Study On A New Type Planetary Reducer With Double-Crank And Internal Gear Board

Ring-reducer(single-ring,double-ring,three-ring,four-ring and balance-reducer etc)is a N-type planetary gear transmission device with few teeth number difference. The characteristic of the ring-reducer is that when input shaft revolving,the planetary gear(internal gear)is not making cycloid motion but doing circumference translation under the guiding of a double-crank mechanism which is high speed shaft that have two eccentric bearing locations. The reducer have series characteristics such as simple structure,high driving ratio,small volume,large capacity and high efficiency. But many problems occur when it works under the condition of high speed and heavy loading. These questions including high vibration,great noise and the early-worn of bearing which have been the key technology problems to be sloved.In order to solve the problems of high vibration and great noise coming from ring-reducer under the condition of high speed operation,heavy loading,this dissertation provides a new type planetary reducer with double-crank and internal board based on the analysis of structural feature,transmission principle and problems of current ring-reducer. The new type reducer consists of two stages transmission,one is normal planetary gear transmission and the other is planetary transmission with few teeth number difference. The new type reducer have the characteristics of small volume,high efficiency,large capacity and operation stability. Load transmission system,power flow,transmission efficiency and load capacity are analyzed in the dissertation,and also,gear profiles are modified on the two transmission gear pairs of the reducer. The main contents as follows:â‘ Bring forward a new kind of ring-reducer that is the new type planetary reducer with double-crank and internal board. Design the structure and geometric parameters of the reducer and calculate the gears parameters of two stages. Set up a three-dimension model of the new type reducer and assemble the model under the virtual condition in the software of I-DEAS.â‘¡Separate the various load transfer components that compose of the new type reducer,Analyze the load situation of each part of the reducer though taking every component as isolated part,and obtain the load situation by the basic component of the reducer. Analyze the system characteristic problems such as power flow,force moment,transmission efficiency etc of the new planetary type reducer with double-crank and internal board,Provide the calculation formula of the system characteristics such as transmission ratio,power split flow,transmission efficiency etc. According to the parameters of the prototype designed,calculate that the transmission efficiency of the new reducer can be up to 91.9%.â‘¢Set up the contact FEM of two stages transmission gear pairs of the new type planetary reducer with double-crank and internal board in the software of ABAQUS,calculate the contact stress of the two stages transmission gear pairs of the new type reducer by using finite elements analysis technology and get the Mises stress value and the actual pairs of meshing teeth.â‘£Based on the theory of gear modification research,the two stages transmission gear pairs of the new type planetary reducer with double-crank and internal board is modified on its teeth profiles. The results indicate:the load capacity of transmission gear pairs have enhanced greatly after modification.