中型液压挖掘机工作装置机液联合仿真分析及阀体优化研究

发布时间：2018-04-14 01:21

本文选题：挖掘机 + 液压系统　；参考：《吉林大学》2013年硕士论文

【摘要】：挖掘机作为一种工程机械，在工业与民用建筑中广泛使用，液压挖掘机凭借其性能、指标上的优越性也得到迅速发展。液压挖掘机工作装置的性能决定着挖掘效率和可靠性，而多路阀性能好坏决定着液压系统的稳定性，因此工作装置的结构、液压系统及多路阀的不断改进和创新是液压挖掘机进一步发展的关键。对于挖掘机工作装置的研究，本论文主要从两方面进行分析：一方面是工作装置的运动分析；另一方面是工作装置的液压系统分析。论文以某公司的20吨级液压挖掘机为研究对象，利用LMS Virtual.lab Motion仿真软件对挖掘机进行整机的动力学仿真，利用AMESim仿真软件对该型号的挖掘机进行液压系统的建模、仿真，并利用这两个软件进行机液联合仿真，做出简单的系统分析，并用试验进行相关数据的验证；最后对于阀体的结构提出了几点改进优化方案。本论文主要研究内容如下： 1.阐述本课题研究的背景和意义，，分别介绍了液压挖掘机国内外研究现状和发展趋势，液压挖掘机液压技术和仿真技术的国内外发展现状。 2.对工作装置进行理论分析和运动学仿真分析。首先，利用D-H坐标系理论分析挖掘机工作装置的运动位姿空间；其次，在CATIA中建立整机三维模型，导入LMSVirtual.lab Motion中，并对模型适当简化后，建立挖掘机整机动力学模型，进行挖掘机工作装置的挖掘包络线模拟。 3.对工作装置的液压系统进行理论分析和仿真分析。首先将挖掘机工作装置单独的液压回路原理进行介绍，再利用AMESim软件建立多路阀及上车工作装置液压系统的模型，并进行简单的液压系统仿真分析。 4.对工作装置进行机液联合仿真分析。在AMESim和LMS Virtual.lab Motion之间设置好接口，进行机械系统和液压系统的联合仿真，模拟挖掘机的真实作业过程，使仿真数据更加接近试验数据，为进一步的试验分析提供依据。 5.对挖掘机的工作过程进行试验研究，测量工作装置的压力、流量、油缸位移等相关数据。一方面进行空载单动作的试验测量，每个单动作在两个不同转速下重复几次试验，用来计算出工作装置的油缸摩擦力；另一方面测量复合动作，模拟空载挖掘全过程。最后分析工作装置单动作和复合动作的实验数据，并与仿真数据进行对比。 6.对阀体的结构提出了两点改进方案：一是从增大流量的观点出发，提出了增加进出油口通道来增大流量；另一方向是从控制部分着手，以跟随原理的理念设计主阀杆的跟随运动，也相当于一个闭环控制，以此来降低液动力对阀芯的扰动，最终实现对阀杆运动的精确控制。
[Abstract]:As a kind of construction machinery, excavator is widely used in industrial and civil buildings. Hydraulic excavator has been developed rapidly by virtue of its performance.The performance of the working device of hydraulic excavator determines the efficiency and reliability of excavating, and the performance of multi-way valve determines the stability of hydraulic system, so the structure of the working device,The improvement and innovation of hydraulic system and multi-way valve are the key to the further development of hydraulic excavator.For the research of excavator working device, this paper mainly analyzes from two aspects: on the one hand, motion analysis of the working device; on the other hand, the hydraulic system analysis of the working device.This paper takes the 20-ton hydraulic excavator of a company as the research object, uses the LMS Virtual.lab Motion simulation software to carry on the dynamics simulation to the excavator, uses the AMESim simulation software to carry on the modeling and the simulation to the hydraulic system of the excavator.The two softwares are used to simulate the mechanical and hydraulic system to make simple system analysis and test to verify the relevant data. Finally, several improved optimization schemes for the structure of the valve body are proposed.The main contents of this thesis are as follows:1.This paper expounds the background and significance of this research, introduces the research status and development trend of hydraulic excavator at home and abroad, and the development status of hydraulic technology and simulation technology of hydraulic excavator at home and abroad.2.Theoretical analysis and kinematics simulation analysis of the working device are carried out.Firstly, using D-H coordinate system theory to analyze the motion position and pose space of excavator's working device; secondly, establishing the whole machine's three-dimensional model in CATIA, importing it into LMSVirtual.lab Motion, and establishing the excavator's whole machine dynamic model after the model is simplified properly.The excavation envelope line simulation of excavator working device is carried out.3.The hydraulic system of the working device is analyzed theoretically and simulated.Firstly, the principle of hydraulic circuit of excavator working device is introduced, and then the hydraulic system model of multi-way valve and boarding working device is established by using AMESim software, and a simple simulation analysis of hydraulic system is carried out.4.The machine-liquid joint simulation analysis is carried out on the working device.The interface between AMESim and LMS Virtual.lab Motion is set up, the joint simulation of mechanical system and hydraulic system is carried out, the real operation process of excavator is simulated, and the simulation data are closer to the test data, which provides the basis for further test analysis.5.The working process of the excavator is studied experimentally, and the pressure, flow rate and displacement of the cylinder are measured.On the one hand, the experimental measurement of no-load single action is carried out, each single action is repeated several times at two different rotational speeds to calculate the friction force of the cylinder of the working device; on the other hand, the composite action is measured to simulate the whole process of no-load excavation.Finally, the experimental data of single action and compound action of the working device are analyzed and compared with the simulation data.6.Two improvements to the structure of the valve body are put forward: one is to increase the flow rate from the point of view of increasing the flow rate, and the other is to increase the flow rate by increasing the inlet and outlet passage, and the other direction is to start from the control part.The following motion of the main stem is designed according to the principle of follow, which is equivalent to a closed loop control, so as to reduce the disturbance of the hydraulic force to the valve core and to realize the accurate control of the stem motion.
【学位授予单位】：吉林大学
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：TU621

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