Durkoppwerke Gmbh

Durkopp Adler Aktiengesellschaft

Kurt Biermann

Gerhard Steppat

Michael Rosemann

Wilhelm Stapel

Kurt Reinke

Klaus D Seiler

Bodo Wehmeyer

Hans R Goebbels

The presser device includes a feeder foot, a holding foot and a link transmission provided between the two feet, the two feet cooperating alternately. The feeder foot has a spur which cooperates temporarily with a mating surface on the cloth feeder. During the feed phase, the spur is obliquely inclined and does not press against the material being sewn, and therefore permits dependable ruffling of an upper layer of sewing material with respect to a lower layer of sewing material. At the start and at the end of the feed phase, the spur is vertically directed and presses against the sewing material, and thus smooth tension-ruffle-free sewing together, particularly of thin material, is made possible.

Top-feed sewing machine with presser device

A sewing machine has at least one rotating top thread hook, the hook enclosing a bobbin housing which accommodates a bottom thread. A spring bar is mounted in the base of the sewing machine and has a free end for bearing against the bobbin housing. The free end of the spring bar is displaceable by the top thread as it is being looped. To prevent unwanted displacement or oscillation of the spring bar, a cam is disposed in the base closely adjacent to the free end of the spring bar. The cam prevents displacement of the free end beyond a predetermined range of displacement.

Bobbin housing assembly in a sewing machine having at least one hook

A universal sewing foot, for a sewing machine having a skipping top transport and a skipping bottom transport, comprises an advancing foot and a holding foot which alternately engage the workpiece. A locking member selectively locks the holding foot so that it operates either in a non-skipping mode, in which the foot is urged downward against the workpiece by a spring, or a skipping mode, in which the foot is locked to the skipping upper transport with the spring under compression.

Universal sewing foot

A cutting device for cutting the thread chain, or the like, between successive sewn parts moving along a path through a sewing machine. The sewing machine includes a needle. A holder downstream of the needle includes a horizontal cutout. A hook for lifting the thread chain between adjacent sewn parts on the path is movable up through the cutout for raising the thread chain. A scissors moves across the sewn part path and cuts the upraised thread chain. The holder holds the upstream sewn part from shifting while permitting the downstream sewn part to shift slightly upstream as the hook rises and prior to the cutting, whereby a single cut cuts the thread chain adjacent both sewn parts. A sensor senses the trailing edge of a sewn part and activates a stitch counter to cause the needle to apply a predetermined number of stitches before halting sewing so that the cutting can thereafter take place.

Cutting device in a sewing machine for cutting at least one thread chain

A device for feeding to a sewing machine a strip of fabric, in particular a longitudinally folded band to serve as a pocket welt, comprises a generally oval-shaped guide mountable on the sewing-machine base and provided with sides shaped as U-profiles and with a tongue at an output end for folding a fabric strip upon passage thereof along a feed path to a sewing station at the machine. A beam of light from a gallium-arsenide source traverses the feed path in the region of the tongue to energize a photocell upon passage of a workpiece, the photocell being connected to a stitch counter for activating the same upon energization by the source. The guide has a length scale with graduations spaced in the direction of the feed path for implementing the manual positioning of a fabric strip prior to the feeding thereof to the sewing station, while the stitch counter is operationally coupled to the reciprocating sewing-needle drive to arrest the same upon counting a predetermined number of stitches. The positioning of a fabric strip via the scale and the automatic stopping of the sewing-machine drive by the photocell-activated counter ensure a precise positioning of a final stitch relative to a sewn welt.

Growing community of inventors

Bielefeld, Germany

Kurt Biermann