Researchtransmission Characteristics Of Heavy-load Conveyer And Analysis Of Key Structure Strength

Chain drive is one important way to pass the motion in mechanical transmission,and widely used in a variety of mechanical transmission systems such as transportation,mining,metallurgy,agriculture and military affairs,because of its reliable economic and performance.But when it used in conveyor mechanism,because its low-speed and heavy-loading,traditional chain drive with loose-side cannot meet with actual requirements of engineering practice.Using slide constrained chain can maximize the capacity of load carrying in a given area,and significantly improved the reliability of conveyor movement;it can enhance the carrying capacity of the transport mechanism effectively.In this paper,a kind of slide constrained chain is developed,and used to convey heavy load which ordinary chain drive cannot achieved.The main research contents as follows:(1)Analyzed the motion characteristics of the traditional conveyor with long chain pitch without slide constraints.The velocity fluctuation is evident,the stability is worse,and the tight side of chain cannot keep tension always.Through applying the slide constraint to the traditional conveyor can greatly improving the motion characteristics of the conveyor.(2)In order to use the space effectively,designing of U-type slide constraint conveyor.Described the trajectory of the pin in a period time,and realized its continuous movement.Then deduced the trajectory of chain center,and got the internal and external constraints slide chain finally.Designing and building the 3D parametrical model of the U-type slide and other components,then the processing the assembly and the kinematics are simulated based the UG software.(3)Simplified the model of the U type slide constraint conveyor,fixed dive wheel and driven wheel with the chain which mesh with them,and the other chains rotate around the corresponding slide center.The chain is simplified into the concentrated mass,and the adjacent chains connected by springs and dampers.Based on the simplified model,dynamic model is established based on Lagrange Equation,then deducing the differential equation of the dynamic.Getting the vibration of the driven wheel and the chain units,this calculated with the Ode45 function in MATLAB software.(4)Import the assembly model into the RecurDyn software,and based on relative coordinate modeling and recursive solution the problem in the mechanism of contact collision is solved.In this model,Simulated and analyzed the velocity and acceleration of the driven wheel,and the meshing impact of chain and sprocket,the impact load of chain motion in the slide with the conditions of the chain carries all load and ultimate load.(5)Analyzed the U-type slide through the finite element method,analyzed the stress and strain of the U-type slide under the maximum stress.The U-type slide frame is analyzed by the finite element modal analysis,and obtained the natural frequencies and the mode shapes.