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In most areas of Xinjiang, edible sunflower is harvested in stages by means of transplanting plates for drying and taking plates for threshing. In some areas, edible sunflower harvesters are used for field operations, and problems such as edible sunflower plate leakage and grain loss exist in the process of harvest, which seriously hinder the development of edible sunflower scale and industrialization. In order to solve these problems and improve the harvesting efficiency of edible sunflower machine, this paper conducted a field survey on planting mode and biological characteristics of the edible sunflower in Xinjiang, and summarized the harvesting mechanism of edible sunflower. Starting from the operation path of manual harvesting sunflower tray, and combining with the requirements of field harvesting, a kind of collecting station for edible sunflower was designed. Field experiment was carried out to verify the field performance of the collecting station for edible sunflower. The specific research contents and conclusions were as follows. First of all, experimental study on the physical characteristics of edible sunflower was made during harvest in Xinjiang. It mainly included the determination test of the basic physical quantity, the friction characteristic test and the impact seed falling test. The average moisture content of edible sunflower plate was 38.97% and that of culm was 65.49%. By the bevel method, we got the friction angle between the dish and the steel plate was about 29.2°, the static friction coefficient was 0.56. The experiments were carried out to obtain the operating parameters with less loss of sunflower plate, which provided the theoretical basis for the field operation of edible sunflower harvesting platform. Secondly, in this paper, the whole plan of the collecting station for edible sunflower was determined, and the structural design and parameter analysis of the key devices were carried out. This paper designed a kind of station for collecting edible sunflower by imitating the manual way of picking dish. The whole machine structure was mainly composed of the pick-up device, conveying device, collecting dish box, walking device, power transmission system and frame. By analyzing the segmented path map of manual picking-up and parabolic dish, and combining the working posture of the pick-up device in each harvesting stage, the bionic pick-up device was designed and the basic structural parameters were determined to achieve the goal of bionic dish taking action and the shortest parabolic dish path. The 3D model of the pick-up device was established and the kinematics analysis were carried out to obtain the displacement, speed and acceleration change rules of the pickup device's disk-bar and determined the best structure and working parameters combination of the pickup device. The conveying device was designed and the speed of it was calculated to be 92 r/min, the theoretical productivity was 2.19 t/h. By analyzing the power transmission system, we got the transmission law of chain. The field harvest test finally was carried out with the total harvest loss rate as the test index, the height of the plug plate, the rotational speed of the take-up rod and the forward speed of the unit as the test factors. The results showed that the collecting station for edible sunflower could complete the functions of picking up, transporting and collecting. The optimal combination of the collecting station for edible sunflower was that the height of the disc was 650 mm, the forward speed of the unit was 0.88 m/s, the rotational speed of the take-up rod was 23 r/min, and the total loss rate of harvest was less than 5%, which could meet the operation requirements of Xinjiang edible sunflower harvesting. [ABSTRACT FROM AUTHOR]

Sowing opener is one of the key parts of seeders, and its working performance affects the seeding quality. Domestic and foreign scholars have done a great deal of research on sowing openers in terms of traction resistance, soil disturbance, soil return performance and blocking performance. But there are few reports on the research of sowing opener for the integrative structure of ditching, earthing and suppressing. In this paper, an integrated sowing opener, which can be used to ditch, earth and suppress, was designed. It can solve the problems such as large disturbance of soil, insufficient compactness of seed bed soil, and poor uniformity of sowing depth. The combination of its sliding knife, retaining plate and repressing wheel can realize the seeding ditch, the seed falling to the bottom of the ditch, the wet soil returning to ditch, the suppressing wheel suppressing the seeding ditch, and the seed being in close contact with the soil. In this paper, the cutting edge curve is analyzed according to the slip cutting principle. It sets the cutting edge curve equation as parabola equation to deduce the conditions which can satisfy the needs of the slide cutting. That is, the slip angle is larger than the friction angle. The final result shows the range of the slider slip angle is 25°-65°. Based on the analysis of the principle of soil reflux after the operation of the trench opener, it can be seen that the change of the obliquity angle of the retaining plate affects the soil disturbance and the soil reflux, and the range of the inclination of retaining soil plate is 0-12.4°. According to the agronomic requirements, the range of soil compactness required for seed growth is 30-50 kPa, and the spring deformation amount is calculated to be 9-15 mm. Finally, the influencing factors can be determined. They are the slip angle, the slope of the retaining plate and the deformation of the spring. The slider slip angle, inclination of retaining soil plate and deformation variables of spring were selected as test factors. Soil compaction and soil disturbance were selected as experimental indices. The optimal parameter combination of the integrated seeding opener obtained from the soil bin text of optimizing the structural parameters was as follows: The slider slip angle was 44.6°, the inclination of retaining soil plate was 3.2° and the deformation variable of spring was 11.8 mm. In order to verify the operation performance of the integrated seeding opener better, field contrast tests were carried out with a double-disc opener and a sharp angle opener under the optimal parameters. The variation coefficient of sowing depth, soil compactness, soil disturbance and backing soil quantity were selected as test indices. The experimental results showed that variation coefficient of sowing depth of the integrated opener was 6.03%, which was 32.4% lower than that of the double-disc opener and 25.2% lower than the sharp angle opener. When the integrated opener was operated, the seeds fell into the ditch prior to the soil, which improved the seeds depth uniformity. The soil compactness was 38.6% higher than that of the double-disc opener and 62.9% higher than that of the sharp angle opener after the working of integrated opener. The suppression part of the integrated opener suppressed the ditches, after the soil-covering ditches were suppressed again by suppressing wheels of the seeder, which increased the soil compaction of the seed bed. The amount of soil disturbance generated by the integrated opener was 16.3% lower than that of the double-disc opener and 36.5% lower than that of the sharp angle opener. But its backing soil quantity was 29.9% higher than that of double-disc opener and 61.5% higher than that of sharp angle opener. Therefore, the integrated opener has little disturbance to the soil. In general, the integrated opener can improve the seedbed environment, enhance soil compaction and improve the uniformity of seeding depth. Besides, this type opener provides an integrated reference for the design of sowing openers. [ABSTRACT FROM AUTHOR]

In recent years, the pneumatic centralized fertilizing and seeding methods were developing rapidly. The pneumatic centralized fertilizing system was mainly used for layered fertilizing operation. The fertilizing pipes of the fertilizer discharging system were connected with the fertilizer outlet of the layered fertilizing shovel. Under the actions of air flow, the fertilizer was transported to the outlet of the fertilizing shovel quickly and remotely, so as to realize the layered application of the fertilizer in the soil. In this paper, in view of the problems such as the fertilizer falling into the inlet was not smooth and the airflow velocity at the outlet was too high, which leading to fertilizer bounce and dust when the fertilizer discharging system and layered deep fertilizing shovel were combined, the relationship between the structure of each part of the fertilizer discharging system and the working parameters was studied through the test-bench of the pneumatic centralized fertilizer discharging system, and the structure of the fertilizing system was optimized. An air-fertilizer separation device was designed, which was installed between the distributor outlet and the fertilizer discharging pipe of the layered deep fertilization shovel, part of the airflow from the fertilizing system was discharged by the air-fertilizer separation device in advance to reduce the airflow velocity at the fertilizer outlet of fertilizing system. The structure and basic working parameters of each component of fertilizing system were determined through theoretical analysis and parameter calculation. In specific, the airflow velocity of the fertilizing system inlet should be greater than 25 m/s, the diameter of the air-fertilizer conveying pipe, fertilizer inlet and fertilizer outlet was 76, 55 and 20 mm, respectively. The main factors affecting the airflow velocity at fertilizer outlet and inlet of fertilizing system were also determined through analysis. Taking the exhaust outlet area of the air-fertilizer separation device (A), the airflow velocity of the fertilizing system inlet (B) and the fertilizing rate (C) as the test factors, the quadratic regression rotary orthogonal platform experiment was conducted. According to the test results, the mathematical regression model between the test indexes and the influencing factors was established. The results showed that the exhaust outlet area of air-fertilizer separation device, airflow velocity of the fertilizing system inlet and fertilizing rate had a significant effect on airflow velocity at fertilizer outlet of fertilizing system, and exhaust outlet area of air-fertilizer separation device had a significant effect on the airflow velocity at inlet of fertilizing system. The optimized parameters were conducted by fitting and optimizing the test results. It was obtained that airflow velocity at fertilizer outlet, fertilizer inlet of fertilizing system was 5.91 and 3.94 m/s, respectively, the exhaust outlet area of the air-fertilizer separation device, airflow velocity of the fertilizing system inlet and fertilizing rate were 798.0 mm², 28.10 m/s and 0.28 kg/s, respectively. The verification test results showed that the airflow velocity at fertilizer outlet and fertilizer inlet of the system was 6.02 and 4.11 m/s, the fertilizer at the inlet of the fertilizer discharging system falled smoothly and stably. [ABSTRACT FROM AUTHOR]

For transplanting vegetables plug seedlings, it is difficult to directly pick up seedlings from the tray cells. Damages of root lumps of plug seedling happen all the time in extracting. In this paper, a root lump loosening mechanism using air jets to eject vegetable plug seedlings making for transplanting was designed and evaluated. It consisted of air jets, a linear module, a double-rod cylinder, a control system and some other supporting parts. The step transmission of the air jet along the horizontal direction was performed using the linear module, which was a synchronous belt system. The air jet′ motion along the vertical direction up and down for ejecting plug seedlings was moved by the double-rod cylinder. For high blowing rates, wholes rows of air jets aiming for each drain hole was designed. In this arrangement, the seedlings could be loosened row by row. With a row of air jets blowing the seedling plugs from the drain holes of the tray cells, air pressures along with the force of the plungers effectively loosened seedlings. It would be good for manual pulling seedlings or automatically picking up seedlings from the tray cells. Based on the integrated design and analysis, the air pressure range of succeeding in loosening seedling plugs was 0.098-0.235 MPa using the air jet at the diameter of 5 mm. Under this condition, the seedlings appeared to be most effective in the loosening and not in destroy of the root soil. Meanwhile, the air jet could eject each drain hole at the bottom of the 128-cell tray. Being the first prototype, its optimal machine parameters were examined under various conditions. In the optimum tests, it was found that the air pressure of the air jet plungers exerted the greatest effect on the integrated ratio in loosening seedling plugs, and followed by the moisture content. Other factors such as the seedling age, the air flow rate and the air jet with sponges or not had no significant effects on the integrated ratio in loosening seedling plugs. In reality, it would probably be a moderate air blast for blowing of the plug seedlings from the tray. If the moisture content of root lumps of the plug seedlings was less than 55%, the cohesion forces between the roots and the tray cell walls would increase. In this case, wetting the roots might serve to reduce the adhesion making for blowing. For cucumbers seedlings, when the air pressure of the air jet plungers was 0.2 MPa, the root zone moisture was 55%-60%, the seedling age was 25 d, the airflow circuit was fully open at the outlet of 4 mm, and the air jet had no sponges, the best intact rate succeeding in loosening root lumps of plug seedlings was achieved. Finally, the overall loosening performance test was carried out. The intact rate of seedling and root lump in loosening root lumps by blowing was more than 96%. It needed about 48 s for finishing loosening the whole tray of plug seedling. The loosening mechanism using air jets to eject vegetable plug seedlings has a good performance, which can meet the actual requirements. [ABSTRACT FROM AUTHOR]

The widely use of plastic film mulching technology in agriculture increase crop yields and farmers' income. However, with the extensive use of plastic film, the residual film in the soil is also accumulating yearly, and the accumulated residual film is hard to be removed from soil. If the residual film in soil plough layer can-not be timely treated, it will lead to soil fertility decline, resulting in crop yield reduction and soil contamination. Therefore, it is an urgent issue to remove the residual film from soil, especially in the tillage layer. In order to solve the problem of remnant film recovery, according to the characteristics of the remnant film recovery machine, and according to the requirements of the agronomy of plastic film recovery, a chain-tooth residual film recovery machine is designed and manufactured. It is expected that the transport of membrane-soil, reverse separation of membrane-soil and membrane-collecting process can be completed. In this paper, we studied the influence of the parameters of the reverse membrane-soil separator of the chain-tooth residual membrane recovery machine on the separating effect of the membrane-soil. By analyzing the influence of the parameters on the performance of the reverse membrane-soil separator of the chain-tooth residual membrane recovery machine, the optimal working parameters were obtained, which could provide reference for the follow-up study and optimization of the membrane-soil separator. Aiming at the problems of poor mechanical properties of residual film deposited in the soil plough layer for many years, difficult separation of membrane and soil, and low recovery rate of residual film debris, a chain-tooth residual film recovery machine was designed. The main working parts of the machine are picking up device and membrane soil separating device. The working depth of the machine is 0-150 mm. The pickup device completes the membrane pickup and conveys the soil with the plastic membrane. Then the residual membrane is separated by the reverse membrane soil separating device, and finally the residual membrane is transported to the membrane collector. Taking angular velocity of pickup device, angular velocity of membrane-soil separator and angle of membrane-soil separator as experimental factors, quadratic regression orthogonal test of three factors and three levels was carried out in this study on chain-tooth residual membrane recovery machine with response values of residual membrane recovery rate and soil content. The response surface model of each factor was obtained by experiment, and the influence of each factor on the operation effect was analyzed and optimized. The results showed that the order of the factors affecting the recovery of residual membrane was: angle of membrane-soil separator > angular velocity of pickup device > angular velocity of membrane-soil separator. The order of the factors affecting the soil content was: angle of membrane-soil separator > angular velocity of membrane-soil separator > angular velocity of pickup device; and the optimized results were tested. The results showed that the recovery rate of residual membrane was 81.12% and the soil content was 34.83% when the angular velocity of the pickup device was 42 rad/s, the angular velocity of the membrane-soil separator was 57 rad/s and the angle of the membrane-soil separator was 37°, and the relative error between the experimental value of each evaluation index and the optimized value of the model was less than 5%. The reverse membrane-soil separator can solve the problems of difficult membrane-soil separation and low recovery rate of residual membrane fragments. It can provide a reference for further research and optimization of membrane-soil separator mechanism of residual membrane recovery machine. [ABSTRACT FROM AUTHOR]

In annual double cropping areas in northern China, the straw is directly returned to the field after maize harvest, and the wheat is sown by no-tillage planter. However, the high water content and strong toughness of maize straw result in the low qualification rate of traditional rotary flail knife type returning machine, which can easily lead to straw blocking and thereby affect wheat sowing quality. To address the above problems, in this paper, a chopping method based on the principle of four-bar linkage mechanism was put forward. The maize straw was chopped using ground as the support. A chopping-type straw returning machine, composed of the frame, pressure roller, transmission device and straw cutting device, was developed. The pressure roller was located at the front of the machine, and was designed to press the standing or lying straws forward in the direction of machine movement. The cutting device was at the back of the roller, and was designed to cut the lying parallel straw into segments. To avoid straw blocking, maize straw was chopped into segments with the length less than 6 cm, and the length was half of the narrow row spacing of wheat. Based on theoretical calculation and motion simulation, the size of 4-link mechanism of cutting device was designed and the cutters' movement trajectory was optimized. In 4-link mechanism, the minimum transmission angle was 70°, the maximum swing angle of rocker was 20°, the eccentric distance of eccentric wheel was 80 mm, and the lengths of cutter holder (connecting rod) and rocker were 267.375 and 460.702 mm, respectively. The distance between the rotation center of eccentric wheel and the hinge point of rocker on frame was 526.627 mm. According to the finite element static analysis by using ANSYS software, the maximum stress of the cutter was calculated as 162 MPa generated near the bolt holes on both sides, which met the design requirements. The field performance experiment was conducted in Hebei Province to compare the chopping-type straw returning machine and traditional flail knife type machine. The comparison and research objects included the unqualified rate of straw length, working stability, soil physical property and the subsequent sowing operation effect. The experiment results showed that the average length of the straw with the designed machine was 4.8 cm, the unqualified rate was 6% and the coefficient of variation was 0.209, which were all superior to the traditional machine. The vibration of the designed one was slightly larger than that of traditional one with no significant difference, and both of the machines worked stably. The cutting depth of new cutter reached 7.71 cm averagely, and soil bulk density in 0-10 cm depth decreased obviously. The subsequent wheat seeding experiments were carried out, and the results showed that there was no straw blocking during seeding when the seeder operated on the surface on which the chop-cutting straw returning machine worked, and the coefficient of sowing depth was 92.5% and it was significantly higher than another one. This study provides a new equipment for the maize straw returning in the double cropping areas in northern China, and it is also conducive to the popularization of straw returning technology. [ABSTRACT FROM AUTHOR]

With the increasing use of the agricultural plastic film, the pollution it brings is also becoming more and more serious. Therefore, design and experiment on plastic film collector of ridged peanut mean great significance to us, of course, facing huge problems. Mechanical recycling plastic film can overcome shortcomings of the great labor intensity and low efficiency using artificial picking up. However the existing plastic film recycling equipments are generally designed based on experiences and have no precise theoretical researches for components, and there are some issues including unreliable picking up performance and unloading mechanism and serious wear of working parts. This paper focuses on the lack of effective automatic removing mechanism for teeth type residue plastic film collector, and according to this situation, automatic removing and smooth returning mechanism for teeth type residue plastic film collector have been designed. Teeth type residue plastic film collector with self-motion unloading mechanism consists of frame, hydraulic shaft fixture, hydraulic fixing bracket, rake, self-motion unloading square tube, hydraulic device, and self-motion unloading scraper. The stability, reliability, and returning smoothness of the motion of the parallel 4-rod linkage mechanism are analyzed. We design a variety of different forms of squeegees to test, and at last find the best form of squeegee named V-shaped. The key part of the mechanism is focused and the stress analysis is performed. Teeth are persistently distorted when they are working. We design 3 types of squeegees including horizontal squeegee, U-shaped squeegee, and V-shaped squeegee, and at last we find the V-shaped squeegee can ensure that teeth are put back in origin place, so it can achieve the best results. The design and innovation of the hydraulic system are also important. We choose single-rod hydraulic cyclinder of 45# steel, the size of hydraulic cyclinder diameter is 40 mm, and the size of piston rod diameter is 25 mm. We use the stress analysis on squeegee, and the movement analysis on planar linkage, and find the movement track of the squeegee at last. Based on this, the objective function and constraints are determined, and the major influencing factors of teeth type residue plastic film collector with self-motion unloading mechanism are the space between teeth and squeegee, squeegee angle, and automatic removing mechanism angle. We do experiment in Jiaozhou, Qingdao, China, the previous crop is peanut, and moisture content of soil is 16%. The experiment and response surface analysis are done for the space between teeth and squeegee, squeegee angle, and automatic removing mechanism angle. The data are then processed, and the parameters are optimized by the response surface method with Design Expert. The response surface analysis of the model shows that the effect of the 3 factors on the primary film removal rate is significant. The order of influencing factors is: the space between teeth and squeegee > squeegee angle > automatic removing mechanism angle. The machine is optimized by the function of optimization of Design Expert, the space between teeth and squeegee is 2 mm, the squeegee angle is 70°, and the automatic removing mechanism angle is 60°. Through the field test, which shows the feasibility of the optimization scheme and will provide theoretical basis for the optimization of related machines. The teeth type residue plastic film collector of ridged peanut has a good film removal effect, which meets the design requirements of plastic recyling machine. [ABSTRACT FROM AUTHOR]

Notoginseng is one of rare medicinal herbs in China, and it is mainly grown in Yunnan Province. Market demand of notoginseng is very large, and hence, until December 2014, the planting area of notoginseng has reached 40000 hm2. At present, the main planting pattern is through manual operation, and the labor intensity is very high and the sowing quality is discrepant. However, there is no precision seeding device suitable for notoginseng. Therefore, the mechanization planting of notoginseng has important practical significance. Notoginseng is planted on small plots of land, the planting density and the requirement of seeding precision are high, so we designed a small sized precision metering device. The liquidity of the seeds is not good and the shape of seeds is irregular for notoginseng, so we chose the pneumatic seed-metering device to adapt to the characteristics of the seeds accordingly. In order to meet the precision seeding requirements of notoginseng planting, a unique pneumatic cylinder-type precision metering device was designed. This device integrated the features of vacuum suction, insulated pressure for seed-clearing and zero speed of seed dropping. In this paper, the main structure and the working principle of the metering device were expounded. The pitch-row of the hollow shaft was determined and the stability of the flow field was ensured by the flow field analysis through the computational fluid dynamics (CFD) software. The key structure parameters were determined through theoretical calculation according to planting requirements. The contrast test of dropping seed indicated that zero speed of seed dropping was necessity. According to the extensive testing combined with the experimental results of relevant scholars, the main factors which affected seeding performance of pneumatic cylinder precision seed-metering device were determined, which were forward velocity, negative pressure and adsorption angle. During the test process, in order to reach zero speed of seed dropping, the installation angle of adjustable insulated pressure plate was changed with forward velocity. The notoginseng seeds in Wenshan were chosen for sowing object. Based on the three-factor five-level quadratic orthogonal rotating combination test method, the influences of forward velocity, negative pressure and adsorption angle on sowing performance were explored. The experimental results showed that the influence of negative pressure on the qualified rate was very significant (P<0.01), and the influences of forward velocity and adsorption angle were significant (P<0.05). The regression equations of the 3 factors were fitted through the processing by Design Expert 8.0.6 (experimental design expert) software. Based on the results of examination, we found that the fitting of the equations was good, the best parameter combination was adsorption angle of 20°, negative pressure value of 660-720 Pa and forward velocity of 0.72-0.76 m/s, and under the optimal condition, the qualified index was greater than 90.2, the missing index was less than 4.9, and the multiple index was less than 5.3. The pneumatic cylinder precision seed-metering device met the standard and requirements by comparing the results with the national standard and notoginseng planting requirements. This approach of research is suitable for the exploitation of notoginseng seed-metering, and provides a theoretical reference for the design of pneumatic cylinder precision seed-metering device for Panax notoginseng. [ABSTRACT FROM AUTHOR]