气力式杂交稻精量穴直播排种器设计与试验

Design and Experiment of Pneumatic Precision Hill-drop Drilling Seed Metering Device for Hybrid Rice

为实现杂交稻大田精量穴直播,解决杂交稻直播时因芽种流动性差和细长形状造成种箱中芽种架空或堵塞的问题,设计了一种气力式杂交稻精量穴直播排种器。阐述了其基本结构和工作原理,分析了梳种条对芽种的助吸作用;研究了充种区芽种的受力情况,建立了芽种不同姿态被吸附时吸室真空度方程。试验研究了有无梳种装置,排种盘转速以及排种盘群组吸孔直径、排种盘转速、吸室真空度3因素综合作用对排种性能的影响。试验结果表明:梳种条对芽种起到搅动、梳理作用,有利于提高排种器的充种性能;当排种盘转速为15 r/min,吸室真空度为3.5 k Pa,排种盘群组吸孔直径为1.6 mm时,气力式杂交稻排种器的排种性能最好,其合格率为86.5%。田间试验结果表明,排种器田间播种能够满足杂交稻大田精量旱穴直播的农艺要求。

Paddy rice is one of the most important fine food crops that feed the largest proportion of the world＇s population. There are two planting patterns of paddy rice called direct seeding and transplanting.In order to realize precision hill direct seeding of hybrid rice in field and solve the problem of budded seed overhead and jaming in seeding box,a pneumatic seed metering device for hybrid rice budded seed was designed based on the seeding principle of air suction-air blowing. The seed metering device used cam,pushing rod and combing strips to solve the problem of rice budded seeds＇ mobility. The seeding plate which had groups of suction holes could absorb 2 - 4 rice budded seeds. The seed metering device was constituted by seed box,cam,push rod,seeding axis,seeding plate,air chamber,flange and so on,by which two to four bud seeds could be sucked and dropped at the same time. The adsorption mechanism of budded seed in seed filling area was analyzed in the paper theoretically. An equation of vacuum degree in suction chamber was built. The paper launched bench experiment of double-sided pneumatic seed metering device and studied the relationship between seeding performance and combing device,rotational speed of seeding plate. The orthogonal experiment was done which took the diameter of suction hole,rotational speed of seeding plate and vacuum degree of air chamber as factors. The experiment result showed that the combing strips could stir rice budded seeds. The orthogonal experiment indicated that the optimal condition for the seed metering device is as follows： when the rotational speed is 15 r / min,the vacuum degree is 3. 5 k Pa and the diameter of suction hole is 1. 6 mm. And the experiment in field indicated that the device meets the agronomic requirement of planting rice budded seed.