Method, tool and device for the production of threads

Abstract

A method for the production of threads, especially internal threads, by means of a rotationally driven thread former, with which the thread pitches are driven in and out of the surface of the workpiece in a chipless fashion by pressure forming, in particular in and out of the inner surface of a workpiece bore. In order to be able to produce threads of different nominal diameter especially economically and with improved joining quality in the area of the thread, the thread is formed such that a shank tool in the fashion of a thread miller, equipped with at least one profile projection, preferably two profile projections located at a constant distance from one another, where the profile projections at its forming head are constructed as continuous over the circumference and with radial extension varying over the circumference, is driven into the workpiece initially at a circumferential point of the workpiece bore, preferably is brought to the total thread pressing depth, and while substantially retaining the eccentricity set with respect to the axis of the workpiece bore, executes a relative circular movement running through 360° (circular movement) relative to the axis of the tool bore, while the forming head simultaneously executes a constant axial relative feed movement by the extent of the thread pitch to be produced.

Dependencies are inferred from the claim text.