The Design And Study Of A New Type Crown Reducer Based On Nutation Drive

The transmission of the robot joint is mainly composed of harmonic reducer and RV reducer,domestic research on precision reducer of industrial robot is not mature,precision reducer is heavily dependent on imports,which restrict the development of domestic industrial robots,the key technology breakthrough of precision reducer is particularly important.In recent years,A new type of reducer based on nutation drive is emerging,the reducer has many advantages,such as,less parts,simple structure,large transmission ratio,more meshing teeth and great bearing capacity,which providing a new research direction for the robot.But the research on domestic reducer nutation drive are used inside and outside bevel gear as transmission gear,It is difficult to process bevel gears,which restricting the real application in the project.Therefore,this paper based on the principle of nutation drive,chose the coronary gear as the driving parts,completed the design and research of new type reducer.Based on the principle of nutation drive,this paper put forward three designs of reducer structure,and finally decided the main parts,including rotor gear,stator gear,elastic sheet,the input shaft and the output shaft by comparing and analyzing;decelerated the transmission ratio of the reducer;at the same time,because of the advantages of meshing teeth and meshing line contact,selected the crown gear as transmission parts of the reducer,and established the mathematical model of the crown gear meshing;studied the principle of tooth meshing through Rodrigo transformation matrix.The circular arc tooth profile engages a number of teeth,therefore,this paper selected the circular arc tooth profile as the basic tooth profile of the rotor gear,and the envelope of the rotor gear as the basic tooth profile of the stator gear;derived the tooth profile equation of rotor gear and stator gear;got the the coordinate file of tooth profile curve,and drew the profile curve by Matlab.Through calculation and analysis of gear tooth profile curve,studied the characteristic of crown gear based on nutation drive;derived the tooth force of crown gear;wrote a program to solve the related problems of the crown gear.Analyzed the effect of main structural parameters on crown gear tooth,such as,the nutation angle,pressure angle and the roller radius;analyzed the impact of transmission ratio and nutation angle on meshing efficiency of the crown gear;discussed the miniaturization of crown gear and provided a reference basis for the selection of structure parameters.This paper completed the 3D modeling of the reducer,and got the virtual prototype by Solidworks;analyzed the maximum deformation and stress of stator gear by Ansys,and verified the design of tooth profile meet the strength requirements;completed the motion simulation and dynamic simulation by Adams,and verified the accuracy of the driving principle and the feasibility of gear design.