Experiment Study And Application Of Portable Rice Combine Conical Threshing Mechanism

Rice is among the most important crops in China, about430million mu iscultivated every year, about60%of the rice is distributed in the mountainous hillyregion, as limited by the type, the harvesting of the rice mechanization level is very lowwhere is hilly region. In order to meet market demand, we must develop a new kind ofcombination of portable rice combine, which is power consumption、low mass、smallsize、easy to dismount. This article aims to get a new conical threshing mechanismwhich is applied to the combination of portable rice combine.The threshing mechanism for this task includes small tapered angle threshingcylinder、Semi-cylindrical woven screen concave plate、header cap、front butt plate andbehind butt plate，This dissertation presents the operating principle of typical threshingand operating principle of spiral conveyor. its guiding apparatus adopts a pair of spiralconveyor, instead of using the conventional gripping delivery, threshing mechanism isto blow rice ear comb and brush，and cooperated with concave plate screen and headercap, afterwards, threshing and separation are done, straw is discharged outside alongthe axial in the end. By using the self-designed conical threshing mechanism, the indoorprototype experiment is carried out. Taking the threshing total loss rate and impurityrate as indicators, by the comparison test between the retaining plate height and thetooth trajectory length, the orthogonal regression experiment was carried out taking nailtooth height, entrance threshing gap, screen size and drum speed as the test factors.Finally the optimal parameter combination has been obtained: On the condition of spiketooth depth of25mm, entrance concave gap of15mm, exit threshing gap of9mm,roller speed of750r/min, mesh size of15mm, seed retaining plate height of20mm andteeth trajectory length12mm, when the cylinder length is650mm, the total threshingloss rate is2.23%and the impurity rate is5.29%; when the threshing cylinder length is800mm, the total threshing loss rate is1.28%and the impurity rate is6.65%.The topic of optimization of the technological parameters has been applied to design portable rice combine, not only the model size is greatly reduced，but alsoportable rice combine guarantees the threshing performance. The research in thispaper has strong utility value of generalization.