Patent GB-190227101-A (GB)
Title: Improvements in Boot and Shoe Sewing Machines.
Inventor: URSBRUCK JOHN HENRY
Filed: 1902-12-09
Granted: 1903-03-19
Abstract: 27,101. Ursbruck, J. H., Ursbruck, J. B., Hunter, J. A., and Hunter, M. A. Dec. 9. Leather-sewing machines; Lock-stitch hook sewing- machines.-In the machine shown in Figs. 2 and 3, for sewing boots and shoes, leather, and other heavy materials, the bobbin case 120, Fig. 3, of the under thread is loosely confined between side rings 122 secured together by a screw and thumb nut ; an antifriction roller is arranged in the bottom of the case, and toothed discs on each side at the upper end entering grooves in the conical sides of the case, form loose supports whereby the loop of needle thread has an easy passage over the case as it is drawn over by the oscillating hook 131. The stem 132 of the hook is pivoted on a projecting arm of a rock-shaft 134, Fig. 2, which carries a pinion 135, gearing with a segmental rack 136 at the end of a pivoted lever 137 worked through a link 138 from a cam 14 on the main shaft 2. As the needle loop is drawn out by the barbed needle 18, Fig. 3, the hook 131 is swung forwards on its pivot to catch the thread, which is then drawn over the bobbin case 120. To obtain the swinging movement, the stem 132 of the hook has a pin engaged by an arc-shaped slotted segment 141, Fig. 2, which is worked by toothed lever segments 143, 144, and link 145 from a cam 15. The needle loop is removed from the hook 131, Fig. 3, automatically by the stitch-tightening mechanism. Work - supports; needle - holders; perforating- devices; needle-driving; needle shields.-The work is supported upon a projecting finger 16, Figs. 2, 3, and 8. The curved barbed needle 18, Fig. 8, and curved awl 17 are supported in a vibrating holder 19, which is fitted with a pinion 20, Fig. 3, gearing with a segmental rack 21 on a lever 22, 22<a>, worked from a cam-groove 9 in the cam-disc 3. As the needle and awl pass through the work. they are supported by a grooved roller 23, Fig. 8, above, and a bridge 24 below ; a second support for the side of the needle consists of a pivoted spring-supported finger 25 which is pushed aside by the advancing needle-holder. Feed; presser-feet; presser lifted automatically.- The feed and work-holding finger 28, Fig. 2, is carried on a bar 45 connected by a forked head 42 to a vertically-sliding rod 41. The vertical motion of the finger are obtained from a cam-groove 8, Fig. 3, which acts through an arm 30 and a vertical shaft 31, Fig. 2. Collars 33 on the shaft 31 engage the end of a pivoted lever 34, which connects the shaft 31 and the rod 41. The lever 34 is pivoted upon an eccentric-pin, which can be turned to any position by the handle 38 to vary the distance between the feed-finger and the work-support for different thicknesses of work. The horizontal movement of the finger is obtained from a side cam on the disc 3 which oscillates the shaft 31. The oscillating motion is transmitted through looselykeyed collars 53 on the shaft, each having an arm 54 engaging a tubular sleeve 50 containing a loose block which engages one arm of a pivoted lever 47. The other end of the lever is forked to engage the bar 45 by means of projections 46. The sleeve 50 is connected by an arm 51 with an adjusting handlever 52, by means of which the amount of feed is varied by varying the position of the sleeve 50 on the lever 47 and arms 54. The length of feed may, however, be fixed by fixing the position of the sleeve 50 on the arm 54 ; for this purpose the upper arm 54 passes through a loose block in the sleeve, so that when the nut is screwed up, the loose block draws the arm 54 tight against the top of the aperture through which it passes. The antifriction roller depending from the arm 30 is maintained in contact with the side cam by a spring interposed between the frame of the machine and a lever fixed on the shaft 31, and further, by ribs 62, Fig. 3, which project into a groove in the second antifriction roller through which the upward motion of the shaft 31 is given. Governing needle thread. - The needle thread passes from a spool over a tension disc 65 Fig. 3, the tension being released and applied by the action of wedges on the levers 66, 67, operated by a lever 70 from cams 4, 5 on the disc 3 The thread thence passes over and round the rollers 73, 74, 75, 76, and over the rollers 83 on a swinging let-off and take-up segment 77. The hub of the segment is fitted with a spur-wheel 78, Fig. 2, which gears with a rack 79 on a lever 80 pivoted at 82 and worked from a cam 11. When the rack is raised, an upward swing or thread-pulling movement is given to the segment 77, the backward swing or delivery movement being resisted by a spring 82 at the pivot of the segment lever. The thread passes from the segment 77 to a roller 84, and thence to a roller 85 on the bent of the threadapplying and stitch-pulling arm 86, and through an opening at the end of the arm. A cam 6, acting through a lever arm 90 and a rock-shaft, gives motion to the arm 86 ; the cam 6 is pivoted, and is projected more or less inwards by the arm of an adjustable lever 93 t) vary the stroke of the arm 86. Needles, hook, threading-devices for.-The thread is drawn tight across the end of the arm 86 by a pair of fingers 100, 101, Figs. 3 and 14, so that it may be caught by the barbed end of the needle. As the thread is held by the finger 101 to the right of the arm 86 in Fig. 14, the finger 100 is moved upwards and to the left of the arm 86, and then dropped down behind the thread; it is then moved back to draw the loop, as shown in Fig. 14. The finger 101 then catches the thread, and draws it up over the end of the arm 86. The movements of the finger 100 are obtained from a tappet cam 13, Fig. 3, through levers 102, 103, the lever 102 being pivoted upon the lever 103, which moves in a plane at right angles to that of the lever 102. The arm 111, Fig. 17, carrying the finger 101 slides in a guide 112, and is depressed by an enclosed spring. The guide is attached to a pivoted lever 113, which has a slotted end 114 engaged by a pin on a segment lever 22, Fig. 3. As the lower end of the arm 113, Fig. 17, swings downwards, the block 116, at the top of the guide 112, on coming into contact with the forward end of a lever 112, first raises the arm 111 in the guide 112, and then, as the motion continues, allows it to fall down again behind a bevelled block 119, to carry the hook 101 down behind the loop, as shown in Fig. 14.