玉米灭茬起垄施肥播种机的设计与试验

东北春玉米采用垄上播种,整地与播种过程分开,机器进地次数多、播种对行难度大、播种过程易破坏垄形,为解决此问题,该文研制了玉米灭茬起垄施肥播种机。该文对复式起垄和播种的作业过程进行了理论分析,通过经验设计和理论计算确定了中间连接装置、灭茬机构和播种单体的结构形式和参数,对起垄机构进行了基于受力计算的有限元应力分析,对整机的动力配备和稳定性进行了理论分析。样机田间试验结果表明,该机根茬粉碎率为88.2%,起垄垄形规则,垄高、垄顶宽、垄间距合格率分别达到95%、90%和90%,播种效果较好,粒距合格指数92%,种、肥深平均为56.22和114.36 mm。该机各参数满足农艺要求,为垄上播种的耕播联合作业提供了参考。

Design and experiment on maize stubble cleaning fertilization ridging seeder

Abstract: Maize is one of the main crops in the Northeast China. The agronomic requirement of maize planting in this region is stubble cleaning and ridging before sowing. Stubble cleaning can crush crop straw, which could promote the growth speed of maize and increase the organic matter content in soil. Ridging can increase the surface area of the land, which is beneficial for improving the soil temperature. Transverse ridge can hold water from flowing away. High ridge can avoid the submergence of corn. Side deep fertilizing can supply abundant nutrient for maize seedlings, increase root length, and improve seedling growth. Most maize-growing regions in the Northeast China use small four-wheel tractors to clean stubble and ridge, and sow on the ridge with small seeders. As for the above model, the multiple field operations are needed, which always break the physical structure of soil, disturb soil layer and even lead to water consumption with low mechanical efficiency. The existing combined machines can not ridge and sow together, resulting in ridge damage and difficulties in row-follow. In terms of this problem, there is hardly combined equipment to fulfill the above tasks. In order to solve problems mentioned above, this paper designed 2BYMQF-4 maize stubble cleaning fertilization ridging seeder, which was suitable for the agronomic requirement (cleaning stubble, ridging, fertilizing and sowing in one time) in the Northeast China. By researching multiple ridging method, theoretical analysis of ridging and sowing was made by this paper. The multiple ridging method of this machine was divided into 5 steps: stubble cleaning and small ridging after rotary tillage; ditching, fertilizing and seed dropping; covering soil by double disks; hilling with ploughshare and compacting with broad width flexible compacting roll. This paper described the overall design of the machine, and determined the structure parameters and the working parameters of the main parts, such as the connecting mechanism, stubble cleaning device, sower unit and ridging device. The paper also described the working principles of the parallel quadrilateral adaptive connecting mechanism and the compensated suspension mechanism, as well as the mechanical structure and working principles of the precision planter unit, analyzed the stress under ideal condition by theoretical calculation, and made the finite element static force analysis of the ploughshare according to the calculation results. The paper calculated the power consumption of the track equipment and the power take-off shaft to analyze the power disposition, and analyzed longitudinal stability of the tractor mounted implement based on virtual prototype technology. According to this operation method, researchers made the test program and test method of maize stubble cleaning, ridging, fertilizing and seeding machine, and also carried out the field experiment on this machine based on the program and test method. Field experiment indicated that stubble crushing ratio reached 88.2% at the conventional working speed. The qualified rates of the ridging height, the width of ridging top and the distance between ridging rows were respectively 95%, 90% and 90%. The pass rate of average grain distance was over 92%, with the standard deviation of 43.65 and the coefficient of variation of 5.24. The average depths of seeds and fertilizer were respectively 56.22 and 114.36 mm, with the coefficients of variation of 10.07 and 10.28. The machine has the advantages of combined operation in maize stubble cleaning, ridging, fertilizing and seeding, such as simple operation, reasonable structure, safe and reliable work as well as high operation efficiency, which meets the design requirements.