Abstract: In order to solve the problem that the standard forage grass length rate can not meet the national standard due to the ramie fiber winding the chopping system and the uneven feeding length, a chopping system of forage ramie harvester with adaptive feeding gap was designed, which was composed of feeding press roll parts and chopping parts. The feeding press roll parts of the chopping system adopted floating press roll to realize the self-adaptive adjustment of feeding gap with the change of feeding amount. The forage ramie was chopped by a high-speed flat hob chopper (moving knife) under the clamping and pushing action of the feeding press roll parts. The main influencing factors of standard grass length rate were the rotate speed of feeding press roll, the rotate speed of chopper and the gap between moving knife and stationary knife. The performance test-bed of the chopping system was designed, and the orthogonal combination test of multiple factor quadratic rotation was carried out. The experimental results showed that the optimal combination of working parameters of chopping system was the rotate speed of feeding press roll 159.16 r·min-1, the rotate speed of chopper 848.11 r·min-1, the gap between moving knife and stationary knife 0.65 mm. The standard grass length rates of the optimized model and validation test were 93.18% and 92.96%, respectively, and the relative deviation between them was 0.24%, which met the requirements of forage ramie harvester.

Key words: ramie for feeding, harvester, chopping system, design

摘要： 为解决饲用苎麻收获机工作中纤维缠绕切碎系统以及喂料不均匀导致标准草长率达不到国家标准的问题，设计了一种喂料间隙自适应的饲用苎麻收获机切碎系统，由喂入压辊部件和切碎部件组成。该切碎系统的喂入压辊部件采用浮动压辊实现喂料间隙随喂入量变化自适应调节，饲用苎麻在喂入压辊部件的夹持推送作用下，由高速旋转的平板型滚刀式切碎器（动刀）切碎。分析得到了影响标准草长率的主要因素有喂入压辊转速、切碎器转速、动定刀间隙。试制了切碎系统性能考核试验台并进行了多因素二次旋转正交组合试验。结果表明，切碎系统的最优工作参数组合为喂入压辊转速 159.16 r·min-1、切碎器转速 848.11 r·min-1、动定刀间隙 0.65 mm。优化模型与验证试验所得的标准草长率分别为 93.18%、92.96%，二者的相对偏差为 0.24%，满足饲用苎麻收获机作业要求。

关键词: 饲用苎麻, 收获机, 切碎系统, 设计