Optimization Of A Combined Machine For Subsoiling And Land Preparation

Conservation tillage is the future direction of modern agricultural technology. Subsoiling technology is an important part of the conservation tillage technology. Subsoiling can break the hard plow sole of the soil, and build deficiency-and-excess soil structure. Besides, it is an important technology to increase production. Recently agricultural machinery field is lacking in combined operation machines, so the paper designed a new type of combined machine whose aim is subsoiling and land preparation. The vibrating deep pine machine with stubble breaking disc and suppress broken soil roller combine together.The performance and reliability of the new machine can be improved by means of finite element analysis and structure optimization. The performance of key part is also studied and a parametric system for subsoiler is designed whose aim is to quicken the design of disc coulters.Specific contents and conclusions are as follows:(1) According to requirements analysis and by comparing several programs, the complete application and parts programs of the combined machine for subsoiling and land preparation are fixed. Inter-row deep loosening is the type of the combined machine. stubble cutting mechanism, deep loosening mechanism and preparation mechanism are combined together.The stubble cutting mechanism uses passive big ripple disc coulter which is equipped with a spring pressurization. The arrangement form of the subsoiler is single row and vibration technology is to achieve drag reduction. Preparation mechanism adopts a tooth roller type oblique type roller.(2) By designing the test bench that can adjust the sweep angle and tilt angle of disc coulter precisely, this research did four factors and three levels orthogonal tests by using the factors of the type, velocity, sweep angle and tilt angle of disc coulter and the evaluation indices of cutting rate and traction resistance and determined the key components which is using big ripple disc coulter with the velocity of 5Km/h, sweep angle of 5°and tilt angle of 2°.(3) On the basis of mechanical design, using Pro / E software to make three-dimensional modeling of components of combined machine, and three-dimensional virtual model assembly, assemblability of the product has been tested.(4) Based on the theoretical stress analysis, the paper uses ANSYS software to handle and the shovel tip static analysis. It worked out that the maximal displacement of share handle is 4.8×10-2mm and of share tip is 4.75×10-4. And their maximal Von Mises stress are 274 MPa, 349 MPa. According to the results of the finite element analysis, the deep loosening shovel is optimized. After the optimization of deep loosening shovel, the performance has improved significantly.(5) According spraying machine design drawings completed combined machine for subsoiling and land preparation generation prototype production, conducted a field performance test. The results show that the prototype of the stability of the tillage depth, soil breaking rate, surface roughness, soil after tillage disturbance factor, power consumption, slip rate and congestion and other performance indicators are in line with national standards.(6)Using the C + + language to do secondary development for three-dimensional CAD software and Pro / E, completed the design parameters of big ripple disc coulter, which can automatically generate 3D graphics and generate two-dimensional engineering drawings and other functions.