| In recent years, the northeast area have been searching for a variety of conservationtillage technology, the technology of stubble mulch farming and alternation tillage isone of the most widely used technology. The technology of stubble mulch farming andalternation tillage adopt high stubble when harvesting operation， because its stubbleretention surface for a long time and alternately tillage，with water keep moisture,reduce the wind erosion and water erosion, the degree of corrosion of stubble is high,increase soil organic and other advantages. The technology of stubble mulch farmingand alternation tillage has the following problem：the height of stubble is high,thusbroken device should be for straw and root at the same time；driving wheel of tractorand tools will be contact with the stubble，so machine vibrations will increase and thephenomenon of off seeder will happen；these problems make traditional machine hardfor to apply to the technology of stubble mulch farming and alternation tillage, thus todevelop a new machine to suitable for the technology of stubble mulch farming andalternation tillage for the northeast and security of national food is great significance.Paper for the problems of planter of the technology of stubble mulch farming andalternation tillage, combining with the characteristics of alternating tillage techniquesand actual conditions of operational in northeast China, through theoretical analysis anddesign experimental and build mathematics model analysis the key components ofplanter in order to design of the technology of stubble mulch farming and alternationtillage.(1) Research of influence factors of stubble cutting resistance and powerconsumption.Paper based on cutting assignment of tool (cutting speed, smooth cuttingAngle, whether fixed straw) and stubble own properties (moisture content of straw,diameter of stubble) as the test factors, the performance of stubble cutting (maximumcutting resistance, cutting power consumption) as the test index, through multiple levelsof single factor experiment found that the influence factor of cutting performance;through the theoretical analysis and other methods to explore operation way of toolcutting has a remarkable impact on stubble cutting performance, Conclusion obtainedfrom the mathematical model and test results to confirm each other, providingtheoretical basis for the design of the part of planter. (2) Research of cutting residues of Operations and theory of mechanism design. Asupported roll cutting type anti-blocking mechanism for no-till planters was designed tocut corn residues (stalks and stubble) during operation of the no-till planter in thestubble mulch field. The mechanism is equipped with both active and passive horizontalrotating parts, which can cut residues more effectively. The active horizontal rotatingparts are used for cutting residues; the passive ones are used for supporting the residuesleft on the surface, making them always lie between the active horizontal rotating andpassive horizontal rotating parts, thus preventing them from being thrown out by thecutting blade during cutting operations. The anti-blocking mechanism cuts the residuesin a supported way, just like a pair of scissors, reducing power consumption duringoperation. The anti-blocking mechanism, which works in a passive way, is placed infront of the opener and has a combined blades structure. Eight slide-cutting blades arefixed on a blade disc and the adjacent blades are mounted on each side of the discrespectively. When it works, the blade disc travels along with the tractor and rotatesabout the blade shaft under the action of the soil resistance. The side-cutting blade onlycuts off the stalk in a slide cutting way without crushing, thus both the rotational speedand power consumption of the blade can be reduced. Stalks can be cut off effectivelywhen the tillage depth is not more than60mm through an optimal design of the curveof the side cutting edge of the slide-cutting blade. Field tests were conducted todetermine the optimal operational parameters, and the rotary quadratic combinationdesign was carried out for the active rotating blade and passive rotating bladerespectively. The regression equations showing the relationship between both factorsand indexes were obtained by using the Design-Expert software. The results showed thebest parameter combination: the rotation speed of120r/min and a turning radius of240mm for the active rotating blade; the turning radius of185mm and a working depth of95mm for the passiverotating blade. Verification tests indicated that the corn stalk andstubble cut-off rate was91.3%and the power consumption of a single blade was145.2W. This study can provide a reference for the design of no-till planters.(3) The research of seed stress and displacement and design of new meteringdevice and leakage alarm device. In order to meet technology of stubble mulch farm-ingand alternation tillage,a soybean seedmeter was designed，which can perform operationsof seed filling，seed cleaning and seed metering，achieving high efficiency，highprecision and low seed damage． The optimal design of structural parameters of theseed-taking block，the key part of the seedmeter，was conducted based on the analysis ofthe working principle of the double-concave seedmeter，which provided a theoretical basis for the design of high-speed and high-performance planters and variableadjustment of seeding rates by adjusting the rotational speed of the seedmeter．Bychoosing reasonable microcontroller, sensors and other components, Rational design ofcircuit and process, design and manufacture for seeding leakage alarm device. Thequadratic general rotary unitized design was carried out with the rotational speed of theseedmeter and tilting angle of the seed-cleaning ring as the experimental factors and thesingle seed rate as the experimental index．Based on experimental data，a mathematicalmodel was built by using the Design-Expert software． Test results showed that theoptimal tilting angle of the cleaning ring was65°，at which the single seed rate of over95%can be ensured when the rotational speeds were less than110r/min．(4) Specificed to the problem that the unsteadiness of the quantity of the soilcovring,and of the intensity of the pressing affect the farm crop yield.This paperdesigned a type of elastic covring-pressing roller, composed by carcass、inner cavity ofcarcass、covering device. Covering device covered soil by elastic flexible skin,of whichadhered soil can be removed by shake. carcass completed pressing operation by owngravity and the pressure from inner cavity of carcass, which achieved the aim atreducing soil disturbance, stabilizing the intensity of the suppression and the quantity ofthe soil covring. Through using ABAQUS software concluded that the largerdisplacement is the covering part when working; maximum strain of wheeland are theintegration of the covering part and wheel, contact area is24000mm2and the force is800N.(5) Research of machine structure of the technology of stubble mulch farming andalternation tillage. Planter is mainly consisted of stubble breaking mechanism,fertilization mechanism, transmission mechanism, in this paper by the method ofstructure optimization design, design a parallel connecting mechanism such as four barlinkage, and it is concluded that the reasonable structure of the machine configuration,through the field experiment, the indicators of machines are more than the indicators ofcontract of National issues, and passed the test of state technology center. |
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