Authors

Abstract

To address the issues of high kernel breakage rate and poor flexibility adaptation in threshing devices for direct corn kernel harvesting, this study proposes a flexible threshing device based on a single-point hinged structure. In this design, the threshing elements are flexibly mounted via single-point hinges, allowing them to rotate upon impacting corn kernels. This rotational motion provides an impact-buffering effect during the threshing process, thereby reducing the risk of kernel breakage.By comparing the dynamic characteristics of the single-point hinged flexible structure with those of a rigid structure, the superiority of the proposed device is confirmed. A contact force model is established to analyze key parameters influencing threshing performance, identifying the mass of the threshing element, rotational speed, and structural configuration as the primary influencing factors. A coupled simulation model was developed using RecurDyn and EDEM software to investigate the effects of threshing element mass, rotational speed, and structural configuration on the kernel breakage rate and unthreshed rate of the device, and to determine the optimal parameter range. Based on a three-factor, three-level orthogonal experimental design, the optimal working parameters of the device were identified as follows: threshing element mass of 200 g, rotational speed of 600 r/min, and a composite structural configuration. Under these conditions, the kernel breakage rate was 3.95% and the unthreshed rate was 0.88%, meeting the practical requirements for harvesting performance. This study provides theoretical support and a technical pathway for the design of high-efficiency, low-damage threshing devices for direct corn kernel harvesting.

Abstract in Chinese

为解决玉米籽粒直收中脱粒装置对籽粒破碎率高、柔性适应性差等问题，本文提出了一种基于单点铰接结构的玉米柔性脱粒装置。该装置通过将脱粒元件以单点铰接的形式柔性安装，让脱粒元件在冲击玉米籽粒的同时可以回转，旋转脱粒过程具有缓冲冲击能力，以降低籽粒破碎风险。通过将单点铰接柔性结构与刚性结构脱粒时的动力学特性进行对比，确定该装置的优越性。建立接触力模型并分析影响脱粒效果的关键参数，确定了脱粒元件质量、转速和结构形式作为主要影响因素。基于 RecurDyn 和 EDEM 软件构建了耦合仿真模型，探究了该装置中脱粒元件的质量、转速以及结构形式对籽粒破碎率和未脱净率的影响规律，并确定了较优参数区间。通过三因素三水平正交试验，确定了该装置的最佳工作参数为：脱粒元件质量为 200g、转速为 600 r/min、结构形式为组合型，此时籽粒破碎率为 3.95%，未脱净率为 0.88%，作业性能满足了实际收获需求。本研究为高效、低损伤的玉米籽粒直收脱粒装置设计提供了理论支持和技术路径。