GB338436A - A method or process and machine for cutting bevel or conical gears - Google Patents

Abstract

338,436. GÚny, A. J. Jan. 22, 1929, [Convention date]. Gear-cutting.-In cutting bevel gears by means of a cutter F, Fig. 4 having straight sided teeth arranged along part of a single turn of a helix and rotated continuously in timed relation with the blank, while it is fed along a generator of the blank root cone, the teeth are generated to correct involute profile by superposing on the blank rotation an oscillating rolling generating movement and simultaneously imparting the corresponding generating movement to the cutter, by oscillating it about the imaginary basic crown wheel axis during its feed movement. Equations are given in the Specification for determining the value of the angle #, Fig. 3, the pitch of the helix of the cutter teeth, and the pressure angle of the teeth. In a machine for carrying out the invention the guides 1 of the tool carriage are mounted on a rotatable head 2 and are pivoted at 2<a>. The oscillatory generating movement of the tool is effected by worm gearing 3 operated from a reversing mechanism 6. The blank table 4 is adjustable to the required cone angle about an axis 5<a> and is driven from a shaft 10 through differential gearing 9. The shaft of the worm 3 is connected through change gears 7 and worm gearing 8 to the casing of the differential, thus giving the required generating movement to the blank in unison with the tool head oscillations effected by the worm 3. The invention is also applicable to the cutting of helical bevel gears. Since a straight sided cutter is used, the same cutter may be employed to cut blanks having different extreme modules.