Abstract: Because pineapple is closely planted, and has thick and heavy stem and leaf, containing rich and tough fiber, the existing pineapple leaf shattering and returning field machines have to work twice to achieve shattering result. Thus, there was problems such as difficult operation, low efficiency, high energy consumption, and soil compaction, etc.. In order to solve these problems, this paper designed a twin-roller pineapple leaf shattering and returning field machine. It had 2 rollers in structure with joint-operating of improved L-shaped flail knife, straight knife and fixed knife, capable of achieving required shattering effect through beating and chopping repeatedly in one pass of field operation. Field trials showed that the pass rate ( the rate of pineapple leaf pieces with length less than 15 cm in total amount ) reached 90.8%, with a standard deviation of 0.79 and coefficient of variation of 6.22. And 89.3% of pineapple stubbles was equal to or less than the required height above soil, with a standard deviation of 1.43 and coefficient of variation of 9.76. The productivity was 0.356 hm2/h, fuel consumption was 54.14 kg/hm2, and distributing unevenness was 0.59. This machine could work  with good reliability and stability and its production index all reached design requirements and could met the actual needs of agronomy.

Key words: pineapple leaf, crushing, returning machinery, design, test analysis

摘要： 由于菠萝植株密植、茎叶厚重、叶片重叠交错且含有丰富的韧性较强的菠萝叶纤维，因此，现有的菠萝叶粉碎还田机需重复作业两遍方能达到粉碎要求，存在作业难度较大且效率低、能耗高、压实土壤等问题。针对上述问题，该文设计了一种双辊式菠萝叶粉碎还田机。该机采用双辊式作业结构，配合双L改进型甩刀和直刀与定刀联合作业，一次工作有效对菠萝茎叶完成多次击打、切割作用，一次粉碎作业满足实际农艺需求。田间试验分析表明：菠萝叶粉碎合格率（粉碎后长度小于15 cm的菠萝叶所占的比重）稳定在90.8%，标准差为0.79，变异系数为6.22；菠萝头漏出地面高度合格率稳定在89.3%，标准差为1.43，变异系数为9.76；生产效率0.356 hm2/h，油耗54.14 kg/hm2，抛洒不均匀度0.59，整机工作可靠性、稳定性及生产指标均达到设计要求，满足实际农艺需求。

关键词: 菠萝叶, 粉碎, 还田机, 设计, 试验分析