大葱联合收获机设计与试验

Design and Experiment of Green Onion Combine Harvester

摘要:

为解决大葱收获阶段挖掘易拥堵、损伤大等问题，本文确定集挖掘、抖土、夹持和输送工序为一体的收获方案及工作原理，设计一种适应垄作种植模式的大葱联合收获机。机具采用旋耕刀与挖掘铲组合的挖掘机构，通过旋耕刀切割和抛送，去除葱垄大部分多余土壤，可有效降低挖掘铲作业时挖掘阻力；采用偏心式抖土机构，可有效解决壅土问题；采用扭转机构，便于后续大葱铺放。借助理论分析及仿真试验，确定了挖掘、抖土、夹持输送等关键机构结构及参数。以损伤率、含杂率、损失率为试验指标，以偏心轮转速、抖栅振幅及夹持带倾角为试验因素进行三因素三水平正交试验设计，优化参数得到最优参数组合，并通过田间试验验证，试验结果表明：当偏心轮转速为295 r/min、抖栅振幅为28 mm、夹持带倾角为38°时，自走式大葱联合收获机损伤率为1.41%、含杂率为3.02%、损失率为0.44%，满足大葱低损机械化收获要求。

Abstract:

Aiming to address the problems of easy clogging and high damage rate during the digging process of green onion harvesting, a harvesting scheme integrating digging, soil shaking, clamping and conveying processes and its working principle were determined, and a combined green onion harvester adapted to the ridge cultivation mode of green onions was designed. The machine adopted a digging device combining rotary tillage blades and a digging shovel; the rotary tillage blades cut and threw soil to remove most of the excess soil from green onion ridges, which can effectively reduce the digging resistance of the digging shovel during operation. An eccentric soil shaking mechanism was employed to effectively solve the soil accumulation problem, and a torsion mechanism was designed to facilitate the subsequent laying of green onions. Based on theoretical analysis and simulation tests, the structures and parameters of key devices such as the digging, soil shaking, clamping and conveying devices were determined. Taking damage rate, impurity rate and loss rate as the test indexes, and the rotational speed of the eccentric wheel, the amplitude of the soil shaking grid and the inclination angle of the clamping belt as the test factors, a three-factor and three-level orthogonal test was designed to optimize the parameters and obtain the optimal parameter combination, which was then verified by field tests. The test results showed that when the rotational speed of the eccentric wheel was 295 r/min, the amplitude of the soil shaking grid was 28 mm and the inclination angle of the clamping belt was 38°, the damage rate, impurity rate and loss rate of the self-propelled combined green onion harvester reached 1.41%, 3.02% and 0.44%, respectively, which met the requirements of low-damage mechanized harvesting of green onions.