Sewing machine with upper and lower workpiece transporters
AssigneeDurkoppwerke GmbH
InventorFranz Hanneman
Life of this patent
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Abstract
A sewing machine designed to stitch together two stacked fabric layers advancing at different speeds comprises an upper and a lower conveyor belt coupled with a common drive shaft by a differential gearing. The relative speed of the two conveyor belts can be manually adjusted with the aid of a friction coupling comprising two mutually parallel larger disks with relatively offset axes and overlapping surface areas contacted by a smaller disk perpendicular thereto, the latter disk being displaceable in a common axial plane of the two larger disks to vary their transmission ratio.
Claims5
In a sewing machine having transport means for moving two stacked workpiece layers at relatively variable rates past a vertically reciprocating needle adapted to stitch them together,
- the improvement wherein said transport means comprises an upper conveyor belt and a lower conveyor belt with parallel horizontal runs aligned to advance said layers between them, drive means for actuating said conveyor belts with codirectional displacement of said horizontal runs, and adjustable transmission means between said drive means and said conveyor belts for varying the relative rate of displacement of said horizontal runs.
Dependencies are inferred from the claim text.