自解捆式果园秸秆覆盖机设计与试验

Design and Test of Self-unbaling Orchard Straw Mulching Machine

针对果园秸秆覆盖机不适应捆状秸秆、装载量小以及覆土装置易被碎石卡死问题,设计了一种自解捆式果园秸秆覆盖机。该机型由履带底盘、料箱、解捆铺料装置和覆土装置等组成。解捆铺料装置为齿带式结构,安装于料箱后部。为适应多种秸秆捆尺寸,提高抓料解捆能力和铺料均匀性,通过对解捆铺料过程分析确定了解捆铺料装置高度、倾角和齿带转速等关键参数范围;为了实现切绳和破捆过程滑切减阻,设计了三角形拨料刀齿,并基于刀齿对秸秆的扰动区域分析,对刀齿排布进行了设计;设计了一种双向对抛式覆土装置,同步对秸秆层进行薄土盖压。试验结果表明:覆盖机的秸秆装载量提高到原来的3.1倍;当覆盖机车速在0.8~1.4 km/h,解捆铺料装置齿带转速在180~240 r/min时,秸秆覆盖层厚度为5.1~18.1 cm(标准差小于等于3.4 cm),薄土盖压层厚度为2.3~4.0 cm,无卡死现象,满足作业要求;建立的秸秆覆盖厚度模型决定系数为0.9672。该机实现了秸秆解捆、行间覆盖与薄土盖压一体化作业。

Aiming at solving the problems,such as inadaptation to baled straw,insufficient loading capacity,and easily blocked soil covering device,that happened in the first generation orchard straw mulching machine,a self-unbaling orchard straw mulching machine was developed.The machine consisted of tracked chassis,unbaling-spreading device,bin and soil covering device,etc.The unbaling-spreading device was a toothed belt structure and installed at the rear of the bin.To adapt to a variety of straw bales and improve bale breaking ability and mulch uniformity,after analyzing the process of unbaling and spreading,the key parameters such as inclination angle,height and rotating speed of the device were determined.To reduce drag during rope cutting and bale breaking,a triangular knife-tooth was designed,and the distribution of the knife-teeth was planned based on the analysis of straw compression and disturbance area.A double-sided opposite-throwing soil covering device was designed to cover soil on the surface of straw layer synchronously.The test results showed that the straw loading capacity was increased to 3.1 times of the original machine.When the speed of the straw mulching machine was 0.8~1.4 km/h and the rotating speed of the unbaling-spreading device was 180~240 r/min,the thickness of the straw mulching layer was 5.1~18.1 cm with standard deviation not more than 3.4 cm,and the thickness of the soil covering layer was 2.3~4.0 cm with no interruption happened during soil-covering,meeting the requirements for straw mulching in orchard.The established straw mulch thickness model,with a determination coefficient of 0.9672,can be used to guide the parameters adjustment in actual production.The machine realized the operation integration of straw unbaling,inter-row mulching and thin soil covering,which laid foundation for improvement of orchard straw mulching mechanization technology and equipment performance.