GB514113A - Tool for cutting curved tooth bevel gears continuously - Google Patents

Abstract

514,113. Milling-cutters. MAMMANO GEAR CO., Ltd., and MAMMANO, B. April 27, 1938, No. 12561. [Class 83 (iii)] A face milling - cutter for the continuous generating of curved-tooth bevel gears has finishing blades spaced at an' angle and within which are located subsidiary finishing blades, 'while roughing blades are arranged in the remaining angle of the tool face. In Fig. 1 the finishing blades V and Ware arranged at 180 degrees on the tool disc, a point E in the pitch plane and lying in the external edge of the blade V which finishes the surface A, B being at the same distance from the centre P as the corresponding point I in the internal edge of the cutter W which finishes the surface C, D. According to the invention the finishing blades Fi, Fe, Fig. 2, separated preferably by an angle a of 160 degrees in the case of the tool for cutting the pinion of a pair are associated with a number of other blades, all of the same rack section. For cutting the gear member, the finishing blades are arranged at 200 degrees, Fig. 3, on the tool disc, the sum of the angles between Fe and Fi on the two cutters being 360 degrees. The two cutters rotate in opposite directions for cutting the pinion and gear respectively, and by spacing the finishing blades. As described the tooth space cut is less than half the pitch on the pinion and correspondingly greater than half the pitch on the gear. Between the blades Fi and Fe are arranged a number of subsidiary blades S1, S2 &c. which cut on the -external edge and relieve the work of the finishing blade Fe. The sum of the radial differences in the settings of the blades S1 ... Fi is equal to the pitch thickness MN of the blades and the differences are graded to distribute the cut between the blades. The roughing blades R1, R2 &c. cut mainly on the internal edge and are set progressively at different heights. Fig. 7 of the drawings in the Provisional Specification shows the manner in which the blades a are adjusted to the desired radial settings, the screwed bush d being rotated after releasing the stamping bolt b. Formulae are given in the Specification for determining the settings of the roughing and finishing blades. Specification 465,008 is referred to.