Dynamic Analysis Of Cutting Unit Of Electric Shearer Under Typical Working Condition

Coal resources play a leading role in the energy structure of our country,and provide enough impetus for the development of our economy.The drum type electric traction shearer is the main coal production equipment in the fully mechanized coal mining face.The cutting part is the main working mechanism of shearer.Coal shearers have more types of working conditions for cutting coal.Under different working conditions,the cutting force of shearers is different,and the forms of failure and damage are different.It is important to study the dynamic response of shearers under different conditions to improve the reliability,service life and productivity of the fully mechanized coal mining face.In this paper,the cutting part of drum type electric traction shearer is taken as the research object.Based on multibody dynamics theory and rigid flexible coupling theory,with finite element analysis and virtual prototyping technology,we analyze the dynamic response of cutting unit of shearer under typical working conditions.First,using LS-DYNA to do coal cutting simulation,we got the operating load of roller under different working conditions.Under oblique cutting condition,the number of bending segments in the pin row is 13.Then,based on the theory of rigid body dynamics and the rigid flexible coupling theory,we established the rigid flexible coupling model under Linear cutting condition,oblique cutting condition and dip angle condition,and have analyzed the dynamic response of rocker housing and lifting bracket under different working conditions.The analysis shows that the larger stress area of the front and back rocker housing is concentrated in the intersection area between the planet head and the fixed axis transmission gearbox.The larger stress area of the front and back lifting bracket is concentrated in the bending section of the lower end of the joint of the oil cylinder.After the dynamic simulation of cutting part transmission system under constant load,impact load and random load.We analysis variation of the meshing force and the gear shaft force.The result shows that there is a 90 degree phase difference between X direction meshing force and Y direction meshing force of planet gears.The peak value of meshing force will be more fluctuant in the case of random load.At the start stage,the gear shafts will be subjected to large impact loads.Based on the combined simulation technology of ADAMS and ANSYS,the transient dynamics analysis of transmission system of first stage and second stage planetary frame shows that the larger stress area is concentrated on the area of protruding shaft.Using ANSYS-nCode,with load of transient analysis of rocker and strength analysis results,we predict the fatigue life of the rocker.The results show that the intersecting between the head of the planet and the gear box of a fixed axis gearis is a short area of life.