机械毕业设计英文外文翻译65超高液压下O形环角密封的实验研
附录
附录A 外文文献原文
Ultra-high hydraulic angle O-ring seal
the experimental study
Abstract :
Nitrile rubber O-ring EHV end Kok containers sealed imposed on containers so high hydraulic seal experimental series. The results show that angle enclosed structure, as well as O-ring compression rate, diameter, enclosed space, rubber hardness, The sealing surface roughness and seal the form and position tolerances, and other relevant factors reasonable match, strict control, the use of ordinary O-ring can be achieved 138MPa ultrahigh static hydraulic seal.
Keywords : EHV static O-ring seal
Along with the rapid modern industrial development, UHP increasingly widespread use of the ultrahigh-pressure killing Hill, super-high-speed refrigeration, Expanded food industry, supercritical fluid extraction, low-salt treatment, Expanded room temperature and high pressure compression fermentation and other typical applications. Such equipment is produced by the many advantages of increasing people's attention. If UHP food production is instantaneous pressure, role uniform, safe operation and low energy consumption to maintain good natural food color, smell and taste and nutritional characteristics of the components, with 21 new food simple, safe, natural, nutrition, health, and environmental protection in consumption demand. Which have significant social and economic benefits, has tremendous market potential and broad prospects for development.
However, China's current UHP food production industries badly need to improve the level of equipment, can produce economic, Energy-saving, safe and efficient handling
equipment constrains EHV food processing technology marketing major bottleneck. Among them, how to create economic EHV containers and ensure that the high pressure seal containers is particularly difficult lie. UHV equipment can operate normally sealed to a large extent depends on the integrity of the structure. High pressure sealing device about the weight of the containers, weighing 10% to 30%. and the cost accounts for 15% ~ 40%
of the total cost, design sealed pressure vessel design is an important component. Because many UHV equipment for space operations, the operation requires not only material can be quickly loaded fast again. and the frequent requirement in the open despite repeated achieve reliable sealing, General use of fast open-closed structure since the close of this problem can be resolved. Ordinary rubber O-ring seal structure is simple, convenience, low cost, compact installation, easy to use and has since closed closely role advantages, the industry is widely used. So experiment nitrile rubber (NBR) O-rings (32.5 × specifications
for the 3.55G. implementation of the standards for GB3452.1-92) Kok sealed experiments.
1 O-ring seal from the Principle
1) state preload
O-ring sealed site after its general section by a certain amount of compression, as O-rings have good flexibility, the interface will have a certain degree of contact pressure, thus achieving preload under seal.
2) state
When the sealed chamber filled with hydraulic media, the role of media pressure, the O-ring to shift the low-pressure side, and the seal gap closed to live. With the increase of media pressure, the contact pressure has also been increasing, the peak is always greater than the fluid pressure. This will guarantee that the O-ring seal the sealing function, reflects the O-ring seal the ability to automatically sealed. Experience has shown that for ordinary rubber materials, generally 13 × 105Pa than the standard pressure.
2 the main parameters of Seal
O-ring seal effects and compression rate, diameter, enclosed space, rubber hardness, The sealing surface roughness and seal the form and position tolerances, and other factors are closely related. The impact of O-ring seal properties of various factors, as
long as the parameters of a design will reduce the unreasonable results sealed, even result in seal failure. Now, therefore discuss the impact of specific factors to determine the value .
1）compression rate
After the O-shape link loads the seal spot, its section generally receives a quota the compression, because the O shape link has the good elasticity, docking touches personally meets has the certain contact pressure, thus realizes under the pre- tight condition seal. 2) active status
After the sealed chamber sufficiently enters the hydraulic pressure medium, in under the medium pressure function, the O shape link carries over a low pressure side, seals up the seal gap. Along with the medium pressure increase, the contact pressure also along with it increase, its peak value always is bigger than the fluid medium pressure. This has guaranteed the O shape packing ring seal function, also has reflected the O shape packing ring automatic sealing ability. The experience indicated that, regarding the ordinary rubber material, generally as the standard compares the pressure take 13×105 P a.
3) seal gap
O-ring gap in the high-pressure easily deformed easily be squeezed into the sealed space in order to cause damage, it is necessary to the O-ring seal gap to be strictly controlled. To prevent O-ring extrusion occurred, and to take into account the difficulty of installing and dismantling, The experimental space for the sealing of 0.1mm.
3 experimental devices and airtight structure
1) hardness
Elastic modulus small O-ring, the maximum contact stress small, extrusion capacity, easy to destroy. So when a high pressure, high hardness should use the O-ring. In this experiment the O-ring hardness IRHD (International Rubber Hardness levels), 80 ± 5.5) sealing surface roughness Seal the surface roughness is sealing technique to measure an important indicator. If the sealing surface Department has manufacturing defects or vertical scratch, it is very easy to seal leakage media. "Ultrahigh Pressure Vessel Safety Technology Supervision" provided EHV containers sealing surface roughness Ra should be
less than or equal to 0 . 8 μ m. The experimental sealing surface roughness Ra from 0.4 μ m.
2) seals the form and position tolerances secret
Sealed cylindrical surface of roundness, cylindricity tolerance by eight precision selection Hole-face vertical axis of tolerance by seven precision selection.
4 experiment
(1) O-ring uniform surface coating small grease. Cover and Arbors will use double-headed stud connection, and O-ring installed mandrels, Bolt pallets used to connect to the mandrels to compress O-ring;
(2) high-pressure pipe assembly, and the small joints nut nuts, Nut will joints and hydraulic media entrance of the threaded connection;
(3) under the pallets, containers and with the end caps on the map by a plate placed. Press access to power, two plate compactor next two pad; (4) access to power, preheat 5 minutes, Pressure relief valve rotation. 10 MPa to the differential pressure, pressure
per-Level 5 minutes to observe any leakage;
(5) Records Expander pressure on the indicator values and the hydraulic fluid leakage.
several experiments show that, as long as a reasonable choice and strictly control the impact of the sealing performance of the main factors figure, Individual use of ordinary O-ring seal structure cone 138MPa can achieve a reliable seal; As laboratory equipment constraints, the experiment is just 138MPa hydraulic seal, O-ring seals that there is a potential to be tapped.
O-ring seal structure of cone-shaped O-ring seal and the corresponding surface of the manufacture of certain deviation compensation, This reduces the manufacturing of precision requirements, this seal structure should be promoted; O-rings in the completed several high pressure seal, found his appearance minor extrusion gap phenomenon. This shows that the O-ring is achievable 138MPa about EHV sealed But media pressure is required to consider increased use of O-rings with the triangular pad combination sealed structure or use other sealing pathways to solve, but this paper to explore the impact of sealing performance of the main parameters of methods, there is still a definite reference
value. hubcap need to prevent extrusion of the limited space, it is worth further experiments.
附录B 外文文献中文翻译
超高液压下Ｏ形环角密封的实验研究
摘要:
采用丁腈橡胶O形环实现超高压容器端部角密封,对容器施加超高液压做系列密封实验。结果表明,采用角密封结构,并对O形环压缩率、截面直径、密封间隙、橡胶硬度、密封面的粗糙度和密封件的形
位公差等相关因素进行合理匹配,严格控制,使用普通O形环可以实现138MPa超高液压的静密封。
关键词: 超高压O形环静密封
随着现代工业的快速发展,超高压越来越广泛地运用到超高压杀茵、超高速冷冻、食品膨化工业、超临界流体萃取、低盐化处理、室温高压膨化以及加压发酵等典型应用场合。这类设备所生产的产品具有众多优越性,日益引起人们的普遍关注。如超高压食品的生产具有瞬间加压、作用均匀、操作安全和耗能低能很好地保持食物天然的色、香、味和营养成分的特点,符合21世纪新型食品简便、安全、天然、营养、卫生、环保的消费需求。因而有着显著的社会效益和经济效益,具有巨大的潜在市场和广阔的发展前景。
但是,现今我国的超高压食品的生产存在亟待提高工业装备水平的问题,能否制造出经济、节能、安全、高效的处理设备成为制约超高压食品处理技术市场推广的主要瓶颈。其中,如何经济地制造超高压容器并保证容器的超高压密封尤为难点之所在。超高压设备能否正常运行在很大程度上取决于密封结构的完善性。高压密封装置的重量约占容器总重的10%～30%,而成本却占总成本的15%～40%,因此密封设计工作是高压容器设计的重要组成部分。由于许多超高压设备为间隙操作,操作时不但要求物料能快装快卸,且要求在开启频繁的情况下仍能实现多次可靠密封,一般使用快开式自紧密封结构才能解决这一难题。普通O形橡胶密封环具有结构简单、制造方便、价格便宜、安装紧凑、使用方便和具有自紧密封作用等优点,被各行业广泛使用。因此实验采用丁
腈橡胶(NBR)O形环(规格为32.5×3.55G,执行标准为GB3452.1—92)进行角密封实验研究。
O形环的自紧密封原理
1)预紧状态
O形环装入密封部位后,其截面一般受到一定量的压缩,由于O形环有良好的弹性,对接触面会产生一定的接触压力,从而实现预紧状态下的密封。
2)工作状态
当密封腔充入液压介质后,在介质压力的作用下,O形环移向低压一侧,封闭住密封间隙。随着介质压力的增加,接触压力亦随之增加,其峰值总是大于流体介质压力。这就保证了O形密封环的密封功能,也反映了O形密封环的自动密封能力。经验表明,对于普通橡胶材料,一般以13×105Pa为标准比压。
2主要密封参数的确定
O形环的密封效果与压缩率、截面直径、密封间隙、橡胶硬度、密封面的粗糙度和密封件的形位公差等因素密切相关。在影响O形环密封性能的诸因素中,只要有1个参数的设计不合理就会降低其密封效果,甚至导致密封失效。因此下面就讨论一下各影响因素具体数值的确定。
1)压缩率
形环密封是典型的压缩型密封。O形环截面直径的压缩率是影响密封效果和使用寿命的重要参数。大多数情况下的泄漏与压缩量不足有关,但是过量压缩又会造成装拆困难和产生过大的残余变形,而这将严重缩短其使用寿命。因此应合理确定Ｏ形环的压缩率。压缩率Ｗ用下式表示:W=d0/hd0100%式中d0为O形环的截面直径(mm),h为O形环压缩后的截面尺寸。对于静密封压缩率Ｗ一般取10%～22%,本实验取为15%。
2)截面直径
对于相同的压缩量,截面直径大的O形环的接触宽度大,相应的最大接触应力小,因此在橡胶O形环满足结构工艺等其他要求的情况下,尽可能选择大截面的橡胶O形环。本实验容器密封面内孔直径为39mm,O形环截面直径取3.55mm。
3)密封间隙
O形环在高压力下很容易变形,容易被挤入密封间隙中去,造成损坏,因此必须对O 形环的密封间隙加以严格控制。为了防止O形环发生挤出现象,并考虑到装拆的难易程度,本实验的密封间隙取为0.1mm。
4)硬度
弹性模量小的O形环,则最大接触压应力小,挤出量大,易破坏。所以当内压很高时,应选用硬度较高的O形环。本实验采用的O形环硬度为1RHD(国际橡胶硬度等级80±5.5)
密封面的粗糙度密封面的粗糙度是密封技术中的一个重要衡量指标。如果密封面处有制造缺陷或纵向划痕,则密封介质很容易泄漏。《超高压容器安全技术监察规程》中规定超高压容器密封面的粗糙度Ra应当小于或等于0.8μm。本实验密封面的粗糙Ra取0.4μm。
5)密封件的形位公差密
封圆柱面的圆度、圆柱度公差按8级精度选取,端面对内孔轴线的垂直度公差按7级精度选取。
3实验装置与密封结构
(1)实验装置
实验装置由压力源(YZGB型液袋式液压胀管机)、高压连接管路、设计压力为200MPa 的超高压实验容器和轴向力平衡装置(250KN的压力机)组成。
(2)密封原理
当旋紧螺栓时,将带动托板向上移动压紧O形环,O形环将贴紧芯轴的锥面和容器器壁,与锥面和轴之间分别形成环密封带,形成预紧密封。在操作状态,随着介质(本实验加压介质为水)压力的增加,O形环的压缩量也随之增大,接触压力亦相应增加,从而实现可靠密封。
4实验过程
(1)将O形环表面均匀涂覆少量润滑脂。将端盖和芯轴用双头螺柱连接,把O形环安装到芯轴上,用螺栓将托板连接到芯轴上以压紧O形环;
(2)装配高压管、接头螺母和小螺母,将接头螺母与液压介质入口的螺纹连接;
(3)将下垫板、容器、端盖与上垫板按图1位置放置。接通压力机电源,使两平板压紧上下两垫板;
(4)接通电源,预热5min,旋转溢流阀加压。以10MPa的级差加压,每级保压5min,观察有无泄漏;
(5)记录胀管机上的压力显示仪的液压数值和液体泄漏情况。
经多次实验表明,只要合理选择并严格控制影响密封性能的各主要因素的数值,单独使用普通O形环锥面密封结构可以实现138MPa的可靠密封。由于实验设备的限制,本实验只做到138MPa的液压密封,O形环仍有一定的密封潜力可以挖掘。
突破了传统资料认为的O形环静密封最高压力为70MPa和当工作压力高于32MPa 需要加挡圈以防止间隙挤出的限定,值得进一步进行实验研究。O形环在完成多次超高压密封后,发现其外观有轻微间隙挤出现象。这表明O形环虽可实现138MPa左右的超高压密封,但若介质压力继续升高则需考虑使用O形环与三角垫的组合密封结构或利用
其他密封途径加以解决,但本文所探讨的影响密封性能的主要参数的确定方法仍有一定的参考意义。
毕业设计外文翻译资料
外文出处： 《Exploiting Software How to Break Code》By Greg Hoglund, Gary McGraw Publisher : Addison Wesley Pub Date : February 17, 2004 ISBN : 0-201-78695-8 译文标题： JDBC接口技术 译文： JDBC是一种可用于执行SQL语句的JavaAPI（ApplicationProgrammingInterface应用程序设计接口）。它由一些Java语言编写的类和界面组成。JDBC为数据库应用开发人员、数据库前台工具开发人员提供了一种标准的应用程序设计接口，使开发人员可以用纯Java语言编写完整的数据库应用程序。 一、ODBC到JDBC的发展历程 说到JDBC，很容易让人联想到另一个十分熟悉的字眼“ODBC”。它们之间有没有联系呢？如果有，那么它们之间又是怎样的关系呢？ ODBC是OpenDatabaseConnectivity的英文简写。它是一种用来在相关或不相关的数据库管理系统（DBMS）中存取数据的，用C语言实现的，标准应用程序数据接口。通过ODBCAPI，应用程序可以存取保存在多种不同数据库管理系统（DBMS）中的数据，而不论每个DBMS使用了何种数据存储格式和编程接口。 1．ODBC的结构模型 ODBC的结构包括四个主要部分：应用程序接口、驱动器管理器、数据库驱动器和数据源。应用程序接口：屏蔽不同的ODBC数据库驱动器之间函数调用的差别，为用户提供统一的SQL编程接口。 驱动器管理器：为应用程序装载数据库驱动器。 数据库驱动器：实现ODBC的函数调用，提供对特定数据源的SQL请求。如果需要，数据库驱动器将修改应用程序的请求，使得请求符合相关的DBMS所支持的文法。 数据源：由用户想要存取的数据以及与它相关的操作系统、DBMS和用于访问DBMS的网络平台组成。 虽然ODBC驱动器管理器的主要目的是加载数据库驱动器，以便ODBC函数调用，但是数据库驱动器本身也执行ODBC函数调用，并与数据库相互配合。因此当应用系统发出调用与数据源进行连接时，数据库驱动器能管理通信协议。当建立起与数据源的连接时，数据库驱动器便能处理应用系统向DBMS发出的请求，对分析或发自数据源的设计进行必要的翻译，并将结果返回给应用系统。 2．JDBC的诞生 自从Java语言于1995年5月正式公布以来，Java风靡全球。出现大量的用java语言编写的程序，其中也包括数据库应用程序。由于没有一个Java语言的API，编程人员不得不在Java程序中加入C语言的ODBC函数调用。这就使很多Java的优秀特性无法充分发挥，比如平台无关性、面向对象特性等。随着越来越多的编程人员对Java语言的日益喜爱，越来越多的公司在Java程序开发上投入的精力日益增加，对java语言接口的访问数据库的API 的要求越来越强烈。也由于ODBC的有其不足之处，比如它并不容易使用，没有面向对象的特性等等，SUN公司决定开发一Java语言为接口的数据库应用程序开发接口。在JDK1．x 版本中，JDBC只是一个可选部件，到了JDK1．1公布时，SQL类包（也就是JDBCAPI）
本科毕业设计文献综述范例(1)
###大学 本科毕业设计（论文）文献综述 课题名称： 学院（系）： 年级专业： 学生姓名： 指导教师： 完成日期：
燕山大学本科生毕业设计（论文） 一、课题国内外现状 中厚板轧机是用于轧制中厚度钢板的轧钢设备。在国民经济的各个部门中广泛的采用中板。它主要用于制造交通运输工具（如汽车、拖拉机、传播、铁路车辆及航空机械等）、钢机构件（如各种贮存容器、锅炉、桥梁及其他工业结构件）、焊管及一般机械制品等［1~3］。 1 世界中厚板轧机的发展概况 19世纪五十年代，美国用采用二辊可逆式轧机生产中板。轧机前后设置传动滚道，用机械化操作实现来回轧制，而且辊身长度已增加到2m以上，轧机是靠蒸汽机传动的。1864年美国创建了世界上第一套三辊劳特式中板轧机，当时盛行一时，推广于世界。1918年卢肯斯钢铁公司科茨维尔厂为了满足军舰用板的需求，建成了一套5230mm四辊式轧机，这是世界上第一套5m以上的轧机。1907年美国钢铁公司南厂为了轧边，首次创建了万能式厚板轧机，于1931年又建成了世界上第一套连续式中厚板轧机。欧洲国家中厚板生产也是较早的。1910年，捷克斯洛伐克投产了一套4500mm二辊式厚板轧机。1940年，德国建成了一套5000mm四辊式厚板轧机。1937年，英国投产了一套3810mm中厚板轧机。1939年，法国建成了一套4700mm 四辊式厚板轧机。这些轧机都是用于生产机器和兵器用的钢板，多数是为了二次世界大战备战的需要。1941年日本投产了一套5280mm四辊式厚板轧机，主要用于满足海军用板的需要。20世纪50年代，掌握了中厚板生产的计算机控制。20世纪80年代，由于中厚板的使用部门萧条，许多主要产钢国家的中厚板产量都有所下降，西欧国家、日本和美国关闭了一批中厚板轧机（宽度一般在3、4米以下）。国外除了大的厚板轧机以外，其他大型的轧机已很少再建。1984年底，法国东北方钢铁联营敦刻尔克厂在4300mm轧机后面增加一架5000mm宽厚板轧机，增加了产量，且扩大了品种。1984年底，苏联伊尔诺斯克厂新建了一套5000mm宽厚板轧机，年产量达100万t。1985年初，德国迪林冶金公司迪林根厂将4320mm轧机换成4800mm 轧机，并在前面增加一架特宽得5500mm轧机。1985年12月日本钢管公司福山厂新型制造了一套4700mmHCW型轧机，替换下原有得轧机，更有效地控制板形，以提高钢板的质量。 - 2 -
机械专业毕业论文外文翻译
附录一英文科技文献翻译 英文原文： Experimental investigation of laser surface textured parallel thrust bearings Performance enhancements by laser surface texturing (LST) of parallel-thrust bearings is experimentally investigated. Test results are compared with a theoretical model and good correlation is found over the relevant operating conditions. A compari- son of the performance of unidirectional and bi-directional partial-LST bearings with that of a baseline, untextured bearing is presented showing the bene?ts of LST in terms of increased clearance and reduced friction. KEY WORDS: ?uid ?lm bearings, slider bearings, surface texturing 1. Introduction The classical theory of hydrodynamic lubrication yields linear (Couette) velocity distribution with zero pressure gradients between smooth parallel surfaces under steady-state sliding. This results in an unstable hydrodynamic ?lm that would collapse under any external force acting normal to the surfaces. However, experience shows that stable lubricating ?lms can develop between parallel sliding surfaces, generally because of some mechanism that relaxes one or more of the assumptions of the classical theory. A stable ?uid ?lm with su?cient load-carrying capacity in parallel sliding surfaces can be obtained, for example, with macro or micro surface structure of di?erent types. These include waviness [1] and protruding microasperities [2–4]. A good literature review on the subject can be found in Ref. [5]. More recently, laser surface texturing (LST) [6–8], as well as inlet roughening by longitudinal or transverse grooves [9] were suggested to provide load capacity in parallel sliding. The inlet roughness concept of Tonder [9] is based on ??e?ective clearance‘‘ reduction in the sliding direction and in this respect it is identical to the par- tial-LST concept described in ref. [10] for generating hydrostatic e?ect in high-pressure mechanical seals. Very recently Wang et al. [11] demonstrated experimentally a doubling of the load-carrying capacity for the surface- texture design by reactive ion etching of SiC
机械毕业设计英文外文翻译588柱塞式液压缸、起重器和柱塞
附录A译文 (一) 柱塞式液压缸、起重器和柱塞 液压缸、起重器和柱塞的基本术语可以被看作为同义词。通常首先描述的是其基本质特征，“jack”通常用来描述，应用于起重器中的液压缸，而且在大多数应用驱动器的特定工业场合来提供起重装置，“ram”经常被应用于高输出力的大型、重型液压缸，其它一些权威书籍可能将“ram”定义为活塞和杆是相同直径的液压缸，尽管这种液压缸更准确的应该被叫做柱塞式油缸，或置换式液压缸，这些形式的液压缸单一作用式并有其相对的应用局限。 液压缸可为单作用式，在单作用液压缸情况下，运动由弹簧或某种外力或重力使活塞返回到起始位置时释放压力来完成，在这种情况下弹簧返回，再液压条件下可获得的输出力可以被弹簧抗力所减轻。 双作用液压缸再普通应用场合是最常用的，液流上被安装液压缸两端，被选择器交替实现输入口，输出口作用。最大的可获得的输出的仅比单作用液压缸所获得的输出稍小些，因为当液体压力被反向加压时组织泄露，因而增加了摩擦力抵抗运动。 在反向运动时，可获得的力会由于活塞和杆面积的不同而降低了活塞作用面积减少，反向压力也是存在的，这种性能损失也许会很小，但在实际中明显地减少理论性能，而且液压缸的理论性能是有一定规格的，允许的公称公差以适应摩擦损失。 大多数的液压缸是单杆式的，双杆式的液压缸可能被应用在要求特高刚度下。对于双作用式液压缸，冲压力在伸出和缩回是相等的，这里可以估计到相比在相同直径的液压缸由于杆的封闭作用，摩擦力也会两端的密封杆和密封轴承而增大。 液压缸被广泛用于工业液体系统中，这些液压缸也别称为线性原动机或往复原动机。通常液压缸由循环管，活塞和杆运动处两侧的密封组织，活塞杆可被设计在液压缸的一侧或两侧，围绕活塞杆向液压缸外的液体温度可以由正确设计的还有密封垫用途的应用。再这当中我们将学习各种类型的液压缸以及它们是如何应用的液压缸的用途会对工业水利学的学习有很大帮助。
软件开发概念和设计方法大学毕业论文外文文献翻译及原文
毕业设计（论文）外文文献翻译 文献、资料中文题目：软件开发概念和设计方法文献、资料英文题目： 文献、资料来源： 文献、资料发表（出版）日期： 院（部）： 专业： 班级： 姓名： 学号： 指导教师： 翻译日期： 2017.02.14
外文资料原文 Software Development Concepts and Design Methodologies During the 1960s, ma inframes and higher level programming languages were applied to man y problems including human resource s yste ms,reservation s yste ms, and manufacturing s yste ms. Computers and software were seen as the cure all for man y bu siness issues were some times applied blindly. S yste ms sometimes failed to solve the problem for which the y were designed for man y reasons including: ?Inability to sufficiently understand complex problems ?Not sufficiently taking into account end-u ser needs, the organizational environ ment, and performance tradeoffs ?Inability to accurately estimate development time and operational costs ?Lack of framework for consistent and regular customer communications At this time, the concept of structured programming, top-down design, stepwise refinement，and modularity e merged. Structured programming is still the most dominant approach to software engineering and is still evo lving. These failures led to the concept of "software engineering" based upon the idea that an engineering-like discipl ine could be applied to software design and develop ment. Software design is a process where the software designer applies techniques and principles to produce a conceptual model that de scribes and defines a solution to a problem. In the beginning, this des ign process has not been well structured and the model does not alwa ys accurately represent the problem of software development. However,design methodologies have been evolving to accommo date changes in technolog y coupled with our increased understanding of development processes. Whereas early desig n methods addressed specific aspects of the
毕业设计文献综述范文
四川理工学院毕业设计（文献综述）红外遥控电动玩具车的设计 学生：程非 学号：10021020402 专业：电子信息工程 班级：2010.4 指导教师：王秀碧 四川理工学院自动化与电子信息学院 二○一四年三月
1前言 1.1 研究方向 随着科技的发展，越来越多的现代化电器走进了普通老百姓的家庭，而这些家用电器大都由红外遥控器操控，过多不同遥控器的混合使用带来了诸多不便。因此，设计一种智能化的学习型遥控器，学习各种家用电器的遥控编码，实现用一个遥控器控制所有家电，已成为迫切需求。首先对红外遥控接收及发射原理进行分析，通过对红外编码理论的学习，设计以MSP430单片机为核心的智能遥控器。其各个模块设计如下：红外遥控信号接收，红外接收器把接收到的红外信号经光电二极管转化成电信号，再对电信号进行解调，恢复为带有一定功能指令码的脉冲编码；接着是红外编码学习，利用单片机的输入捕捉功能捕捉载波的跳变沿，并通过定时器计时记下载波的周期和红外信号的波形特征，进行实时编码；存储电路设计，采用I2C总线的串行E2PROM(24C256)作为片外存储器，其存储容量为8192个字节，能够满足所需要的存取需求；最后是红外发射电路的设计，当从存储模块中获取某红外编码指令后，提取红外信号的波形特征信息并进行波形还原；将其调制到38KHZ的载波信号上，通过三极管放大电路驱动红外发光二极管发射红外信号，达到红外控制的目的。目前，国外进口的万能遥控器价格比较昂贵，还不能真正走进普通老百姓的家中。本文在总结和分析国外设计的基础上，设计一款以MSP430单片机为核心的智能型遥控器，通过对电视机和空调的遥控编码进行学习，能够达到预期的目的，具有一定的现实意义。 1.2 发展历史 红外遥控由来已久，但是进入90年代，这一技术又有新的发张，应用范围更加广泛。红外遥控是一种无线、非接触控制技术，具有抗干扰能力强，信息传输可靠，功耗低，成本低，易实现等显著优点，被诸多电子设备特别是家用电器广泛采用，并越来越多的应用到计算机系统中。 60年代初，一些发达国家开始研究民用产品的遥控技术，单由于受当时技术条件限制，遥控技术发展很缓慢，70年代末，随着大规模集成电路和计算机技术的发展，遥控技术得到快速发展。在遥控方式上大体经理了从有线到无限的超声波，从振动子到红外线，再到使用总线的微机红外遥控这样几个阶段。无论采用何种方式，准确无误传输新信号，最终达到满意的控制效果是非常重要的。最初的无线遥控装置采用的是电磁波传输信号，由于电磁波容易产生干扰，也易受干扰，因此逐渐采用超声波和红外线媒介来传输信号。与红外线相比，超声传感器频带窄，所能携带的信息量少扰而引起误动作。较为理想的是光控方式，逐渐采用红外线的遥控方式取代了超声波遥控方式，出现了红外线多功能遥控器，成为当今时代的主流。 1.3 当前现状 红外线在频谱上居于可见光之外，所以抗干扰性强，具有光波的直线传播特性，不易产生相互间的干扰，是很好的信息传输媒体。信息可以直接对红外光进行调制传输，例如，信息直接调制红外光的强弱进行传输，也可以用红外线产生一定频率的载波，再用信息对载波进调制，接收端再去掉载波，取到信息。从信
机械类毕业设计外文翻译
本科毕业论文(设计) 外文翻译 学院：机电工程学院 专业：机械工程及自动化 姓名：高峰 指导教师：李延胜 2011年05 月10日 教育部办公厅 Failure Analysis，Dimensional Determination And
Analysis，Applications Of Cams INTRODUCTION It is absolutely essential that a design engineer know how and why parts fail so that reliable machines that require minimum maintenance can be designed．Sometimes a failure can be serious，such as when a tire blows out on an automobile traveling at high speed．On the other hand，a failure may be no more than a nuisance．An example is the loosening of the radiator hose in an automobile cooling system．The consequence of this latter failure is usually the loss of some radiator coolant，a condition that is readily detected and corrected．The type of load a part absorbs is just as significant as the magnitude．Generally speaking，dynamic loads with direction reversals cause greater difficulty than static loads，and therefore，fatigue strength must be considered．Another concern is whether the material is ductile or brittle．For example，brittle materials are considered to be unacceptable where fatigue is involved． Many people mistakingly interpret the word failure to mean the actual breakage of a part．However，a design engineer must consider a broader understanding of what appreciable deformation occurs．A ductile material，however will deform a large amount prior to rupture．Excessive deformation，without fracture，may cause a machine to fail because the deformed part interferes with a moving second part．Therefore，a part fails(even if it has not physically broken)whenever it no longer fulfills its required function．Sometimes failure may be due to abnormal friction or vibration between two mating parts．Failure also may be due to a phenomenon called creep，which is the plastic flow of a material under load at elevated temperatures．In addition，the actual shape of a part may be responsible for failure．For example，stress concentrations due to sudden changes in contour must be taken into account．Evaluation of stress considerations is especially important when there are dynamic loads with direction reversals and the material is not very ductile． In general，the design engineer must consider all possible modes of failure，which include the following． ——Stress ——Deformation ——Wear ——Corrosion ——Vibration ——Environmental damage ——Loosening of fastening devices
毕业设计外文翻译附原文
外文翻译 专业机械设计制造及其自动化学生姓名刘链柱 班级机制111 学号1110101102 指导教师葛友华
外文资料名称： Design and performance evaluation of vacuum cleaners using cyclone technology 外文资料出处：Korean J. Chem. Eng., 23(6), (用外文写) 925-930 (2006) 附件： 1.外文资料翻译译文 2.外文原文
应用旋风技术真空吸尘器的设计和性能介绍 吉尔泰金，洪城铱昌，宰瑾李， 刘链柱译 摘要：旋风型分离器技术用于真空吸尘器 - 轴向进流旋风和切向进气道流旋风有效地收集粉尘和降低压力降已被实验研究。优化设计等因素作为集尘效率，压降，并切成尺寸被粒度对应于分级收集的50％的效率进行了研究。颗粒切成大小降低入口面积，体直径，减小涡取景器直径的旋风。切向入口的双流量气旋具有良好的性能考虑的350毫米汞柱的低压降和为1.5μm的质量中位直径在1米3的流量的截止尺寸。一使用切向入口的双流量旋风吸尘器示出了势是一种有效的方法，用于收集在家庭中产生的粉尘。 摘要及关键词：吸尘器; 粉尘; 旋风分离器 引言 我们这个时代的很大一部分都花在了房子，工作场所，或其他建筑，因此，室内空间应该是既舒适情绪和卫生。但室内空气中含有超过室外空气因气密性的二次污染物，毒物，食品气味。这是通过使用产生在建筑中的新材料和设备。真空吸尘器为代表的家电去除有害物质从地板到地毯所用的商用真空吸尘器房子由纸过滤，预过滤器和排气过滤器通过洁净的空气排放到大气中。虽然真空吸尘器是方便在使用中，吸入压力下降说唱空转成比例地清洗的时间，以及纸过滤器也应定期更换，由于压力下降，气味和细菌通过纸过滤器内的残留粉尘。 图1示出了大气气溶胶的粒度分布通常是双峰形，在粗颗粒（>2.0微米）模式为主要的外部来源，如风吹尘，海盐喷雾，火山，从工厂直接排放和车辆废气排放，以及那些在细颗粒模式包括燃烧或光化学反应。表1显示模式，典型的大气航空的直径和质量浓度溶胶被许多研究者测量。精细模式在0.18?0.36 在5.7到25微米尺寸范围微米尺寸范围。质量浓度为2?205微克，可直接在大气气溶胶和 3.85至36.3μg/m3柴油气溶胶。
模具毕业设计外文翻译(英文+译文)
Injection Molding The basic concept of injection molding revolves around the ability of a thermoplastic material to be softened by heat and to harden when cooled .In most operations ,granular material (the plastic resin) is fed into one end of the cylinder (usually through a feeding device known as a hopper ),heated, and softened(plasticized or plasticized),forced out the other end of the cylinder, while it is still in the form of a melt, through a nozzle into a relatively cool mold held closed under pressure.Here,the melt cools and hardens until fully set-up. The mold is then opened, the piece ejected, and the sequence repeated. Thus, the significant elements of an injection molding machine become: 1) the way in which the melt is plasticized (softened) and forced into the mold (called the injection unit); 2) the system for opening the mold and closing it under pressure (called the clamping unit);3) the type of mold used;4) the machine controls. The part of an injection-molding machine, which converts a plastic material from a sold phase to homogeneous seni-liguid phase by raising its temperature .This unit maintains the material at a present temperature and force it through the injection unit nozzle into a mold .The plunger is a combination of the injection and plasticizing device in which a heating chamber is mounted between the plunger and mold. This chamber heats the plastic material by conduction .The plunger, on each stroke; pushes unbelted plastic material into the chamber, which in turn forces plastic melt at the front of the chamber out through the nozzle The part of an injection molding machine in which the mold is mounted, and which provides the motion and force to open and close the mold and to hold the mold close with force during injection .This unit can also provide other features necessary for the effective functioning of the molding operation .Moving
本科毕业设计方案外文翻译范本
I / 11 本科毕业设计外文翻译 <2018届） 论文题目基于WEB 的J2EE 的信息系统的方法研究 作者姓名[单击此处输入姓名] 指导教师[单击此处输入姓名] 学科(专业 > 所在学院计算机科学与技术学院 提交日期[时间 ]
基于WEB的J2EE的信息系统的方法研究 摘要：本文介绍基于工程的Java开发框架背后的概念，并介绍它如何用于IT 工程开发。因为有许多相同设计和开发工作在不同的方式下重复，而且并不总是符合最佳实践，所以许多开发框架建立了。我们已经定义了共同关注的问题和应用模式，代表有效解决办法的工具。开发框架提供：<1）从用户界面到数据集成的应用程序开发堆栈；<2）一个架构，基本环境及他们的相关技术，这些技术用来使用其他一些框架。架构定义了一个开发方法，其目的是协助客户开发工程。 关键词：J2EE 框架WEB开发 一、引言 软件工具包用来进行复杂的空间动态系统的非线性分析越来越多地使用基于Web的网络平台，以实现他们的用户界面，科学分析，分布仿真结果和科学家之间的信息交流。对于许多应用系统基于Web访问的非线性分析模拟软件成为一个重要组成部分。网络硬件和软件方面的密集技术变革[1]提供了比过去更多的自由选择机会[2]。因此，WEB平台的合理选择和发展对整个地区的非线性分析及其众多的应用程序具有越来越重要的意义。现阶段的WEB发展的特点是出现了大量的开源框架。框架将Web开发提到一个更高的水平，使基本功能的重复使用成为可能和从而提高了开发的生产力。 在某些情况下，开源框架没有提供常见问题的一个解决方案。出于这个原因，开发在开源框架的基础上建立自己的工程发展框架。本文旨在描述是一个基于Java的框架，该框架利用了开源框架并有助于开发基于Web的应用。通过分析现有的开源框架，本文提出了新的架构，基本环境及他们用来提高和利用其他一些框架的相关技术。架构定义了自己开发方法，其目的是协助客户开发和事例工程。 应用程序设计应该关注在工程中的重复利用。即使有独特的功能要求，也
信工学院毕业设计外文翻译封面完整版
信工学院毕业设计外文 翻译封面 Document serial number【NL89WT-NY98YT-NC8CB-NNUUT-NUT108】
毕业设计外文资料翻译 专业名称网络工程 班级学号 学生姓名吕帅 指导教师胡硕 填表日期 2015 年 04 月 02 日 Cryptography isone ofthe maintraditional technology andinformation security technology,it is theShannoninformation theory andcryptography theory andtechnology based on thedigital content protection,theuse ofencryptionmethod to complete,i.e.themultimediadata fileis encrypted into ciphertextafter the release,theillegal attackerappearsin the transmission processcannot obtainconfidentialinformation from thetext,so as to achievethe purpose ofcopyright protection andinformation security.Butthis does not completely solve the problem: the spread ofanencrypted filebecause it is notcomprehensibleand hinderthe multimedia information;on the other hand,through themultimedia informationencryptionis easy to causethe attacker'sattention and curiosity,andthere isthe possibility of cracking,and when theinformation isreceivedanddecrypted,theencryptionthe documentandthe document,will no longer be protected,not spared frompiracy.In other words,cryptographycan protectthe transmissionofcontent,and the contentoncedecryptionwill no longer have theprotection.Therefore,there is an urgent need for areplacementorsupplement thecryptographytechnology,itevencan continue to protect thecontent is decryptedincontent.In this way,people put forward thenewconcept ofdigital watermarking,information hiding.Digital watermark isa new direction in thefield of information security technology,is anewtechnologyto protectcopyright and authentication source andintegrality in theopen network environment,the creation ofinformation andpersonal logocreatorthrough digitalwatermarking system toembed the watermarkcan not be perceivedbypeoplein themedia,peoplecan not perceiveon the face ofthe watermark,onlyspecial detector orcomputer softwarethatcan detect thedigital watermarkhidden.
机械类毕业设计外文文献翻译
沈阳工业大学工程学院 毕业设计（论文）外文翻译 毕业设计（论文）题目：工具盒盖注塑模具设计 外文题目：Friction , Lubrication of Bearing 译文题目：轴承的摩擦与润滑 系（部）：机械系 专业班级：机械设计制造及其自动化0801 学生姓名：王宝帅 指导教师：魏晓波 2010年10 月15 日
外文文献原文： Friction , Lubrication of Bearing In many of the problem thus far , the student has been asked to disregard or neglect friction . Actually , friction is present to some degree whenever two parts are in contact and move on each other. The term friction refers to the resistance of two or more parts to movement. Friction is harmful or valuable depending upon where it occurs. friction is necessary for fastening devices such as screws and rivets which depend upon friction to hold the fastener and the parts together. Belt drivers, brakes, and tires are additional applications where friction is necessary. The friction of moving parts in a machine is harmful because it reduces the mechanical advantage of the device. The heat produced by friction is lost energy because no work takes place. Also , greater power is required to overcome the increased friction. Heat is destructive in that it causes expansion. Expansion may cause a bearing or sliding surface to fit tighter. If a great enough pressure builds up because made from low temperature materials may melt. There are three types of friction which must be overcome in moving parts: (1)starting, (2)sliding, and(3)rolling. Starting friction is the friction between two solids that tend to resist movement. When two parts are at a state of rest, the surface irregularities of both parts tend to interlock and form a wedging action. To produce motion in these parts, the wedge-shaped peaks and valleys of the stationary surfaces must be made to slide out and over each other. The rougher the two surfaces, the greater is starting friction resulting from their movement . Since there is usually no fixed pattern between the peaks and valleys of two mating parts, the irregularities do not interlock once the parts are in motion but slide over each other. The friction of the two surfaces is known as sliding friction. As shown in figure ,starting friction is always greater than sliding friction . Rolling friction occurs when roller devces are subjected to tremendous stress which cause the parts to change shape or deform. Under these conditions, the material in front of a roller tends to pile up and forces the object to roll slightly uphill. This changing of shape , known as deformation, causes a movement of molecules. As a result ,heat is produced from the added energy required to keep the parts turning and overcome friction. The friction caused by the wedging action of surface irregularities can be overcome