GB687553A - Thread pull-off device for sewing machines - Google Patents

Abstract

687,553. Sewing-machines. FAIRWEATHER, W. C. (Singer Manufacturing Co.). Aug. 13, 1951, No. 18987/51. Class 112. Chain-stitching by eyed needles.-A thread pull-off comprises spaced thread-guiding eyes on a stationary member and a thread-engaging element secured to an actuating shaft and moving between the eyes to form a bight in the thread, the stationary member being adjustable by a manually rotatable knob having associated with it an eccentrically-disposed surface engaging the member. In the machine shown the needle-bar 20 is actuated by an oscillating shaft 16 connected by a link 17 to the rotary main shaft 14 which carries a looper of the usual form. The pull-off comprises a bent arm 34 fixed to the shaft 16 and projecting through a slot in the machine frame so that its end moves in an arc through a #-shaped part 38 of a member 33 to engage the needle-thread passing through holes in the limbs of the part 38 and draw it out into a bight; the member 33 is pivoted on the frame at its right-hand end and has in its middle an aperture engaged by an eccentric part of a friction-held knob 45, so that rotation of the knob causes angular adjustment of the member '33, the position of adjustment being indicated by a scale on the knob passing under a fixed pointer 48. The thread passes from a supply through an eye 25, tension device 26, the pull-off 38, a thread clamp 27, eye 28, take-up eye 29 in the needle-bar, check 30 and guide 31 to the needle; the clamp 27 is closed while the pull-off is actuated.