MACHINING OF TOOTH PROFILES ON CNC MACHINES

Abstract

Conventional methods of tooth machining using worm modular milling cutters, gear wheels and gear combs have common disadvantages - they require specialized equipment, are characterized by complex readjustment and relatively low productivity, which are eliminated in skiving. This paper views the possibilities for machining tooth profiles by means of skiving on CNC turning and milling machines. A new version of the kinematics of the process upon cutting inclined teeth has been implemented, where the feed is in the direction of the tooth, no correction in the angular speed is required and a skiving tool profiled according to the profile of the machined surface is used. Meshing of a tooth pair with crossed axes is reproduced. As a result of the crossing, slipping of the profiles occurs, which is the main cutting motion. The cutting speed, as a determining mode factor, can vary widely and depends on a number of design and technological parameters. Single-factor experiments have been conducted to determine the influence of the conditions of the implementation of the skiving process (the crossing angle of the tool axes and the workpiece, determining the magnitude of the cutting speed, and feed rate) on the quality parameters of the machined surfaces (tooth profile deviation, tooth direction deviation, accumulated pitch error, largest pitch difference and radial runout error) and the corresponding graphical dependencies have been constructed. A 7- 12 degree of accuracy of the machined tooth profiles has been ensured.