Dobby with correlated and superimposed cams for the desmodromic operation of weaving looms

摘要

Dobby (1) for the desmodromic operation of warp frames (2) in weaving looms, comprising a plurality of coaxial cams (4,5;204,205) which are coupled together in pairs and correlated, for the positive operation, in both directions, of the lever mechanisms (2a) for operating the frames (2) of weaving looms, wherein each pair of cams (4,5;204,205) is associated with a pair of wheels (8,9;208,209) lying in axially staggered planes and rigidly connected to a rocker arm (7;207) for operating the arms (2a) of the frames (2), each pair of cams (4,5;204,205) being formed by a first cam (4;204), the dimensional profile of which is smaller than the dimensional profile of the other cam (5;205) of the pair, the locus of the points described by the smaller cam remaining always within the locus of the points described by the larger cam.