Authors

Abstract

In order to improve the sowing performance of air-pressure maize dense planting high-speed precision seed-metering device and reduce the occurrence of multiple and missed seeds phenomenon, a seed-cleaning mechanism with progressive seed scraper was designed. The structure and working principle of the seed-metering device and seed-cleaning mechanism are described, the mechanical model before and after the excess seed enters the seed cleaning area is established, and the design parameters of the key components of the seed-cleaning mechanism are determined through the method of theoretical analysis. The experiments of single-factor and multi-factor are conducted with seed clearing angle, operating speed, positive pressure value of blower as influencing factors, and with qualified index, miss index, multiple index as the experimental indexes. The results show that the optimal seed-clearing performance parameter combination of the seed-cleaning mechanism is seed-clearing angle of 0.024°, operating speed of 10 km/h, positive pressure value of 6.0 kPa, verification test of the parameter combination of the qualified index of 98.11%, multiple index of 1.44%, miss index of 0.45%. In the comparative experiment, the qualified index of the device with seed-cleaning mechanism increased by about 2.3% compared to the device without seed-cleaning mechanism, and the multiple index decreased by about 2.2%. The seed-cleaning mechanism is reasonably designed to meet the seed clearing operation requirements of air-pressure maize dense planting high-speed precision seed-metering device.

Abstract in Chinese

为提高气压式玉米密植高速精量排种器的播种作业性能，减少漏播、重播现象的发生，设计了一种带有递进性刮种刀的清种装置。阐述了排种器、清种装置的结构与工作原理，建立了多余种子进入清种区前后的力学模型，得到了风机正压值与作业速度是影响清种装置清种性能的主要因素，通过理论分析的方法确定了清种装置关键部件的设计参数。以清种角度、作业速度、风机正压值为影响因素，以粒距合格指数、重播指数、漏播指数为试验指标进行了单因素试验，确定了合理的因素变化范围进行了多因素试验，得到了清种装置的最佳清种性能参数组合并对其进行了试验验证以及对比试验。结果表明，清种装置最优清种性能参数组合为清种角度0.024°、作业速度10km/h、风机正压值6.0kPa，验证试验该参数组合的合格指数为98.11%、重播指数1.44%、漏播指数0.45%，对比试验中带有清种装置的排种器较无清种装置的排种器合格指数提高了2.3%左右，重播指数降低了2.2%左右，清种装置设计合理可满足气压式高速密植精量排种器对清种装置的清种作业要求。