| Since the 21 st century,the demand for computers,household appliances and automobiles in the domestic market has increased,which makes the development of semiconductors and electronic components in China further.In China,higher requirements are put forward for the manufacturing accuracy of parts,and the demand for fine blanking parts is also growing.The fine blanking parts are developing towards the direction of high quality and efficiency.Therefore,the research on precision presses is particularly important.In this paper,the precision press is taken as the research object,and the main motion mechanism scheme design,the scale optimization design of the linkage mechanism,the design of the main motion mechanism components,the error analysis of the linkage mechanism and the accuracy design of the linkage mechanism are carried out.The specific contents are as follows:First of all,based on the main motion mechanism of general crank slider mechanical press and screw press,by adding the bar group,the six bar mechanism plan and the mechanism plan of hybrid press are put forward.The main motion plan of the press is selected by are analyzing and comparing advantages and disadvantages of each plan.According to the design requirements of the press,the size of the plan is preliminarily designed and the motion of the components are divided.This paper analyzes the influencing factors of the slider motion parameters,considers the velocity and acceleration of the slider comprehensively,and optimizes the scale of the mechanism by the parametric design and optimization module of Adams.Secondly,based on the above design,the dynamic static analysis of the press is carried out to obtain the stress conditions of each component.According to the empirical formula and the actual requirements of the press,the crankshaft,slider and box are designed.Then,the finite element theory is used,and the finite element analysis software ANSYS Workbench is used checks the strength of the existing design.According to the actual working condition of the press,the guide rail of the press is designed and selected;according to the theory of maximum profit and loss work,the flywheel of the press is designed,and the actual moving speed of the system is solved through numerical analysis by the numerical simulation software MATLAB is used to solve the problem,so as to analyze the regulating effect of the flywheel on the speed fluctuation and determine that the flywheel design meets the requirements.After that,it studies the causes of the errors of the press mechanism,summarizes the methods of the kinematic accuracy analysis,the theory of the loop increment method was studied.Considers the error of the length of the mechanism rod and the accuracy of the installation and positioning,the error transmission model of the mechanism was established to solve the kinematic accuracy of the slider.By the significance degree to express the influence degree of each factor on the kinematic error of the slider,and the main influencing factors of the kinematic error of the slider was get.Finally,based on the workpiece processing cost and the sensitivity of various factors,the adjustment sequence of component tolerance is determined.The initial tolerance design scheme is adjusted by synthesizing the accuracy of the mechanism,so as to improve the probability that the slider motion output falls within the allowable error range.So that the mechanism tolerance design scheme can meet the requirements of position reliability and angle reliability.Through Monte Carlo simulation,it is verified that the scheme meets the accuracy requirements after accuracy synthesis. |
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