GB913799A - Rotary hook for sewing machines - Google Patents

Abstract

913,799. Sewing - machines. FAIRWEATHER, H. G. C. (Singer Manufacturing Co.). Aug. 26, 1961, No. 30844/61. Class 112. A sewing-machine rotary hook comprises a cup-shaped body formed with a loop-seizing beak and an internal circular raceway, and a bobbin-case carrier having a peripheral rib journalled in said raceway, the cup-shaped body having a plurality of holes each of which is formed partly in the base and partly in the side wall of said body to permit the passage of air during the rotation thereof. A cup-shaped body, secured by screws 13 to the driving shaft 6, has an end wall 9, a side wall 10 and an internal circular raceway 20, part of the outer side of which is open and which is closed by a gib 21 secured by screws 22 to the hook body. A bobbin-case carrier 27 is formed with a peripheral rib 29 journalled in raceway 20, and is also formed with a radial flange 33 having external and internal notches 34 and 38 respectively, engaged by a respective fixed detent 35 and affording passage for the needle 3. The hook has a series of holes 39, each of which is formed partly in the end wall 9 and partly in the side wall 10, and the axis A of which is inclined outwardly from the shaft 6 and backwardly in relation to the direction R of rotation of shaft 6. Air currents C flow through the holes 39 during the rotation of the hook body to prevent the accumulation of lint at the sewing point. The gib 21 has an axial extension 40 adapted to counterbalance the effect of the holes 39, and the edge 41 of extension 40 is positioned adjacent the needle 3 so as to prevent accumulation of lint on the loop-forming side of the needle.