柔性差速带式单株大豆脱粒装置设计与试验

Design and Experiment on Single-plant Soybean Threshing Device with Differential Speed Flexible Belts

针对育种单株大豆脱粒过程中的大豆籽粒混杂和机械损伤等问题,设计了一种柔性差速带式单株大豆脱粒机的脱粒装置。为寻求脱粒装置的结构与工作参数对其性能的影响规律和最优参数组合,采用4因素5水平二次回归正交旋转中心组合试验方法,以脱粒间隙、上下带速度差、下带速度和脱粒行程为影响因素,以大豆籽粒的未脱净率、夹带损失率、破碎率和平均生产率为评价指标,对其进行优化试验研究。结果表明:对于籽粒含水率16%~18%的收获期大豆种子,当脱粒间隙7.55~13.00 mm、上下带速度差0.59~0.70 m/s、下带速度0.84 m/s、脱粒行程660 mm时,脱粒装置的未脱净率低于1.2%、夹带损失率低于0.9%、破碎率低于0.8%、平均生产率高于35 kg/h。

In order to solve the problems of soybean grain mixing and mechanical damage caused by single threshing process of soybean. A threshing device was designed for single-plant thresher with differential speed flexible belts. Single threshing was an important part of breeding experiments because it can avoid mixed seeds when there was smaller breeding area,small sample size and precious varieties.Meanwhile,most of the existing threshing devices were roller-type and made by rigid materials,which could cause mechanical damage to the soybean grains easily. However,the new soybean threshing device solved the problem of mechanical damage which would affect the germination and emergence of soybean seeds. And in order to find the optimal combination of the structure and working parameters of the differential flexible belt type soybean thresher, the method of four-factor with five-level quadratic regression orthogonal rotation center combination was employed. The factor of cylinder clearance,top and low section velocity difference,low section velocity,threshing trip were discussed. And the loss of unthreshed grain, loss of entrap grain, cracked grains and average productivity were selected as evaluating indexes. The results showed that the rank of the effect of four factors on loss of unthreshed grain from high to low was as follows： top and low section velocity difference,the cylinder clearance,low section velocity and threshing trip; on loss of entrap grain： low section velocity,the cylinder clearance,threshing trip,top and low section velocity difference; on cracked grains： the cylinder clearance,top and low section velocity difference,threshing trip and low section velocity; on average productivity： threshing trip,low section velocity difference,the cylinder clearance,top and low section velocity difference. In the case of soybean grain with 16% - 18% moisture content,the optimum combination region of the cylinder clearance was 7. 55 - 13. 00 mm,the top and low section velocity difference was 0. 59 - 0. 70 m/s,the low section velocity difference was 0. 84 m/s,the threshing trip was 660 mm; under this condition,loss of unthreshed grain was less than 1. 2%,loss of entrap grain was less than 0. 9%,cracked grains were less than 0. 8%,average productivity was more than 35 kg/h. The results laid a theoretical foundation for the development of single-plant thresher with differential speed flexible belts.