Abstract: A processing and sewing machine arrangement for preparing a seam which is uninterrupted on a seam side facing the needle of the sewing machine. The arrangement includes a shuttle thread disturbance detection arrangement and a control arrangement activating a stopping arrangement for stopping the sewing machine after the shuttle thread disturbance has been detected and after a stitch formation cycle which has been begun is completed. A regulating mechanism for setting stitch length is set into a reverse stitching mode by the control arrangement while the fabric being sewn is moved backward by one stitch length. After the shuttle thread has been fed in, thread is knotted by at least one stitch with the needle thread in the same insertion hole in which the old shuttle thread is located such that the old shuttle thread is correctly knotted with the needle thread.

Abstract: Thread monitor for monitoring double lock stitch shuttles or hooks and chain stitch machine shuttles or loopers. During normal operation of the sewing machine, the shuttle thread is used as a reflection surface. The scattered light beams reflected by the thread enter photodetector 10 of the thread monitor 8. If the support surface 7, 28 is covered by thread, light beams will reach said photodetector 10, as a result of which a control circuit 12 connected to it issues a warning signal.

Abstract: A lighting device for a sewing machine which has a housing with a base and an upright portion mounted on the base and an arm carried by the upright portion which overlies the base in which there is positioned a movable thread needle which operates below the arm to sew materials and which comprises a light source carried in the housing and a flexible sheath supported in the arm of the housing and extends outwardly of the arm in the vicinity of the needle. The sheath carries at least two light guides which have first ends exposed to the light source mounted on the sewing machine housing and an opposite second ends which extend out of the sheath in the vicinity of the needle. The sheath and the light guides are bendable so as to arrange the second ends of the light guide in a selected manner for illuminating selective areas in the vicinity of the needle.

Abstract: A sewing machine having a thread monitor associated with a bobbin mounted for rotation. The bobbin includes first and second reflecting surfaces associated with an inner side of a second bobbin flange, and first and second light outlet openings associated with a second bobbin flange. A light source is provided for directing light toward the reflecting surfaces. A light receiver is positioned so as to receive light emerging from the first and second outlet opening. The light receiver produces signals representing the light intensity received by the light receiver. A Schmitt trigger provides a pulse to a microprocessor coinciding with a revolution of the bobbin. For each revolution of the bobbin, an A/D converter converts signals received from the light receiver into digital signals which are compared. The digital signal having the maximum value for the revolution is stored in a memory and then compared with a subsequent maximum value.

Abstract: A method of sewing the corners of a double seam, employing a two-needle machine the two needle rods of which each may be mutually independently engaged and disengaged. The method uses control means to arrive at the corner point of the inner seam, disengaging the internal needle rod, furthersewing to the corner point of the outer seam, stopping the sewing machine with the outer needle penetrating the workpiece, then rotating the workpiece, sewing the thus rotated outer seam, and engaging the inner needle rod.

Abstract: A workpiece prepuncturing device for use with a sewing machine having drive means for reciprocating a needle and means for feeding a workpiece into association with the needle to sew a stitch comprises a perforating tool which is located at a spaced location from the needle which is comparable to a multiple of the stitch length. The perforating tool cooperates with a counter tool which is mounted on the opposite side of the workpiece and is movable toward and away from the workpiece in timed relationship to the speed of the feed and the reciprocation of the perforating tool. The counter tool is supported in a base portion of the sewing machine by an elastic suspension, and it is in drive connection with the main shaft of the machine which operates the needle and the feed for the workpiece.

Abstract: A pocket stitch is sewn on cut workpiece parts which are guided into operative association with a reciprocating needle which effects a straight stitch when it is reciprocated and also may be swung from side to side to effect a zig-zag stitching. The workpiece is guided so as to form at least one substantially U-shape straight stitch having spaced apart leg portions and the stitch is secured by guiding the workpiece to effect the formation of a barring stitch at the ends of each leg portion by causing the needle to form a zig-zag stitch at such location. The sewing machine for sewing the pocket cuts includes a needle bar which may be swung during the operation of the drive mechanism or the zig-zag control mechanism may be shifted to effect the formation of a straight stitch. A rotatable cam which is driven by the drive mechanism positions a clamping plate having a substantially U-shape slot which permits reciprocation of the needle through a workpiece carried thereon.

Abstract: A pocket stitch is sewn on cut workpiece parts which are guided into operative association with a reciprocating needle which effects a straight stitch when it is reciprocated and also may be swung from side to side to effect a zig-zag stitching. The workpiece is guided so as to form at least one substantially U-shape straight stitch having spaced apart leg portions and the stitch is secured by guiding the workpiece to effect the formation of a barring stitch at the ends of each leg portion by causing the needle to form a zig-zag stitch at such location. The sewing machine for sewing the pocket cuts includes a needle bar which may be swung during the operation of the drive mechanism or the zig-zag control mechanism may be shifted to effect the formation of a straight stitch. A rotatable cam which is driven by the drive mechanism positions a clamping plate having a substantially U-shape slot which permits reciprocation of the needle through a workpiece carried thereon.