GB485279A - Improvements in gear cutting tools - Google Patents

Abstract

485,279. Milling - cutters for gear-cutting. GLEASON WORKS. Dec. 16, 1937, No. 34898. Convention date, Jan. 15. [Class 83 (iii)] A face-mill gear-cutter particularly for cutting curved-tooth bevel or hypoid gears comprises a number of segments 16 each having several integral teeth 21 and being secured to a rotary head 15. The segments are of arcuate shape and have part-conical inner surfaces 22 and plane bottom surfaces 23. These surfaces fit respectively against a corresponding conical surface on the head and on a plane surface 27 at right-angles to the cutter axis. In Fig. 1 each tooth has an outside cutting-edge only, for finishing concave tooth sides, and the usual top and side clearances are provided. For locating the segments angularly, the head is provided with a number of slots 30 adapted to receive keys 35 which have plane sides which engage against the radial sides of the notches and serve as stops for engagement by the plane end surfaces 34 of the segments. The keys may be welded in position. Each segment is secured by a pair of bolts 40, the bolt holes 41 permitting slight angular adjustment of the segments, and tightening the bolts tends to draw the segment tightly against the seatings 25 and 27. A modification, Fig. 3, shows a single cycle cutter which finishes a previously roughed out tooth space, a gap A being provided in the cutter periphery to permit indexing when the gap is abreast of the blank. In this case, the successive teeth 56 ... 69 have alternating outside and inside finishing edges arranged to take successive cuts as shown in Fig. 9. The spaced cutters 70 and 71 mounted on a separate segment 511, take finishing cuts on opposite flanks. In some cases the cutters 68 and 69 may also be finishing cutters having edges at the same radial distances from the cutter axis as those of the teeth 70 and 71. The first segment 51a has only two teeth so as to provide a sufficiently large gap for indexing. In another modification the cutting segments may be secured to the inside surfaces of a head such as the outer cutter of a pair of eccentrically mounted face-mill cutters. In a further modification the locating ledge 26 may be provided on a separate plate secured to the cutter body.