Machine à coudre permettant de réaliser automatiquement des points formant des motifs divers

摘要

877,907. Electric selective signalling systems. MEFINA S.A. May 2, 1958 [May 9, 1957], No. 14077/58. Class 40 (1). In an electric digital-to-analogue converter incoming binary digital electric signals are converted into a corresponding axial movement of a member 25, Figs. 1 and 2, by a device comprising a continuously rotating shaft 1, Figs. 1 and 3, which rocks via eccentrics 2a a series to two-ended levers 3, Fig. 3, there being one lever for each digital position, a fixed shaft 8 which carries a series of pairs of levers 6, 7 coupled to corresponding levers 3 by links 4, 5, and a series of pairs of solenoids having series wound input coils 16a, 161a, Fig. 3, and a normally energized biasing winding 17. In operation with no input signals the end 15 of the lever 7 is held fixed by the biasing current through coil 17 and so as the shaft 1 rotates lever 6 oscillates, whereas when a signal is applied to the input coils 16a, 161a, the end 14 of the lever 6 is held fixed and lever 7 oscillates. Which of the two levers 6 and 7 oscillates is detected by a cam 9a (see also Fig. 5) which is either forced to the position shown in Fig. 3 if lever 6 is oscillating or to the symmetrically opposite position if lever 7 is oscillating, and this results in cam 9a either being moved axially along the shaft 8 or not by virtue of its cam profile 18, Fig. 5. Hence as a result of an applied pattern of input signals a series of cams 9, Fig. 1, are correspondingly positioned to give a resultant axial movement to a member 12 which is transmitted by rods 19, Fig. 2, pressing on levers 20, Figs. 1, 2, and 4, pivoted on pins 21 to protrusions 24, Fig. 1, in the member 25. Limited angular displacement of the member 25 is possible to vary the mechanical advantage of the coupling between the member 12 and the member 25.