GB201207A - Improvements in gear cutting machines - Google Patents

Abstract

201,207. McLeod, R. J. March 30, 1922. Gear-cutting; tools.-In a gear-cutting machine three or more blank holding tables are arranged round a reciprocating cutting tool so that all the blanks are operated on during each cutting stroke. In the form shown the cutter, comprising a broach 1 made up of pinion-shaped form cutters, is mounted on a spindle 1<a> carried by a ram rotatably connected to a rack 8 reciprocated by a pinion 10 driven through belt and spur gearing from a main shaft 27. Reversal is effected by means of stops on a wheel 29 which act through lever mechanism and spring toggle device 37 to operate the beltshifting forks. The upper end of the cutter spindle and the ram 3 are mounted in guides 68, 4 respectively. The blank carrying tables 11, 12, 13 are supported on slides which may be fed along beds disposed radially of the cutter spindle by hand wheels 64. Automatic indexing of all the blank tables and of the cutter is effected during each return stroke through gearing actuated by a shaft 67 driven off the main shaft and connected through a clutch 39 and suitable spur and bevel gearing to worms 15, 16, 17 actuating dividing worm wheels on their respective tables. Change gears are embodied in the driving trains to vary the amount of the indexing movement of any or all of the tables as desired. The cutter is indexed by means of a worm 6 driven from a shaft 43a in the dividing train. The indexing movements are controlled by the clutch 39 which is engaged by means of a stop 33 on the wheel 29 acting through lever mechanism and spring toggle 40 and disengaged by a cam on a shaft 41. In a modification for cutting helical gears, the guide 4 comprises a cylinder having an internal guide coacting with a helical member on the ram 3 so that the cutter, the teeth of which are helically arranged, is oscillated about its axis during its reciprocation past the. blanks.