Dynamic Simulation Of Working Equipment Of Large Mining Face Shovel Hydraulic Excavator

Mining large face shovel hydraulic excavator is widely used in large water conservancy projects and open-pit mines.Due to its strong material carrying capacity,it has achieved high work efficiency and economic benefits.Generally,the working objects of mining face shovel hydraulic excavator are the mine and rock after blasting.During the operation,the load changes complexly,which has a great impact on the working equipment and the hydraulic system.As the working equipment is the direct execution mechanism of the excavation action,the dynamic characteristics of the working equipment will directly affect the performance of the whole machine.Therefore,in this paper,the common digging and loading device which is widely used in the international mainstream mining large face shovel hydraulic excavator is taken as the research object.And its dynamic characteristics are studied based on the virtual prototype technology.The main research contents of this paper are as follows:Firstly,the mathematical model of the common digging and loading device is established by using the matrix vector method,and the position coordinates of each hinge point at any time are obtained.The mathematical formulas between the swing angle of the boom,the swing angle of the stick and the swing angle of the bucket and the working length of the hydraulic cylinder are deduced,and the correctness of the mathematical model of the working equipment is preliminarily proved by the kinematic simulation with MATLAB.The virtual prototype model of face shovel hydraulic excavator is established by using Pro/E and ADAMS,and the envelope diagram is drawn.The results show that the error between the working size parameters and the sample value is small,which proves the correctness of the virtual prototype model.Secondly,the formulas of stick cylinder theoretical tool force and bucket cylinder theoretical tool force on a face shovel excavator is established by using the torque balance method.By adding a spring with larger stiffness at the cutting edge of the bucket,the distribution of theoretical tool force of the stick hydraulic cylinder in different positions is measured.After properly simplifying the working equipment,the dynamic model is established based on virtual work principle and D’Alembert principle,and the driving force formulas of three groups of hydraulic cylinders are obtained.The dynamic simulation is carried out for the horizontal pushing condition,and the load characteristics of the hinge joint of the working equipment in the excavation process are studied.Finally,the AMESim-ADAMS co-simulation model is established to analyze the dynamic characteristics of the working equipment in the single action process of the boom hydraulic cylinder or the stick hydraulic cylinder under no-load.By adding the digging resistance model,a complete digging cycle of the face shovel excavator is simulated,and the dynamic characteristics of the hydraulic system of the working equipment in the compound digging process are studied.It provides a reference for the design of hydraulic system of working equipment of large face shovel hydraulic excavator.