| The tripod sliding constant velocity universal joint is a new universal joint with high efficiency. It has the advantages of compact structure, simple machining technology, low manufacturing cost, steady transmission, excellent synchronization performance and high transmitting capacity. The thorough analysis and research on the tripod joint will provide a theory guidance for its design and production, which is useful to accelerate the industrialization process thereof.On the basis of structural analysis, the kinematics and dynamics models of the tripod sliding constant velocity universal joint were established by direction cosine matrix tool and coordinate transformation method. MATLAB software was used to solve the obtained models. The research results show (1) this joint is a non-centering and pseudo constant velocity universal joint; (2) the kinematic parameters and forces of each link in the joint vary periodically with the rotation of the input shaft; (3)Small rotating radius , long output shaft and small joint angle contribute to the improvement of synchronization performance and steady transmission; (4)in general, small friction coefficient, input torque, mass and moment of inertia, low angular velocity can cause small forces of the links; (5) small rotating radius and joint angle are helpful to decrease the fluctuation amplitude of the forces.The main geometric parameters of the tripod sliding universal joint used in the x(s)M-1.7L laboratory mixer were determined according to its actual working conditions. Then a virtual prototype of the joint was built based on multi-body dynamics theory and the simulation was conducted with the dynamic analysis software ADAMS. That the simulation result accords with the theoretical result of the joint with no pair clearance implies both the theoretical models and the virtual prototype are correct. And the simulation result of the joint with pair clearance indicates that pair clearance influences the capacity of the tripod joint. Small clearance in the cylindrical pair between the inner ball and tripod bar is benefit to constant transmission. However, the contact and impact of the two links occurs more frequently and intensively with small pair clearance in the tripod joint. This can cause serious oscillation of velocity and acceleration and large impact force. In order to get steady transmission and small energy loss, reasonable pair clearance should be devised in the mechanism.Next, the finite element model of the tripod joint was built and the FEA(Finite Element Analysis) software ANSYS Workbench was used to analyze its dynamic performance and fatigue life as a whole. Modal analysis gave the natural frequency and modal shape of the joint and predicted the vibration response to exciting load. Analysis of harmonic response found out the peak frequency of the joint possible to resonate and the stress and strain under peak frequency. The transient dynamic analysis researched the dynamic stiffness and strength of the joint by investigating the maximum stress and strain when it transmits torque. In the fatigue life analysis, the nominal stress method was applied to predict the fatigue lives of the tripod joint with different connecting shapes and dementions between the tripods and outshaft. The simulating results indicate that the tripod sliding universal joint designed for the x(s)M-1.7L laboratory mixer is feasible and it satisfies the dynamic stiffness and strength requirement. Further, the fatigue life of the tripod joint can be prolonged when the links are made with reasonable shapes and sizes.In short, thorough research of kinematics, dynamics,dynamic performance and fatigue characteristic on the tripod sliding constant velocity universal joint was carried out in the dissertation. Some valuable conclusions were drawn as a result which would provide a better basis for the developing and applying of the new tripod joint.
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