Lightweight Optimization Design Of RV Reducer

Since entering the 21 st century,intelligent manufacturing with industrial robots as the carrier is occupying the mainstream.Among them,the RV reducer is an important component of the industrial robot arm.The size of its mass will affect the service life of the robot arm and the working accuracy of the robot arm.Therefore,reducing the weight of the RV reducer is the only way.However,high-performance RV reducer is still mainly imported in my country,and the RV reducer has a complex structure and consists of many parts.Therefore,taking the RV reducer as an example,the lightweight optimization design and verification are carried out.First,by studying the components and transmission principle of the RV reducer,the speed,transmission ratio and operating frequency of the system are deduced and calculated.Starting from the forming principle of the cycloidal gear tooth profile,the curve is drawn in Matlab,so as to select the cycloidal gear tooth profile modification method,which provides parametric support for the subsequent cycloidal gear modeling.Through the analysis and calculation of the overall force of the angular contact ball bearing,tapered roller bearing,crankshaft and planetary gear of the RV reducer,the bearing force on the planet carrier and the pin gear housing is obtained.Based on the solid modeling of the RV reducer,the kinematics simulation of Adams was carried out to obtain the rotational speed and transmission ratio of the system at all levels,and the simulation results of the system were compared with the theoretical values to verify the accuracy of the model.Secondly,by comparing the finite element modal simulation of the RV reducer with the working frequency,it is found that the frequency of the reducer is not near the working frequency,so there will be no resonance,but there is a resonance problem between the parts.Based on the calculated bearing force,the static analysis of the reducer is carried out to check the stress of the reducer under the extreme working conditions,and the results are all within the material strength range.On this premise,the lightweight topology optimization of the pin-tooth housing and the planet carrier is carried out,and the optimized parts are designed and modeled with reasonable material removal.The static analysis is carried out again to obtain that the stress is almost unchanged from the stress before optimization,and the modeling is carried out.The frequency of the optimized parts is not similar to the original planetary gear frequency,but will be similar to the original planetary gear frequency.Therefore,the topology optimization of the planetary gear is carried out with the natural frequency of the constrained state as the optimization goal.Modal analysis was carried out on the re-modeling design of the optimized model.The frequency of the state analysis is not near the frequency of the planet carrier and the pin-tooth shell.For the calculation of the bending strength of the tooth root of the planetary gear,through the dynamic analysis of the optimized planetary gear and the comparison of the bending strength,the rationality of the lightweight optimization design of the planetary gear,pin housing and planet carrier is verified.Finally,machining and assembling of parts optimized for RV reducer.The transfer capability test of the RV reducer is facilities on the built test bench.The measured transfer ratio of the reducer is 121 and the calculated value is consistent,and the transfer efficiency of the RV reducer is 82.2%.When the torque is small,the increase of the transmission efficiency is obvious.When the torque is large,the increase of the transmission efficiency is not obvious.The efficiency curve is consistent with the standard curve.The transmission error experimental analysis is carried out and it is concluded that the transmission error of the optimized reducer is less than 4′ to 5′.In line with the design standards of the reducer,the quality of the main components of the RV reducer has been reduced on the basis of ensuring the performance of the RV reducer.The topology optimization method provides a new research direction for ensuring the accuracy of the reducer and prolonging the service life.