Sewing machine

A sewing machine comprising a sewing table, on which a workpiece such as a floor mat is mounted, a sewing means provided with a vertically oriented needle for sewing an edge of said workpiece mounted on said sewing table, a sensor means for continually monitoring an outer contour of said workpiece and transmitting monitored information, said sensor means including a swing arm which is swingable about an axis parallel to an axis of said needle and is provided with a detecting bar abutting against the edge of said workpiece, and a means for monitoring a swing angle of said swing arm, a feeding means for turning said workpiece in accordance with said contour of said workpiece so as to successively feed the workpiece into a sewing area, and a control mechanism for controlling said feeding means in accordance with the monitored information transmitted from said sensor means.

A sewing machine for sewing an edge of a workpiece such as a floor mat which is mounted on a sewing table, comprising a sensor means for continually monitoring an outer contour of said workpiece and transmitting monitored information, a feeding means for turning said workpiece in accordance with said contour of said workpiece so as to successively feed said workpiece into a sewing area, said feeding means including a plurality of feeding rollers which are reversibly rotated and arranged such that the rotational axes thereof are oriented towards a needle in the sewing area, and at least one pressing means which moves towards and away from the corresponding feeding roller for timely pressing said workpiece in cooperation with said corresponding feeding roller, and a control mechanism for controlling said feeding means in accordance with the monitored information transmitted from said sensor means.

A sewing machine for sewing an edge of a workpiece such as a floor mat which is mounted on a sewing table, the sewing machine comprising a sewing means for sewing at a predetermined feed pitch and including a needle, a sensor means for monitoring an outer contour of said workpiece by abutting against the edge of said workpiece and transmitting monitored information, a feeding means for turning said workpiece in accordance with said contour of said workpiece so as to successively feed said workpiece into a sewing area, and a control mechanism for controlling said feeding means and said sewing means in accordance with the monitored information transmitted from said sensor means, wherein the feed pitch of the sewing means is set at a smaller amount relative to a standard when sewing an outwardly curved portion, and is set at a larger amount when sewing an inwardly curved portion, while the feeding means turns said workpiece at a relatively low speed in said outwardly curved portion, and turns said workpiece at a high speed in said inwardly curved portion, whereby said workpiece can be substantially equally sewed.