Patent GB-190420475-A (GB)
Title: Improvements in or relating to Sewing Machines.
Inventor: FISCHER GUILLAUME
Filed: 1904-09-22
Granted: 1905-04-20
Abstract: 20,475. Fischer, G. Sept. 30, A.D. 1903, [date appliedfor under Patents Act, A.D. 1901], Strawplait-sewing machines; chain-stitching machines; multiple-needle machines; needle-driving ; needles, hook, threading-devices for ; work-supports.- Relates to a machine for sewing straw braids &c., which forms the stitch between the two layers of the work which are to be united. Two pairs of parallel adjacent needles a, b, c, d are mounted to reciprocate in the same vertical lines. The lefthand needle a of the upper pair and the right-hand needle d of the lower pair are provided with hooks opening backward so as to engage the thread, which is fed between the materials, and pull loops of it out on either side, as shown in Fig. 20. The other needles have hooks opening forward to enable them to carry the thread loops, which are suitably spread, back into the materials, as shown in Fig. 21, prior to the completion of the stitch by a looper acting between the materials in the manner depicted in Fig. 22. Each pair of needle-bars is driven by a double crank engaging the slides 2, so that the needles of each pair reciprocate in opposite periods and the two cranks are arranged to cause needles diagonally opposed to approach the work together. The hooks which spread the thread loops, shown in Fig. 20, comprise two portions e, e', Fig. 10, and are carried by camactuated bars 13. When moved towards the loops, the hooks e engage the forward portions p of the loops and the rear portions q are retained by the hooks e'. As soon as this is done, the inclined surfaces of the hooks engage fixed pins 18 and by them are pressed, against the action of springs 24, into the line of action of the other needles. At the same time, projections also engage pins 22 mounted on revoluble discs, and, as the latter are rotated, other pins 21 press against the arms 23 of the hooks e', thereby separating each pair of hooks e, e<1> and tightening the thread loops between them as shown. The loops, thus tightened, are caught by the needles, the hooks of which open forwards, and are carried through the work. To ensure the engagement of the thread loops, a trigger is advanced at a suitable moment by a cam-actuated rod. The loops are then entered by a cam-actuated hook, which, on its return, carries the rear loop through the other as shown in Fig. 22. This hook and the trigger referred to above are mounted on the centre table which separates the two layers of material, and the hook is guided by pins integral with it, which work in curved slots in the table. To prevent the hook from pushing the thread loops aside, a small stop is mounted in the table underneath the path of the hook and suitably reciprocated by a lever actuated by cam-surfaces on the underside of the hook plate. Presser-feet.-A presser-foot is provided on each side of the centre table, and each is carried by a rod 39. These rods 39 are connected by a spring 48 which keeps their inner ends pressing upon the inclined faces of a bar 49 so that, by the horizontal movement of this bar, caused by the lever 50, the presser-feet may be brought nearer together or be separated. The lower presser-foot is supplied with a head 40 carrying a toothed pinion which gears with a rack at right-angles to the foot, thus allowing the work to be shifted along the surface of the presser-foot freely. The upper presser-foot is provided with a guide 43 mounted in a transverse slide so that, by the movement of a lever 44, it may be moved to or from the front of the machine. The feed-dog i passes through a slot in the lower foot and is mounted on a block 51 so as to be free to move horizontally in a slide, which in turn can move vertically in the machine frame. The vertical motion is supplied positively by an eccentric, and the horizontal motion is obtained from a cam-actuated shaft through a slotted lever. The slide block 51 carries a slotted plate and is connected to the slotted lever by a link. By this device, the feed can be adjusted by altering the relative position of the link by means a suitable lever. Governing needle thread.-The thread is passed between tension discs pressed together by a spring but which are periodically relieved by a cam which engages the end of their spindle.