GB185005A - Loop-taker actuating mechanism for sewing machines - Google Patents

Abstract

185,005. Fairweather, W., (Singer Manufacturing Co.). Aug. 12, 1921. Lock stitching.-In order to allow the needle to rise above the work before the needle thread loop is substantially distended by the looptaker while at the same time employing a loop-taking beak of restricted length and therefore a correspondingly smaller oscillation of the loop taker, the motion of the looptaker is retarded at the same time of taking the loop by the employment of an actuating-mechanism therefor including a pitman formed in two unequal sections, the pivot point of which is constrained by a radius-rod. The loop-taker shaft 24 is driven from the main shaft 5 through a crank 26, links 27, 28 of which the upper is the shorter and the pivot 29 of which is constrained by a radius-rod 36, and cranks 30, 33 connected by a link 34 to a crank 35 on the shaft 24. The effect of the linkage 27, 28 is to cause a dwell in the movement of the link 28, and therefore of the looptaker, as the crank 26 is passing through its highest point and an acceleration while passing through its lowest point. The shuttle having a beak 18, 17 supports a bobbin-case 19 and is driven by a shuttle-driver 23 mounted on the shaft 24.