履带式全喂入水稻联合收获机振动测试与分析

针对国产履带式全喂入水稻联合收获机整机振动大、无故障工作时间短、可靠性差等问题,以沃得巨龙280型联合收获机为研究对象,在发动机空载、整机空载和田间收获等5种工况下,采用DH5902动态信号分析系统对整机多点振动情况进行了测试与分析,得到了8个测点的时域特性和频谱特性的分布规律。试验结果表明:发动机的上下振动、振动筛的前后运动和切割器的左右运动是形成水稻联合收获机整机振动的主要原因,而输送槽、风机和脱粒滚筒等部件的回转运动为次要原因。整机全油门空载工况下发动机引起的振动频率为71.78 Hz,振动筛、切割器、风机、脱粒滚筒I和脱粒滚筒II引起的激振频率分别为6.35、8.79、19.04、12.70和23.44 Hz,驾驶座椅的减振结构需进一步优化。研究结果为改善履带式全喂入水稻联合收获机的驾驶舒适性,提高其工作可靠性提供参考。

Vibration measurement and analysis of tracked-whole feeding rice combine harvester

In order to solve the problems of violent vibration, short time between failures and poor reliability existing in the crawler-type rice combine in China, experiments were conducted to analyze the characteristic of vibration source on combine World Dragon 280. 8 measuring points of engine support, cutter drive shaft support, vibrating sieve drive shaft support, drum support I, drum support II, chute driving wheel support, fan shaft support, and seat support were marked on the combine. Time-domain signals and frequency spectral characteristics of 8 measuring points were measured and analyzed by 5902 dynamic signal analytical systems in 5 different conditions such as no-load mode of engine, no-load mode of the whole machine and field harvesting. The result shows that up-and-down vibration of the engine, before-and-after vibration of the vibrating screen and left-and-right vibration of the sickle are the main causes of whole machine vibration, and Rotary motions of conveying mechanism, fan and threshing cylinder contribute secondly to the vibration of the whole machine. During harvesting in the field, vibration strength of the whole machine decreases and vibration strength of 7 measuring points decrease remarkably except for seat support. On full throttle no-load mode the vibrating frequency of engine is 71.78Hz, excitation frequencies of vibrating sieve, cutter, fan, drum I and drum II are 6.35 Hz, 8.79 Hz, 19.04 Hz, 12.70 Hz and 23.44 Hz separately. During harvesting in the field, several excitation frequencies of the main working parts overlap and it is difficult to identify. The research result provides a reference for improving driving comfort level and working reliability.