组合式水稻钵苗育秧盘自动分装装置设计与试验

现有水稻钵苗育秧播种流水线前端的秧盘分离供应尚未完全自动化，特别是软钵盘的分离。为减少劳动力，降低人工成本，本文采用硬托盘与常规育秧软钵盘组合配套，设计一套水稻钵苗育秧盘的自动分装流水线，包括分离软钵盘的指夹式真空吸盘机构、分离硬托盘的滑块连杆机构及其组合而成的套盘机构，用于实现组合式育秧盘中软钵盘和硬托盘的逐个分离和套盘组装，以满足育秧播种流水线前端的秧盘全自动供应。设计一种柔性抓取的指夹式真空吸盘，吸管采用3D打印方式加工，并通过铰链对称安装，模拟人类手指的抓取动作。采用真空吸附的方式实现软钵盘的柔性抓取，不会对软钵盘表面造成损坏。利用ANSYS有限元分析软件对软钵盘受到真空吸盘吸附提升时的变形程度进行分析，确定8组真空吸盘的合理布局。利用ADAMS动力学仿真软件对分离硬托盘的滑块连杆机构进行运动学分析，确定最佳的升降高度以及连杆的开合角度。设计并搭建样机进行试验，试验结果表明：当分离套盘效率为600盘/h时，分离套盘成功率为93.25%,整机运行稳定，符合设计要求，满足一般水稻工厂化育秧播种流水线的工作要求。

Design and Experiment of Automatic Assembly Line for Combined Type Rice Potted-seedling Tray

Current rice potted-seedling production line fails to achieve full automation, especially the separation and supply of potted-seedling tray. A set of combined type rice potted-seedling tray consisting of a soft potted-seedling tray and its supporting hard tray was proposed, and an automatic assembly line was developed. The assembly line consisted of a separation mechanism for soft potted-seedling tray based on finger-clamp vacuum suction cup and a separation mechanism for hard tray based on linkage mechanism combined with a lifting platform, and by combining them to form a tray embedding mechanism. A vacuum suction cup was designed to be installed symmetrically through hinges to mimic the grasping action of human fingers. The vacuum adsorption method was used to clamp the soft potted-seedling tray without damaging the surface of the soft potted-seedling tray. The diameter of vacuum suction cup was determined to be 8mm through calculation. ANSYS was used to analyze the horizontal deformation of the soft potted-seedling tray when it was adsorbed and lifted by the vacuum sucker, and eight groups of vacuum suckers were determined and the reasonable layout was carried out to ensure that the deformation of the soft tray during lifting was less than 1mm. The results of simulation and practical test verified the feasibility of the design. The kinematics analysis of the linkage mechanism was carried out by using ADAMS, and the optimal lifting height of the lifting platform and the opening and closing angle of the connecting rod were determined. Therefore, the cylinder stroke used by the hard tray separation mechanism was selected as 30mm. The control system of the whole machine was designed, and the movement of the whole machine was realized by the combination of stepping motor and cylinder. Through the analysis of motion flow and timetable, the travel switch was selected as the common signal of the two parts of the mechanism to carry out appropriate timing distribution and ensure the highest efficiency. The overall machine was modeled using SolidWorks. Based on the machine model, the prototype was manufactured, and the experiments of separating and embedding tray were carried out. 220V single-phase alternative current was used to power the air compressor and the prototype machine. The pressure regulating valve of the main pneumatic circuit was set to be 0.45MPa. The experimental results showed that the success rate of the hard tray separation mechanism was 97%, and the efficiency was 1000 trays/h. The success rate of separation mechanism for soft potted-seedling tray was 94.25%. When the speed of separation and embedding tray was 600 sets/h, the success rate was 93.25%. The assembly line ran smoothly, and there was no cumulative deviation in multiple tests, which met the working requirements of the rice seeding line.