【作者】 李正琦；

【导师】 李明辉；

【作者基本信息】 陕西科技大学 ， 机械电子工程， 2012， 硕士

【摘要】 全电动注塑机是工业和民用产品的重要机械装备，其复杂的动力学响应分析以及疲劳寿命预估是注塑装备向大型、高速方向发展所面临的重大课题。由于工作环境以及复杂多变的工况条件，导致全电动注塑机在工作过程中易产生复杂多变的动态冲击，这些动态冲击载荷最终将导致全电动注塑机系统关键零部件以及整机钢结构产生疲劳破坏，而且业界普遍反映合模机构故障率比较高，因此，研究全电动注塑机合模机构并预估其关键部件疲劳寿命对全电动注塑机的日常维修和维护具有非常重要的意义。为解决全电动注塑机动态冲击响应分析及合模机构关键部件疲劳寿命预估问题，本文针对大型全电动注塑机，综合机械、材料、力学等相关理论，以计算机仿真为手段，对全电动注塑机合模机构关键部件进行了结构优化研究和疲劳寿命预估，本文包括以下主要研究内容：（1）．由于载荷传递经过的结构和部件将承受着更大的周期性动载荷的冲击作用，更易产生疲劳破坏，因此，对模具部分关键零部件结构的工作特性进行了研究。基于力学的相关理论，采用有限元分析方法分别建立零部件有限元模型，并分析其典型工况下的静力学特性及其应力响应规律，在危险节点处获得应力响应曲线和数据，为全电动注塑机疲劳寿命做出贡献，也为寿命预估提供数据。（2）．本文针对关电动注塑机合模机构关键部件，如拉杆，减速箱，前支座以及整机等做了基于ANSYS-WORKBENCH的静力学分析，特别是对前支座，在静力学分析的基础上对两种设计进行静力学分析，得出较好设计方案，之后又对较好设计方案进行拓扑优化设计，再进行静力学分析，与优化前进行对比，使应变和变形都大幅减小。（3）．为全电动注塑机整体的疲劳寿命预估做前期准备，基于雨流计数法分析和处理危险节点处的应力响应曲线，得到其幅值-频次直方图，对拉杆进行寿命预估，再结合零部件的P-S-N曲线，利用Miner线性累积疲劳损伤理论，后续完成对全电动注塑机整体的疲劳寿命预估。本文对全电动注塑机合模机构关键零部件结构优化及疲劳寿命的研究，对全电动注塑机的维护和保养具有一定的指导意义，其动态响应分析思想及疲劳寿命预估方法亦可推广到其他机械的研究中。更多还原

【Abstract】 All-electric Injection Molding Machine is the main equipment of portoperation, and its complex dynamic response analysis and system reliabilityevaluation are major issues that the All-electric Injection Molding Machine facesin the development of large and high-speed. Due to its complex workingcondition, the All-electric injection molding machine sustains lots of complexdynamic impacts which will eventually cause the key parts and steel structure toemerge fatigue damage. So development on the law of the key parts’ stressdistribution and its fatigue life makes significant importance for the All-electricInjection Molding Machine.To solve the problem of the dynamic impulse response analysis and fatiguelife prediction about All-electric Injection Molding Machine, the papercomprehensives machinery, materials,mechanical and other related theories, thendo work characteristics and fatigue life prediction base on computersimulation.The main content includes as follows:Firstly,due to the parts on the route of the load bear complex impact of thedynamic load, so they are more likely to emerge fatigue flaw and damage,therefore, we take a research on working characteristic of the key parts and thesteel structure base on the related theory of mechanic.Use the finite elementanalysis method to analyze its typical operating conditions of the staticmechanical properties and take transient dynamic analysis to obtain thedangerous test points’ fatigue stress response curve. This is the precondition toestimate the machine’s lifetime.Secondly, based on the ANSYS software, the paper does static analysis on the key components of the electric injection molding machines, such as rod,speed changing box, front support and overall unit, etc. Especially on the frontsupport, we come to better design between two ideas, then do topologyoptimization design on it, it is good to meet system performance requirements.Thirdly, the paper introduces the related theory of the fatigue briefly.According to machine’s fatigue stress response curve, the paper takes advantageof Miner fatigue accumulating theory to estimate the fatigue life of theAll-electric injection molding machine.In the paper, the research on the working characteristic of the mouldsystem’s key parts and steel structure and the estimation of the All-electricinjection molding machine’ fatigue life will take some guiding significance in themaintenance of the machines, and its dynamic response analysis ideas andpredition method of fatigue life can be applied to other lifting machinery orconstruction machinery.更多还原