【正文】 system in the organization and future needs.Working Procedures: The working procedures are basically served as organization/project custom made standardization and need to be known and implemented throughout the project from the top level to the last subcontractor. They should be adjusted to maintain good levels of control without producing unnecessary bureaucracies. The procedure should take into account the following:(a)What data needs to be controlled. (b) The level of standardization for each data item. (c) The data flow process. (d) The management levels for data release approval. Controlled data can include: (a) Full detailed CAD assembly. (b) Integration level assembly less detailed system assembly and Interface Control Documents (ICD).(c) System versions: customized versions, training versions, tests versions, reduced functionality systems versions, etc. (d) Analysis models: model and assembly versions that were adjusted transferred to analysis personnel, like FEA, CFD, dynamic response, thermal analysis, antenna response, etc.The level of standardization can be changed according to the level of integration of the data and the plexity of the interfaces: from the top level of the system main chassis or main wiring that are integrated with many ponents and should be most strictly controlled。 later, the timing can be changed up to upon demand. (c) Data file format standards, like CAD, STEP, WORD, PDF, etc. (d) Level of details: full CAD assembly, ICDs only, one part solid assembly, etc. This takes into account considerations of time and effort for building the models, mercial restrictions, security and logical approach. For instance, the detailed assembly of the aircraft seats would only interfere with the engine pylon design。D 中心海法, 以色列yuvalb管理機械數(shù)據(jù)庫摘要發(fā)展復雜的系統(tǒng)通常包括許多活動，建立在CAD模型制造集成的基礎(chǔ)上，如：機械裝配，分析模型，接口控制，刀具，夾具制造，生產(chǎn)模型，質(zhì)量性質(zhì)，儀表，記錄技術(shù)等等。另一方面，不合理的采用集成數(shù)據(jù)庫會在制造過程和機械裝配中引發(fā)很大的錯誤，它可能導致時間，金錢和名譽上的損失。機械積分器保證生產(chǎn)過程順利的執(zhí)行通過第二制造系統(tǒng)，也就是說當前的設計是建立在準許的數(shù)據(jù)上，類屬部件的使用以及其它更多是通過管理更新的和堅固的數(shù)據(jù)庫而建立的。引言當前的商業(yè)和技術(shù)環(huán)境推動工程方法變得更加有效率，柔性系統(tǒng)越來越快，市場條件瞬息變化，全球鄉(xiāng)村和補償協(xié)議轉(zhuǎn)換成技巧為了縮短整體的制造時間和制造力，這做的主要通過類屬部件和模塊在制造的基礎(chǔ)上，全系統(tǒng)分割成第二制造系統(tǒng)和作業(yè)包裝，可同時實現(xiàn)協(xié)議通過不同的制造團使用不同的方法和工具在不同的區(qū)域定位和培養(yǎng)。另一方面，有效地和精確的集成能力比以前更有針對性。在將來，據(jù)合理的估計所有的數(shù)據(jù)庫將集成在一個中心的數(shù)據(jù)庫包括——附加一個普通的CAD文檔；配線模型，裝配過程，機械手冊，市場數(shù)據(jù)和天然的更新產(chǎn)品版本。為了滿足上述解釋的需要，下面推薦幾個不同階層調(diào)整后的基礎(chǔ)機構(gòu)：(a)人員訓練(b)分承包人訓練和質(zhì)量鑒定(c)技術(shù)環(huán)境(d)生產(chǎn)過程人員訓練：機械積分訓練基于分析它的活動和職責，且能夠適應工程復雜形勢的改變。這總不能被最后部件設計者所接受。為了達到完美的合作，需要解釋他們需求的重要性，來訓練他們，以達到訓練他們?nèi)绾瓮ㄟ^流程來工作并且監(jiān)測數(shù)據(jù)庫的傳輸。一個合格的分承包人比一個不合格的分承包人在交流協(xié)商中有很多優(yōu)點。技術(shù)環(huán)境當使用合適的數(shù)據(jù)管理軟件時，有效地控制大量的數(shù)據(jù)庫變得更加簡單。生產(chǎn)流程生產(chǎn)流程是一個基準，它貫穿到一個工程從最高起點到最后的分承包人。數(shù)據(jù)庫的浮動工序被建立在生產(chǎn)模型的準則的基礎(chǔ)上，規(guī)定如下：（a）數(shù)據(jù)被轉(zhuǎn)移給誰，通過數(shù)據(jù)庫流程圖（解釋下一段）（b）作為數(shù)據(jù)庫里程碑傳輸基本的工程情況：在第一階段，數(shù)據(jù)庫傳輸將會很頻繁（從每天到逐漸增加到許多星期）。這將引入考慮時間和建立模型，商業(yè)限制，安全和邏輯方法的作用。一個數(shù)據(jù)庫流程圖的例子如表表2所示表1 系統(tǒng)裝配表格表1展示的系統(tǒng)裝配表格建立在亞系統(tǒng)的的階層，通常依賴于系統(tǒng)模型樹。數(shù)據(jù)高低的浮動能建立在ICDs模型，它能直接反射出當前系統(tǒng)的約束，而且高端數(shù)據(jù)的浮動通常包含完美裝配模型，基于ICD模型。表2 系統(tǒng)數(shù)據(jù)浮動過程二、GEAR AND SHAFT INTRODUCTIONIn the force analysis of spur gears, the forces are assumed to act in a single plane. We shall study gears in which the forces have three dimensions. The reason for this, in the case of helical gears, is that the teeth are not parallel to the axis of rotation. And in the case of bevel gears, the rotational axes are not parallel to each other. There are also other reasons, as we shall learn.Helical gears are used to transmit motion between parallel shafts. The helix angle is the same on each gear, but one gear must have a righthand helix and the other a lefthand helix. The shape of the tooth is an involute helicoid. If a piece of paper cut in the shape of a parallelogram is wrapped around a cylinder, the angular edge of the paper bees a helix. If we unwind this paper, each point on the angular edge generates an involute curve. The surface obtained when every point on the edge generates an involute is called an involute helicoid.The initial contact of spurgear teeth is a line extending all the way across the face of the tooth. The initial contact of helical gear teeth is a point, which changes into a line as the teeth e into more engagement. In spur gears the line of contact is parallel to the axis of the rotation。 that is ,a righthand driver goes with a righthand driven. In the design of crossedhelical gears, the minimum sliding velocity is obtained when the helix angle are equal. However, when the helix angle are not equal, the gear with the larger helix angle should be used as the driver if both gears have the same hand.Worm gears are similar to crossed helical gears. The pinion or worm has a small number of teeth, usually one to four, and since they pletely wrap around the pitch cylinder they are called threads. Its mating gear is called a worm gear, which is not a true helical gear. A worm and worm gear are used to provide a high angularvelocity reduction between nonintersecting shafts which are usually at right angle. The worm gear is not a helical gear because its face is made concave to fit the curvature of the worm in order to provide line contact instead of point contact. However, a disadvantage of worm gearing is the high sliding velocities across the teeth, the same as with crossed helical gears.Worm gearing are either single or double enveloping. A singleenveloping gearing is one in which the gear wraps around or partially encloses the worm.. A gearing in which each element partially encloses the other is, of course, a doubleenveloping worm gearing. The important difference between the two is that area contact exists between the teeth of doubleenveloping gears while only line contact between those of singleenveloping gears. The worm and worm gear of a set have the same hand of helix as for crossed helical gears, but the helix angles are usually quite different. The helix angle on the worm is generally quite large, and that on the gear very small. Because of this, it is usual to specify the lead angle on the worm, which is the plement of the worm helix angle, and the helix angle on the gear