Method of making barrel-shaped worm-like tool

Abstract

Provided is a method of making a barrel-shaped worm-like tool whereby a barrel-shaped worm-like tool capable of efficiently performing grinding without unequal wear can easily be made. The aforementioned method comprises making the barrel-shaped worm-like tool ( 12 ) by using a dressing gear ( 11 ) to dress the barrel-shaped worm-like tool ( 12 ), which is used for machining an internal gear and has a diameter that gradually increases from the ends ( 12 b, 12 c ) to the center ( 12 a ) in the axial direction. On the basis of data wherein the number of teeth is less than that of the internal gear to be machined, the dressing gear ( 11 ) and the barrel-shaped worm-like tool ( 12 ) are engaged with each other at the same axial intersection angle as during gear-machining performed by the barrel-shaped worm-like tool ( 12 ).

1 . A method of dressing a barrel-shaped worm tool that uses a dressing tool to dress the barrel-shaped worm tool, the barrel-shaped worm tool is used for gear-machining an internal gear to be machined by the barrel-shaped worm tool and has a diameter gradually increasing from ends in an axial direction to a center in the axial direction of the barrel-shaped worm tool, the dressing tool is a disk dresser of a shape in which a contour of the edge surface of the disk dresser matches a cross sectional shape of a tooth of the internal gear to be machined, the method comprising:
 determining dressing operation data based on the number of teeth for the barrel-shaped worm tool, which has a number of teeth that is smaller than the number of the teeth in specification data for the internal gear to be machined; engaging the disk dresser and the barrel-shaped worm tool with each other; and   moving the barrel-shaped worm tool and the disk dresser, in a state of engagement with each other, based on the dressing operation data.