Measurement And Error Analysis For Loxodrome Normal Circular-arc Spiral Bevel Gear

This work is one branch of the project named The Theory and New Type Transmission Pair Based on Bertrand Surface (No. 50275017), which is supported by National Science Foundation of China. In this dissertation, the relationship between the errors and variations for the loxodrome normal circular-arc spiral bevel gear (LNCSBG) is deeply studied. Another main content of this dissertation is geometric error measurement.The reports for the relationship and the error definitions of the new type gear haven't been found. This paper gives the equation of conjugate gear pair, the relationship equation between errors and variations, the equation of susceptibility and so on. The table of susceptibility is given based on the parameters of the LNCSBG. As a conclusion, the gear pair is deeply effected by the shaft angle error. And this paper defines the related errors of the LNCSBG according to the table.The special measuring machine for evaluating the new gear isn't designed, so we take the method of coordinate measuring machine (CMM) and mainly evaluate the tooth profile error and tooth trace error. On the grounds of CMM, the project for measuring the gear is established. And the data are got from the experiment. The paper mainly studies in theory the transform relationship between the designed coordinates and measurement coordinates and the mathematical models of correspondence parameters of gear surface. In the course of solving the problems of models, the method to solve normal of tooth surface is presented by fitting the hyperbolic paraboloid. And the interative algorithm of nonlinear least square is got. The models are proved effective and practical by experiments.