GB690521A - Improvements in sewing machines - Google Patents

Abstract

690,521. Sewing-machines. INDUSTRIEWERKE KARLSRUHE AKT.-GES. April 10, 1951, No. 8246/51. Class 112. To minimise vibration in a feed-off-the-arm machine having the work arm 10 connected to the top arm 5 by an oblique arm 9, the parts in the work arm are actuated from a shaft 12 placed parallel to the work arm in the lower end of the oblique arm. The looper mechanism is modified to give quick movements with a long dwell in the forward position. In the form shown, the shaft 12 is driven from the main shaft 6 by a shaft in the oblique arm bevelgeared to both the other shafts, the lower bevel gears being shown at 14. Making stitches involving several needles.- The looper, which co-operates with three needles, is carried by a shaft 47 reciprocated in known manner, to give the needle-avoiding movement, by a connecting rod 30 attached to a slotted arm 29 on a cross-shaft 26 oscillated by an eccentric 22 on the shaft 12. The shaft 47 is oscillated by a crank 31 on one end of the shaft 12 connected by a link 32 to the upper end of a lever pivoted at 34 and linked at its lower end to an arm 37 in the hub of which the shaft can slide but not rotate. The looper arc is flat because the shaft 47 is low in the arm. The forward end of the shaft 12 carries a cam-shaped disc 20 entering a slot in a thread guide 21 to control the looper thread. Feed by dogs.-The feed-lift movement is derived from an eccentric 17 on the shaft 12, and the feed-advance movement from a slotted arm 27 integral with the arm 29. Frames.-The mechanism in the work arm 10 is carried by a frame member 10 of welded construction, giving increased space.