Integrated Desgin And Research Of Backhoe Hydraulic Excavator Working Attachment’s Structure And Performance

Hydraulic excavator is a kind of construction machinery which is very necessarilyand commonly used. It has significant importance in such areas as energy exploition,road construction, national defense construction, irrigation and other earthworkconstruction. With the increasing investment of our country in the infrastructureconstruction, excavator plays a more and more important role in the country’smodernization construction. Therefore, paying attention to its development, acceleratingits innovation and improving its quality are meaningful for our country’s modernizationconstruction.Working attachment is an important part of hydraulic excavator. The quality of theworking attachment greatly affects the performance of the machine. Therefore, strengthanalysis and optimum design for the working attachment will directly affect thesecurity,reliability and the work performance of hydraulic excavator.Since it is not easy to realize the automatic cycle of structure optimization usingfinite element analysis software and the complexity of the hydraulic excavatorperformance optimization, this paper proposes structure and performance integratedoptimization design of backhoe hydraulic excavator working attachment. The maincontents of this paper are listed as follows:①Analyzing and summarizing the structure form and digging characteristics ofthe backhoe hydraulic excavator; then, creating the kinematics model and mechanicalmodel of excavator working device, and solving the coordinates of each hinge point onthe work unit and theoretical digging force through motion analysis; finally, completingthe force analysis of each hinge point which considering the unbalance loading andlateral forces.②Hydraulic excavator working device strength analysis software on the basis ofmechanics of materials utilizing VB is programmed, then the maximum stress of eachsection on the boom and arm is calculated through the software; then comparisonbetween the results of FEA and compiled software is made by case study. Analysing thecomparison of the results, it shows that strength culculated from self-compiled softwareis consistent with that from commercial finite element analysis software.③Having verified the correctness of self-completed software, structural optimization of boom and arm aiming at decreasing the weight of working attachment iscarried out through the method of modern design optimization. The procedure takes thestructural parameter of working device as variable without eliminating the strength ofthe working device in VB compiled software. The results a certain optimizing designcase is contrast to the original parameters. Analysing the comparision of the result,itshows that both the arm and boom are lighter.④Aiming at decreasing the weight of working device and improving the diggingperformance, combining with working device structural optimization software andhydraulic excavator performance optimization software, integrated optimization of theworking device with multi-objective is achieved. And the hydraulic excavator structuraland performance integrated optimizing software utilizing VB is compiled. At last, theresults of optimization will be compared with the original parameters through a casestudy. Comparing the results,the optimized arm and boom are less heavier, in otherwords,the digging performance of the excavator is improved.