摘 要

全自动液压精冲机在工业生产中起着越来越重要的作用，随着汽车、航天、冶金化工、武器装备的不断发展，人们对于精冲机的性能要求越来越高特别是对其吨位、精冲精度、冲裁速度等方面。本文主要针对于大吨位、高精度的快速精冲机的快速缸和主缸液压系统进行研究，其对于以后如何设计精冲机的液压系统和提高精冲机的性能具有一定的指导意义。本文主要进行了以下研究工作并得到了如下结论：

（1）根据全自动液压精冲机的工作性能要求，完成了快速缸的液压系统设计，包括负载计算、油量需求计算、关键元器件选型及快速缸液压系统原理图的设计。

（2）分别建立了皮囊蓄能器、二通方向插装阀、阀控非对称缸的数学模型，采用Matlab/Simulink分别对这三个关键液压部件进行了仿真分析，分析了不同种工况下对各自性能的影响。研究表明：蓄能气充气压力最佳为13MPa，其上升时间为0.005s，其响应速度较快且系统震荡较小。二通插装阀的仿真显示系统压力为12-13MPa时，插装阀的响应品质及响应速度最佳。阀控非对称缸的模型中得到系统的相角裕度P_m = 3.4939度，幅值裕度G_m =97.7542db，满足阀控缸系统稳定性条件。

（3）建立了快速缸液压系统的仿真模型，分析了蓄能器体积、预充气压力及负载的变化对快速缸液压系统性能的影响。研究表明：当蓄能器体积过小如8L会使快速缸的加速度急剧上升，位移误差增大。基于系统性能和经济性考虑蓄能器体积最佳选为16L。改变蓄能器预充气压力只会影响整个系统上升时间，预充气压力越接近系统工作压力，上升时间就越短。增加负载会增大快速缸的位移误差，在正常的负载质量变化范围内（11130-13130kg），该液压系统能满足设计要求。

（4）介绍了主缸液压系统的特点，依据其液压原理图完成了主缸液压系统的建模与仿真。研究表明：在PID优化控制下，主缸的最大位移误差可以控制在0.4mm内，小于设计允许误差（0-0.7mm）。

本文的研究工作对于大吨位液压精冲机液压系统的设计有一定的指导意义，能够为我国制造大型液压精冲机提供技术支持。

关键词：精冲机、液压系统设计、数学模型、仿真分析

Abstract

With the continuous development of the automotive, aerospace, metallurgy, transportation, automatic hydraulic fine blanking are playing an increasingly important role in industrial production, and more and more demand on fine blanking performance is put forward, such as fine blanking precision, punching speed, working tonnage and so on. This article focuses on research of the large tonnage, high-precision fine blanking fast cylinder and the master cylinder hydraulic system, which has some significance for how to design of the hydraulic system of fine blanking and improve fine blanking performance in the future.

1. according to the performance requirements of automatic hydraulic fine blanking, this paper completes the design of fast cylinders hydraulic system, including load calculations, oil demand computing, key components selection and the fast cylinder hydraulic system schematic design.

(2) Mathematical models of the accumulator, two-way cartridge valve, valve controlled asymmetrical cylinder are established in this paper, and three key components hydraulic models are simulated in Matlab / Simulink for the analysis on the components performance in different kinds of working conditions. The research shows: the optimal precharge pressure gas accumulator is 13MPa. Under this condition, its rise time is 0.005s, and it contributes to this system faster response and less vibration. Simulation shows that the system pressure of two-way cartridge valve stays for 12-13 MPa, its response quality and speed is best. Obtained in valve controlled asymmetric cylinder model, the phase margin P_m is 3.4939 degrees and the amplitude margin G_m is 97.7542db, which meet the valve controlling cylinder system stability conditions.

(3) Based on AMEsim software platform, the rapid cylinder hydraulic system simulation model is established. Then, this paper analyses effect on the system characteristics when the accumulator volume, precharge pressure and load change. The result shows:1)When the accumulator volume is too small, such as 8L, it would increase the acceleration and displacement error sharply. Consider the system performance and economy, the accumulator volume selected as 16L is the best. 2) Changing the accumulator precharge pressure will affect the system rise time. The closer the pre-charge pressure system to working pressure, the shorter the rise time. 3)Increasing the load will contribute the fast cylinder displacement error. the hydraulic system could meet the design requirements when the load mass varies from 11130kg to 13130kg.

(4)The characteristics of the master cylinder hydraulic system is introduced. In accordance with hydraulic schematic diagram,the modeling and simulation of the master cylinder hydraulic

system are completed in this paper. Studies have shown that: with PID optimization control, the maximum displacement error of the master cylinder can be controlled within 0.4mm, less than the design tolerance (0-0.6mm).

The thesis shows guiding significance for the large-tonnage hydraulic fine blanking hydraulic system design, and provides the technical supports for the actual manufacture.

Keywords: Fine blanking machine, hydraulic system design, the mathematical model, simulation analysis.

目录

摘 要 I

Abstract II

目录 1

第1章 绪论 3

1.1 引言 3

1.2国内外发展现状 3

1.3液压系统的发展趋势 3

1.4液压系统建模理论 4

1.5主要内容及拟采用的技术方案及措施 5

第2章 液压精冲机快速缸液压系统设计 6

2.1全自动液压精冲机的介绍 6

2.2精冲机快速缸液压系统的设计 7

2.2.1快速缸系统的技术参数 7

2.2.2快速缸的负载分析 7

2.2.3初选快速缸的工作压力 8

2.2.4液压缸的尺寸计算 9

2.2.5系统工作压力的核算 9

2.2.6快速缸的行程设计 10

2.2.7液压缸的油量计算 10

2.3关键元器件的选型 12

2.3.1液压泵流量计算和选型 12

2.3.2蓄能器的选型 12

2.4液压管道尺寸确定 12

2.5液压油的选择 13

2.6蓄能器数学模型的建立 13

2.6.1蓄能器数学模型的建立 13

2.6.1蓄能器模型仿真 16

2.7二通插装阀的建模与仿真 19

2.7.1二通插装阀的介绍 19

2.8.2二通方向控制插装阀数学模型的建立 21

2.8.3插装阀模型的仿真 24

2.8阀控非对称液压缸系统建模与仿真 26

2.8.1调速回路的介绍 26

2.8.2阀控非对称液压缸数学模型的建立 27

2.8.3阀控非对称液压缸系统仿真 31

2.9本章小结 33

第3章 基于AMEsim软件下快速缸系统建模 34

3.1 AMESim软件概述 34

3.1.1 AMESim软件的组成 34

3.1.2AMESim软件的HCD库 35

3.1.3AMEsim建模过程 35

3.2快速缸系统的液压原理图 35

3.3快速缸系统的液压仿真模型的搭建 36

3.3.1参数处理及设置 37

3.4仿真结果分析 38

3.4.1快速缸的性能分析 39

3.4.2蓄能器的性能分析 41

3.5关键元器件参数对系统性能的影响 43

3.5.1蓄能器体积对快速缸运动性能的影响 43

3.5.2初始充气压力对快速缸运动性能的影响 47

3.4.3负载对系统性能的影响 49

3.6本章小结 53