STUDY ON THE OPERATING EFFECT OF STRAW CRUSHING AND SPREADING DEVICES ON SINGLE AXIAL FLOW HARVESTERS

To identify the specific manifestations and influencing factors of the poor straw crushing and spreading effects in Northeast rice-growing areas, this paper focuses on the straw crushing and spreading device widely used on single axial flow harvesters. Experimental and theoretical analyses were conducted. The results indicate that the existing straw crushing and spreading devices, under different operating speeds and with various active blade types, exhibit crushing performance, spreading width, and spreading uniformity significantly below standard values. The primary issues are straw clumping, insufficient straw crushing, lateral bias in spreading, and inadequate spreading width. By establishing a theoretical model, the analysis reveals that the straw crushing effect is related to the characteristics of the straw itself, such as blade rotational speed, cutting angle, and support angle. In contrast, the spreading effect is associated with the motion direction of the straw leaving the threshing drum, straw ejection speed, and the arrangement of deflector plates. This paper clarifies the elements that need improvement in the operational effectiveness of the straw crushing and spreading devices attached to combine harvesters, providing a theoretical basis for subsequent enhancements.