GB988688A - Thread selector mechanism for stitching machine - Google Patents

Abstract

988,688. Sewing machines. AMERICAN MACHINE & FOUNDRY CO. Sept. 6, 1961 [Sept. 6, 1960], No. 32055/61. Heading D1G. A sewing machine comprises a plurality of thread spool support elements, means for positioning the selected thread adjacent a needle, and means for threading the needle with the selected thread. A button sewing machine, as described in Specification 712,548, is provided with spools 10 mounted on respective pins 14, 16, 18, 20 carried by a fixed bracket 12. The threads pass through holes 22 in a fixed bracket 24, and then through holes 26 in a fixed block 28. The latter is framed with vertical slots 44 in which are pivoted on a horizontal pin 42 bars 34, 36, 38, 40. Each of the latter has a weighted outer arm 46 and an inner arm 48 which is directed towards the needle bar 80 and is formed with holes 30, 32 through which the thread successively passes. When the free end T of a thread is pulled downwards, the corresponding arm 48 displaces a nose 54 on a lever 56 pivoted at 58. Lever 56 is then returned to its original position by a weighted arm 57. When the thread is released, arm 48 rises to an upper position in engagement with nose 54, and can move to a lower position, shown dotted, in which arm 46 engages block 28. A hook 60 is carried by a rod 64 fixed to an arm 66 which is pivoted on a fixed horizontal pin 68 and is biased upwardly by a spring 72 against a fixed stop 76. When arm 66 is moved downwards, hook 60 passes through the eye of the needle N and may be engaged with the free end T of the selected thread. On release of arm 66, hook 60 draws end T through the needle eye. During the sewing operation, arm 48 will oscillate between its upper and lower positions to take up thread slack and to maintain a uniform thread tension. Specifications 900,007 and 966,606 also are referred to.