Piezoelectric Vibration Seed Supply Device of Precision Metering Device for Plug Seedling of Super Hybrid Rice

In order to improve the seeding performance of the seed metering device with low seeding rate for plug seedling raising of super hybrid rice, a piezoelectric vibration seed supply device was designed, and a new type of guide vibrating plate with uniform, orderly and single row feeding under the condition of small seed supply was proposed. The working principle of the piezoelectric vibration seed supply device was described, the dynamic model of the vibration device was constructed, the motion mechanism of rice seed on the vibrating plate was analyzed, and its main working parameters were determined. Taking amplitude and depth of seed box as experimental factors, the simulation test, regression and response surface analysis were carried out. The mathematical models of amplitude, depth of seed box and feeding rate, coefficient of variation of seed supply rate and single column rate were established. The results showed that amplitude had a significant effect on seed supply rate, and seed box depth had an extremely significant effect on single row rate. Under the productivity of 600~1 000 plates/h, the mathematical models of amplitude, box depth and single row rate were established. The optimum depth of seed storage box was 9 mm, and the amplitude range was 0.4~0.6 mm. The results of vibration seed supply performance and seed metering performance prototype test showed that when the power supply voltage was 120~140 V, the seed supply rate was 6.1~13.4 seeds/s, the variation coefficient of seed supply rate was 10%~14%, the single row rate was 77.5%~84.6%, and the error between the regression model and the regression model was less than 6%, 9% and 4%, respectively, and the variation coefficient of seed supply rate between columns was less than 4%. The results of prototype test showed that the qualified rate of 1~2 seeds/hole of Tianyou 998 and Shuyou 217 was 95.54% and 94.88%, and the missing sowing rate was 2.47% and 2.96% when the productivity was 600 plates/h, which met the design requirements of low sowing rate and precision sowing of super hybrid rice. The research provided reference for the design of factory precision seeder for plug seedling raising. © 2020, Chinese Society of Agricultural Machinery. All right reserved.