GB1078372A - Improvements in the threading of sewing machine needles - Google Patents

Abstract

1,078,372. Sewing machines. W. J. CLARKSON Ltd. March 14, 1966 [April 20, 1965; Aug. 18, 1965; Sept. 6, 1965], Nos. 16512/65, 35384/65 and 37916/65. Heading DIG. A mechanical threading device, Figs. 1 and 2, for the needle 36 comprises a hooked wire 12, 15 which passes through the needle eye to engage the thread 37a and which is carried at one end of a rod 9. The other end of rod 9 is secured to a lever 8 pivoted at 7 on a block which is slidable on a guide bar 5 on a bracket 1 secured to the machine. A second lever 17 also pivoted at 7 has a bar 18 extending therefrom and carrying a block 20 at its other end having an arcuate slot in which the end of rod 9 carrying the wire 12, 15 moves, the wire passing through a hole at the end of the slot. Levers 8 and 17 are interconnected by a coil spring 19 and lever 8 is biassed upwardly by a spring 13. An actuating lever 26 with an extension arm 30 and finger piece 31 is pivoted about 27 and biassed upwardly by a spring 32. A pin and slot connection is provided between lever 26 and lever 8 so that on depression of finger piece 31 thet levers 8, 17 and block 6 are moved down bodily until a projection 34 on block 6 engages the needle clamp 35, this position being such that the threader wire is in alignment with the needle eye. Continued depression of 31 results in arcuate movement of levers 8 and 17 until a locating groove on the end of block 20 engages the needle. Arm 8 then moves relatively to arm 17 and hook is passed through the eye of the needle to engage thread 37a. On release of the finger piece 31 the hook 15 draws the thread through the eye and the parts resume their original positions under the spring tensions. In a modification, Fig. 6, the hooked wire 12, 15 is carried on an arm 40 which is pivoted at 39 to another spring-loaded arm 38 on a fixed pivot 27. On actuating lever 47 has a roller 48 co-operating with a surface 49 on arm 40 so that on depression of lever 47 arms 40 and 38 move downwardly together, owing to a bias spring 46, until arm 38 engages the needle clamp. The threader wire is then in alignment with the needle eye and continued depression of lever 47 moves arm 40 against spring 46 to pass the hook through the needle eye.