GB316506A - Rotary hook sewing machines - Google Patents

Abstract

316,506. Fairweather, W., (Singer Manufacturing Co.). Jan. 1, 1929. Lock-stitch hook sewing- machines. - In a vertical axis rotary hook sewing machine, the hook rotates more than once for each reciprocation of the needle and the bobbin carrier is given a short oscillation in a direction opposite to that of the hook by a finger. The hook 22 is formed in a member 21 rotated by the vertical shaft 15 from the bevel gears 13, 12. The gear 12 is rotated by the shaft 11 at the same rate as the needle reciprocating shaft. The gears 13, 12 are in the ratio 2 : 1 so that the hook rotates twice to one reciprocation of the needle. The hookmember encloses the bobbin carrier 17 which is held against rotation by a gap 27 therein engaging a fixed stop 29 on the cloth plate. To rotate the carrier slightly in a direction opposite that of the hook to enable the loop to clear the stop 29, a finger 30 engages the shoulder 28. The finger is mounted on a shaft 31 and is pressed against the shoulder by a spring 38. An arm 34 at the base of the shalt 31 carries a roller 36 running on the periphery of an eccentric 37 mounted on the shaft 11 to impart the necessary movements to the finger. A guard 40 is provided to prevent the fouling of the " chained-off " stitches by the hook. The bobbin carrier has a loop spreading finger 25.