| The thesis feeding mechanism of Heidelberg high-speed printing mechanism is a typical“disc cam mechanism with floating pushrod”.?n this thesis,the coupler-rocker allowable pressure angle condition is introduced into the existing mechanism performance evaluation system,and the class-? mechanism synthesis problem of three evolution mechanisms is studied again.The dimension synthesis theory of disc cam mechanism with the floating positive-radius roller/flat pushrod is based on the principle of velocity diagram.The new concepts of"instantaneous nested interval of three force intersection”,"instantaneous nested interval of cam-roller contact point”,"instantaneous region set/boundary"satisfying?1?[?1]??2?[?2]condition are put forward,the regularity conclusion of instantaneous solution region/boundary under two kinds of transmission performance conditions is analyzed and summarized,and then the"wholeregion set/boundary"is discussed and the analytical expression is given.Finally,the solution method of the most compact mechanism solution is proposed,the class-? dimension synthesis of disc cam mechanism with the floating positive-radius roller pushrod.is solved satisfactorily.The problem of motion fidelity should be considered in the dimension synthesis ofdisc cam mechanism with floating flat pushrod.Based on the discrete boundary and the right hand rule,a new method of checking the motion fidelity is presented.By analyzing the characteristics of the solution region of the cam axis,the solution method of the most compact mechanism is given.The class-? dimension synthesis ofdisc cam mechanism with floatingflat pushrod is solved satisfactorily.Taking disc cam mechanism with the floating negative-radius roller pushrod as the research object,five constraint conditions and checking methods of the mechanism are put forward.By constructing the coordinate system O-r0Ru0,the dimension domain?(r0,R,u0)and"discrete-grid"method,the solution domain and boundary line satisfying single constraint conditions are obtained,and then the boundary/solution domain under merge constraint is obtained by solving the intersection of these solution domains.The existence of dimensional solution space?all and the characteristics of spatial surface(?)?all are revealed by MATLAB.Finally,the solution method of the most compact mechanism solution is proposed,The class-? dimension synthesis of disc cam mechanism with floating negative-radius rollerpushrod is solved satisfactorily.Finally,this thesis had completed the development of visualization software for class-? dimension synthesis of various mechanisms onthe Visual Basic 2019.Through the research on the three evolution mechanisms and their comparison,the necessity of introducing new mechanism performance index was verification,and the internal relationship between the new and old allowable pressure angle condition solution domain was revealed,which had great significance for the theoretical development and practical application of dimension synthesis of cam-linkage combination mechanism. |
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