牵引式打药机精准喷洒系统的设计与试验

Design and Test of Precision Spraying System of Tractive Drug Dispenser

为减少农药对环境的污染,实现精准施肥,设计了一种高效、精准、简便的电控精准喷洒系统,并将其应用于牵引式打药机。基于PLC控制技术建立由数据设定、数据传输、流量控制、数据采集、上传计算、对比分析等组成的闭环控制系统,由PLC输出控制信号,控制电磁比例阀、电磁压力调节阀的开度,实现系统流量、压力调控。以牵引式喷药机行走速度、系统压力、设定单位面积施药量为试验因素,以单位面积施药量与设定值偏差量、喷头最大的喷雾量变异系数为试验指标进行正交试验,确定试验参数较优组合。结果显示:牵引式喷药机行走速度为7km/h,系统正常工作压力为1.0MPa,单位面积施药量为50L/667m2时,单位面积施药量与设定值偏差量小于3%、喷头最大的喷雾量变异系数小于10%。由此表明,系统具有良好的稳定性与精准的控制性,满足市场使用要求,符合国家检验标准,具有推广价值。

In order to reduce the pollution of pesticides to the environment and achieve precise fertilization,an efficient,precise and simple electronically controlled precise spraying system is designed and applied to the trailed sprayer.Based on the PLC controller,a closed-loop control system consisting of data setting,data transmission,flow control,data ac-quisition,upload calculation,and comparative analysis is established.PLC outputs control signal to control the opening of electromagnetic proportional valve and electromagnetic pressure regulating valve to realize system flow and pressure reg-ulation.The field test of the prototype machine takes the walking speed of the traction sprayer,the system pressure,and the set spraying rate per unit area as the test factors,and the deviation between the spraying rate per unit area and the set value and the coefficient of variation of the maximum spray rate of the nozzle are used as the test indicators.Orthogonal test to determine the optimal combination of test parameters.The test results show that when the walking speed of the traction sprayer is 7km/h,the normal working pressure of the system is 1.0MPa,and the spraying rate per unit area is 50L/mu,the deviation between the spraying rate per unit area and the set value is less than 3%,and the spray head The maximum spray volume coefficient of variation is less than 10%.The results show that the system has good stability and precise controllability.It meets the requirements of market use,conforms to national inspection standards,and has social promotion.