GB901416A - A cyclically-controlled sewing machine - Google Patents

Abstract

901,416. Sewing-machines. DURKOPPWERKE A.G. Jan. 12, 1961 [Feb. 19, 1960], No. 1293/61. Class 112. A cyclically-operated sewing machine comprising a resilient work-feeding clamp and a needle bar swinging transversely to the direction of work feed is provided with a bar pivotally mounted for movement towards and away from the needle, whereby a workpiece placed around the bar may be inserted in the clamp and upon operation of the machine the bar will serve as a guide for the workpiece. A feed bar 9, supported on the lower arm 2 of a sewing machine, carries at one end a pin 11 pivoted in a block 12 slidable in a groove 13 formed in one arm of a lever, the other arm of which carries a pin 16 which co-operates with a cam groove 17 in a rotary cam disc 6 to effect longitudinal movement of bar 9. To the other end of arm 9 is fixed a plate 10 carrying a block 20 embraced by a spring plate 22 which co-operates with plate 10 to form a resilient work clamp. A bar or plate 28, carried at one end of a two-armed lever 25 is adapted to enter the clamp. The other end co-operates with an adjustable stop screw 36 to regulate the extent of entry of plate 28. As shown, a workpiece 40, to which two strips 41, 42 are attached by a seam 43, is folded over plate 28 and the latter is moved within the work clamp. On operation of the machine the work is fed by the clamp and is guided on the plate 28, while the laterally-swinging needle 8 forms a line of blind stitching which does not appear on the inner surface of strip 42. An aperture 18 in plate 10 uncovers a numeral 1 on the throat plate 19 when plate 10 is at its extreme left-hand position, and uncovers a numeral 2 when plate 10 is at the extreme righthand position. Plate 28 is formed centrally with a needle-passing notch 30 and a line 31. The left-hand end of plate 28 is provided with two spaced lines 32, 32<1> and a numeral 1. The right-hand of plate 28 is provided with two spaced lines 33, 33<1> and a numeral 2. At the start of an operation if numeral 1 appears in aperture 18, one edge of the work is disposed to the left of line 31 and the other edge is disposed between the lines 32, 32<1>. If numeral 2 appears in aperture 18, one edge of the work is disposed to the right of line 31 and the other edge between the lines 33, 33<1>. In a modification, bar 9 makes two strokes per cycle, no stitching occurring during the return stroke, and the work-positioning numerals and lines are not provided.