T型轴盘零件液压自定心自动夹紧夹具设计[三维图]【8张CAD图纸和说明书】【GJ系列】
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编号无锡太湖学院毕业设计(论文)相关资料题目: 液压自定心自动夹紧夹具设计 信机 系 机械工程及自动化专业学 号: 0923090学生姓名: 杨建华 指导教师: 陈伟明 (职称:教授 ) (职称: ) 2013年5月25日目 录一、毕业设计(论文)开题报告二、毕业设计(论文)外文资料翻译及原文三、学生“毕业论文(论文)计划、进度、检查及落实表”四、实习鉴定表无锡太湖学院毕业设计(论文)开题报告题目: 液压自定心自动夹紧夹具设计 信机 系 机械工程及自动化 专业学 号: 0923090 学生姓名: 杨建华 指导教师: 陈伟明 (职称:教授 ) (职称: ) 2013年5月25日 课题来源本课题来源于一家致力于航空零件和汽车零件精密铸造和精密加工的企业。其加工的零件都是一些精度要求高、工艺复杂的零件。零件座体(材料为铝合金)就是典型的壳体零件。此零件批量大已成为公司的一个新的经济增长点。此前的工艺装备为普通三爪卡盘对A的同轴度0.1,基本上不能保证,检测结果在0.15左右,这样后道工序定位时,会影响其它孔的加工位置,造成零件废品率较高,必须改进。又由于该零件批量大,原有三爪定位时车加工转速只有500r/min,按照公司精益生产的要求,也需要改进来提高生产效率。故提出此课题!课题的目的及意义夹具从产生到现在,大约可以分为三个阶段:第一个阶段主要表现在夹具与人的结合上,这是夹具主要是作为人的单纯的辅助工具,是加工过程加速和趋于完善;第二阶段,夹具成为人与机床之间的桥梁,夹具的机能发生变化,它主要用于工件的定位和夹紧。人们越来越认识到,夹具与操作人员改进工作及机床性能的提高有着密切的关系,所以对夹具引起了重视;第三阶段表现为夹具与机床的结合,夹具作为机床的一部分,成为机械加工中不可缺少的工艺装备。为解决大批量产品的加工,20世纪50年代国外就开始研究高速机床、专用机床、高速刀具、专用刀具。随着以上课题不断的攻破,机械制造业获得了重大进展,但是工件的定位、夹紧所必须的夹具仍是不可缺少的工艺装备。机床、刀具的快速、耐用对夹具也提出了更高更新的要求。因此需要一种结构简单、自动化程度高、夹紧点固定、夹紧力可靠、装夹释放工件快速、能减少工人的劳动强度和人为因素的不稳定性的夹具。为了满足高速、专用机床的加工要求,研制液压夹具,它选用标准液压元件,根据加工零件特性设计机械部件并把其有机的装配、连接在一起设计的。它具有以下特点:一是针对某个零件设计的专用工装;二是液压元件为标准化、系列化的模块,可以实现工件装夹的自动化;三是液压夹具的使用可以提高生产效率及产品质量,解决技术关键,提高企业的工艺装备系数。定位精度的关键在于夹具力在定位和夹具过程中,保持恒定不变,从而确保了同一道工序下的加工质量一致性,即提高重复精度,故此由于变形造成的废品率将会微乎其微。成批零部件的互换性也会达到理想的指标,然而这一点几乎是机械夹具无法做到的。在针对无法设定刚性支撑或加工薄壁零件时,液压辅助支撑是最佳的选择。在一个固定夹具体上,采用机械定位,夹紧加工后再将它们卸下,这通常是要花很多时间的一个步骤,为了实现高产高效,工件的定位、支撑夹紧和夹具的快速松开,以及操作方便安全都是非常重要的环节。使对于加工一个较大的工件,选用半自动化或全自动化夹具是非常具有经济价值的。液压定位和夹紧是一项非常有效和可靠的加工技术。用液压夹具的第一个优势是能节省夹紧和松卸工件时所花费的大量的时间。传统的机械夹具在松开和夹紧工作是都要费力的用扳手旋拧螺母和移动压板。然而,液压夹具只需要通过控制油路的通断,就可实现夹具的完整的顺序动作控制且定位精度会很高。课题任务本次课题的任务:是设计液压自定心自动夹紧夹具,了解液压夹具的工作原理结构特点;学习机构设计方法,学习和巩固所学的专业文化知识,培养结构设计能力; 绘制设备总图、主要零件图,编写设计说明书。液压夹具工作原理和构成液压夹具就是用液压元件代替机械零件实现对工件的自动定位、支承夹紧的夹具,液压元件具有很高的精度、稳定性及使用寿命。通过把选用的液压元件和设计的机械部分装配在一起,就可得到所需的夹具。液压夹具能保证工件在规定位置上准确定位和牢固的夹紧,并能通过浮动支撑减少加工中的振动和变形,还能利用自动控制压板的压紧和抬起在加工中让开夹紧位置。保证在精密加工时的准确定位,还能完成手动夹具无法完成的支撑、夹紧和快速释放。大批量产品使用液压夹具能产生明显的经济效益。液压夹具由油箱、柱塞泵、工作油缸和夹具体组成。液压夹具的设计与制造(1)依据被加工零件的几何形状、加工内容及应用场合(指夹具用于单机或自动线),如何满足生产节拍要求等进行夹具的工艺设计。确定夹具的轮廓尺寸, 并依据整个系统的要求,考虑设备和人身的安全。(2)拟定在一个工作循环内夹具各部分的动作顺序,从而选定顺序阀和其它液压控制部件。(3)计算加工过程所产生的切削力及力的方向,并考虑一定的安全系数。从而便于液压控制系统元件的选用,这些要与所选用的机床或加工中心的能力相一致。(4)根据切削力,按有关公式计算出所需的夹紧力。(5) 确定零件的安装位置和支承、定位结构,并尽可能地提高敞开性,以利于加工、排屑和散热。(6) 依据零件的大小、形状、材料和加工要求,确定定位、夹紧装置的形状及数量。(7) 确定需要的总油量,以选择相应的液压油泵。(8)设计液压管路。夹具的装配是以底板为基准进行的。箱体、工作面板上的加工部位,一般都在加工中心上加工,并经三座标测量机检测,以保各基础元件位置准确。工作面板上装好各基础元件后,也要经三座标测量机检测。装配时, 先将各工作面板固定在箱体上,再把箱体安装在底板上,最后进行液压系统的调试。拟完成课题的方法1明确设计要求,认真调查研究,收集设计材料,确定夹具的结构方案;2设计中需要充分分析定位误差影响因素、设计中着重考虑误差计算和定位方案比较;3通过老师的指导借阅读取大量的有关夹具设计的课外书籍,通过前人的经验总结再集合自己的想法,毕业设计一定能完成的;4就于时间紧迫,所以我会尽最大努力,运用所学的知识有步骤有计划的完成自己的毕业设计。研究内容 制定零件的夹紧方案。 装夹卸料过程。 液压系统工作原理。研究计划及预期成果研究计划:2012年11月15日-2012年12月25日:查阅论文相关参考资料,填写开题报告书。2013年1月11日-2013年3月5日:填写毕业实习报告。2013年3月8日-2013年3月14日:按照要求修改毕业设计开题报告。2013年3月15日-2013年3月21日:学习并翻译一篇与毕业设计相关的英文材料。2013年3月22日-2013年4月11日:方案设计研究。2013年4月12日-2013年4月25日:结构工程图纸设计。2013年4月26日-2013年5月20日:完成毕业设计论文。预期成果:实现:1.装夹过程:首先零件装夹在涨紧套外,机床油缸向后运动带动拉杆和锥套,由于锥度定心,向后运动后,锥套与涨紧套的作用直径慢慢变大,涨紧套开始与零件接触定位,实现自定心加紧。2.卸料过程:加工完成后,机床油缸向前运动,推动拉杆并带动锥套,涨紧套向内收缩,夹紧力慢慢松开后,取下零件,工序加工完成。已具备的条件和尚需解决的问题 熟练掌握AutoCAD,UG等绘图软件,单独查阅相关机械文件,相关专业知识。 缺少实践经历可能导致设计的结构出现与实际情况不合理的地方。指导教师意见指导教师签名: 年 月 日 教研室(学科组、研究所)意见教研室主任签名: 年 月 日 系意见 主管领导签名: 年 月 日英文原文Mechanical DesignAbstract:A machine is a combination of mechanisms and other components which transforms, transmits. Examples are engines, turbines, vehicles, hoists, printing presses, washing machines, and movie cameras. Many of the principles and methods of design that apply to machines also apply to manufactured articles that are not true machines. The term mechanical design is used in a broader sense than machine design to include their design. the motion and structural aspects and the provisions for retention and enclosure are considerations in mechanical design. Applications occur in the field of mechanical engineering, and in other engineering fields as well, all of which require mechanical devices, such as switches, cams, valves, vessels, and mixers.Keywords: Mechanical Design mechanisms Design ProcessThe Design ProcessDesigning starts with a need real.Existing apparatus may need improvements in durability, efficiency, weight, speed, or cost. New apparatus may be needed to perform a function previouslydone by men, such as computation, assembly, or servicing. With the objective wholly or partlyIn the design preliminary stage, should allow to design the personnel fully to display the creativity, not each kind of restraint. Even if has had many impractical ideas, also can in the design early time, namely in front of the plan blueprint is corrected. Only then, only then does not send to stops up the innovation the mentality. Usually, must propose several sets of design proposals, then perform the comparison. Has the possibility very much in the plan which finally designated, has used certain not in plan some ideas which accepts.When the general shape and a few dimensions of the several components become apparent, analysis can begin in earnest. The analysis will have as its objective satisfactory or superior performance, plus safety and durability with minimum weight, and a competitive cost. Optimum proportions and dimensions will be sought for each critically loaded section, together with a balance between the strengths of the several components. Materials and their treatment will be chosen. These important objectives can be attained only by analysis based upon the principles of mechanics, such as those of static for reaction forces and for the optimum utilization of friction; of dynamics for inertia, acceleration, and energy; of elasticity and strength of materials for stress and deflection; of physical behavior of materials; and of fluid mechanics for lubrication and hydrodynamic drives. The analyses may be made by the same engineer who conceived the arrangement of mechanisms, or, in a large company, they may be made by a separate analysis division or research group. Design is a reiterative and cooperative process, whether done formally or informally, and the analyst can contribute to phases other than his own. Product design requires much research and development. Many Concepts of an idea must be studied, tried, and then either used or discarded. Although the content of each engineering problem is unique, the designers follow the similar process to solve the problems. Product liability suits designers and forced in material selection, using the best program. In the process of material, the most common problems for five (a) dont understand or not use about the latest application materials to the best information, (b) failed to foresee and consider the reasonable use material may (such as possible, designers should further forecast and consider due to improper use products. In recent years, many products liability in litigation, the use of products and hurt the plaintiff accused manufacturer, and won the decision), (c) of the materials used all or some of the data, data, especially when the uncertainty long-term performance data is so, (d) quality control method is not suitable and unproven, (e) by some completely incompetent persons choose materials.Through to the above five questions analysis, may obtain these questions is does not have the sufficient reason existence the conclusion. May for avoid these questions to these questions research analyses the appearance indicating the direction. Although uses the best choice of material method not to be able to avoid having the product responsibility lawsuit, designs the personnel and the industry carries on the choice of material according to the suitable procedure, may greatly reduce the lawsuit the quantity. May see from the above discussion, the choice material people should to the material nature, the characteristic and the processing method have comprehensive and the basic understanding. Finally, a design based upon function, and a prototype may be built. If its tests are satisfactory, the initial design will undergo certain modifications that enable it to be manufactured in quantity at a lower cost. During subsequent years of manufacture and service, the design is likely to undergo changes as new ideas are conceived or as further analyses based upon tests and experience indicate alterations. Sales appeal.Some Rules for DesignIn this section it is suggested that, applied with a creative attitude, analyses can lead to important improvements and to the conception and perfection of alternate, perhaps more functional, economical,and durable products. To stimulate creative thought, the following rules are suggested for the designer and analyst. The first six rules are particularly applicable for the analyst.1. A creative use of need of physical properties and control process.2. Recognize functional loads and their significance.3. Anticipate unintentional loads.4. Devise more favorable loading conditions.5. Provide for favorable stress distribution and stiffness with minimum weight.6. Use basic equations to proportion and optimize dimensions.7. Choose materials for a combination of properties.8. Select carefully, stock and integral components.9. Modify a functional design to fit the manufacturing process and reduce cost.10. Provide for accurate location and noninterference of parts in assembly. Machinery design covers the following contents.1. Provides an introduction to the design process , problem formulation ,safety factors.2. Reviews the material properties and static and dynamic loading analysis ,Including beam , vibration and impact loading. 3. Reviews the fundamentals of stress and defection analysis. 4. Introduces fatigue-failure theory with the emphasis on stress-life approaches to high-cycle fatigue design, which is commonly used in the design of rotation machinery. 5. Discusses thoroughly the phenomena of wear mechanisms, surface contact stresses ,and surface fatigue. 6. Investigates shaft design using the fatigue-analysis techniques. 7. Discusses fluid-film and rolling-element bearing theory and application 8. Gives a thorough introduction to the kinematics, design and stress analysis of spur gears , and a simple introduction to helical ,bevel ,and worm gearing. 9. Discusses spring design including compression ,extension and torsion springs. 10. Deals with screws and fasteners including power screw and preload fasteners. 11. Introduces the design and specification of disk and drum clutches and brakes.Machine DesignThe complete design of a machine is a complex process. The machine design is a creative work. Project engineer not only must have the creativity in the work, but also must in aspect and so on mechanical drawing, kinematics, engineerig material, materials mechanics and machine manufacture technology has the deep elementary knowledge. One of the first steps in the design of any product is to select the material from which each part is to be made. Numerous materials are available to todays designers. The function of the product, its appearance, the cost of the material, and the cost of fabrication are important in making a selection. A careful evaluation of the properties of a. material must be made prior to any calculations. Careful calculations are necessary to ensure the validity of a design. In case of any part failures, it is desirable to know what was done in originally designing the defective components. The checking of calculations (and drawing dimensions) is of utmost importance. The misplacement of one decimal point can ruin an otherwise acceptable project. All aspects of design work should be checked and rechecked. The computer is a tool helpful to mechanical designers to lighten tedious calculations, and provide extended analysis of available data. Interactive systems, based on computer capabilities, have made possible the concepts of computer aided design (CAD) and computer-aided manufacturing (CAM). How does the psychologist frequently discuss causes the machine which the people adapts them to operate. Designs personnels basic responsibility is diligently causes the machine to adapt the people. This certainly is not an easy work, because certainly does not have to all people to say in fact all is the most superior operating area and the operating process. Another important question, project engineer must be able to carry on the exchange and the consultation with other concerned personnel. In the initial stage, designs the personnel to have to carry on the exchange and the consultation on the preliminary design with the administrative personnel, and is approved. This generally is through the oral discussion, the schematic diagram and the writing material carries on. If front sues, the machine design goal is the production can meet the human need the product. The invention, the discovery and technical knowledge itself certainly not necessarily can bring the advantage to the humanity, only has when they are applied can produce on the product the benefit. Thus, should realize to carries on before the design in a specific product, must first determine whether the people do need this kind of productMust regard as the machine design is the machine design personnel carries on using creative ability the product design, the system analysis and a formulation product manufacture technology good opportunity. Grasps the project elementary knowledge to have to memorize some data and the formula is more important than. The merely service data and the formula is insufficient to the completely decision which makes in a good design needs. On the other hand, should be earnest precisely carries on all operations. For example, even if places wrong a decimal point position, also can cause the correct design to turn wrongly.A good design personnel should dare to propose the new idea, moreover is willing to undertake the certain risk, when the new method is not suitable, use original method. Therefore, designs the personnel to have to have to have the patience, because spends the time and the endeavor certainly cannot guarantee brings successfully. A brand-new design, the request screen abandons obsoletely many, knows very well the method for the people. Because many person of conservativeness, does this certainly is not an easy matter. A mechanical designer should unceasingly explore the improvement existing product the method, should earnestly choose originally, the process confirmation principle of design in this process, with has not unified it after the confirmation new idea.中文译文机械设计摘要: 机器一般是由机械装置和其它组件组成的。机器是一种用来转换或传递能量的装置,比如:发动机、涡轮机、车辆、起重机、印刷机、洗衣机、照相机和摄影机等。好多原则和设计方法不仅适用于机器设计,也适用于非机器的设计。术语中的“机械装置设计” 的含义要比“机械设计”的含义更加的广泛,机械设计包括在机械装置中。在分析运动及设计结构时,要把产品外型以及以后的保养也要考虑在机械设计当中。在机械工程领域中,以及其它工程领域中,所有这些都需要机械设备,比如:开关、凸轮、阀门、船舶以及搅拌机等。关键词: 设计流程 设计规则 机械设计设计流程设计开始之前就要想到机器的实际性,现存的机器需要在耐用性、效率、重量、速度,或者成本上得到改善。新的机器必需具有以前机器所能执行的功能。在设计的初始阶段,应该允许设计人员充分发挥创造性,不要受到任何约束。即使产生了许多不切实际的想法,也会在设计的早期,即在绘制图纸之前被改正掉。只有这样,才不致于阻断创新的思路。通常,还要提出几套设计方案,然后加以比较。很有可能在这个计划最后决定中,使用了某些不在计划之内的一些设想。一般的当外型特点和组件部分的尺寸特点分析得透彻时,就可以全面的设计和分析。接着还要客观的分析机器性能的优越性,以及它的安全、重量、耐用性,并且竞争力的成本也要考虑在分析结果之内。每一个至关重要的部分要优化它的比例和尺寸,同时也要保持与其它组成部分相协调。也要选择原材料和处理原材料的方法。通过力学原理来分析和实现这些重要的特性,如那些静态反应的能量和摩擦力的最佳利用,像动力惯性、加速动力和能量;包括弹性材料的强度、应力和刚度等材料的物理特性,以及流体润滑和驱动器的流体力学。设计的过程是重复和合作的过程,无论是正式或非正式的进行,对设计者来说每个阶段都很重要。最后,以图样为设计的标准,并建立将来的模型。如果它的测试是符合事先要求的,则再将对初步设计进行某些修改,使它能够在制造成本上有所降低。产品的设计需要不断探索和发展。许多方案必须被研究、试验、完善,然后决定使用还是放弃。虽然每个工程学问题的内容是独特的,但是设计师可以按照类似的步骤来解决问题。产品的责任诉讼迫使设计人员和公司在选择材料时,采用最好的程序。在材料过程中,五个最常见的问题为:(a)不了解或者不会使用关于材料应用方面的最新最好的信息资料;(b)未能预见和考虑材料的合理用途(如有可能,设计人员还应进一步预测和考虑由于产品使用方法不当造成的后果。在近年来的许多产品责任诉讼案件中,由于错误地使用产品而受到伤害的原告控告生产厂家,并且赢得判决);(c)所使用的材料的数据不全或是有些数据不确定,尤其是当其性能数据长期不更新;(d)质量控制方法不适当和未经验证;(e)由一些完全不称职的人员选择材料。通过对上述五个问题的分析,可以得出这些问题是没有充分理由而存在的结论。对这些问题的研究分析可以为避免这些问题的出现而指明方向。尽管采用最好的材料选择方法也不能避免发生产品责任诉讼,设计人员和工业界按照适当的程序进行材料选择,可以大大减少诉讼的数量。从以上的讨论可以看出,选择材料的人们应该对材料的性质,特点和加工方法有一个全面而基本的了解。在随后生产和售后服务的几年中,要接受新观念的变化,或者由试验和经验为基础,进一步分析并改进。一些设计规则在本节中,建议要运用创造性的态度来替代和改进。也许会创造出更实用、更经济、更耐用的产品。为了激发创造性思维,下列是设计和分析的建议规则。前六个规则对设计者来说特别适用。1. 要有创造性的利用所需要的物理性质和控制过程。2. 认识负载产生的影响及其意义。3. 预测没有想到的负载。4. 要创造出对载荷更为有利的条件。5. 提供良好的应力分布和最小的刚度条件。6. 运用最简单的方程来优化体积和面积。7. 选择组合材料。8. 仔细选择所备的原料和不可缺少的组件。9. 调整有效的设计方案,以适应生产过程和降低成本。10. 规定好准确的位置条件为了使组件安装时不干涉。机械设计包括以下内容:1. 对设计过程、设计所需要公式以及安全系数进行介绍。2. 回顾材料特性、静态和动态载荷分析,包括梁、振动和冲击载荷。3. 回顾应力的基本规律和失效分析。4. 介绍静态失效理论和静态载荷下机械断裂分析。5. 介绍疲劳失效理论并强调在压力条件下接近高循环的疲劳设计,这通常用在旋转机械的设计中。6. 深入探讨机械磨损机理、表面接触应力和表面疲劳现象。7. 使用疲劳分析技术校核轴的设计。8. 讨论润滑油膜与滚动轴承的理论和应用。9. 深入介绍直齿圆柱齿轮的动力学、设计和应力分析,并简单介绍斜齿轮、锥齿轮和涡轮有关方面的问题。10. 讨论弹簧设计、螺杆等紧固件的设计,包括传动螺杆和预紧固件。11. 介绍盘式和鼓式离合器以及制动器的设计和技术说明。机械设计一台完整机器的设计是一个复杂的过程。机械设计是一项创造性的工作。设计工程师不仅在工作上要有创造性,还必须在机械制图、运动学、工程材料、材料力学和机械制造工艺学等方面具有深厚的基础知识。任何产品在设计时第一步就是选择产品每个部分的构成材料。许多的材料被今天的设计师所使用。对产品的功能,它的外观、材料的成本、制造的成本作出必要的选择是十分重要的。对材料的特性必须事先作出仔细的评估。仔细精确的计算是必要的,以确保设计的有效性。在任何失败的情况下,最好知道在最初设计中有有缺陷的部件。计算(图纸尺寸)检查是非常重要的。一个小数点的位置放错,就可以导致一个本可以完成的项目失败。设计工作的各个方面都应该检查和复查。计算机是一种工具,它能够帮助机械设计师减轻繁琐的计算,并对现有数据提供进一步的分析。互动系统基于计算机的能力,已经使计算机辅助设计(CAD)和计算机辅助制造(CAM)成为了可能。心理学家经常谈论如何使人们适应他们所操作的机器。设计人员的基本职责是努力使机器来适应人们。这并不是一项容易的工作,因为实际上并不存在着一个对所有人来说都是最优的操作范围和操作过程。另一个重要问题,设计工程师必须能够同其他有关人员进行交流和磋商。在开始阶段,设计人员必须就初步设计同管理人员进行交流和磋商,并得到批准。这一般是通过口头讨论,草图和文字材料进行的。如前所诉,机械设计的目的是生产能够满足人类需求的产品。发明、发现和科技知识本身并不一定能给人类带来好处,只有当它们被应用在产品上才能产生效益。因而,应该认识到在一个特定的产品进行设计之前,必须先确定人们是否需要这种产品。应当把机械设计看成是机械设计人员运用创造性的才能进行产品设计、系统分析和制定产品的制造工艺学的一个好机会。掌握工程基础知识要比熟记一些数据和公式重要的多。只使用数据和公式是不足以在一个好的设计中做出所需的全部决定的。另一方面,应该认真精确的进行所有的运算。例如,即使将一个小数点的位置放错,也会使正确的设计变成错误的。一个好的机械设计人员应该勇于提出新的想法,而且愿意承担一定的风险,当新的方法不适用时,就使用原来的方法。因此,设计人员必须要有耐心,因为 所花费的时间和努力并不能保证带来成功。一个全新的设计,要求屏弃许多陈旧的,为人们所熟知的方法。由于许多人墨守成规,这样做并不是一件容易的事。一位机械设计师应该不断地探索改进现有的产品的方法,在此过程中应该认真选择原有的、经过验证的设计原理,将其与未经过验证的新观念结合起来。新设计本身会有许多的缺陷和未能预料的问题发生,只有当这些缺陷和问题被解决之后,才能体现出新产品的优越性。因此,一个性能优越的产品诞生的同时,也伴随着较高的风险。应该强调的是,如果设计本身不要求采用全新的方法,就没有必要仅仅为了变革的目的而采用新方法。
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