at station A only, cams 40, 41 being in operative position, cams 42, 27 being inoperative. In the first course alternate needles are selected by the jack raising cam to receive the yarn fed. The butts of these selected needles traverse the path N, Fig. 5, while butts of the unselected needles co-operate with the cams 40, 41 to take the path N1 without being raised to take yarn. For the second course all needles are selected by their jacks, their butts all traversing path N, to knit on all needles. The third course is knitted on alternate needles and the movable cam 80, controlling the dial bits 20 moves to advance the bits 20 between the alternate needles after the butts of the intermediate needles move off of the cam 41. The bits 20 are then partly retracted. Yarn is thus fed alternately to the alternate needles and the advanced bits 20 (Fig. 3). The bits 20 are then further, but not fully, retracted and cam 80 is withdrawn. The absence of cam 27 results in the yarn of the loop drawn between dial bit 20 and needle contacting only the platform 31 of the sinker to reduce the strain on the yarn and the transfer elements. The fourth and subsequent courses, to the end of the double welt are knitted with all the needles, and feed stations B, C and D may also feed yarn. For these courses the cam portion 27 is inserted into operative position by the lug 76 on the pattern drum 27, the stitches being then drawn over the nebs 30 of the sinkers in the normal manner. To close the welt the auxiliary cam 42 is moved into operative position by drum R and dial cams 80, 82 also move into position. Alternate needle jacks are again selected to be raised and their butts again follow path N. The butts of unselected needles engage in sequence the cams 40, 41, the latter lowering those needles below the level of the bits 20 which are then advanced by cam 80 to overlie the lowered needles. The latter are then raised by cam 42 to penetrate the bits 20 and the loops held thereby, the dial bits 20 then being immediately withdrawn from the loops by cam 82. Cam 42 continues to raise the intermediate needles to clear both the held and the transferred loops held thereon and both the alternate and intermediate needles take yarn from the feed finger at the station A. All needles then pass down the surface 28 of the cam portion 27 to draw the loops and knit, whereby the make up courses are tied in and the welt closed.