Patent GB-316578-A (GB)
Title: Improvements in or relating to finishing gears
IPC: B23F19/02
Filed: 1929-07-17
Abstract: 316,578. Gleason Works, (Assignee of Slade, A. P.). July 31, 1928, [Convention date]. Gear wheels, grinding and trueing the teeth of ; spindles and spindle mountings.-In a method of finishing gears by burnishing or lapping, particularly bevel and hypoid gears, a pair of gears are rotated in meshing relation while simultaneously imparting to the gears a combined reciprocating movement longitudinally of the axis of one gear and a second movement transversely of this axis. The frame 20 carries a pair of heads 21, 22 which are movable at right angles to each other. The head 21 is adjustable on ways 30 by means of a, screw 24 which is rotated by a hand wheel 26 provided with a dial indicator 28. Locking of the head is effected by bolts 31, the two bolts being turned simultaneously by linkage 34, 36 operated by a hand lever. The pinion member 45 of the pair to be finished is carried on a spindle 44 mounted in ball bearings 42, 43 in the head 21. A spring 40, Fig. 15, is mounted behind a collar 39 on the spindly 24 thus holding the head resiliently in place and allowing the pinion to move away from its mating gear 68 to prevent breakage owing to too close engagement of the teeth. The head 22 is adjustable by a screw operated from a hand-wheel 51, locking being effected by bolts actuated by linkage similar to that provided for the bolts 31. A slide 54 is vertically adjustable on the head 22 by means of a screw 57 provided with a dial indicator 58. The slide 54 serves as a housing for a carrier 62 in which the spindle 63 of the making gear is eccentrically mounted in bearings 65, 66. Oscillatory movement is imparted to the carrier 62, soi that the gear 68 is moved bodily on an arcuate path to give component movements longitudinally of the pinion axis and transversely to this axis. Dust caps 71, 72 are provided tc prevent the lapping compound from reaching the bearings of the spindles 63, 44 respectively. For lapping operations, the pinion is preferably the driver, and the spindle 44 is rotated from an electric motor 73 by a belt 74. The gear 68 may be braked to increase the lapping action by means of brake arms 81, 82 acting on a drum 85 secured to the spindle 63. The arms are pivoted on a pin 80 mounted on a plate 76 to which the brake housing 77 is removably secured. The brake is manually applied by means of a handle 97 connected to a link 86 pivoted to the brake arm 82. Springs 93 - - 95 are provided to maintain the brake normally in an inoperative position. In addition to the hand brake a backlash brake is provided to take up backlash and to maintain at all times a moderate pressure between the gears. For this purpose the outer end 102 of the brake drum is fitted with a friction surface 103 engageable by a plate 111 which carries bolts 110 projecting through slots in a plate 106. This brake is normally kept in operation by springs 112 but by rotating the plate 106 the heads of the bolts 110 ride up a number of cam surfaces on the plate to withdraw the plate from the braking surface. For burnishing the drive is preferably imparted to the gear 68 and in this case the brakes are removed and a pulley driven from any source of power is mounted on the spindle 63. The oscillatory movement is imparted to the carrier 62 by means of a motor 121 geared to a slidable cam shaft 122 which carries a. disc 138 fitted on each side with a pair of cam plates 139, 140. One set of plates is used to finish the driving flangs and the other the trailing flanks of the teeth, the selection being made by axial movement of the cam shaft. The cams engage a roller 142 connected through a slide 143 and roller 144 to a lug 147 on the yoke member 148 which actuates the carrier. The cams 139, 140 are arranged to oscillate the carrier first in one direction and then in the other and are separated by concentric portions which allow the gears to run at certain parts of the cycle in their normal operative position. The driving mechanism is reversible in order to allow opposite sides of the teeth to be finished. Adjustment is provided to allow the axis of the gear spindle to be positioned at any part of the circle 162 described about the axis 161 of the carrier. As shown in Fig. 2, this adjustment permits variation between the proportions of the component F along the axis of the pinion and the component E in the transverse direction. In order to apply the invention to the finishing of hypoid gears wherein the axis of the pinion is offset from the gear axis, the gear spindle housing 54 is vertically adjusted on the head 22. For lapping gears a lapping compound of oil and abrasive is pumped from a reservoir 195 by a centrifugal pump driven by a motor 196, the compound being directed on to the gears through a nozzle 198. A trough 199 collects the compound which is returned to the reservoir through a pipe 200. When burnishing gears, the lapping compound may be replaced by lubricant, or instead of using the pump, lubricant may be applied with a brush. If the pinion is used as a driver, the backlash brake is preferably in operation, and pressure may be applied between the gears by bottoming the teeth of one gear into the spaces of the other. An automatic stop device may be employed to stop the machine after any number of rotations of the cam shaft. The stop control 210 may be actuated through a plunger 214 by a cam 215 and may operate through electrical connections on the motors 121, 73. A guard 220 is provided for the end of the pinion shaft 44. The cam shaft is similarly guarded at one end by the bearing 135 and at the other by a bracket 222. A pivoted guard 228, shown in its lowered position in Fig. 3, is provided for the gears under treatment. The gear shaft 63 is also guarded by a cap 224. The machine may also be used for testing purposes, the hand brake being used to apply load while running gears together to test their quietness and running qualities.