亚洲一区欧美在线,日韩欧美视频免费观看,色戒的三场床戏分别是在几段,欧美日韩国产在线人成

Aiming at the problems of poor uniformity of low sowing quantity precision metering device of vibrating rice seedling tray at present, which is difficult to provide a single row of stable seed flow, a piezoelectric vibrating homogenizing device was designed. The structural parameters of each component were determined by analyzing the vibration principle of piezoelectric vibrator, the dynamics of vibrating plate and the steering of rice seeds. The structural parameters of the vibrating plate were optimized. Taking the depth of the seed storage box, the angle of the steering groove and the direction of vibration as the test factors, the optimization test was carried out in combination with the Box-Behnken test scheme. The results showed that the interaction of the angle of the steering groove, the depth of the seed storage box, the direction of vibration and the angle of the steering groove had a significant impact on the test results. When the depth of the seed storage box was 8mm, the angle of the steering groove was 49°, and the direction of vibration was 29°, and the coefficient of variation of seed evenness was 17.91%. The relationship between the input voltage and the amplitude was further determined by the acceleration measurement bench test. Under the optimal structural parameters, the variation coefficient of uniformity, the qualified rate of sowing and the missed rate of sowing were 18.20%, 94.65% and 0.67%, respectively. The seeding performance test at different uniform seeding speeds showed that when the working voltage was 130~180V, the qualified seeding rate was no less than 94.17% and the missed seeding rate was no more than 0.83%. The adaptability test results of different rice varieties showed that under the three working voltages of 130V, 150V and 170V, the qualified seeding rate was no less than 94.17%, and the missed seeding rate was less than or equal to 1.0%, which met the requirements of precision seedling raising and sowing of super hybrid rice.