水稻气压滚筒式集中排种器设计与试验

Design and experiment of pneumatic cylinder-type centralized seed-metering device for rice

关键词:  水稻  集中排种器  精量播种  排种性能

Key words:  rice  centralized metering device  precision seeding  seeding performance

摘要:

为提高水稻集排式精量穴直播的排种性能，采用正压气流充种、携种和投种原理，设计一种水稻气压滚筒式集中排种器。基于杂交稻机械物理特性参数和精量穴播农艺要求，提出一种气流孔均布于“碗状”型孔的结构，确定其主要结构参数，构建种子在充种和投种过程的力学模型。台架试验研究气流孔直径、滚筒转速和气流孔数量对排种性能的影响，并分析集中排种器对杂交稻品种的适应性。试验结果表明:影响排种性能的主次因素依次为气流孔数量、气流孔直径和滚筒转速；当排种滚筒转速为20 r/min、气流孔数量为7、直径为1.7 mm时，排种合格率为93.33%，漏播率2.50%，重播率4.17%，空穴率0.58%，各行排量一致性变异系数为2.08%。繁优609、F优 498和天优华占3个品种的排种合格率均达到90.00%，漏播率和重播率分别不高于6.00%和5.00%，种子破碎率低于0.20%，各行排量一致性变异系数低于3.00%，说明该排种器对不同杂交稻品种具有较好的适应性。田间试验结果表明，单穴平均播种量为3.56粒，播种合格率89.33%，平均穴距190.3 mm，达到水稻精量穴播排种要求。该研究可为水稻气压滚筒式集中排种器设计提供参考。

Abstract:

In order to improve to the seeding performance of centralized and precision hill direct-seeding for hybrid rice, a pneumatic cylinder-type centralized seed-metering device was designeded based on the principle of positive pressure airflow for assisting seed filling, carrying and feeding. The bowl-shape model-hole distributed with airflow holes was introduced, and the main structural parameters were determined. The mechanical models of seed filling and seed feeding process were established. The effects of airflow hole's diameter, number of airflow holes and rotational speed on seeding performance were investigated and the adaptability of pneumatic cylinder-type centralized seed-metering device for hybrid rice varieties was analyzed. The results showed that: The orders of affecting factors were the number of airflow holes, and the airflow hole diameter and rotational speed. When the rotational speed of 20 r/min, the number of the air holes of 7 and airflow hole's diameter of 1. 7 mm, and the qualified rate, miss-seeding rate, reseeding rate and cavity rate were 93. 33%, 2. 50%, 4. 17%, and 0. 58%, respectively. The apiece row consistency variation coefficient of seeding quantity was 2. 08%. Furthermore, the qualified rate was 90%, and the missing rate and multiple rate were no more than 6. 00% and 5. 00%, respectively. The seed breakage rates were less than 0. 20%, and the apiece row consistency variation coefficient of seeding quantity was less than 3. 00% for three hybrid rice varieties including Tianyouhuazhan, Fanyou 609, which indicated that the seed metering device had good seeding adaptability to different hybrid rice varieties. The field experiment of the pneumatic cylinder-type centralized seed-metering device was conducted. It was found the average seeds per hill were 3. 56, the qualified seeding rate and the average distance were respectively 89. 33% and 190. 3 mm, which met the requirements of precision hill seeding. This research provided the basis for the structural design of centralized and precision hill direct-seeding for rice.