Authors

Abstract

In response to the demands of farmland operations in hilly and mountainous areas of China, a direct connection four-wheel drive micro-tiller transmission system is designed, aiming to enhance the transmission efficiency and reliability. Based on the agronomic requirements and the functional demands of the gears, a scheme combining gear transmission and chain transmission are adopted to achieve the coordinated control of the walking part and the rotary tillage part, supporting five working modes including fast tillage, slow tillage and reverse gear. By optimizing the gear parameters and structural layout, we select 20CrMnTi material and carbon-nitrogen co-permeation treatment process, which ensure the load-bearing capacity and compactness of the gears. The gear strength, shaft fatigue safety factor and bearing life are verified by combining KissSoft and Romax software. The results show that the safety factors of the gear tooth surface and tooth root are both higher than the target values, the shaft and bearing life meet the design requirement of 1000 hours, and the transmission efficiency simulation reaches 92.2%, which is superior to the efficiency of the traditional pulley transmission system. Field experiments show that when the micro-tiller has a forward speed of 3.46 km/h and a ploughing depth of 22.93 cm, the soil fragmentation rate is 78.58%, the ploughing depth stability coefficient is 90.20%, and the performance meets the requirements of national standards. This research can provide technical references for the transmission system design of small agricultural machinery in hilly and mountainous areas.

Abstract in Chinese

针对中国丘陵山区耕地作业需求，本文设计了一种直联式四驱微耕机传动系统，旨在提升传动效率与可靠性。基于农艺要求与挡位功能需求，采用齿轮传动与链传动结合的方案，实现行走部分与旋耕部分的协同控制，支持快耕、慢耕、倒挡等5种工作模式。通过优化齿轮参数与结构布局，选用20CrMnTi材料及碳氮共渗处理工艺，确保齿轮承载能力与紧凑性。结合KissSoft与Romax软件对齿轮强度、轴疲劳安全系数及轴承寿命进行校核，结果表明：齿轮齿面与齿根安全系数均高于目标值，轴与轴承寿命满足1000小时设计要求，传动效率仿真达92.2%，优于传统皮带轮传动系统效率。田间试验表明，微耕机前进速度3.46 km/h、耕深22.93 cm时，碎土率78.58%，耕深稳定性系数90.20%，性能符合国家标准要求。该研究可为丘陵山区小型农机的传动系统设计提供技术参考。