大蒜直立种植机非对称式栽植器设计与试验

Design and Experiment of Asymmetrical Planting Implement for Garlic Upright Planter

针对大蒜直立种植机直立度偏低、作业效率低问题,设计了一种适用于连续式大蒜种植机非对称结构的栽植器,以抵消在栽植过程中栽植器的水平分速度不断变化对蒜种直立状态的影响。分析了栽植器和土壤对蒜种作用过程,建立了种穴底部轮廓曲线方程和大蒜直立种植装置EDEM-ADAMS仿真系统。首先根据栽植器在不同工作阶段的作用提出了上下锥角不同的两段式栽植器结构并确定了上部锥角为20°。再通过对种穴形状的对称性、种穴底部形状以及种植蒜种直立度影响的单因素仿真试验,确定了栽植器打开方式为单侧向前打开、打开时刻为栽植器运动到最低点,打开旋转中心位于栽植器下部顶点的上方110 mm、后侧15 mm。通过栽植器打开后对蒜种作用过程的模拟仿真分析,确定了栽植器的非对称结构及其相应参数。最后以蒜种直立度为指标,进行了工作参数和栽植器下部锥角的四因素三水平正交仿真试验,确定了最佳组合参数为:速比1.12、打开开度29.69 mm、打开时间0.51 s、栽植器下部锥角40.90°,此时种植蒜种直立度为72.84°。搭建了大蒜种植装置试验台对通过仿真分析设计的栽植器进行了试验验证,结果直立度为68.66°,表明建立的仿真系统正确、仿真试验结果实用可靠。

In order to solve the problems of low upright degree and low working efficiency of garlic planter,the planting implement with asymmetrical structure suitable for continuous garlic planter was designed,in order to adapt to the continuous change of the horizontal speed of planting implement during the planting process and keeping the garlic seed upright state.The action process of planting implement and soil on garlic seed was analyzed,and the equation for the contour curve at the bottom of the seed hole and the simulation system of garlic upright planting device were established.According to the role of the planting implement in different working stages,a two-stage planting implement structure with different upper and lower cone angles was proposed,and the upper cone angle was determined to be 20°.Through the single-factor simulation experiment of the influence of some factors on the symmetries of the shape of the seed-hole,the shape of bottom of the seed-hole and the upright degree of planting garlic,it was determined that the opening mode of the planting implement was one side forward opening,the opening moment was when the planting implement moved to the lowest point,and the center of rotation of the opening side was 110 mm above the apex of the bottom of planting implement and 15 mm behind the apex of bottom of the planting implement.The structure of the planting implement was optimized to be an asymmetric structure and the corresponding parameters were determined by the simulation analysis of the action process of the planting implement on the garlic seed.Four-factor and three-level orthogonal simulation experiments were carried out to study the effects of three working parameters and lower cone angle of planting implement on the upright degree of garlic seed and the optimal combination parameter was determined as the velocity ratio of 1.12,the horizontal distance of opening of 29.69 mm,the opening time of 0.51 s,the lower cone angle of the planting implement of 40.90°,and the upright degree of planted garlic of 72.84°.A test bed of garlic upright planting device was built to validate the simulation results which were verified by experiments.The test result showed that the upright degree of planted garlic was 68.66°,which indicated that the established simulation system was correct and the simulation test result was practical and reliable.