Patent GB-236511-A (GB)
Title: Improvements in or relating to machines for producing toothed gears
IPC: B23F23/12
Filed: 1924-11-19
Abstract: 236,511. Gleason Works, (Assignees of Bullock, E. W., and Slade, A. P.). July 5, 1924, [Convention date]. Gear-cutting.-In a gear-generating machine for grinding curved tooth bevel gears the blank is rolled past an annular rotary grinding-tool which moves through a tooth space of the gear blank, the grinding-tool being intermittently withdrawn to permit indexing of the blank and being automatically dressed at predetermined intervals. The blank support is mounted in a head 5 on a table 6 which is angularly adjusted by rack and pinion gearing. The table is itself supported on a carrier 9 oscillated on ways 10 through a link 11 operated from a shaft 12. The translatory movement thus imparted to the blank is combined with a rotary movement to give correct rolling by means of a segment 13 rolling on a stationary segment comprising two portions 14, 15 which are slightly yieldable against the action of springs. The grinding-wheel 20 is mounted on a spindle 21, Fig. 43, journaled in a tapered bearing 190. a thrust bearing at 192 being adjusted by a nut 194. The sleeve 193 is held in its adjusted position by a locking-collar 195 and nut 196. The thrust bearing is surrounded bv an oil chamber 200 to which oil is supplied through a cup 201. The oil level is observed through a transparent closure 203. Cooling liquid is supplied to the grinding-wheel from a pump 216 driven by a belt, the fluid passing through pipes 215. 214 into a chamber 211 and thence to the interior of the grinding-wheel through openings 212. The inner surfaces of the grinding-wheel are coated with sulphur or other substance to prevent absorption of the cooling water. A modified construction of grinding- wheel is described. The support 22 of the grinding-wheel is moved intermittently after every fourth tooth-forming operation, whereupon the grinding surfaces are automatically trued in the manner described in Specification 236,523. The machine is driven from a motor 90, the belt 93 driving the grinding-wheel passing over tensioning-pulleys 94 mounted in a pivoted bracket 199 supported by a spring plunger 198. The motor shaft is connected through bevel gear 97, change gears 100 and worm gearing 101, to a cam-shaft 12. A cam wheel 38 is driven through a ring gear 104 and pinion 105 operated by two teeth on a wheel 106 secured to the cam-shaft which rotates once for every tooth cut, the gearing being arranged so that after cutting four teeth on the blank one of the cams 37 on the wheel 38 operates the mechanism for advancing and dressing the grinding-wheel. The grinding-wheel bed 2 is withdrawn from the blank to permit indexing by a cam 111 on the shaft 12. The cam 111 is provided with a switch device operating as described in Specification 236,522, the grinding- wheel being automatically withdrawn and the machine stopped on completion of the blank. The indexing mechanism is provided with means for independently adjusting the blank and index wheel with reference to the rolling mechanism. A pivoted lever 171 held by a plunger 172 carries a slide 174 provided with a locking-dog 175 engaging the index wheel 176. The slide 174 is held in adjusted position by bolts 177, and on loosening these bolts the slide 174 may be manually operated by worm gearing 178 and carries with it the locking dog, index wheel, and blank spindle.