Abstract: A method and apparatus for detecting an aberrational stitch, normally a skipped stitch, in real time in a sewing apparatus. Movement of thread is detected, and a signal is generated if the thread is moving. At the same time, revolution of the handwheel of the sewing machine is detected, and pulses representative of the revolution are generated. The pulses are accumulated so long as the thread is moving, and the accumulated pulses are compared with a minimum number of pulses for a period of time. After one revolution of the sewing machine handwheel, representative of one stitch, the results of the comparisons are used to determine an aberrational stitch, and if a malformed stitch is detected., the sewing apparatus is stopped.

Abstract: A sandwich synchronizer for a sewing apparatus. The synchronizer is formed to be interposed between the rotatable drive shaft of a sewing machine and the rotary encoder for the sewing machine. The sandwich synchronizer includes a rotatable synchronizer shaft, an encoder for detecting rotation of the synchronizer shaft, and means at either end of the synchronizer shaft for attaching to the rotary encoder and the rotatable drive shaft. The sandwich synchronizer is a universal synchronizer which can be used in any sewing apparatus, no matter what the manufacturer and no matter what the output of the rotary encoder for that sewing apparatus.