Design And Experimental Research Of Drum-shaped Rod-tooth Longitudinal Axial Flow Threshing And Separating Device

Rice is not only one of the main grain crops in China,but also one of the three major grain crops in the global.The combine harvester has been widely used with the level of rice-harvesting mechanization improved year by year.The longitudinal axial-flow threshing and separating device is widespread used 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 impurity content.The power consumption of the device plays an important part in the combine harvester.The research on energy saving and consumption reduction is of great significance for the development of combine harvester towards large feeding capacity,lightweight and high efficiency.Therefore,in order to reduce the power consumption and blockage of threshing roller,then improve the harvesting efficiency of rice combine harvesters,a new longitudinal axial-flow threshing roller with drum-shaped rod-tooth was designed based on the idea that the power consumption of the threshing roller can be reduced by improving the uniformity of the longitudinal axial-flow threshing roller power consumption along the axial direction.The research contents are as follows:(1)A drum-shaped rod-tooth longitudinal axial flow threshing and separating device was designed.Its structural parameters and motion parameters were determined by analyzing the working principle of the device,The models of threshing separation system,power consumption and threshing roller dynamic were established by observing the process of threshing and separation.(2)Based on the EDEM simulation analysis,The axial and radial direction distribution regularities of emerging object and the instantaneous total torque of rotating shaft of threshing roller with time were simulated and studied,under the conditions which feeding rate was 1.2kg/s and rotating speed was 1100r/min.Taking the total torque of the rotating shaft of the threshing roller as the test index,the performances of the two kinds of rollers were compared under the feeding rate were 0.8kg/s,1.2kg/s and 1.6kg/s respectively.The results show that: for the same roller size and motion parameters,the total torque of the rotating shaft of the threshing roller increases with the increase of the feeding rate.When the feeding rate increases from 0.8kg/s to 1.6kg/s,the total torque of the drum-shaped threshing roller rotating shaft increases from 38.12N·m to 118.99N·m,and the cylinder-shaped threshing roller increased from 60.13N·m to 189.91N·m;Under the same feeding rate,the total torque of rotating shaft of drum-shaped threshing roller is lower than that of cylinder-shaped threshing roller.(3)The performance testing platform of a small longitudinal axial-flow threshing and separating device was designed and built,and the power consumption comparison bench test of two kind structures of threshing roller under conditions which consistent with the simulation was carried out.The results show that: in the feeding rate range of 0.8～1.6kg/s,the power consumption of drum-shaped threshing roller increases from 4.88 k W to 11.2k W,and that of cylinder-shaped threshing roller increases from 5.58 k W to 12.2k W.Compared with the cylinder-shaped threshing roller with the same external size,the power consumption of drum-shaped threshing roller is lower than that of cylinder-shaped threshing roller,and the bench test results are basically consistent with the simulation results.