The Research Of Design Modeling And Error Detection Of Helical Non-Circular Gear

Non-circular gear has both the characteristics of gear and cam structure.Compared with the straight tooth non-circular gear,the helical non-circular gear has good meshing performance,smooth transmission,low noise,large coincidence degree and strong bearing capacity of the gear,so the helical non-circular gear has higher engineering application value.However,there is no perfect system and standard for the 3d modeling and precision measurement of helical non-circular gear at home and abroad,which limits the popularization and application of helical non-circular gear to some extent.Therefore,it is necessary to put forward the 3d modeling and precision detection method of helical non-circular gear based on the existing theory and technology.Based on the design theory of helical non-circular gear,the 3d modeling of helical non-circular gear is completed by using UG surface modeling module.The point cloud data of the actual model of helical non-circular gear is obtained by using3 d scanner,and the local point error is obtained by aligning with the theoretical model.The paper analyzes the errors of helical non-circular gear with gear error theory.Firstly,through the theory and specific requirements of helical non-circular gear,the parameter design and 3d modeling of helical non-circular gear are completed.In addition,the helical non-circular gear pair is analyzed by kinematics simulation experiment.The error terms can be measured for helical non circular gear.Secondly,point cloud data of helical non-circular gear solid model was obtained by 3d scanner,and the detection model was obtained by optimizing the point cloud data in the detection software.By aligning the detection model and CAD model in the detection software,3D detection and 2D detection can be carried out to obtain the deviation values of the specific detection coordinates,theoretical coordinates and normal direction.Finally,the tooth surface error of helical non-circular gear is evaluated by combining the detection data and the second order difference surface theory.The average pressure angle and the average spiral angle of helical non-circular gear were evaluated by combining the detection data with the first-order difference surface theory.The theoretical and actual coordinates are calculated by the method of infinitesimal method,and the cumulative error value of non-circular pitch of obliqueteeth is obtained.The tooth shape errors of different sections are analyzed and compared,and the average value is obtained to determine the final tooth shape errors.Based on the research of this subject,a new method is proposed to establish the3 d model of helical non-circular gear by using UG surface module.The computer aided detection technology is used to detect the errors of helical non-circular gear,which is more efficient than the traditional detection method,and provides a reference for the development and further popularization of helical non-circular gear.