变容量型孔轮式排种器设计与试验

为了解决针对型孔轮式排种器播量调节困难的问题，在偏心轮型孔轮式排种器的基础上，设计了一种由型孔轮和调节环（舌）组成的变容量型孔轮式排种器，以排种器的转速、调节舌类型、播量调节档位、行进速度、调节舌宽度为变量对油菜种子进行了单因素和多因素试验。试验结果表明：影响排种均匀性、各行排量一致性和种子破碎率的主要因素为排种器的转速、调节舌类型和型孔大小。变容量型孔轮式排种器的转速以30～50 r/min为宜，调节舌类型凹圆头优于平头，型孔长度增大对提高排种均匀性和各行排量一致性及降低破碎率有利。在所设计的结构尺寸条件下，该排种器适应于各类小粒度种子的条播。

Design and test on seed metering device with variable capacity model-hole roller

In order to solve the problems along with adjusting the seeding capacity by using model-hole roller seed metering device, a variable capacity model-hole roller seed metering device was developed based on an eccentric model-hole roller seed meter. The variable capacity model-hole roller seed meter was composed of a model-hole roller and a control ring. Unvaried factor and multivariate factors tests were carried out with five influence factors, which included rotation speed of roller, adjustable tongue, seeding grade, speed and adjustable tongue width. The results showed that the rotation speed of roller, adjustable tongue shape and model-hole size were the key factors which affected seeding uniformity, lines uniformity and broken rate. The seed meter had a preferable performance at the rotation speed about 30-50 r/min; and the concave round tongue was better than the flat one. With length of the model-hole increasing, the seeding uniformity, lines uniformity were improved and broken rate decreased. The seed meter is suitable for drilling for all types of small-size seeds with the designed structural dimension.