GB637490A - Improved gear-wheel grinding-machine - Google Patents

Abstract

637,490. Gear-cutting. AEPPLI, A. Jan. 20, 1948, No. 1759. Convention date, Jan. 25, 1947. [Class 83 (iii)] [Also in Group XXIV] In a machine for generating gear-wheels by means of narrow-rimmed disc-like grinding- wheels 7, wherein the rolling movement is slow and the feed in the direction of the teeth is fast, the plane of each disc is slightly inclined to the direction of feed movement, and the spatial position of the feed-stroke is continuously displaced along the teeth in dependency on the rolling movement so that a strip of the entire length of the tooth-flank is ground in one feed-stroke. The slight inclination of each disc results in single-point contact between the disc and the tooth-flank and, according to the position of the path of the contact-point along the tooth-flank, so the actual path of the feed-stroke of the wheel is altered to ensure that minimum travel of the disc is required. In Fig. 9, the gear-wheel 6 is reciprocated past the discs 7 by a lever 10 actuated by a crank 14 and flexiblebands 12. The spatial position of the feed-path is adjusted by a cam 18 which is rotated by worm-gearing 19 and gradually alters the position of the crank 14 which is mounted, with its driving-motor, on a lever 15. The grinding- discs are carried on standards 21 secured to carriages 22 which are rectilinearly displaceable on sub-carriages 23 and are attached by flexible bands 25 to a central stationary cylinder 24. The sub-carriages 23 are rolled about the centre M by a fluid-operated rack 28 working through pinions 29, 27 and a rack 26 fast with each carriage 23, thus rolling the discs past the non-rotating gear 26 which is indexed after a rolling motion is completed. Bevelgearing 32, 33 rotates the worm-gearing 19, thus moving the path of the feed-stroke of the gear in dependency on the rolling-motion. The cam 18 may be theoretically exact or a straightline approximation. In a modification, Fig. 12, the spatial movement of the feed-stroke of the gear 106 is approximate, being effected by a sliding pin 142 which rotates a differential gear 145-147, to modify the position of reversal of a hydraulic valve 155. This latter valve controls the movements of a hydraulic piston reciprocating the gear-carriage 108 which is formed with a rack co-operating with a pinion on the end of a shaft carrying the valve-control disc 157. The feed-path may also be adjusted by mechanical stops or by movement of a switch controlling the reversal of a motor driving a feed-screw. Specification 15617/13, [Class 60], is referred to.