Patent GB-190301232-A (GB)
Title: Improvements in Lockstitch Sewing Machines chiefly intended for use in the Manufacture of Boots and Shoes
Filed: 1903-01-17
Granted: 1904-01-07
Abstract: 1232. Cave & Sons, J., and Denne, M. T. Jan. 17. Boot-sole s t i t c h i n gmachines; j lock-stitch shuttle sewing-machines.- Relates to lock-stitch sewing-m a c h i n e s, for welting and turnshoe work, in which a semirotary barbed or hooked needle, a semi - rotary pricker or feed-awl, and a rotary shuttle moving in a plane at right-angles to the needle and awl are employed. Fig. 1 shows a machine of this type, embodying the present invention. Needles, hook, threading. - devices for. - The waxed thread A, Figs. 1, 4, and 7, is placed in the hook of the needle c by means of the finger l and hook p, which are mounted on spindles l<1>, p<2> in the bracket m fixed to the main frame. The spindle l<1> is hollow, and the thread A passes through it and through an eye on the finger l. In action, the finger l and hook p are moved from the position shown in Fig. 4 into the position shown in Fig. 7, so drawing the thread into the hook of the needle. The spindles l<1>, p<2> are operated by racks l<4>, Fig. 4, and p<5>, Fig. 7, the racks being actuated by toothed arms on bell-crank levers, which are jointed to similar levers operated by cams on the main shaft b, Fig. 1. In a modification, the rack p<5> is omitted, the spindle p<2> being geared to the spindle of the bell-crank lever which operates the rack l<4>. Lock-stitch shuttles and shuttle mechanism.- Within the shuttle race, Figs. 5 and 8, is mounted a ring q<1> provided with a finger q, which acts to spread the loop s, Fig. 8, of the needle thread, to facilitate the engagement of the loop with the hook f<1> of the rotary shuttle f, which carries the loop around the shuttle spool g'. The ring g' is operated by the toothed arm of the bell-crank lever q<3>, Fig. 5, actuated by a cam on the main shaft. The cover g, Fig. 8, which serves to retain the spool g<1> and to prevent it from rotating, is pivoted on a screwed spindle w, which is provided with a lever arm w<3> and engaged by a spring-controlled block w<2>. On turning the lever arm w<3> to close the cover, the cover moves with the arm by frictional engagement with the threads of the spindle w. By a slight excess movement of the arm w<3>, the cover is clamped laterally to its support and thus locked in position. Governing needle thread.-The waxed thread A is drawn from the usual tension disc k, Fig. 1, through a thread-lock, which consists of a stationary block t<1> and a cam-actuated sliding block t. The block t<1> is adjustable in position on an eccentric pin. For drawing off the required length of thread at each stitch, an adjustable cam-actuated sliding block u is employed. Frames.- The bracket m, which carries the thread-governing mechanisms &c., is separated from the main frame of the machine by a heat-insulating sheet m<1>, Fig. 1, of mica &c. Waxing thread.-The wax-pot v, Fig. 1, is removably supported on the jacketing-chamber v<1>, heated by bunsen burners v<2>. The thread A is drawn from the pot v through a tube v<7>, which is curved over the upper edge of the pot, the lower end of the tube v<7> being fitted with a atripper v<6> for removing superfluous wax from the thread.