GB126291A - An Improved Method of and Tool for Continuously and Simultaneously Rough-cutting and Finishing of Gear-wheels according to the Rolling Principle. - Google Patents

Abstract

126,291. Wingqvist, E. H. April 29, 1918, [Convention date]. Gear-cutting; milling-cutters.-In cutting spur or bevel gear-wheels on the rolling generating principle, all the gaps are continuously rough cut and finished in a single continuous operation. As applied to the formation of teeth in which the line of intersection of the side surfaces of the teeth and the pitch surfaces form, when developed in a plane A, B, C, D, Fig. 1, congruous parts of parallel cycloids Z', Z<2>, the disk W, Figs. 11 and 12, carrying the cutters Sv, Sx for finishing the tooth surfaces is provided with cutters Fv and Fx to rough out the tooth spaces. If the blank H, Fig. 11, is rolled inwards relatively to the disk W, the cutter Fv which cuts with its outer corner is placed, so as to act first on the blank, at a radius R2 greater than the radius R, at which the cutter Fx acts, which in turn is greater than the radius R at which all the cutters Sv, Sx act. Figs. 11, 12, 13, 15, and 17 show different positions of cutter and blank, but at the same point in the feed, the finishing cutters not yet acting on the blank. Figs. 51, 53, 55, and 57 are similar views when the feed has advanced so that the finishing cutters only are acting on the blank. The angular position of the roughing-cutters Fv, Fx is chosen so that in their paths Z<4>, Z<3>, Fig. 1, they leave a minimum of metal to be removed by the finishing cutters. The number of roughing-cutters should be so chosen in relation to the number of teeth of the gear to be cut that the two numbers have no common factor, and thus all the gaps are acted on in succession, and the feed should be such that this is done by the roughing-cutters before the finishing-cutters begin to act. By using one or other of a pair of disks having 11 and 13 roughing cutters, all gears except that with 11 x 13, i.e. 143 teeth, can be cut. If the blank is rolled outwards, the radii R2, R, are made less than R.