三七压穴精密排种装置设计与试验

Design and Experiment of Precision Seeding Device for Hole-drop Planter for Panax notoginseng

三七播种株行距均为5 cm左右,属于密集精密播种,为实现三七高密度精密播种,克服开沟易堵塞的难题,设计了一种三七压穴精密排种装置。阐述了三七压穴精密排种装置的工作原理,确定了其主要结构参数,以云南省文山市三七种子为研究对象,采用二次旋转正交组合试验方法,对排种装置进行排种性能试验,选取压穴柱直径、前进速度、投种点到压穴点水平距离为试验因素,建立了合格指数、漏播指数、重播指数、各行排量一致性变异系数的数学模型,分析了各试验因素交互作用对合格指数的影响规律。结果表明,影响合格指数的因素主次顺序为:压穴柱直径、投种点到压穴点水平距离和前进速度。通过参数优化,确定了最优参数为压穴柱直径24. 5～29. 5 mm、投种点到压穴点水平距离330 mm、前进速度0. 44～0. 61 m/s,此时合格指数大于90%,漏播指数小于5%,重播指数小于5%。经2BQ-15型三七精密播种机整机试验可知,作业速度为0. 35 m/s时,播种机合格指数最高为93. 5%,满足三七播种要求。

Panax notoginseng is mainly grown in Yunnan Province. The row spacing and plant spacing of the seedlings of Panax notoginseng are about 5 cm. In order to achieve high-density precision seeding of Panax notoginseng ,overcome the problem of easy blockage of trenching,a hole precision seed-metering device was designed. The main structure and the working principle of the metering device were expounded. The key structure parameters were determined through theoretical calculation according to planting requirements. According to the extensive testing combined with the experimental results of relevant scholars,the main factors which affected seeding performance of hole-drop planter precision seed-metering device were determined,which were pricking hole column diameter,forward velocity and dropping seeds point to the pricking hole roll distance. The Panax notoginseng seeds in Wenshan were chosen for sowing object. Based on the three-factor five-level quadratic orthogonal rotating combination test method, the influences of pricking hole column diameter,dropping seeds point to the pricking hole roll distance and forward velocity on sowing performance were explored. The experimental results showed that the influence of negative pressure on the qualified rate was very significant ( P <0.01). Based on the results of examination,it was found that the fitting of the equations was good,the best parameter combination was pricking hole column diameter of 24.5~29.5 mm, forward velocity of 0.44~0.61 m/s and dropping seeds point to the pricking hole roll distance of 330 mm, and under the optimal condition,the qualified index was more than 90%,the missing index was less than 5% and the multiple index was less than 5%. The hole-drop planter precision seed-metering device met the standard and requirements by comparing the results with the national standard and Panax notoginseng planting requirements. Field experiments were conducted to examine the performance of 2BQ 15 type precision planter for Panax notoginseng ,the qualified index of the plantor was up to 93.5%,when the operating speed was 0.35 m/s. The results indicated that precision seeding device for hole-drop planter can meet the requirements of Panax notoginseng seeding.