抛扬式膜际覆土马铃薯播种联合作业机设计与试验

针对传统马铃薯联合播种机播深合格率较低、膜际覆土质量差等问题,结合西北旱作区马铃薯机械化覆膜播种特点及甘肃省河西走廊马铃薯机械种植要求,设计了一种具有仿形播种能力的集旋耕、施肥、起垄、播种、覆膜和膜际覆土的马铃薯播种联合作业机。为降低地轮行走过程中对播种深度的影响,利用连杆原理分析确定了开沟器安装于仿形架的位置;为借助EDEM软件优化链勺结构参数,进行了二因素三水平的仿真试验,当链勺最大直径为77 mm,深度为25.5 mm时,取种性能较优;为提高抛扬式膜际覆土装置的覆土质量,通过土壤相对运动计算确定了覆土量;为提高抛扬叶轮的碎土性能,通过计算得叶轮半径为230 mm,起土铲后端高度为70 mm,叶轮回转角速度为4 rad/s。马铃薯联合播种机田间试验结果表明,当作业速度为0.69 m/s时,抛扬覆土式马铃薯联合播种机的合格指数为88.6%,漏种指数为5.3%,重播指数为6.1%,种植深度合格率为90.4%,种薯间距合格指数为89.4%,试验指标符合农业行业标准要求。膜际覆土倾角为65.3°,满足甘肃省河西走廊马铃薯种植覆膜要求。

Design and Test of Potato Combine Seeder with Throwing and Covering Soil on Film Edge

In the light of lower qualification rate of sowing depth and poorer quality of film edge covered with soil that the traditional potato combine seeders had, and according to characteristics of mechanized covering soil in the northwest dry farming areas and requirements of potato planting with mulching in Hexi Corridor, potato combined seeder machine with imitated terrain which had the integration of rotary tillage, sowing profiling ability of fertilizing, ridging, seeding, mulching and film edge covered soil was designed. To reduce impact on seeding depth in the process of wheel walking, using linkage principle the position of opener installed in the rack was calculated. In virtue of EDEM software parameters of chain structure were optimized with the simulation experiment of two factors and three levels, and the maximum diameter of chain was 77mm, and depth of one was 25.5mm. The amount of soil covered was calculated by relative motion to improve the quality of covering amount of soil. The height of the back end of the shovel was 70mm, and the velocity of the rotation angle of the blade was 4rad/s, the radius of the impeller was 230mm, increasing the breaking soil performance of the impeller. Test results showed that when the operation speed of overall unit was 0.69m/s, qualified index of throwing and covering soil on film edge was 88.6%, missed index was 5.3%, replay index was 6.1%, the planting depth qualified rate was 90.4%, seed spacing qualified index was 89.4%, which met the agricultural industry standard requirement. Angle between inter film soil and ground was 65.3°, which met the requirement of potato planting and mulching in the western corridor of Gansu.