Study On CNC Grinding Method And Equipment For Hardened Line Gear

Line gear is a new type of point contact gear which is designed according to the spatial conjugate curve meshing theory.It has the advantages of flexible design,minimum number of teeth can be 1,no undercutting,and easy miniaturization and light weight.It has a great application prospect in the field of light load and small and medium size mechanical transmission.After more than ten years of study,the line gear design theory has been gradually improved,and the related manufacturing technology has also made progress,but the related manufacturing technology is only in the rough processing stage.In order to further improve the load-carrying capacity,service life and transmission accuracy of line gear,the finishing technology of line gear must be studied.Based on the design theory of line gear,this paper studied the form grinding method of line gear.At the same time,according to the relative movement relationship between the grinding wheel and the line gear workpiece during the grinding process,a structural scheme of a special CNC gear grinding machine for line gear was proposed.The research in this article was of great significance for the development of the finishing technology of line gear,and also explored the way to expand the line gear market.The research content of this paper mainly includes the following four aspects.1.The tooth face equation of line gear was established.Based on the fact that the contact line of line gear was cylinder helix or cone helix,according to the parameter equation of cylinder helix and cone helix and the generating principle of tooth surface of line gear,the tooth surface equation and the normal vector of the points on the tooth surface of cylinder line gear and cone line gear are derived,and the tooth surface model of line gear was established by using Mathematica.2.A form grinding method of line gear was proposed.According to the generation characteristics of the tooth surface of the cylindrical line gear and the conical line gear,a form grinding method of line gear was analyzed,and the spatial coordinate relationship between line gear and form grinding wheel was established.The contact conditions between line gear and form grinding wheel in the process of form grinding are deduced,and the profile of the axial section of the form grinding wheel is calculated.3.A CNC grinding machine for line gear grinding was designed.According to the method of form grinding of line gear,the required motion of CNC line gear grinding machine is determined,the structure scheme of line gear grinding machine is proposed,and the type of grinding wheel to be used in the grinding process was selected.4.VERICUT simulation platform was used to simulate the form grinding process of line gear.The designed three-dimensional model of the CNC grinding machine for line gear and the NC program written according to line gear form grinding method were imported into the VERICUT simulation platform to perform grinding simulation on cylindrical line gear.Furthermore,the influence of the deviation of the form grinding wheel position on the tooth profile of the cylindrical line gear during the grinding process was analyzed,the results provide a reliable theoretical reference for the adjustment of form grinding wheel position parameters in the grinding process.