Patent GB-162505-A (GB)
Title: Improvements in button sewing machines
IPC: D05B3/14
Filed: 1920-03-25
Abstract: 162,505. Darley, J. W. March 25, 1920. Button-attaching machines.-In a machine in which a button is stitched to a garment so as to be separated therefrom by a neck of thread, mechanism is provided which winds another thread around the said neck and ties the winding thread ends together in a reef knot. The ends are then cut close to the knot, leaving the supply end of the thread held by the knotting device for the next operation. The sewing shaft carries fast and loose pulleys 16, 30, while the winding, knot-tying, and thread-cutting devices are operated from a shaft 312 by grooves in a cam disc 144, Fig. 3, mounted in a cam case 89 which supports the said devices. The button chuck, Fig. 5, comprises three mutually-adjustable jaws 150, 151, 152 pivoted to a carrier 148 which is adjustably secured to a screw 144, whereby the button may be raised or lowered to vary the length of the neck of attaching thread. The carrier 148 is intermittingly jogged to place the holes in the button alternately in line with the descending needle. Supported by a bracket of the cam case is a bevel wheel 366 which surrounds the button chuck and to which is pivoted tamgentially of the wheel the winding arm 384 supplied with thread from the bobbin 369 carried by the wheel 366. The wheel 366 is rotated by a wheel 345 on a shaft 105, Fig. 13, which is driven either by the loose bevel wheel 348 or by the shaft 104 geared to the shaft 312. A worm 342 on the shaft 104 drives the cam disc 144, a groove in which actuates the lever 517 having teeth meshing with the wheel 348. Rotating with and slidable along the shaft 105 is a clutch sleeve 352 which is moved axially by a lever 355 pivoted at 473 and urged by a spring 467 in a direction to engage the sleeve with the wheel 348. The lever 355 carries a pin '475 which passes through a slot 452 in a radially-movable arm 451, and engages a cam piece 481 on the disc 444 which also contacts with a pin 455 in the arm 451. Thus when the cam 481 engages a pin 455, the arm 451 is moved outwardly swinging the lever 355 against the action of spring 467 to clutch together shafts 104 and 105, and the winder gear 366 is rotated rapidly until the cam 481 passes the pin 475. The number of turns of winder thread may be varied by varying the distance between the pins 455 and 475. After the winding operation, lever 517 controls the winder gear and rotates the wheel 366 slowly half a revolution in a reverse direction while at the same time the arm 384 is swung outwardly, so that the thread is laid in the knottying devices which are located just outside the circle described by the winding arm 384. The outward swing of the arm 384 is caused by descent of a lever 445 which is actuated by a cam-operated lever 334 and engages a roller 388 on a second arm integral with the arm 384, Fig. 5. Knot-tying devices.-The knotter 603, Figs. 43 and 48, is carried on the end of a sleeve 539 and is bored internally for a twister 572 having threadclamping jaws 636, 637, Fig. 49. The sleeve 539 carries gear teeth 554 and is oscillated by a camactuated lever 531, Fig. 3, while the twister 572 is rotated through bevel gearing by a shaft 540 which carries gear teeth 548 engaged by a camactuated lever 534. After the arm 384 has laid the thread in the knotter, as shown in Fig. 70, the twister 572 rotates to twist the thread-ends together and the arm 384 returns while at the same time the knotter is rocked through 180‹ to allow the thread-twist to slip down the thread, as shown in Fig. 72, return movement of the knotter and outward movement of the arm 384 serving to tighten the knot against the button thread-neck, the whole operation being then repeated to form a reef-knot. Sewing-machines; thread-cutters and threadend holders.-After the knot has been tied, the arm 384 again returns to the knotting-devices and the thread ends are cut close to the knot by cutters 674, 675, Fig. 5, carried by a lever 648 which is spring-pressed toward outward position and is advanced, through connections comprising the link 660 and boss 512, by the lever 445, the roller 510 on the boss 512 engaging the lever 686 to close the cutters as they advance. Connected by a latch to the lever 648 to be advanced thereby is a lever 649 to which is pivoted a lever 699 the end of which is provided with hooks. In the advance of levers 648, 649 the latch is tripped by the post 136 and the lever 649 is swung rapidly back to outward position by a spring, the hooks on the lever 699 engaging the thread-ends and driving them against knife-edges 694, 695, Fig. 48, on the knotter 603 to cut the threads from the knotter. During the withdrawal of the lever 699 a cam thereon contacts with the roll 621 on the lever 585 to cause its end 615 to engage the pin 631, Fig. 49, of the twister to open the jaws 636, 637 and release the thread-end held thereby, while one of the hooks on the lever 699 draws the other thread-end into the jaws to be held throughout the next operation. Starting and stopping gear.-The rotation of the sewing shaft and of shaft 312 is controlled by a lever 217 pivoted at 244, Fig. 7, to the frame. An arm 251 on the lever carries a roller 253 which presses against the lever 20 to remove its end 19 from the stop-cam on the sewing shaft and shift the driving-belt, when the lever 217 is swung by the action of the treadle-operated lever 234 on the roller 269 carried by the lever 217. A detent 40 holds the stop-piece 19 in'this position. On the lever 217 is a boss 254 in which is a spring-pressed pin 259, Fig. 9, the end of which engages behind a lug 291 on the lever 273 which carries the stoppiece 285 and belt-shifter for the shaft 312. After one rotation of the sewing shaft, a cam piece 44 releases the detent 40 and the lever 20 is swung by a spring 29, Fig. 2, to stop the sewing shaft, this movement of the lever 20 swinging the lever 217 counter - clockwise, Fig. 7, and causing the pin 259 to swing the lever 273 against the action of a spring 310 to withdraw the stop-piece 285 and start the shaft 312. At the end of a rotation of the disc 444, a lug thereon engages a pin 308, Fig. 3, on a lever 297, thereby swinging this lever and causing a pin 295 at its other end to disengage the pin 259 from the lug 291, and allow the spring 310 to swing the lever 273 to stop the shaft 312. The sewing operation may be performed alone, being followed by the winding operation, by preventing the engagement of the pin 259 behind the lug 291 by means of a cam piece 220, Fig. 9, which is moved manually into engagement with a head 260 on the pin 259, while the winding and knot-tying operations may be performed without the previous sewing operation by manually swinging the lever 273 to disengage the stop-piece 285. Attached to the cam case 89 by an extension 187a, Fig. 2, is a presser plate 131 and in order to allow insertion and removal of work the cam case and its attached parts may be lifted bodily by a treadle-operated lever 57 one end of which engages a part 121 of a bracket 119 on the cam case. Mounted on a sleeve carrying the starting lever 234 is an arm 239 which passes beneath the bent end 240 of the lever 75 when the starting lever is operated, thereby preventing lifting the cam case and presser plate while the machine is running. Conversely, while the cam case is in raised position, the end 240 prevents movement of the arm 239 and consequently of the lever 234 to start the machine.