GB846275A - Improvements relating to the manufacture of curved tooth involute gears - Google Patents

Abstract

846,275. Gear-cutting or grinding; milling- cutters. INOUE, J. Aug. 2, 1956, No. 23898/56. Class 83 (3). [Also in Group XXIII] A machine for generating curved-tooth involute gears comprises a slotted controlmember 16 engaged by a crank-pin 5a at the projection of the generating point of a tool on the intersection of its periphery with the planeof-action 2, and a tool-head 27 on a carriage 15 sliding on a guide 14 parallel to the plane-ofaction in rolling contact with the base cylinder of the gear blank, the control bar being reciprocated and the gear blank being oscillated to generate the involute profile, and the toolhead being rotated so that the generating point follows an arc of a fixed circle 3 representing the curvature of the teeth. The tool may be a grinding-wheel of cup or pencil-type, or a cutter of face-mill, Fig. 4, or end-mill type, and the tool for the concave flanks may be of larger radius than that for the convex flanks to produce a crowning effect. A pair of cutters Ci, Co, Fig. 17, may be mounted eccentrically to cut both sides of a tooth simultaneously, or such cutters may be arranged to cut both sides of a space simultaneously. A grinding-wheel such as is described in Specification 846,276, may be used. The cutting-edges or faces of the tools may be slightly inclined, and adjustment for wear is provided. In Fig. 3, the wheel G is slidable along a guide 22 on the head 27, which is rotatable by worm-gearing 25, 26 about the axis 7, 7a of the circle 3. The head is connected to the slotted control-bar by the crank 5a. The bar is reciprocated by a cam 30 rotated by a main-shaft 32, which also rotates the worm 25. The bar and cam are held in contact by a weight 39 or by hydraulic means. A rack on the slide 15 rotates a pinion 35 to oscillate the gear-blank B through gearing 13.