【摘要】 秸秆还田作为农作物秸秆的有效利用方式之一,能培肥地力,蓄水保墒。为了改善东北地区耕层变浅、犁底层上移、玉米秸秆产量大、后续处理困难等问题,设计了一种秸秆直注深埋还田机。该机由秸秆粉碎装置,输送装置、开沟装置和覆土装置组成,能一次性完成秸秆捡拾、输送和深埋等作业内容,可将地表秸秆埋至地下300mm土层中,满足打破犁底层,构建合理耕层,提高秸秆利用率的要求。该机输送装置中部安装卸料室,实现秸秆从两侧向中间聚拢并向下运动的效果。通过对输送装置分析得知,螺旋叶片设计直径315mm,螺距315mm,当螺旋轴转速为350～450r·min-1时,卸料效果良好。参考双翼铧式开沟器作业后的土壤截面设计了柳叶形直注铲,该铲底端秸秆出口设计成流线型柳叶状,铲横截面形状为椭圆形。通过分析计算得出直注铲设计高400mm、铲宽320mm、圆心角θ=60°时,铲横截面积为9.92×104mm2,满足卸料要求,同时能达到开沟破土并回填部分土壤的作业效果。以拖拉机前进速度、秸秆覆盖量和输送装置转速为因素,以秸秆还田率为指标,设计了正交试验。结果表明:拖拉机前进速度和输送装置转速对还田率影响显著,当前进速度为5km·h-1,输送装置转速为450r·min-1时,还田率为90.5%。该试验结果表明了机具作业性能符合设计要求,卸料室和直注铲的设计为秸秆还田机输送装置和开沟装置的优化设计提供理论和实践参考。更多还原

【Abstract】 As one of the effective utilization way s o f crop straw, straw returning can improve soil fertility, water storage and moisture conservation. In order to improve the problems of shallow plough layer, uplift of plough bottom, high yield of corn straw and difficulty of follow-up treatment in Northeast China, a direct injection straw deep bury and returning machine was designed.The machine was composed of straw crushing device, conveying device, ditching device and covering device. It could complete straw collection, transportation, and deep burying at one time. And bury straw into the 300 mm underground soil layer, which meets the requirements of breaking the plough bottom, constructing a reasonable tillage layer and improving the utilization rate of straw. The discharging mechanismwas installed in the middle of the conveying device to realize the effect that the straw gathered from both sides of the auger and moved down. Through the analysis of the conveying device: the design diameter of the helical blade was 315 mm and the pitch was 315 mm. When the speed of the helical shaft was 350-450 r·min-1, the discharge effect was fine. Using the soil cross section after the operation of double-winged furrow ditching, a willow-shaped direct injection shovel was designed. The straw outlet at the bottom of the shovel was designed as a streamlined willow-shaped, and the crosssection was elliptical. Through analysis and calculation, it is concluded that when the design height of the shovel was 400 mm,the width was 320 mm and the center angle was equal to 60°, the cross-sectional was 9.92 ×104 mm2, which meets the requirement of discharging, and achieves the operation effect of ditching and backfillingpart of the soil. We designed the orthogonal test with the speed of tractor, straw cover amount and conveying device rotational velocityas the experimental factors to test the buried rate. The results showed that when the tractor’s speed was 5 km·h-1, the conveying device rotational velocity was450 r·min-1, the buried rate was 90.5%. The test results showed that the working performance of the machine met the design requirements, and the design of discharging mechanism and shovel provided theoretical and practical reference for optimum design of conveying device and ditching device of straw returning machine.更多还原