| Asymmetric gears are a kind of involute gears,which is mainly used in high bearing capacity occasions.At present,researchers mainly use wire cutting and EDM machining to manufacture asymmetric gear.Asymmetric gear used in high-load applications need to undergo a series process.Grinding is a essential process.According to the grinding tool,the tooth surface of the asymmetric gear and its meshing situation are deduced.Finally the machining verification is carried out.The main research contents of this paper are as follows:(1)The geometric parameters of asymmetric gears are studied,and the tooth surface equations of asymmetric gears,the tooth surface equations of tooth profile modification and tooth direction modification are deduced.The tooth surface equation of the rack tool,the coordinate transformation of the rack tool and the asymmetric gear and the meshing equation are established,and the asymmetric gear tooth surface is obtained.The tooth surface contact performance of the asymmetric gears with no modification,tooth profile modification and tooth direction modification is analyzed to provide a correct and reasonable tooth surface structure for the research of grinding processing methods.(2)Research on the processing principle and method of worm grinding wheel grinding asymmetric gears.The split diamond roller structure is designed,and the diamond roller dressing worm grinding wheel is deduced.According to the tooth surface of the worm grinding wheel,the coordinate transformation and meshing equation between the worm grinding wheel and the asymmetric gear is established,and the tooth surface equation of the asymmetric gear is obtained.The method of measuring the span of the asymmetric gear is studied,and the measuring formula of the span is given.Finally,the simulation is carried out in the Vericut software,and the three-dimensional tooth surface of the asymmetric gear processed by virtual simulation is obtained.(3)On the existing worm grinding wheel CNC gear grinding machine,the asymmetric gear grinding experiment was carried out.Modifying the installation method of diamond rollers can grind unmodified,tooth profile modified,tooth direction modified asymmetric gears,and introduce crossbar distance measurement in actual processing to check the grinding allowance of gears,and finally obtain complete grinding.Asymmetrical gears.The comparison between the measured three-dimensional space coordinates of the asymmetric gear grinding tooth surface and the theoretical tooth surface point coordinates shows that the maximum deviation of the gear processed by the grinding method given in the paper is 6 microns,and the accuracy reaches the 4th grade of the cylindrical gear.The thesis studies the method of asymmetric spur gear grinding.By transforming the existing worm wheel grinding machine,asymmetric gears with 4-level precision are ground,which solves the problem of asymmetric spur gear grinding. |
