| Rice is the most important crop in China,with an annual planting area of more than three hundred thousand square kilometers.Pot-seedling transplanting technology uses plastic trays to cultivate pot-seedlings.After planting,the soil of the root remains intact.After planting,the soil of the root remains intact,and the tillering is early,and the pot-seedlings are planted on the surface with higher temperature and faster growth,which can effectively increase the rice yield.Therefore,the research of rice pot-seedling transplanting machine has important practical significance to improve the grain yield and realize the machine substitution in China.Based on the analysis of the current research on the rice transplanting machine,and through the field transplanting experiment,it is found that the rotary transplanting mechanism works well,but the delivery condition of the seedling box in the transplanting machine is not satisfactory.The field environment is relatively harsh.After the transplanter goes into the field,problems such as the relative position change of the transplanting mechanism and the seedling box and the failure of vertical seedling-feed are likely to occur.In view of the above problems,this paper proposes a kind of rice seedling tray based on chain conveying;uses non-circular gear and double helix axle to achieve lateral uneven reciprocating movement,which takes into account the success rate of seedling picking and the efficiency of transplanting;uses the longitudinal rice seedling feeding mechanism which can effectively lock,and can still accurately deliver rice seedlings at high speed.The structural design of the transplanting machine is completed,and the finite element analysis,dynamic analysis and experimental research are carried out on the device.The main research contents of this paper are as follows:1)Based on the analysis of the structure and working principle of rice seedling feeding mechanism,the mechanism scheme of the rice seedling box and the rice seedling feeding mechanism was determined.The three-dimensional model of six-row rice pot seedling transplanting machine was established by Solidworks.2)The ANSYS finite element modal analysis of the six-row rice pot seedling transplanting machine was carried out,and the natural frequencies and natural vibration modes of the transplanting machine were analyzed.The frequency of the excitation force of the transplanting machine was compared,and the resonance of transplanting machine during operation was examined.3)The ADAMS dynamic analysis of the six-row rice pot seedling transplanting machine was carried out.And the bearing-force of the transplanting mechanism was analyzed when the mechanism moved.The frame of the transplanting machine was simplified into steel pipe.The deformation of the frame was studied and its influence on the trajectory of the transplanting mechanism was analyzed.The dynamic simulation of the longitudinal seedling feeding mechanism was analyzed,and the restoring force of each part was analyzed,and the structural parameters of the reset torsion spring were designed.The stress of the main and auxiliary support of the seedling box and the movement of the lateral seedling feeding were analyzed to verify the correctness of the seedling box design.When the rotational speed of transplanting mechanism is 120 r/min,the transverse speed of seedling box is the slowest about 38 mm/s and the fastest about 149 mm/s,which meets the requirements of both efficiency and success rate of seedling collection in design.4)The physical prototype of rice pot seedling transplanting test platform was designed and developed,and the experiment of rice pot seedling transplanting mechanism based on clippingplug type was carried out,and the existing problems in the experiment were improved.The results of experiment were analyzed to test the delivery effect of feeding seedlings mechanism.When the rotation speed of transplanting mechanism was set to 50 r/min,the average success rate of seedling was 94.36%,and the success rate decreased with the increase of the speed of seedling.When the rotation speed was 80 r/min,the success rate of seedling was 88.25%.It is verified that the test platform can meet the design requirements well. |
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