【正文】 小，會進(jìn)一步減弱軸的強(qiáng)度。2 、If this workpiece is held between the centers of the lathe, the centers exert a pressive force against the work. 如果這個工件在放在車床中心之間,中心車床對工作產(chǎn)生壓力。力偶臂是這兩個條作用線之間的垂直距離，力偶面是包含著兩條作用線的平面。Any two such forces acting on a body constitute a couple. The arm of the couple is the perpendicular distance between their lines of action, and the plane of the couple is the plane containing the two lines of action.作用在一個剛體上的兩個這樣的的里構(gòu)成一個力偶。figure1(如圖)。在鍵及軸上與之相對應(yīng)的鍵槽的設(shè)計中，必須進(jìn)行認(rèn)真的計算。The importance of fasteners can be realized when referring ro any plex product,In the case of the automobile,there are literally thousands of parts which are fastened together to produce the total failure or loosening of a single fastener could result in a simple nuisance such as a door rattle or in a serious situation such as a wheel ing off.Such possibilities must be taken into account in the selection of the type of fatener for the specific application.通過任何一個復(fù)雜的產(chǎn)品，都可以認(rèn)識到緊固件在其中的重要性。 The fit of the bearing races onto the shaft or onto the housing is of critical importance because of their bined effect on the internal clearance of the bearing as well as preserving the desired degree of interference fit.軸承套圈與軸或軸承座的的配合非常重要，因為它們之間的配合不僅應(yīng)該保證所需要的過盈量，而且也應(yīng)該保證軸承的內(nèi)部間隙。這些試驗應(yīng)該在與所設(shè)計的零件有相同的熱處理，表面粗糙度和尺寸大小的試件進(jìn)行，而且試驗應(yīng)該在與零件使用過程中承受的載荷完全相同的情況下進(jìn)行。設(shè)計通?？梢苑譃閹讉€明確的階段；（a）概念設(shè)計；b 功能設(shè)計 c 生產(chǎn)設(shè)計。另外，還可以包含公差、審核人員和材料等信息。單詞 basic hole system 基孔制 basic shaft system 基軸制Leesson331Engineering and technology students must became puter literate, to understand the applications of puter and their advantages. Not to do so will place students at a serious disadvantage in pursuing their careers.工程技術(shù)專業(yè)的學(xué)生們應(yīng)該通曉計算機(jī)，了解計算機(jī)的用途和它們的優(yōu)點。machines with a wide variety of power feature of all turret lathes, however, is that the tools can perform a consecutive serials of operations in proper sequence. Once the tools have been set and adjusted ,little skill is required to turn out duplicate parts.高生產(chǎn)率的磚塔車床是裝有許多動力附件的非常復(fù)雜的機(jī)器。因為他們除了完成常規(guī)的車削工作之外，還可以完成某些銑削鉆削工作單詞：turret 磚塔，六角刀架，六角頭 general purpose 多方面的，多種用途的Lesson65 to the Tool amp。 ,GT helps to place the new part in an appropriate family .The standard plan is then edited to suit the specific requirements of a particular job.成組技術(shù)可以幫助把新零件歸類于適當(dāng)?shù)牧慵逯小?The development of the microprocessor allowed for the development of programmable logic controllers (PLCs) and microputer.微處理器的發(fā)展為可編程邏輯控制器和微型計算機(jī)的發(fā)展做好了準(zhǔn)備。機(jī)器人的這個系統(tǒng)應(yīng)該具有測出是否有需要自動停止工作的要求的能力。The term “multifunctional” means that the robot can,throughreprogramming and the use of different endeffectors ,preform a number of diferent manufacturing tasks .翻譯：“多功能”這個詞意味著機(jī)器人能夠通過編程和使用不同的末端執(zhí)行機(jī)構(gòu)，完成不同的制造工作。在數(shù)控技術(shù)出現(xiàn)之前，所有的機(jī)床都是有人工操作和控制的。 is primarily an informationhanding job ,and the puter is an ideal panion.這主要是一些信息處理工作，而計算機(jī)是完成這項工作的一個理想助手。With the single spndle machine, the turret indexes around the spindle.在單軸車床上，磚塔圍繞主軸轉(zhuǎn)位。其應(yīng)用從建立三維模型和有限元分析，直到繪制平面圖和進(jìn)行數(shù)字計算。A part is said to be at the least material condition (LMC) when the dimensions are all at the limits that give a part with the smallest amount of material. 當(dāng)所有的尺寸都處在允許零件含有的材料量為最小的極限狀態(tài)時，就稱這個零件處于最小實體狀態(tài)（LMC）。24/27課Working drawings are the drawings from which a design is implemented. All principles of orthographic projection and techniques of graphics can be used to municate the details of a project in working drawings. A detail drawing is a working drawing of a single part (or detail) within the set of working drawings. 工作圖是將設(shè)計變?yōu)閷嶋H產(chǎn)品所依據(jù)的圖樣。通?？梢灾苯釉趯嶋H的機(jī)械零件上進(jìn)行硬度試驗。Where life is not the determing factor in design ,it is usual to determine maximum loading by the amount to which a bearing will deflect under load .在使用壽命不是設(shè)計中的決定因素的場合，通常根據(jù)軸承受載荷時產(chǎn)生的變形量來確定其最大載荷。Less