RESEARCH ON THE TRAY CONVEYING AND OUTPUT DEVICE OF AN AUTOMATIC TRAY PLACEMENT MACHINE FOR MULTI-ROW RIGID RICE SEEDLING TRAYS

To address the issue of height disparity between the output device of the tray placement machine and the seedbed in stacked-tray germination under enclosed conditions - which can lead to vibration and displacement when trays are placed - a slide-type output device with a buffering function equal to the height difference was designed to ensure gentle placement of seedling trays. A three-factor, five-level quadratic orthogonal rotational combination test was conducted using Adams software for simulation analysis. The test factors included the horizontal inclination angle of the tilting frame, the horizontal inclination angle of the sliding plate, and the speed of the seedling tray pusher. Evaluation indices included the qualification rate of tray spacing, the qualification rate of alignment, and the efficiency of tray placement. Test results were analyzed using Design Expert 13 software, and multi-objective parameter optimization was performed. The optimal parameter combination was determined as follows: a tilting frame inclination angle of 15°, a sliding plate inclination angle of 18°, and a tray pusher speed of 0.16 m/s. Field trials conducted to validate these parameters resulted in a 96.11% qualification rate for tray spacing, a 95.89% alignment qualification rate, and a tray placement efficiency of 714 trays per hour - within 1% of the theoretical optimal value. These findings provide a theoretical foundation for the smooth and efficient operation of automatic seedling tray placement machines.