Design And Experimental Research Of Universal Knife Roller For Bionic Intelligent Soil Preparation Machine

Agriculture is the foundation of the national economy and agricultural development has an important position in Chinese economy, but agricultural development must depend on the progress in science and technology. The agricultural machinery is the carrier to realize agricultural science and technology progress in agricultural production, advanced agronomy must be supported by advanced agricultural machinery to play a role of increasing yields and efficiency on large scale, in a high-efficiency and standard way in agricultural production. According to the characteristics and actual situation in the dry farming region of northern China, combined with the subject of Research and Development of The Intelligent and Bionic Operating Machinery which belongs to the major project'Research of multifunctional agricultural equipment and facility'in the eleventh Five-year Plan, based on an analysis of the factures of the existing tillage implements in the country, towards the target of developing a bionic and intelligent soil preparation machine which can realize combined operation, a universal blade rotor has been developed through innovative design, which can complete both rototilling and stubble breaking, and reduces energy consumption and manufacturing costs, improves the operating efficiency and saves operating costs.The motion form and working conditions are analyzed for the universal blade of the bionic and intelligent soil preparation machine; the lowest speed is n≥108r/min and n≥358r/min in the stubble breaking operation. Therefore, we choose the rotating speed between 160r/min and 260r/min in the rototilling experiment of rototilling and between 380r/min and 460r/min in the stubble breaking experiment. Combined with the methods of designing the rotary blade and stubble breaking blade, through an analysis of the structural parameters of the existing rotary blade and stubble breaking blade, choosing the form of blade curve and structural parameters of the blade, nine universal blades with different structural parameters were designed and single rototilling and stubble breaking blade power consumption experiments were conducted in the laboratory, obtaining the optimal combination of structural parameters and major and minor factors which affect power consumption.Using the optimal parameter combination (The bending angle is 67°, The bending radius is 20mm,The angle of slide cutting of the sidelong edge is 12°and the width of single blade is 60 mm.) obtained from the stubble breaking experiment we conducted the optimal design of the universal blade.Taking the operating depth, rotor rotating speed and forward speed the machine and other working parameters as variables, orthogonal polynomial regression analysis was conducted to investigate, the effect of the working parameters on power consumption of single bade .From the experiments we obtained the major and minor factors in the effect of working parameters on power of sigle blade, rotating speed, operating depth and forward speed. The regression equations are established for the relationshio between the single blade power consumption and the rotating speed, operating depth and forward speed in the rototilling and stubble breaking experiments respectively. From the regression equation, it can be known that the quadratic effects exist between the rotating speed of the rotor and forward velocity of the machine in the rototilling experiment, while in the stubble breaking experiment; the quadratic effects exist between the rotating speed and the operating depth. The significant primary interactions exit between the rotaing speed and the operating depth in both of the experiment. According to the requirements of blade arrangement the V arrangement method is established to meet the requirements of the multiple spirals. Universal blades'multiple spiral arrangement is improved by using Delphi language.Universal blades'mounting holes are determined by blade's arrangement.Each hole is arranged by its own spiral, and there is no interference between them. The blade disc of the bionic intelligent soil preparation was designed. According to operation demand, the distance between the disc was determined.The universal rotor shaft with hollow structure was designed sutiable for teo-row soil preparation machine. The strenghth check of the rotor shaft was conducted, and the results showed that it satisfied the strength requirement. In order to test the operational performance of the universal rotor, field tests were conducted, and the results showed that the average broken soil rate is over 85.6% and the stability coefficient of the tilling depth is over 92.51%.In the stubble breaking operation, the average broken stubble cutting rate is above 74.3% and the stability coefficient is above 92.7% in high stubble field and 81.26%and 92.35% in the normal stubble field.The working quality can meet the requirements of follow-up sowing.In sum, the research is beneficial to futher study on the combined rototilling and stubble breaking machine, improving the working efficiency, reducing energy consumption and operating cost of the machine.