全膜双垄沟播直插式玉米播种装置双面凸轮的设计

针对全膜双垄沟播直插式玉米播种装置的核心部件单面凸轮控制的穴播杆水平位移不精确、振动较大等问题,设计采用双面凸轮代替。在沟播机虚拟样机基础上,生成双面凸轮内外接触轨迹曲线,由于生成的双面凸轮轨迹在奇点处过渡急剧,会造成凸轮与顶杆运动过程中冲击过大而无法实现设定的运动,甚至卡死,对轨迹过渡奇点段进行了圆弧过渡优化,对优化前后的凸轮在x、y方向位移曲线进行了对比,相应位移量较小。经沟播机虚拟样机仿真,双面凸轮驱动下的成穴器在入土前不会与地面发生干涉;对双面凸轮进行的冲击力和拉力作用下最大形变和应力进行分析的结果表明,双面凸轮在受到最大冲击力和拉力时最大变形量为0.092 mm,且其最大Von–Mises应力均远低于67 MPa,应能满足直插式玉米全膜覆盖双垄沟播机作业需求。

Comparing the Contents of Embedded Subtitles to Remove Duplicate Video

In order to improve the precision of the horizontal displacement and reduce the vibration of punching rod controlled by single-track cam a double-track was designed for direct insert corn planting furrow seeder for whole plastic-film mulching on double ridges. Based on the virtual prototype of direct insert corn planting furrow seeder, the inside/outside contact curves of double-track cam were generated to design the cam. The sharp singularity transition in the contact curves of double-track cam could cause too vigorous impact between the cam and the rod to achieve the expected movement, even completely stop. So it is necessary to optimize the singularity transition by arc curve. The displacement in x, y direction was little changed for the curves before and after optimization. There was no interference between the hole former driving by the double-track cam with the ground by the simulation of virtual prototype of direct insert corn planting furrow seeder. By the analysis of the maximum deformation and stress of the double cam under the maximum impact and tension, it is found that the maximum deformation is 0.092 mm and the biggest Von-Mises stress was 19.8 MPa, far less than 67 MPa. The double-track cam can meet the demand for the operation of direct insert corn planting furrow seeder for whole plastic-film mulching on double ridges.