Design And Research Of A New Type Of Precision Cycloid Reducer

At present,RV reducer and harmonic reducer are the main precision reducers used in industrial robots at home and abroad.RV reducer has high loading capacity,but because of the limitation of transmission principle and structure,its outer diameter size is larger than 120mm,which makes it difficult to achieve miniaturization.Harmonic reducer can achieve miniaturization design,but its loading capacity and impact resistance are relatively poor.In this regard,a new type of precision cycloid pinwheel reducer is proposed.The reducer can realize the miniaturization of the structure size and has a high loading capacityThe main work is as follows:The shape and size of the reducer refer to the CSG-14-50 type harmonic reducer of Harmonic Drive Company of Japan.The outer diameter of the reducer is 56 mmIn the design process of reducer structure,the principle of precise cycloidal transmission is analyzed.A mathematical model of cycloidal gear profile is established for its core component cycloidal wheel.Considering the manufacturing error,good lubrication in the continuous transmission process and convenient disassembly and maintenance of reducer,a combined modification square of cycloidal gear profile is put forward based on the theory of optimum modification.The formula for calculating the initial clearance caused by the modification scheme is derived.According to the design parameters of cycloidal gear profile and the corresponding optimum modification quantity,the meshing force between standard cycloidal gear and standard pinwheel is calculated.Based on iteration method,the meshing force of modified precision cycloidal transmission is calculated by using MATLAB software.The maximum contact stress of modified cycloidal gear tooth surface is checked by Hertz formula,and the design parameters meet the requirements of reducer bearing.Load capacity requirements.By analyzing the advantages and disadvantages of different types of reducer output mechanism,a new type of disc output mechanism with cross-groove is proposed.The output mechanism can transfer pure torque,has strong bearing capacity,compact structure and simple manufacturing.The configuration scheme of crankshaft arm bearing is put forward.According to the actual load of the arm bearing,the service life of the arm bearing is checked.The configuration scheme of 45 degree cross roller bearing between reducer output terminal and housing is proposed.This scheme can improve the anti-overturning ability of output terminal under the condition of guaranteeing output torque.Finally,the overall structure of the reducer is put forward,and the three-dimensional model of the parts and assembly of the reducer is established by using Solidworks software.Using Solidworks Simulation finite element analysis software,the static analysis of the precision cycloidal transmission part after modification is carried out,and the stress,strain and displacement nephograms of the modified cycloidal gear are obtained.The maximum contact stress of the tooth surface of the cycloidal gear shown by the stress nephogram is very close to the theoretical calculation results,which verifies the correctness of the cycloidal pinwheel meshing model.According to the constraints of crankshaft,cycloid wheel and cross groove disc in the actual working process,the modal analysis of the three key components is carried out by using finite element analysis software.The first six modes of each component show that the meshing frequency of the reducer is quite different from the natural frequency of the components,and it is difficult to produce resonance,which proves the rationality of the structural design.According to the engineering drawings of the key parts of the reducer,the corresponding processing scheme is put forward,and the prototype of the reducer is completed by selecting suitable processing equipment.According to the application requirements of precision reducer in industrial robots,different types of test platforms are designed and built.Through testing the reducer prototype,the actual performance parameters of transmission efficiency,transmission error,torsional stiffness,backlash and overturning stiffness of the reducer prototype are obtained.The results show that the transmission efficiency of the reducer prototype is higher,transmission error is smaller and backlash is smaller.Compared with CSG-14-50 type harmonic reducer,the torsional stiffness and anti-overturning ability of the prototype reducer are stronger.