Abstract: An automatic sewing machine for producing a seam having a fastening seam and a tacking seam is installed with a sewing head having a bearing bracket with two bearings which are arranged at a distance from each other for receiving a reciprocating needle bar including a needle. A sewing head comprises a drive mechanism to selectably impart jogging movements to the needle bar, wherein the movements form a transmitting ratio with respect to the reciprocating movement of the needle of 1:1 or 1:2.In order to render possible a shifting of the needle jogging movement during the operation of the machine and under full load, the two bearings guidingly receiving the reciprocating needle bar are oscillatingly drivable independently of each other wherein one bearing is oscillatable at a transmitting ratio of 1:2 and the other bearing is oscillatable at a transmitting ratio of 1:1. Both bearings are drivingly connected to individual drive parts each of which is independently engageable.

Abstract: A sewing machine with a workpiece feed comprises a feed dog positioned below the workpiece providing a four-motion feed movement. A presser foot is fixed to a presser foot bar and can be raised from the workpiece during the stitching cycle by a lifting gear to ensure turning of the workpiece. This makes it possible to follow complicated seam patterns. The lifting gear is constructed in such a way that the presser foot is raised from the workpiece while the needle perforates the material, during its downwardly directed movement approximately up to its bottom dead center position.

Abstract: Method and device for safe operation of an automatic sewing machine having a programmable computer controlling a seam contour, at which a contoured workpiece clamp is automatically identified and compared with the sewing contour prior to the start of the sewing operation. The method also may include a further subroutine for automatically positioning the controlled seam contour with respect to the workpiece clamp so as to eliminate an accumulation of errors resulting in damaging of the automatic sewing machine. According to this invention a sewing head is provided with a sensor, which is moved along a distance limited by a firm reference point and a trigger point arranged at the workpiece clamp, where the detected distance corresponds to the profile of the workpiece clamp.

Abstract: A feed gear of a sewing machine for reversibly driving a rotary feed dog, as for example, a conveyor belt, a chain or a feed wheel, having a first gear part for producing an oscillating movement, and a second gear part for converting the oscillating movements into reversible intermittent rotary movements. The second gear part is provided with oppositely arranged driven one-way couplings.

Abstract: A computer-controlled automatic sewing machine has a sewing head and a workpiece holder. In order to be able to alternately sew at least two workpieces, the sewing head is movable in X and Y-directions by means of servomotors, while the workpiece holder having at least two workpiece clamps is fixed.

Abstract: A throat plate of an automatic sewing arrangement producing a double lockstitch and having a feeding device for generating a feed motion in any direction in a sewing plane as a relative movement between the needle and a workpiece. The throat plate is formed at the surface turned towards the workpiece with a closed needle aperture area, and is formed at the surface turned away from the workpiece with an opened needle aperture area profiled with a thread guiding edge affecting the hook thread leaving the double lockstitch hook. The thread guiding edge controls the position of the hook thread with respect to the needle so as to avoid a double interlocked stitch formation.

Abstract: A sewing machine has a feed for the workpiece which is to be sewn. A workpiece conveyor performs a skipping feed movement below the workpiece. Above the workpiece a turning device enables the workpiece to be turned about an axis which is coincident with the needle. In order to sew in an edge-parallel manner with an automatic guidance, workpieces made from soft materials with curved or angular seam courses, may be turned responsive to air nozzles directed in acutely-angled manner on to the supporting plate. The air nozzles are arranged tangentially, and in spaced manner, with respect to the needle.

Abstract: An arrangement increasing the rate of production and operating reliability of a method for identifying the type and/or size of a work receiving unit applied to an automatic sewing device. The identifying procedure is carried out prior to the sewing operation. According to the invention a sensor is associated with the sewing head or with the lower arm and provides a signal when coinciding with a mark at the work receiving unit. The sensor is first moved along a straight line in X-direction and then along a straight line in Y-direction. The straight lines each include a mark, one of which represents type of the work receiving unit and the other one the size of the same.

Abstract: A needle guard of a double lockstitch hook of a sewing machine in which the needle guard is fastened at the rotatably pivoted hook body and the free end of the needle guard rests on a supporting screw. By turning the screw the position of the needle guard with respect to the beak of the hook may be adjusted. The procedure of adjustment may be carried out under actual conditions without taking the hook out of the sewing machine.

Abstract: A method and a device for producing a pocket on a workpiece in which a pocket cut is folded at a margin of two lateral portions and one bottom portion connecting the lateral portions and attached by a stitch row to a workpiece. According to the invention, the folded pocket cut is additionally formed with folds situated in the lateral portions so as to manufacture extensible and spacious bellow-typed pockets. The device for producing such extensible pockets on workpieces is equipped with a workpiece folding device for folding the pocket according to the method described, a sewing machine and a control system for controlling a relative motion between the needle of the sewing machine and the workpiece and the folded pocket cut, so as to automatically perform a fastening stitch row according to a predetermined contour for attaching the folded pocket cut onto the workpiece.

Abstract: A workholder for a sewing machine for producing a stitch row in a workpiece according to a predetermined contour. The movably arranged workholder has a cutout essentially formed according to the stitch contour and is controlled with respect to the needle by means of a feeding device incorporating a linkage system and a control disc. In particular, a new frame-type workholder with an additional workpiece clamp is provided for rendering possible the production of a decorative stitch row in connection with a label fastening stitch row.

Abstract: An automatic sewing machine is provided with a workpiece feeding device for imparting a continuous motion to the workpiece during the sewing cycle and with a sewing head having a needle bar which is oscillatorily driven by an arm shaft via a crank gear. In order to reduce the needle deflection due to the continuous workpiece feed motion in a simple way, in addition to the crank gear for driving the needle bar, there is interposed a double crank gear between the arm shaft and the crank gear which reduces the angle of rotation while the needle penetrates the workpiece.

Abstract: In a sewing machine a workpiece feeding device having a lower feeding member intermittently and reversably driven and an upper feeding member in a steady contact with the workpiece and drivingly connected to the lower feeding member by means of connecting elements including one-way coupling means and a device arranged between the latter and the upper feeding member for interrupting or reversing the upper feed motion simultaneously when reversing the lower feeding member; different embodiments are described.

Abstract: A feeding device for an automatic sewing arrangement for producing a seam of a predetermined contour, in which a link system is provided with two levers and an output lever. To the free end of the output lever there is tiltably mounted a workpiece clamp. The two levers are pivotably supported about a stationary axis in order to be swingably driven. In order to allow universal displacement of the workpiece clamp, the displacement of which is only restricted by the size of the link system, driving devices engage independently from one another the levers. Furthermore, the workpiece clamp may be swingably driven by an electric motor.

Abstract: In a sewing machine a workpiece feeding device having a lower feeding member intermittently and reversably driven and an upper feeding member in a steady contact with the workpiece and drivingly connected to the lower feeding member by means of connecting elements including one-way coupling means and a device arranged between the latter and the upper feeding member for interrupting or reversing the upper feed motion simultaneously when reversing the lower feeding member; different embodiments are described.

Abstract: A control device for a differential feed system of a sewing machine in which a control box is connected to a control motor regulating the relation of the feed rates imparted to feed elements engaging a workpiece. The control motor is formed as a pneumatic cylinder composed of individual single acting cylinders arranged in a carrier tube is series, and is operably connected to the differential feed system including two independently adjustable feed mechanisms each regulated by such a pneumatic cylinder. Different feeding conditions for the workpiece, such as feeding the workpiece in a compressed, stretched or neutral relation at various stitch lengths, may be selected by the operator at the control box.

Abstract: A template for automatically topstitching joined and inverted workpiece parts on a sewing machine, in which the workpiece parts are clamped between two plates connected together by a hinge. The template is formed with guide grooves and tracks for the guiding and feeding elements of the sewing machine and provided in the area of the hinge with an opening for inserting the workpiece by a loading plate. When loading the template, positioning of the workpiece is eased by stops.

Abstract: A feeding device for an automatic sewing arrangement producing a stitch row according to a predetermined contour in a workpiece is installed with a linkage system having a control disc. The linkage system is provided with a workpiece clamping plate movably arranged in a plane and operably connected to the control disc. Furthermore, the workpiece clamping plate is movably received on a drive-off-lever of the linkage system. A linear drive with control elements is provided for displacing the workpiece clamping plate and locking the latter in at least two positions. Control means for at least interrupting the sewing operation during the displacement of the workpiece clamping plate are provided at the linkage system.

Abstract: A machine for sewing together two workpiece parts having edges of equal or unequal length by using a bead seam, especially for joining together the edge of a vamp and the shorter edge of a plug of a true moccasin shoe, so that the length of the plug matches that of the longer edge of the vamp, in only one operation. The bead seam forming device essentially consists of an auxiliary folding and ruffling finger acting in front of the needle of the sewing machine and in synchronous driving connection with the needle; several machines are described which are provided with different bead seam forming devices.

Abstract: A machine for sewing together two workpiece parts having edges of equal or unequal length by using a bead seam, especially for joining together the edge of a vamp and the shorter edge of a plug of a true moccasin shoe, so that the length of the plug matches that of the longer edge of the vamp, in only one operation. The bead seam forming device essentially consists of an auxiliary folding and ruffling finger acting in front of the needle of the sewing machine and in synchronous driving connection with the needle; several machines are described which are provided with different bead seam forming devices.