二工位级进模的设计

根据工件的工艺特点,确定采用二工位冲裁级进模冲压工件;阐述了工件的冲裁排样,模具冲裁力和压力中心的计算,压力机的选择,凸、凹模刃口尺寸计算及其结构设计,模具总体结构及工作过程。     

T2紫铜箔材的U型弯曲变形

设计了箔板U型弯曲试验方案,使用不同凹模槽宽尺寸和圆角半径的微型模具,在三思微型试验机上完成了试验,分析了模具几何尺寸、箔板厚度等对箔板U型弯曲变形中冲头载荷、回弹以及表面质量的影响。研究结果表明,槽宽尺寸或圆角半径减小时,最大冲头载荷显著增加,且冲头载荷上升和下降速率都明显增大;对比两种不同厚度箔板的冲头载荷显示,冲头载荷减小速率明显快于横截面面积的减小速率,说明产生了明显的尺寸效应;另外,圆角半径或板厚减小,导致回弹角度增大,成形件精度降低;虽然成形件表面比较平整,但侧面出现划痕提示需要提高模具表面质量和采取润滑措施。以上研究结果对指导箔板微成形工艺设计具有重要意义。     

基于图论的高精度级进模跳步排样优化算法

跳步排样是高精度级进模ＣＡＤ中的重要组成部分。提出一种基于图论的跳步排样优化算法。利用工艺规则，通过起始关键点的获取，最少工步数的确定，到排样的优化，来保证级进模的工作精度。     

模具CAD／CAM系统中的工艺设计

在综合叙述级进模ＣＡＤ系统总体结构的基础上，详细论述了冲裁工艺安排的技术要点，包括数据结构，图论算法，推理规则以及交互界面。     

Tool wear investigation on the precision progressive die for the IC dam-bar cutting process

The IC dam-bar cutting process is conducted with the precision progressive shearing die, while the cutting quality of the sheared product is subject to the wear status of the punch. The main objective of this study was to explore the relationship between the burnished band of the sheared surface and the wear of the shearing punch in the thin sheet cutting process. Firstly, the Taguchi method was applied to scheme the dam-bar cutting experiments. Two different HSS punches, ASP60 and SKH9, were used to punch the simulated leads made of the phosphor bronze C5191R-H. The variance analysis and confirmation experiments were also executed to verify the analytical results. The experimental data was collected to establish the punch wear estimated model. Secondly, a concept of an equivalent wear length of the punch flank was introduced to examine the wear of the punch flank, and the gravimetric wear rate was also calculated to examine the amount of the punch wear due to weight loss. Finally, the estimated model of the gravimetric wear rate through the burnished area of the dam-bar sheared surface was constructed. One can directly determine the status of the cutting punch depending on the size of the burnished band, as a basis for tool changing or regrinding.     

浮动凹模径向挤压力经验计算法

以双浮动凹模冷挤压十字轴为例,通过分析径向挤压时金属载荷的分布及关系,建立了理想刚塑性计算模型;同时以传统的正挤压模型和计算方法为基础,分割十字轴计算模型并建立了当量挤压力的受力模型,得到了一种径向挤压力的经验计算方法,计算出十字轴径向挤压时凸模的轴向载荷和凹模的合模力。将该方法推广使用到三叉轴和双叉轴的径向挤压,利用DEFORM-3D数值模拟对计算结果进行验证,确定了该计算方法的正确性和实用性。     

基于MasterCAM的电吹风外壳凸模数控加工

为了提高模具加工的质量和效率,以电吹风外壳凸模为例,介绍了用MasterCAM软件进行数控编程的基本方法,重点论述了电吹风外壳凸模加工工艺方案的合理性,并对电吹风外壳凸模进行了仿真模拟加工。     

The design of a semi-additive manufacturing shape using metal 3D printing for a partially strengthened mold based on a high-alloy tool steel powder

In this paper, describe the fabrication of high strength punch molds that can be applied to ultra-high strength sheet materials after processing. A method for improving the strength of the punching die by additive manufacturing (AM) of a high strength powder material using a metal 3D printer was proposed. Furthermore, a semi-additive technique was proposed to increase the punch strength through partial AM of specific parts of the punch that require high strength. A preprocessing process for predicting the semi-additive shape for the punch function portion is proposed for application of the AM technology of a metal 3D printer to this semi-additive technique. The preprocessing for determining the semi-additive shape consists of the predicting step of the punch strength based on the shear process of the sheet material, analyzing step the stress distribution of the punch, defining step the semi-additive range, designing step the semi-additive shape, and verifying step the additive interface strength. Based on this simulation, the range of shapes for the semi-additive was 1.21 mm and 2.62 mm for sheet material CP1180 and 1.3 mm and 3.2 mm for sheet material 22MnB5. The shape and range determined in the simulation process defines a semi-additive area (volume) for the 3D printing AM technique using a high-strength powder material, and a semi-additive punch was manufactured according to the defined area. The semi-additive punch (HWS powder material) fabricated in this study was performed a durability test for validity verification in the piercing process of high-strength sheet material (CR980). This validation test compared the state of the punch after 1000 piercing processes with a typical cold piercing punch (SKD11 solid material). From this test, the feasibility of the semi-additive punch was confirmed by showing a similar state of scratches and abrasion from the two punches. The simulation analysis processor for the additive shape and the additive range prediction for the semi-additive punch manufacturing presented in this paper can be useful for the additive manufacture of cutting and trimming punch mold.

     

一种多功能箱包冲铆机的研制

一种超市购物袋的冲铆加工,采用传统铆钉机单只铆钉逐个冲铆,不易控制铆接位置且容易发生安全事故。根据客户要求,研制了一种多功能箱包冲铆机,一次能进行多点冲铆,更换模具能实现冲孔和铆接两种功能,由模具保证铆接品质,通过更换模具可实现不同规格产品的冲铆,比传统冲铆方式更安全,品质更可靠,但效率还有待提高。     

变径段的设计与制造

介绍了反向曲线变径段的设计和制造程序，总结出在标准椭圆封头中心开孔的两个经验公式，利用标准椭圆封头上胎具，二次冲压成形，缩短了制造周期，大大降低了制造成本。     

侧向槽粉末制品压制成型工艺

叙述了YAN79Z-B型模架全自动干粉成型液压机压制工艺的设计，在压制粉末冶金侧向槽过程中，阴模与浮动冲上升到设定位置，送粉器前移对阴模腔内充满粉料后，上冲下行到阴模内向下压制时，利用阴模与浮动冲的同步浮动，压制到终了位置产品成型，然后阴模拉下，浮动冲微升推出产品，实现了侧向槽产品国产化，自动化生产。     

基于PDCA理论的模具制造车间质量管理

为了延长凸模的使用寿命,运用全面质量管理的PDCA循环法,针对凸模质量失效问题进行了分析,并以T型冲头为例,对冲头加工的热处理工艺和机加工工艺进行改进,提高了冲头产品的硬度、韧性和耐磨性,最后以应用实例证明了应用PDCA法对冲模进行质量管理能够为企业取得良好的经济效益。     

单泵多马达液压变速器组合机构的设计与研究

针对单泵单马达液压变速器手动变量传动比不准确的问题,提出了单泵多马达液压变速器。通过设计单泵多马达液压变速器的传动回路,得出多马达中各个子马达之间工作方式的组合可以使变速器传动比有多级变化。通过设计组合机构来代替换向阀,使单泵多马达液压变速器更加集成化,效率更高。对组合机构在两个位置之间的切换过程和不同位置处的受力进行分析和计算,结果表明:为避免在切换过程中出现泵、马达进出油路闭死,腰形通道两个圆心之间的角度必须大于某一值;组合机构的中盘受颠覆力矩的作用,其厚度需大于某一最小值,才能避免在壳体内卡死。为单泵多马达液压变速器整体结构的设计奠定了理论基础。     

激光诱导空化微孔冲裁试验研究

针对微尺度下金属箔模具冲孔存在模具挤压磨损、对中困难,激光打孔存在烧蚀、吸收层无法补偿等问题,提出通过激光诱导空泡对金属箔进行加载来实现冲裁小孔的方法。研究了不同激光焦点位置(H=0~4 mm)、激光能量(E=10.3~50.8 mJ)和铜箔厚度(T=20~70μm)对铜箔冲孔的影响,发现激光焦点位置影响明显,当铜箔变形平均深度达到147.0μm后,铜箔发生剪切断裂,可实现冲裁,并且制备的小孔边缘正表面无烧蚀、毛边、裂纹和卷边等缺陷。同时,利用高速摄影仪对激光诱导空化微孔冲裁过程进行研究,结果表明激光诱导空化微孔冲裁过程是激光等离子体冲击波、空泡溃灭冲击波和微射流共同加载的过程。     

灯座三角盘硬质合金多工位级进模设计

分析了灯座三角盘的工艺特点,确定了排样方案及模具的结构,采用了快换式、分体式凸模结构和防误送的检测装置,冲压制件精度高,模具使用寿命高,便于维修和维护。     

蠕变现象的小冲杆试验研究--蠕变应力分析

主要阐述根据小冲杆试样实测中心挠度求蠕变应力的问题。包括：借助“表征”概念，将试样中心点视为整片试样的表征点；利用压力容器薄膜理论之力平衡关系确定特定时间状态下试样中心区域的应力状态，推导小冲杆试样中心点的蠕变应力估算公式；按该估算公式处理12CrlMoV钢在特定试验条件下获得的小冲杆变试验数据，并对比由此求得的蠕变应力－时间关系与有限元计算的同类结果，根据两者的一致程度判定应力计算模型和工程估算公式的可信度。最后，文章还对具体如何确定特定小冲杆试验之表征蠕变应力值给出了建议。     

Development of an automated progressive design system with multiple processes (piercing, bending, and deep drawing) for manufacturing products

This paper describes the research work involved in developing an automated progressive design system with multiple processes such as piercing, bending, and deep drawing for manufacturing products. This approach to make a progressive, flexible working system is based on knowledge-based rules. The knowledge required for this system is formulated from plasticity theories, experimental results, and the empirical knowledge of field experts. The system consists of three main modules: shape treatment, strip layout, and die layout modules. The system is founded on knowledge-based rules and is designed in consideration of several factors, such as the material and thickness of a product, the piercing, bending and deep drawing sequence, and the complexities of blank geometry and punch profiles. The system then generates the strip layout drawing for an automobile product. The die layout module carries out the die design for each process from the results of the strip layout module. The results obtained using the modules enable the designers of manufacturing products with multiple processes to be more efficient in this field.     

基于转矩平衡和模拟退火的级进模压力中心优化研究

针对级进模压力中心的求解及优化,提出应用转矩平衡原理建立带料压力中心求解模型的方法,推导出了压力中心与滑块中心偏离值、滑块中心两侧转矩偏移等量随时间变化的计算公式。在中心偏移优化法的基础上,提出了一种使滑块中心两侧转矩偏移最小的优化方法,建立了相应的目标函数与约束函数。结合有限元模拟技术,计算了各工序中凸模的冲压力随时间的变化情况,并使用模拟退火算法,迭代求解了最优带料压力中心偏移值。以壳形电子零件的级进模为例,与理论计算作比较,验证了上述方法的有效性。     

30CrMnSiNi2A长锥形深孔件成形技术研究

通过分析超高强度钢深孔筒形件的精密成形工艺,指出其工序繁杂以及冲头寿命短的原因。并针对实际的成形条件设计了一种新型冲头,使得冲头工作条件大大改善,冲头寿命大大提高。此外,使得成形工序大大缩减、节约了能源、降低了生产成本,解决了超高强度钢制薄壁壳体制造过程中的关键技术难题,为宇航、兵器等行业普遍采用的这类薄壁壳体零件的研究和生产提供了一种实用、高效、经济、可靠的精密成形工艺。     

Algorithm for automatic undercut recognition and lifter design

When having internal undercut in the ejection direction, the finished plastic product cannot be directly removed from the mold. Through lifter design, during the ejection process, the lifter can eject products in the upward direction and make lateral movements to successfully leave the undercut location to part from the mold. Under the framework of CAD software, this study developed the undercut feature recognition, integrated the mold design, and automated lifter production. Based on the geometric relationship of the internal undercut surface, edge, and point of the product model, this study summarized a set of recognition rules. Through computer programming calculation and judgment, the proposed method can automatically recognize undercuts to reduce the labeling time at the conceptual design stage and record the undercut width and length in feature parameters. At the mold design stage, through the acquisition and calculation of its parameters, it can automatically produce a suitable lifter during the architecture of the web-based mold design navigation process. Through standardized design process, it can reduce 90 % of mouse clicks and design time to guide users to quickly complete the design, while reducing design errors to improve working efficiency by the automatic integration function.