METHOD OF THE LARGE-GRAIN TRACTION SPROCKETS GEARS WORKING Russian patent published in 2006 - IPC C21D9/32 C21D7/04 B23F5/12 

FIELD: mechanical engineering; working of various hardened details with alternating prominences and cavities.

SUBSTANCE: the invention is pertaining to the method of the large-grain traction sprockets gears working and may be used in various branches of engineering, in particular, for working of the various hardened details with alternating prominences and cavities. The working of the hardened gears by a superhard edge tool substitutes the cost intensive process of the gears grinding. The offered method includes the following set of the processes: existing traditional turning of a sprocket; the gears milling; the gears surface hardening up to HCR-51 hardness; the gears shaping by the edge tool; the final working - the surface plastic deformation of the whole working contour of the gears - the evolvents, as well as the junction curve and pits between the gears. At the edge tool working the uniform cutting off of the allowance in length (in height) of the gears takes place. Together with the metal cuttings all the defects gained after hardening are removed, and there is no inaccuracies on the worked surface, which may be observed after the gears grinding. At the gears lengthwise shaping there is the minimal facet pattern of 0.05-0.07 microns with the roughness along the whole length of the gears contour_{Ra = 1.2-1.4 microns, that ensures the suitable conditions for realization of the surface hardening operation. The applied method improves the quality and reliability of the gears operation and so promotes its implementation in the mechanical engineering enterprises and, in particular, at the railway transport repair enterprises.}

EFFECT: the invention makes it possible to substitute the cost intensive process of the gears grinding, ensures improved quality and reliability of the gears operation.