Dynamics Simulation And Finite Element Anslysis Of The Loader Working Device

The loader working device's intensity and stiffness properties directly affect the use reliability and life of the whole products, so the structure design will become the important content of loader integral design. The loader working device is taken as the research object in the thesis to study its kinematic and dynamic simulation and finite element stress analysis, to identify the distribution area of dangerous stress, namely the eccentric loading and ground condition shovel position. Taking it as a theoretical basis to make the structural design of working device in order to get a more reliable and comprehensive program of structural improvements.(1)Model and assemble the loader working device by using three-dimensional modeling software Pro/E, and then got and exported assembly animation.(2)Analysis the loader working condition and the loading manners of external load, and the result is: The insert resistance 245391.81N and shovel dug resistance 361464.88N when symmetric loading; The insert resistance 101039.57N and shovel dug resistance 148838.48N when eccentric loading. After establishing loader working device virtual prototyping model by ADAMS simulation software, did the dynamic simulation and analysis of each operating movement of the device, and then exported the dynamic simulation animation. The results showed: After the work of taking back the bucket, the rise force of turn fights oil cylinder was always more than arm oil cylinder's, which showed it won't happen poured over; In the eccentric loading method, the force of the device system was bigger; Every hinge point borne the maximum force value at the ground shovel dug conditions; so the thesis chosen the eccentric loading method ground and shovel dug conditions as research object in finite element analysis drafts. In the simulation results data, the maximum stress of below arm hinge point approximates 1500kN.(3)Established a simple dynamics structural model. Through the calculation method of the mechanics of materials, every component of device was calculated so as to get load numerical of the maximum stress condition. From the results: the maximum stress value of below hinge point arm is 1510.3kN, which was close to the simulation calculation 1500 kN. Using the finite element resolution software, we analysed the arm framework with finite element method, and found the dangerous stress concentrated in upper and lower parts of arm board which was slanting load and the inside surface of reaming joint, stress range between 948.37 MPa and 632.32 MPa. The stress of welding parts between beam and arm board had exceeded yield limits(345MPa), this position easily happens fracture. The maximal deformation was lower hinge point whose eccentric loading force was larger ,and the maximum deformation was 17.531 mm.(4)According to the results of finite element analysis, the thesis put forward improved modification scheme of arm framework structure and did the finite element analysis on the improved structure. The results showed: In the improved structure, the maximal deformation of the below arm board hinge point shrunked to 11.9 mm; The dangerous stress concentration areas of the upper and lower parts of arm board decreased obviously, and stress range drop to 316.3 MPa - 623MPa;The stress of welding parts between beam and arm board completely disappeared.