1735_吊耳加强板零件冲压工艺与冲模设计
1735_吊耳加强板零件冲压工艺与冲模设计,加强,零件,冲压,工艺,冲模,设计
1智能冲压工艺规划系统的研究摘要:本文对建立一个智能冲压工艺设计知识为基础的系统给出了一个简单的介绍。研究该系统的框架,对模型和知识推理模式进行了介绍。对有些关键技术如冲压工艺的可行性、排样的最佳算法、智能地带的布局和内力计算进行了研究。该系统可以改善工艺规划效率。关键词: 排样 KBS 知识模型 带状排样法1 简介冲压工艺规划是冲压产品开发的一个核心项目。它是金属成型应用的一个重要组成部分,它与生产质量、成本、生产率和工具寿命有直接的影响。现代制造业的快速发展对冲压提出了更高的要求,尤其是在冲压工艺方面。多年来,相关研究已就如何在创新的环境加强工艺规划的集成化和智能化程度进行研究。近年来,通过生产金属成形智能设计系统、自动化技术,整和了工艺规划的原则。智能工艺规划方法可以有效地提高设计效率与质量、创新设计能力。1.对于冷锻序列的设计开发了一种基于 PC 的专家系统,该系统采用基于塑性理论和实际考虑的规则。在美国俄亥俄州立大学一个称作 FORMEX 的规则系统被 Altan和他的同事们写入多级冷锻的工艺规划程序语言中。2.它依靠冷锻零件各种形状的广泛分类。3 实施以知识为本的冷成形序列设计系统,采用设计规则确定建立一个可行的序列,然后使用有限元分析优化这个序列。一个以知识为基础的模具设计自动化系统被 Cheok 和他的同事精心设计出来。4 在新加坡国立大学。一些零件表象技术、冲压零件识别和模具构成也存在于这项工作中。在中国,华中科技大学的科学技术研究者们也开发出了基于知识系统的用于对小型金属件冲压级进模的程序包。5.使用特点,用户可以在 3D 立体构架下设计产品。在手工设置排样后,用户可以使用交互命令来开发带装布局设计。来自利物浦大学工业研究部门的研究者们也在研究冲压工艺和冲裁模的专用系统。6.他们的研究集中在分解较小的桥型废料的形状编码和识别技术。7在上海冲压模具和工具技术研究所的研究者们也开发出了级进模的 CAD/CAM 系统。他们研究的该系统依靠特殊的相关数据来描绘工件和模具结构。上述研究的研究工作的目的是为了促进金属成形的发展。从金属智能成型的回顾和分析中,使用智能设计的理论和方法来研究冲压工艺规划的步骤。在本文中介绍了应用于冲压工艺规划的智能的系统。该智能系统在处理一些复杂的设计问题时是种强有力的工具。由专门知识构成的智能系统可以用一种交互的方式协助用户解决各种各样的问题或疑问。8.智能系统是一种计算机系统,它试图代表人类知识和专业知识, 以一种实际和有效的途径提供快捷、方便的知识。智能系统能够完成一般需要专家才能完成的任务。它能自动化实时利用现有的专业知识,并解释它的推理过程。冲压工艺2规划是一个含有丰富知识的复杂设计过程。整合在冲压工艺规划设计中智能系统的关键技术是至关重要的。使用智能理论的冲压工艺规划智能系统被提出来。对一些关键技术,如集成产品知识建模和战略规划的综合冲压成形过程进行了研究。在冲压设计中包括各种各样的知识,如专业领域知识、多任务知识、非标准知识。每一种知识都需要集成到该系统中。冲压模具的核心是冲压工艺。必须考虑到多种因素,如几何形状、技术要求、材料性能、冲压件的可行性、工作程序安排、模具工具的结构。冲压工艺规划是一种基于专家知识的创造性程序。智能系统技术可以改善制定冲压工艺规划的效率。2 系统构架和框架智能系统的关键技术是建立和应用的信息化模型制作。 。该产品信息模型,包括三个阶段:一种基于几何的模型、一种基于特征的模型、一种基于智能的模型。基于几何的模型描述零件的几何拓扑信息。由于零件的数据信息不能被完整的描述、数据分离水平太低,几何模型被特征模型取代。这个信息模型包括一组几何实体。依靠此模型的工程语义模型,许多与设计相关的功能可以被实现。随着人工智能的发展,智能模型开始被应用。专业知识、设计过程的知识,和相关的知识都包含在知识模型中 9、10 。智能模型支持表达和传递有用的信息。本文主要概括了一种冲压工艺规划的智能系统。该智能系统对产品的定义有效且完整。它几何了不同模型的优点且能满足几何设计和推理过程。面向对象技术应用到整合各种各样的知识。此集成的知识系统模型可被共享和用于智能设计和产品信息沟通。这个关于冲压模具工艺规划的智能系统构架已经被设计出来。这个零件的结构设计,包括一个图形用户界面,一个应用程序系统、设计资源、知识工具,混合推理机制、基础模型。在这个构架中知识模型有不同的分类。知识模型从设计资源中获取有用的信息,支持知识获取和知识表达的程序。这个模型把有用信息转移到知识库。知识库由 CAD 软件支持。设计结果以 3D 模型、图画和资料库的形式保存在知识库中,它对在知识库中不同零件的知识传递来说非常的重要。3 实施方法和应用3.1 冲压智能模型的可行性论证智能系统对冲压工件的质量、成本、模具寿命进行评价。该评价基于成熟的智能模型。此模型集成了规则库、零件信息和结论库。系数根据知识规则推理在知识库得出。冲压成型可行性可以从信息库中零件信息和相关系数推出。在设计过程中被新结论扩大的结果保存在结论库中。3模型的智能推理过程和零件的规格相比有一定限度范围的工艺参数。此规格包括输入输出半径、孔径、孔板、孔网、槽、槽网。结果来证实零件的形状是否符合模具工具加工。智能推理用于自动和交互的方式。这样做的目的是来研究冲压该产品的可行性。智能推理的关键是确定基于零件厚度和相关系数的加工极限值。图二所示为产品可行性论证模型的流程图。知识规则和设计结果保存在机械推理的数据库中。零件的形状可以在知识模型中修改。由知识模型决定的冲压工艺规划是非常重要的一步,它同时也提供了选择一个单步工序刀具或是复合工具或是一个改进工具的方法。各种不同领域的知识、经验和专业知识都被保存在工艺规划专业系统中。知识库的发展是基于规则表达的共同原则。这一步的目的是集成专业经验和零件的形状3.2 基于优化算法的智能排样模型为了达到较高的材料利用率,空白的知识模型被建立,保存在知识库中的结果是其他模块建立的基础。在知识库中有四种排样类型: 一排列布局模式 与一排列相对的模式 两排列布局模式 与两排列布局相对的模式建立这个知识模型的目的是改善材料的利用。由知识库提供的限制情况可以由人类专家来选择。这个知识模型控制着整个排样的设计过程。图三所示为平面布局的等级体系结构第一种模式的作用是选择粗略数值和计算工作区域的总体轮廓。此模式提供了原始参数。粗略数值的全部信息都由此得到,不管这个数字是否被概略画出或是被选中。第二种模式用来确定布局类型、角度范围、布局大小和条带区的宽度。第三种模式中应用了优化算法。设计结果包括材料利用率、材料宽度和每步间隙都被保存在此模式中,不同布局的绘图也同时生成。在第四种模式中可以修改布局规划的结果。最终参数包括每步间隙、材料宽度、各类网格和转换能力。当参数有所改变时,布局规划图可以被更新。该知识的主要作用是布局规划的算法优化。该算法共有六步。1.在图形周围最适合的矩形第一次生成。复制件和原件之间的距离是包含在接洽4网中的。图四说明了此种算法。2.在两个环形中间的值是经过计算的。这两个环形分解成线和圆弧的单元。每对元素中间的距离需要重新补偿。然后就可以找到最短的距离。3.计算出的最小值和所要求的值之间的差异就是误差。当误差小于允许值时,排样规划就可以完成。另外,布局图形需要沿着视野的方向移动。4.材料利用率可以以布局规划的角度上被计算出来。5.排样图形旋转一定的角度。旋转中心是矩形中心点附近的粗略数值。材料利用率在当前角度下被计算出来。6.排样图形旋转到另外一个角度。重复第三部的的步骤,直到角度达到 180 度。 3.3 带状布局的开发带状布局的工序规则被集成于知识基础级进刀具设计。该智能模型的功能是:选择零件位置,设计方位和安排带状工步距离。为了解决运行程序,该规则应该被制定的合理和有效。自动设计模块是智能模型中最重要的模块。人工智能技术被应用于此模块中。此模型中的预处理模块,包括定位产品模块和从产品模块中提取精确的信息。为了在修改模块中生成一个模型,最初的设计工程被修改11 。被修改的模块代替了处理模块。3.3.1 自动带状布局设计的预处理1)确定零件的位置和排列。用户可以用界面来确定预处理模块中的一些参数。确定位置的过程可以和其他元素一起来做,例如:零件形状、尺寸精度、和用户要求。零件的形状也在智能模型中定义,结果被保存在知识库中。2)获取零件精确信息。此精确信息应该在带状布局知识库中得到。有用的信息包括冲孔的精确信息和相对位置信息。由此种类型信息组成的知识模型将会决定零件的冲压顺序。这个设计过程的主要要求是为位置精度开发一种知识模型12。首先,零件的形状被分成封闭的轮廓。轮廓的数目为 nK = k1, k2, . . ., ki, . . ., kn (1)这里 ki 表示零件的第 i 个轮廓。所有轮廓间的相对关系包含在关系 P 中。如果在轮廓 ki 和 kj 之间要求精准,这里存在( ki , kj) p。p = . . ., (ki , kj), . . . ki , kj K, 1 i, j n(i _= j). (2)每种类型的精确信息通过相关矩阵被保存在知识模型中。3.3.2 带状布局自动设计带状布局的自动设计模块在知识模型中是最重要的一个。在知识模型中包含很多重要的规则,例如在一次单冲程中冲压所有内轮廓比较好。在下一个阶段这个部分被切断。有时候,如果冲压点之间的距离非常小,一些内轮廓就要被搬到下一阶段进行加工。如果冲压点离分馏点太近的话,分馏点就需要被更改到下一阶段。如果这里仍5然有不合适的尺寸,一些点可以被移动到下一阶段。重复整个过程直到矩阵点间的每个尺寸都可以被接受。布局智能设计的核心是开发干涉点的智能模型13。零件坯料被分成许多点的形式。这些点的名字是 k1, k2, . . ., kn. 这里 dij 是 ki 和 kj 之间最小的距离。矩阵的临界值是 S。如果 dijS ,ki 和 kj不能在相同的步骤中得出。这种情况是智能模型中两个点的冲突。开发干涉点的智能模型的目的是确定冲突点的存在。此矩阵是一个系统矩阵。为了使设计过程更方便,可以把矩阵中的上半部分元素置零。此处, ij 是关联系数,它表示了每对点之间的不同关系。如果两个点之间有冲突,它们中的一个则要被移到下一步。在每一步中重复上述步骤直到冲突点消失。最后矩阵 M 成为空矩阵。3.3.3 对带状布局结果的处理带状布局的子处理知识模型中有两部分:修改结果和创建布局图形。从带状布局自动设计模型中得出的结果是惯用的。它们可能满足不了用户的所有要求。依靠知识模型的数据结构,通过移动点和改变步骤,增加空步和删除空步的目的可以被实现。我们能够通过处理步骤的数据结果来修改带状布局的设计结果。工步改变可以通过交换两个位置的编码来实现,工步增加或减少可以通过插入或移除编码的操作来完成。当我们想移动一些点时,我们可以从第一步到最后一步转移链表中相当的点。3.4 确定冲压中心和力计算的智能模型。冲压中心设计模型的目的是建立组合力的工作点11。模具工具中心和冲压中心的一致非常重要,只有那样冲压工具才能在一起正常的工作。冲压中心从知识模型的每一个轮廓位置的计算中得出。设计的第一部是得到工具的工作区域。CAD 平台上的零件图形的轮廓提供了零件的外矩形。依靠冲压中心和外矩形之间的关系可以生成工作区域。因为不平衡力的结果的可能性,同时也提供了冲压中心的再生成。再生成的步骤由人机接口软件来完成。图八所示为复合模打孔机工 作区域的设计结果。保存在知识库中的内容包括模具工具的每种类型、零件落料、废料移除等等。不同情况下的力计算的方法是不同的。力方程是由知识规则库的推理得到的。首先,加工力和切削力是基于零件的轮廓长度和知识库中的知识规则得到的。然后,通过设计结果和合零件情况,可以得到脱离力、阻力和推件力。总的力按照知识库中的导向一步一步计算。4 结论和进一步工作计算机辅助设计工具的应用在金属成型中的应用,节省了大量的时间和金钱。由于复杂零件冲压工艺设计的复杂性,开发一种自动生成工艺步骤的系统非常重要。这个研究开发了一个集成的 CAD 系统,该系统开发了一种工艺规划系统使对不规则零件6在高速下进精密加工得以实现。该系统有一下特点:1. 在设计过程中不断改变的数据以不同的方式保存,包括数字形式和图片形式的。用户在设计过程中可以自由使用它们作为参考。2. 加工可行性检查模型检查冲压的可行性,同时能对复杂零件的冲压工艺规划提供一些建议。3. 排样模块生成最佳排样图以到达材料的最大利用率。产品成本的减少取决于排样最优化计算。不仅最佳规划而且每个合理的规划被保存在知识库中。用户可以选择任意一个作为它们的最终设计结果。4. 带状排样模块生成自动工艺规划图。根据用户的要求带状排样的结果可以在设计过程的任意时期修改。在工艺规划中协助设计者的此系统将会是一种有用的工具。它将会足够的灵活允许设计者具有创造性,同时用计算机来执行几何计算和自动得到设计结果。它提供了一个非常灵活的设计环境,用户可以完全掌握即使是复杂零件的冲压工艺规划设计。该系统拥有图形交互界面,用户可以在设计过程中交互式地改变各种设计参数。进一步的工作将会集中在排样优化的效率改善上,优化用时将会减少。为排样规划,更多的设计方案的类型应该被添加到知识模型中。根据冲压工艺规划的结果,冲压模具设计应用也将会在进一步的工作中被研究。7Intelligent stamping process planning system research Abstract: this paper to build a intelligent stamping process design knowledge based system gives a brief introduction. Study the system framework of model, and knowledge reasoning model are introduced. For some key technologies such as the feasibility of stamping process and exhaust kind of best algorithm, intelligent zone layout and internal force calculation is studied. This system can improve process planning efficiency. Keywords: arrangement a KBS knowledge model ribbon arrangement method introduction Stamping process planning is one of the core punching product development project. It is the metal molding application an important component part of it and the production quality, cost, productivity and tool life have direct influence. The rapid development of modern manufacturing for stamping put forward higher request, especially in stamping process. For many years, the related research has the environment in innovation to strengthen the integration and process planning study intelligentize degree. In recent years, through the production of metal forming intelligent design system, automation technology, the whole and the process planning principles. Intelligent process planning method can effectively improve the design efficiency and quality, innovative design ability. 1. For cold forging sequence of designing and developing a kind of expert system based on PC, this system based on practical considerations plasticity theory and the rules. At the Ohio state university, a called FORMEX rules system is Altan and his colleagues write multistage cold forging process planning and programming language. 2. It depends on a cold forging parts of various shapes widely classification. 3 implement knowledge based cold forming sequence design system, adopting the design rule sure to establish a feasible sequence, then using finite element analysis optimization this sequence. A knowledge based mold design automation system is Cheok and his colleagues carefully designed. 4 in the national university of Singapore. Some parts representation techniques, stamping parts recognition and mould constitute also exists in this work. In China, huazhong university of science and technology researchers also developed based on knowledge system for small metal parts stamping progressive die program packages. 5. Use features, users can under 3D architecture design products. In manually set arrangement, user can use interactive command to development zones outfit layout design. From Liverpool university industrial research departments researchers are also studying stamping process and punch die special system. 6. The focus of their study in decomposed smaller bridge waste shape coding and recognition technology. 7 in Shanghai stamping mould and tools institute of technology researchers also 8developed progressive die CAD/CAM system. They study the system depend on special relevant data to describe the workpiece and mould structure. The findings of the research work purpose is to promote the development of metal forming process. From metal intelligence review and analysis of the forming of intelligent design, use the theory and method to study the stamping process planning steps. In this paper introduces applied in stamping process planning of intelligent system. This intelligent system in dealing with some complex design problem is a powerful tool. By special knowledge construction intelligent systems can use an interactive way help user to solve all kinds of problems or questions. 8. Intelligent system is a computer system, it tried to represent human knowledge and professional knowledge, and to a practical and effective way to provide fast, convenient and knowledge. Intelligent system can accomplish generally require experts to complete tasks. It can automatic real-time use existing professional knowledge, and explain its reasoning process. Stamping process planning is a rich knowledge of the complex design process. Integration in the stamping process planning and design of the key techniques of intelligent system is of vital importance. The use of intelligence theory stamping process planning intelligent systems have been proffered. Some key technologies, such as integrated product knowledge modeling and strategic planning comprehensive stamping process was studied. In stamping design including all kinds of knowledge, such as domain knowledge, multitasking knowledge, non-standard knowledge. Each kind of knowledge all need to be integrated into the system. Stamping mould that is the core of stamping process. Must consider the various factors, such as geometry, technical requirements, material properties and stamping feasibility, working procedures arrangement, the structure of mould tool. Stamping process planning is a kind of creative program based on experts knowledge. Intelligent system technology can improve the efficiency of the stamping process planning. 2 system frame and the frame Intelligent system key technology is built and application of information model making. This product information model, including three stages: a kind of the model, based on geometric model based on features based on intelligence, the model. Based on geometric model describing the geometric topology information parts. Because parts of data message cannot be fully described, data separation level is too low, geometric model was characteristic model replaced. This information model includes a set of geometric entities. Rely on this model, the engineering semantic model with design of related functions many can be realized. Along with the development of artificial intelligence, the intelligent model begins to be used. Professional knowledge, design process of knowledge, and relevant knowledge are included 9in the knowledge model 9, 10. Intelligent model support expression and transfer of useful information. This paper mainly summarizes a stamping process planning of intelligent system. This intelligent system for product definition effective and complete. It has the advantages of different geometrical model and can satisfy the geometric designs and reasoning process. Object-oriented technology is applied to integrate all kinds of knowledge. This integrated knowledge system model can be Shared and used in intelligent design and product information communication. Figure 1 shows the stamping process planning intelligent system frame This about stamping mould process planning of intelligent system frame has been designed. The components of the structure design, including a graphical user interface, an application system, design resources, knowledge tool, mixed reasoning mechanism, basic model. In this architecture knowledge model have different classification. Knowledge model from the design resource to extract useful information, support knowledge acquisition and knowledge expression program. This model is useful information transferred to knowledge. Comprising CAD software support. Design results as a 3D model, pictures and database is stored in the repository, it in different parts of the knowledge base is very important knowledge transfer. 3 implementation method and application 3.1 stamping feasibility of intelligent model Intelligent system for stamping workpiece quality, cost, die life is evaluated. This evaluation based on mature intelligent model. This model has integrated rule library, parts information and conclusion library. Coefficient of knowledge rule reasoning in knowledge according to that. Stamping forming feasibility can from a database of information and related coefficient parts launch. In the design process of the extension of the new conclusion preserved in conclusion library. Model of intelligent reasoning process and parts specification limits range compared with the technological parameters. This specification Including input/output radius, aperture, orifice plate, hole nets, chamfer, trough nets. Results to confirm whether accord with the shape of mould parts processing tools. Intelligent reasoning is used in the automatic and interactive way. Its purpose is to study the feasibility of pressing the product. Intelligent reasoning based on the key is to determine the thickness and the correlation coefficient parts processing limit. Figure 2 shows the feasibility of the model for product flow chart. 10Figure 2 shows the feasibility of the model for product flow chart. Knowledge rules and design results stored in the database of mechanical reasoning. Parts in knowledge model shape can modify. The decision by the knowledge model stamping process planning is very important step, it also provides to choose a single step process tool or composite tools or a method of improvement tools. All sorts of different domain knowledge, experience and expertise are kept in the process planning of professional system. Based on the development of knowledge base is the common principle rules expression. The purpose of this step is to integrate professional experience and parts shape 3.2 based on optimization algorithm of intelligent strip layout model In order to achieve higher material utilization, blank knowledge model was established, the results are stored in knowledge base established basis other modules. In the knowledge base there are four arrangement type: Arranged layout pattern determined With an array of Washington relative pattern Second-ranking arranged layout mode two With two second-ranking arranged layout relative mode The purpose of establishing the knowledge model is to improve the material utilization. The restrictions by knowledge can provide human experts to choose from. This knowledge model control over the whole arrangement design process. Figure 3 shows the layout rating system structure The first kind of mode selection function is roughly calculated the numerical and working area general outline. This model provides the original parameters. All the information is roughly value resulting from them, no matter the figures are outlined draw or selected. The second mode used to determine the layout type, Angle range, layout size and strip the width. The third kind of mode applied optimization algorithm. Design results include material utilization, material width and every step clearance are kept in this mode, the different layout drawing also generate. In the fourth mode can modify layout results. Eventually parameters include clearance, material each step of grid, and the width, the ability to switch. When the parameters change, layout plans can be updated. 11This knowledge is the main purpose of the algorithm to optimize the layout planning. This algorithm six steps. 1. The most suitable around in graphics rectangular first generation. The original copy and the distance between the approach is included in the net. Figure 4 shows the algorithm. 2. The value of the two ring is among a computation. The two ring is decomposed into line and arc units. The distance between each element needs to compensation. And then you can find the shortest distance. 3. The minimum value and calculated the value of the required the difference between is error. When the error less than value, arrangement planning can be completed. In addition, graphic layout to follow the direction of the view movement. Graph 4: arrangement algorithm. A primitive Angle graphics. B rotation Angle of graphics after 4. Material utilization in layouts point of view is calculated. 5. Arrangement graphics rotating certain Angle. Rotating center near the center is the rectangular roughly value. Material utilization in the current Angle was calculated. 6. Arrangement graphics rotated to another Angle. Repeat the steps of the third part, until Angle reached 180 degrees. Figure 5 shows is the arrangement design results. Graph 5: row kind of intelligent design results. The development of 3.3 ribbon layout The layout of the shingles rule was integration process in knowledge base level into tool design. This intelligent model function is: select parts location, design azimuth and arrange ribbon work step distance. In order to solve the operational procedures, and the rules should be reasonable and effective formulated. Automatic design module is intelligent model in the most important modules. Artificial intelligence technology has been applied in this module. This model, including the pretreatment module orientating products module and extracted from the product modularization accurate information. In order to modify module generates a model, initial design engineering is modified 11. The modified module instead of processing module. Figure 6 shows the layout of the model and the algorithm for shingles. 3.3.1 automatic ribbon layout design preprocessing 1) determine the position and permutations. Parts The user can use interface to determine some of the preconditioning module parameter. The process can determine the position and other elements, such as: to do together shape and size accuracy, parts and user requirements. 12Parts in the shape of the intelligent model definition, the results are stored in a knowledge base. 2) get parts precise information. The precise information should get in ribbon layout knowledge base. Useful information including punching accurate information and relative location information. This type of knowledge model of information will decide parts stamping sequence. The design process is the main requirements for the position precision to develop a knowledge model 12. First, the shape of the parts were divided into closed contour. Outline the number of n K = k1, k2,., ki,., kn (1) Here the first I ki says parts an outline. The relative relations between all contour contained in the relationship of P. If in contour kj ki and precision, there exists between requirements ki, kj) (p. P = ., (ki, kj),. ki, kj K, 1 acuities were I, j acuities n (I _ = j). (2) The position precision from P get relevant matrix is: (3) Each type of accurate information through the correlation matrices is preserved in knowledge model. 3.3.2 ribbon layout automatic design Ribbon automatic placement design module in the knowledge model is the most important one. In the knowledge model contains a lot of important r
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