Structural Scheme Optimization Design for the Stationary Platen of a Precision Plastic Injection Molding Machine

The current development of precision plastic injection molding machines mainly focuses on how to save material and improve precision, but the two aims contradict each other. For a clamp unit, clamping precision improving depends on the design quality of the stationary platen. Compared with the parametric design of stationary platen, structural scheme design could obtain the optimization model with double objectives and multi-constraints. In this paper, a SE-160 precision plastic injection molding machine with 1600 kN clamping force is selected as the subject in the case study. During the motion of mold closing and opening, the stationary platen of SE-160 is subjected to a cyclic loading, which would cause the fatigue rupture of the tie bars in periodically long term operations. In order to reduce the deflection of the stationary platen, the FEA method is introduced to optimize the structure of the stationary platen. Firstly, an optimal topology model is established by variable density method. Then, structural topology optimizations of the stationary platen are done with the removable material from 50%, 60% to 70%. Secondly, the other two recommended optimization schemes are given and compared with the original structure. The result of performances comparison shows that the scheme II of the platen is the best one. By choosing the best alternative, the volume and the local maximal stress of the platen could be decreased, corresponding to cost-saving material and better mechanical properties. This paper proposes a structural optimization design scheme, which can save the material as well as improve the clamping precision of the precision plastic injection molding machine.

IMPROVE THE KINETIC PERFORMANCE OF THE PUMP CONTROLLED CLAMPING UNIT IN PLASTIC INJECTION MOLDING MACHINE WITH ADAPTIVE CONTROL STRATEGY

The kinetic characteristics of the clamping unit of plastic injection molding machine that is controlled by close loop with newly developed double speed variable pump unit are investigated. Considering the wide variation of the cylinder equivalent mass caused by the transmission ratio of clamping unit and the severe instantaneous impact force acted on the cylinder during the mold closing and opening process, an adaptive control principle of parameter and structure is proposed to improve its kinetic performance. The adaptive correlation between the acceleration feedback gain and the variable mass is derived. The pressure differential feedback is introduced to improve the dynamic performance in the case of small inertia and heavy impact load. The adaptation of sum pressure to load is used to reduce the energy loss of the system. The research results are verified by the simulation and experiment, The investigation method and the conclusions are also suitable for the differential cylinder system controlled by the traditional servo pump unit.

Hydraulic cylinder control of injection molding machine based on differential evolution fractional order PID

Injection molding machine,hydraulic elevator,speed actuators belong to variable speed pump control cylinder system.Because variable speed pump control cylinder system is a nonlinear hydraulic system,it has some problems such as response lag and poor steady-state accuracy.To solve these problems,for the hydraulic cylinder of injection molding machine driven by the servo motor,a fractional order proportion-integration-diferentiation(FOPID)control strategy is proposed to realize the speed tracking control.Combined with the adaptive differential evolution algorithm,FOPID control strategy is used to determine the parameters of controller on line based on the test on the servo-motor-driven gear-pump-controlled hydraulic cylinder injection molding machine.Then the slef-adaptive differential evolution fractional order PID controller(SADE-FOPID)model of variable speed pump-controlled hydraulic cylinder is established in the test system with simulated loading.The simulation results show that compared with the classical PID control,the FOPID has better steady-state accuracy and fast response when the control parameters are optimized by the adaptive differential evolution algorithm.Experimental results show that SADE-FOPID control strategy is effective and feasible,and has good anti-load disturbance performance.

Kansei Engineering Applied to the Form Design of Injection Molding Machines

This study investigated the relationship between a subject’s evaluation of injection molding machines (IMMs) and formal design features using Kansei engineering. This investigation used 12 word pairs to evaluate the IMM configurations and employed the semantic differential method to explore the perception of 60 interviewees of 12 examples. The relationship between product feature design and corresponding words was derived by multiple regression analysis. Factor analysis reveals that the 12 examples can be categorized as two styles—advanced style and succinct style. For the advanced style, an IMM should use a rectangular form for the clamping-unit cover and a full-cover for the injection-unit. For the succinct style, the IMM configuration should use a beveled form for the safety cover and a vertical rectangular form for the clamping-unit cover. Quantitative data and suggested guidelines for the relationship between design features and interviewee evaluations are useful to product designers when formulating design strategies.

Model evolvement and reuse technology of injection molding machine based on performance knowledge

To illuminate the necessity of model evolvement and reuse, dynamics of injection molding machine＇s product models are analyzed. The performance knowledge is used to support the model evolvement and reuse. The driven factors of mechanical product model are concluded. The dynamic characteristics of reuse. Finally, HT1800X1N series injection molding machines are taken as examples to illuminate that the arithmetic is correct and practical.

基于UG和Moldflow的塑料外壳注塑模具设计与数控加工

以某塑料外壳为例,采用Moldflow软件进行注塑成型分析,得到了优化的浇注系统和冷却系统,并对塑件翘曲变形进行比较分析,获得了最优工艺参数。应用UG Moldwizard模块进行注塑模设计,并利用UG CAM模块对模具型腔进行数控加工工艺分析、生成刀路轨迹仿真并进行联机加工。该方法实现了模具CAD/CAE/CAM的一体化设计,缩短了开发周期,改善了塑件质量,对指导企业生产有一定的实用价值。

基于UG和MoldFlow的卷发机外壳注塑模设计与数控加工

采用MoldFlow软件对卷发机外壳注塑模进行工艺分析,得到最佳浇口位置及最佳工艺参数,并运用UG Mold-Wizard模块设计其注塑模。利用UG/CAM模块分析该模具型腔的数控加工工艺,生成刀具加工轨迹并进行加工过程仿真,生成数控程序,从而实现了模具设计与制造的一体化。

基于MoldFlow的洗衣机上面板浇注系统优化设计

以洗衣机上面板为研究对象,结合塑件和模具结构特点,建立了2种不同的顺序针阀式热流道转冷流道潜入式进浇浇注方案,并运用MoldFlow进行了注射成型模拟分析,通过分析结果确定了最终的浇注系统方案.经试模生产,塑件质量良好,表明采用MoldFlow技术能有效改善塑件成型质量,提高生产效率.

Model predictive control of servo motor driven constant pump hydraulic system in injection molding process based on neurodynamic optimization

In view of the high energy consumption and low response speed of the traditional hydraulic system for an injection molding machine,a servo motor driven constant pump hydraulic system is designed for a precision injection molding process,which uses a servo motor,a constant pump,and a pressure sensor,instead of a common motor,a constant pump,a pressure proportion valve,and a flow proportion valve.A model predictive control strategy based on neurodynamic optimization is proposed to control this new hydraulic system in the injection molding process.Simulation results showed that this control method has good control precision and quick response.

基于STM32的动态注塑信号调节器设计

文中设计了一种基于STM32芯片与UCOSIII操作系统的动态注塑信号调节器。采用DDS芯片AD9833与数字电位器MCP41010配合实现了P/Q信号的发生与调幅;采用运算放大器OP07组成的加法器实现P/Q振动信号与P/Q静态信号的合成;基于RS485接口与Modbus通讯协议实现动态注塑信号调节器与上位机的实时通讯;基于emWin图形库设计了人机交互界面,可以在触摸屏上设定选定注塑参数。试验测试表明:动态注塑信号调节器能够根据上位机反馈的通讯信息在不同工序下输出不同波形、频率与幅值的P/Q动态注塑信号,满足泵控液压激振系统与动态注塑的应用需求。

安装扭矩对抱箍式锁模力仪测试结果影响的研究

注塑机锁模力监测系统主要用于在三板式注塑机中对锁模力的实时监测,以控制产品质量和防止设备的损坏。其中抱箍安装方式的锁模力实时监测仪由于价格低,安装可靠性高等特点,被广泛采用。在实际使用中,抱箍式注塑机锁模力传感器信号的准确度,在一定范围内与所施加的抱紧力(安装扭矩)有一定相关性,对后期维护会有较大影响。对抱箍式传感器在使用中的受力情况进行了分析,根据硅胶需要满足和格林柱之间无滑移的测试条件,分析了硅胶上的拉伸摩擦力以及正压力必须满足的条件,并根据传感器头的安装结构,推导了满足硅胶受力条件时,抱箍收紧时所需的理论最小扭矩公式,最后基于自行研发的抱箍式注塑机锁模力监测仪,进行了实验。实验结果表明,在扭矩较小时(100%理论最小扭矩),抱紧力的大小对测试结果影响很大;当抱紧力达到一定阶段后(150%最小理论扭矩),测试结果趋于稳定;当抱紧力达到一定值后(≥200%最小扭矩),测试结果的精度基本不再变化。

基于贝叶斯优化机器学习的多尺度注塑质量预测

注塑质量受到注塑成型过程中多类工艺特征影响,实际生产中采集的特征数据存在时间尺度不同、粒度不统一的问题。对此,提出基于贝叶斯优化机器学习的多尺度注塑质量预测方法。针对注塑生产过程中不同尺度的生产特征进行特征提取,运用机器学习对注塑件的质量进行预测。对注塑数据进行预处理,运用注意力机制门控循环单元提取时序特征,统一注塑机状态数据与注塑过程高频采样数据粒度。特征融合后,使用贝叶斯优化随机森林模型与轻量级梯度提升机模型进行训练与测试。试验表明,对比传统统计值提取特征方法,注意力机制门控循环单元时序提取后的预测效果更好。与普通机器学习相比,贝叶斯优化随机森林模型与轻量级梯度提升机模型预测精度更高。

参数快速自适应的电动注塑机的期望补偿自适应鲁棒控制

为了提高电动注塑机模具控制精度和稳定性,首先,针对由齿轮和滚珠丝杆结构组成的模具控制部分,建立了非线性动态模型。随后,提出了一种期望补偿自适应鲁棒控制器(desire compensate adaptive robust control,DCARC)。将参数估计过程和鲁棒控制律的设计分开,以提供更好的参数估计,并引入基于随机梯度下降法的模型补偿项以确保其瞬态性能,实现对其高精度的控制,并同时具备对参数的快速自适应能力。最后,设计了与传统控制器的对比实验,并在电动注塑机上进行了实验。对比实验结果验证了提出的方法具有较高的跟踪性能和较强的参数自适应性。

超声塑化微注射成型技术研究现状及展望

简述了超声塑化中界面摩擦生热、黏弹性生热和空化效应3种生热机理及其研究现状,从超声塑化微注射成型(UPMIM)工艺参数的影响效果和成品性能的影响因素两个角度分析概括了UPMIM工艺的研究现状。介绍了现有UPMIM装置的结构及加工步骤,概括了UPMIM在精密药物输送装置、智能定制植入物和微流控设备等领域的应用研究现状,指出了UPMIM技术大规模工业化生产应用所具有的技术优势和面临的诸多技术挑战,对UPMIM未来的主要研究方向与应用领域进行了总结与展望。

基于模糊解耦策略的小型注塑机料筒温度F-PI复合控制器

在塑料产品的生产过程中,注塑机料筒温度的响应速度和稳定性对最终塑料产品的质量具有重要影响。为了提高小型注塑机料筒温度的控制精度,针对料筒具有的惯性大、非线性、大滞后、强耦合等温度特性,在模糊控制不能满足控制要求的背景下,提出了基于相邻加热段之间温差的模糊解耦策略,通过利用相邻加热段之间的温差信息,建立模糊解耦控制器,对各段料筒之间的温度耦合进行解耦控制。实验结果表明,该控制方法效果良好,达到目标温度所用时间为1092 s,最大超调量只有3%,但稳态性能较差。为解决稳态性能较差的问题,在模糊解耦的基础上建立F-PI复合控制器,通过引入积分环节消除系统在稳态下的偏差。在Matlab/Simulink环境下进行仿真并在注塑机上进行验证,结果表明,F-PI复合控制方法不仅具有良好的动态响应,还具有更高的稳态精度,稳态偏差仅为±1℃。因此基于模糊解耦策略的F-PI复合控制方法不仅能对料筒的温度耦合进行解耦控制,还有效提高了系统的稳定性和控制精度,具有良好的鲁棒性。

基于机器学习与遗传算法的注塑产品工艺参数优化

注塑成型工艺可以高效成型高精度产品,被广泛使用。通过优化注塑产品工艺参数,可以获得更高的表面质量和尺寸精度。为了获得最佳工艺参数组合,设计了基于关键工艺参数组合的极端梯度提升决策树模型。为了解决训练数据不平衡问题,引入尺寸加权修正方法,提高对不合格产品尺寸的预测精度。使用遗传算法对改进极端梯度提升决策树模型以产品尺寸误差最小为目标进行全局寻优,得到最佳工艺参数组合。最佳工艺参数组合为模腔压力39.4 bar、切换压力33.8 bar、射嘴压力49.4 bar、回水温度72.6℃、模温机水流量58.7 cm^(3)/s。

注塑机模板的热-结构耦合仿真及拓扑优化

为了提高注塑制品的质量和降低注塑机制造成本,以1600 kN双曲肘注塑机的定模板和动模板为研究对象,采用传热学理论和有限元仿真分析,运用ANSYS对定模板和动模板进行了系统的热-结构耦合计算,分析了模板的温度场和热-结构耦合的影响。在此基础上运用拓扑优化方法对模板进行了轻量化设计,优化后模板的总变形量有所增加。动模板应力增加了9.94 MPa,定模板应力增加了10.27 MPa,但均在工程许用范围内,合模机构质量相较原始模型减轻了10.5%。

卧式液压注塑机结构模块化研究与设计

以朗亿LYH680注塑机为例,对其结构和功能进行分析,多角度进行可拆卸评价。将注塑机的总体功能分解成多个功能单元,并从使用者的角度对各单元实施相关性评价,建立相应的相关性矩阵。基于制造、装配与功能3个方面确定各自的权重值,代入总体相关性矩阵;引入截矩阵,以不同阈值为划分标准,实施划分方案比较;依据比较结果及设备实际情况得到功能模块划分方案。通过对注塑机零部件的划分,建立了注塑机模块化设计的方案,增加了注塑机各零部件的通用性,从而有效提升设计、生产效率,促进产品的新技术更新。

注塑模具高效加工应用研究

注塑模具产品广泛应用于汽车、家电、 3C、玩具、航空航天等日常生产生活中。产品更新换代的周期越来越短。这就迫使产品设计者及生产厂家需要快速适应时代快速发展的节奏。为了提高加工效率,必须研究注塑模具高效加工创新工艺。此次生产实践证明采用深切削,高转速,快进给的方法,以及结合优化好的程序上机加工,可以有效提高加工效率30%以上。可为企业高效生产注塑模模具提供技术参考,为竞赛及培训提供借鉴参考作用。

Micro-optical fabrication by ultraprecision diamond machining and precision molding

Ultraprecision diamond machining and high volume molding for affordable high precision high performance optical elements are becoming a viable process in optical industry for low cost high quality microoptical component manufacturing. In this process, first high precision microoptical molds are fabricated using ultraprecision single point diamond machining followed by high volume production methods such as compression or injection molding. In the last two decades, there have been steady improvements in ultraprecision machine design and performance, particularly with the introduction of both slow tool and fast tool servo. Today optical molds, including freeform surfaces and microlens arrays, are routinely diamond machined to final finish without post machining polishing. For consumers, compression mold- ing or injection molding provide efficient and high quality optics at extremely low cost. In this paper, first ultrapreci- sion machine design and machining processes such as slow tool and fast too servo are described then both compression molding and injection molding of polymer optics are discussed. To implement precision optical manufacturing by molding, numerical modeling can be included in the future as a critical part of the manufacturing process to ensure high product quality.