基于Pro/E的机械零部件三维动态序列装配技术研究

三维动态序列装配技术在机械产品和工程设计行业的设计、制造、检测、展示、学习、资金节约、功效提高等方面具有非常重要的意义,其制作具有一定的技术复杂性和技巧性,目前许多三维CAD软件有此功能,但很少有此方面的具体介绍,为了给机械及工程技术人员提供一些有益的借鉴,以某高楼外墙清洗机吸盘部件三维动态序列装配动画的制作为例,针对Pro/E三维机械设计软件的动态序列装配技术进行了详细介绍,给出了整个制作流程。     

转移印刷应用于大批量微型电子器件并行装配的研究

转移印刷是一种新技术,它能将大量高性能半导体器件并行装配到几乎所有的基材上,包括玻璃、塑料、金属或其他半导体材料。这种半导体转印技术利用弹性移印头从源硅片有选择性地拾取器件,然后将这些器件印刷到目标基材上。其关键技术是调整弹性移印头与半导体器件的黏附能力。转移过程是大批量并行的,可一次转印成千上万个器件。研究结果表明,99.9%以上的此类产品是可以通过转印实现的。此外,印刷芯片的放置精度小于±5μm。     

钱潮轴承新增圆柱滚子轴承装配连线

近日，钱潮轴承新建的圆柱滚子轴承装配连线顺利竣工投产，初步实现了装配自动化生产，大大提高了该类产品的生产效益。钱潮轴承从两年前开始进行圆柱滚子轴承产品的研制生产，现已形成120万套/年的生产能力，研制成功的58种型号的圆柱滚子轴承已成为新的销售增长点。随着生产规模的不断扩大，原来手工装配的工艺不仅出错机率高，而且在人工搬运过程中也容易出现磕碰伤。要进一步提高产品装配质量和生产效率，建设一条高自动化的轴承装配线势在必行。圆柱滚子轴承装配连线的竣工投产，加快了该产品最后一道工序——装配的生产流转速度，目前该连线仅需1名生产工人即可完成日班产2000套，相当于4-5名操作工人1天的班产产量，为公司带来了巨大的生产效益。     

摩托车单向器自动装配机气动系统设计

针对当前摩托车单向器组件主要采用手工装配、装配效率低、随机性大、无法对装配过程实现有效管理控制的情况,为了易于对零件装配过程进行实时监测和提高生产效率,开发了一种智能摩托车单向器自动装配机。介绍了摩托车单向器自动装配机的上料系统、装配系统、检测系统和落料系统的机械结构,重点阐述了设备的气动系统设计,并进行了实验研究。结果表明,该设备可实现组成单向器的5种零件自动上料和装配,同时降低了操作人员的劳动强度,生产效率提高约50%。其气动系统噪音小、工作可靠,可应用于摩托车单向器的大批量生产。研究结果可为其他相似异形零件自动装配机的开发提供参考。     

电液执行器装配调试问题及解决方案

文章介绍具有ESD功能的开关型电液执行器国内外发展状况,并对其工作原理进行了简单描述,同时针对电液执行器的组件查验、装配及试验调试整个过程,一一列举因尺寸、错位、喷漆、深孔、交叉孔毛刺等原因导致的质量不合格,装配时尺寸超差或连接不通畅问题,以及所引起的无法安装,试验调试时触发灵敏度不高使得行程不够等问题。开展了相关的工艺改进和提升工作,提供了成熟的工艺解决方案,为日后更好的安装和调试打下了好的基础。     

基于NX参数化自顶向下的设计方法及其在减速器中的应用

介绍了自顶向下的设计方法,并且在NX中利用自顶向下的方法对减速器进行了设计,将自顶向下方法和NX参数化相结合,通过建立减速器的控制结构,实现了减速器的整体结构控制;利用NX的wave功能和"表达式"功能实现了参数的逐级传递、各零件参数之间的关联、零部件的并行设计和自动化装配。     

分组装配法及其必要和充分条件的探讨

本文给出了包含有一级子装配的分组装配法的分析和计算方法;提出了满足分组装配的必要和充分条件并进行了详细的分析,同时也给出了为满足这些条件应采取的具体措施。     

基于Syncrofit的航天器全三维装配设计方法研究

<正>航天器装配对产品制造的开发周期、产品质量、经济效益等具有十分重要的影响。随着计算机和网络技术的飞速发展,产品装配设计方法从二维图纸逐渐向三维数字化模型过渡。近年来,国外以波音、空客等飞机研发公司在10余年内研发的新型产品为代表,集中体现了国外数字化装配技术的应用现状和发展方向,如在B787的装配设计过程中采用基于Syncrofit的三维装配设计     

汽车驾驶室总成电器检测系统

针对汽车驾驶室装配过程中存在的电器故障点无法检测的问题,采用PLC与上位计算机联控的方式设计一套电器检测系统,实现驾驶室电器元件故障点的检测以及检测信息的存储、查询、报表生成及打印输出。     

基于压缩感知产品内部装配正确性检测的研究

针对工厂一般采用批量产品的抽检对产品内部结构进行检验,由于受人为因素的影响很容易造成漏判和误判,提出了将压缩感知理论应用到产品内部装配正确性的检测。首先通过比较选用了具有优势的K-SVD算法来构造稀疏基矩阵,在解决稀疏解时采用了运算复杂度较低的贪婪算法,通过验证选取了具有优势的正交匹配追踪(OMP)进行分类。实验结果表明,随着训练样本数量的增加正确识别率在增加但是以时间的增加为代价,在保证识别率的前提下采用了PCA降维,可有效节约时间为4.41S,提高了识别速度。     

Best-matching protocols for assembly in e-work networks

Assembly networks pose many challenges to the comprising businesses due to their ever-growing distributed nature. This article explores the benefits of incorporating best-matching protocols (BMP) into the principles of design for assembly (DFA) to make better use of already existing information on equipment, parts and suppliers. Best-matching protocols for cooperation requirement planning (BMP-CRP), for part matching (BMP-part) and supplier selection were developed. A case study for the matching of parts and suppliers is provided. The results of the case study corroborate the benefits in quality and costs that the best-matching protocols can yield for businesses in an assembly e-work network.     

流水工序调度与生产效率的关系模型分析

提出一种基于粒子群算法的流水工序调度任务优化模型。利用流水工序调度任务的特点得到流水工序时间约束条件,利用粒子群算法的原理建立流水工序调度任务优化模型,利用粒子群算法对模型进行求解。仿真实验表明,利用该算法能够得到流水工序调度问题的最优解,提高生产效率。     

Optimally locating in-house logistics areas to facilitate JIT-supply of mixed-model assembly lines

In modern-day production systems, ever-rising product variety poses a great challenge for the internal logistics systems used to feed mixed-model assembly lines with the required parts. As an answer to this challenge many manufacturers especially from automobile industries have identified the supermarket-concept as a promising part feeding strategy to enable flexible small-lot deliveries at low cost. In this context, supermarkets are decentralized in-house logistics areas in the direct vicinity of the final assembly line, which serve as intermediary stores for parts. Small tow trains are loaded with material in a supermarket and deliver parts Just-in-Time to the stations lying on their fixed route. This paper discusses the general pros and cons of the supermarket-concept and treats the decision problem of determining the optimal number and placement of supermarkets on the shop floor. A mathematical model is proposed, an exact dynamic programming algorithm presented, and the validity of the proposed approach for practical purposes as well as the trade-off resulting from fixed installation and maintenance cost is investigated in a comprehensive computational study.     

Ant colony optimization for the single model U-type assembly line balancing problem

An assembly line is a production line in which units move continuously through a sequence of stations. The assembly line balancing problem is defined as the allocation of tasks to an ordered sequence of stations subject to precedence constraints with the objective of optimizing a performance measure. In this paper, we propose ant colony algorithms to solve the single-model U-type assembly line balancing problem. We conduct an extensive experimental study in which the performance of the proposed algorithm is compared against best known algorithms reported in the literature. The results indicate that the proposed algorithms display very competitive performance against them.     

A comparison of product costing practices in discrete-part and assembly manufacturing and continuous production process manufacturing

Research into product costing practice has not studied whether there are differences in product costing practice between different types of manufacturing. This paper compares the product costing practices of operating units in discrete-part and assembly manufacturing, and continuous production process manufacturing. The results show that there are few differences in product costing practices between these two manufacturing methods. Similar proportions of operating units in these two manufacturing environments use similar methods to treat overheads and have similar experiences of activity-based costing. The only area of difference is in the use of overhead rates where significantly more units in discrete-part and assembly manufacturing use a direct labour hour rate and significantly more units in continuous production process manufacturing use units produced and production time-based rates.     

A comparison of search techniques for minimizing assembly time in printed wiring assembly

In the robotics assembly of DPP model, the coordinates of assembly point and magazine are dynamically changed during robotics assembly so that evaluation of the assembly efficiency is extremely complicated. To route the robotics travel, most related investigations have utilized the fixed coordinate of insertion points and magazine using the Traveling Salesman Problems (TSP) method to sequence the insertion points after arbitrarily assigning the magazine. However, robotics travel routing should be based on a relative coordinate to obtain a better solution because the robotics, board and magazine are simultaneously moved at different speeds during assembly. To resolve such a dynamically combinatorial problem, this study presents the Genetic Algorithm (GA), Simulated Annealing (SA), and Tabu Search (TS) based algorithms. These approaches can simultaneously arrange the insertion sequence and assign the magazine slots by the computer and yield a better performance compared to the conventional approach. Results presented herein also demonstrate that the larger the number of insertion points and/or part numbers the better the performance. These approaches are also compared.     

Cycles of production: from assembly lines to cells to assembly lines in the Volvo Cab Plant

This paper analyses changes in work organisation at the Volvo Cab Plant in Umeå, Sweden in order to identify those contingent elements that impact upon the choices made in selecting specific production technologies. It suggests that managerial decision making is not necessarily located within rational or business enhancement paradigms.     

Analytical analysis of a generic assembly system

The assembly of components is a key element in manufacturing facilities. Nevertheless, literature analyzing the dynamic behavior remains scarce. The paper narrows this gap by studying a generic first-come first-serve assembly system, consisting of two generally distributed component input streams. The field of probability theory serves as a means to derive good approximations for the waiting time of the components to form a kit and the inter-arrival time of the kits at the assembly station. Apart from providing insight in generally accepted managerial principles, this analysis also constitutes a required step in obtaining the performance of an open queuing network including assemblies.     

Job rotation in assembly lines employing disabled workers

In this paper we consider the programming of job rotation in the assembly line worker assignment and balancing problem. The motivation for this study comes from the designing of assembly lines in sheltered work centers for the disabled, where workers have different task execution times. In this context, the well-known training aspects associated with job rotation are particularly desired. We propose a metric along with a mixed integer linear model and a heuristic decomposition method to solve this new job rotation problem. Computational results show the efficacy of the proposed heuristics.