| In the RV reducer of robot,the most important influence on the motion accuracy is the cycloidal pin-wheel planetary transmission,the processing quality and profile accuracy of the cycloidal gear are the key factors affecting the transmission performance of the RV cycloidal pinwheel.The poor meshing contact characteristic caused by the machining error is the main reason for the low precision of the cycloidal pin motion.The shape of the cycloidal gear is complex and difficult to manufacture,so it’s machining accuracy is very hard to guarantee.As the traditional machining adjustment process is cumbersome and can only be qualitative but not quantitative,the correction efficiency is very low to go against the stability of the processing accuracy of the cycloidal tooth profile.Therefore,by studying the processing principle of the cycloidal gear and processing method of the measurement data,a digital feedback modified method of cycloidal gear tooth surface processing has been proposed based on the measurement data of tooth profile with the domestic gear measurement center in this paper.The main research contents are as follows:1.The principles of the RV reducer cycloidal pinwheel planetary transmission and the processing of cycloidal gear tooth surface have been lucubrated.The transmission ratio between the arm and the cycloidal wheel has been deduced.The complex motion relationship between the grinding wheel and the cycloidal gear has been clarified.The mathematical models of cycloidal gear generating grinding and forming grinding have been established.The mathematical formulas of the theoretical tooth surface and normal vector of cycloidal gear with the grinding parameters of machine tool as variables have been deduced.According to the mathematic model and movement relationship,the digital processing method of the theoretical design tooth surface of cycloidal gear has been put forward,which provides the necessary theoretical basis for the processing and precise detection of cycloidal gear.2.Based on the actual tooth surface data of cycloidal gear measured by gear measuring center,the fitting method of discrete measuring points has been studied,and the equation of the actual processing tooth surface of cycloidal gear has been obtained.By studying the optimum matching method between the theoretical design of cycloidal gear and the actual tooth surface,the calculation model of tooth surface error has beenestablished,and the mapping relationship between the grinding parameters of cycloidal gear machine tool and the processing error of tooth surface has been deduced.The processing error of cycloidal gear has been solved by Newton-Lafferson iteration algorithm.3.Based on the tooth profile measurement data of the domestic gear measuring center,a digital feedback correction method for the tooth surface error of cycloidal gear has been proposed.In this paper,the principle and method of feedback correction of cycloidal gear profile error has been deeply studied,while the model of the digital feedback modified method of tooth surface error has been established.The law of the influence of grinding parameters on tooth surface error has been clarified,and the strategy of feedback modification has been planned.The modification of grinding parameters of machine tool has been obtained by using optimization iteration algorithm.4.The software for correcting the machining error of RV reducer cycloidal gear has been developed,which can digitize the theoretical tooth surface of cycloidal gear,reconstruct and match the actual tooth surface,calculate the tooth surface error and digitize the feedback modification.The experiments show that the digital feedback modified method proposed in this paper can effectively reduce the machining error of cycloidal gear.After the second grinding,the tooth surface error of cycloidal gear has been greatly reduced,which proves that the method can improve the machining accuracy and efficiency to a certain extent. |
PDF Full Text Request