| Press is a punching machine which arranged the particle or powder materials in a die hole.With the rapid growth of the tablet market demand,tablet machine applied more and more extensive.High efficiency and low cost has become the main development trend of tablet machine product design.Tablet machine feeding mechanism is one of the main components,cam mechanism was currently used mostly,make full use of the characteristics of cam mechanism with fewer components,small volume and high speed starting space stability etc..How to improve the motion performance of the feeding cam mechanism became research focus of the feeding cam mechanism because it achieved reduced vibration,improve the goal of design efficiency and level.Based on this,this paper carried out research in this area.At first,this research design transmission scheme of feeding mechanism of pressing machine,put forward the evaluation method of transmission scheme and determine the specific implementation plan,which uses cam mechanism as tablet machine feeding mechanism scheme according to the function request of feeding mechanism of pressing machine.Secondly,analysis of shortcomings of motion law of cam follower of existing pieces,put forward the motion law general correction method,derived better characteristics five degree polynomial modified expressions and combined motion law,analysis and determine selection range of parameters in the expression and modified scope of application of the motion law,solves the defect of existing motion law existence in increase acceleration at most motion segment.At the same time analyzed the correlation processing method of tracks reservation,in this way improve design flexibility.Thirdly,this research presents the optimization mathematical model of feeding cam mechanism of tablet press space under the goal of minimum size,analysis the method to determine the scope of basic circle radius and eccentricity range in accordance with cam rotary center,deduces the analytical simplified formula for calculating the corresponding boundary values,carry on cam mechanism in the stress analysis,obtained the contact stress,pressure angle and curvature radius formula.Base on this,establish a reasonable and feasible constraint conditions.Reasonable size of cam mechanism is obtained meet the complex constrained conditions,results show that can make the space size decreased 9.4%transmission system.Finally,combined with MATLAB to compile automatic analysis system software of feeding cam mechanism of tablet machine size optimization and motion law correction,achieved the goals of friendly interface,easy to use and improve the efficiency of design,and verify the effectiveness of the program and the reliability for example.At the same time,used SolidWorks and Adams on the tablet machine feeding cam mechanism by the modeling and kinematics simulation and feature extraction simulation of the curve,the results are compared with the theoretical calculation,this paper further verify the correctness of the design method of the cam,and lay the foundation for the subsequent dynamic analysis. |
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