GB817627A - New and improved seam ripping device for sewing machines - Google Patents

Abstract

817,627. Sewing-machines. JECKER, G. [trading as JECKER LAURENZ SOHN, J.]. Sept. 30, 1957 [Oct. 6, 1956; July 2, 1957], No. 30595/57. Class 112 Cutting and severing work; presser feet. A seam ripping device comprises a knife fastened to the presser elements of a sewing machine in a position ahead of the presser feet on or closely above the throat plate of the machine and with its cutting edge directed against the cloth feeding direction. The knife a has a shoe b engaging the horns of the presser foot, the knife having prongs 2, 2<SP>1</SP> with a cutting edge 3 at their juction. The seam to be ripped is presented to the knife and fed past it by the feed means of the machine. In a modification the shoe b is adapted to engage one horn only, and the blade is inclined to the vertical. In a second embodiment the knife is integral with an angled plate one face of which has a slot to engage beneath the presser foot clamp screw, the edge of the knife lying horizontal. The knife, in a third embodiment (Fig. 9) is locked in a bore in a shoe b which is fitted under the presser foot c to contact the material of the work being ripped. A cross bar 16 and a strip spring 15 maintain the shoe in place . In a further embodiment a presser foot is provided to replace the usual foot, and has a hole in which the knife of the previous embodiment may be fitted.