Authors

Abstract

To address the issues of incomplete threshing, separation loss, and grain breakage during the harvesting of super hybrid rice with conventional threshing and separating units in head-feed combine harvesters, a segmented-differential threshing and separating unit was developed. This unit mainly consists of a coaxial segmented-differential threshing drum and a rotary concave screen. Its structure and working principle are described in detail. A three-factor quadratic regression orthogonal rotation combination test was conducted, with the rotational speed of the segmented-differential drum, the linear velocity of the rotary concave screen, and the clamping chain speed as test factors. The grain loss rate, breakage rate, and impurity rate were taken as performance indicators. The test results were analyzed using Design-Expert 8.0.6 software to establish a mathematical model for the performance indicators and to determine the optimal combination of working parameters. Additionally, a comparative test was carried out between the segmented-differential unit and a conventional single-speed unit. The results showed that when the rotational speed of the low-speed/high-speed drum in the segmented-differential unit was 520/630 r·min-1, the linear velocity of the rotary concave screen was 1.20 m·s-1, and the clamping chain speed was 1.10 m·s-1, the grain loss rate, breakage rate, and impurity rate were 1.95%, 0.20%, and 0.56%, respectively.

Abstract in Chinese

为解决半喂入联合收割机脱粒分离装置在超级杂交稻收获过程中脱粒不全、分离损失和断粒率的矛盾，研制了半喂入联合收割机分段差动脱粒分离装置。该装置主要由同轴分段-差动脱粒滚筒和旋转凹筛组成。阐述了分段式差动脱粒分离装置的结构和工作原理。以分段差动滚筒转速、旋转凹筛线速度、夹紧链速度为试验因素，以籽粒损失率、破碎率、杂质率为性能指标，进行三因素二次回归正交旋转组合设计试验。本文利用Design-Expert8.0.6软件对试验结果进行分析，建立脱粒分离装置性能指标数学模型，确定最佳工作参数组合。此外，本文还对分段脱粒分离装置与常规单速脱粒分离装置进行了对比试验。结果表明:当分段装置低速/高速滚筒转速为520/630 r•min-1，转凹筛线速度为1.20 m•s-1，夹紧链速度为1.10 m•s-1时，籽粒损失率、破碎率和杂质率分别为1.95%、0.20%和0.56%。