气力滚筒式精密排种器结构设计及试验

为解决目前蔬菜田间有序直播生产过程劳动强度大的问题,以排种器的合格指数、重播指数、漏播指数和变异系数作为评价指标,设计出一种气力滚筒式精密排种器。排种器结构采用固定配气盘与排种盘配合的侧面换气方法实行负压吸种和正压排种,每个排种器排种1行,排种位置为水平方向。为探讨精量排种器性能参数的最佳匹配,对吸种负压、排种正压、吹种流量和作业速度在实验室台架进行了单因素和正交试验。试验结果表明:当蔬菜种子直径为1.2~1.8mm时,最佳播种参数为吸种真空度为-7k Pa,清种流量为8L/min,排种气压为0.15k Pa,作业速度为1km/h;此时,合格指数为99.52%,漏播指数0.24%,重播指数为0.24%,变异系数为2.4 4%。设计出的排种器可根据农艺要求通过联轴器连接安装若干个播种单体,实现多行同时播种,行距最小为135mm。

Design and Experiment of Pneumatic Cylinder-type Precision Seed-metering Device

In order to solve the high labor intensity in vegetables ordered direct seeding, designed and manufactured a pneumatic roller-type precision metering device , employing eligible index , multiple index , miss index , variable coeffi-cient as judging indexes.The metering device’ s stationary gas distribution disc match with metering plate, employing side breathing to realize negative pressure seed sucking and positive pressure seed discharging.Each metering device dis-charge one row, feed outlet is positioned in the horizontal position.In order to define the optimum performance parame-ters of precision metering device, single factor and orthogonal experiments were carried out in laboratory, with the experi-mental factors of negative pressure seed sucking, positive pressure seed discharging , flow of blow seeds and operating speed.Experiment indicates that when seed diameter is 1.2~1.8mm, metering device’s optimum performance parame-ters are:the vacuity is -7k Pa, the pressure is 0.15k Pa, the flow is 8 L/min and the operating speed is 1 km/h, the eligible index reaches as high as 99 .52%, both of the multiple index and the miss index are 0 .24%, the coefficient of variation is 2.44%.The metering device can also connected with a plurality of seeding monomer by coupling, to realize multi row sowing at the same time, minimum row spacing is 135 mm.