电容器盖板自动预压机及其控制系统设计

针对电容器盖板预压工序存在自动化程度低、劳动强度大等不足,设计了电容器盖板自动预压机及其控制系统.对电容器盖板自动预压机的机械系统进行了详细设计,包括铝壳放置转盘组件、电容器定位组件、盖板预压组件、电容器推出组件、电容器接收组件等;采用可编程序逻辑控制器(programmable logic controller,PLC)作为控制系统的主控制器,实现多种规格电容器盖板的自动预压;依据电容器高度的不同,通过图形操作终端(graphic operating terminal,GOT)设置和调整生产参数.该设备已投入实际生产使用,运行结果表明:整机性能稳定,实际运行状况良好,满足了生产线高柔性化、高效率、高质量的自动化加工要求.     

铝电解电容器芯包引脚刺孔机控制系统设计

针对目前铝电解电容器芯包引脚刺孔中存在的自动化程度低、劳动强度大等不足,设计了铝电解电容器芯包引脚刺孔机控制系统,并提供了电气硬件和软件系统设计方案.该系统以三菱FGA系列PLC为核心,结合步进电机、振动盘、气缸以及光纤传感器和位置传感器等元件的检测定位,实现华司自动上料、芯包移动、引脚刺孔、芯包翻转等工序的自动连续运行.现场调试运行表明:该系统运行可靠平稳,操作简单,劳动强度低,能够满足生产线高效率、高质量的自动化加工要求.     

电容器铝壳自动上料-定量灌胶控制系统设计

针对电容器铝壳自动上料和定量灌胶工序存在自动化程度低、灌胶精度低等问题,设计了电容器铝壳自动上料-定量灌胶控制系统.采用三菱FX3GA系列PLC对控制系统的软硬件进行合理配置,并详细设计了系统的硬件组成和软件流程;采用三菱GS系列触摸屏,实现系统的参数修改和状态监测功能.该系统已在电容器生产企业实际应用,应用效果表明:系统运行可靠、平稳,运行周期为10s,铝壳定量灌胶误差小于2%,其提高了产品质量和生产效率,满足企业生产要求,具有一定的推广价值.     

Comparative study of Li[Ni1/3Co1/3Mn1/3]O2 cathode material synthesized via different synthetic routes for asymmetric electrochemical capacitor applications

Layered Li[Ni_1/3Co_1/3Mn_1/3]O₂ cathode materials were synthesized by different synthesis routes using carbonate and hydroxide co-precipitation methods. Physical properties of the prepared Li[Ni_1/3Co_1/3Mn_1/3]O₂ varied depending on the synthesis method employed. These materials were applied as a positive electrode to an asymmetric electrochemical capacitor with activated carbon as the negative electrode and the electrochemical properties of the capacitor were studied. Li[Ni_1/3Co_1/3Mn_1/3]O₂ prepared by the carbonate co-precipitation exhibited higher capacitance and better rate capability with stable cycling retention over 500 cycles than Li[Ni_1/3Co_1/3Mn_1/3]O₂ prepared by the hydroxide co-precipitation. The asymmetric electrochemical capacitor (AEC) cell (AC/Li[Ni_1/3Co_1/3Mn_1/3]O₂) had a voltage slope from 0.2 to 2.2 V and delivered a capacity of 60 F g⁻¹ with a capacity retention of 88.4% during 500 cycles based on the overall active materials weight. The leakage current was largely decreased for the asymmetric electrochemical capacitor and the maintained voltage was 84.4% during 3 days.     

一种应用于AC PDP的反gamma校正与动态对比度增强相结合的新方法

由于交流等离子体显示器(AC PDP)的显示特性是线性的,因此在显示接收到的视频信号前必须要进行反gamma校正.同时,为了提高显示器件的画质,必须要进行对比度增强.直方图均衡化是一种重要的对比度增强方法,但直方图均衡化的增强效果不可控,往往由于过增强而导致图像失真.本文结合上述两种技术提出了一种应用于AC PDP的反gamma校正与可控的动态对比度增强相结合算法.该算法能够在对输入视频图像进行反gamma校正的同时,实现幅度可调的动态对比度增强.同时避免了传统直方图均衡化对图像产生的过增强现象.本文实现了基于提出算法的实时图像处理器,并且在50英寸AC PDP上进行了测试.模拟仿真及实际测试结果均表明,本文提出的算法能够使AC PDP的画质得到显著提升.     

激光跟踪仪两级双轴联动闭环控制系统研究

为保证激光跟踪仪的跟踪精度,设计选择了两级双轴联动控制系统,以直流力矩电机作为第1级控制,为粗调机构;音圈电机作为第2级,为精调机构;并将此2个电机安装于垂直和水平2个方向实现三维空间的跟踪,偏差信号经过PI调节后,生成双极性PWM控制执行机构完成闭环控制。通过这种控制方式,达到了激光跟踪仪的精度要求。     

Reliability with finite buffer size for a multistate manufacturing system with parallel production lines

Abstract

This study examines system reliability for a manufacturing system with parallel production lines by creating a model of a multistate manufacturing system (MMS). System reliability is defined as the probability of demand satisfaction, which reflects the probability that the current capacity state of the MMS can successfully process a given demand. In particular, a buffer station with a finite size is taken into consideration to avoid blockage and starvation in the MMS. To the best of our knowledge, there is no existing research that considers a finite buffer size in a model of an MMS with parallel production lines. This study proceeds through the following phases. (i) In the model construction phase, the amount of input material, workload, and minimal capacity required by each workstation to satisfy a given demand level are studied by flow analysis; subsequently, a buffer usage matrix (BUM) is proposed to calculate buffer reliability. (ii) In the performance evaluation phase, system reliabilities with both infinite and finite buffer sizes are derived in terms of both minimal capacity vector and buffer reliability. (iii) In the case demonstration phase, two examples are utilized to illustrate the proposed method. Results of both examples show that the system reliability is overestimated with an infinite buffer size.     

Optimal economic production quantity policy for a parallel system with repair,rework, free-repair warranty and maintenance

Hot standby redundancy maintains the working order of a system, repairs offer restoration in case of failure, and preventive maintenance (PM) prevents trouble. Warranties provide assurance to customers, and a superior warranty signifies higher product quality. The running costs of redundancy, maintenance and warranties influence decisions during product manufacture. Therefore, this paper presents an economic production quantity (EPQ) model for a parallel system with maintenance, production, and free-repair warranty (FRW) programmes. The production system begins with a basic unit and produces conforming items. PM is performed after the production run period and is classified as imperfect or perfect. If the basic unit fails, it is repaired and returned to operation after perfect PM; the spare unit is online only during the repair time of the basic unit. The spare will produce some number of defective goods, which are reworked in the same inventory cycle. The hot spare is minimally repaired if it fails in its standby or online mode. In this study, an inferior item is defined as one that satisfies specifications on inspection and is usable but is likely to incur postsale servicing costs when sold under an FRW. The total cost of this EPQ model includes setup, holding, PM, restoration, minimal repair, and warranty costs. The optimal production runtime is determined by minimising the total cost. Several cases are discussed in this paper, and the proposed model is illustrated using a numerical example and sensitivity.