紫云英绿肥盛花期埋切翻压组合作业机设计与试验

为实现紫云英绿肥规模化种植区域的绿肥高效、低耗机械化翻压,基于前端埋切、后端翻压的结构配置思路,设计了一种无动力输入的紫云英绿肥盛花期埋切翻压组合作业机。对盛花期紫云英生物学特征及压切特性开展研究,进而设计了辊筒组件、前悬挂连接组件、栅条式翻转犁等主要工作部件;通过理论计算和力学分析,得到实现紫云英茎秆顺畅埋切的压切辊半径为305 mm、压切刀滑切角范围为34. 3°～55. 7°;采用水平直元线法设计了栅条式犁体曲面,推导得到导曲线抛物线方程,并绘制了犁体直元线角变化规律图。紫云英绿肥盛花期田间翻压试验结果表明:在机具作业速度为5. 8～6. 0 km/h条件下,茎秆切断长度合格率92%,耕宽稳定性变异系数3. 7%,耕深稳定性变异系数5. 6%,土垡破碎率85. 6%,植被翻压覆盖率98. 3%,试验指标均符合国家和行业标准要求。设计的埋切翻压组合作业机工作效率可达0. 67～1. 20 hm2/h,在翻压质量和组配方式上明显优于目前我国常用的畜力犁、铧式犁、旋耕机等翻压方式,具有很好的推广应用价值。

Design and Experiment of Incisal-burying and Ploughing Combined Machine for Astragalus smicus Green Manure in Full-bloom Stage

In order to realize high-efficiency and low energy-consumption mechanized ploughing operation in the large-scale planting area of Astragalus smicus green manure, based on the structure placement idea of front-end buried-cutting and back-end overturning, an incisal-burying and ploughing combined machine with no power input for Astragalus smicus green manure in its flourishing period was designed. The biological characteristics and pressure-shear strength test of Astragalus smicus in full-bloom stage were studied, and then the key components such as roller components, front suspension connection components and grid-type plough were designed. Through theoretical calculation and mechanical analysis, the radius of press-cutting roller for smooth incisal-burying of Astragalus smicus stalks was 305mm, and the sliding cutting angle was ranged from 34.3° to 55.7°, the grid-type plough surface was designed by using the horizontal straight element method, the parabolic equation of the guide curve was derived and the influence regularity of plough element-line angle was drawn as well. The results of field overturning test of Astragalus smicus green manure in full-bloom stage showed that with the operation speed of 5.8~6.0km/h, the qualified rate of stem-cutting length was 92%, the stability variation coefficient of tillage width was 3.7%, the stability variation coefficient of tillage depth was 5.6%, the rate of soil fragmentation was 85.6%, and the rate of vegetation overturning coverage was 98.3%, the test indexes met the requirements of national and industrial standards. The designed incisal-burying and ploughing combined machine can work efficiently up to 0.67~1.20hm2/h, which was obviously superior to the conventional overturning modes such as animal plough, mouldboard plough and rotary tiller in terms of overturning quality and the combination pattern, and had good popularization and application value.