Patent GB-994521-A (GB)
Title: Improvements in or relating to straight bar knitting machines
Inventor: HARRISON MICHAEL
IPC: D04B11/00
Filed: 1960-06-14
Abstract: 994,521. Knitting. WILLIAM COTTON Ltd. June 13,1961 [June 14,19601,No.20778/60. Headings D1C and D1K. The machine described in Specification 930,068 is modified so as to produce a fabric having a cable stitch arrangement in which the wale on either side of the cable stitch pattern is composed of drop stitches. For this purpose a cable stitch box 40 is provided in a straight-bar machine for each cable stitch pattern it is desired to produce and one series of boxes is mounte on a bar 38 capable of being shogged longitudinally in both directions. A second bar 39 is provided for a second series of cable stitch boxes. The whole mechanism for supporting the boxes 40 is capable of being raised and lowered by the normal narrowing machine mechanism but additional mechanism is provided for raising the drop stitch points 47P, 48P and the cable stitch points 42P,43P in each of the boxes 40 out of operation and in addition each box 40 can be moved manually into its operative position in which it backs against the narrowing point bars 30... 33 to position its points above the needles. The cable stitch points 42P,43P are mounted in fingers 42,43 capable of simultaneous and also independent movement by a rod 45 operated from the main cam-shaft. On either side of the points 42P, 43P is mounted a drop stitch point 47P, 48P carried by slides 47,48 operated by a rod 46 from the main cam-shaft. Prior to the commencement of the cable stitch pattern it is necessary to transfer the loop of each of the wales on either side of those containing the pattern to enable drop stitches to occur in these side wales without the previous loops unravelling. For this purpose, initially the drop stitch points 47P, 48P are retained in a raised position in the bore 40 and both sets of points 42p,43p are in a low operative position. A fashioning motion is then imparted to the box 40 such that the points take the loops from the corresponding needles and transfer them one needle to the right as shown in Fig. 15. The shogging motions for the points is obtained from a pair of Dawson wheels 64, 65 for those boxes 40 coupled to the bar 38 and Dawson wheels 67,68 for those boxes coupled to the bar 39. The points are then raised and shogged a further needle space to the right whereafter they are lowered and pick up the loops on the corresponding needles and transfer them one needle to the left as shown in Fig. 21. This leaves two side needles 1b, 1c devoid of loops, the loops from these needles having been transferred inwardly to the adjacent needles and consequently the wales formed by the needles 1b 1c are prevented from running. During the knitting of the next and subsequent courses the needles 1b 1c are caused to press early by the drop stitch points 47P,48P, which have been lowered, engaging these needles such that the needles cast off the yarn without knitting it and a drop stitch formation D, D1 is provided in the corresponding wales, Fig. 27. When the cable stitch formation is to be effected the drop stitch points 47P,48P are raised and the transfer points 42P 43P lowered to engage the corresponding needle loops and transfer them three needles to the right as shown in Fig. 30. The transfer points 42P are then raised to an inoperative position and a second motion imparted to the box 40 which results in the points 43P retaining their loops and a shogging motion equivalent to six needle spacings is imparted to the box 40 to cause the points 43P to transfer their loops to the same needles which had their loops removed by the points 42P. The cross over effect as shown in Fig. 36 is thereby achieved and is further enhanced by the drop stitch effect on either side of the cable stitch pattern.