Authors

Abstract

To reduce miss-seeding and improve the stability of single-clove pickup in garlic seed metering devices, a spoon-clamp type garlic seed metering device was designed. The proposed mechanism combined spoon-type seed pickup with spring-assisted clamping, so garlic cloves with irregular surfaces could be picked up, carried, cleaned, and discharged more stably. Based on the geometric characteristics of three garlic varieties, the key parameters of the seed plate, seed pickup spoon, and opening-closing mechanism were determined by theoretical analysis. A three-dimensional model of the seed metering device and garlic-clove models were established using the discrete element method. Single-factor simulations were then performed to analyze the effects of seed plate speed and seed pickup spoon diameter on the qualified seeding index, reseeding index, and miss-seeding index. The suitable simulated operating range was 1–7 r/min for seed plate speed and 25–35 mm for seed pickup spoon diameter. Bench tests showed that the suitable parameter combination for “Acheng Purple Garlic” and “Nong’an Purple Garlic” was a seed plate speed of 4 r/min and a seed pickup spoon diameter of 32 mm. For “Zhaozhou White Garlic”, the suitable combination was 5.5 r/min and 28 mm. These results showed that the spoon-clamp mechanism was feasible for improving single-clove garlic metering stability under controlled bench-test conditions.

Abstract in Chinese

针对大蒜蒜瓣形状不规则导致排种器漏播率高、单粒取种稳定性不足等问题，本文设计了一种勺夹式大蒜排种器。该装置将取种勺取种与弹簧辅助夹持相结合，使蒜瓣在取种、携种、清种和投种过程中保持较稳定的约束状态。基于三种大蒜蒜瓣的几何特性，通过理论分析确定排种盘、取种勺及开合机构等关键参数。采用离散元法建立排种器三维模型和蒜瓣颗粒模型，并通过单因素仿真分析排种盘转速和取种勺直径对合格指数、重播指数和漏播指数的影响。仿真结果表明，排种盘转速为1–7 r/min、取种勺直径为25–35 mm时排种性能较优。台架试验结果表明，“阿城紫皮蒜”和“农安紫皮蒜”的适宜参数组合为排种盘转速4 r/min、取种勺直径32 mm；“肇州白皮蒜”的适宜参数组合为排种盘转速5.5 r/min、取种勺直径28 mm。研究结果说明，勺夹式取种机构在受控台架条件下具有提高大蒜单粒取种稳定性的可行性。