Abstract
Purpose: In this study, we attempted to analyze, by using a high-speed camera, the cutting shape as a function of cutting speed and feed rate. We compared the differences in cutting shape between domestic and foreign combines. Methods: Experiments were performed using plastic straws, and the results of two combine cutting blades, one from the Daedong Industry and one from Kuboda, were compared. The quality and performances of cutting were measured at three cutting positions: center and 68 cm to the left and right of the center. The feed rates were 0.6 m/s, 1.1 m/s, 1.6 m/s, and the cutting speeds were 600 RPM, 990 RPM, 1,380 RPM. For each speed, the cutting shape was measured three times, and the entire procedure was also repeated three times. Results: In the experiments, the domestic cutting blade achieved better results than the Japanese cutting blade. These results were obtained by studying the combination of feed rate and cutting speed, with the domestic combine attaining approximately 80% performance of the Japanese combine. We believe that additional data analysis is required, obtained from field experiments. Conclusions: The domestic cutting knives achieved better results than the Japanese cutting knives. These results are estimated from experiments conducted with different feed rates and cutting speeds; an in-depth analysis will require experiments in the real field with actual combines and a combination of multiple variables. Repeating the investigation on the length differences, broken and cut angle with various combinations of feed rate and cutting speed, will surely help to find the optimal cutting speed.