| Loader is an machinery widely used in roads,railways,ports,docks,coal,mining,water conservancy,national defense and urban construction.The steering system is one of the most important system in wheel loader,it determines driving security,the work efficiency,fuel consumption and the labor intensity of driver.How to design wheel loader's steering characteristics,make loaders have good performance and higher operating efficiency,has always been an important issue.to the production enterprises and research institutions.Steering Mechanism is an important and indispensable part of Wheel loader,It?s design quality not only affect the traction loader,mobility and steering stability,but also related the safe operation of loader directly.so that Loader steering mechanism of the design requires a high degree of attention.Wheel loader steering Mechanism can be divided into tilt steering wheel,articulated steering and skid-steering,etc.Articulated loader frame is divided into two parts: front frame and rear frame.By the pin connection,the frame maintain or change the relative angle by the cylinder.Articulated steering Do not need articulated steering trapezoid,.the Meeting point of front and rear axle In the horizontal plane,so it is more simply.MATLAB is a powerful calculation software Launched by the Mathworks Inc.Optimization Toolbox of MATLAB function library provide users with a variety of optimization problems for a complete solution,Covering linear programming,quadratic programming,nonlinear programming,square problems,nonlinear equations,multi-objective decision-making,the biggest problem with the smallest,as well as issues such as semi-infinite optimization problem.Optimization design is a modern design method according to the optimizing principle and method,and synthesizes the factors of various fields,by man-machine cooperate or"explore automatically",what carried on was designed semi-automatically or automatically on the computer,in order to elected the best kind of design method under the existing engineering condition,it is an effective means to solve the complicated design principle is designing the most; its means is an electronic computer and calculation program; the design method is to adapt and optimize the mathematics method the mast.Articulated steering mechanism is a double thrust agencies,the mission of cylinder?s stroke and arm is difference,This phenomenon resulted in hydraulic oil for non-constant flow,and therefore caused pressure pulsation in the system.Shift caused by the process of vibration,shock.At the same time brought the loss of energy.Therefore,should the fuel tank as much as possible about the trip turned bad,the smallest margin of arm of force.If you want to make the course of the stroke of the cylinder and the arm of cylinder minimum,The overall objective of the function by the composition of two sub-objective function,taken to be divided into n equal angle method,compute the mission of cylinder?s stroke and arm at each position,use the summation as the objective function.The mathematical model based on choice of optimization of the MATLAB Optimization Toolbox function fmincon,in accordance with the format requested by the objective function,nonlinear constraints of the M documents,Hinge point of the original points as the initial optimization,to be design variables,objective function to optimize the results before and after,at the same time,using MATLAB's plot function curves drawn both before and after optimization From the drawn curve and optimize the contrast can be seen before and after the numerical optimization have achieved noticeable progress.Using MATLAB optimization toolbox,select the appropriate optimization method to optimize the design variables.Optimize the results obtained,we can improve the design of the old products.Loader hydraulic steering system is currently a wide variety of systems,technical level,different structural principle,the application of different occasions and different tonnage,a different operating system environment can take different configurations,since the type of hydraulic steering system of many how to select a suitable hydraulic steering system is a major selection problem.At present,the main use of wheel loaders hydraulic boosting steering system, constant flow hydraulic steering system,load sensing and flow amplifier system,and export to Europe to adapt to the needs of the emergency steering system design,also known as the second steering system.Hydraulic system?s temperature on the heat balance of the entire hydraulic system is very important impact to work,if the hydraulic oil temperature is too high,hydraulic oil will soon lead to deterioration of the hydraulic pumps,hydraulic cylinders,steering gear,control valves,high pressure hose and other components will cause a very bad impact.Research and analysis for the different types of steering system pressure loss and its impact on the thermal equilibrium temperature,in the ZL50F loader configuration,respectively,different types of hydraulic steering systems,and test the pressure loss and thermal balance.Loader Hydraulic steering system combines design experience,summed up the following loader hydraulic steering system of application experience.(1) hydraulic boosting steering system and constant flow hydraulic steering system?s flow pressure loss is large,high-temperature thermal equilibrium,as far as possible not to choose.(2) 1.5 tons,3 tons,such as the use of small tonnage loader load-sensing hydraulic steering system,work,hydraulic steering system can share a quantitative pump,with a priority towards the realization of the priority valve so that the full application of engine power.(3) 4 tons,5 tons loaders used load-sensing hydraulic steering system,with two pumps combined quantitative system of work flow to meet demand,reduce system cost,reduce power loss.(4) Flow amplifier system should be used at 6 ton and more than 6 tons Loaders.
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