Abstract Rice seeding in hill is beneficial to the growth of rice in the field and the increase of rice yield. However, rice seed metering device usually uses multiple rice seeds for sowing, which is difficult to form a hill. To improve the performance of rice seeding in hill, the seed throwing mechanism of the rice pneumatic seed metering device with adjustable seeding rate was study, and the trajectory of seed throwing was analyzed theoretically. The equation of seed throwing trajectory was established. The distribution of sucking holes on the sucking plate was optimized by using asynchronous seed throwing method. The distribution mechanism of seed throwing was studied, and the theoretical trajectory area of seed throwing was established. The actual trajectory area of seed throwing was established by high-speed photography. The theoretical area and actual trajectory area of seed throwing were compared by experiments. The influence factor of errors between the actual and theoretical seed trajectory areas were analyzed. The performance of seed throwing in hill was tested under different positive pressure and different rotational speeds. The optimum qualification rates of different seeding rates were 97.34%, 90.36% and 87.36% respectively. These were 10–17% higher than the original qualification rates of seed throwing. The experimental results showed that the optimized sucking holes on sucking plate could effectively improve the performance of seeding in hill of seed metering device. This study provided a theoretical basis for the seed throwing mechanism of the rice pneumatic seed metering device, and improved the qualification rate of seed throwing.

中文翻译：

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可调播种量水稻气动排种器抛种机理建模与试验分析

摘要 山地水稻播种有利于田间水稻生长，提高水稻产量。然而，水稻排种器通常采用多颗水稻种子播种，难以形成丘陵。为提高水稻山地播种性能，研究了播种量可调的水稻气动排种器的抛种机构，并对抛种轨迹进行了理论分析。建立抛种轨迹方程。采用异步抛种法优化了吸盘上吸盘的分布。研究了抛种的分布机理，建立了抛种的理论轨迹区。通过高速摄影建立实际抛种轨迹区域。通过实验比较了抛种子的理论面积和实际轨迹面积。分析了实际和理论种子轨迹区域误差的影响因素。试验了不同正压、不同转速下的抛山性能。不同播种量的最佳合格率分别为97.34%、90.36%和87.36%。这比最初的种子投掷合格率高出 10-17%。试验结果表明，优化后的吸盘吸孔可有效提高排种器山地播种性能。本研究为水稻气动排种器的抛种机理提供了理论依据，提高了抛种的合格率。