秸秆后覆盖小麦播种机设计与试验

针对华北平原麦-玉两熟区,小麦在玉米秸秆覆盖地撒播易出现秸秆堵塞、麦种架空、晾籽等问题,利用正转旋耕抛土模型以形成土壤、秸秆顺序覆盖,设计了一种秸秆后覆盖小麦播种机,可一次完成旋耕、均匀撒播、覆土、覆盖秸秆、镇压等作业。旋耕刀采用对称螺旋线排列;通过抛土运动分析确定了被抛物料运动的最大高度为0.52 m,水平方向最大位移为0.79 m,并确定了导土板的位置参数;通过性能试验优选分种装置与水平方向夹角为35°,分种板间的距离为50 mm。在河北涿州试验站进行了整机田间试验,结果表明:正转旋耕装置能有效抛土、抛秸秆,避免秸秆、根茬堵塞分种装置,耕深稳定在148~152 mm内,耕深稳定性系数为95.5%,多功能行走轮滑移率约为5.3%,机具通过性能符合国家标准(GB/T 20865—2007)要求;机具作业后秸秆覆盖量平均为1.07 kg/m2,达到作业前秸秆覆盖量的80%;播深稳定在30~35 mm内,播深合格率为91.1%,不同位置幅宽内10 cm×25 cm矩形框内麦种数量稳定在29~30粒,符合农艺要求。

Design and Experiment on Straw Post-covering Wheat Planter

In the wheat-maize rotation area of North China Plain, it is widely recognized that there are some problems in the wheat broadcast sowing under the condition of the maize straw mulching, such as straw blockage and wheat seeds planted on the maize straw. In order to solve these problems, taking advantage of the soil-thrown model of down-cut rotation tillage to form soil and straw sequential cover, a straw post-covering wheat planter was designed, which could implement the following function at one time: rotary tillage, uniform-broadcast sowing, anti-blocking, covering soil and straw and compacting. The planter included the following nine parts: suspension frame, gearbox, rotary tillage device, soil-oriented plate, seed-dividing device, soil-straw separation device, multifunctional ground wheel, frame, seeding device, and so on. The layout of rotary blades was symmetrical helix arrangement, and the maximum height of the thrown granule was calculated as 0.52m, the maximum displace in the horizontal direction was 0.79m, and the position parameters of the soil-oriented plate were determined. By means of the performance test, it was preferable that the distance between the seeding-dividing device and the horizontal direction was 35° and the distance between the seed-dividing plates was 50mm. The planter field experiment was conducted in Zhuozhou Experimental Station of Hebei Province, China. And the results indicated that the down-cut rotary tiller could effectively throw the soil and straw and avoid maize straw blockage. The depth of tillage was around 148~152mm, the stability coefficient of tillage depth was 95.5%, slip rate of multi-function walking wheel was about 5.3%, the passing ability of the planter was good and the performance can meet national standards;the weights of maize straw was 1.07kg/m2 after sowing, which can reach 80% of straw amount before sowing;the depth of sowing was around 30~35mm, sowing pass rate was 91.1%, the mean number of wheat seeds in the rectangular frame of 10cm×25cm in different positions was around 29~30, which met the agronomic requirements.