Unbalanced Vibration Identification of Tangential Threshing Cylinder Induced by Rice Threshing Process

Zhong Tang,Haotian Zhang,Yuepeng Zhou

doi:10.1155/2018/4708730

Abstract

Unbalanced vibration of tangential threshing cylinder increased the grain loss, shortened service life of the cylinder, and resulted in structural resonance during the rice threshing process. In this paper, the vibration amplitude and frequency of tangential threshing cylinder shaft were tested, and the vibration state of tangential threshing cylinder was identified. The restricted and working modalities of tangential threshing cylinder were solved by ANSYS software. Then, by comparing the resonance phenomenon between the inherent constraint frequency and the rotation speed frequency, the shaft vibration under the idle condition of tangential threshing cylinder was tested and analyzed. According to the axial vibration and axial trajectory of the cylinder, the inherent properties and characteristics of unbalanced vibration were revealed. Test results showed that when the tangential threshing cylinder was at idling and no-load state, the amplitude of vibration in the feed direction of straw flow was -0.049~0.060 mm, and the average vibration amplitude was 0.013 mm. As rice flowed along the tangential threshing cylinder, the vibration amplitude slightly increased. The trend and phase of each trajectory were similar, although the amplitude of each trajectory was different. The tangential threshing cylinder axis trajectory was flat oval. Unbalanced vibration was induced by the rice stalks in the concave gap.

Highlights

During the threshing process of rice, the straw was propelled toward the threshing bar along the circumferential portion of the tangential threshing cylinder
Unbalanced vibration was induced by partial load on tangential threshing cylinder [1]
Unbalanced vibration of tangential threshing cylinder resulted in increased grain loss, shortened cylinder life, and resonance of structure during the process of rice threshing [2]

Summary

Introduction

During the threshing process of rice, the straw was propelled toward the threshing bar along the circumferential portion of the tangential threshing cylinder. Straws were partially loaded on the tangential threshing cylinder. Unbalanced vibration was induced by partial load on tangential threshing cylinder [1]. Unbalanced vibration of tangential threshing cylinder resulted in increased grain loss, shortened cylinder life, and resonance of structure during the process of rice threshing [2]. In order to reduce the vibration of combine harvester, vibration of cutter bar driver was a research hotspot. Chuan-Udom developed 3 types of new cutter bar drivers to reduce the vibration of rice combine harvester [7]. When vibration of cutter bar was reduced, the vibration of rice threshing process was more obvious and serious. Gao et al tested the vibration of crawler-type combine harvester under field harvesting conditions, indicating that significant vibration was caused by the harvesting state [8]

Methods

Results

Conclusion