Switching arrangement for the stitch control of a sewing machine

摘要

To reduce the necessary power of the control motors for the needle position and the fabric feed, these are controlled by a switching arrangement, in which the stitch control data read from the pattern memory are each stored in latch circuits. When stitch control data are extracted from the pattern memory, computing circuits form the respective difference between these data and the particular previously read data stored in the latch circuits. By adding these differences, a total value needed for controlling the needle position and the fabric feed is then calculated. When the total value is higher than a predetermined maximum value, the address counter of the pattern memory is counted down.