SELF-OPENING THREAD-KNURLING HEAD

FIELD: manufacturing processes in machine engineering, namely by plastic working of metals, particularly making tools for forming outer threads by plastic deforming-knurling. ^ SUBSTANCE: head includes body and stem. Body may perform free rotation in stem and it has on inner surface of its opening portion with left-hand thread and portion with right-hand thread. Disc is arranged in each of said portions; discs have inner cone surfaces and radial grooves. Discs are movably joined with stem through pins. Head includes at least three thread knurling rollers that may perform radial motion, are mounted on axles in needle type bearing assemblies and fastened by means of nut through rings with cone outer surfaces engaged with said inner cone surfaces of discs. Head is provided with thrust bearing assemblies arranged at end sides of rollers. Axles are arranged in said radial grooves of discs and they are subjected to action of springy rings rested upon pins. ^ EFFECT: simplified design, possibility for knurling high-quality threads in wide range of diameters and pitches at improved efficiency. ^ 4 cl, 5 dwg, 1 ex