秸秆覆盖地少耕播种机的设计与研究

发布时间：2018-10-21 08:08

【摘要】：近年来,东北地区作为我国重要粮食生产基地,为确保东北地区农业长期稳定发展,正大规模实施农业保护性耕作技术推广。免耕和少耕是实施保护性耕作的核心。免耕播种技术的推广和普及,在很大程度上提高了农业生产效率。但随着免耕播种机快速发展,免耕播种机也暴露出一些不容忽视的问题。首先,秋收后,地表秸秆覆盖量增加,在播种作业时,免耕播种机容易出现缠堵现象,给机具的通过性带来困难;其次,由于免耕播种动土量少,种床土壤不松软,一定程度上阻碍了苗期作物的生长;再次,免耕播种采用留茬、垄侧开沟,不益于下茬作物的播种和管理。基于以上问题,在查阅大量国内外免耕播种机研究现状的基础上,并且根据东北地区秸秆覆盖地玉米播种的作业条件和农业技术要求,研制了一种新型的保护性耕作条件下少耕播种机,并对整机及其关键部件进行了系统的理论分析和试验研究。本文的研究内容及取得的成果如下:1)整机结构设计:少耕播种作业由动力开沟和常规播种两个环节组成,同样,机具总体结构设计也分成两部分,即破茬单体和播种单体。通常,破茬机是全垄、全幅作业,不符合少耕要求,设计时,将单垄灭茬刀盘总成的五个刀盘减为两个,两盘横向间距100mm,实现了少耕,改变刀具排列与分布,改善根茬打碎效果;播种施肥装置为适应东北地区的耕地特点,保证播深一致性,保留了四连杆仿形,经动力开沟后,播种带土壤比较松软,因此,施肥和播种开沟器均采用滑刀式开沟器。滑刀对土壤扰动小,又能有效防堵、防缠,改善机具的通过性能。镇压轮同时又是排种器的动力轮,考虑到作业条件恶劣,动力传动采用锥齿换向机构。2)样机试制:通过大量的理论分析和试验研究,确定了“2BS-2型”少耕播种机各关键部件的结构与参数,根据机械设计原理,并结合农业机械设计手册,完成了第一代样机的试制。3)田间试验:于2016年5月在试验田进行秸秆覆盖地少耕播种机整机试验,分别验证了少耕播种机的破茬防堵性能、播深一致性、地轮的滑移率、播种的合格率、漏播率和重播率。试验表明,该机具有较好的破茬能力。
[Abstract]:In recent years, as an important grain production base in our country, the northeast region is carrying out large-scale agricultural conservation tillage technology extension in order to ensure the long-term and stable development of agriculture in Northeast China. No tillage and less tillage are the core of conservation tillage. The popularization and popularization of no-tillage seeding technology, to a large extent, improve the efficiency of agricultural production. However, with the rapid development of no-tillage planter, no-tillage planter also exposed some problems that can not be ignored. First of all, after autumn harvest, the amount of straw mulch on the surface increases. During sowing, the no-tillage planter is prone to the phenomenon of entangle and clogging, which makes it difficult for the machine to pass. Secondly, because of the small amount of no-tillage seeding and soil movement, the soil of the planting bed is not soft. Thirdly no-tillage seeding with stubble ridge and side furrow is not beneficial to the sowing and management of the next crop. Based on the above problems, on the basis of consulting a large number of domestic and international research status of no-tillage planter, and according to the operating conditions and agricultural technical requirements of corn seeding in the field of straw mulch in Northeast China, A new type of planter with less tillage under the condition of conservation tillage was developed, and the theoretical analysis and experimental study of the whole machine and its key parts were carried out. The research contents and results obtained in this paper are as follows: 1) the whole machine structure design: the less tillage seeding operation consists of two links: power trench and conventional seeding. Similarly, the overall structure design of the machine is also divided into two parts, that is, stubble breaking monomer and seeding monomer. In general, the stubble breaker is a full ridge, full width operation, which does not meet the requirement of less tillage. In the design, the five cutters of a single ridge stubble cutter assembly are reduced to two, and the transverse spacing between the two disks is 100 mm, which realizes less tillage and changes the arrangement and distribution of the cutting tools. In order to adapt to the characteristics of cultivated land in Northeast China and ensure the consistency of sowing depth, the four-bar profile is retained, and the soil in the seeding zone is relatively soft after dynamic trenching. Both fertilization and seeding trench openers adopt sliding knife trench openers. Skidding knife has little disturbance to soil, and can effectively prevent plugging and entrainment, and improve the passing performance of machine and tools. The repressing wheel is the power wheel of the metering device at the same time. Considering the bad working conditions, the power transmission adopts the conical gear commutating mechanism. 2) the prototype is trial-produced: through a large number of theoretical analysis and experimental research, The structure and parameters of the key parts of the "2BS-2" less tillage planter are determined. According to the principle of mechanical design, and combined with the design manual of agricultural machinery, The trial production of the first generation prototype was completed. 3) the field experiment was carried out in the experimental field in May 2016. The results showed that the stubble blocking performance, the consistency of sowing depth and the slip rate of the ground wheel were verified respectively. The qualified rate of seeding, the rate of missing seeding and the rate of replanting. The test shows that the machine has better stubble breaking ability.
【学位授予单位】：吉林农业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：S223.2

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