GB1334966A - Control of tooth flank grinding machines for helical gears - Google Patents

Abstract

1334966 Machine tool details MAAG GEAR WHEEL & MACHINE CO Ltd 7 Oct 1971 [16 Get 1970] 46741/71 Headings B3B and B3K In a tooth flank grinding machine in which helical gears are operated on by an indexing generating method, the grinding stroke is controlled by stops so that the stroke is at a minimum at the beginning of the traverse, at a maximum in a central region of the traverse, and is then reduced at the end of the traverse. The machine comprises a platen 2 slidable on a base 1, a column slidable transversely on the platen, a pivotable plate 4 for adjusting the helix, a ram 5 on plate 4 for adjusting the discshaped grinding wheels 6, 7, and a rotatable work-table 10. Grinding wheels 6, 7 are driven by separate motors 9. Column 3 is traversed by a motor 15 through gearing and clutch drive 16-40, and a lead-screw and nut 41, 42. Table 11 is also rotated by motor 15 through gearing 16-26, 43, clutch 44, and change gears 47-50, and a worm drive 14. The tangential motion of column 3 is matched to the rotation of workpiece 12 by change gears 30-33, and 47-50, thus producing the generating motion between the grinding wheels 6, 7, and workpiece 12. The path of travel of the gear-wheels is reduced to the area A 1 , B, B 1 , C 1 , D, D 1 . The stroke is controlled by a control unit 52, Fig. 4, which comprises a switch 53 mounted on a nut reciprocated along a spindle 55, in synchronism with the motion of grinding wheels 6, 7. Spindle 55 is coupled through bevel gears 56, 57, to a shaft 58 which is coupled through bevel gears 59, 60, in the centre of plate 4, to a shaft 61 driven by a ram spindle 64 through bevel gears 62, 63, spindle 64 being driven through a worm and wheel drive 65, 66, by a reversing motor 68, which reciprocates the grinding wheels. Unit 52 also comprises a horizontally slidable plate 70, to which is connected a wire rope 69 which passes over a pulley 71. A second rope passes from a second pulley 72 to a smaller pulley 74, which is supported, along with an integral larger pulley 75, in column 3. A third rope passes from pulley 75 to a block 77 on platen 2. The pulleys function as a reduction transmission. Two control rails 79, 80, on plate 70, coact with switch 53, and a shaft 81 drives a screwed spindle 85 which is screwed into a nut 86 carrying a switch 87. Opposite end limiting stops 88, 89 are provided for switch 87. The area of traverse is controlled by switches 53, 87, stops 88, 89, and control rails 79, 80. The generating speed is determined by the speed of motor 15 which is controlled by a potentiometer 91, Fig. 4, actuated by cams 92, 93.