Patent GB-613838-A (GB)
Title: Improvements in or relating to circular independent needle knitting machines
IPC: D04B15/08
Filed: 1945-10-17
Abstract: 613,838. Knitting. HEMPHILL CO. Oct. 17, 1945, No. 27170. Convention date, Oct. 18, 1944. [Class 74(ii)] A superposed, axially aligned, rotatable cylinder machine employing double ended latch needles and sliders in both cylinders for engagement with the needle hooks to cause lower cylinder sliders, the length and shape of the engaging ends of which are such that when a slider is coupled to a needle hook the tip of the latch is exposed and forms one side of a space between it and the slider end; and a needle divider for entering the space to disengage the sliders from the hooks, the divider being positioned with respect to the lower hooks of the needles, when in operative position, to hold their latches open. The needles 4 are selectively operated in either cylinder by sliders 5 or 6, having operating butts 7, 8; whilst, for transfer of needles from one cylinder to the other and selection of needles for other purposes such as wrapping, there are provided upper cylinder controlling jacks 10, having operating butts 12, and lower cylinder controlling jacks 9 having operating butts 11 and selecting butts 13 (which latter may be frangible butts of Specification 370,023). A sinker head assembly surrounds the lower cylinder and may incorporate a cam cap similar to that described in Specifications 586,770 and 600,947, to enable the knitting of the plain fabric of a stocking leg and foot, except heel and toe, by the method in which the yarn is drawn over the backs of the sinker instead of in their throats. Needle transferring; latch opening and closing.-To transfer needles from upper to lower cylinder, a cam 45 is moved in to engage butts 12, so projecting the sliders and needles. The ends 21 of the sliders 6 pass over a relatively thin point in a lip 51 of a needle divider 49 (which is moved into operative position when rib knitting is to be done) and through an opening 50 therein. The lip, the cross-section of which progressively increases from this point, acts as a cam and disengages slider hooks 22 from the needle hooks; at the same time, the lower hooks of the needles have snapped into engagement with the hooks of the sliders 5. The upper cylinder jacks and sliders are thereupon raised to a high position. To transfer needles from the lower to the upper cylinder, the associated jacks 9 are raised by a cam 63. The ends 21 of the sliders 5 are so short that the tips of the lower latches of the needles are exposed. A thin part 65 of the lower edge of the needle divider can, therefore, enters between the latches and the sliders; and, since the edge progressively increases in thickness from this point, the sliders 5 are disengaged from the needles. The hooks of the upper sliders 6 engage with the upper hooks of these needles and the lower cylinder sliders move down again. The divider 49 acts as a guide, to support a needle whilst it is being uncoupled from a slider. When the divider 49 is moved in, the yarn finger 74, Fig. 41, is moved to a lower position, to ensure that the yarn will be fed within the latches of the upper cylinder needles; a horn 73 on the divider deflects the yarn downwardly and outwardly and also delays the closing of the needle latches. A ring-like latch guard 67, Fig. 20, keeps closed the latches of the upper cylinder needles except whilst they are passing the divider 49 (and for a short distance on each side thereof, so that they may be opened by the loops as they pass on to the shanks and be closed by them as they are cast off). The inner surface of the guard 67 is broken by an offset part 68 above the divider 49 and is there replaced by two or more springs 69 which control the latches, but will yield outwardly to permit the disengagement of the sliders from the needles. An inwardly projecting part 70 of the guard ensures that, as the needles move down, their latches are completely open and cannot strike the top of the divider 49. Each of the ends 71, 72 of the offset part 68 is bevelled in both directions, so that any partly open latch will be either opened or closed. An auxiliary fabric take-up device, Fig. 29, is provided to ensure that the fabric immediately succeeding a heel or toe pocket shall be properly tensioned. This comprises a ring 88 having inwardly projecting points 89, and a disc-like pocket spreader 81 having V-shaped recesses adapted to register with the points 89. The disc and ring rotate together with the cylinders but may have relative vertical movement. When a pocket 96 is completed, the spreader 81 is lowered against spring action, to engage with it and spread it, and the ring 88 is moved up from a low position and passes along the outside of the pocket, the points 89 penetrating the fabric thereof. The spreader is then allowed to rise and the ring assembly to descend by its own weight, supplemented by a spring, if desired. The rest of the fabric, meanwhile, passes through an arcuate slit 97 and is tensioned by the regular fabric take-up. When the supplementary take-up has reached a low position, it is released, the tension then being maintained by the regular take-up. Wrapping mechanism.-Co-axial wrap shafts 83, 84, Fig. 3, carying wrap heads 108, 109, can be stopped relatively to each other by a vertically movable pin engaging helical slots of opposite hand, formed in the shafts. The shafts are driven with the cylinders, through gears 114, 115, 116, 117, Fig. 11, and are moved to and from an operative eccentric position by swing- ing them around the gear 116, the gear 117 being rotatably and swingably supported by a plate 122 integral with or attached to a hub 118 and resting in an arcuate guide 123 having a screw at each end to adjust the extreme positions of the swing. The plate 122 supports the entire wrap mechanism and also the heel and toe pocket spreader. A wrap horn is supported on a rod 129 and can be lowered and raised to and from its operative position by suitable mechanism acting on the end of a shaft 131. The wrap heads may have the yarn guides 139, Fig. 38, carried on frangible tongues 140: for example, breaking out all but a few at opposite sides of each head, the heads can be kept in position for making wrap patterns in the non- rib side panels of a stocking without interfering with the needles when they operate in both cylinders to form the true rib parts. Colour-within-colour wrapping may be performed by using a head such as 141, Fig. 36, having long and short yarn tubes 142, 143. Plating.-Two yarns may be fed from yarn lever 74, Fig. 41, or from separate yarn levers. For reverse plating, the machine may be provided with the 12 step reverse plating equipment of Specification 344,486; see also Fig. 31 (not shown). Stockings.-Each completed stocking is followed by several courses of loopers rounds 16, Fig. 2, which may be followed by one or more tuck courses 17, to provide a ravel-resistant section at the 'end of the knitting. During the knitting of the last course 18, the loops on the lower cylinder needles are run off, the upper cylinder needle loops 19 providing a clearly seen severing course. The tuck courses enable the take-up tension to be maintained through the loops 19. Courses 20 to 26, repeated, as in Fig. 2, provide the welt. The stocking of Fig. 32 may have normally plated rib areas, such as 103, 104, 105 in top, leg and foot, and reverse plated diamonds 106 with reverse spiral wrap 107 outlining the diamonds. The elastic top of Specification 548,951 may be made, using the lower cylinder only. Specifications 344,486, 512,539, 536,948, 613,897, 613,898, 613,899, 613,903, also are referred to.