自走式制种玉米联合收获机设计与试验

Design and Experiment of Self-propelled Seed Corn Combine Harvester

大田玉米收获机收获制种玉米时容易产生伤穗落籽、杂物堵塞等现象,本文针对适收期制种玉米生物特性,设计了一种大型制种玉米联合收获机,采用小行距对行柔性板式摘穗割台和可替换组合式剥皮装置,确保低损摘穗、输送、剥皮作业,降低籽粒损失与损伤;其中割台上方配备钢质覆胶弧形摘穗板,“橡胶+钢质”夹持输送链和六棱低速拉茎辊,可替换组合式剥皮装置采用柔性破皮+揉搓+降速组合形式。通过Plackett-Burman试验设计筛选提取影响机具指标的主要因素,采用Box-Behnken试验设计原理,以机具前进速度、拉茎辊转速和剥皮辊转速为试验因素,以总损失率与含杂率为性能指标,通过田间试验对机具进行检验,优化得出机具最佳作业参数。试验结果表明,优化后,当机具前进速度为4.87 km/h、拉茎辊转速为877.27 r/min、剥皮辊转速为442.52 r/min时,果穗总损失率为1.61%,含杂率为0.55%。田间试验结果表明,当收获机前进速度为4.9 km/h、拉茎辊转速为880 r/min、剥皮辊转速为450 r/min时,果穗总损失率为1.64%,含杂率为0.57%,满足制种玉米机械化联合收获的作业要求,可为制种玉米联合收获机设计与试验提供参考。

Aiming at the field corn harvester harvesting seed corn is prone to the phenomenon of injury to ears and seeds,debris blockage,etc.,a large-scale seed corn combine harvester for the biological characteristics of seed corn in the suitable harvest period was designed.The machine adopted small row spacing to row flexible plate picking cutting platform and replaceable combined peeling device,to ensure low-loss picking,conveying,peeling operation and reduce seed loss and damage,which was equipped with steel rubber-covered curved picking plate on the upper part of the cutting platform,“rubber+steel”clamping conveyor chain and six-pronged low-speed pulling rollers,and the replaceable combined peeling device adopted flexible peeling+rubbing+speed reduction.The main factors affecting the machine indexes were extracted by screening through the Plackett Burman experimental design,and the Box Behnken experimental design principle was applied,taking the forward speed of the machine,the rotational speed of the stem pulling roller and the rotational speed of the peeling roller as the experimental factors,and taking the total loss rate and the impurity rate as the experimental indexes,the machine was examined through the field test,and the best operating parameters of the machine were optimized.The test results showed that the total loss rate of cob was 1.61%and the impurity rate was 0.55%when the optimized machine forward speed was 4.87 km/h,the stem pulling roller speed was 877.27 r/min and the peeling roller speed was 442.52 r/min.It was verified in the field test:when the forward speed of the harvester was 4.9 km/h,the rotational speed of the stalk pulling roller was 880 r/min,and the rotational speed of the peeling roller was 450 r/min,the total loss rate of the cob was 1.64%,and the rate of impurity was 0.57%,which met the requirements of the mechanized joint harvesting of corn for seed production,and it can be used as a reference for the design and test of the joint harvesting machine for corn for seed production.