The Modeling Theory Of Accurate Spurs Gears Dies And Automatic Numerical Control Programmed By Figures Interactive Processing And Simulation

The extrusion technique become a trend towards spurs gears for it has many advantages, saving material, high productivity, high precision of parts dimensions, good parts surface and high product quality . But spurs gears have some difficulties in extrusion for they have no drawing slope. Stream surface outline can reduce the resistance pressure that produced by the objects going forward, so stream surface modeling become a new trend of modeling theory. This article leads stream function into computer aided design based on the theory, and to design an extrusion transition cavity to conform to the rule of metal flowing deformation, which can ensure the homogeneity of metal flowing, improve metal flowing properties, reduce product bending deflection and lower the extrusion pressure. It has a wide significance in gears extrusion.In this article, I do some work of mathematic model, geometric model, automatic NC programmed by figures interactive processing and NC process simulation. First, we realize the mathematic model through getting the parameterized equation by analyzing the fluid mechanics and make use of Bezier curve to approximate stream curve. In order to get the mathematic mode easily, we divide gear profile curve into five parts: the root of gear curve, the transition curve, the involutes curve, the transition round curve and the top of gear curve, which break the cavity into five surface parts. So we can describe the cavity by five groups parameterize equations. Second is geometric modeling, which can be established by the mathematic model with the help of Pro/ENGINEER. Last we realize the automatic NC programmed by figures interactive processing and NC process emulation by using the same software.This research job is the direction of modern CAD/CAM, and it plays a positive role in accurate spurs gears extrusion.