GB171632A - Improvements in or relating to dobbies or heald machines for weaving looms - Google Patents

Abstract

171,632. Wilmore, A. S. Dec. 29, 1920. Dobbies; pattern surfaces.-In a dobby, the lifting-levers e, Fig. 1, carry swinging balks connected to pairs of upper catch-levers c and pairs of lower catch-levers c', Figs. 1 and 2, whereby the levers e can be so operated as to form a single or double shed. The catch-levers are controlled by feelers f, f<1> arranged in pairs, and are thereby moved out of the path of or remain in position to be engaged by corresponding pairs of upper and lower draw-knives b, b<1>. The feelers f control the lower ones of the lower catch-levers c' by means of arms f<3> and the upper ones of the upper catch-levers c by means of spring-controlled wires g<1>, whilst the feelers f<1> control the upper ones of the lower catch-levers c<1> by means of wires g<2>, and the lower ones of the upper catchlevers c by means of wires g. The wires g<1>, g<2> engage slots f<2> in the feelers f, f<1>, and, when the feelers are operated by ordinary pegs on the pattern chain, these slots prevent the wires g<1>, g' and corresponding catches from being operated so that only one of the catch-levers on a particular balk can engage and be drawn forwards by the draw-knives, and the lifting-levers are only given a single lift. Extra-long pegs are, however, inserted at intervals in the pattern chain, and these move the feelers to such an extent that the wires g', g<2> are operated. Consequently, both an upper and a lower catch-lever on a particular balk can engage and be operated by the draw-knives, the balk being thus drawn forwards at the top and bottom, and the corresponding lifting-lever being given a double lift. The draw-knives are operated by lifting-levers l, m.