现代模具设计方法
第五章 级进模CAD软件的结构与操作步骤 ························································ 144 第一节 级进模CAD软件的结构 ·············································································· 144
一、 级进模设计内容及过程分析 ······························································ 144 二、级进模CAD系统的功能模型 ······························································ 144 三、系统组成 ································································································ 146 第二节 零件预处理 ··························································································· 149
一、直接展开（Direct Unfolding） ····························································· 149 二、 练习1：识别折弯和建立工步的装配 ··············································· 153 三、 折弯操作 ······························································································ 157 四、练习2：建立中间工步 ········································································· 158 第三节 初始化项目 ····························································································· 161
一、初始化项目 ···························································································· 161 二、练习3：零件项目初始化 ····································································· 164 第四节 级进模的毛坯导入和布局 ····································································· 166
一、毛坯生成器 ···························································································· 166 二、 练习4：以零件为毛坯 ······································································· 167 三、毛坯布局（Blank Layout） ·································································· 168 四、练习5：单排排样的毛坯布局 ····························································· 171 第五节 级进模的废料设计 ················································································· 172
一、废料的创建 ···························································································· 172 二、练习6：废料创建 ················································································· 174 三、废料的编辑 ···························································································· 175 五、废料的工艺处理 ···················································································· 177 六、练习8：工艺处理 ················································································· 178 七、废料的分组 ···························································································· 179 八、练习9：废料分组 ················································································· 179 第六节 级进模的条料排样 ··············································································· 179
一、条料排样 ································································································ 179 二、练习10：创建仿真条料 ······································································· 183 第七节 级进模的冲压力计算 ··········································································· 187
一、冲压力计算 ···························································································· 187 二、 练习11：计算冲压力 ········································································· 189 第八节 级进模的模架设计与管理 ····································································· 193
一、设计模架 ································································································ 193 二、练习12：设计模架 ··············································································· 195
第五章 级进模CAD软件的结构与操作步骤
三、冲模设计设置 ························································································ 197 第九节 级进模的冲裁镶块设计 ······································································· 198
一、 凹模镶块的设计 ·················································································· 198 二、练习13：设计冲裁凹模 ······································································· 200 三、练习14：凹模镶块型腔废料孔的设计 ··············································· 204 四、 凸模镶块的设计 ·················································································· 207 五、练习15：设计冲裁凸模 ······································································· 209 六、冲裁镶块的关联设计 ············································································ 210 第十节 级进模的折弯镶块设计 ········································································ 211
一、标准镶块 ································································································· 211 二、 删除 ······································································································ 213 三、练习16：创建折弯凸模和凹模 ··························································· 213 （6）创建第6工位镜像的折弯凸模 ·························································· 221 第十一节 级进模的镶块辅助设计 ··································································· 223
一、镶块刀柄 ································································································ 223 二、复制与删除 ···························································································· 223 三、练习17：创建倾斜类型的镶块刀柄 ··················································· 224 四、 练习18：创建后角类型的镶块刀柄 ················································· 227 第十二节 级进模的标准件设计 ······································································· 229
一、标准件概述 ···························································································· 229 二、练习19：安装标准件 ··········································································· 234 第十三节 级进模的腔体设计 ··········································································· 248
一、腔体设计 ································································································ 248 二、练习20：在冲模板中创建安装槽 ······················································· 251
第五章 级进模CAD软件的结构与操作步骤
第五章 级进模CAD软件的结构与操作步骤
第一节 级进模CAD软件的结构
开发任何CAD系统，首先必须对所开发的系统进行功能需求分析，以确定系统的范围、功能、输入、输出、需解决的关键技术问题等。对于级进模CAD系统而言，其功能需求分析一般包括以下内容：①分析级进模的设计内容及一般过程；②建立系统的功能模型；③确定系统总体结构。
一、级进模设计内容及过程分析
级进模设计主要包括：钣金零件的冲压工艺性分析、毛坯展开、毛坯排样、条料排样、模具总装结构设计、工作部件设计、辅助装置设计、零件详细设计等。
钣金零件冲压工艺性分析，主要是判定钣金零件是否适宜采用冲压加工方法制造。采用级进模加工，钣金零件形状必须满足一定的要求，如形状大小、圆角半径、孔间距等。若零件形状不满足冲压工艺要求，则需要修改零件形状,或改用其他加工方法。
钣金零件是由平板毛坯经冲压加工而成，因此，在设计其冲压成形工艺时，需首先将其展开成平面形状，以便确定毛坯的尺寸和形状。展开尺寸的精度会直接影响制品的加工精度。目前，尚未有精确的计算方法，通常是先采用经验公式或数据计算，然后再通过试模逐步确定最后的展开尺寸。
条料排样确定毛坯逐步冲压成形的过程，是级进模设计中最关键的设计内容，也是最难的设计内容之一。条料排样的结果基本上确定了模具的结构形式，其设计的好坏，将直接影响冲压加工零件的质量。在条料排样时需考虑冲压工序、载体形式、模具结构的复杂程度、以及模具制造工艺性等问题，同时还要考虑如何保证条料在冲压成形过程中能顺利平稳地送进，协调地完成各工位的加工动作。
模具结构及零件设计是在条料排样的基础上，确定模具的总体结构以及各零部件的形状及安装方式。在进行模具结构设计时，需首先选择模具的结构形式，包括送料、卸料、顶料、导向及定位等方式的选择，然后确定凸模和凹模的形式（如整体式、拼块式及镶拼式），最后设计其他相关的辅助装置，如安全监测装置、限位装置等。
上述设计内容及过程与其他相关过程的关系见图5-1所示。
二、级进模CAD系统的功能模型
虽然级进模的设计过程按其设计内容可分为毛坯展开计算、毛坯排样、条料排样、总装设计和零件详细设计等步骤，但在实际的设计过程中，设计人员在每一设计阶段，通常都需要考虑后续阶段的有关设计内容，有时只有在后续的设计活动中才能发现前一阶段设计中存在的问题。采用IDEF0方法对这一复杂的设计过程进行分析，可建立开发级进模CAD系统的功能模型，确定所开发系统的功能要求，以指导系统的整个开发过程。
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现代模具设计方法
冲压零件图 包括技术条件 模具设计任务书 产量、批量、冲床条件、送料方式、其它 试制或小批量生产的冲压技术数据和样件 模具设计 车间 以简易模做工艺验证或人工进行工艺性校验 工艺计算 计算绘制零件展开图 设计绘制零件展开图 模具工艺 工艺性会审 工艺性会签 模具工艺编制 模具结构设计 校对 审核 绘制装配草图 绘制模具装配图零件图 编制使用维护说明书 全部资料存档 描图晒图 生产准备 车间制造 图5-1 级进模设计过程简图
1.IDEF0方法
IDEF0方法是一种描述系统功能活动及其相互关系的结构化分析方法。在系统分析过程中，严格按照自顶向下逐层分解的方式，由整体到局部的对系统进行全面分析。分析结果以IDEF0模型表达。IDEF0模型是由一系列图形组成。最基本的图形单元为一个方盒和与该方盒连接的一组箭头组成，它代表了一个功能模块，如图5-2所示。图中，方盒表示系统的功能，而箭头则分别表示该功能模块所关联的输入、输出、控制和机制。其中，输入是指该活动所需的信息；输出则是指输入信息经该功能模块处理后所产生的信息；控 制是指该功能模块执行的条件和约束；机制则是指该功能模块是由什么来完成的。在IDEF0模型中，一个模块与其他模块间的关系通过互相联结的箭头来表示。而当一个模块被分解成几个子模块时，则用一组编号来表达它们之间的对应关系，如图5-3所示。
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