Abstract: Rape plant is high and large with branches implicated, fried pods, large mechanized harvesting loss in harvest period. In order to reduce the rape harvest loss of combine harvester, the rape cutter of 4LZ-4.0 grain combine harvester was redesigned by lengthening the cutter 450mm, installing 1150mm doubleacting cutter halfdistance stroke vertical side cutting knife, adjusting the reel wheel center position, reducing reel wheel speed to 12-21r/min, heightening 400mm side rear wall and other methods. The field harvest loss comparative experiment of three rape planting modes were carried out on the prototype, the results showed that the rape cutter loss rate was 4.44%, the total loss rate was 6.60% (<8.00%), 45% and 36% lower than before improvement respectively. It has proved that the design has certain production practice reference value for the harvester rape cutter loss rate.

Key words: combine harvester, rape, cutter, loss rate, harvesting machinery

摘要： 油菜收获期植株高大、分枝牵连、易炸荚，机械化收获损失大。为减少联合收割机油菜收获损失，通过加长450mm割台、安装1 150mm双动刀半刀距行程竖侧切割器、调整拨禾轮中心位置、降低拨禾轮转速至12~21r/min、加高400mm侧后围挡等方法，改进设计4LZ-4.0谷物联合收获机油菜割台。对样机进行三种油菜种植模式的田间收获损失试验，试验结果表明，油菜割台损失率为4.44%，总损失率为6.60%(<8.00%)，分别较改进前降低45%和36%。本设计对油菜割台收获损失降低有一定的生产实践参考价值。

关键词: 联合收获机, 油菜, 割台, 损失率, 收获机械