GB589246A - Improvements in or relating to the production of gear teeth - Google Patents

Abstract

589,246. Gear-cutting. McLEOD, R. J. Nov. 7, 1944, No. 21843. [Class 83 (iii)] In finishing toothed gears by shaving with an intermeshing generator cutter, the work U is rotated slowly on a stationary axis by an electric motor M and change gearing and coaxial freerunning cutters 12, 13 are rotated by the work on a parallel axis on a slide 4 which is reciprocated rapidly parallel to the cutter axis by an adjustable throw crank C driven by change gearing C' and an electric motor D. The cutters have serrations forming cutting edges extending from the root to the tip of each tooth and have the same helical angle as the work and the reciprocations do not disengage the cutters from the ends of the teeth on the work. The saddle 1 carrying the slide 4 is adjusted to and from the work on the bed 2 by means of a hand- or power-operated screw. Each cutter head 7, 8 is adjustably secured to the slide 4 by T-slots 6, Fig. 6, and bolts 11 and has a recess 7<1> to receive a block 16 provided with plain bearings, or the roller and ball thrust bearings shown in Fig. 5, for the cutter spindle 14. A wedge 20 in a slot in the block is slidable on a pin 21 secured to the head and is movable to adjust the cutter by means of a nut 23 and screw 24 rotatable by a worm-wheel 25 and a worm 26 on a shaft 27 mounted on the slide 4. The shaft 27, which is rotatable by hand, is formed in two parts joined by a toothed clutch 29 so that by disengaging the clutch one cutter may be adjusted relatively to the other. If one turn of shaft 27 moves the cutters by 0.001 inch, ten teeth in the clutch will allow relative adjustment of the cutters by 0.0001 inch. Each cutter head 7, 8 is adjusted on the slide 4 by a hand-operated screw 9. The machine may be arranged with the work axis vertical and the slide 4 and work rotation may be actuated from a common drive.