机械工程专业英语复习资料.docx

1.1 Suppose that , to accomplish the speed reduction ,you decide a double-reduction ,spur gear speed reducer .You specify four gears ,three shafts ,six bearings ,and a housing to hold the individual elements in proper relation to each other .假如要完成一个两级直齿圆柱齿轮减速器的设计，确定有四个齿轮、三根轴、六个轴承和容纳这些零件并使它们彼此之间保持它们正确位置关系的箱体。1.2 Each of the three shafts is supported by ball bearings ,making them statically determinate and allowing analysis of forces and stresses using standard principles of mechanics .三根轴中的每根轴都由一对球轴承支承固定，使其静态稳定可运用力学原理来进行载荷和应力分析1.3 The input and output shafts will extend beyond the housing to permit coupling with the engine and the drive axle.输入轴和输出轴要延伸至箱体外来与发动机和驱动轴相连。2.1 The driving teeth push on the driven teeth exerting a force perpendicular to the radius of the gear.主动轮齿推动从动轮齿，在垂直于齿轮半径方向上施加作用力。2.2 From the moment of initial contact to the moment of disengagement, the speed of the driving gear is in a constant proportion to the speed of the driven gear .从最初接触一直到分开，主动轮的速度与从动轮的速度的比值是恒定的。2.3 The parallel shaft arrangement for helical gears is because it results in a much higher power-transmitting capacity for a given size of gear than the crossed helical arrangement .对于斜齿轮来说，应优先选用平行轴安装方式，因为对于同样尺寸的齿轮而言，平行轴安装方式比交错轴斜齿轮安装方式传递效率高很多。3.1 A key is the machinery component placed at the interface between a shaft and hub of a power-transmitting element for the purpose transmitting torque .键是安装在轴和轮毂结合处的机械零件，作用是传递扭矩和动力。3.2 The load path is then from the driving shaft to its flange ,through the bolts ,into the mating flange ,and out to the driven shaft .载荷从主动轴加载到法兰上，然后通过螺栓加载到与之配合的另一个法兰上，在传递给从动轴。3.3 Flexible couplings are designed to transmit torque smoothly while permitting some axial ,radial ,and angular misalignment. The flexibility such that when misalignment does occur ,parts of the coupling move with little or no resistance.柔性联轴器设计要求平滑地传递扭矩，允许少许的轴向、径向和角度误差。因为存在柔性，当误差发生时联轴器中的零件可在微小的甚至无阻力下移动校正。4.1 The term rolling contact bearings refers to the wide variety of bearings that use spherical balls or some other type of roller between the stationary and the moving elements .滚动接触轴承指的是在固定和运动零件之间使用球轴承或者其他类型滚动体的大类轴承4.2 Usually the outer race is stationary and is held by the housing of the machine. The inner race is pressed onto the rotating shaft and thus rotates with it .通常外圈固定在结构的箱体孔内，内圈与旋转轴连接并随之转动。4.3 To increase the capacity of a single-row bearing , a bearing with a greater number of balls operating in larger-row bearing with a greater number of balls ,or larger balls operating in larger-diameter races should be used . 为增加单列轴承的承载能力，会采用更多数量的滚珠或是让较大的滚珠运转在较大直径的套圈内。5.1 Rotary power is developed by the electric motors , but motors typically operate at too high a speed and deliver too low a torque to be appropriate for the final drive application. Remember, for a given power transmission , the torque is increased in proportion to the amount that rotational speed is reduced .旋转功率由电动机提供，但由于电动机的输出转速很高，输出的扭矩很低，所以电动机不适合于驱动装置直接连接。对一定的动力而言，扭矩增加与转速下降成正比5.2 When belt is used for speed reduction ,the typical case ,the smaller sheave is mounted on the high-speed shaft ,such as the shaft of an electric motor .The larger sheave is mounted on the driven machine .当传动带用于减速时，通常较小的带轮安装在高速轴端，较大的带轮安装在被驱动装置上。5.3 When transmitting power between rotating shaft, the chain engages mating toothed wheels , called sprockets .当在旋转轴之间传递动力时，链条与链轮啮合链轮上带有啮合的结构。6.1The former is necessary in order to enable the drive to be taken up gradually and smoothly , while the latter provides different ratios of speed reduction from the engine to the wheels ,to suit the particular conditions of running.摩擦离合器的功用是使行驶过程逐渐地、平缓地进行；而变速箱的功用是以不同的减速比将发动机速度传给车轮，完成特定的行驶条件。6.2After the driver release the clutch must act as solid coupling device .It must transmit all engine power to the transmission ,without slipping.驾驶员踩下离合器踏板对传动装置内的齿轮进行换挡，当驾驶员抬起离合器踏板时，离合器必须起到像刚性联轴器一样的作用，即它能将所有的动力传递到传动装置中并不产生打滑。6.3 A driver shifts or changes the gears to increase or decrease the torque produced by the engine .In a car with a manual gearbox a driver shifts the gears manually .In a car with an automatic gearbox ,the gears shift automatically.驾驶员改变或变换齿轮来增加或减小发动机的输出扭矩。具有手动变速箱的汽车需要手动变换齿轮。据有自动变速箱的汽车，齿轮自动换挡。7.1 Metric abbreviation after the numerals is omitted from dimensions because the SI symbol near the title block indicates that all units are metric.由于在标题栏附近的国际单位制符号标明所有单位为公制，因此尺寸数字后面单位缩写要省略标注。7.2 In practice ,title blocks usually contain the title or part name ,drafter ,date , scale , company ,and sheet number. Other information ,such as tolerances ,checkers ,and materials ,also may be given .实际上，标题栏通常包含标题或部件的名称、绘图员姓名、绘图日期、绘图比例、所属单位以及图纸编号。还有其他信息，如公差、审核人、材料等等，也应该在图纸上给出。7.3 They return the marked-up print to the drafter who revises the original and makes another print for final approval .他们将修改过的图纸返回给绘图员，为获得最终批准，绘图员对原图进行修正并重新晒图。8.1However ,it is almost impossible to produce any component to the exact dimension through any of the known manufacturing processes .Even if a component is perceived to be made to the exact dimension by the manual processes ,the actual measurement with a high resolution measuring device will show that it is not so.然而，用已知的任何一种制造方法都不可能使零件达到完全精准的尺寸。即使在手工方法加工时，感觉零件已达到精准的尺寸，但用高分辨率测量设备测量后发现并非如此。8.2In engineering ,when a product is designed it consists of parts and parts will be mating with each other in some form.工程应用中，当设计一个产品，该产品包含许多零部件，这些零部件将以一定的方式相互配合。8.3 In the ISO system of limits and fits ,for any given size ,a range of tolerances and deviations can be specified with reference to a line of zero deviation called the zero line . 极限配合的ISO体系中，对于任意给定的尺寸公差和偏差的范围可以用零偏差线为参照来定义。该线称为零线。9.1 Mechanical properties occur as a result of the physical properties inherent to each material ,and are determined through a series of standardized mechanical tests.对于任意材料而言，其力学性能都是由内部物理性质所决定的，并且可以通过一系列标准测试方法获得。9.2 Axial strain is always accompanied by lateral strains of opposite sign in the two directions mutually perpendicular to the axial strain.轴向应变总是伴随着符号相反、相互垂直于轴向的两个方向上的横向应变一同出现。9.3 Materials such as most plastics that do not rupture can have their result reported as the compressive strength at a specific deformation such as 1%,5%,or 10% of the samples original height.对于无法破坏的材料，如塑性材料等，可以定义其压缩强度为式样的变形达到其初始长度的1%、5%或10%时对应的应力值。10.1 This primitive device has evolved over the last two centuries to be one of the most fundamental and versatile machine tools with large variants ,to be one of the manufacturing shops.这个原始设备在最近的两个世纪已演变成最重要而且最普遍的机床，被广泛使用在所有的加工中。10.2The headstock is towards the left-end on the bed and is fixed to it , which houses the power source ,the power transmission ,gear box ,and the spindle.床头箱固结在床身的左端部，其中安装有电源、动力传输结构、齿轮箱和主轴。10.3This also houses the cross-slide for giving the motion to the cutting tool ,in a direction perpendicular to the axis of rotation, the compound-slide ,which provides an auxiliary slide to get the necessary special motion for special surface generations ,and the tool post, which allows mounting of the cutting tool.拖板上安装的横向滑板也为刀具提供了垂直于旋转轴的横向运动，复合式滑板也提供辅助性的滑动，这种滑动是为得到特定的运动表面所需的特定运动；刀架是用来安装切削刀具。1、speed reducer 减速器 gasoline engine 汽油发动机 bending torsion 弯矩和扭矩strength and rigidity强度和刚度 bevel gear 锥齿轮 worm and worm gear 涡轮蜗杆stress analysis 应力分析 life expect ancy 预计寿命 spur gear 直齿圆柱齿轮crossed helisal gear 交错轴斜齿轮 2、involute tooth from 渐开线齿形 base cirle 基圆 helix angle 螺旋角 thrust load 轴向载荷 radial load 径向载荷3、rigid couplings 刚性连轴器 flexible coupling 柔性联轴器 wear resistance 耐磨性 sealing element密封圈 4、dee