SETT ATT FORMA EN ENTRINGSDEL PA ETT CYLINDRISKT SKRUVEMNE SAMT ANORDNING FOR GENOMFORANDE AV SETTET

摘要

The present invention relates generally to improvements in methods and mechanisms for swaging the entering portion of a screw blank, and more specifically to novel methods and mechanisms for producing screw blanks having laterally offset, substantially conical entering or work swaging portions and a pilot extending therefrom. The invention as disclosed herein contemplates the use of a novel die arrangement wherein a first die section is provided with an openended cylindrical bore for telescopically accommodating a screw blank of corresponding size. An adjacently positioned second die section having a substantially conical bore is adapted to receive the entering extremity of a screw blank from the first die section. The substantially conical bore has a peripheral surface comprised of a pair of segments of conical surfaces each generated from axes which are offset or laterally displaced and one of these axes being coincident with the axis of the bore in the first die section. This second die section is positioned intermediate the first die section and a third die section having a pilot-forming bore the central axis of which is coincident with the bore of the first die section.