Patent GB-191119679-A (GB)
Title: Improvements in or relating to Sewing or other Machines applicable for use in connection with the Manufacture of Boots and Shoes.
Inventor: BOULT ALFRED JULIUS
IPC: D05B81/00
Filed: 1911-09-04
Granted: 1912-10-04
Abstract: 19,679. Boult, A. J., [United Shoe Machinery Co.]. Sept. 4. Boot-sole sewing machines; stopping-gear, non- automatic; welt-cutting and end-holding; weltmeasuring.-In shoe-sewing and other machines for attaching to stock a welt or strip of material, power-actuated welt end-holding and severing mechanism is provided, adapted, in conjunction with a welt-measuring device, to operate automatically when the welt is pulled by the operator on removing the shoe at the end of the sewing operation. In the shoe-sewing machine described, the cam-shaft 6 is driven during the sewing operation by a pulley 7, but, on stopping, it is driven slowly backwards to the stop position by a continuously-running wormwheel 19 through a clutch 18, 18<1>, as described in Specification 5453/12. The welt end-holding device comprises a jaw 54, Fig. 10, slidably mounted in a bar 58, and a jaw 55 pivoted on an eccentric adjusting-stud 63 carried by the upper jaw. The severing-knife 56 is mounted on a slide 64 which has a cam-surface 65 adapted to engage the inner end of the jaw 55. The slides have rack teeth 57, 64, Fig. 7, and are driven by pinions 66, 67 on a shaft 59 which is driven by a gear segment 68 secured to a rockshaft 69. The shaft 69 is rocked at the proper times by an arm 70 connected with a strap 71, Fig. 3, which surrounds an intermittentlyoperated eccentric 72. The eccentric is mounted loosely on the hub of the continuously-rotating wheel 19, and is connected thereto automatically for half a revolution by a roll-clutch device 74, Fig. 7, when the latch 82 is liberated by the catch 80 or by the catch 81. The catch 80 is operated by the pull on the welt when a shoe is being removed from the machine, and the half-revolution of the eccentric which takes place before the latch 82 is caught by the catch 81 results in the operation of the device for severing the welt and gripping the loose end. The catch 81 liberates the latch 82 after the sewing operation has been started on another shoe, and the severing and gripping device is then withdrawn. In the gripping-device, the jaws are advanced hy the mutilated pinion 66 until the welt is embraced by them, and then the cutter 56 advances alone, its edge 65 forcing the jaw 55 upwards. On the return movement, a cam-surface 83 opens the jaws. The weltholder moves forward and holds the end of the welt during the first few stitches on a shoe, the bar 58 turning about the shaft 59 during this movement. The welt-measuring device through which the severing and holding mechanism is put into operation is shown in Figs. 8 and 11. It comprises a pulley 95 over which the welt W passes to the guide 4, and a clamp 97 which holds the welt at the completion of an operation, and frees it at the commencement of the next. While the clamp is on, the welt may be moved forward through a distance determined by a limiting-device comprising a stop-pin 100 working in a slot 101 in an arm 102 on the spindle of the pulley 95. The clamp is put on by a lever 52, which is actuated by a member co-operating with the cam-shaft 6 to throw off the thread tension when the machine is reversely driven before stopping. The lever 52 acts through a lever 107 having a cam shoe 105, and a spring-pressed plunger 98 acting on the clamp 97. The pull given to the welt, on removing the shoe, draws off the measured quantity of welt, and then acts through arm 102, rod 108, lever 109, and rod 110 to release the catch 82 and so put the severing &c. device into operation. The parts are brought back into position by a rod 111 connecting the rod 110 and the lever 52. Specification 17,328/08 is referred to.