| 摘要 |
560,781. Gear-cutting. COVENTRY GAUGE & TOOL CO., Ltd., and JELLIS, M. Aug. 14, 1942, No. 11378. [Class 83 (iii)] In grinding gear teeth by means of an abrasive hob 2 rotating in unison with the work 3 the work has an additional movement axially of the hob to distribute wear, compensating rotary movement being also imparted to the work, the axial and compensating movements being effected by means independent of the normal drive of the hob and work. In Fig. 1 the grinding hob spindle driven by a belt 7 or electric motor is connected through change gearing 12 to a shaft 17 carrying a splined worm 16 having bearings in a slide 21 which may be reciprocated by crank and connecting rod 26, 27 operated from a pulley 28 or by a motor. The worm 16 engages a worm wheel 18 on a spindle 19 connected by worm gearing 14, 15 to the work spindle 9. The latter is mounted in a head 10 slidable in a member 11. The head 10 may be moved to traverse the work axially of the hob by a point 23 engaging an adjustable sine-bar 24 on the slide 21, corresponding rotary movement being imparted to the work by the worm 16 moving over its worm wheel 18. In a modification, Fig. 3, the shaft 17 is connected through bevel gears 30 to a worm 16 engaging a worm wheel 18 on a spindle mounted in the sliding head 10, this spindle being connected through auxiliary change gears 34 to the spindle 19 driving the work. In this case the slide 10 is reciprocated by the crank 26 thus rolling the worm wheel on its worm to modify the work rotation in accordance with the traversing movement. 'The grinding wheel may be made as described in Specification 527,654 or 557,946, [both in Group XXIII], and the wheel head may be adjustable for helix angle. The wheel may be driven at reduced speed for dressing purposes. Means (not shown) may be provided for imparting axial feed to the work by a train from the gears 12. A depth of cut feed may also be provided. |
