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手机充电器注塑模具设计[抽芯]【含全套11张CAD图纸和毕业论文】【优秀资料】

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手机充电器注塑模具[抽芯]【含全套CAD图纸+毕业论文】【优秀资料】.rar

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Fabrication of piezoelectric ceramicpolymer composites by injection molding.pdf---(点击预览)

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图纸共11张:
A0-整体图.dwg
A0-装配图.dwg
A1-凹模.dwg
A1-支撑板.dwg
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A2-凸模.dwg
A2-型芯.dwg
A3-充电器外形.dwg
A4-定位圈.dwg
A4-浇口套.dwg

摘要

摘要
分析了手机充电器外壳的工艺特点，介绍了手机充电器外壳上盖注射模结构及模具的工作过程。重点介绍了手机充电器外壳注射模结构的设计
方法。分析和阐述了模具型芯零件及各标准件的选材、热处理工艺，手机充电器外壳的塑件的结构要素，塑件的尺寸公差和精度的选择，塑件
的体积和质量的计算方法以及注射机的选择和校核。此手机充电器外壳注射模设计的结构特点是点浇口形式的单分型面的注射模。该模具结构
设计巧妙，操作方便，使用寿命长，塑件达到技术要求。
关键词：手机充电器外壳；注射模；型芯；型腔
Abstract
Has analyzed the handset battery charger outer covering craft characteristic, introduced the handset battery charger outer
covering top head injection mold structure and the mold work process. Introduced the handset battery charger outer covering
injection mold structure design method with emphasis. Analyzed and elaborated the mold core components selection, the heat
treatment craft, the handset battery charger outer covering model the member, model the size common difference and the
precision choice, model a volume and the quality computational method. This handset battery charger outer covering injection
mold designs the unique feature is the runner form three minute profiles injection molds, is lateral pulls out the core
injection mold. After production confirmation, this mold structural design ingenious, the ease of operation, the service life
is long, models to achieve the specification.
Key words: handset battery charger outer；covering injection mold；slide；core.

目录
第1章绪论 - 1 -
1.1 模具工业在国民经济中的地位 - 1 -
2.2 国模具技术的现状及发展趋势 - 1 -
第2章塑件工艺分析 - 3 -
2.1 塑件的结构要素 - 3 -
2.1.1 ABS的使用性能 - 3 -
2.1.2 ABS材料的成形特点 - 3 -
2.1.3 ABS的成型工艺 - 4 -
2.2 注射成型工艺 - 4 -
第3章塑件几何形状的设计 - 6 -
3.1 塑件几何形状的设计 - 6 -
3.1.1 脱模斜度 - 6 -
3.1.2 加强筋 - 6 -
3.1.3 塑件的圆角 - 7 -
3.1.4 塑件的壁厚 - 7 -
3.1.5 孔 - 7 -
3.1.6 支承面 - 7 -
3.2 塑件尺寸公差与精度 - 7 -
第4章分型面及型腔数目的确定 - 9 -
4.1 型腔分型面及型腔数目 - 9 -
4.2 型腔、型芯的结构 - 9 -
4.2.1 型腔的结构设计 - 10 -
4.2.2 型芯的结构设计 - 10 -
第5章注射机的选取和校核 - 11 -
5.1 根据型腔数选择注射机 - 11 -
5.1.1 根据塑件形状估算其体积和重量 - 11 -
5.1.2 选择注射机 - 11 -
5.2 校核注射机有关工艺参数 - 12 -
5.2.1 注射量的校核 - 12 -
5.2.2 锁模力的校核 - 12 -
5.2.3 开模行程的校核 - 13 -
第6章成型零件的设计 - 13 -
6.1 成型零件的结构设计 - 13 -
6.1.1 凹模的结构设计 - 14 -
6.1.2凸模和型芯的结构设计 - 14 -
6.2 成型零件工作尺寸的计算 - 14 -
6.2.1凹模与凸模工作尺寸 - 15 -
6.2.2凹模与凸模尺寸计算 - 15 -
6.2.3型腔的强度设计 - 16 -
第7章浇注系统的设计 - 17 -
7.1 主浇道的设计 - 17 -
7.2 分浇道的设计 - 17 -
7.3 浇口的设计 - 18 -
7.4 冷料穴的设计 - 18 -
第8章结构零件的设计 - 19 -
8.1 脱模机构的设计 - 19 -
8.1.1 机构的设计原则 - 19 -
8.1.2 脱模机构分类 - 19 -
8.2 脱模机构的导向与复位 - 20 -
8.2.1导向零件 - 20 -
8.2.2 复位零件 - 20 -
第9章塑料模具钢的选用 - 21 -
9.1 塑料模具材料应具有的性能 - 21 -
9.2 模具选材原则 - 21 -
第10章模具结构及其工作过程 - 24 -
9.1 模架的选择 - 24 -
9.2 模具工作过程 - 24 -
结论 - 26 -
致谢 - 27 -
参考文献 - 28 -

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内容简介：: FABRICATION OF PIEZOELECTRIC CERAMlClPOLYMER COMPOSITES BY INJECTION MOLDING. Leslie J. Bowen and Kenneth W. French, Materials Systems Inc. 53 Hillcrest Road, Concord, MA 01742 Abstract Research at the Materials Research Laboratory, Pennsylvania State University has demonstrated the potential for improving hydrophone performance using piezoelectric ceramic/polymer composites. As part of an ONR-funded initiative to develop cost-effective manufacturing technology for these composites, Materials Systems is pursuing an injection molding ceramic fabrication approach. This paper briefly overviews key features of the ceramic injection molding process, then describes the approach and methodology being used to fabricate PZT ceramic/polymer composites. Properties and applications of injection molded PZT ceramics are compared with conventionally processed material. Introduction Piezoelectric ceramic/polymer composites offer design versatility and performance advantages over both single phase ceramic and polymer piezoelectric materials in both sensing and actuating applications. These composites have found use in high resolution medical ultrasound as well as developmental Navy applications. Many composite configurations have been constructed and evaluated on a laboratory scale over the past thirteen years. One of the most successful combinations, designated 1-3 composite in Newnhams notation l 1, has a one-dimensionally connected ceramic phase (PZT fibers) contained within a three-dimensionally connected organic polymer phase. Hydrophone figures of merit for this composite can be made over 10,000 times greater than those of solid PZT ceramic by appropriately selecting the phase characteristics and composite structure. The Penn State composites were fabricated l by hand-aligning extruded PZT ceramic rods in a jig and encapsulating in epoxy resin, followed by slicing to the appropriate thickness and poling the ceramic. Aside from demonstrating the performance advantages of this material, the Penn State work highlighted the difficulties involved in fabricating 1-3 composites on a large scale, or even for prototype purposes. These are: 11 The requirement to align and support large numbers of PZT fibers during encapsulation by the polymer. 2) The high incidence of dielectric breakdown during poling arising from the significant probability of encountering one or more defective fibers in a typical large array. Over the past five years several attempts have been made to simplify the assembly process for 1-3 transducers with the intention of improving manufacturing viability and lowering the material cost. Early attempts involved dicing solid blocks of PZT ceramic into the desired configuration and back-filling the spaces with a polymer phase. This technique has found wide acceptance in the medical ultrasound industry for manufacturing high frequency transducers 2. More recently, Fiber Materials Corp. has demonstrated the applicability of its weaving technology for fiber-reinforced composites to the assembly of piezoelectric composites 31. Another exploratory technique involves replicating porous fabrics having the appropriate connectivity 41. For extremely fine scale composites, fibers having diameters in the order of 25 to 100 pn and aspect ratios in excess of five are required to meet device performance objectives. As a result, these difficulties are compounded by the additional challenge of forming and handling extremely fine fibers in large quantities without defects. Recently, researchers at Siemens Corp. have shown that very fine scale composites can be produced by a fugitive mold technique. However, this method requires fabricating a new mold for every part 51. This paper describes a new approach to piezoelectric composite fabrication, viz: Ceramic injection molding. Ceramic injection molding is a cost- effective fabrication approach for both Navy piezoelectric ceramic/polymer composites and for the fabrication of ultrafine scale piezoelectric composites, such as those required for high frequency medical ultrasound and nondestructive evaluation. The injection molding process overcomes the difficulty of assembling oriented ceramic fibers into composite transducers by net-shape preforming ceramic fiber arrays. Aside from this advantage, the process makes possible the construction of composite transducers having more complex ceramic element geometries than those previously envisioned, leading to greater design flexibility for improved acoustic impedance matching and lateral mode cancellation. Process Descriotion Injection molding is widely used in the plastics industry as a means for rapid mass production of complex shapes at low cost. Its application to ceramics has been most successful for small cross- section shapes, e.g. thread guides, and large, complex shapes which do not require sintering to high density, such as turbine blade casting inserts. More recently, the process has been investigated as a production technology for heat-engine turbine components 6,71. The injection molding process used for PZT molding is shown schematically in Figure 1. By injecting a hot thermoplastic mixture of ceramic powder and organic binder into a cooled mold, complex shapes can be formed with the ease and rapidity normally associated with plastics molding. Precautions, such as hard-facing the metal contact surfaces, are important to minimize metallic contamination from the compounding and molding machinery. For ceramics, the binder must be removed nondestructively, necessitating high solids loading, careful control of the binder removal Powder Process i ng -r- 4 CERAMIC PREFORM Organic Binder - - - - I Granulate I - - - - - - PREFORM LAY-UP TO FORM LARGER ARRAYS -_Lu-i_- 1-1 and apply electrodes Figure 1 : Injection Molding Process Route. process, and proper fixturing. Once the binder is removed, the subsequent firing, poling and epoxy encapsulation processes are similar to those used for conventional PZTipolymer composites 11 I . Thus, the process offers the following advantages over alternative fabrication routes: Complex, near net-shape capability for handling many fibers simultaneously; rapid throughput (typically seconds per part); compatibility with statistical process control; low material waste; flexibility with respect to transducer design (allows variation in PZT element spacing and shape); and low cost in moderate to high volumes. In general, because of the high initial tooling cost, the ceramics injection molding process is best applied to complex-shaped components which require low cost in high volumes. Comoosite Fabrication and Evaluation The approach taken to fabricate 1-3 piezoelectric composites is shown in Figure 2a, which illustrates a PZT ceramic preform concept in which fiber positioning is achieved using a co-molded integral ceramic base. After polymer encapsulation the ceramic base is removed by grinding. Aside from easlng the handling of many fibers, this preform approach allows broad latitude in the selection of piezoelectric ceramic element geometry for composite performance optimization. Tool design is important for successful injection molding of piezoelectric composites. The approach shown in Figure 2b uses shaped tool inserts to allow changes in part design without incurring excessive retooling costs. Figure 2c shows how individual preforms are configured to form larger arrays. Figure 2a: Preform Configuration (Approx. 400 ceramic elements) REMOVABLE INSERT : CAVITY TOOL BODY U * S P R U E Figure 2b: Injection Molding Tool Configuration Figure 2c: Large Area Composite Arrays made from Preforms Figure 2: Preform Approach to Composite Fabrication. In practice, material and molding parameters must be optimized and integrated with injection molding tool design to realize intact preform ejection after molding. Key parameters include: PZT/binder ratio, PZT element diameter and taper, PZT base thickness, tool surface finish, and the molded part ejection mechanism design. In order to evaluate these process parameters without incurring excessive tool cost, a tool design having only two rows of 19 PZT elements each has been adopted for experimental purposes. Each row contains elements having three taper angles (0, 1 and 2 degrees) and two diameters (0.5 and lmm). To accommodate molding shrinkage, the size of the preform is maintained at 5Ox50mm to minimize the possibility of shearing off the outermost fibers during the cooling portion of the molding cycle. Figure 3: Injection Molded 1-3 Composite Preforms. 161 Figure 3 shows green ceramic preforms fabricated using this tool configuration. Note that all of the PZT elements ejected intact after molding, including those having no longitudinal tapering to facilitate ejection. Slow heating in air has been found to be a suitable method for organic binder removal. Finally, the burned-out preforms are sintered in a PbO- rich atmosphere to 97-98% of the theoretical density. No problems have been encountered with controlling the weight loss during sintering of these composite preforms, even for those fine-scale, high-surface area preforms which are intended for high frequency ultrasound. . .- . . -. . L. . Figure 4: Scanning Electron Micrographs of As-molded (Upper) and As-sintered (Lower) Surfaces of PZT Fibers. Figure 4 illustrates the surfaces of as-molded and as-sintered fibers, showing the presence of shallow fold lines approximately 10pm wide, which are characteristic of the injection molding process. The fibers exhibit minor grooving along their length due to ejection from the tool. Figure 5 shows the capability of near net-shape molding for fabricating very fine scale preforms; PZT element dimensions only 30pm wide have been demonstrated. The as-sintered surface of these elements indicates that the PZT ceramic microstructure is dense and uniform, consisting of equiaxed grains 2-3pm in diameter. Figure 5: Fine-scale 2-2 Composite formed by Near Net- shape Molding (Upper Micrograph). As-sintered Surface (Lower Micrograph). In order to demonstrate the lay-up approach for composite fabrication, composites of approximately 10 volume percent PZT-5H fibers and Spurrs epoxy resin were fabricated by epoxy encapsulating laid-up pairs of injection molded and sintered fiber rows followed by grinding away the PZT ceramic stock used to mold the composite preform. Figure 6 shows composite samples made from freshly-compounded PZT/binder mixture and from reused material. Recycling of the compounded and molded material appears to be entirely feasible and results in greatly enhanced material utilization. Table 1 compares the piezoelectric and dielectric properties of injection molded PZT ceramic specimens with those reported for pressed PZT-5H samples prepared by the powder manufacturer. When the sintering conditions are optimized for the PZT-5H formulation, the piezoelectric and dielectric properties are comparable for both materials. Since the donor- doped PZT-5H formulation is expected to be particularly sensitive to iron contamination from the injection molding equipment, the implication of these measurements is that such contamination is negligible in this injection molded PZT material. *Powder supplied by Morgan Matroc, Inc., Bedford, Ohio; Lot 105A. 162 Table 1 : Properties of Injection Molded Piezoelectric Ceramics. Specimen Relative Dielectric d33 TY Pe Permittivity Loss (1 kHz1 (pC/N) Die-Pressed 3584 0.01 8 745 Inj. Molded* 3588 0.01 8 755 *Aged 24 hours before measuremegt. *Poling conditions: 2.4kV/mm, 60 C, 2 minutes. Figure 6: Injection Molded PZT Fiber/Epoxy Resin Composites prepared by the Preform Lay-up Method. Summarv Ceramic injection molding has been shown to be a viable process for fabricating both PZT ceramics and piezoelectric ceramic/polymer transducers. The electrical properties of injection molded PZT ceramics are comparable with those prepared by conventional powder pressing, with no evidence of deleterious effects from metallic contamination arising from contact with the compounding and molding equipment. By using ceramic injection molding to fabricate composite preforms, and then laying up the preforms to form larger composite arrays, an approach has been demonstrated for net-shape manufacturing of piezoelectric composite transducers in large quantities. Ac knowledaements This work was funded by the Office of Naval Research under the direction of Mr. Stephen E. Newfield. The authors wish to thank Ms. Hong Pham for technical assistance, and Dr. Thomas Shrout of the Materials Research Laboratory, Penn. State University for electrical measurements. References l R. E. Newnham et al, Composite Piezoelectric Transducers, Materials in Engineering, Vol. 2, pp. 93-106, Dec. 1980. 21 C. Nakaya et al, IEEE Ultrasonics Symposium Proc., Oct. 16-18, 1985, p 634. 131 S. D. Darrah et al, Large Area Piezoelectric Composites, Proc. of the ADPA Conference on Active Materials and Structures, Alexandria, Virginia, Nov. 4-8, 1991, Ed. G. Knowles, Institute of Physics Publishing, pp 139-142. A. Safari and D. J. Waller, Fine Scale PZT Fiber/Polymer Composites, presented at the ADPA Conference on Active Materials and Structures, Alexandria, Virginia, Nov. 4 1 4-8, 1991. 5 U. Bast, D. Cramer and A. Wolff, A New Technique for the Production of Piezoelectric Composites with 1-3 Connectivity, Proc. of the 7th CIMTEC, Montecatini, Italy, June 24-30, 1990, Ed. P. Vincenzini, Elsevier, pp 2005-201 5. G. Bandyopadhyay and K. W. French, Fabrication of Near-net Shape Silicon Nitride Parts for Engine Application, J. Eng. for Gas Turbines And Power, 108, J. Greim et al, Injection Molded Sintered Turbocharger Rotors, Proc. 3rd. Int. Symp. on Ceramic Materials and Components for Heat Engines, Las Vegas, Nev., pp. 1365- 1375, Amer. Cer. Soc. 1989. 61 pp 536-539, 1986. 171 163 制作压电陶瓷莱斯利J. Bowen和肯尼思W.法国,材料Systems公司53 Hillcrest路,康科德,硕士01742摘要在材料研究实验室,宾州州立大学研究已经证明改进水听器表现的潜力使用压电的制陶艺术/聚合物合成物. 为这些合成物,材料系统有成本效益的制造业技术正追求一制陶艺术的制造接近注射模塑. 本文简要概述主要特征的陶瓷注塑成型工艺, 接着介绍的方式和方法可以被用来制造压电陶瓷/聚合物复合材料. 性能和应用注塑压电陶瓷与常规加工材料.简介压电的制陶艺术/聚合物合成物给予关于单相陶瓷和聚合物阶段制陶艺术压电的材料在遥感和实际应用两方面设计多技能和表现优势。这些合成物已经在以及发展的海军应用高分辨医学超声中找出使用. 在过去13年对许多实验室进行了已建成组合配置和评价. 全球最成功的组合,指定1-3复合冈维尔的五线谱l 有一个连在尺寸上陶瓷相(压电纤维)控制在一个三维连通有机高分子阶段. 水听器人物优异这种复合材料可取得超过一万倍以上的固体压电陶瓷由适当选择的阶段性特征和复合结构在宾夕法尼亚州立复合材料l进行手工调挤压压电陶瓷棒在跳汰及封装环氧树脂,然后切片到适当的厚度和极化的陶瓷. 除了展现优越的技术性能,这种材料, 在宾夕法尼亚州工作的突出困难,编造1-3复合材料的大规模甚至为原型的目的. 这些措施包括:1）把许多的许多PZT纤维排成一排在包装期间经过聚合物和支撑要求.2） 2)在滑行期间电介质故障,起源于遭遇在一典型大阵列.中一根或更多有缺陷纤维的重要可能性的高发生.过去五年已做了一些尝试,以简化装配过程1-3传感器与有意提高制造业的可行性,并降低材料成本. 早期从事固体切丁块压电陶瓷成为理想的配置和回填土的空间内的一种高分子相. 这项技术已广泛接受了超声医学业生产高频传感器2. 最近, 纤维材料股份有限公司已证明适用其织造工艺纤维复合材料向大会压电陶瓷复合材料 3. 另勘探技术涉及复制的多孔面料有适当的连通4.为极其好刻度合成物,纤维,大约25到100 pn和超过五一个尺寸与另一个尺寸之比有直径需要来遭遇装置表现目标. 因此,这些困难被附加挑战用形成没有缺点和处理在大数量中极其好纤维构成了. 最近,研究人员在西门子公司已表明很细尺度复合材料可以产生一个逃犯模具技术. 但是,这种方法需要制作一个新的模具,每部分5.本文描述了一种新方法,压电复合材料的制备,即:陶瓷注射成型. 陶瓷注射成型技术是一种有成本效益的制备方法双方海军的压电陶瓷/聚合物复合材料的制备超细规模压电复合材料,例如那些需要高频医用超声和无损评价. 注塑成型过程中,克服困难,装配为主的陶瓷纤维复合成换用网状预成型品陶瓷纤维阵列. 除了这方面的优势, 这一进程使得有可能建造复合传感器具有更复杂的陶瓷元件几何比原先设想导致更大的灵活性,设计为改进的声阻抗匹配和横向模式取消加工工艺注塑广泛应用于塑料业作为一种手段,快速大量生产,形状复杂,在成本低. 应用陶瓷一直最成功的小型截面形状,例如: 螺纹指南,及大型复杂形状不需要烧结密度高,如涡轮叶片铸造刀片. 最近,这一进程已展开调查,作为生产工艺热发动机涡轮部件6,7图1:注射模塑过程路线.注塑成型用于PZT成型见图1. 注的热点热塑性混合陶瓷粉及有机结合成一个冷却结晶复杂的形状,可以形成与方便与快捷通常与塑料成型. 防范措施,如硬面临的金属接触面,这些都是重要的,以尽量减少金属污染的加剧和成型机器. 陶瓷的粘结剂必须拆除非破坏性地,使成为必要高固体量,严格控制粘结剂,拆除过程中, 和正确装夹. 一旦粘结剂是拆掉,随后射击极化和环氧包封过程类似于常规pzti聚合物复合1. 因此,过程具有以下优点替代加工路线:复杂近净形能力处理许多纤维同时发生; 快速吞吐量(通常每秒); 兼容性与统计过程控制; 低的材料浪费; 灵活应变传感器设计(允许变化压电元件间距和形状); 成本低,在中度到高度卷. 总的来说,由于高的初始成本,工装, 陶瓷注射成型是最好的应用复杂形状零件需要低成本高产量制造和评价采取这种办法,编造1-3压电复合载在图2a, 它说明了压电陶瓷预制棒的概念,光纤定位是实现以共同塑造积分陶瓷基地. 聚合物后封装在陶瓷拆除磨. 除了处理许多纤维这预制棒做法使广大纬度在选择压电陶瓷元件几何形状的综合性能优化. 工具的设计是成功的重要注塑压电陶瓷复合材料. 办法列于图2b用途形工具刀片允许改变部分设计,又不过分更换工具成本. 图2c显示了个体预制棒配置,能够形成较大的阵列图2:预制棒的方法综合加工.在实践中, 材料成型参数必须优化整合注塑模具设计实现完整的预制弹射后成型. 关键参数,包括:压电/粘合剂比,压电元件直径和锥形,基地PZT的厚度,刀具表面光洁度, 而塑造的一部分弹射机制设计. 为了评价这些工艺参数,又不过分工具成本工具设计,仅有两排19PZT的每一分子已经通过实验目的. 每一行包含有三个 (0,1和2度)和两个直径(0.5lmm). 容纳成型收缩, 大小坯维持在5ox50mm以尽量剪过的最外层纤维在冷却部分的成型周期.图3:注射塑造1-3混合成的预成型品.图3显示绿色陶瓷预制装配使用此工具配置. 看到所有的PZT分子赶出完好无损后成型,包括具有无纵一端渐渐变细变尖方便弹射. 慢热空气已被认为是一种合适的方法有机结合搬迁. 最后,烧出预制棒烧结在气氛97-98%的理论密度. 没有遇到任何问题与控制体重烧结过

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