Abstract: In view of the difficulty, high cost, and low efficiency of Medicago falcata L. harvesting on a large scale, this paper presents a walking, selfpropelled Medicago falcata L. harvester design that can realize the harvesting and collection of Medicago falcata L. The overall structure of the machine was introduced, and the key components such as cutting device, collecting device, and transmission device were designed. The designed blade pitch was 34 mm, the stroke of a single moving blade was 17 mm, the cutting power consumption was 1.175 kW, the fan power consumption was 0.124 3 kW, the main air duct size was 30-50 mm, the branch pipe was 15-25 mm, and the motor power was 2.2 kW. In order to test the performance of the machine, field operation tests were carried out based on response surface analysis method. The results showed that the optimal operation parameters of the machine were: working speed 0.72 m/s, cutting speed 0.78 m/s, conveying speed 1.29 m/s, working efficiency of the harvester 0.091 2 hm2/ h, and the rate of missed cutting was 1.75%. The factor contribution rate of each factor to work efficiency was blowing speed>cutting speed>operation speed. The factor contribution rate of each factor to missed cutting rate was cutting speed>operation speed>blowing speed. All indexes meet the design requirements and can realize stable and efficient operation.

Key words:  Medicago falcata L. harvester, key components, response surface analysis, parameter optimization

摘要： 针对黄花苜蓿收割难度大、成本高、效率低制约其大规模推广的问题,设计一种能实现黄花苜蓿收割与收集的手扶电动式收获机。介绍该机的整体结构并对切割装置、收集装置和传动装置等关键部件进行参数设计,设计刀片节距为34 mm,单个动刀的行程17 mm,切割功耗为1.175 kW,风机功率消耗为0.124 3 kW,主风管尺寸为30～50 mm,支分管为15～25 mm,选用电机功率为2.2 kW;为测试该机作业性能,基于响应面分析法进行田间作业试验,结果表明,该机的最佳作业参数为:作业速度0.72 m/s,切割速度0.78 m/s,吹送速度1.29 m/s,此时收获机工作效率为0.091 2 hm~2/h,漏割率为1.75%;各因素对工作效率的因子贡献率为:吹送速度>切割速度>作业速度;各因素对漏割率的因子贡献率为:切割速度>作业速度>吹送速度。各项指标均达到设计要求,能实现稳定高效作业。

关键词: 黄花苜蓿收获机, 关键部件, 响应面分析, 参数优化