Research And Design Of Multi-curved Section Globoidal Cam Mechanism

Globoidal cam indexing device is the key component for carring out high speed and high accuracy indexing motion,it is widely used in intermissive displacement of automatic machine,but it is difficult to design and manufacture,meanwhile,the limited load capacity occurred.Multi-curved section globoidal cam can be used to improve mechanism load capacity in terms of increasing the degree of roller and cam coincidence.This paper propose offset and redundancy curved surface to solve the two major problems that exist in the design and application of the cam.Using the new method can also improve the accuracy of construction and reduce processing difficulty.Based on the theory and technology of traditional globoidal cam mechanism,a new method is proposed with the help of moden mathematic to construct precise mathematic modeling of multi-curved section globoidal cam.The new design method can extend load capacity of the globoidal cam mechanism efficiently,while lessen the difficulty of processing.Through the CAD/CAE digital technology to design and analyze the structure of globoidal cam by using the new method.Several solid examples were conducted to verify that the benefits of multi-curved section globoidal cam mechanism in terms of loading capacity and processing complexity.This paper adopt computer simulation and geometry 3D modeling softwares(eg.kinematic,dynamic analysis,etc.)to verify and optimize the design.Based on the simulation experiments,the mandrel force and elastic deformation are calibrated to the pin roll,the minimum size of the pin roll is discussed by applying different moments to the driven turntable.The contents of the study are as follows:(1)Based on the transformation tensor and differential geometry theory,introduce the contour surface functions and the motion law of multi-curved section globoidal cam mechanism.Visualize the 3D model of proposed cam structure instance,verify the simulation and analysis of models.(2)Different multi-curved section globoidal cam mechanism were designed,verify these designs by kinematic and dynamic simulation and analysis.Elasticity analysis of the pin roll is carried out.The conclusion that the selection criteria of the shaft roller size are obtained,the theoretical basis and the research method are provided for the design and parameter selection of the curved surface cam mechanism.(3)According to the analysis of different type cam camshafts,the bearing capacity of the offset type redundant globoidal cam mechanism is improved effectively.The kinematic and dynamic performances of the offset type globoidal redundant cam mechanism are demonstrated by simulation results.(4)Proposed the offset type redundant globoidal cam mechanism.After invoking the kinematic and dynamic performance,applied offset type redundant globoidal cam mechanism to the design of the cam splitter.According to the mechanical parts manual,the parts and the structure of cam divider are designed while the virtual prototype is established for verify the rationality of the design.Then draw 2D drawings for the parts to prepare manufacturing in the next step.