【作者】 郝飞；

【导师】 杜健民；

【作者基本信息】 内蒙古农业大学 ， 机械制造及其自动化， 2015， 硕士

【摘要】 我国北方地区春季风大,少雨,蒸发量大,土壤风蚀严重,对于发展旱区：保护性耕作十分有必要。免耕播种不仅可以增肥保墒,减少风蚀,而且可以达到增产、增收、节约成本的目的；然而免耕作业环境恶劣,土壤坚实度大,地表平整度差,且覆盖大量的秸秆残茬,使得单体作业起伏频繁,播种深度的平稳性受到影响。若使播种深度平稳一致,则需选择合理的仿形机构,以及最优的结构参数。本文以仿形机构为研究对象,以播种深度平稳性为依据,以寻求仿形效果最优的结构参数为目的。通过对播种单体关键零部件的选择和尺寸确定,以确定单体的结构和设计参数；利用Pro/E软件的参数化设计功能,对零件进行三维实体建模并装配免耕播种单体；利用ADAMS软件对建立的免耕播种单体的平行四杆仿形机构进行运动仿真模拟试验,对比分析不同仿形结构参数的数据曲线,得出仿形最优杆长尺寸参数。对于本设计免耕单体采用侧位仿形方式,杆长范围在450～500mm之间,仿形效果达到最优。通过田间试验,以播种深度稳定性为判定依据,验证仿真试验结果的正确性。以优化前杆长420mm和优化后杆长460mm作为对比进行田间试验。结果表明：杆长优化前后两种仿形情况下,平均播种深度相差仅为1.09mm,但在杆长460mm仿形情况下,平均播深稳定系数达90.15%,而杆长42’0mm仿形情况下,平均播深稳定系数为81.85%,优化后播深稳定性得到较大的提高,田间试验与仿真试验结论相一致。更多还原

【Abstract】 The wind is strong, the drought, highly evaporation and wind erosion is serious in spring in northern China. It is necessary to set up conservation tillage technology. The no-tillage technology not only makes soil fertility and soil moisture conservation, improves wind erosion, but also achieves the purpose of increasing production and saving cost. Because of the environment of no-tillage work is terrible, such as hard soil, poor surface flatness and covering a lot of straw stubble, such a case cause the monomer of no-tillage seeder works on frequent ups and downs, so affect the stability of sowing depth. Ensure the stability of sowing depth, there need reasonable profiling mechanism and the best structural parameters.In this paper, research influence of profiling mechanism on the stability of sowing depth, seeking to the best structural parameters of profiling mechanism. By selecting key parts of the monomer and determining size, determine the monomer design scheme and structural parameters. By using parametric design function of Pro/E software to establish three-dimensional solid model and assembling the monomer of no-tillage seeder; and used ADAMS software to finish the simulation test of parallel four-bar no-tillage seeding monomer profiling mechanism what had been built, Comparatively analyzed Data curve of different structure of profiling mechanism, obtain the optimum rod length size parameters of profiling mechanism.By field experiment, determining the basis is the stability of sowing depth, verify the correctness of simulation results. By Contrasting rod length 420mm of before optimization and rod length 460mm of after optimization finish field experiment. The results showed that:both before and after optimized the rod length profiling cases, the average sowing depth only is 1.09mm, but after optimized the rod length 460mm profiling cases, the stability factor of average sowing depth is 90.15%, before optimized the rod length 420mm profiling cases, the stability factor of average sowing depth is 81.85%, after optimization the stability of sowing depth is greatly improved, the field experiment is consistent with the simulation test results更多还原