data carrier 53 contains support points for the course of seams 44 45 to be controlled these support points are given as x and y coordinates of the seams 44 45 to be formed they constitute computer variables for the computer algorithm with which the remaining points of the seam can be calculated by linear or circular interpolation in addition special points of the seams are fed in such as e g corner points so that the computer program on reaching such support points can carry out special program branches to take account of the complicated control configuration in the vicinity thereof in addition the data carrier 53 supplies the computer 50 with information about the particular parts of the sewing curve where additional variables have to be taken into account the seam pattern is produced in such a way that the servomotors 21 22 are controlled by the computer in accordance with the course of the seams 44 45 in each case the encoder 16 supplies the computer 50 with a signal concerning the position of the needle in addition the positioning drive 7 is controlled by the computer 50 so that even in the case of complicated seam courses with discontinuities the needle only stitches in points of the.