Patent GB-650107-A (GB)
Title: Improvements in button-stemming machines
IPC: D05B3/14
Filed: 1947-11-06
Abstract: 650,107. Sewing-machines. BATA, NARODNI PODNIK. Nov. 6, 1947, No. 29628. Convention date, Nov. 16, 1946. [Class 112] In a machine for winding thread about the thread stem by which a flat button is attached to a garment, the winding thread is introduced by a needle between the threads of the stem in loop which is held by a catcher and is passed round the button the required number of times by a shuttle, the thread then being fastened off between the stem threads and severed. Flat buttons, attaching; thread-cutters and thread-end holders.-In the form described, the thread loop cast by the needle is held by a finger and passed over the button a number of times by a shuttle. The button is inserted into a drum 14 through an open part of the face of the drum, its stem resting in a notch in the closed part of the drum face so as to be approximately co-axial with the main shaft 4, which operates the shuttle 10 surrounding the drum. The drum 19 is held stationary by a fixed finger 25 engaging a short slot jn the drum, and a cam-operated finger 27 moves the drum, as permitted by the slot, at each revolution of the shuttle to allow the thread to pass this finger. The thread passes to the needle 53 from a bobbin 99 between a bolt 102 and brake shoe 103, and through a tension device 105 and eyes on an arm 49, actuated by a cam on a shaft 45, driven by worm gearing 6 and gears 35, 44 from the shaft 4, and an arm 30, actuated by a cam on the shaft 4. The needle 53, carried by an arm 51 which is pivoted at 52 and actuated bv a cam 50 on the shaft 45 passes through the thread stem, from the initial position shown in Fig. 3, and retires just clear of it, the initial thread end being held between a resilient member 63, which also serves to guide the needle, and a displaceable hooked cutting member 66 adapted to co-operate with a blade 62. The members 63, 62 are rigidly carried by an arm 58, which is also pivoted at 52 and actuated by a cam on the shaft 65, and the member 66 is carried by a block 65 slidable in the arm 58 under the action of a camoperated crank 70. The arms 51, 58 are guided by slots in a bracket 56. The thread loop left by the 'needle is engaged, as the needle retires, by a catcher 76, which is moved to the left and inverted, after engagement, to hold the loop during the winding: the loop is opened by a hook on a fixed member 110. The catcher is pivoted in a carrier 80 on the end of a shaft 81 movable longitudinally by a cam-actuated lever 89 and angularly by a cam-actuated gear sector 93, while a rod 84 is slidable in an axial bore in the shaft 81 by a camactuated lever 85 to oscillate the catcher on its pivot by means of rack teeth engaging teeth on the catcher. The nose 14 of the shuttle 10 engages the thread loop and passes it round the drum, and thus wind the thread stem of the button, at each revolution, each turn being pulled tight by the arm 30, and finally the catcher 76 returns to its original position and sheds the loop, whereupon the members 62, 63, 66 cut the thread and hold the end for the next cycle. (These members and the needle are retracted clear of the drum after the first few turns, until the final movement.) If it is desired to have a smaller number of winding turns than is provided by the full cycle of operations, the thread loop is carried clear of the shuttle during the latter part of the cycle by an arm 43 which is actuated by an adjustable cam 37 on the shaft of the gear 35.