Study On Reverse Design Of Logarithmic Spiral Bevel Gear

The design and manufacture of spiral bevel gears has played a veryimportant position in the machinery industry, spiral bevel gears in thetransmission process, the middle of the gear mesh at the helix angle of thedesign standards, while other parts are Approximation, strictly speaking,, cannot guarantee that the most reasonable from the principle of engagement.Therefore, the solution of the helix angle of the spiral bevel gear drive meshpoint are not equal it is very important. Spiral bevel gear, as a new form of geardrive, have more advantages than the traditional spiral bevel gears. Solve thestandard of the traditional spiral bevel gear tooth length direction of the helixangle approximation by characteristics of the logarithmic spiral and helix angle.Achieve implementation meshing of the helix angle.The tooth surfaces of spiral bevel gear is a complex shape of the spacesurface, leading to the processing is more difficulties than the average bevelgear. According to the generating method processing the logarithmic spiralbevel gear in the process. First according to the principle of developed into theparameters of the machining, processing a large gear, then according to theconjugate principle cutting the pinion. So, there are processing errors between the real processed tooth surface and the theoretical tooth surface of the spiralbevel gear, namely the deviation of tooth surface. In order to reduce the toothsurface error, must consistent make the actual processing tooth surface and thetheoretical tooth surface. Most economy applicable method is to collectdiscrete data points use of the laser scanning equipment, not only canreconstructed the tooth surface of spiral bevel gear, but also can make meshingpoint calculations between real tooth surface and theoretical tooth surface andmake difference surface analysis, and then get processing errors of the spiralbevel gear, to take further effective measures to improve the machiningaccuracy of the logarithmic spiral bevel gear.This subject used reverse engineering technology to do further studies ofspiral bevel gear by the logarithmic spiral bevel gears in kind, perfectingmeshing theory of spiral bevel gear theory.1. The reconstruction of the tooth surface of logarithmic spiral bevel gear.Scan the haved logarithmic spiral bevel gear by3D scanning devices,calculated the coordinate data of the discrete points of the tooth surface usedNURBS interpolation algorithm, first get the the cubic B-spline interpolationcurve tooth surface, will eventually be reconstructed the tooth surface oflogarithmic spiral bevel gear tooth surface by interpolation curve. 2. Error analysis of the structured tooth surface and the theoretical toothsurface of logarithmic spiral bevel gear. Based on the true tooth surfacemathematical model of logarithmic spiral bevel gears. The ultimate goal is tocompare the constructed tooth surface and the theoretical tooth face oflogarithmic spiral bevel gear, in order to calculate the error between them.Therefore, calculate a series of discrete data points according to have a truetooth surface equations of logarithmic spiral bevel gear, put the discrete datapoints into the theoretical equation of the logarithmic spiral gear, will be getthe corresponding data points. Final calculate the deviation of tooth surfaceaccording to the data point of the coordinates and the theoretical of the toothsurface, by the difference surface analysis tools, establish the differencesurface equation and correct machine adjustment parameters.