Method for the determination of the switching moments for special functions of automatic sewing-machines

摘要

A method for the determination of the switching moments for special functions of automatic embroidery, straight-stitching-and sewing- machines with which the electrical signals which determine the switching moment are formed by logical switching operations in an electric or electronic control. The electrical signals fed to the control are produced by an angle coder (or a rotation pulse transmitter) which either is driven directly by the main drive shaft or indirectly by an auxiliary shaft; the angle coder delivers bit patterns, which bit patterns change constantly (or which pulse transmitter feeds pulses) from angle increment to angle increment of the main drive shaft (or which pulses are summed in a counter providing bit patterns at the output) and which bit patterns are compared in a logical switching operation control with other bit patterns representative of the different angular positions of the main drive shaft and being pre-programmed in the memory part of a memory/comparator; and upon bit pattern equality lead to the release of output signals for triggering of the special functions.