Study On Hydraulic Driving System Of Loader

Loaders are widely used in roads,railways,ports,water conservancy,military and other construction projects,is one of the most widely used construction machinery.At present,China's general large-scale loaders generally use hydraulic machinery transmission.There is the efficiency and power between the incompatible transmission characteristics,low-speed high torque efficiency is low.With the continuous improvement of the accuracy of hydraulic components,hydraulic system functions continue to be strong,efficiency and performance of the continuous improvement of the application of hydraulic transmission is also constantly expanding.Previously,such as bulldozers,graders,loaders can only use mechanical or hydraulic mechanical transmission machinery.Now they can also use the hydraulic system as a drive-driven transmission.This can solve the mechanical work in the process of frequent changes in the load caused by a wide range of hydraulic shock,low efficiency,burst and so on.It is of great practical significance to study the advantages of large and medium-sized loader with hydraulic drive-driven transmission system and make full use of the advantages of hydraulic transmission.Based on the analysis of the characteristics of the loader,this paper analyzes the problems of the hydraulic transmission of the loader,and puts forward the scheme and control strategy of the hydraulic drive system.According to the matching principle between engine and hydraulic system,kinetic and kinematic analysis results,hydraulic system pressure setting principle,the diesel engine,hydraulic pump,hydraulic motor and other major components were selected to match.Finally,the model of the hydraulic drive system of the two-stage loader and the hydraulic drive system of the stepless loader are established by using the AMESIM simulation platform.From the start,the response to the step load and the response to the sine wave load in three aspects,the simulation analysis and comparison.It is concluded that the stepless system is superior to the two-step system in terms of the pressure stability of the system and the fuel consumption of the diesel engine.