CAD知识的模具设计英文文献和中文翻译(4)
The second section whichdescribes the relation between the part and the mould includesthe fifth digit. The third section which describes the mouldcontains the last seven digits.5.4.1 The First Section: Part DescriptionThis section includes the first four digits. They represent thepart class, part external shape, undercut features and materialclass, respectively.5.4.1.1 Part Class. The first digit distinguishes the part as acircular part or a non-circular part. There are seven numericpositions for this digit as shown below.1. Circular part with H/D # 0.52. Circular part with 0.5 , H/D , 33. Circular part with H/D $ 34. Variational circular part5. Non-circular part with H/De # 0.56. Non-circular part with 0.5 , H/De ,37. Non-circular part with H/De $ 3Here, H is the height of the part measured from the partingline, D is the diameter of a circular part, De is the equivalentdiameter of a non-circular part with length L and width W (De=√(4LW/p)). Parts belonging to class 1 and class 3 are likeflat disks and long cylinders, respectively. Parts belonging toclass 5 and class 7 are like flats and long prisms, respectively.5.4.1.2 Part External Shape. The second digit depends onwhich class the part belongs to and the classification rules areas follows:Class 1–31. Smooth, having a uniform diameter along the entire height.2. Cone, diameter stepped to one end.3. Having various diameters along the entire height.Class 41. Curved rotating axis.2. More than one parallel rotating axes.3. More than one non-parallel rotating axes.Class 51. Rectangular with no deviation in corner.2. Rectangular with one deviation right-angle or triangular.3. Rectangular with circular deviation.4. Flat part, regularly arched or dished.5. Irregular contoured flat part.Class 6, 71. Straight axis, uniform cross-section, no deviation in corner.2. Straight axis, uniform cross-section, with one deviation.3. Straight axis, uniform, other than rectangular cross-section.4. Straight axis, varying cross-section stepped to one end.5. Straight axis, varying cross-section along the entire height.6. Curved axis.5.4.1.3 Undercut Feature. Mould designers are frequentlyfaced with demoulding problems resulting from undercuts exist-ing on the plastic parts. An undercut can be defined as anyinterference occurring between the mould and the mouldedpart when the part is knocked out from the mould in thewithdrawal direction. The design of an appropriate mould forthis type of product is inevitably more complicated than forthose without any undercuts. In general, undercuts can beclassified into three types, external undercut, internal undercut,and internal thread. The undercut feature is represented by thethird digit which has the following positions.1. External undercut only.2. Internal undercut only.3. Internal thread only.4. External undercut and internal undercut.5. External undercut and internal thread.5.4.1.4 Material Class. Plastic material used for mouldingthe part is classified according to its material constant n. Thereare four positions for this digit.Position 1 2 3 4Material constant n 0.6 0.7 0.8 0.95.4.2 The Second Section: The Relationship Betweenthe Part and the MouldThe fifth digit describes the relation between the directions ofthe part axis and the mould parting line and is classified as:
本文介绍了一种实用的以知识为基础的原型系统，称为ikmould，在注塑成型过程中模具的设计。它试图解决的问题，在一个实际的和综合的方式，不像在过去已经开发出来的独立和数学程序，只解决一个问题的一部分。全定量结构化的方法是不可行的，在处理复杂设计问题一般涉及模具设计。在这个系统中，计算模块，以知识为基础的模块和图形模块的生成模具功能集成在一个互动的计算机辅助设计为基础的框架。本系统的知识库可以通过模具设计师通过互动节目使他们自己的智慧和经验也可以纳入总的模具设计。该方法加快了设计过程，使设计标准化，这反过来又增加了模具制造的速度。