气吸机械复合式大豆精密排种器设计与试验  

Design and Experiment of Pneumatic-mechanical Combined Precision Metering Device for Soybean

作　　者：贾洪雷[1,2] 陈玉龙 赵佳乐[1,2] 王佳旭[1] 郭明卓 庄健[1,2] JIA Honglei;CHEN Yulong;ZHAO Jiale;WANG Jiaxu;GUO Mingzhuo;ZHUANG Jian(College of Biological and Agricultural Engineering, Jilin University, Changchun 130025, China;Key Laboratory of Bionic Engineering, Ministry of Education, Jilin University, Changchun 130025, China)

机构地区：[1]吉林大学生物与农业工程学院,长春130025 [2]吉林大学工程仿生教育部重点实验室,长春130025

出　　处：《农业机械学报》2018年第4期75-86,139,共13页Transactions of the Chinese Society for Agricultural Machinery

基　　金：国家重点研发计划项目(2017YFD0700701);国家自然科学基金项目(51705194);吉林省科技发展计划项目(20160307011NY)

摘　　要：针对现有气吸式高速精密排种器遇负压骤降时易发生大量漏播的技术难题,设计了一种在排种盘上同时设有吸孔、导种槽和取种槽3种种子拾取机构的气吸机械复合式大豆精密排种器,其中导种槽引导种子向取种槽运动,取种槽拾取种子,同时吸孔产生吸力促进种子的拾取,通过3种拾取机构共同改变种群运移行为,保证气流负压骤降情况下的排种性能;通过离散元仿真设计和理论建模分析等方法,研究关键设计参数对种群运移规律的影响,并对关键部件几何结构参数进行优化设计;通过回归分析和多因素试验得出作业速度、取种槽和导种槽几何结构尺寸、负压均对排种器播种效果有显著影响,并得出排种器最优结构参数为:导种槽倾角45°、导种槽深度2 mm、取种槽上边宽度9.5 mm、取种槽下边宽度7.3 mm、取种槽深度5.7 mm、取种槽前后槽面宽度9.5 mm,在该几何结构条件下,当作业速度不大于8.6 km/h、负压不小于1.6 k Pa时,播种粒距合格率不小于95%;通过排种器的田间验证试验,最优结构参数条件下该排种器播种粒距合格率为93.67%、重播率为3.32%、漏播率为3.01%;通过台架对比试验得出当负压降至1.1 k Pa时,该排种器相较于勃农气吸式排种器和MASCHIO气吸式排种器,粒距合格率分别提高6.48、1.92个百分点,当负压降至0.6 k Pa时,粒距合格率分别提高9.12、4.25个百分点。Seeding absence caused by negative pressure drops is a major technical problem in pneumatic precision metering device. A novel design of a soybean precision metering device was presented, which was compatible with pneumatic and mechanical combination, that consisted primarily of a plate, a covering, a shall and a shaft. The plate of the pneumatic-mechanical combined seed metering device had three seed picking institutions, suction hole, guide groove and pickup hole. To ensure seeding performance in the case of negative pressure drops, three institutions worked together to change the movement of soybean seed. The discrete element simulation software EDEM was used to simulate to optimize the geometric structure parameters of the guide groove, and the Hertz - Mindlin no-slip contact model was selected for the simulation. Seed speed, seed number and miss filling rate were used as test indexes for the simulation. The optimal angle and depth of the guide groove were 45° and 2 mm, respectively. The soybean seeds of Jiyu 302, which was widely adopted in Jilin Province, were used as an object of indoor bench test and field trial. The indoor bench test was carried out on a JPS - 12 test bench, which was widely used to research the performance of seed metering device. Seed hole size, forward speed and negative pressure were chosen as test factors. Qualified rate, multiple rate and missing rate were used as test indexes. The variance analysis, as well as regression analysis of the test data, was carried out by Matlab software. The results showed that seed hole size, forward speed and negative pressure significantly affected the seeding performance. The optimal geometric parameters of the seed metering device were as follows ： the up edge width of the seed hole was 9.5 ram, the width between front and back face was 9.5 mm, the below edge width and depth was 7.3 mm and 5.7 mm, respectively. With those optimal geometric parameters, the qualified rate of the pneumatic-mechanical combined seed metering device was no less than

关 键 词：大豆精密排种器 气吸机械复合式 离散元分析 试验 回归分析 

分 类 号：S233.23[农业科学—农业机械化工程]