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Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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]

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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]

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]

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)