多作物收割机割台的设计与试验

Design and test of multi-crop harvester header

针对作物收获时农机具利用率低且存在因振动造成割台损失大、工作稳定性差等问题,以4LZ-3.2型水稻联合收割机为研究对象,设计一种面向水稻、玉米、大豆联合收割的多作物割台,确定割台伸缩、接穗板及连杆机构的具体参数,开展割台振动试验和田间收获试验。通过增设液压缸伸缩机构和基于连杆联动的接穗板变换机构来满足多作物收割要求,理论分析确定玉米收获时割台伸缩长度为200 mm;接穗板的折角为15°、总长为300 mm、宽度为30 mm、折起长度为135 mm、厚度为5 mm;连杆Ⅰ长度为330 mm,连杆Ⅱ长度为70 mm,拉杆长度为530 mm,转动杆长度为510 mm;部件所用材料均为Q235钢板。振动试验结果表明:在发动机低转速(1800 r/min)时割台振动以收割机共振为主;高转速(2600 r/min)时以振源影响为主,其中切割器的往复运动是主要振源;物料流的喂入对割台不同位置的振动强度受挠度影响很大,而喂入量的变化对割台振动影响不大。可见,所设计割台损失较通用收割机割台变化不大。田间收获试验表明:收割机行驶速度为0.6~1.4 m/s时,收割机收获水稻、玉米、大豆时的割台损失率平均值分别为0.42%、0.49%、0.31%,均小于相关国家标准,表明所设计的多作物收割机割台对3种作物的适应性较好,伸长割台对作物损失影响较小。

With an attempt to solve the problems in crop harvesting including the low utilization rate of agricultural machinery and tools,header loss and poor working stability caused by vibration,we designed a new multi-crop header for combined harvesting of rice,corn and soybean for 4LZ-3.2 rice combine harvester with optimal parameters of header expansion,scion plate and linkage mechanism.The header vibration test and field harvest test were carried out.By adding a hydraulic cylinder expansion mechanism and a connecting rod linkage based scion plate transformation mechanism to meet the requirements of multi-crop harvesting,theoretical analysis determined that the header expansion length during corn harvesting was 200 mm,the scion plate had a folding angle of 15°,a total length of 300 mm,a width of 30 mm,a folding length of 135 mm,and a thickness of 5 mm.The length of connecting rodⅠwas 330 mm,the length of connecting rodⅡwas 70 mm,the length of pull rod was 530 mm,the length of rotating rod was 510 mm,and the material used for the components was Q235 steel plate.Vibration test showed that header vibration was due to harvester resonance at low engine speed(1800 r/min),and vibration source at high engine speed(2600 r/min),the reciprocating motion of cutter was the main vibration source of header.The feeding of material flow had a great influence on the vibration strength at different positions of the header by deflection,and the change of feeding amount had little influence on the vibration of header.The loss of the designed new header had little change compared with the common used header.Field header loss test showed that when the driving speed of the harvester was 0.6-1.4 m/s,the average loss rates of rice,corn and soybean field headers were 0.42%,0.49%and 0.31%,respectively,which were lower than the relevant national standards,suggesting the adaptability of the universal header to the three crops and extending the header had a relatively small impact on crop losses.