Compact stitch-selector mechanism for zigzag sewing machines - having co-axially mounted stitch-cams and stitch-length control link

摘要

A zig-zag sewing machine having several coaxial stitch cams controlling the fabric feed and the overstitch, and with means for varying the magnitude adn direction of the feed motion, has a stable and compact arrangement of the adjustment mechanism whereby the control link for the magnitude and direction of the feed dogs is mounted coaxially with the stitch cams. The control link is rotatably mounted on the camshaft itself, and carries a toothed quadrant which engages a second quadrant mounted on an axle parallel with the camshaft, to which is attached a follower which rests between two inverse cam tracks on the face of a manual setting dial. This construction permits the selector mechanism to be housed in the base of the machine instead on in the pillar or the arm. This eliminates a substantial mass of heavy linkages, making the mechanism easier to construct and maintain, and also making it more stable, and less prone to large, undesirable vibrations at high speeds.