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单击此处编辑母版标题样式,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,Lesson 7 Basic Knowledge of Transducers and Resistance Transducers,Backgrounds,Text tour,Language in use,Vocabulary,Structure,Reading/writing techniques,11/14/2026,1,测控技术与仪器英语教程,Terminology,Cement,粘接剂,Coefficient,系数,Diaphragm,振动膜,Inductance,电感,Life expectancy,概率寿命,Natural frequency,固有频率,Mutual-inductance,互感,Paper backing,纸其,Resolution,分辩率,Backgrounds,11/14/2026,2,测控技术与仪器英语教程,Text tour,Outline,7.1 Transducer Elements,7.2 Transducer Sensitivity,7.3 Characteristics of an Ideal Transducer,7.4 Electrical Transducers,7.5 Resistance Transducers,11/14/2026,3,测控技术与仪器英语教程,7.1 Transducer Elements,A transducer is a device which converts the quantity being measured into an optical,mechanical,or-more commonly-electrical,Fig7-1 Two-block-diagram representation of a typical,transducer,11/14/2026,4,测控技术与仪器英语教程,7.2 Transducer Sensitivity,transducer sensitivity:the relationship between the,measurand,and the transducer output signal is usually obtained by calibration tests,:,11/14/2026,5,测控技术与仪器英语教程,7.2 Transducer Sensitivity,Example:,Figure 7-2 Loaded spring of example 6.1,11/14/2026,6,测控技术与仪器英语教程,7.3 Characteristics of an Ideal Transducer,characteristics:,)high fidelity-the transducer output waveform shape be a faithful reproduction of the,measurand,;there should be minimum distortion.,)There should be minimum interference with the quantity being measured,)Size.The transducer must be capable of being placed exactly where it is needed.,)There should be a linear relationship between the,measurand,and the transducer signal.,11/14/2026,7,测控技术与仪器英语教程,7.3 Characteristics of an Ideal Transducer,),The transducer should have minimum sensitivity to external effects,pressure transducers,)The natural frequency of the transducer should be well separated from the frequency and harmonics of the,measurand,.,11/14/2026,8,测控技术与仪器英语教程,7.4 Electrical Transducers,Electrical transducers can be divided into two distinct groups:,variable-control-parameter types,:,)resistance;,)capacitance;,)inductance;,)mutual-inductance types.,11/14/2026,9,测控技术与仪器英语教程,7.4 Electrical Transducers,b)self-generating types:,)electromagnetic,)thermoelectric,),photoemissive,),piezo,-electric types.,11/14/2026,10,测控技术与仪器英语教程,7.5 Resistance Transducers,7.5.1,potentiometers,7.5.2 resistance strain gauges,7.5.3 Resistance Temperature Transducers,7.5.4 photoconductive cells,7.5.5,photoemissive,cells,11/14/2026,11,测控技术与仪器英语教程,7.5.1 Potentiometers,construction principles:,Figure 7-3 Construction principles of resistance potentiometers,11/14/2026,12,测控技术与仪器英语教程,7.5.1 Potentiometers,the contact moves from one wire to next(a)and the output voltage of the unload potentiometer circuit(b),(a)(b),Figure 7-4 Resolution effects and circuit diagram of resistance potentiometer,11/14/2026,13,测控技术与仪器英语教程,7.5.1 Potentiometers,the potentiometer causes the output/input graph,Figure 7-5 Characteristic of a loaded potentiometer,11/14/2026,14,测控技术与仪器英语教程,7.5.1 Potentiometers,An analysis of the potentiometer circuit in the loaded condition,11/14/2026,15,测控技术与仪器英语教程,7.5.2 Resistance Strain Gauges,Resistance strain gauges are transducers which exhibit a change in electrical resistance in response to mechanical strain.,a)bonded strain gauges:,)fine wire gauges cemented to paper backing,)photo-etched grids of conducting foil on an epoxy-resin backing,)a single semiconductor filament mounted on an epoxy-resin backing with copper or nickel leads,11/14/2026,16,测控技术与仪器英语教程,7.5.2 Resistance Strain Gauges,unbonded,strain gauges,Figure 7-6,Unbonded,strain gauges,11/14/2026,17,测控技术与仪器英语教程,7.5.3 Resistance Temperature Transducers,Resistance Temperature Transducers can be divided into two main groups:,a)metal resistance temperature transducers,Figure 7-7 Characteristics of a platinum resistance thermometer,11/14/2026,18,测控技术与仪器英语教程,7.5.3 Resistance Temperature Transducers,b),thermistor,(semiconductor)resistance temperature transducers,Figure 7-8 Characteristics of,thermistors,11/14/2026,19,测控技术与仪器英语教程,7.5.4 Photoconductive Cells,The resistance between the metal electrodes decrease as the intensity of the light striking the semiconductor increases.,Figure 7-9 Photoconductive cell,11/14/2026,20,测控技术与仪器英语教程,7.5.5,Photoemissive,Cells,When light strikes the cathode of the,photoemissive,cell,electrons are given sufficient energy to arrive the cathode.,photoemissive,voltage:,Figure 7-11,Photoemissive,cell,11/14/2026,21,测控技术与仪器英语教程,Vocabulary,parameter,classified,external,generate,rotation,Structure,Reading/writing techniques,Language in use,11/14/2026,22,测控技术与仪器英语教程,Vocabulary,11/14/2026,23,测控技术与仪器英语教程,parameter,in dictionary,参数,参量:在相同一般类型的等式中取值变化的等式中的常数或常量,尤其是曲线方程和平面方程中能代表一类曲线或平面的常量,限制因素:限定可能性和结果的因素,决定变数范围的要素,范围,界限:决定变化范围的因素;限度,11/14/2026,24,测控技术与仪器英语教程,parameter,in text,This displacement may then be used to change an electrical,parameter,such as voltage,resistance,capacitance,or inductance.,然后位移可以改变电参数,如电压、电阻、电容或者感应系数。,11/14/2026,25,测控技术与仪器英语教程,Parameter,in use,all the parameters of shelterwhere people will live,what mode of housing they will choose,and how they will pay for it,住宿的所有限制因素,人们住在哪里、他们将选择什么样的住房式样以及他们如何付房钱,an experimental school that keeps expanding the parameters of its curriculum.,一所不断扩展课程范围的实验学校,11/14/2026,26,测控技术与仪器英语教程,classified,in dictionary,分门别类的:划分到阶级或类别中的,机密的,保密的:只提供给获得授权的人的,如因国家安全的原因:,11/14/2026,27,测控技术与仪器英语教程,classified,in text,Transducers are,classified,according to the transduction principle involved and the form of the,measurand,.,按照转换原理和测量形式对传感器进行分类。,11/14/2026,28,测控技术与仪器英语教程,classified,in use,a classified document.,机密文件,11/14/2026,29,测控技术与仪器英语教程,external,in dictionary,外面的,外在的:与外面或外部有关的,出现在外面或外部的,与外面或外部有联系的;外部的,外用的:适于外面使用的:,客观的,物质的:与精神无关的,外界的:存在或来自于外界或外面的:,外表的,外观的:外表的,主要和外表有关的;表面的:,外国的,国际的:外国的事务或外国的,与其有关的:,11/14/2026,30,测控技术与仪器英语教程,external,in text,The transducer should have minimum sensitivity to,external,effects,pressure transducers,for example,are often subjected to external effects such vibration and temperature.,传感器对外部影响的灵敏度应该小,例如压力传感器经常受到外部振动和温度的影响。,11/14/2026,31,测控技术与仪器英语教程,external,in use,external paints.,外用涂料,external pressures.,外界的压力,An internal sense of righteousness dwindles into an external concern for reputation,内心的正义感变成对外在名誉的关心,the countrys minister of external affairs.,该国的外交部长,11/14/2026,32,测控技术与仪器英语教程,generate,in dictionary,形成,造成:,产生物理反应:作为化学或物理变化过程的结果而产生,产生(后代);生育,形成(几何图形):用画曲线或面来作出(一个几何图形),生成,产生:通过命令计算机遵循用于代码段的给定参数来编制一个(程序,),11/14/2026,33,测控技术与仪器英语教程,generate,in text,Electrical noise may be generated by variation in contact resistance,by mechanical wear due to contact friction,and by contact vibration transmitted from the sensing element.,电子噪声可以通过接触电阻的振动、触头摩擦形成的机械磨损以及从敏感元件传出的触头振动产生,.,11/14/2026,34,测控技术与仪器英语教程,generate,in use,generate a discussion.,造成一场争论,generate heat.,产生热,11/14/2026,35,测控技术与仪器英语教程,rotation,in dictionary,旋转,转动:绕中心或轴转动的行为或过程,旋转一圈,旋度:一种坐标系的转变,新的坐标轴从原位置位移的一定角度而原点保持不变,轮换,轮作:在一个次序或序列中定期的变动:,轮番台球:台球游戏中击球的顺序,其中球桌上数码最小的球总是最先被击落袋中,11/14/2026,36,测控技术与仪器英语教程,rotation,in text,The wear on the contacting surface limits the life of a potentiometer to a finite number of full strokes or,rotation,s,usually referred to in the manufacturers specification as the number of cycles of life expectancy,a typical value being cycles.,触头表面的磨损将电位器的寿命限制为多少转。通常指的是生产商在说明书中提及的“寿命转数”,一个典型值为,20106,转。,11/14/2026,37,测控技术与仪器英语教程,rotation,in use,the axial rotation of the earth.,地球绕轴自转,a rotation of personnel;crop rotation.,员工的轮流替换;农作物的轮作,11/14/2026,38,测控技术与仪器英语教程,Structure,11/14/2026,39,测控技术与仪器英语教程,Reading/writing techniques,11/14/2026,40,测控技术与仪器英语教程,
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