Kinematics Research Of The Constant Velocity Of Tripod Sliding Universal Joint

This paper first analyzes the structural types of different constant angular universal joints and compares their respective characteristics. The structural characteristics of the constant velocity of tripod sliding universal joint are also studied in this paper. In order to understand the kinematics of the tripod sliding universal joint, its kinematic equations are established, and then Matlab software is used to solve the obtained models, through which the influence of the joint angle, the rotating radius of the input shaft and the length of the output shaft on its kinematics is measured. At the same time, its many kinematics cures are drawn according to it.The research results show (1) this joint is a quasi-constant-velocity of tripod sliding universal joint; (2) small rotating radius , long output shaft and small joint angle contribute to the improvement of synchronization performance and steady transmission.In the kinematics of twin tripod sliding universal joint, the comparison of the structural characteristics between the original tripod sliding universal joint and the improved one is made .Then degree of freedom of two types of twin tripod universal joints is solved. The kinematics of the improved twin tripod sliding universal joint is studied by theories. In this study, the direction cosine matrices are selected as the major mathematics tools. The equations of the input-intermediate angle relationship, the intermediate-output angle relationship and the input-output angle relationship of the twin tripod sliding universal joints with its output axle fixed with a self-aligning bearing are obtained by precise derivation. The conclusion is obtained that the twin tripod sliding universal joint is a quasi-constant-angular-velocity universal joint.Lastly, by using three-dimensional modeling software Pro/E, the 3d parametric model of twin tripod sliding universal joint is established and then its simulation analysis of kinematics characteristics is performed. Next, each kind of kinematics simulation analysis is performed in the following three groups, that is, the original twin tripod sliding universal joint, the improved one and the pair clearance of the twin tripod sliding universal joint. Furthermore, the comparison of kinematics characteristics is each made in the next two groups: the original twin tripod sliding universal joint and the improved one; the pair clearance of the twin tripod sliding universal joint and the joint with no pair clearance. The author of the present thesis draws the conclusion that the improved output shaft of no pair clearance and tripod will move more steadily. The constant angular velocity characteristic of the twin tripod sliding universal joint is obtained afterwards.Through all the analysis above, a new theoretical method of twin tripod universal joint is found based on the theory of the single tripod universal joint, which can supply both the theorical and practical guide for the research of twin tripod universal joint. Thereby laying the foundation for the further research of the constant angular velocity of twin tripod sliding universal joint.