Microprocessor controlled electronic sewing machine

Abstract

The present invention is an improved electronic type sewing machine in which a microcomputer integrated circuit arrangement, such as a master/slave microprocessor configuration, is employed to effectuate stitch position coordinate servo control for both bight and feed through digitally closing the position servo control loop. The sewing machine includes actuator means for adjusting the transverse position of the needle bar means and the positional displacement of the feed means in response to control signals provided thereto and static memory means, such as a read-only-memory, for retrievably storing a plurality of different predetermined stitch patterns each having associated retrievably stored bight and feed data corresponding to predetermined positional coordinates of the needle bar and feed means for defining associated stitch position coordinates for the stitches comprising the stitch patterns. The microcomputer arrangement is connected to the actuator which it controls as well as to the static memory containing the requisite data. A transducer arrangement is connected between the actuator controlled and the digital input of the microcomputer for providing a digital input signal to the microcomputer representative of the actual position of the actuator. Where the master/slave microprocessor configuration is employed, the slave microprocessor is employed to close the position servo control loop and the master microprocessor is employed to process the stitch position coordinate data and provide the desired digital position input to the slave microprocessor for digital position error comparison with the actual digital position input.