1、.位移傳感器又稱為線性傳感器，它分為電感式位移傳感器，電容式位移傳感器，光電式位移傳感器，位移傳感器超聲波式位移傳感器，霍爾式位移傳感器。 電感式位移傳感器是一種屬于金屬感應的線性器件，接通電源后，在開關的感應面將產生一個交變磁場，當金屬物體接近此感應面時，金屬中則產生渦流而吸取了振蕩器的能量，使振蕩器輸出幅度線性衰減，然后根據衰減量的變化來完成無接觸檢測物體的目的。簡介 電感式位移傳感器具有無滑動觸點，工作時不受灰塵等非金屬因素的影響，并且低功耗，長壽命，可使用在各種惡劣條件下。位移傳感器主要應用在自動化裝備生產線對模擬量的智能控制。 位移是和物體的位置在運動過程中的移動有關的量，位移的測量

2、方式所涉及的范圍是相當廣泛的。小位移通常用應變式、電感式、差動變壓器式、渦流式、霍爾傳感器來檢測，大的位移常用感應同步器、光柵、容柵、磁柵等傳感技術來測量。其中光柵傳感器因具有易實現數字化、精度高（目前分辨率最高的可達到納米級）、抗干擾能力強、沒有人為讀數誤差、安裝方便、使用可靠等優點，在機床加工、檢測儀表等行業中得到日益廣泛的應用。原理 計量光柵是利用光柵的莫爾條紋現象來測量位移的。“莫爾”原出于法文Moire，意思是水波紋。幾百年前法國絲綢工人發現，當兩層薄絲綢疊在一起時，將產生水波紋狀花樣；如果薄綢子相對運動，則花樣也跟著移動，這種奇怪的花紋就是莫爾條紋。一般來說，只要是有一定周期的曲線

3、簇重疊起來，便會產生莫爾條紋。計量光柵在實際應用上有透射光柵和反射光柵兩種；按其作用原理又可分為輻射光柵和相位光柵；按其用途可分為直線光柵和圓光柵。下面以透射光柵為例加以討論。透射光柵尺上均勻地刻有平行的刻線即柵線，a為刻線寬，b為兩刻線之間縫寬，W=a+b稱為光柵柵距。目前國內常用的光柵每毫米刻成10、25、50、100、250條等線條。光柵的橫向莫爾條紋測位移，需要兩塊光柵。一塊光柵稱為主光柵，它的大小與測量范圍相一致；另一塊是很小的一塊，稱為指示光柵。為了測量位移，必須在主光柵側加光源，在指示光柵側加光電接收元件。當主光柵和指示光柵相對移動時，由于光柵的遮光作用而使莫爾條紋移動，固定在指

4、示光柵側的光電元件，將光強變化轉換成電信號。由于光源的大小有限及光柵的衍射作用，使得信號為脈動信號。信號處理辨向原理 在實際應用中，位移具有兩個方向，即選定一個方向后，位移有正負之分，因此用一個光電元件測定莫爾條紋信號確定不了位移方向。為了辨向，需要有 /2相位差的兩個莫爾條紋信號。 細分技術 隨著對測量精度要求的提高，以柵距為單位已不能滿足要求，需要采取適當的措施對莫爾條紋進行細分。所謂細分就是在莫爾條紋信號變化一個周期內，發出若干個脈沖，以減少脈沖當量。如一個周期內發出n個脈沖，則可使測量精度提高n備，而每個脈沖相當于原來柵距的1/n。由于細分后計數脈沖頻率提高了 n倍，因此也稱n倍頻。通

5、常用的有兩種細分方法：其一、直接細分。在相差1/4莫爾條紋間距的位置上安放兩個光電元件，可得到兩個相位差90°的電信號，用反相器反相后就得到四個依次相差90°的交流信號。同樣，在兩莫爾條紋間放置四個依次相距1/4條紋間距的光電元件，也可獲得四個相位差90°的交流信號，實現四倍頻細分。其二、電路細分。專用集成電路 四倍頻專用集成電路QA740210同時具有辨相和四倍頻細分的功能，可將兩路正交的方波進行四倍頻后產生兩路加、減計數信號，可送雙時鐘可逆計數器進行加、減計數，也可直接送微型計算機（包括單片機）進行數據處理。 1、特點： 、數字化微分電路：4路微分信號脈寬由主

6、頻周期決定，因此，是一致的，而且可在很大范圍里方便地選擇。 、臨界報警與過速報警兩檔速度提示：可在光柵運動速度接近極限值時給出臨界報警信息，以便操作者及時控制光柵運動快慢。在速度超過極限值時本電路將給出出錯信息。 、絕對零位控制：絕對零位的設置將給操作者帶來許多方便，如故障斷電后的重新定位等。本電路有“到絕對零位開始計數”和“到絕對零位停止計數”，以及“與絕對零位無關”三種工作模式。 、片選：本電路設有片選端，可以構成多標數顯系統。 、COMS工藝：輸入輸出的電壓電流與4000系列CMOS及LSTTL電路兼容。分類根據運動方式分類直線位移傳感器原理： 直線位移傳感器的功能在于把直線機械位移量轉

7、換成電信號。為了達到這一效果，通常將可變電阻滑軌定置在傳感器的固定部位，通過滑片在滑軌上的位移來測量不同的阻值。傳感器滑軌連接穩態直流電壓，允許流過微安培的小電流，滑片和始端之間的電壓，與滑片移動的長度成正比。將傳感器用作分壓器可最大限度降低對滑軌總阻值精確性的要求，因為由溫度變化引起的阻值變化不會影響到測量結果。 LT直線位移傳感器： 廣泛應用于注塑、機床及機械加工等行業 無限分辨率 行程：50至900mm 獨立線性度：±0.05% 位移速度達到：5m/s、10 m/s可選 工作溫度：-30至+100 多種電氣連接方式 保護等級：IP60（IP65可選） 角度位移傳感器根據材質分類

8、金屬膜傳感器、導電塑料傳感器、光電式傳感器、磁敏式傳感器、金屬玻璃鈾傳感器、繞線傳感器。 電位器式位移傳感器 它通過電位器元件將機械位移轉換成與之成線性或任意函數關系的電阻或電壓輸出。普通直線電位器和圓形電位器都可分別用作直線位移和角位移傳感器。但是，為實現測量位移目的而設計的電位器，要求在位移變化和電阻變化之間有一個確定關系。電位器式位移傳感器的可動電刷與被測物體相連。物體的位移引起電位器移動端的電阻變化。阻值的變化量反映了位移的量值，阻值的增加還是減小則表明了位移的方向。通常在電位器上通以電源電壓，以把電阻變化轉換為電壓輸出。線繞式電位器由于其電刷移動時電阻以匝電阻為階梯而變化，其輸出特性

9、亦呈階梯形。如果這種位移傳感器在伺服系統中用作位移反饋元件，則過大的階躍電壓會引起系統振蕩。因此在電位器的制作中應盡量減小每匝的電阻值。電位器式傳感器的另一個主要缺點是易磨損。它的優點是：結構簡單，輸出信號大，使用方便，價格低廉。 霍耳式位移傳感器 它的測量原理是保持霍耳元件（見半導體磁敏元件）的激勵電流不變，并使其在一個梯度均勻的磁場中移動，則所移動的位移正比于輸出的霍耳電勢。磁場梯度越大，靈敏度越高；梯度變化越均勻,霍耳電勢與位移的關系越接近于線性。霍耳式位移傳感器的慣性小、頻響高、工作可靠、壽命長，因此常用于將各種非電量轉換成位移后再進行測量的場合。 光電式位移傳感器 它根據被測對象阻擋

10、光通量的多少來測量對象的位移或幾何尺寸。特點是屬于非接觸式測量，并可進行連續測量。光電式位移傳感器常用于連續測量線材直徑或在帶材邊緣位置控制系統中用作邊緣位置傳感器。傳感器市場發展前景咨詢公司INTECHNOCONSULTING的傳感器市場報告顯示，2008年全球傳感器市場容量為506億美元，預計2010年全球傳感器市場可達600億美元以上。調查顯示，東歐、亞太區和加拿大成為傳感器市場增長最快的地區，而美國、德國、日本依舊是傳感器市場分布最大的地區。就世界范圍而言，傳感器市場上增長最快的依舊是汽車市場，占第二位的是過程控制市場，看好通訊市場前景。目前，全球的傳感器市場在不斷變化的創新之中呈現出

11、快速增長的趨勢。有關專家指出，傳感器領域的主要技術將在現有基礎上予以延伸和提高，各國將競相加速新一代傳感器的開發和產業化，競爭也將日益激烈。新技術的發展將重新定義未來的傳感器市場，比如無線傳感器、光纖傳感器、智能傳感器和金屬氧化傳感器等新型傳感器的出現與市場份額的擴大。Linear displacement transducer, also known as the sensor, which is divided into inductive displacement sensor, capacitive displacement sensors, optical displacement

12、sensor, displacement sensor ultrasonic displacement sensors, Hall-type displacement sensor. Inductive displacement sensor is a metal sensor is a linear device, powered on, the switch sensor surface will result in an alternating magnetic field, when the metal object close to the sensor surface, the m

13、etal in the vortex and absorb the energy of the oscillator, the oscillator output amplitude of linear attenuation, attenuation changes and then to complete the purpose of non-contact detection of objects.IntroductionInductive displacement sensor with no moving contacts from dust and other non-metall

14、ic work factors, and low power consumption, long life, can be used in a variety of harsh conditions. Displacement sensors are used in automated production line equipment, analog intelligent control.Displacement and position of objects in motion on the amount of movement and displacement of the scope

15、 of measurement is quite extensive. Usually small displacement strain, inductive, differential transformer, eddy current, Hall sensors to detect the displacement of a large common inductosyn, grating, capacitive, magnetic and other sensor technology to measure the gate. Grating sensors which are eas

16、y to achieve because of digital, high accuracy (currently the highest resolution up to nano-scale), anti-interference ability, no one reading error, easy to install, use and reliable, in machining, instrumentation and other industries Been increasingly widely used.PrincipleMetrological grating is th

17、e use of grating moire fringe phenomenon to measure the displacement. "Moore" For the original French Moire, which means the water ripple. French silk workers found when the two layers of thin silk, stacked together, will have a ripple-like pattern hundreds of years ago; if the relative mo

18、tion of thin silk, the pattern will move with it, this strange is the moire fringe pattern. Generally, as long as there is a certain cycle curve clusters overlap, they will produce Moire fringe. Grating in the practical application of measurement has two transmission gratings and reflection gratings

19、; action principle can be classified according to their radiation grating and phase grating; according to their use can be divided into linear and circular gratings. The following example to be discussed transmission grating. Transmission grating engraved on a uniform that is parallel to the gate li

20、ne engraved line, a line width for the moment, b is fracture width between the two groove, W = a + b as grating pitch. Currently used carved 10,25,50,100,250 per mm grating strips lines. Moire fringe grating measured horizontal displacement, need two gratings. A grating as the main grating, its size

21、 is consistent with the measurement range; the other one is a very small, as instructed grating. To measure the displacement must be added in the main grating side of the light source, grating side of the instruction plus photoelectric receiving elements. When the primary grating and grating relativ

22、e movement direction, the shading effect of leaving the grating Moiré fringe mobile, fixed grating in the direction side of the optical components, the light intensity changes into electrical signals. Since the limited size of the light source and diffraction grating effect, making the signal f

23、or the pulse signal.Signal ProcessingTo the principles identifiedIn practice, the displacement has two directions, that is, choose a direction, the displacement of the positive and negative points, so with a determination of Moire fringe optoelectronic devices can not determine the direction of disp

24、lacement. In order to distinguish the need to have / 2 phase difference of the two moiré fringe signals.SubdivisionWith the improvement of measurement accuracy, to pitch as a unit can not meet the requirements, the need to take appropriate measures to be broken down on the Moire fringe. Subdivi

25、sion is the so-called changes in the moiré fringe of a cycle, issued a number of pulses to reduce the pulse equivalent. If given within a period of n pulses, the accuracy can improve n equipment, and each pulse is equivalent to the original pitch of 1 / n. After the count of the sub-pulse frequ

26、ency increased n times, so also called n multiplier. There are two commonly used subdivision method: First, the direct segment. The difference between the 1 / 4 position on the Moire fringe spacing placed the two optical components, get the two 90 ° phase difference signal, the use of four inve

27、rter followed by a difference of RP after 90 ° of the AC signal. Similarly, in the two moire fringe order of distance between the place four 1 / 4 fringe spacing of the optoelectronic components, are available to the exchange of the four 90 ° phase difference signal, to achieve four interp

28、olated. Second, the circuit is broken down.ASIC朗讀ASIC QA740210 quadrature phase and also has identified four segments of the function of frequency can be two orthogonal frequency square wave generated after four two-Luke, by counting the signal, can send even the clock reversible counter Add, subtra

29、ct, count, can also be sent directly to micro-computer (including MCU) for data processing.1, features:顯示對應的拉丁字符的拼音朗讀顯示對應的拉丁字符的拼音, digital differential circuit: 4 Differential pulse width determined by the frequency of cycles, therefore, is consistent, and can be easily in a wide range of choices.,

30、criticality alarm and over-speed warning two speed Tip: You can limit the grating velocity when approaching the critical alarm information is given to the operator speed control in a timely grating movement. Faster than the time limit in the circuit will give an error message., absolutely zero contr

31、ol: absolute zero setting will bring much convenience operators, such as power failure after the re-positioning. This circuit has "absolutely zero to start counting"and"stop the count to the absolute zero"and"has nothing to do with the absolute zero" three modes., Chip

32、Select: This circuit has a chip select terminal, it can be multi-standard digital display system., COMS process: input and output voltage and current with the 4000 series CMOS and LSTTL circuits compatible.CategoriesClassified according to the motion methodLinear displacement sensorPrinciple:Functio

33、n of linear displacement sensor is the linear mechanical displacement into electrical signals. To this effect, usually slide-set variable resistor the fixed part of the sensor, through the slider on the rail to measure the displacement of different resistance. Steady-state DC voltage rails connectin

34、g the sensor to allow a small flow through the micro-ampere current, slip between the film and the beginning of the voltage terminal, and the length of vane movement. The sensor can be used as a divider rails to minimize the total resistance of the requirements of accuracy, because the resistance ca

35、used by the change of temperature change will not affect the measurement results.LT linear displacement sensor: widely used in injection molding, machine tool and machining industry infinite resolution Duration: 50 to 900mm Independent Linearity: ± 0.05% displacement speed: 5m / s, 10 m / s opt

36、ional Operating temperature: -30 to +100 a variety of electrical connections Protection class: IP60 (IP65 optional)Angular displacement sensorAccording to classified materialMetal film sensors, conductive plastic sensors, photoelectric sensors, magnetic sensors, metal glass uranium sensor, the senso

37、r winding.Potentiometer displacement sensors which components will be through the potentiometer associated mechanical displacement into a linear or any function of the resistance or voltage output. General linear and circular potentiometer potentiometer can be used as a linear displacement, respecti

38、vely, and the angular displacement sensor. However, to achieve the purpose of measuring the displacement potentiometer designed to require change and resistance change in the displacement of a definite relationship between. Potentiometer displacement sensors and the measured object can be linked to

39、dynamic brush. Potentiometer caused the displacement of objects moving side of the resistance change. Reflect the change in resistance value of displacement, the increase or decrease the resistance that the displacement direction. Usually pass on the potentiometer to supply voltage to the resistance

40、 change is converted to voltage output. Wirewound potentiometer wiper is moved due to its resistance to change turn resistance ladder, the ladder-shaped output characteristic was also found .If this displacement sensor used in the servo system position feedback device, the excessive voltage can caus

41、e system oscillation step. Therefore, the production of the potentiometer should be to minimize the resistance of each turn. Potentiometer sensor is another major drawback is easy to wear. Its advantages are: simple structure, large output, convenient, low prices.Hall displacement sensor measuring p

42、rinciple is to maintain its Hall component (see semiconductor magnetic components) of the excitation current constant, and make it in a uniform magnetic field gradient to move, then move the displacement is proportional to the output of the Hall Potential. The greater the magnetic field gradient, th

43、e higher the sensitivity; gradient more uniform, Hall electric potential and the closer relationship between the linear displacement. Hall of inertia displacement sensors, high frequency response, reliable, long life, so commonly used in all kinds of non-electricity and then converted into the displacement measurement occasions.Optical displacement sensor is based on the number of the measured object to block the flux measurement object displacement or geometry. Cha