Sewing machine with rotationally driven upper advancement

摘要

The invention relates to a sewing machine with a rotatably driven upper feed system, the drive movement of which is derived from a drive shaft (1) via a clutch coupling. The clutch coupling essentially consists of a sleeve-like driving component (8) on the drive shaft (1) and a driven component (9) arranged coaxially therewith which drives the feed system (24) (Fig. 4), and a helical spring (7) providing the power connection between the two components which can be controlled via the axial movement of the changeover component (15). As the clutch coupling permits the transmission of forces in the axial direction, the feed system (24) arranged on the driven component (9) via the assembly (23) bears on the material to be sewn with a predetermined pressure even in the uncoupled position and is freely movable in both directions of rotation. The securing system of the assembly (23) on the material pressure rod (25) also facilitates the lifting of the feed system (24) off the material to be sewn.