水稻直播机组合型孔排种器设计与试验

Design and Experiment of Combined Hole-type Metering Device of Rice Hill-drop Drilling Machine

摘要:

为同时满足常规稻与杂交稻的播种要求以及实现对播量的快速调节，以型孔轮式排种器为基础，设计了一种由型孔轮壳、型孔轮和调节机构组成的组合型孔排种器。以瓢形孔为组合型孔设计的基础，型孔轮壳上有多个带引种槽的瓢形通孔，可与型孔轮上的大、小型孔对应组合成完整的型孔，调节机构起调节定位作用。以常规稻秀水134和玉香油占以及杂交稻花优14和培杂泰丰为试验材料，对型孔的形状、尺寸和形式以及调节机构进行了设计与试验。通过调节机构的可靠性试验得出，调节机构的可靠性合格，且可5s内实现播量快速调节。根据已有的理论和模型，计算确定了型孔数量为8个，型孔大端半径为5mm，小端半径为4.5mm，长度为11mm。通过理论计算和三因素两水平试验的结果表明：引种槽的长度为6.5mm，倒角为60°，型孔轮上大型孔的形式为深度6.5mm柱形型孔，小型孔的形式为深度4mm的勺形型孔时试验效果最佳，在转速50r/min 时播秀水134品种，小型孔的穴粒数合格率达87%，大型孔的穴粒数合格率达87.67%，且变异系数分别为22.60%和20.46%，满足播种要求。相关性分析进一步验证了型孔形式是影响穴粒数合格率的关键，引种槽的长度和倒角对穴粒数合格率与变异系数均有影响。播种适应性试验结果表明，组合型孔排种器能同时满足常规稻（秀水134、玉香油占）与杂交稻（花优14、培杂泰丰）的播量要求，变异系数较小，具有较好的适应性。

关键词:水稻; 排种器; 组合型孔; 引种槽; 播量可调

Abstract:

Due to the differences of soil, climate, varieties in different regions and different planting habits, the rice planting agronomic requirements are different. In order to meet the seeding requirement of conventional rice and hybrid rice simultaneously and to adjust the seeding rate quickly, a combined holetype metering device was designed based on a simple holetype metering device which was developed by South China Agricultural University. The device included holetype shell, holetype roller and adjusting mechanism. A complete holetype was comprised by the label through holes which were uniformly distributed on the holetype shell and the small/big holetype which were uniformly distributed on holetype roller. The shape, size and style of the holetype and the adjusting mechanism were designed and optimized. The reliability experiments of the adjusting mechanism were carried out and the result showed that its structure was reasonable and the seeding rate adjusting process could be completed in 5 s. According to the existed model and theory, the outline dimensions of the holetype were calculated and the results confirmed that the number of the holetype was 8, the big radius was 5mm, the small radius was 4.5mm and the length was 11mm. To further study on the main impact factors of the seeding performance of the metering device, the length and the chamfering angle of the guiding groove and the type of the holetype were selected as the factors of the performance experiment while the conventional rice pregerminated seed Yuxiangyouzhan was selected as the experimental material. The results indicated that the optimal combination parameters were the length of the guiding groove of 6.5mm, the chamfering angle of 60°, the big holetype on the holetype roller with 6.5mm cylindrical hole and the small holetype with 4mm spoonshaped hole. The test results with rotational speed of 50r/min showed that the qualified rate of the seed number per hole of the small holetype was 87%, the seeding qualified rate of the big holetype was 8767%, and the seeding variable coefficients of these towed holetype were 2260% and 2046% which could meet the rice seeding requirement. The correlation analysis showed that the main effect on the qualified rate was the type of the holetype, and the length and the chamfering angle of the guiding groove had effects on the seeding variable coefficients as well. Furthermore, the adaptability experiment was designed by 4 varieties pregerminated rice seeds and 4 rotational speeds (30r/min, 40r/min, 50r/min and 60r/min). The results showed that the combined holetype metering device had good adaptability of seeding conventional rice seeds such as Xiushui 134 and Yuxiangyouzhan, and hybrid rice seeds such as Huayou 14 and Peizataifeng.

Key words:rice; metering device; combined holetype; guiding groove; adjusting seeding rate