行星轮式大蒜插播机播种直立度优化与试验

大蒜机械化播种的植入环节中,在蒜种-土壤-触土部件强耦合作用下,正头后的蒜种直立度极易变低,如何“保姿植入”成为亟待解决的关键技术。针对此问题,该文以行星轮式大蒜插播机为研究对象,对插播鸭嘴的尖部运动轨迹进行分析,明晰了影响植后蒜种直立度的关键因素为插播鸭嘴的线速度、开启相位角及插播鸭嘴张开角度与凸轮凸起段对应的圆心角之比(开口速比)。运用Box-Benhnken中心组合试验方法对插播鸭嘴的线速度、开启相位角、开口速比进行三因素三水平二次回归试验设计,进行了插播试验,采用Design-expert软件建立响应面数学模型,对影响直立度的关键参数进行了综合优化,求解出最优工作参数组合为插播鸭嘴的线速度200 mm/s,开启相位角20°,开口速比2。大田试验结果表明,最优参数作业的蒜种直立度均值为63.2°,较优化前提高了21.8%,满足大蒜种植的蒜种直立度要求。

Optimization and experiment of planting perpendicularity of planetary wheel garlic planter

In the implantation process of garlic mechanized seeding, under the strong coupling among garlic seeds, soil and parts touching it, the verticality of adjusted garlic seeds is very easy to reduce again, thus affecting the final garlic output and garlic quality. How to ensure that garlic seeds are planted in an upward vertical direction has become a key technology to be solved. To solve this problem, this paper took the planetary wheel garlic planter designed in the early stage as the research object, introduced its structure and working principle in combination with the whole garlic planter, realized the adjustment of the opening and speed ratio of the inserting duckbill by processing the cams of different planters, and changed the opening phase angle of the inserting duckbill by adjusting the circumferential position of the cams installed in the machine. Based on the establishment of garlic inserting seed model and the analysis of the process, the tip motion equation of the duckbill was established and imported into CAXA software to generate the movement track. Through the analysis of the movement track under different parameters, it is clear that the key factors that affect the verticality of garlic seeds after planting are the linear speed of the inserting duckbill, the opening phase angle and the ratio of the opening angle of spigot duck''s beak to the center angle corresponding to the cam convex section (the opening and speed ratio). In order to verify the correctness of the theoretical analysis, a garlic planting test-bed was developed, and the indoor experiment of Cangshan garlic planting was carried out. Through the single factor experiment, it was determined that the value range of the linear speed of the duckbill was 200-500 mm/s, the range of the opening phase angle was 0-20°, and the range of the opening and speed ratio was 1-2. In order to obtain the optimal parameters of these three factors, the Box-Benhnken central composite test method was used to design the linear velocity, opening phase angle and opening velocity ratio of the spilt duck''s beak by three factors and three levels quadratic regression test. The sowing test was carried out, and the response surface mathematical model was established by using Design-expert software. The key parameters affecting the verticality were comprehensively optimized. The optimal working parameters are as follows, the linear speed is 200 mm/s, the opening phase angle is 20°, the opening and speed ratio is 2. In order to verify the performance of the inserter using the optimized parameters, field experiments were carried out. The results showed that the average vertical degree of garlic seeds in the optimal parameter operation was 63.2°, which was 21.8% higher than that before. It not only met the requirements of garlic planting vertical degree, but also further improved the integration of agricultural machinery and agronomy, which improved the guarantee for large-scale mechanized vertical sowing of garlic.