关键词: 圆捆机, 卷捆机构, 逆向工程, 反求设计, 结构参数, 卷捆试验

Abstract: Steel roll round baler is one of the key technical equipment for straw harvesting in China. Currently, there is still a lack of basic design method for the core mechanism (steel roll round baler) of this machine. Based on the reverse engineering (RE) principles, plane geometry, material mechanics, mechanical design, test method and ANSYS analysis method, the reserve design method for the mechanism was carried out in this paper. Next, the relationship function among the four characteristic parameters, i.e, bale chamber radius, steel roll count, steel roll radius, and clearance between adjacent steel rolls, was established based on plane geometry; the contact model between the roll and the straw core was established by theoretical analysis, and the influence law of steel roll radius on contact force between them was determined by using highspeed camera observation method and probability principle. Moreover, the highspeed camera was also reutilized to determine the correlation of the occurrences of entanglement with the clearance between steel rolls and ridges on the steel roll surface. Combined with the test results and theoretical calculations, the dimensions of the feed inlet were designed. Afterward, the mechanical model of steel roll was established, and an important component of the steel roll, i.e, the longitudinal diameter, was designed. Furthermore, the stiffness and strength of the steel roll (assembly) were validated using the Workbench module in ANSYS. According to these findings, the reverse design with DN4575 round baler model as the design objective was carried out. The results of design were as follows: steel roller radius: 75 mm, number of steel rollers: 10, clearance between steel two rollers: 10 mm, width of feeder inlet: 162 mm, steel roller long axis diameter: 20 mm, number of spoke plates: 5. In conclusion, the above reverse design process provides a systematic design method for the key parameters of steelroll round balers, which has important guiding significance for the design of steelroll round balers.

Key words:  round baler, baling mechanism, reverse engineering, reverse design, structural parameter, wrapping test