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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.)

In recent years, with the increase in the area of domestic sunflower planting, with the supporting mechanised production system is relatively backward, especially the low level of mechanised harvesting. Currently, the harvesting of edible sunflowers in China mainly adopts segmented harvesting, first cutting the sunflower disc and then inserting it on the sunflower stem to dry for about 7-10 days. After the moisture content of seeds meets the harvesting conditions, mechanical harvesting is used, which is time-consuming, labor-intensive, and causes significant losses, that the serious constraints on the development of the sunflower industry have led to limited reports on the combined harvesting of sunflowers. Therefore, there is an urgent need for mechanized combined harvesting of sunflowers. Due to the thin and short skin of sunflower seeds, while the traditional combine harvester has a long material transportation path after harvesting,thus during the transportation process, the sunflower disc is prone to breakage and the seed skin is easily damaged, leading its economic value greatly reduce, In addition, the severe breakage of the sunflower disc increases the difficulty of subsequent cleaning.Therefore, this study focuses on the problems existing in the mechanized harvesting process of sunflowers mentioned above. Combining the characteristics of sunflowers as high stem crops and easy threshing during the complete maturity stage, this 4KHZ-330 sunflower combine harvester was innovatively designed on the basis of the traditional material process flow of the combine harvester. It achieves the separation of sunflower seeds and impurities on the header, aiming to shorten the transportation path of sunflower discs after harvesting, reduce transportation losses, and reduce sunflower disc breakage. To lay the foundation for improving the cleaning quality follow up,the key component structures and parameters such as cutting threshing integrated type header, cleaning device, and pneumatic conveying device were been designed, and conduct field experiments was conducted to verify the rationality of the design. This article elaborates on the overall design scheme and power transmission mode of combine harvester, and designs key components such as cutting threshing integrated type header, header lifting mechanism, cleaning device, and pneumatic conveying device, and determines their relevant parameters. The machine was equipped with power of 113 kW and working width of 3300 mm,which can complete the cutting, threshing, conveying, cleaning, seed collection, grass collection, and unloading processes of sunflowers. Field experiments were conducted have shown that under three different working gears of low, medium, and high, the total loss rate of the harvester was less than 4.0%, the impurity content of the seeds was less than 5.0%, the damage rate of the seeds was less than 2.0%, and the productivity was 0.40-0.85 hm²/h. The work performance indicators meet the requirements for harvesting sunflowers and are superior to relevant standards. During the work process, the coordination relationship between key components of harvester was stable, the sunflower feeding was smooth, effectively saving manual labor, reducing production costs, and improving work efficiency.This can provide technical reference for the development of subsequent sunflower harvesting equipment. [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.)

A sunflower seed is one of the most important cash crops in oil, food, and feeding. The area of edible sunflower cultivation has steadily increased in China in recent years. It is an urgent need for mechanized and combined harvesting. However, the conventional machinery of edible sunflower harvesting cannot fully meet the large-scale production, due to the low seed selection and adaptability in fields. Among them, the fan-shaker structure is adopted for the current cleaning device in the 4ZK-6 type combined harvester of edible sunflower. It is a high demand to develop a new device suitable for steep slope, where edible sunflower is widely grown. In this study, a cylinder sieve device was designed for the combined harvesting operation under the complex terrain, according to the threshing mixture characteristics of edible sunflower. The size of the sieve aperture was set as 16 mm using the average three-axis diameter and particle size of the edible sunflower seed, broken petiole, and broken sunflower plate in the threshing mixture. The range of the inclination angle was obtained to clarify the effect of the inclination angle of the sieve on the performance of the seed sieve using the size of the stripped material particle. The kinematics analysis of edible sunflower seed was combined with the actual production needs. The structure size of built-in flow-aided spiral blades was determined as follows: the outer and inner diameters were 670, and 500 mm, respectively, while the pitch was 400 mm. A dynamic analysis was performed on the sliding and throwing out of edible sunflower seed on the cylinder sieve surface. The range of velocity was then determined in the cylinder sieve. Software EDEM was selected to determine the axial motion velocity of materials in the cylindrical sieve with the sifting time, and the sifting characteristics of edible sunflower seeds with the size of the selected sifting hole. The single-factor test was carried out to clarify the influence of the inclination angle, the rotational velocity of the cylinder sieve, and the feeding amount on the seed clean rate and loss rate. The threshing mixture of "Sunflower 363" was selected as the research object in Hebei Province and Inner Mongolia Autonomous Regions, China. The optimal intervals of working parameters were determined for each factor. The orthogonal test was carried out using cleaning rate and loss rate as evaluation indexes under SPSS software. Variance analysis showed that the rotational speed and feeding amount of the cylinder sieve posed a significant effect on the clean ratio and loss ratio, whereas, the inclination angle of cylinder sieve installation had a significant effect on the clean ratio, but some effect on the loss ratio. The comprehensive scoring demonstrated that the order of the primary and secondary factors on the cylinder sieve selection was ranked as inclination, the speed of the cylinder sieve, and feeding amount. The optimal working parameters of the cleaning device were achieved in the feeding amount of 0.6 kg/s, the sieve installation inclination of 3°, and the speed of 25 r/min. The bench test indicated that the clean and loss ratios were 98.92% and 1.97%, respectively under the optimal combination. A field test was carried out in Wuchuan County, Inner Mongolia Autonomous Region, China. The test subject was chosen as the "sunflower 363" with the 800 mm+400 mm wide and narrow planting mode, where the plant spacing was 500 mm. Three 20-metre slopes were selected in the steeply sloping areas, in order to verify the performance and adaptability of the cylindrical sieve cleaning device in complex working conditions. Specifically, the clean and loss rates were 96.53%, and 2.08%, respectively, indicating the stable operating performance of the cylinder sieve device. The clean rate of the whole machine was 3.32 percentage points higher than the original fan-shaker cleaning structure, while the loss rate was reduced by 4.11 percentage points. The cylinder sieve device can be expected to effectively improve the performance of edible sunflower combine harvester in complex terrain. This finding can provide the theoretical reference for the structural optimization of edible sunflower harvesting equipment. [ABSTRACT FROM AUTHOR]

When the sunflower combine harvester is operating in the field, the header reel may collide with the sunflower disk in the process of reeling, easily leading to the seeds dropping off the sunflower disk. The surface of the seed is subject to friction force, even damage to the seed hull, during the process of transporting seeds and sunflower disks with the spiral augers and elevator components. In addition, the severe vibration of the header can also cause the straw to shake, resulting the high seed loss. In this study, several experiments were carried out to explore the influence of the header collision and vibration on sunflower seed loss and the influence of the friction on the seed hull damage under different seed moisture content during the harvest period. The proper time of sunflower harvesting was determined to balance the contradiction between falling seeds loss and seed hull damage. The harvesting effect was also improved in the sunflower combine harvester. Firstly, a series of investigation was conducted to determine the impact of the collision of the reel web on the sunflower plate falling seeds loss during reeling, while the effect of the screw auger conveying on the hull damage of the sunflower seeds. The results show that the higher the moisture content of the seeds during harvesting, the greater the binding force between the seeds and the sunflower plate was, while the easier the damage of the seed hull was, and the greater the damage rate of the seed hull, was. There were less likely the seeds to fall off when they were hit. The optimal harvest time was considered to balance the comprehensive influence of the seed loss rate and the seed damage rate. Secondly, the weights of the sunflower plate falling seeds loss rate and the seed hull damage rate on the harvesting effect were 0.54 and 0.46, respectively, according to the requirements of sunflower harvesting on the loss rate and skin loss rate. The objective function was optimized with the Matlab platform. Thus, the moisture content of about 10.8% (9%-13%) was the best harvest period for sunflowers. Finally, the Default Shaker hydraulic shaking,table was utilized to clarify the influence of vibration excitation in the main vibration frequency range of combine harvester on the falling seeds loss of the sunflower plate. The results show that the first-order vibration frequency was 7 Hz with a great impact on shattering, and the second-order vibration frequency was 19 Hz. The loss rate of sunflower plate shattering was 1.5% at most under the excitation of the first-order vibration. However, the theoretical vibration frequency of the reciprocating cutter was 7.08 Hz, similar to the first-order vibration frequency of the sunflower plant. The vibration excitation of the reciprocating cutter can cause the resonance of the sunflower plant during harvesting in the field, resulting in seed loss. The finding can also provide a strong reference to optimize the operation parameters of the key components of the header in the sunflower combine harvester. [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.)

Difficult picking is often found in the harvesting of fresh chestnut, particularly in the low efficiency and high labor cost of manual harvesting, as well as the high risk of high-altitude picking. However, only a few research focused on this field in China. In this study, a beating-type fruit dropping device was proposed for a chestnut harvester, according to the characteristics of chestnut trees and the planting mode of Chinese chestnut. The overall structure and working principle were also introduced into the design of the chestnut harvester. Two situations were included to separate the chestnut fruit from the branch. When the beating strips hit the fruit, the beating force was directly transferred to the fruit. As such, the fruit was separated from the branch, if the beating force was greater than the binding force between the fruit and the branch. When the beating strips hit the branch, an inertia force was transmitted from the branch to the fruit, where the chestnut was separated from the branch to complete the chestnut harvest, if the inertia force was greater than the binding force. A beating mechanism was also designed as a crank-rocker without quick returning, in order to ensure the overall performance of the machine, and the stability of the fruit dropping device in the process of operation. The size of the crank-rocker mechanism was also determined under the optimal conditions. A kinematic model was established for the crank-rocker mechanism, further to obtain the kinematic relationships of angular displacement, angular velocity, and angular acceleration of the rocker. A dynamic simulation was also performed on both sides of the beating device in the crank-rocker mechanism. It was found that the motion of the rocker was symmetrical in terms of the motion curve, where the swing angle of the rocker reached 60° suitable for the stability requirements. Furthermore, the variation of separation force between chestnut fruit and branch was obtained at different tension angles. Specifically, the separation force decreased gradually with the increase of tension angle in the range of 0°-90°, where the maximum separation force was 65.24 N at 0° tension angle. The collision model between the beating strips and the branch was established to determine the main factors affecting the beating force, including the speed of the motor, the length of the beating strips, and the beating angle. A three-factor three-level orthogonal test was conducted, where the materials of beating strips were selected as poly urethane, low-density polyethylene, iron sheet, and glass fiber. The results show that the maximum beating force was only 44.31N for the polyurethane, while the maximum separation force of chestnut fruit and branch was 65.24 N, indicating that the maximum beating force provided by polyurethane was less than that of chestnut fruit and branch, fail to meet the requirements of beating force for fruit picking. The maximum beating forces of iron sheet and glass fiber were 87.46 N and 94.03 N, respectively. Nevertheless, the excessive force was easy to damage chestnut branches. Fortunately, the maximum beating force of low-density polyethylene was 70.71 N, similar to that of chestnut fruit and branch (65.24 N), indicating the best beating material. In this case, the optimal combination was achieved, where the motor speed of 600 r/min, the beating strip length of 350 mm, and the tapping angle of +20°. A field test of the chestnut harvesting machine was carried out to verify each area for harvesting. Several areas were selected on the chestnut tree for the harvest experiment after the positioning structure moved the fruit dropping device. The field test shows that the beating force provided by the fruit dropping device can effectively beat the chestnut fruits within 10s, where the fruit drop rate was 90.1%, while less damage to the chestnut trees. Consequently, the beating-type fruit dropping device can fully meet the harvest requirements of chestnut fruits. The finding can provide a strong reference for further research and development of chestnut harvesting machinery. [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.)

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.)