面向多品种变批量的可重构制造系统的设计方法研究

可重构制造系统的设计目标是要确定各种零件的生产周期、各种零件之间的生产顺序与加工各种零件所用的组态。建立了各生产周期成本模型、重构成本模型与全生产周期成本模型。由各种零件的批量确定加工各种零件的标准生产周期，分析系统成本冗余，得到了多组偏差生产周期，求出了各种生产周期下各种零件之间所有生产排序的K-优组态路径。通过比较所求得的组态路径，可以获得一条最优与多条次优组态路径。用案例验证了所提出的方法。     

挤压成形技术在接插件端子模具设计中的应用

详细分析了接插件端子零件冷挤压成形工艺方案，拟定了接插件零件的工艺参数，采用冷挤压成形技术，完成了接插件冷挤压成型机的系统组成、模具结构及其关键技术等设计。采用冷挤压成形技术研制设计的DC型接插件端子自动挤压成形机，不仅能实现送料、成形、切断的连续自动完成，结构小巧、合理，大大提高了接插件的生产效率和材料利用率，降低了制造成本，保证了冷挤压接插件的成型质量，而且使接插件端子的硬度和强度得到加强。     

差速器行星齿轮冷挤压工艺及制造研究

结合开发差速器行星齿轮冷挤加工,根据该零件的技术要求,依据冷挤压理论,分析研究了该零件的冷挤压工艺及制造方案,特别对冷挤压工艺中的几个主要问题进行了研究.通过研究得到,冷挤压加工是该齿轮最合适的生产方式,它具有以下独特优势:降低生产成本,提高原材料利用率,提高齿轮质量,提高生产效率,降低环境污染,有利于可持续发展,是值得推广的低碳锥齿轮加工技术.     

假捻盘冷挤压成形模具的优化

分析了原假捻盘冷挤压成形工艺方案，针对原冷挤压零件存在的表面缺陷，提出了优化冷挤压成形模具结构的措施，大大提高了模具使用寿命，保证制造出了合格的零件。     

面向复杂零件网络化制造的资源优化配置方法

为实现复杂零件网络化制造的资源优化配置,提出一种以零件工艺流程为核心的制造资源优化配置方法。该方法依据零件工艺流程,设计逻辑制造单元和逻辑加工路线,进行基于逻辑制造单元和逻辑加工路线的制造任务分解和描述。为了对逻辑加工路线配置最优的可执行加工路线,以运行成本、时间和加工质量为目标,建立多目标优化模型;在用遗传算法求解模型的过程中,每一代种群,基于影响度因子将运行成本、时间和加工质量的目标特征值矩阵转换为相对隶属度矩阵,进而以每个染色体的距优海明加权距离平方与距劣海明加权距离平方之和最小为准则,求取基于相对隶属度的适应度值。最后,以具体实例证明了该方法解决复杂零件网络化制造资源优化配置问题的可行性与有效性。     

一种新型接插件挤压成形机的设计

针对中小企业的实际情况,采用冷挤压成形制造技术,研制开发自动化程序高的接插件挤压加工设备,实现送料、成形、切断的连续自动完成,大大提高了生产效率和材料的利用率,降低了制造成本,确保接插件零件的质量稳定可靠。     

超大截面变化台阶轴复合成形与计算机数值模拟

分析一种应用在新能源汽车启动电动机上的超大截面变化的多台阶轴类零件的结构特点,以及其冷挤压成形工艺技术的技术难点,详细论述此类零件复合冷挤压成形的工艺流程、成形坯件和冷挤压模具的设计要点,设计出预制坯、预镦坯、以及冷挤压三道工序的冷挤压复合成形模具,并通过三维有限元数值模拟技术对其复合冷挤压成形工艺进行模拟和分析,针对性地对预制坯以及冷挤压的凹模入模角、过渡圆角、工作带等模具结构和尺寸参数进行优化与改进,并进行深入的试验研究,成形加工出的零件完全满足后续机械加工对其结构和尺寸的要求,解决了此类零件成形制坯困难的问题,达到大幅度降低生产加工的成本和节能环保的目的,为下一步大批量产业化生产打下良好的基础。     

冷挤压工艺在电器工程零件制造中的应用

介绍了一种冷挤压工艺在有色金属零件制造中的应用,它与传统的冷挤压工艺是在一个封闭的型腔中完成金属材料的成型。该方法也可以应用到一般金属零件的加工和小型复杂零件的加工中。     

冷挤压技术在汽车转向器上的应用

相比传统机加工方式，冷挤压工艺可以节约材料、降低成本和改善性能。随着国内冷挤压技术的不断提高，在汽车转向器零部件的制造中逐渐开始应用。本文结合转向器中的齿轮、齿条、阀芯、阀套和横拉杆等主要零件，对冷挤压工艺的实际使用情况进行了介绍和阐述。     

管类零件冷挤压成型的工艺与装备设计

管类零件采用冷挤压工艺制造,可节省材料,与切削工艺相比可提高生产率约30倍。该文介绍了冷挤压工艺分析、冷挤压模具、液压原理及专用冷挤压机的设计要点。     

Multiple-Objective Scheduling for the Hierarchical Control of Flexible Manufacturing Systems

This paper presents a hierarchical approach to scheduling flexible manufacturing systems (FMSs) that pursues multiple performance objectives and considers the process flexibility of incorporating alternative process plans and resources for the required operations. The scheduling problem is solved at two levels: the shop level and the manufacturing system level. The shop level controller employs a combined priority index developed in this research to rank shop production orders in meeting multiple scheduling objectives. To overcome dimensional complexity and keep a low level of work-in-process inventory, the shop controller first selects up to three production orders with the highest ranking as candidates and generates all possible release sequences for them, with or without multitasking. These sequences are conveyed to the manufacturing system controller, who then performs detailed scheduling of the machines in the FMS using a fixed priority heuristic for routing parts of multiple types while considering alternative process plans and resources for the operations. The FMS controller provides feedback to the shop controller with a set of suggested detailed schedules and projected order completion times. On receiving these results, the shop controller further evaluates each candidate schedule using a multiple-objective function and selects the best schedule for execution. This allows multiple performance objectives of an FMS to be achieved by the integrated hierarchical scheduling approach.     

资源约束下拆卸线平衡问题的建模与改进混合蛙跳算法

针对实际拆卸线中涉及的资源约束和危害零件问题,以资源总数、工作站数和危害指数为目标函数,构建了多目标资源约束拆卸线平衡问题数学模型。基于AND/OR关系,在优先关系矩阵中添加OR关系的描述,解决了产生初始解仅考虑AND关系的不足问题。提出了一种融入Pareto思想的改进混合蛙跳算法  ,该算法采用基于满意度的改进排序分组策略来解决多目标优化种群分组问题;提出了一种新的交叉变异方式进行局部搜索以提高收敛性能;利用拥挤距离机制评价非劣解集以及有效地维护外部档案容量。采用田口实验和统计分析方法确定了算法最佳参数组合,将改进前后的混合蛙跳算法及NSGA-Ⅱ对测试算例的求解结果进行了多指标对比分析,研究结果表明：改进混合蛙跳算法具有良好的综合求解优势。最后,将所提算法应用到某电冰箱的资源约束拆卸线平衡问题中,为决策者提供了较优的拆卸方案。     

齿轮箱设计制造中的成本控制

齿轮箱是机械工业中广泛应用的传动设备,是由箱体、传动件、外购件、标准件、小件以及其他配套件构成.成本控制是关系到企业效益的关键因素之一.齿轮箱生产的成本主要包括各材料成本和各零部件加工成本.     

Rapid manufacturing techniques in the development of an axial blood pump impeller

This paper presents a comparison of manufacturing techniques used in the development of an axial blood pump impeller. In this development process the impeller was designed and its performance was evaluated with the aid of computational fluid dynamics (CFD). Prototypes of those designs where the CFD results show promise were needed in sufficient quantities at a low cost for experimental validation of the CFD results. As the impeller is less than 16 mm in diameter with a maximum blade thickness of about 1.5 mm, innovative manufacturing techniques are explored in this paper to determine the best process for quick fabrication of prototypes that are dimensionally accurate, structurally robust and low in cost. Four rapid prototyping techniques were explored. The completed parts were compared on the basis of manufacturing time, quality and strength of parts obtained, manufacturing cost and also in vitro performances. Based on these studies, it was concluded that selective laser sintering (SLS) is the most appropriate method for the quick production of prototype parts for evaluation of pump performance.     

Analysis of priority mix planning for the fabrication of semiconductors under uncertainty

Because of intensive capital investment in semiconductor manufacturing, the priority mix decision plays a critical role for effective administration. The potential value of products, efficiency in the deployment of equipment, and characteristics of cash flow are inherently difficult to be precisely defined and determined by a decision maker. The main objective in this study is therefore to construct an analytical approach for dealing with the aforementioned managerial problems under subjective judgment environments. Thus, we utilized a fuzzy analytic hierarchy process method to deal with uncertainty. Of primary concern are the criteria of product, equipment efficiency, and finance, and detailed criteria are catered to the requirement for further analysis. Finally, a priority mix of strategic alternatives represented by a priority index can be evaluated. A performance ranking of priority mixes can then be generated. The results provide guidance to select strategies for accepting orders with the consideration of manufacturing efficiency and the aspects of product, equipment efficiency and finance. The model is easily understandable and can be followed by administrators to determine the most suitable priority mix for a fabrication process.     

车身总成组合检具设计方法的研究与应用

基于车身总成件各部件之间的安装关系和各部分的匹配精度,结合实例介绍了一种新型总成组合检具的设计方法。这种总成组合检具能及时发现零件和总成件的设计缺陷,识别和排除存在的问题,同时降低车身制造成本,对车身总成件制造的质量检测和成本控制具有重要的实用价值。     

Controlling Tolerence Stacks for Efficient Manufacturing

Datum-hierarchy (rooted) trees provide a highly efficient and sound basis for tolerance analysis and automated process planning. This paper builds on the previous work by the authors and shows that it is possible to optimise the structure of datum-hierarchy trees automatically. A process planner specifies an initial tree, which is improved upon by using an evolutionary algorithm and is checked against manufacturing and design constraints. A cost function that takes into account machine changes, datum changes and the sum of tolerance stacks drives the mutation process to generate "minimum cost" trees. Experiments were conducted on four industrial parts to demonstrate the feasibility of the approach. The results demonstrate that the method can reduce machine and datum changes and the sum of tolerance stacks. They also show that the order of priority of the cost criteria has a significant effect on the final shape of the trees.     

机加零件三维设计方法

在数字化机械制造时代及人工成本高速增加的背景下,如何在零件设计时就考虑到零件的制造要数,降低零件加工的难度和加工工时,提高生产率和降低生产成本。     

Evaluating Multiple Feature-Based Machining Methods Using an Activity-Based Cost Analysis Model

For a designed part, if different sets of features are used for machining, the manufacturing costs may vary. In this research, the different manufacturing costs for the different feature-based machining methods are analyzed using an activity-based cost model. First, the activities required for machining a set of features are analyzed. Second, the activity-related cost for each activity is evaluated based on a consistent time scale. The summation of costs of the activities equals the manufacturing cost for producing the part. Finally, the different manufacturing costs corresponding to the multiple feature-based machining methods are evaluated. The set of features that can be machined with the lowest manufacturing cost is considered a good way to produce the part. Example parts are tested and discussed.     

基于蚁群算法的模具制造动态调度研究

为解决模具制造动态调度问题,建立了动态调度系统。该系统利用蚁群算法和优先分配启发式算法相结合的调度算法,解决具有工件约束的模具零件的调度问题。该算法首先由蚁群算法确定模具零件各工序所用加工机床,然后利用优先分配启发式算法确定在同一台机床上加工的各零件的先后顺序。考虑动态调度的实时性,提出了局部更新和全局更新相结合的、基于滑动窗口机制的动态调度方法。对于发生频率高但对调度计划执行影响不大的扰动事件采用局部更新策略,反之则采用全局更新策略,在保证获得近优解的同时提高了动态调度的效率。