Dynamic analysis of working device of excavator based on limit trajectories

SUN Hao-ran1, REN Zhi-gui1,2, WANG Jun-li1,2, LIANG Yang1, WEI Wan-xing1
（1.School of Mechanical Engineering, Shaanxi University of Technology, Hanzhong 723000, China;
2.Shaanxi Key Laboratory of Industrial Automation, Hanzhong 723000, China）

Abstract: Aiming at the study of dynamic characteristics of the working device of hydraulic excavator, a method of force dynamic analysis of the hinge points of the working device was presented. Using the theoretical excavation force model, the theoretical excavation force distribution along the limit excavation trajectories of bucket excavation and bucket bar excavation was calculated. Through the reasonable simplification of the three-dimensional model of the working device, the dynamic simulation model was established. The correctness of the dynamic model was verified by comparing the maximum digging point and its actual coordinate position in the simulation trajectory. The dynamic simulation of two limit excavation trajectories was carried out with the bucket excavation force and the bucket rod excavation force as the load respectively.The results indicate that the hinge point force of the working device changes dynamically with the theoretical excavation force during the excavation process. This study provides a theoretical basis for the study of dynamic characteristics and dynamic stress analysis of hydraulic excavator working device.
Key words: excavator; working device; limit excavation trajectories; dynamic load; dynamic analysis