Study On Process Of Special-drive Curved Surface With Five-axis Milling And Optimization Of Technologic Parameters

Energy saving and high-precision of high-end Equipment put higher requirements to transmission accuracy of drive system forward. Ball spiral bevel gear is a key and essential component of internal drive system of high-end equipment. Inherent defect of cutting approach by Gleason restricts itself to improve machining and transmission accuracy. In order to break the existing cutting mechanism of spiral bevel gear and improve machining and transmission accuracy the author research five-axis CNC machining technology to ball spiral bevel curve. But non-uniform geometry characteristics of complex surface lead to time-varying characteristics of cutting area, which causes volatility of cutting force and affects the machining quality, tool life and machine vibration. So means to reduce the fluctuations of cutting force in order to improve the quality of such work pieces when the processing efficiency is improved is needed urgently in the curved surface processing field. This article breaking the traditional machining methods achieves a cutting method with five-axis CNC machine and establishes a new five-axis milling force prediction model based on the spindle speed and cutting area to complete optimization of machining parameters with spindle speed preferred under the influence of roughness. Details are in the following aspects.Firstly, according to the mathematical equations and the forming principle of ball spiral bevel gear the author completes parametric modeling of it accurately. Introduce the mathematical model of ball spiral bevel, add the parameters of gear, sweep tooth profiles, rotate and array them when modeling, the difficulties of which are sweeps and rotations. This article designs the machining tool path tangent to the driving surface in the machining module environment of UG. Then the tooth and the root surface uses different tools in according to the size of model. Five-axis machine completes the milling of the special-drive curved surface adapting machining parameters with spindle speed preferred and empirical depth of cut and feed rate.Secondly, this article simulates the five-axis processing by MATLAB after analyzing ball-cutter cutting conditions and researching on the equations of the ball-cutter edge. The author also calculates the range of contact area and cutting thickness according to the depth of cut, feed rate, geometry characteristics of special-drive curved surface, the equations of ball-cutter edge, and the mathematical model of cutting area cutting through the calculation of cutting thickness to the contact height. In order to measure at cutting force changes in data under different spindle speeds which can be used to conclude a new five-axis milling force prediction model with two parameters cutting area and spindle speed completely after filtered the author designs and machines an experimental carrier in which there are characteristics of the special-drive curved surface.Finally, with the spindle speed preferred, the author draws the best machining parameters by detecting surface roughness under different machining parameters which are used to full tooth cutting experiments with the five-axis machine tool. Machining results are proved to perform well after detecting gear precision, transmission accuracy and surface roughness.