Comparison and Experimental Study of Cotton Stalk Extraction via Nip Roller Based on Nip Motion Trajectory Equation

Abstract

In the field of straw recycling, a cotton straw-harvesting mechanism is an important piece of agricultural equipment. The mechanistic analysis method of the harvesting mechanism is a major focus of research and development in this field. Currently, in the mechanistic analysis of the cotton straw recycling mechanism, the kinematic and mechanical analysis of the recycling mechanism is generally the main focus. There is not a lot of research based on the quantitative analysis between different recycling mechanisms. In this study, a clamped cotton straw pulling mechanism is optimized and designed, and two different pulling structures are designed. In addition, a two-dimensional modeling and analysis method is used to establish the two-dimensional equations of motion of the two pulling mechanisms, analyze the leakage and breakage rates of the two clamping structures, predict the final pulling effect, and verify the results of the field tests. According to the analysis, the belt-clamping side has more uniform clamping stress and a larger clamping contact area than the chain-clamping side, and the tangential stress on cotton straw is smaller. Based on the field-test verification, the band-clamping side had a higher pulling net rate by an average of 19.32% and a lower missed pulling rate by an average of 6.01% than the chain-clamping side. Therefore, it was determined that the main reason for the lower pulling net rate of the chain-gripped side than that of the belt-gripped side was the higher pulling breakage rate, and the secondary reason was the high leakage pulling rate. Thus, the feasibility and accuracy of the analytical method of this study are verified.