电机壳体冲压工艺及模具设计毕业论文
2021-04-28 20:52:33
摘 要
这次毕业设计论文的题目是电机壳体冲压工艺及模具设计,也就是说本论文的主要内容是就电机壳体的冲压工艺分析展开的。提出一种良好的复合冲压工艺,并且设计一副符合要求的冲压模具是本论文的主要内容。
由零件结构以及工艺特性的分析,从而提出了设计落料、拉深、冲孔、整形复合模具的方案。这种复合模具大大的减少了工艺流程,避免了因模具调试与模具磨损造成的制品质量低和平面度与径向圆跳动值超差的情形。既然确定了这种复合模具的方案,设计模具就此展开。了解模具的基本结构后,熟练的运用冲压模具的设计方式和步骤结合各种规范以及标准设计出复合模具的各个部件,以达到完成复合模具设计的目的。这次毕业设计是一次很好的查漏补缺的过程,并检查了知识的实际运用能力。
关键词:
电机壳体 冲压工艺 复合模具
Abstract
The topic of this graduation design thesis is stamping technology to shell of electrical machine and die design that is the main content of this thesis starts with the analysis of stamping technology to shell of electrical machine. Put forward a kind of good compound stamping technology. And the design of a pair of stamping die is the main content of this thesis.
The design of blanking, drawing, punching and shaping compound die is presented by analyzing the structure and process characteristics of the parts. This kind of compound mould greatly reduces the process flow, and avoids the bad quality of products caused by die adjustment and die wear, and the situation of the plane degree and the radial circular run out. Since it is determined that this compound mould, the design of the mold to start. Understand the basic structure of the mold, skilled use of stamping die design methods and procedures in combination with a variety of specifications and standards to design the various parts of the complex mold, in order to achieve the purpose of composite die design. This graduation design is a process of good leak filled, and check out the knowledge of the actual ability to use.
Key Words:
shell of electrical machine stamping technology compound mould
目录
摘要···································································Ⅰ
Abstract·······························································Ⅱ
第一章 绪论·····························································1
1.1 冲压概述························································1
1.2 冲压成型的特点··················································1
1.3 冲压变形的分类··················································2
1.4 模具在冲压方面的发展············································3
第二章 零件工艺分析·····················································4
2.1 零件工艺性分····················································4
2.2 工艺方案的确定··················································4
第三章 主要工艺参数的计算···············································6
3.1 毛坯尺寸的计算··················································6
3.2 计算拉深系数····················································6
3.3 确定排样方案····················································6
3.3.1 确定排样方案··············································6
3.3.2 材料利用率················································6
3.4 拉深冲压力的计算················································7
3.4.1 落料过程··················································7
3.4.2 拉深过程··················································7
3.5 冲压设备的选择··················································7
第四章 模具工作部分尺寸及公差计算·······································9
4.1 落料凸、凹模刃口的尺寸及公差的计算··························9
4.2 拉深凸、凹模刃口的尺寸及公差的计算··························9
4.3 冲孔凸、凹模刃口的尺寸及公差的计算··························9
第五章 复合模具主要零件的设计···········································9
5.1 落料凹模的设计···············································11
5.2 凸凹模的设计·················································11
5.3 凸模的设计·····················································11
5.4 模柄的选用·····················································12
5.5中间固定板的设计················································12
5.6 橡胶的设计·····················································13
5.7 垫板···························································13
5.8 工艺零件与结构零件··············································13
第六章 落料拉深整形冲孔复合模装配·········································15
6.1 冲压模具装配的技术要求·········································15
6.2 落料拉深整形冲孔复合模装配的特点·······························15
6.3 复合模具的总体设计·············································16
6.3.1 模架尺寸的确定···········································16
6.3.2 定位零件·················································16
6.3.3 推件、顶件装置···········································16
6.3.4压边装置的设计············································16
6.4 模具的调试要点·················································16
结论·······································································18
参考文献··································································19
致谢······································································20
第一章 绪论
1.1 冲压概述
冲压是靠压力机以及模具来对带材、板材、型材以及管材等使用外力,使其发生塑性变形或是分离,为了获得所需尺寸及形状工件的成形加工方式。一般情况下冲压是在常温下对材料进行的一种冷变形加工,也可以称为板料冲压或是冷冲压。冲压作为塑性加工或是材料压力加工主要方式之一,是一种材料成型工程术。只有当板材厚度超过8~100mm的时候,这时才使用热冲压。
在金属制品各行业中冲压应用广泛,尤其在仪表、汽车、家用电器、军工这些工业中占有很高的地位。在板料压力加工以及材料塑性加工中,冲压加工占据着相当高的地位。冲压成形需要研究三类基本问题:工艺设备、冲压材料以及模具。
冲压加工拥有这些特点:1冲压件在尺寸与形状方面拥有良好互换性 2可加工形状复杂、薄壁的零件3材料利用率高4能得到质量轻且刚性好、强度高的零件5操作简单,生产率高,容易实现自动化与机械化。
冲压模是在冲压加工时所使用的模具,可简称冲模。冲模作为使材料发生变形或分离的工具或模型,在冲压加工的工艺装备很重要,没有达到要求的冲模,就很难进行批量冲压加工;而没有先进的冲压模具,就无法实现先进的冲压工艺。冲模的制作成本很高,因此大批量生产较为合适。对于多品种、小批量生产,使用简易冲模就可以,并且引进冲压加工中心这些新型设备,来达到市场求变求新的需要。冲压生产设备分为剪床与冲床。剪床针对于剪切板材成具有一定宽度的条料,用来让后续冲压工序加工,冲床则能成形及剪切。
1.2.冲压成形的特点
在生产实践中冲压成形工艺方式有多种多样,具有很多形式的名称,但一样的是其塑性变形本质。冲压成形具有这几个相当突出的特点。
(1)垂直于单位面积板面方向上的压力,其值不大就能在该方向上使板材有塑性变形发生。因为垂直于单位面积板面方向上的压力远低于在板面方向上的内应力,因此大部分的冲压变形都可以近似当做平面应力状态来处理,大大的简化其工艺参数的计算工作与变形力学的分析。
(2)作为冲压成形的板材毛坯其相对厚度很小,当压应力作用时其抗失稳能力也相当差,因此在无抗失稳装置的这种情形下,自由状态下成功地完成冲压成形过程比较难。因此,以压应力作用为主的压缩类成形过程少于以拉应力作用为主的伸长类冲压成形过程。
(3)在冲压成形过程中,材料的屈服应力的数值不小于板材毛坯内应力。在该方面上,体积与冲压成形的差别相当大。因此,在冲压成形过程中变形区应力状态中的静水压力成分对变形抗力与成形极限的影响,已没有了在体积成形时的重要程度,在一些情形下,完全可以不用考虑到,即使有需要考虑的时候,它的处理方式也不相同。
(4)在冲压成形过程中,对于板材毛坯作用力模具产生的约束作用比较轻,不同于体积成形是靠与制件形状近似一样的型腔全面接触毛坯而完成的强制成形。在冲压成形过程中,在大部分形式下,板材毛坯都有一定程度的自由度,很多时候是唯有其中一个表面与模具接触,甚至在某些时候与模具接触板材两侧表面都有变形部分。在该种情况下,这部分毛坯的变形是用模具对其相邻部分作用外力来完成其控制作用的。比如,管胚端部的卷边成形与锥面与球面零件成形时的悬空部分都属于该情况。因为在力学与变形方面冲压成形具有上述一些特点,这导致冲压技术也产生了部分与体积成形不相同的特点。
因为在板材毛坯的表面不用施加很大的单位压力就可以让其成形,如此一来在冲压技术中有关模具刚度与强度的研究则不重要,相反的简易模具技术却发展了很多。因为一样原因,也使得用液体或气体压力成形的工艺方法得到了发展。