Control of needle movement, e.g. varying amplitude or period of needle movement

Full Title

Program-controlled sewing machines (with devices for automatically controlling movement of work-carrier D05B21/00; devices for stopping drive when sewing tools have reached a predetermined position D05B69/22) > Sewing machines having electronic memory or microprocessor control unit > characterised by control of operation of machine > Control of needle movement, e.g. varying amplitude or period of needle movement