Research On Digital Model Of Spiral Bevel Gear Based On Linear Approximation

Spiral bevel gear(called arc teeth or umbrella teeth)is widely used in aviation,vehicles and other power transmission because of its excellent transmission characteristics.Tooth surface modeling and CNC machining process of spiral bevel gear not only involves the forming principle,walking step,tool path,etc.,but also involves the coordinate transformation,meshing Theorem and other mathematical methods due to its tooth surface is the most complex surfaces among the gear type parts.Therefore,it is difficult to machine the spiral bevel gear applying CNC machining technology especially the high precision types by using general-purpose CNC machining equipment.At present,the method of obtaining high-precision spiral bevel gear and fine interpolation technology have become a hotspot in the field of numerical control machining.However,the practice shows that the method of fine interpolation has no engineering significance while machining accuracy reaches micron level.In this paper,approaches the spiral bevel gear teeth surface linear approximation technology based on OpenGL is proposed,aiming at processing trend of spiral bevel gear and the inadequacy of linear interpolation in CNC machining,combined with the unique advantages of the electrochemical finishing in enhancing the processing-quality and used performance.Key problems of CNC machining technology involved tool path and step length,furthermore the error is analyzed.Results shows that refining the step length is not the only way to fine interpolation technology,fine interpolation can also be achieved by changing the material removal method and can process higher machining quality parts,Using electrochemical finishing processing can make up for the inadequacy of linear interpolation.On this basis,the entity model of spiral bevel gear is constructed based on Linear approximation techniques of OpenGL and VC++6.0,in the meantime the error is discussed,this paper not only lays the foundation for accurate modeling and digital processing of spiral bevel gears and process the high quality,high precision spiral bevel gear,but also provides a new thought and method to expand and improve fine interpolation technology.