Patent GB-191221308-A (GB)
Title: Improvements in and relating to Gear Cutting Machines.
Inventor: SUNDERLAND SAM
IPC: B23F1/06
Filed: 1912-09-19
Granted: 1913-09-18
Abstract: 21,308. Sunderland, S. Sept. 19. Gear - cutting. - Machines of the type described in Specification 21,225/08 are so arranged that the reciprocation of the blank slide is avoided by moving the cutter slide so that the cutter is brought into and out of engagement with the blank. Back - lash is taken up in the train controlling the generating motion before the cutter and blank are re-engaged, and a simplified indexing-mechanism is employed. The blank slide 2, Fig. 4, is adjusted on the bed, according to the blank diameter, by a screw 5 and is then clamped in position. The cutter slide 12, Fig. 3, is slotted to receive and is reciprocated by a crank-pin on a wheel 20 driven through the gearing shown from the pulley 14, and is mounted in a headstock 9 reciprocable to and from the blank in ways 8 on a saddle movable vertically for the generating motion on ways 6 on the frame and counterbalanced at 10. The index worm 80 is connected through change gearing 79, bevel gearing 76 and 74, Fig. 5, with a shaft 62 prevented from rotating reversely, to effect indexing, by a pawl and notched disk 83. The vertical motion of the saddle is obtained from a screw bevel-geared to a shaft 53, Fig. 4, changegeared to a shaft 51 spur-geared to a shaft 46 driven during cutting through clutch teeth 47, Fig. 6, by ratchet mechanism 45 actuated from the cutter-reciprocating mechanism at 40, Fig. 3. The shafts 51, 62 are connected by a ratchet clutch 64, Fig. 5. Long teeth on the clutch part 60 engage corresponding teeth on a clutch part 60<A> engaging a fixed sleeve 61, threaded to traverse the clutch part according to the direction of rotation of the shaft 51. When the saddle has been raised and the wheel blank rotated through the pitch required, a swivelling tappet 66 on the part 60<A> trips a lever system 67, 68, 69 allowing a clutch 26<A>, Fig. 7, to transmit drive from a pulley P, Fig. 3, through gearing 24 and shaft 25 to gearing 29, 30 operating a cam 36 and shaft 31 respectively. The trip mechanism is such that the clutch 26<A> drives for a complete revolution and the gearing such that the cam 36 makes half a revolution and the shaft 31 a whole revolution. The headstock is slotted to receive a crank-pin on a disk 33A geared at 33 to rotate through half a revolution for each complete revolution of the shaft 31. During cutting, the swivelling tappet 66 passes through the notch in the lever 67, and when the cutting is completed, the clutch part 60A brings the tappet under the projection 67<A> and trips the clutch 26. The clutch 48 is shifted to reverse the shafts 46, 51 and is maintained in this position by a detent 71 which is tripped when the projection 66<A> engages the projection 71<B>. A momentary reversal of the shafts then takes place to take up back-lash but the tappet 66 engaging the shoulder on the pivot side of the notch trips the clutch 26 again and stops the shafts 46, 51 during the return of the cutter slide to position to re-mesh with the blank. At the conclusion of this operation cutting proceeds as before.