Patent GB-308221-A (GB)
Title: Improvements in or relating to machines for operating upon boots or shoes
IPC: D05B15/04
Filed: 1929-03-19
Abstract: 308,221. United Shoe Machinery Corporation, (Assignees of Hood, C. E.). March 19. 1928, [Convention date]. Sewing-machines; driving; work supports, trimming or cutting.-In a boot manufacturing machine, particularly a machine for sewing welts, a device is operated on placing a boot in the machine to adjust the mechanism for the size of boot being operated upon. The invention is described with reference to a machine for slashing welts to enable them to be laid round the toe of the boot, and for sewing the welts to the boot, of the kind described in Specification 100,112, with stripping mechanism as described in Specification 5453/12. When the machine is at rest, the parts are in the positions shown in Fig. 2, pawls 92 and 86 being held out of engagement with the ratchet wheel 80 and the lever 114 engaging one of the shoulders 120 of a stop disc 116. On placing a boot in the machine, the boot contact lever 100 is displaced to the right against the pressure of its spring 118, Fig. 3, a distance corresponding to the size of the boot and the lever 114 is raised a corresponding distance so that the stop disc 116 and the associated cam disc 65 and ratchet wheel 80 are allowed to move in a clockwise direction under the action of the spring 98 till the lever 114 comes into contact with the stop shoulder 120 which will position the parts correctly for operation during the sewing of the boot of that size. The lever 114 has a series of teeth 122 which, on starting the machine, are engaged by the pawl 124 pivoted at 66. The spring 126 holds the pawl 124 in engagement with the teeth. To regulate the movement of the cam disc 65 and ratchet wheel 80 under the action of a spring 98, a spring plate 127 is arranged to bear against the face of the disc 116. When the machine is started by pulling down the rod by a treadle, the pawls 92, 86 engage the teeth of the ratchet wheel and cam disc 65 against the tension of the spring 98 till the pawl 86 rides on the blank surface 96, when forward movement of the ratchet wheel and cam stops and the parts are held stationary by the stop pawl 92. During the partial rotation of the ratchet wheel and cam, the end of the lever 68 passes into the high part of the cam groove 64 and the welt slashing devices 16, 36 are rendered active to slash the welt, after which the end of the lever rides off the high part of the groove and the slashing ceases. During this partial rotation of the ratchet wheel and cam, a cam surface on the disc 116 raises the lever 144 to its highest position and swings the contact place 104 into a position where it will not interfere with the manipulation of the boot by the operator. The parts remain in this position with the slashing devices inoperative and with the cam disc 65 in its advanced position till the machine is stopped by the release of the treadle and upward movement of the rod. At this time, the pawls 86, 92, and 124 are lifted out of contact with the ratchet teeth so that the ratchet wheel and cam disc 65 are returned to their original position by the spring 98, and the lever 114 drops, permitting the boot contact lever 100 to move forward under the action of its spring 118. To stop and restart the machine without rendering the slashing devices inoperative, e.g. in the case of a broken sewing thread, a horizontal disc 148 with a sloping cam surface 154 engaging a stop 156 on the link 128 is provided. To stop the machine, the disc 148 is rotated by a handle 16, bringing the cam 154 under the stop 156 to raise the link 128 and lift the pawls 86, 92 and 128. The welt is held in a support 36 secured to the slide 18. The support is angularly adjustable by a screw 62 to adjust the welt for changing the length of the slit made by the slashing knife 16.