【摘要】 为解决免耕播种机麦茬地作业的拥堵问题,在拨抛式防堵装置的基础上提出秸秆分拨引导的防堵设计思路,设计了阿基米德螺线型防堵机构。该装置可引导秸秆攀升,实现层叠堆积,缓解秸秆平行拨离苗带时造成的秸秆局部集中,从而实现有效防堵。运用离散元分析软件EDEM 2. 7,建立了秸秆-土壤-防堵机构相互作用的仿真模型,分别对单个目标秸秆和秸秆群体进行运动追踪,验证了分拨引导和层叠堆积理念。对试验样机进行了田间性能试验和作业参数优选试验,结果表明:在播种过程中,阿基米德螺线型防堵机构作业顺畅,未发生中、重度堵塞及晾籽;防堵机构最佳工作参数为前进速度7 km/h、转速600 r/min,此时秸秆清除率最高,为92. 6%。本文设计的防堵机构性能优于前期课题组设计的防堵机构和某商品化防堵机构。更多还原

【Abstract】 The"separating-guiding"thought which utilize the anti-blocking mechanism to guide the straw to ascend and move along the rotating wheel was proposed. Based on this thought,a cleaning mechanism on account of Archimedes spiral was designed and tested. In theoretical analysis,it was found that the Archimedes spiral could guide the straw to move up along with the outline under all the forces from mechanism and other straw at the beginning of contact,later the straw obtained speed and was thrown away because of the increased centrifugal force and decreased holding force from straw. All the straw was moved in the same way and formed straw group flow,accordingly accomplished the straw shinnying and stacking. Besides,the moving behavior of straw individual and straw group were also investigated via DEM simulation. The field experiment was also done to investigate the performance of no-tillage maize planter and confirm the optimal working parameter of the Archimedes spiral anti-blocking mechanism.The experimental results showed that there were no blockage and exposed seeds. It can be inferred that the optimal working parameter of Archimedes spiral mechanism was 7 km/h of forward speed and 600 r/min of rotational speed. The mechanism designed can provide reference for the design and optimization of the anti-blocking mechanism of no-tillage maize planter.更多还原