Authors

Abstract

Aiming at the problems of large loss rate and high damage rate during buckwheat threshing, an inner and outer roller buckwheat thresher was designed. The device is mainly composed of an inner roller and an outer roller, the inner roller is a rod-tooth combination roller, and the outer roller is a grid roller, the inner and outer rollers can be rotated independently. The outer roller is supported on the friction wheels and the supporting wheels, and driven to rotate by the friction wheel transmission system. The compression device is installed at the top to prevent the outer roller from slipping during the rotation. During working, the materials enter between the inner and outer rollers and the separation of grains and stems under the brushing and kneading action of the inner and outer rollers takes place. In order to push the materials between the inner and outer rollers smoothly, a double spiral blade type screw feeding device was designed. By establishing a mathematical model of material pushing, the screw feeding device has a material conveying speed of 1.87 m/s and a conveying capacity of 4.29 kg/s. In order to study the threshing performance, the threshing device was installed on the basis of the Kubota 688 tracked type combine to complete a prototype of a tracked buckwheat combination harvester. Field tests show that the grain impurity rate is 6.50%, the grain damage rate is 1.42%, the threshing loss rate is 0.25%, the cleaning loss rate is 1.01%, the direct loss rate of the header is 2.43%, and the total machine harvest loss rate is 3.69% at the working speed of 0.53 m/s and the feeding rate of 0.41 kg/s. The test results provide a basis for the improvement of buckwheat mechanized harvesting machinery.

Abstract in Chinese

针对荞麦脱粒损失率大、破碎率高等问题，设计了内外滚筒式荞麦脱粒机，该装置主要由内滚筒和外滚筒组成，内滚筒为纹杆—钉齿组合式滚筒，外滚筒为栅格滚筒，内外滚筒均可独立旋转。工作时，物料进入内外滚筒间，在内外滚筒的梳刷、揉搓作用下完成籽粒与茎秆的分离。为了将物料顺利推送至内外滚筒之间，设计了双螺旋叶片式螺旋喂入装置，并通过建立物料推送的数学模型，得到螺旋喂入装置物料输送速度为1874mm/s，输送量为4.29kg/s。为了对该脱粒装置脱粒性能进行研究，在久保田688型履带式联合收获机基础上，安装该脱粒装置，完成履带式荞麦联合收获机样机。通过田间试验得到：该样机在作业速度为0.53m/s，喂入量为0.41kg/s的条件下，籽粒含杂率为6.50%，籽粒破碎率为1.42%，脱粒损失率为0.25%，清选损失率为1.01%，割台直接损失率为2.43%，总损失率为3.69%，试验测试效果良好，为荞麦机械化收获机械的改进提供依据。