Knopfaufnaeh- und -aufheftmaschine mit Fuehrungen fuer Nadel und lose O-Fadenenden

900,007. Sewing machines. AMERICAN MACHINE & FOUNDRY CO. March 21, 1961 [April 5, 1960], No. 10336/61. Class 112. In a sewing machine having a double-pointed needle which is passed back and forth through the work by a pair of opposed needle bars, each needle bar has operatively associated therewith a rotary thread-puller for alternately pulling the loose end of the stitching thread out of the work. As shown, the machine is a modification of the button-sewing machine described in Specification 712,548. The needle 36 is alternately gripped by respective upper and lower reciprocating needle bars 16 and 18. When the upper needle bar descends slightly from the top of its stroke to throw a thread loop, the latter is seized by a beak 102 at the end of a rotary arm 41, and the loose end of the thread is thereby carried into and through an arcuate tubular channel 104 formed with an arcuate slot 112 through which the shank of beak 102 projects. Arm 41 is adjustably fixed to an arm 80 rigid with a shaft 82 driven from the main shaft 64 via a train of gearing 62, 94, 92, 88, 86, 84. Channel 104 is fixed to a bracket 108 which is hinged to the doffer arm 110 of the machine and is provided with a guard plate 109. The loop thrown by the lower needle bar is seized by a beak 70 on a rotary arm 39, to carry the loose end of the thread through a fixed arcuate tubular channel 72 formed with an arcuate slot 78 for the shank of beak 70. Arm 39 is adjustably fixed to an arm 42 rigid with a shaft 44 driven from the main shaft 64 via a train of gearing 62, 60, 58, 54, 52, 50. The needle is supported in its downward stroke by the curved end 119 of an oscillating arm 118 rigid with a shaft 120. An arm 122 on the latter has a forked end 124 embracing a roller 126 on one arm 128 of a double-armed lever, the other arm 130 of which carries a roller 132 biased by a spring 138 against a cam 134 on the rotary shaft 82.