纵轴流玉米脱粒分离装置喂入量与滚筒转速试验

Experiment on Feed Rate and Cylinder Speed of Longitudinal Axial Flow Threshing and Separating Device for Maize

在玉米籽粒直收过程中,脱粒滚筒转速与联合收获机的额定喂入量相匹配才能发挥出最佳的作业效果。为了获得不同喂入量时玉米联合收获机最优的滚筒转速范围,设计了一种零部件可更换、结构参数和工作参数均可调的纵轴流玉米脱粒分离装置,并在自主研制的试验台上以脱粒滚筒转速、喂入量为影响因素,以籽粒破碎率、未脱净率为性能指标进行玉米脱粒试验。通过台架试验、回归分析和单变量求解,最终确定了不同喂入量的最优滚筒转速范围:喂入量为8 kg/s时,最优的滚筒转速为254~486 r/min;喂入量为10 kg/s时,最优的滚筒转速为278~466 r/min;喂入量为12 kg/s时,最优的滚筒转速为313~445 r/min。在以上条件下籽粒破碎率均小于5%,未脱净率小于2%,达到了国家和相关标准的要求。

In the process of maize grain direct harvest,the threshing cylinder speed should be matched with the feed rate of combine harvester,so that the best effect of the operation can be achieved. In order to obtain the optimal ranges of the threshing cylinder speed of maize combine harvester at different feed rates,a longitudinal axial flow maize threshing and separating device was designed and developed,whose components and parts can be changed easily. It was also convenient to adjust the structure parameters and working parameters. The threshing cylinder speed and the feed rate were selected as the influence factors,and the maize kernel damaged rate and un-threshed rate were selected as the performance indexes in the experiments. The test results showed that with the increase of threshing cylinder speed,the maize kernel damaged rate was increased and the un-threshed rate was decreased. At the same threshing cylinder speed,with the increase of the feed rate,the maize kernel damaged rate and the un-threshed rate were increased slightly. Through the bench tests,regression analysis and single variable solution,the optimal ranges of the cylinder speed at different feed rates of the threshing and separating device were determined. The optimal range of cylinder speed was 254 ~ 486 r/min at the feed rate of 8 kg/s. The optimal range of cylinder speed was 278 ~ 466 r/min at the feed rate of 10 kg/s. The optimal range of cylinder speed was 313 ~ 445 r/min at the feed rate of 12 kg/s. Under all the conditions above,the maize kernel damaged rate was less than 5%,and the un-threshed rate was less than 2%,which reached the requirements of the national standards. The research result of the threshing and separating device provided reference for design of maize grain harvester,and the research on adaptive model of the feed rate and threshing cylinder speed.