玉米收获机多棱立辊式摘穗装置设计与试验

Design and Experiment of Corn Harvester Polygonal Vertical-rollers Snapping Means

摘要:

针对现有玉米收获机摘穗装置存在籽粒啃伤、啃落导致损失严重等问题，设计了一种结构简单、摘穗效果好、可靠性高的多棱立辊式摘穗装置。研究了立式激振折断的摘穗机理，分析了多棱立辊式摘穗装置主要结构参数的设计方法；通过正交试验确定了影响摘穗质量的主次因素为棱边数、摘穗辊转速和摘穗辊直径；较优组合为：摘穗辊直径为7cm、棱边数为8、摘穗辊转速为950r/min，在该条件下本摘穗辊的籽粒破损率为0.13%、落地籽粒损失率为0.28%、茎秆折断率为0.53%，满足国家标准要求。在较优组合条件下进行了调整内角Δ大小的验证试验，通过试验可知调整内角Δ为16°时，即最大调整范围的一半时摘穗质量最好。

Abstract:

The grain bite wounds and grain bite off of corn harvester snapping means caused a serious loss. Aiming at those existed problems, a polygonal vertical-rollers snapping means with simple structure, good snapping effect and high reliability was designed. The mechanism of the vertical vibration snapping broken was studied. And then the design methods of main structural parameters for polygonal vertical-rollers snapping means were analyzed. Orthogonal design method was used for test design with influence factors of the number of edges, snapping roll speed and snapping roll diameter. By orthogonal test, it can be known that the factors affecting the quality of snapping in order of their importance were the number of edges, snapping roll speed and snapping roll diameter. By orthogonal test, it can be known that the optimum combination was snapping roll diameter of 7cm, the number of edges of 8, snapping roll speed of 950r/min. Test under optimum combinations was carried out, and it was found that the grain broken rate was 0.13%, the grain loss rate was 0.28%, and the rate of broken stem was 0.53%. The grain losses and damages were both far lower than the national standard. Under optimum conditions, validation tests were done to determine the most appropriate size of the interior angle adjustment. The test result showed that the resizing interior angle Δ was 16°, which was half of the maximum interior angle range of adjustment, and under this conditions the harvesting quality was the best.