驱动式马铃薯中耕机关键部件设计与碎土效果试验

Design of Key Components of Driving-type Potato Cultivator and Its Soil-broken Effect Experiment

针对传统锄铲式中耕机在粘重土壤作业中碎土率低、碎土后土壤粒径较大等问题,对驱动式马铃薯中耕机的关键部件进行了设计,通过对整体结构和工作原理的阐述,对由碎土刀与刀盘组成的耕作部件进行参数设计与运动学分析,并对碎土刀切削土壤过程的剪切应力进行理论分析,运用Matlab确定了影响剪切应力的因素参数范围。以碎土刀刀轴转速、前进速度、耕深、碎土刀折弯角和刃口长度为因素,以碎土率为指标进行了试验台试验,并进行了正交回归方差分析。试验结果表明:在刀轴转速为275 r/min、前进速度为0.75 m/s、耕深为0.18 m、碎土刀折弯角为150°、刃口长度为0.07 m时,耕作后土壤碎土率为93.8%。试验确定了碎土刀的最优结构参数,所设计的碎土刀能增强碎土效果,关键部件的设计满足马铃薯中耕作业耕深、碎土要求。该研究基本解决了中耕过程中碎土率低、碎土后土壤粒径较大等问题,作业效果更加明显,为马铃薯中耕机的设计改进与优化提供了理论支撑和技术参考。

The traditional plough share-type cultivator shows characteristics that the soil particle size is larger after broken, the working parts can easily wrapped and has lower soil-broken rate during operation in heavy soil. And ridge distance of cultivator is not applicable for potato. The key component of driving- type potato cultivator was designed, and the structural parameters that affected the effect of soil-broken were concluded. The structure and working principle of the cultivator were illustrated, and the rotating monomer that made of soil-broken knife was theoretically analyzed. The factors that affected soil-broken rate were got. Regarding the folding corner and blade length of the soil-broken knife, knife-cylinder, forward speed and tillage depth as the experimental factors, regarding soil-broken rate as the experiment indicators. The test was taken in the College of Engineering, Northeast Agricultural University at the beginning of November, 2016, which was carried out in the room. The power was provided by generator and the tillage depth can be adjusted by actuating device. Experimental results showed that the machine had the soil-broken rate of 93.8% , when the knife-cylinder was 275 r/min, the speed was 0.75 m/s, blade folding corner was 150°, the length of the blade was 0.07 m, and tillage depth was 0. 18 m. The optimal structural parameters of soil-broken knife were determined by experiment. And the experiment also verified the accuracy of theoretical formula. It was well conformed to the agronomic requirements of cultivator. The structure of soil-broken knife assembled on driving-type cultivator can enhance the cutting force to achieve better soil crushing effect. The machine basically solved the serious problems such as the lower efficiency of soil broken. It was more suitable for the tillage operation of potato when compared with the traditional cultivator. The study provided important theoretical and technical reference for the improvement and optimization of the driving-type potato cultivator.