Method of producing sewing machine needles

A method of producing sewing machine needles from a cylindrical length of wire by the steps of

• form pressing in which, starting from the cylindrical length of wire having a starting cross-section of a diameter substantially corresponding to the thickness of a needle butt, the length of wire is reduced approximately to a final cross sectional form over at least the entire length of a needle shank and by which in the region of the needle shank, a needle groove is pressed in from curved surfaces of the length of wire with production of a flat which projects on the surfaces as flat burrs on both sides, and wherein
• the pressing simultaneously presses a diameter reduction of the starting cross-section to a final diameter of the final cross sectional form of the needle shank and of a shoulder between the needle butt and the needle shank and to a needle point contour, so as to form the surfaces which have substantially the final diameter of the needle shank and respectively of the shoulder and of the point contour, and
• removing by stamping the flat which projects on the surfaces as flat burrs on both sides.

A method of producing sewing machine needles from a cylindrical length of wire by form pressing in which, starting from a length of wire of a diameter substantially corresponding to the thickness of a needle butt, the length of wire is reduced approximately to a final cross sectional form over at least the length of a needle shank and the length of a shoulder transition from the needle butt to the needle shank and grooves are pressed from a curved outer surface of the length of wire in the region of the needle shank, wherein

• the reduction in cross section is effected by pressing opposite wire material cross sections into laterally protruding flat burrs, leaving between the laterally protruding flat burrs outer surfaces of a transverse convex curvature defining a final diameter, and removing the flat burrs by a subsequent cutting,
• upon the pressing of the flat burrs a cross sectional profiling of the butt is pressed at the same time.

A method of producing sewing machine needles from a cylindrical length of wire sufficient to form a double needle blank by form pressing in which, starting from the length of wire of a diameter substantially corresponding to the thickness of a needle butt, the length of wire is reduced approximately to a final cross sectional form over at least the length of needle shanks and the length of shoulder transitions from the needle butt to the needle shanks and needle shank grooves are pressed from curved outer surfaces of the length of wire in the region of the needle shanks, wherein

• the reduction in cross section is effected by pressing opposite wire material cross sections into laterally protruding flat burrs, leaving between the laterally protruding flat burrs outer surfaces of a transverse convex curvature, and removing portions of the flat burrs by a subsequent cutting having an intermediate section thereof,
• after the removal of the portions of the flat burrs, and upon pressing of eye portions, pre-form pressing of needle points of two needles, with said points pointing toward each other with said intermediate section therebetween and a pressing of the needle shank grooves, laterally protruding burr-like shoulders ae pressed in regions of the points adjoining the intermediate section and throats are formed in the needle shanks.

A method of producing sewing machine needles from a cylindrical length of wire by form pressing in which, starting from a length of wire of a diameter substantially corresponding to the thickness of a needle butt, the length of wire is reduced approximately to a final cross sectional form over at least the length of a needle shank and the length of a shoulder transition from the needle butt to the needle shank and thread grooves are pressed from a curved outer surface of the length of wire in the region of the needle shank, wherein

• the reduction in cross section is effected by pressing opposite wire material cross sections into laterally protruding flat burrs, leaving between the laterally protruding flat burrs outer surfaces of a transverse convex curvature defining a final diameter, and removing the flat burrs by a subsequent cutting,
• two diametrically opposite vanes which remain as burr sections upon the removal of the flat burrs are formed at a transition region between the shoulder and the needle shank.