共查询到20条相似文献,搜索用时 109 毫秒
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逆向工程的特点可以最大限度地表现造型设计师的设计风格,该特点使逆向工程非常适合于覆盖件产品开发。针对摩托车外观覆盖件的特点,对车架模型的建立方法提出了看法,强调了在逆向建模中先建立模型特征线的优先性,总结了曲面重构的经验和规律,最后给出了具体开发实例。 相似文献
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微车生产关键之一,是驾驶室、车身覆盖件的成形工艺。汽车覆盖件是构成驾驶室和车身的异形体表面零件,它表面带有装饰性,如连贯的装饰棱线,筋条及装饰坑凹等都要求美观大方。覆盖件的材料由厚度0.8~1.2mm的08F或08Al的冷轧钢板冲压而 相似文献
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《Journal of Manufacturing Processes》2008,10(1):12-20
An experimental program of a novel wire manufacturing process known as dieless drawing has been conducted. The process has the capability to effect a reduction in the diameter of a wire without the use of conventional wire drawing dies. Reduction in diameter is achieved by heating the wire, which is mechanically loaded parallel to its longitudinal axis, to a temperature that initiates plastic deformation. Both mathematical and finite element (FE) modeling of the process have been undertaken. An analysis of the wire deformation is presented and discussed. The maximum reduction in diameter achieved, effect of drawing velocity, temperature, and uniformity of resulting wire diameter are investigated. The mechanics and operational features of the experimental machine manufactured to facilitate the experimental program of dieless drawing are described. The mathematical model presented can be used to describe the occurrence of deformation during the process. This model has been validated by experiments carried out on the wire drawing machine. The primary observation from the experimental program was that uniformity of wire diameter after dieless drawing decreased with an increase in reduction ratio. Results obtained from the experimental work confirm that a complicated interdependence of the process parameters exists during the dieless drawing process. 相似文献
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Part 1 of this series of papers presents an analytical model for a multi-nose tube hydroforming process based on a mechanistic approach. In this process, the tube is surrounded by a number of evenly distributed circular dies. The model was established based on equilibrium conditions, yielding criteria, geometrical relationships, and a volume constancy condition. The system of equations was derived and solved for various process parameters. The model validation was performed using finite element analysis and experiments. The model has the ability to predict process parameters such as stresses, strains, internal pressure, geometry variables, and thinning rate distribution. The model could be applied to regular planar tube hydroforming of polygonal shapes such as square, pentagon, or octagon. Details for establishing governing relationships for polygonal shape hydroforming from the multi-nose analytical model are given in Part 2 of this series of papers. 相似文献
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《Journal of Manufacturing Processes》2014,16(2):257-263
Three-dimensional (3D) porous structures facilitating cell attachment, growth, and proliferation is critical to tissue engineering applications. Traditional solid freeform fabrication (SFF) methods have limited capabilities in the fabrication of high resolution micro-scale features to implement advanced biomedical functions. In this work, we present a hybrid scaffold fabrication approach by integrating electrohydrodynamic (EHD) printing technology with extrusion deposition together to fabricate hierarchical 3D scaffolds with well controlled structures at both macro and micro scale. We developed a hybrid fabrication platform and a robust fabrication process to achieve 3D hierarchical structures. The melting extrusion by pneumatic pressure was used to fabricate 3D scaffolds with filaments dimension of hundreds of microns using thermoplastic biopolymer polycaprolactone (PCL). An electrohydrodynamic (EHD) melt jet plotting process was developed to fabricate micro-scale features on the scaffolds with sub-10 μm resolution, which has great potential in advanced biomedical applications, such as cell alignment and cell guidance. 相似文献
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通过对零件成形工艺的分析 ,确定了合理的冲压方案 ,减少了模具的投入。介绍了模具的结构特点及工作过程 ,具有一定的参考价值 相似文献
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此文在分析拉深件零件特点的基础上,对其特征的信息构成进行了研究。采用成组技术,提出了一种特征编码的信息表达方式。该方式不仅可以方便地实现零件的自动工艺设计,而且还可实现零件的成组工艺、模具的成组设计,从而缩短产品的生产周期,降低成本。 相似文献
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《Journal of Manufacturing Processes》2014,16(3):379-390
Creepage, a typical phenomenon in the hemming process, can be defined as undesired roll-in of the panel at the bending line. Creepage also reduces the final panel width and makes the hemming radius larger. In this study, experimental observations are reported, and a finite element model, based on the LS-DYNA® two dimensional plane strain solid formulation, is utilized to study the mechanics of how the hem flange bends and folds during the hemming process. A novel hemming process incorporating a counteraction force is proposed in order to prevent the creepage phenomenon during the hemming process. An experimental hemming tool was designed according to this concept, and optimization of the tooling geometry was carried out utilizing the finite element model. An experimental study was conducted to confirm that the new hemming process can prevent creep be employed to help retain a sharp radius during flanging operation. 相似文献
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根据楔横轧模具孔型及其加工成形的特点,对楔横轧模具大面积大螺距楔形提出了一种简单高效的铣削加工方法,并设计制造了楔横轧轧辊模具孔型加工专用机床——SDM机床。新设计的SDM机床投资小,可以加工直径为φ620 mm~φ1000mm的轧辊模具,加工导程最大可达469 mm,加工周期短,成本低,且大大降低了工人劳动强度。 相似文献
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通过使用可移式轧辊模具 ,成功地利用一副模具轧制出了形状相似、仅局部尺寸不同的多种规格的阶梯轴 ,使楔横轧工艺在规格较多、批量较小的轴类零件毛坯成形中得到了应用 ,楔横轧技术得到了进一步发展和推广。 相似文献
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通过对压套零件的冲压工艺分析,省去外缘修边工序。外缘翻边时,利用板料的塑性平面各向异性在拉深件凸缘处产生的凸耳,翻边后形成图纸要求的凸、凹R50mm的外形尺寸,成功地用四套模具生产出摩托车离合器压套零件,降低了模具成本,提高了材料利用率。 相似文献