Patent GB-316910-A (GB)
Title: Improvements in button sewing machines
IPC: D05B3/14
Filed: 1928-05-03
Abstract: 316,910. Armstrong, J. J. V., (Union Special Machine Co.). May 3, 1928. Button-attaching machines; needles, vibrating laterally.-A machine for attaching flat buttons has a laterally vibrating needle and a moving button holder, with means for adjustment for two- or four-hole buttons. Means are provided for automatically stopping the machine after a predetermined number of stitches have been placed through the button eyes. The needle 8 is carried on a bar 7 mounted in a gate 5, Figs. 1 and 13, swinging on a pivot 6 under the action of a rod 13 jointed to a lever 15 pivoted at 16 and actuated by the bifurcated rod 17 carrying a stud 21, which engages an eccentric groove 22 in a gear 23 driven by a gear 23<a> on the main shaft 12. The amplitude of the swing can be varied to suit the distance apart of the button eyes by moving the screw 19 at the end of the rod 17 along the slot 24 in the lever 15. The button B is held between jaws 43 - - 45, Fig. 5, carried by a plate 48 slidably attached to the presser foot 72 by tongues and grooves 73 to permit of the forward movement in the case of four-holed buttons, under the action of the lever 75, to which the plate 48 pivoted at the rear. The lever 75 is pivoted at 76, Fig. 13, and rocked periodically by an arm 79 through the bell-crank lever 92, 81, which has a boss 83 housing a spring-pressed stud 85, Fig. 15, which works in one of the grooves 90, 91 in the wheel 88 driven by the gear 23. Cam flanges on this wheel push the stud periodically into the appropriate groove to feed the button for stitching the two pair of holes. The amount of feed can be varied by moving the end of the rod 79 along the slot in a frame on the arm 92 of the bell crank 92, 81. When a two-hole button is to be attached, the stud 93 is moved to a position coaxial with the pivot 80 of the bell crank. A work-supporting plate 69 is also pivoted to the lever 75 but is not raised by the presser foot. The jaws gripping the button have corrugated under faces. Jaws 44 ,43 are pivoted on the plate 48 and have cam surfaces 53 for opening them by the roller 54, and cam surfaces 55 for closing them by the roller 56. These rollers are mounted on a plate 52 which carries the third jaw 45, and is operated by a finger lever 57 to grip or release the button. An adjustable stop 65 is provided to limit the movement of this lever. The four-motion looper 25 is operated in the known way to oscillate in the plane of oscillation of the needle. A loop retainer 28 is provided on a V-shaped arm 35, 29 mounted on a sleeve 30 which is moved laterally by a yoke 34 and arm 37 which takes the place of the usual feed bar, and is rocked by a cam 36 on the looper shaft, so that the retainer moves across the face of the looper to engage the needle loop at the correct time, and then move away from the looper to release the loop and allow it to pass off the end of the looper. Thread-cutters and thread-end holders.-When the stitches have been made through the holes in the button, as shown in Fig. 21, a thread deflector 98, Fig. 5, carried by an arm 100 on a sleeve on the looper shaft is moved by a link 106 pivoted to the arm 107 on a shaft 108, Fig. 13, is rocked by a roller 111 engaging the arm 115 to push the thread to the cutter 97. This severs the thread and holds the end by engagement with the spring member 99. Governing needle-thread. - After the thread has been so cut, the tension device 118 for the upper thread and that for the lower thread (not shown), are released by wedges such as 122, Fig. 15, operated by a cam 126 on the wheel 88 and lever 125, so that sufficient thread drawn from the supply to ensure a proper concentration of the loops on the first stitch of the next button. Starting and stopping gear. - To stop the machine at a predetermined time, a driving ring 131 on the main shaft 12 connected to the driving pulley 130 loose on the shaft by a spring- pressed friction clutch is released from an arm 135 on a collar 134 rigid with the shaft by the moving of a roller 137 along an inclined race by an arm 140 free on the shaft. A disc 143 is given a step-by-step rotation by a pawl 145 till a notch therein registers with a lug on the bar 141, which is then raised by a spring to engage the arm 140 and rotate it to push the roller 137 out of its coupling position, so stopping the machine.