负压式谷子穴播排种器设计及正交试验研究

Design and Orthogonal Test of Vacuum Millet Hill-drop Seed-metering Device

谷子的机械条播方式不仅浪费种子,且需要人工间苗,用工成本高。为解决此难题,设计了一种负压式谷子穴播排种器,排种盘的吸种孔采用组孔的结构形式。通过JPS-12排种器综合试验台对谷子排种器进行了正交实验,采用三因素三水平试验方案,运用极差分析和方差分析得出了排种盘吸种孔径、排种器转速和气室负压值对穴粒数合格指数、穴距合格指数、空穴指数及穴距变异系数的影响显著水平。确定了各因素最优组合:吸种孔径2.0mm、气室负压值-0.8k Pa、排种器转速30r/min。优化定型后排种器的综合试验性能指标分别为:穴粒数合格指数86.67%,穴距合格指数89.33%,空穴指数1.33%,穴距变异系数13.74%,符合谷子精量穴播及农艺要求。

Traditional mechanical drilling method for millet not only wastes millet seeds,but also needs higher-cost artificial thinning. In order to solve the problem,a negative pressure style precision hill-drop millet seed-metering device was designed to seed coated millet. Suction-holes in the seed-metering plate are the structure of group holes. Air-suction holes of seed-metering plate adopt holes group structure style. Orthogonal test was implemented on the JPS-12 seed-metering device test bench,which was three factors and three levels test scheme. The influence significant of the diameter of air-suction holes,rotational speed and negative pressure value in the air chamber on qualified index of seeds number per hole,qualified index of holes distance,index of empty holes and variation coefficient of holes distance was gained by the range analysis and variance analysis. Then optimal combination of various factors was defined,that was 2.0 mm diameter of air-suction holes,-0. 8 k Pa negative pressure value and 30 r/min rotational speed. Synthesis test performance indexes of optimized seed-meeting device separately are 86. 67% qualified index of seeds number per hole,89. 33% qualified index of holes distance,1. 33% index of empty holes and 13. 74% variation coefficient of holes distance. These indexes value meet precision hill-drop of millet seed and agronomic requirements.