INTERNAL THREAD KNURLING METHOD Russian patent published in 2005 - IPC

FIELD: technological processes in machine engineering, shaping by plastic deforming of internal threads of large and mean sizes in parts of medium-ductile materials.

SUBSTANCE: method comprises steps of motion feed along worked surface of tool-head including housing with rod, at least three freely rotating thread knurling rollers arranged in forks placed in radial grooves of housing and designed for engaging with rod surface. Forks with thread knurling rollers are mounted with possibility of motion in radial direction by action of force applied to rod. In order to enhance efficiency, to improve accuracy and to lower cost price, thread knurling rollers are mounted in radial-thrust bearing assemblies on axles and they are fastened by means of nuts. Rod surface engaging with forks is cone one. Tool-head may be provided with two helical compression springs arranged in annular grooves of housing at side of ends of thread knurling rollers and used for providing constant engagement of forks with said cone surface of rod and preventing falling out of thread knurling rollers.

EFFECT: improved efficiency, enhanced accuracy, lowered cost price of thread knurling.

4 cl, 4 dwg