Dynamic Study For Working Mechanism Of Crusher With Multi-joint Clearance

The machinery industry is moving into the advanced、precision and sophisticated developmentstage, heavy load, high speed and high-accuracy is becoming the goals of the mechanical productdevelopment. Performance optimization and accuracy of the crusher comes into being.But, pairclearance existence in mechanical systems will cause the contact between the shaft and sleeve, as aresult,severe vibration will be produced. Compared with the non-clearance joint,the velocity,acceleration, joint reaction force, balance torque amplitude can reach several times even ten times incollision which increasing the dynamic stress of the component, causing vibration, noise,accelerating wear and tear, lowering efficiency and precision,causing a great bad impact on themechanical efficiency and lifetime. Therefore, analysis of dynamic characteristics with clearance andflexible members consider is indispensible.firstly,This paper introduces the several research model of pair clearance at home andabroad.And it introduces the development situation of jaw crusher,including its basic structure andmaterial.It introduces the soft body briefly.then useing the solidworks software builds the3D modelof PE-250*400jaw crusher. Virtual prototyping technology and ADAMS software are introducedpreliminarily.Secondly, Importing the3D model into ADAMS software and adding boolean merger，constraints and driving on the crusher to kinematic analysis.Then according to the analysis calculatesbreaking force and speed values which is verified to the real.Next,using the software ADAMS tocreate the crank rocker mechanism of crusher.According to the equivalent spring damper model andthe theory of “separation-contact” pairs model to establish the clearance contact model and thefriction model to describe the motion pair clearance characteristics, and confirm the parameters ofthe equivalent spring damper model. And introducing the detailed steps of establishing the clearancecontact model and friction model for the eccentric shaft (crank) and the movable jaw (link), themovable jaw (link) and the bracket(rocker), the bracket(rocker) and the frame. Finally adding loads,constraints and drive to the virtual prototype model for dynamic simulation.One focus of this study is to find the specifc changes and rules by comparing dynamic characteristics of crack and rocker mechanism with gapless and three clearance,different clearanceradius,different crank angle speed and different number of clearance.And seek to find the bestclearance fit. The second research focus is that it makes an emphasis on the analysis of dynamiccharacteristics of mechanism with clearance in considering the flexible component factorscomparing with the rigid component simulation. The results show that,the flexible constructionmember can cushion the effect of collision, making the mechanism is very close to the ideal state.Analysis of dynamic characteristics with clearance and flexible members provides a theoretical basisfor Optimizing the design and manufacture of jaw crusher and improving its prolong life.