Abstract: A workpiece transporter for a sewing machine comprises an endless conveyor belt looped around a driving sheave and several deflecting rollers, the latter including a first and a second roller carried on the free ends of respective spring-loaded levers placing that belt only under a moderate tension. The first deflecting roller is closely juxtaposed with the upstream side of the driving sheave, its axis defining with that of the sheave and with the fulcrum of its lever an obtuse triangle whose vertex angle increases as that roller approaches the sheave when an obstacle retards the belt motion, such approach clamping the belt more tightly between the roller and the sheave for firmer entrainment.

Abstract: To grip the tail end of a workpiece such as a stack of fabric layers to be stitched in a sewing machine, a pneumatically actuatable clamp on a carriage reciprocably guided along a rail has an air inlet in the form of a first nipple with a lateral entrance aperture confronting a discharge opening of a stationary air-supply line when the clamp is in a retracted loading position remote from the sewing machine. Air admitted in that position to a pressure cylinder via a branch of the supply line forces the inlet duct of the clamp against a sealing ring surrounding the discharge opening to conduct the main air flow via a check valve and a control valve to an operating jack for closing the clamp, the jack including a single-acting spring-loaded piston.

Abstract: A system for the edge-parallel sewing of a workpiece, consisting of a plurality of layers, together to form a seam, e.g. in the production of trouser legs, pockets, shirts and the like, comprises a workpiece guide in the region of the needle path and formed with separators interposed between the layers, and a drag-clamping device which engages a portion of the stack of fabric layers remote from the incipient stitching operation to apply a stretching or drag force thereto. According to the invention, a retracting device is provided which, upon approach of the drag clamp to the stitching location, withdraws the guide device out of the path of the clamp.

Abstract: A sewing station in which lengthy material, e.g. sleeve or trouser-leg fabric workpieces, can be provided with a seam in substantially automated operation. The material to be sewn is advanced from a loading station, where it is initially held by a fixed clamp, to the sewing machine. While the material is advanced past the sewing machine by the fabric transport, it is guided by a moving or trailing clamp which trails along with the material holding it in lightly stretched relation to the sewing machine transport mechanism. The clamps are provided with pneumatic pistons which actuate or perform the clamping functions. The pistons are controlled by switches and valves to alternatingly open and close the clamps as required by the seaming operation. The station provides for a simplified operation requiring monitoring by an operator only for the initial positioning and initial seaming.

Abstract: A feed device for flexible workpieces comprises a clamp for securing two workpieces together. The clamp is movable along a guide in line with the displacement of the workpieces past a sewing station by the sewing machine feed. A retarding force is continuously applied to the clamp to maintain a tension on the workpieces as they are drawn through the sewing station preferably by a turbine driven by compressed air. The retarding force is a continuously applied restoring force which can be switched between a relatively substantial force designed to return the clamp to its starting position and a tension force which can be reduced to substantially a zero value.

Abstract: A pair of tracks are pivotal and alignable with a stitching station of a sewing machine. Carried on each track is a clip which is normally biased away from the sewing machine but displaceable against the biasing force toward the stitching station. Each clip has a lower jaw swingable between an upper operative position and a lower return position and an upper jaw pivoted on the lower jaw and swingable between an upper open position, a lower operative position, and a third return position. In the return positions both of the jaws are below the plane of the support table adjacent the sewing machine. The trailing edge of a workpiece is clipped in one clip and the leading edge of the workpiece is fitted to the sewing station. As the clip approaches the sewing station it first automatically opens, then is automatically swung into the return position so that a workpiece whose trailing edge is held in the other clip can then pass over the returning clip to the sewing station.