甘蔗切断机构负载敏感系统液压冲击的仿真及试验研究

Simulation and Experimental Study on Hydraulic Impact of Load-Sensitive System of Sugarcane Cutting Mechanism

针对甘蔗收获机在丘陵地区作业时液压冲击导致的管路破损和泄漏等问题,以输出功率最大的切段机构液压系统为研究对象,运用AMESim仿真软件建立切断机构液压负载敏感系统仿真模型,研究负载敏感阀的启闭时间、负载敏感泵出口至负载敏感阀的供油管路长度以及负载敏感系统的反馈管路长度对系统压力冲击的影响规律。仿真结果表明:缩短换向阀的开启时间、延长换向阀的关闭时间可有效降低系统的液压冲击,缩短泵出口管路长度、延长泵阀反馈管路长度可有效减缓系统的液压冲击现象。通过试验获得了与仿真结果基本一致的结论:当换向阀开启和关闭的响应时间分别为产品样本给定参数的最小值和最大值时,液压冲击幅度分别降低13.6%和33.1%;泵出口至敏感阀的管路长度每缩短0.5 m,系统冲击降低幅度约为0.5 MPa;反馈管道长度每延长0.5 m,系统压力冲击下降约0.808 MPa。

Aiming at the problems of pipeline damage and leakage caused by hydraulic impact of sugarcane harvester operating in hilly areas,taking the hydraulic system of the cutting mechanism with the largest output power as the research object,AMESim simulation software was used to establish a simulation model of the hydraulic load sensitive system of the cutting mechanism.The influences of the opening and closing time of the load-sensitive valve,the length of the oil supply pipeline from the load-sensitive pump outlet to the load-sensitive valve,and the feedback pipeline length of the sensitive pump valve on the pressure impact of the system were studied.The simulation results show that shortening the opening time of the reversing valve and extending the closing time of the reversing valve can effectively reduce the hydraulic impact of the system,shortening the length of the pump outlet pipeline and extending the length of the pump valve feedback pipeline can effectively slow down the hydraulic impact of the system.The conclusions obtained by experiment are basically consistent with the simulation results:when the response time of the reversing valve opening and closing is the minimum and maximum values of the product sample parameters respectively,the hydraulic impact amplitude is reduced by 13.6% and 33.1% respectively;for every 0.5 m reduction in the length of the pipeline from the pump outlet to the sensitive valve,the system impact is reduced by about 0.5 MPa;for each 0.5 m extension of the feedback pipeline length,the system pressure shock drops by about 0.808 MPa.