Development And Research On Wheel Track Adjustable Steering System Of High Clearance Self-propelled Sprayer

Development of high-clearance self-propelled sprayer applicable for China is an effective method for solving the difficulty of chemical application in high-stalk crop. Development of steering system is a one of the basic and important content for the development of whole self-propelled sprayer. And the performance of self-propelled sprayer is directly affected by the performance of steering system. At the same time, the efficiency and adaptability of self-propelled sprayer can be improved obviously by steering system with the function of wheel track adjustment. So it’s also useful to optimize steering system for improving the reliability and shortening design period of the whole sprayer. The paper developed a wheel track adjustable steering system matched with high-clearance self-propelled sprayer, and plenty of research work was carried out. The main research work and conclusions are as follows:Firstly, a kind of wheel track adjustable steering mechanism was designed based on the independently requirement of steering and wheel track adjustment at the same time. The performance of steering system was studied making use of the classic steering theory. At the same time, the static structural analysis was achieved with the key part of steering mechanism based on ANSYS software. The parameters of front steering pole were confirmed according to comparing of the analysis results under different size, different thickness, different wheel track and different load. By the way, the effect of weight and accelerative force to the static structural intensity of steering pole were carried out.Secondly, the size and structure of steering pole were confirmed based on the results of its static structural analysis. At the same time, in order to eliminate the lateral slip of steering wheel and decrease the steering radius effectively, the fixed position of steering cylinders were optimized based on the ADAMS software. It shows that the intensity of steering pole is enough during steering with maximal load. It also shows that the difference of steering angle between calculating result and measuring result decreases obviously. So the reliability and performance of steering system were improved observably through optimizing.Thirdly, hydrostatic steering system was developed and integrated based on the choosing and calculating of all its components. And the maximal steering resistance moment and maximal steering pressure with full load and empty load were calculated according to the range of angle between steering cylinder and steering pole. Meanwhile, the minimum steering radius before and after optimization were calculated respectively.Lastly, the main performance of steering system was studied through experiments and compared with calculated results. Firstly, the maximal steering pressure under dry weight and loaded weight was measured through experiment. It shows that the research results achieved through calculating and experiments are almost the same. Then, the minimum steering radius was measured through designed test before and after optimization of fixed position of steering cylinder. The minimum steering radius decreased nearly18%before and after optimizing. Moreover, the minimum radius measured by experiment is larger than calculating result because the tow-in of steering wheel and total deformation of steering pole were ignored during calculating.In a word, a kind of wheel track adjustable steering system was developed including design, static structural analysis and optimizing of steering mechanism, designing and integrating of steering hydraulic system. And the main performance and reliability of the steering system were achieved through experiment and research. By the way, the paper also points out the content which was needed to be studied further.