Patent GB-701138-A (GB)
Title: Milling and boring machine for gear-cutting operations
IPC: B23F5/22
Filed: 1952-01-03
Abstract: 701,138. Boring and turning mills; gear-cutting. SOC. NOUVELLE DE CONSTRUCTION DE MACHINES-OUTILS ET D'OUTILLAGE PROCEDES C.W.B. Jan. 3, 1952 [Feb. 17, 1951], No. 261/52. Class 83 (3) A milling and boring machine having a horizontal rotary work-table 9 comprises a detachable cutter-head 12 on the machine headstock 6 and fitted with a cutter-carrying arbor 28 rotatably driven from the machine spindle 7 for cutting a gear-blank 11 clamped on the table. The machine has an axially-adjustable boring-head 6 on a vertically-adjustable slide 5 on a column 3 sliding on ways 2. The cutter-head 12 is carried by a support 13 and is angularly adjusted about the axis of the spindle 7, according to the helix angles of the gear and cutter, by a worm 18 carrying a squared end 21. The angle to which the head is adjusted is indicated in degrees on a scale 22 and in minutes on a scale associated with the squared end 21. The cutter shaft is mounted in axially-adjustable bearings 29, 30 on the head 12 and is rotated through gearing 34, 35 by a worm 37 on the machine spindle 7. The spindle 7 is rotated by a motor on the head 6, Which motor may also rotate the work according to the setting of a dutch 48. When cutting plain spur gears by a hob 27, the work-table is connected to the motor driving the spindle 7 through a spindle 49, gears 51, 54, 56, 58, a shaft 59, a vertical splined shaft 67, worm gearing 71, and gears 74 ... 76, the latter being clutched to the spindle. The slide 5 is given a vertical feed motion as the cutter and blank rotate. The hob 27 may be replaced by a form-cutter and the drive to the table 9 omitted. When it is desired to hob helical spur gears, the gear 76 is unclutched to rotate freely on the spindle 7, and its rotation is imparted through differential gearing 79, 81 to a gear 83 fast on the spindle. To compensate for the downward feed of the hob, an additional motion is imparted to the differential gearing by the motor 103 which rotates the feed-nut 100 of the headstock slide 5. The motion is transmitted through a clutch 94 which is disengaged when plain spur gears are cut. Cutting worm-wheels.-In a modification, a cutter-head is provided with a taper hob 110, Fig. 8, or fly-cutter to cut worm-wheels. In this case, the cutter 110 is carried on a slide 109 bearing a rack 115 engaged by a worm 118 rotated through gears 122, 123, 125 and shafts 126, 128 connected by a clutch 127, the shaft 128 being driven by a separate motor, not shown, for moving the hob tangentially. The spindle motor rotates the table 9 through the gear 83 fast on the spindle 7 and the gear 76, differential gearing 133, 131 being interposed to compensate for longitudinal feed of the hob 110. Form-cutting.-For form-cutting internal spur gears a head 137, Fig. 9, is provided. If the gears are helical, means are provided to rotate the table in relation to the vertical feed of the cutter. In a further modification, a conventional form-cutter replaces the end-mill 138 of the previous embodiment and permits the cutting of straight toothed internal spur gears. When formcutting, the table is indexed by a feed motor 47 acting through the clutch 48, or by a motor 44 which normally rotates the table 9 through a clutch 45 for vertical turning operations.