秸秆捡拾粉碎掩埋复式还田机设计与试验

针对黄淮海地区存在玉米秸秆量大、后续播种难度大等问题,设计了一种秸秆捡拾粉碎掩埋复式还田机,能一次完成秸秆捡拾、粉碎、输送和开沟掩埋等作业。应用典型弹齿滚筒式捡拾装置工作原理,通过弹齿捡拾秸秆过程的分析,确定了弹齿滚筒式捡拾装置的导轨中心线轨迹和捡拾相位,并对弹齿进行了基于实际作业情况的运动学分析,其运动轨迹与速度变化规律能够满足捡拾秸秆的需求。采用动定刀支撑切割方式粉碎秸秆,并利用粉碎腔体内的高速气流和置于腔体后侧的挡草板,实现秸秆掩埋还田比例调节和部分秸秆抛撒还田。开沟装置、秸秆输送导向装置出草口和圆盘覆土装置从前向后依次布置,顺序完成开沟、秸秆入沟和覆土掩埋工序。田间试验表明,当作业速度为3 km/h时,秸秆捡拾率为93.5%,粉碎长度合格率为92.6%,开沟深度稳定性系数为95.0%,秸秆入沟率与预先设定的掩埋比例基本一致,各项技术指标满足技术要求。

Design and Experiment on Straw Pickup-chopping and Ditch-burying Integrated Machine

In Huang-Huai-Hai area, the large amount of maize straw cover resulted in increasing difficulties in winter wheat sowing, and an integrated machine was developed to pick up, crush and bury the corn straw at single operation to cope with this problem. The trace and phase position of the guideway centerline of spring-finger cylinder pickup device were determined based on the working principle and working process analysis of the typical spring-finger cylinder pickup device. A kinematic analysis on spring-finger was carried out under practical condition, and changes in both movement trajectory and speed were able to meet the requirements. Straw was chopped with a fixed knife and a high-speed rotating knife, while the high-speed air flow within the crushing chamber that formed by the rotation of the chopping roller, as well as the baffle plates placed in the back of the crushing chamber, were used to adjust the proportion of the straw to be buried and scatter the partial straw from the places without baffle plates to the surface of ground. Ditching device, the outlet of straw guided-conveying device and the disc covering device were arranged from front to back, so as to sequentially complete ditching, straw-disposing and soil-covering. As indicated in the field experiment, the straw picking up rate was 93.5%, the qualification rate of straw chopping length was 92.6%, the trench depth stability ratio was 95.0% when at a operation speed of 3km/h, the proportion of straw that had been buried into the ditch was in accordance with the pre-set proportion, which showed that the proportion of the buried straw can be adjusted successfully through different widths of the baffle plates. As a consequence, all the technical indicators of this machine succeeded in meeting the technical requirements.