GB229538A - Improvements in shoe sewing machines - Google Patents

Abstract

229,538. Sokal, S., (Adrian & Busch). Dec. 13, 1923. Sewing-machines; lock stitching by hooks.-A take-up arm 34, Fig. 9, specially suitable for a hook-needle sole-sewing machine is oscillated (so t'hat its free end A moves steadily in one direction to deliver the thread for the formation of the loop and rapidly in the opposite direction to take up slack), by mechanism comprising a link 37, a radius arm 44, and a link 43 pivoted at the pivot point XXVI of the members 37, 44, and connected at XXV to the extension 42 of a member 40 of a four-bar linkage driven by a rotating member 38. By this arrangement the pivot XXV of the link 43 is caused to move in a closed curve and the pivot XXVI along the arc of a circle. Small movements along the line x<1>, y<1> forming part of this closed curve cause large movements along the arcuate line x<11>, y<11>. The rotating member 38 may be an eccentric disc 38, Fig. 6, the member 40, 42 being constituted by the strap 39 having extensions 40, 42.