共查询到20条相似文献,搜索用时 140 毫秒
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1.无模多点成形技术的基本原理与技术特点 无模多点成形技术是由吉林大学李明哲教授在日本做博士后研究工作期间命名的一项金属板材三维曲面成形的先进制造技术。其基本原理是利用一系列规则排列的、高度可调的基本体(冲头),通过对各个基本体的实时控制,构造出所需形状的成形面,取代传统 相似文献
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板料柔性成形是基于产品的数字化信息,由产品的三维CAD模型直接驱动,通过高度可调的基本体构成包络面,实现三维曲面零件成形的技术。典型的板料柔性成形方法是增量成形与多点成形。增量成形通过一个成形工具头沿x、y轴方向的运动及z轴方向的进给,逐层形成零件的三维包络面,从而实现板料的渐进成形;多点成形的核心是规则排列的基本体阵列,通过控制基本体z方向的位置坐标使其构成所需包络面,进行板料快速成形。介绍了以数控多点柔性成形新工艺进行新产品开发试制的应用。 相似文献
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多点冲模点销高度调整方法 总被引:1,自引:0,他引:1
石玉祥 《机械工人(热加工)》2000,(4):34-34
多点冲模是一种新颖的以三维曲面成形为目的的板料柔性成形方法。尤其适于多品种、小批量生产。其原理结构和成形中的起皱问题已有所探讨。本文就多点冲模关键问题之一——点体群(销子)高度控制问题作一论述。 相似文献
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自由曲面工件多点连续成形方法 总被引:7,自引:1,他引:6
为了实现自由曲面工件的高效率、低成本制造,分析与比较常用的柔性成形方法;从成形过程的连续性考虑,将柔性成形分为分段成形与连续成形;从变形区大小考虑,又划分为点成形、面成形与线成形等不同类型。比较不同成形方式的优点与缺点,指出自由曲面工件的高质量、高效率成形是亟待解决的技术难题。提出基于连续线成形方法的自由曲面工件高效、柔性成形思路;并提出采用多点调整式柔性辊的多点连续成形技术方案;探讨多点连续成形技术的基本原理、关键技术及主要特点。运用具有多个控制点的挠性轴设计出可弯曲、可调整的柔性辊,开发出多点卷板成形试验装置。多种三维曲面板类件的连续成形试验结果表明,多点连续成形技术能够解决自由曲面工件的高效加工难题。 相似文献
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Principles and apparatus of multi-point forming for sheet metal 总被引:2,自引:2,他引:0
Chunguo Liu Mingzhe Li Wenzhi Fu 《The International Journal of Advanced Manufacturing Technology》2008,35(11-12):1227-1233
As a flexible forming method for sheet metal part, multi-point forming (MPF) technology is discussed in the paper. It employs two reconfigurable element groups to approximate the continuous upper and lower solid dies. With the technique, rapid fabrication of 3D sheet metal part is realized. The principles of multi-point die forming (MPDF) and multi-point press forming (MPPF) are described and then the rules to determine the size of the element are given. For any spatial shape surface to be formed, all elements’ height can be calculated through the contacting point calculation equation. On the computer control, the shape of the two element groups can be adjusted by serial adjusting mode or parallel adjusting mode. MPDF apparatus that includes CAD software, computer control system, two element groups, hydraulic press and laser CMM is developed. Following the given MPF procedure, 3D sheet metal part was formed without failure. Due to the rapid change characteristics of the two element groups, several special MPF forming techniques that are impossible in conventional sheet forming have been investigated in detail. By flexible blank holder technique, thin sheet MPDF is realized. With sectional MPF, large size sheet would be formed on small scale MPF apparatus. Through closed loop MPF, spring-back would be compensated cycle by cycle, and large deformation part is obtained with incremental MPDF successfully. 相似文献
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多点成形压力机及成形工艺的最新进展 总被引:4,自引:0,他引:4
多点成形技术是金属板材三维曲面成形的新技术 ,与传统的整体模具板材成形工艺相比 ,多点成形压力机有许多优点 ,可以实现三维板类件既经济又快速的柔性成形。本文介绍了多点成形压力机系列规格参数、设备构成原理及其成形工艺。重点论述了几个现有的多点成形压力机的技术参数、调形方式的重大改进及多点成形技术应用领域的不断扩大。 相似文献
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Formability analysis on the process of multi-point forming for titanium alloy retiary sheet 总被引:2,自引:2,他引:0
Tan Fuxing Li Mingzhe Cai Zhongyi Li Xiangji 《The International Journal of Advanced Manufacturing Technology》2009,41(11-12):1059-1065
The multi-point forming (MPF) process of spherical surface parts of titanium alloy retiary sheet and titanium alloy sheet metal with different thickness and curvature radius was simulated by an explicit finite element software. Contradistinctive analysis between retiary sheet and sheet metal forming parts with different modes were done. The simulation results show that under the same forming conditions, titanium alloy retiary sheet is not easy to wrinkle and springback, whereas it is easy to form. The reason for differences in the formability of above-mentioned sheet metal is also analyzed. A non-wrinkling limited graph and a fracture critical graph for spherical surface parts of retiary metal sheet and metal sheet were obtained. Finally a forming test of titanium alloy cranial prosthesis was done in MPF press. Testing results indicate the customized 3D curved surface of prosthesis can be adequately shaped and the forming quality was guaranteed. 相似文献
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Jian-Jun Chen Wei Liu Ming-Zhe Li Cheng-Tao Wang 《The International Journal of Advanced Manufacturing Technology》2006,27(11-12):1148-1152
Based on multi-point forming (MPF) technology, a novel digital manufacturing method of cranial titanium plates for the repair of skull defects is developed in this paper. First, a 3D triangular mesh model of the skull is constructed from a CT data set. Then, a non-uniform rational B-splines-format (NURBS-format) patch surface is obtained by surface interpolation based on the skull polygon model. Finally, the patch surface model is input to MPF CAD/CAM software and the cranial titanium prosthesis is deformed by an MPF press. The method has many new features compared with other means. Implementing medical image processing and MPF technology, the method can remarkably shorten the production cycle of titanium cranioplasty, as well as offer improved fitting precision. About 20 practical applications have been finished, which prove the feasibility and efficiency of the method. 相似文献
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Heli Peng Mingzhe Li Chunguo Liu Junhui Cao 《The International Journal of Advanced Manufacturing Technology》2013,67(9-12):2811-2817
The multi-point forming (MPF) process of polycarbonate (PC) sheet is introduced briefly, geometrical relationship between objective surface and punch element is determined, and a simple calculation scheme of punch height is developed. Numerical simulations of spherical and saddle-shaped parts are carried out by dynamic explicit finite element analysis; the effects of forming temperature, forming pressure, punch matrix, and punch radius on the forming quality are investigated, and the suitable forming parameters are determined. Then, the MPF experiments of PC sheet for spherical and saddle-shaped parts based on the forming parameters are done, and the comparisons of shape error between experimental parts and object surfaces are carried out. Consequently, the PC products have good shape accuracy, which confirms that MPF used for forming PC sheet is feasible and the forming parameters obtained by numerical simulation are sensible. 相似文献
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Numerical investigation of multi-point forming process for sheet metal: wrinkling, dimpling and springback 总被引:2,自引:2,他引:0
Zhong-Yi Cai Shao-Hui Wang Ming-Zhe Li 《The International Journal of Advanced Manufacturing Technology》2008,37(9-10):927-936
Multi-point forming (MPF) is a new flexible technique for manufacturing three-dimensional sheet metal parts. In this procedure, a pair of opposed matrices of punch elements substitute for the conventional fixed shape die sets, and the sheet metal can be formed rapidly between the matrices. Extensive numerical simulations of the processes for forming spherical and saddle-shaped parts were carried out by dynamic explicit finite element analysis. The contacting process between sheet metal and punch elements in MPF was investigated, and the variations of forming force with respect to the tool travel were analyzed. The wrinkling processes were simulated, and the MPF limit curves without wrinkles for spherical and saddle-shaped parts were obtained. Dimple is a particular defect in MPF, through the comparison of the thickness strains calculated by solid FE and shell FE, the finite elements appropriate for the numerical analysis of dimpling were detected, and the limit forming force without dimples was determined. Springback processes of MPF were simulated based on explicit-implicit algorithm. The springbacks and their distributions under different conditions were investigated. 相似文献
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针对目前的一些中小型模具制造企业仍停留在运用系统提供的基本功能单纯的进行几何造型设计的阶段,以及对三维CAD技术应用不广、应用水平不高、二次开发能力不强的现状,为此在模具设计中采用三维CAD软件UG、vc++软件、以及Access数据库软件,开发出了能够对吸塑模具抽芯机构进行快速设计的三维CAD系统。该系统通过UG/Open GRIP与UG/Open API的程序之间地相互调用实现了抽芯机构的参数化设计,大大提高了设计效率,并通过抽芯机构的运动仿真避免了运动过程中的干涉,确保吸塑件的顺利脱膜,达到了预想的设计效果。 相似文献
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在以汽车工业为代表的批量生产制造业中,工件表面微观结构的二维测量迄今仍处于主流地位,这主要是由所采用的工艺和已建立的完善的评定体系决定的。但近几年,随着激光造型等新工艺在一些重要工序中的应用日趋增多,表面微观结构的三维测量也进入了实用阶段。本文通过实例对其进行了描述,并就相关的评定参数做了介绍。 相似文献
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