摆动夹取式玉米精量排种器设计与试验

针对玉米种子三轴尺寸差异大,在取种过程中易造成漏取和重取的问题,设计了一种摆动夹取式玉米精量排种器,阐述其结构组成及工作原理,并对关键部件进行设计;通过建立的模型进行力学和运动学分析,得到了影响排种器取种性能的关键因素;通过EDEM软件建立仿真模型,分析种群高度及排种器转速对种群流转速度的影响规律,得到了排种器取种性能曲线;以取种块开合角、进种筒安装高度、排种器转速为试验因素,取种单粒率、漏取率、重取率为评价指标进行二次正交旋转组合仿真试验,结果表明最优参数组合为取种块开合角43.87°、进种筒安装高度37.84 mm、排种器转速0.41 r/s,在最优参数组合下进行排种性能台架验证试验,得到排种器排种合格指数为94.11%、漏播指数为2.52%、重播指数为3.37%,满足行业标准及农艺要求,研究结果为机械式玉米精量排种器关键部件的设计优化提供了理论参考。

Simulation and Experiment of Seed Taking Performance of Swing-clamp Type Maize Precision Seed-metering Device

In response to the problem of large differences in size of three axes of maize seeds, which are prone to omission and re-taking during seed picking, a swing-clamp type maize precision seed metering device was designed, its structure and working principle were introduced and analyzed, and the key components were designed. The key factors affecting the seed extraction performance of the seed-metering device were obtained by establishing mechanical and kinematic models for analysis. The simulation model was established by EDEM software to further analyze the influence law of population height and seed-metering device''s rotational speed on population flow speed, and the seed-metering device''s fetching performance curve was obtained. The seed picking block opening and closing angle, seed feeding cylinder installation height and seed-metering device''s rotation speed were used as experimental factors, and the single seed picking rate, leakage rate and multiple picking rate were used as evaluation indexes for the secondary orthogonal rotation combination simulation test, the results showed that the optimal combination of parameters was 43.87°of seed picking block opening and closing angle, 37.84mm of seed feeding cylinder installation height and 0.41r/s of seed-metering device''s rotational speed. Under the optimal combination of parameters, the seed row performance bench validation test was conducted, and the seed row qualification index of the seed rower was 94.11%, the missed seed index was 2.52% and the reseeding index was 3.37%, meeting the industry standard and agronomic requirements. The research result provided a theoretical reference for the design optimization of different working area components of the mechanical corn precision seed-metering device.