指夹式玉米免耕精密播种机的设计与试验

该文为解决北方地区播种时秸秆量大各地区种植模式差异大,传统玉米免耕精密播种机适应性差、作业效率低、开沟器易堵塞等问题,设计了指夹式玉米免耕精密播种机,分析和确定了施肥开沟器、拨草轮、玉米免耕播种单元等关键部件的结构参数。田间试验表明采用渐开线式齿形拨草轮能有效的将杂草、秸秆拨离苗带,有效防止开沟器堵塞和种子播在秸秆上的现象。在9 km/h的作业速度下,机具播种深度合格率92%,粒距变异系数9.6%,漏播指数2.5%,重播指数4.5%。一次能完成开沟深施肥、拨草整理苗带、单粒精密播种、覆土、镇压覆土作业,土壤搅动小,作业质量满足农艺要求。

Design and experiment of no-till precision planter for corn

Abstract: China is one of the main arid countries all through the world, and the percentof arid and semi-arid area is 52% of the whole country area. The farmland is exposed and becomes sandy because of the annual tillage and unreasonable cultivation, wind erosion and water erosion of the agricultural ecological losing balance, which seriously affects the agricultural sustainable development. A large number of experiments have showed that the conservation tillage technology is beneficial for the sustainable development of agriculture in north China, which can reduce the working procedure, reduce production cost, increase the content of soil organic matter, improve soil structure, and reduce soil wind and water erosion to avoid sandstorm andimprove crop yields. Different regions have different planting patterns in North China, and there is large amount of straws in the farmland when sowing. In order to solve the problem of poor adaptability, low working efficiency, easily blocked opener, and easily burnt seedlings with the vertical fertilizer of traditional seeders, the new corn no-tillage precision seeder is designed with some structure parameters of its key parts analyzed and optimized, including fertilizer opener, grass divider, sowing unit, and so on according to the references at home and abroad and the planting patterns in North China. The notched disc opener can achieve deeper fertilization near the seeds, the involutes tooth disc grass divider can separate the grass and straws, and the sowing unit can achieve the multiple works of ditching, seeding, soil covering and pressing operation at one time. The field experiment was conducted to test the operation parameters such as the seed spacing coefficient of variation, reseeding index, the leakage index, seed depth qualified index and seeder traffic ability characteristics with the speed of 6 to 12 km/h in Laishui County, Hebei Province in 2014. Its field test showed that the grass divider with involutes tooth structure can separate the grass and straws away from the seeding line, effectively protecting the opener from being blocked and avoiding seed spilled on the straw. With the speed of 9 km/h, the designed no-tillage precision seeder achieved 92% in seeding depth qualified index, the seed spacing coefficient of variation is 9.6% in seed channel, 2.5% in the leakage index, and 4.5% in reseeding index. Furthermore, the designed corn no-tillage precision seeder enables the multiple works of furrowing, deep fertilizing, dividing grass, single-seed precision drilling, burying and compacting completed at one time with low soil agitation rate and high working performance, to satisfythe corn agronomy requirement.