农业工程学报
農業工程學報
농업공정학보
2015年
1期
20-27
,共8页
祁兵%张东兴%刘全威%杨丽%史嵩%崔涛
祁兵%張東興%劉全威%楊麗%史嵩%崔濤
기병%장동흥%류전위%양려%사숭%최도
农业机械%种子%优化%排种器%滚筒%充种型孔%清种拨指%清种距离
農業機械%種子%優化%排種器%滾筒%充種型孔%清種撥指%清種距離
농업궤계%충자%우화%배충기%곤통%충충형공%청충발지%청충거리
agricultural machinery%seed%optimization%metering device%rotary drum%seed-filling hole%eliminating finger%eliminating distance
为解决集排式玉米精量排种器低速作业重播严重的问题，设计了一种适用于滚筒式排种器的周向清种装置，对正压滚筒周向清种过程及种子运动过程进行了分析，建立了充种过程的运动学方程，结合种子占据比例的概念分析得出滚筒转速和型孔直径是影响清种效果的主要因素，确定了拨指长度20 mm和拨指末端倒角20°。在JPS-12型排种器性能检测试验台上以郑单958玉米种子为试验材料对集排式精量排种器清种装置的清种效果进行试验，以测试不同清种距离对重播指数和漏播指数的影响，清种距离优化试验表明：在0.25～2.25 mm范围内，清种距离对漏播指数没有显著的影响，但对重播指数、合格指数的影响高度显著。在清种距离大于0.25 mm时，漏播指数随清种距离的减小变化不明显，平均漏播指数0.16%，清种距离为?0.25 mm时，漏播指数急剧上升至5.83%；重播指数随清种距离的减小明显下降。确定优化后的清种距离为0.25 mm，对比试验表明，优化后的排种器在4～12 km/h的作业速度下合格指数均在96%以上，设计的清种装置可以有效降低集排气送式排种器低速作业时的重播指数。该文为进一步研究集排式精量排种器清种装置的结构设计和工作参数优化提供了依据。
為解決集排式玉米精量排種器低速作業重播嚴重的問題，設計瞭一種適用于滾筒式排種器的週嚮清種裝置，對正壓滾筒週嚮清種過程及種子運動過程進行瞭分析，建立瞭充種過程的運動學方程，結閤種子佔據比例的概唸分析得齣滾筒轉速和型孔直徑是影響清種效果的主要因素，確定瞭撥指長度20 mm和撥指末耑倒角20°。在JPS-12型排種器性能檢測試驗檯上以鄭單958玉米種子為試驗材料對集排式精量排種器清種裝置的清種效果進行試驗，以測試不同清種距離對重播指數和漏播指數的影響，清種距離優化試驗錶明：在0.25～2.25 mm範圍內，清種距離對漏播指數沒有顯著的影響，但對重播指數、閤格指數的影響高度顯著。在清種距離大于0.25 mm時，漏播指數隨清種距離的減小變化不明顯，平均漏播指數0.16%，清種距離為?0.25 mm時，漏播指數急劇上升至5.83%；重播指數隨清種距離的減小明顯下降。確定優化後的清種距離為0.25 mm，對比試驗錶明，優化後的排種器在4～12 km/h的作業速度下閤格指數均在96%以上，設計的清種裝置可以有效降低集排氣送式排種器低速作業時的重播指數。該文為進一步研究集排式精量排種器清種裝置的結構設計和工作參數優化提供瞭依據。
위해결집배식옥미정량배충기저속작업중파엄중적문제，설계료일충괄용우곤통식배충기적주향청충장치，대정압곤통주향청충과정급충자운동과정진행료분석，건립료충충과정적운동학방정，결합충자점거비례적개념분석득출곤통전속화형공직경시영향청충효과적주요인소，학정료발지장도20 mm화발지말단도각20°。재JPS-12형배충기성능검측시험태상이정단958옥미충자위시험재료대집배식정량배충기청충장치적청충효과진행시험，이측시불동청충거리대중파지수화루파지수적영향，청충거리우화시험표명：재0.25～2.25 mm범위내，청충거리대루파지수몰유현저적영향，단대중파지수、합격지수적영향고도현저。재청충거리대우0.25 mm시，루파지수수청충거리적감소변화불명현，평균루파지수0.16%，청충거리위?0.25 mm시，루파지수급극상승지5.83%；중파지수수청충거리적감소명현하강。학정우화후적청충거리위0.25 mm，대비시험표명，우화후적배충기재4～12 km/h적작업속도하합격지수균재96%이상，설계적청충장치가이유효강저집배기송식배충기저속작업시적중파지수。해문위진일보연구집배식정량배충기청충장치적결구설계화공작삼수우화제공료의거。
Precision planting is an advanced planting approach and a necessary way to achieve agricultural modernization and also an important step to increase crop yield. Precision metering device is a key component to realize precision planting, which is divided into two types according to its working principle. One type is mechanical metering device and the other type is pneumatic metering device. Compared with mechanical metering device, pneumatic metering device has the advantage of extensive use-area, strong currency, no damage to seed and lower requirement of seed geometry, so pneumatic metering device has been widely applied both at home and abroad. Centralized pneumatic metering device for corn is one type of pneumatic metering device which is applied in large scale planter. It can realize the “one seed metering device to many rows”precise seeding and improve efficiency of seeding. However, there exists a problem that reseeding rate is too high when seeding speed range between 4 km/h and 8 km/h. To solve the problem, a new seed eliminator in radial direction was developed for matching the rotary drum metering device. Analysis was made on radial eliminating process and seed motion process in positive rotary drum and kinematic equations were established of seeds uniform circular motion when seed-filling process finished. According to the analysis, a conclusion was made that the main influencing factors of cleaning effect were speed of the rotary drumωand diameter of seed-filling hole dh based on area occupied ratio conception. In addition, the result showed that the diameter of seed-filling hole dh was the most important influencing factor of occupied area. To meet the demand that seeds should not be blocked when their smallest parts went through the eliminating driving finger, length of eliminating finger lb was determined to 20 mm. Besides, angle of the end eliminating driving finger was determined to 20°based on the maximum static force of friction. In order to determine the proper distance between eliminating driving finger and seed-filling hole, experiments on eliminating distance optimization were done in seed-meter performances test platform of typed JPS-12, and the experimental material was maize zhengdan No.958.Vortex fan was used to supply airflow for the device, and the pressure in working chamber was measured by airflow pressure meter of typed KA33. Results indicated that the eliminating distance in the range from 0.25 to 2.75 mm had no significant influence on the miss-seeding rate, but had highly significant influence on the re-seeding rate and the qualified seeding rate. The re-seeding rate decreased significantly as the eliminating distance range from 2.75 mm to 0.25 mm, with the eliminating distance for negative 0.25 mm. The miss-seeding rate sharply rose up to 5.83%, but the re-seeding rate significantly decreased. The optimized eliminating distance was determined as 0.25 mm, so the eliminating distance was determined as 0.25 mm. Comparative experiment showed that the rate of single seed always kept at above 96% under the optimized eliminating distance as the forward velocity range from 4 to 12 km/h. In detail, the miss-seeding rate generally kept consistent, but the re-seeding rate obviously decreased. The seed eliminator can effectively reduce the multiple rate of the centralized pneumatic metering device. The research can provide a reference for structure design and optimization of working parameters in same type device. The designed device has advantages of seed-and labor-saving as well as the good social and economic benefits.
