215Hp平地机前轮负载敏感液压辅助驱动系统研究

发布时间：2019-05-20 13:28

【摘要】：前轮驱动技术是现代平地机提高牵引性能的重要手段之一,通过充分利用前轮附着质量,可以提高整机的有效牵引力,从而提高平地机的作业效率,扩大平地机的使用范围,尤其是矿区等对大型平地机有需求的特殊场合。目前对平地机前轮驱动技术的综合性研究依然存在局限性,因此,围绕着系统方案设计、参数匹配、同步控制及效率提升等关键问题展开系统性研究,对大型平地机的设计与开发具有重要的理论与实际意义。本文以215Hp液力式平地机为研究对象,对前轮驱动行驶系统进行了研究与设计。通过对三种不同前轮驱动方案的比较分析,以及对开中心与闭中心负载敏感系统的效率分析,提出了基于闭中心负载敏感变量泵的前轮行驶液压驱动系统方案,通过应用负载敏感变量泵、负载敏感多路阀及自由轮状态阀等关键技术,解决了前后驱动轮同步、前驱左右轮同步及前驱不工作时动力脱开等问题;根据215Hp平地机整机参数,确定了前轮运动学和动力学关键参数,完成了液压系统静态参数匹配计算及液压泵和液压马达等关键元件的选型和校核,并对全轮驱动的平地机牵引特性进行了计算;基于AMESim仿真软件,对平地机前轮负载敏感液压驱动系统进行了建模和仿真,建立了负载敏感变量泵和负载敏感多路阀等模型,分析了系统在不同工况下的动态响应、偏载工况下左右轮的同步性能以及系统在不同工况下的能耗和效率,对比研究了开中心与闭中心负载敏感系统的工作效率,仿真结果验证了系统的可行性。
[Abstract]:The front wheel drive technology is one of the important means to improve the traction performance of the modern grader. By making full use of the attachment quality of the front wheel, the effective traction force of the whole machine can be improved, thus the working efficiency of the grader can be improved and the application range of the grader can be expanded. Especially in mining areas and other special occasions where there is a demand for large graders. At present, there are still limitations in the comprehensive research on the front wheel drive technology of grader. Therefore, the key problems such as system scheme design, parameter matching, synchronous control and efficiency improvement are systematically studied. It is of great theoretical and practical significance to the design and development of large grader. In this paper, the front wheel drive driving system is studied and designed with 215Hp hydraulic grader as the research object. Based on the comparative analysis of three different front wheel drive schemes and the efficiency analysis of open center and closed center load sensitive system, a hydraulic drive system scheme of front wheel driving based on closed center load sensitive variable pump is proposed. Through the application of key technologies such as load sensitive variable pump, load sensitive multi-way valve and free wheel state valve, the problems of front and rear drive wheel synchronization, front drive left and right wheel synchronization and power release when the front drive is not working are solved. According to the parameters of 215Hp grader, the key parameters of front wheel kinematics and dynamics are determined, and the static parameter matching calculation of hydraulic system and the selection and check of key components such as hydraulic pump and hydraulic motor are completed. The traction characteristics of the all-wheel drive grader are calculated. Based on AMESim simulation software, the load sensitive hydraulic drive system of grader front wheel is modeled and simulated, and the load sensitive variable pump and load sensitive multi-way valve are established, and the dynamic response of the system under different working conditions is analyzed. The synchronization performance of the left and right wheels under the partial load condition and the energy consumption and efficiency of the system under different working conditions are compared and studied, and the working efficiency of the open center and closed center load sensitive systems is compared and studied. The simulation results verify the feasibility of the system.
【学位授予单位】：长安大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TH137

【引证文献】