GB1293412A - Improvements in or relating to cold rolling of gear tooth profiles on cylindrical workpieces - Google Patents

Abstract

1293412 Rolling gears MAAG GEAR WHEEL & MACHINE CO Ltd 14 Sept 1970 [16 Sept 1969] 43758/70 Heading B3M Teeth are cold rolled on to the surface of a cylindrical workpiece 1 by tools 40, the workpiece being reciprocated axially and the tools being rotated by a common drive. Additionally, in order to produce desired profiles/teeth in the workpiece, the workpiece can be rotated during its reciprocation, and each tool can be adjustably indexed radially of the workpiece, reciprocated axially and tilted. The workpiece is carried in a yoke 5, Fig. 1, which is reciprocated by a pivoted lever 18 coupled to a rocking lever 20. The lever 20 is rocked by a crank driven by a motor 31. The position of the central pivot for the lever 18 can be adjusted to vary the stroke and speed of the reciprocation. As the workpiece reciprocates, it can be rotatably indexed by means of a bush 11 coupled to it, the bush having helical splines 12 which co-operate with a collar 14. The bush can be exchanged for others having different splines, in order to produce a desired helix angle on the rolled profile. The helix angle can, however, be modified by rotating the collar 14 during rolling by means of a worm 87 and wheel 16. Additionally, the worm can be moved axially during each reciprocation of the yoke 5 by means of an adjustable assembly 131, so that each bush 11 can be used for a range of helix angles. A further lever assembly 147, together with a template 145, can be used to modify the rotational indexing of the workpiece at the ends of its stroke, when the tools engage and disengage the workpiece. Each tool 40, Fig. 2, is carried in a support 42 which is rotationally adjustable by a motor 141 in a support piston 44. The piston is movable axially during each workpiece reciprocation by a wedge 52. The wedge is biased downwardly by a piston 62 and is reciprocated by a driving-pin 64 and a lever 67. The lever is reciprocated by a rotatable cam 69 which is driven by the same drive as that which reciprocates the yoke 5. The cam is replaceable by alternative ones for varying the tool feed, e.g. a cam can be used for providing crown on a workpiece teeth or on two workpieces rolled simultaneously. The piston 44 can also be adjusted axially by a motor-driven worm 60. Each tool is rotated by gearing 102-108 which is coupled to the rotational drive of the worm 87 providing workpiece rotation. In addition to rotation, the tool can be axially reciprocated by means of a wedge 13 which co-operates, through bearings 112 and 110, with the end of the tool. The wedge is coupled by links 125, 124, 123 and 122 with a plate 119. The plate is connected to a slider plate attached to the yoke 5, the plate being rotatably adjustable so that a desired degree of reciprocation of the tools is generated during each reciprocation of the yoke. By aligning the plate axially with the workpiece, no tool reciprocation takes place. Two links 123 are so arranged that the axial movement of the piston 44 does not affect the operation of the assembly. A clutch 92, Fig. 1, is provided in the gearing which provides for rotation of the workpiece, the clutch serving to vary the feed according to whether pre-forming or finish rolling is taking place. The clutch connects either a worm 93 or a gear 90 to a shaft 91, thereby either keeping the casing 97 of a gear assembly 77 stationary, or rotating it.