Patent GB-190712689-A (GB)
Title: Improvements in and relating to Machines for Cutting the Teeth of Bevel Wheels.
Inventor: SUNDERLAND SAM
Filed: 1907-06-01
Granted: 1908-05-21
Abstract: 12,689. Sunderland, S. June 1. Shaping.-In a'shaping- machine for generating the teeth of bevel-wheels, in which the involute shape of the tooth is obtained by slowly rotating tbo blank and moving g a straight-sided cutter about the apex of the cone of the wheel, the teeth are relieved from their correct shape at the points as shown in Fig. 13. The work 8, Fig. 5, is mounted on a head 111 on a quadrant 43 and the tool 7 is reciprocated in guides on a vertical quadrant 3 rotatable about a boss 4. The teeth spaces are first roughed out by feeding the work up to the cutter by turning the quadrant 43 about its centre by means of a ratchet-operated rod 46, the work being automatically divided by dividing-apparatus 69 when the quadrant has been returned clear of the tool. When generating the curved sides of the teeth, the quadrant 3 is turned about its boss 4 and the work spindle is rotated by gearing from a belt-driven countershaft 17, the quadrant being driven by a toothed sector 3<A>, Fig. 3. The latter is not rigidly fixed to the quadrant but carries a block 105 fitting in an inclined groove on a slide 106 on the quadrant, a pin on which slide engages a cam-slot 108 in a fixed plate 109. In this way the motion of the quadrant loses or gains on that of the sector when the cam-slot is not circular and so the necessary relieving effect is obtained. The countershaft 17 drives through gearing a sleeve 22 ; this is clutched to a sleeve 23 provided with clutch teeth at each end, which drives the curvegenerating mechanism ; the sleeve 23 is driven for quick return by a clutch segment 36 on a shaft 24, adjustable cam-surfaces 39 on a disk 38 engaging stops 40, 41, Fig. 11, and reversing the driving of such sleeve as the disk rotates ; a triangular ring engaging spring-pressed pins 42, Fig. 5, assists in the closing of the clutches. The movement of the sector 43 is obtained from a rod 46 reciprocated by a disk crank 47, which while roughing the teeth carries a ratchet disk 60 and is driven by a pawl 56 from a cam 54 on a shaft 34, Fig. 11. When the disk has received a partial rotation in this way, a cam segment 60<A> on it operates a clutch 49 by which the disk is driven continuously for a halfrevolution and the clutch then is put out. When generating the teeth surfaces, the disk 60 is removed and the clutch 49 operated by a lever 74, operated through levers 76 by the projecting portion 39 on the sleeve 23. In generating one side of the teeth, the cutter starts at the point and works inwards, while in generating the other side it starts at the root and works outwards ; in the central position the cutter being moved to one side or the other of the centre of the roughed-out space. Dividing apparatus. - The dividing - apparatus consists of a dividing-wheel 69, Fig. 5, constantly urged by a friction-driven wheel 61, change gearing being provided so that the work is rotated through one tooth space for each revolution of the dividing- wheel. The dividing-wheel carries three stop pins 79, 80,81, Fig. 3, the positions of which are adjusted by a cam-plate on the wheel, such plate being connected with the wheel in one of three notches 86. One of these stops is engaged by a pin projecting through a fixed disk 91, such pin being withdrawn, as the sector 43 moves back from action, by engagement with a tippler plate on the frame of the machine, and allowing one revolution of the dividing-wheel. In roughing out the teeth, the centre stop pin 80 is used, while in generating one or the other side of the teeth the stop pin 79 or 81 is used.