Study On The Improvement Of Pneumatic Precise Seeder Of Millet

Millet is the head of Five Grains, there is a general awareness that millet has abundantnutrition. The millet plays an important role in agricultural structure adjustment because ofits character of drought resistance. In recent years, millet industry has got a greatdevelopment. The acreage of millet is smaller than maize and wheat in northern China.However, the development of millet industry is very slow because of a low level ofmechanization. Hill-drop of millet has been proposed in order to reduce labor and improveemergence rate and enhance yield during the millet growing. So it is the most urgent toresearch the millet-seeder which is suitable for its special character. The first prototype’sdesign has made great strides in solving the problem of hole-jam, but it still has some newproblems in adjustability and cavitations. It’s imperative to design the second prototype toresolve these problems.To improve and consummate the first generation prototype, the primary task is research thecharacter of millet. Firstly, we measure six kinds of millet’s dimensions and research itsphysical and mechanical character. They are Jigu－19, Bao－213,An－10-4172, An－4585, Ji－0506and201094. These varieties are grown widely in north of China．Theresearching contents include the measurement of three-dimensional size,1000-grainweight, the natural angle of repose, the angle of auto-flowing of millet. By measuring thesize of three-dimensional and spherical calculation, we conclude that the millet has a bigspan in the size of three-dimensional and liquidity; different kind of millet has similarregulation.Based on the research of domestic precision seeding technology and the summary of thefirst-generation prototype’s problems, we have designed three kinds of seeders, includingunitary circumferential hole type, single-disk gathered keyhole and double-disk slit-type.Finally we choose the double-disk slit-type to apply to overall unit after comparativeanalysis. This paper introduces the seeder’s structure and working principles, it carries onthe kinematics and dynamics analysis, determines its best working condition from theacademic analysis. To detect hill-drop drill’s seeding performance, we have proposedthree-wire methods at last apply detection refined sowing method. This detection method isapplied to the design of the metering device and engine bench test and field experiment;Bench test shows that the influence factors of double-disc slotted-type metering performance is degree of vacuum, slotted width, speed of disk; Field experiment resultsshow that the application of number variation coefficient was24%～39%，average10.5cm,has sliding rate but satisfies the requirement of sow.