Tooth Profile Error Analysis And Dressing Of ZK Worm

ZK worm is a kind of new-type worm, which is a conical envelope worm, and it can be grinded by conical wheel directly, with simple grinding technology and high tooth profile accuracy, so its machinability is good. Tooth profile error exists with the decreasing of radius of conical wheel during grinding process. Study on tooth profile error as a result of radius changes of conical wheel is rarely few at home and abroad, which influences the development of ZK worm, and deeply study is necessary.Background of ZK worm studies at home and abroad is demonstrated in the paper, and the importance of this subject is illustrated. The main contents of this paper were presented as follows.At first, the wheel model which involves several dressing parameters is presented, the tooth surface equation and the profile equation is deduced using spatial meshing theory, theoretical tooth profile and normal profile angle are calculated using numerical calculating method by VB language, axial profile is drawn automatically.Secondly, ZK worm model is machined using the wheel model which involves several dressing parameters, the optimal dressed profile of grinding wheel is gained by optimizing the wheel dressing parameters, which decreases tooth profile error as a result of the decreasing of conical wheel radius, and the service life of the wheel is prolonged.Lastly, simulation machining of ZK worm is carried out on the basis of the fact that the accuracy of AutoCAD software boolean operation can contented the requirement of simulation machining error. The correctness of mathematical model of ZK worm and the calculated results is valid by compares of simulated tooth profile and theoretical calculated tooth profile.