Under The Condition Of Change The Ratio Of Normal And Tangential Digging Resistance On Digging Performance And Strength Analysis Of Backhoe Hydraulic Excavator

Hydraulic excavator is mainly machinery in the field of engineering machinerybased construction, it has very important position in the earthwork construction such asindustrial construction, road construction, water conservancy and mining engineering.Hydraulic excavator completes digging operations by work device. Working deviceperformance is an important symbol of the whole machine design level. Many studieshave shown that hydraulic excavator digging adhesive soil like clay, the normalresistance in the whole process of digging is disordered, irregular and there is noobvious relationship between tangential resistance. Therefore, the traditional hydraulicexcavator digging performance analysis need to change. Changing the ratio of normaland tangential digging resistance(λ) to variable and selecting the most appropriateresults from a series of results can make the hydraulic excavator digging performanceanalysis and strength analysis more reasonable and reliable.This paper will select a21t backhoe hydraulic excavator as the research objectand choose specific digging conditions, using the modern design method, taking use ofVB, ANSA and ANSYS software, considering the influence ofλ,then analyze backhoehydraulic excavator digging performance and strength of working device and comparewith the results of traditional method. In this paper, specific research contents asfollows：①Analyzes and summarizes structure form and digging characteristics of thebackhoe hydraulic excavator; creates the kinematics model of excavator workingdevice, solves the coordinates of each hinge point on the work unit, center of gravityand the position of the bucket tip through motion analysis②Calculates the each moment of oil cylinder of backhoe hydraulic excavatorworking device by using mathematical methods; creates the mechanical model of thetheoretical digging force of whole machine by considering excavator oil cylindermovement situation in practical work (active or passive); based on consideringinfluence ofλ, puts forward a new calculation method of the theoretical digging forceof whole machine which provides the basis for the next step of digging performanceanalysis.③By using the self-developed software to draw digging map include thetraditional method and considering influence ofλ,then compare two different results； analyzes digging performance of backhoe hydraulic excavator by using the method ofdigging map overlay analysis.④Considering the influence of λ,the intensity of the main structure of the workdevice was analyzed when the backhoe hydraulic work under extreme conditions byusing FEM software ANSYS; then compared with the analysis results of traditionalanalysis methods.