轮勺式大蒜单粒取种装置设计与试验

Design and Experiment of Wheel-spoon Type Garlic Precision Seed-picking Device

针对因大蒜颗粒大、形状不规则和表面粗糙而造成漏播及重播率高的问题,设计了一种轮勺式大蒜单粒取种装置,该装置主要由取种勺、取种轮、驱动电机、支架、种箱等组成。对取种区、输种区和排种区的大蒜分别进行了受力分析,阐述了轮勺式大蒜单粒取种装置的原理,通过离散元仿真软件对取种勺及取种轮的结构形状进行了对比优化,确定了取种勺及取种轮的最优结构,采用数理统计的方法确定了取种勺的尺寸区间。以取种勺的半径、长度和取种轮转速为试验因素,以漏充率和合格率为响应指标进行了正交回归试验,建立了漏充率和合格率的回归模型,对回归模型进行了参数优化。最优参数组合为取种勺半径16.30 mm、取种勺长度38.50 mm、取种轮转速10.0 r/min,在最优参数组合下进行了台架试验,得漏充率5.50%,合格率91.10%,与回归模型预测结果基本一致。

Due to large grain size,irregular shape and rough surface of garlic seeds,the missed sowing rate and reseeding rate are high.Aiming to mitigate these problems,a wheel-spoon type garlic seed metering device was designed,which was mainly composed of seed scoop,seed taking wheel,driving motor,bracket and seed box.The stress analyses of garlic seeds in seed taking zone,transferring zone and discharging zone of the device were carried out.The optimal structures of spoons and wheels after comparing the structural shapes of different types of spoons and wheels via discrete element simulation analyses were determined.The size of seed scoop was statistically determined.The orthogonal regression test was performed,treating the radius of seed scoop,the length of seed scoop and the rotation speed of seed wheel as test factors,and the rate of missed sowing and the qualified rate as response indexes.The regression models of missed sowing rate and qualified rate were established through analysis of the test data and then the parameters of garlic seed metering device were optimized based on the regression model.The platform test was carried out on the garlic seed metering device with radius,length and rotation speed of seed scoop as 16.30 mm,38.50 mm and 10.0 r/min,respectively.The results showed that the missed seeding rate was 5.50%and the qualified rate was 91.10%,which were consistent with the results predicted by the regression model.The research can provide a solid basis for precision sowing technology in garlic.