Automatic zigzag sewing machine control - by neon lamp scanning pattern and photocells controlling thyristors for needle piston movement

摘要

An electric sewing machine is automatically controlled to sew a stitching pattern on a drawing by a neon discharge lamp and two conical luminaires to scan the pattern. Transducers convert the reflected optical signals into electrical signals and control the posn. of a piston through two coils and two thyristors. The piston is linked to the sewing needle and governs its posn. This system is not limited to a certain width of variation of the pattern. There are no cams which have to be exchanged and the shape of possible patterns is not limited to those given by the contours of the cams.