Abstract:Rice is one of the staple food crops in China and one of the three staple food crops all over the world. The combine harvester has been widely used due to the improved level of riceharvesting mechanization year by year. The longitudinal axialflow threshing and separating device is of widespread use in combine harvester because of its advantages of long threshing time,soft threshing process and good adaptability. However,the device has the disadvantages of high power consumption,broken stalks and high content of impurity. The power consumption of the device plays an important part in the combine harvester. The researches on energy saving and consumption reduction have great significance for developing combine harvester with large feeding capacity,lightweight and high efficiency. In order to reduce the power consumption and blockage of threshing roller,then improve the harvesting efficiency of rice combine harvesters,a new longitudinal axialflow threshing roller with drum-shaped rod-E130tooth was designed based on the idea that the power consumption of the threshing roller can be reduced by improving the uniformity of the longitudinal axialflow threshing roller power consumption along the axial direction. Its structural parameters and motion parameters were determined by analyzing the working principle of the device. The models of power consumption and threshing roller dynamic were established by observing the process of threshing and separation. Based on the EDEM simulation analysis,the instantaneous total torque of rotating shaft of threshing roller with time was simulated and studied with feeding rate of 1.2 kg/s and rotating speed of 1 100 r/min. Taking the total torque of the rotating shaft of the threshing roller as the test index,the performance of the two kinds of rollers was compared with the feeding rate of 0.8 kg/s,1.2 kg/s and 1.6 kg/s. The results showed that the total torque of the rotating shaft of the threshing roller increased with the increase of the feeding rate for the same roller size and motion parameters. When the feeding rate increases from 0.8 kg/s to 1.6 kg/s,the total torque of the drumshaped threshing roller rotating shaft increases from 38.12 N·m to 118.99 N·m,and the cylindershaped threshing roller increased from 60.13 N·m to 189.91 N·m. Under the same feeding rate,the total torque of rotating shaft of drumshaped threshing roller is lower than that of cylindershaped threshing roller. The performance testing platform of a small longitudinal axialflow threshing and separating device was designed and built. The power consumption comparison bench test of two kind structures of threshing roller under conditions consistent with the simulation was carried out. The results showed that the power consumption of drumshaped threshing roller and cylindershaped threshing roller increased from 4.88 kW to 11.20 kW and from 5.58 kW to 12.20 kW in the feeding rate range of 0.81.6 kg/s. Compared with the cylindershaped threshing roller with the same external size,the power consumption of drumshaped threshing roller is lower than that of cylindershaped threshing roller. The results of bench test and simulation are basically consistent. It will provide a reference for designing the drum structure of the rice lowpower threshing roller.