免耕播种机锯切防堵装置设计及其切割机理的研究

    Design of sawing anti-blocking mechanism for no-tillage planter and its cutting mechanism

    • 摘要: 针对我国北方旱地一年两熟地区免耕播种机堵塞现象和已有主动式防堵装置转速高(1500 r/min以上)、功耗大(单位幅宽达16~41.74 kW/m,含牵引功率)的现实问题,设计了一种新型免耕播种机锯切防堵装置,分析了该装置的切割机理,应用有限元ANSYS软件计算了锯齿圆盘切刀的应力分布,得出了锯齿圆盘切刀用于玉米秸秆切割的可行性。土槽试验表明:1)该装置采用逆转式作业,兼有无支撑和有支撑两种切割方式,切割彻底,并能借助刀齿前角和抛撒板将已切断秸秆定向抛送到开沟器后方,实现了切割、定向抛撒一体化功能;2)秸秆切碎率随转速和秸秆含水率的增大而增大,秸秆含水率高时有利于提高切割质量;3)秸秆切碎率在动定刀间隙一定时,随前进速度增大而降低,小间隙时无漏切和撕皮现象,切割质量高,功耗小。理论和试验结果表明:与其他主动式防堵装置相比,锯切防堵装置具有良好的切割性能,其转速低(650 r/min)、功耗小(单位幅宽为2.95 kW/m)、秸秆覆盖量适应性强,为改善免耕播种机防堵性能提供了一条新途径。

       

      Abstract: Based on blocking issues of no-tillage planter for dry-land farming in two-crop-a-year region in North of China and shortcomings of anti-blocking mechanism developed, such as higher rotation speed (above 1500 r/min) and bigger power consumption (width power consumption per unit up to 16~41.74 kW/m, including traction power), a new sawing anti-blocking mechanism was developed and its cutting mechanism was investigated in this paper. Meanwhile stress distribution of the saw-tooth blade calculated by the ANSYS finity element software showed that the saw-tooth blade would be feasible to cut corn straws. Experimental results in the soil bin showed that: 1)The sawing anti-blocking mechanism with two cutting modes of sustaining and no-sustaining cut could realize an integrated function of cutting and directly throwing by reverse rotation, namely, it could throw straws directly to the rear of the opener by former angle of saw-tooth and thrower; 2)The cutting rate of straws would increase along with the rising of straw moisture and rotation speed, and higher moisture of straws would be of benefit to improving cutting quality; 3)The cutting rate of straws would decrease along with the rising of velocity of vehicle while interval of the moved and fixed blade was determined. And the sawing anti-blocking mechanism had higher cutting quality and lower power consumption without leaky cutting and tearing out with small interval of the moved and fixed blade. Compared with other driving anti-blocking mechanisms, theoretical analysis and experimental results showed that the sawing anti-blocking mechanism had fine cut capability and lower rotation speed (650 r/min) and lower power consumption (power consumption per unit width up to 2.95 kW/m) as well as stronger suitability to different stubbles mulch. Additionally, a new way was found out to improve anti-blocking performance of no-tillage planter.

       

    /

    返回文章
    返回