汽車檢測設備中常用傳感器的工作原理及應用

　1、電(dian)(dian)(dian)(dian)(dian)阻(zu)應(ying)(ying)變式(shi)傳感器，主要由(you)電(dian)(dian)(dian)(dian)(dian)阻(zu)應(ying)(ying)變片及(ji)測(ce)量(liang)轉換電(dian)(dian)(dian)(dian)(dian)路等組成；它(ta)是用直徑約0、025mm左右具有(you)高阻(zu)率的(de)(de)電(dian)(dian)(dian)(dian)(dian)阻(zu)絲制成，其規格(ge)一般從有(you)效使用面積及(ji)電(dian)(dian)(dian)(dian)(dian)阻(zu)值(zhi)來(lai)表示；工作原理是將電(dian)(dian)(dian)(dian)(dian)阻(zu)絲應(ying)(ying)變片粘貼在承受外力(li)的(de)(de)零(ling)件(jian)(jian)之(zhi)(zhi)上(shang)，當零(ling)件(jian)(jian)受力(li)變形(xing)時，應(ying)(ying)變片內電(dian)(dian)(dian)(dian)(dian)阻(zu)絲也隨(sui)之(zhi)(zhi)變形(xing)，從而(er)使電(dian)(dian)(dian)(dian)(dian)阻(zu)值(zhi)發生變化；通過測(ce)量(liang)轉換電(dian)(dian)(dian)(dian)(dian)路將電(dian)(dian)(dian)(dian)(dian)阻(zu)的(de)(de)變化轉換成電(dian)(dian)(dian)(dian)(dian)壓或電(dian)(dian)(dian)(dian)(dian)流的(de)(de)變化達到測(ce)量(liang)零(ling)件(jian)(jian)變形(xing)、受力(li)等目的(de)(de)；應(ying)(ying)用：測(ce)量(liang)加速度、測(ce)力(li)和(he)稱重；
　　2、熱(re)電(dian)(dian)(dian)(dian)(dian)阻(zu)傳感器，主要用于測(ce)量溫度和與溫度有(you)關(guan)的(de)(de)參(can)量，按(an)熱(re)電(dian)(dian)(dian)(dian)(dian)阻(zu)性(xing)質(zhi)不同可分為金(jin)(jin)屬(shu)(shu)熱(re)電(dian)(dian)(dian)(dian)(dian)阻(zu)和半導體熱(re)電(dian)(dian)(dian)(dian)(dian)阻(zu)兩類；通(tong)常前者(zhe)稱熱(re)電(dian)(dian)(dian)(dian)(dian)阻(zu)，后者(zhe)稱為熱(re)敏(min)電(dian)(dian)(dian)(dian)(dian)阻(zu)；工作原(yuan)理(li)：熱(re)敏(min)電(dian)(dian)(dian)(dian)(dian)阻(zu)主要是利用電(dian)(dian)(dian)(dian)(dian)阻(zu)隨(sui)溫度升(sheng)高(gao)而增加(jia)這(zhe)一特性(xing)來測(ce)量溫度的(de)(de)，溫度升(sheng)高(gao)，金(jin)(jin)屬(shu)(shu)內部(bu)的(de)(de)自由電(dian)(dian)(dian)(dian)(dian)子通(tong)過(guo)金(jin)(jin)屬(shu)(shu)導體時的(de)(de)阻(zu)力增加(jia)，宏觀上(shang)表(biao)現出電(dian)(dian)(dian)(dian)(dian)阻(zu)率變大，總電(dian)(dian)(dian)(dian)(dian)阻(zu)值增加(jia)；
　　3、電(dian)(dian)(dian)(dian)感(gan)(gan)式(shi)(shi)傳(chuan)感(gan)(gan)器(qi)，1〕自感(gan)(gan)式(shi)(shi)電(dian)(dian)(dian)(dian)感(gan)(gan)傳(chuan)感(gan)(gan)器(qi)主要有(you)線圈(quan)(quan)、鐵心、銜(xian)鐵及測(ce)(ce)桿等組(zu)成；工(gong)作時(shi)，銜(xian)鐵通過測(ce)(ce)桿與(yu)被(bei)測(ce)(ce)物(wu)體相(xiang)接觸，被(bei)測(ce)(ce)物(wu)體的(de)(de)位移(yi)將(jiang)引起線圈(quan)(quan)電(dian)(dian)(dian)(dian)感(gan)(gan)量(liang)(liang)(liang)(liang)的(de)(de)變(bian)(bian)化(hua)，當傳(chuan)感(gan)(gan)器(qi)線圈(quan)(quan)接入測(ce)(ce)量(liang)(liang)(liang)(liang)轉換電(dian)(dian)(dian)(dian)路(lu)后電(dian)(dian)(dian)(dian)感(gan)(gan)的(de)(de)變(bian)(bian)化(hua)將(jiang)被(bei)轉換為(wei)電(dian)(dian)(dian)(dian)壓(ya)(ya)，電(dian)(dian)(dian)(dian)流或頻率的(de)(de)變(bian)(bian)化(hua)，從而完成非電(dian)(dian)(dian)(dian)量(liang)(liang)(liang)(liang)到到電(dian)(dian)(dian)(dian)量(liang)(liang)(liang)(liang)的(de)(de)轉換；2）互感(gan)(gan)式(shi)(shi)電(dian)(dian)(dian)(dian)傳(chuan)感(gan)(gan)器(qi)，是由(you)兩個完全相(xiang)同的(de)(de)單個線圈(quan)(quan)的(de)(de)電(dian)(dian)(dian)(dian)感(gan)(gan)傳(chuan)感(gan)(gan)器(qi)并用(yong)一(yi)根(gen)活動(dong)銜(xian)鐵組(zu)成；當銜(xian)鐵隨被(bei)測(ce)(ce)量(liang)(liang)(liang)(liang)移(yi)動(dong)而偏離(li)中(zhong)間位置時(shi)，兩個線圈(quan)(quan)中(zhong)電(dian)(dian)(dian)(dian)壓(ya)(ya)或電(dian)(dian)(dian)(dian)流變(bian)(bian)化(hua)的(de)(de)餓差值，即可測(ce)(ce)的(de)(de)位移(yi)量(liang)(liang)(liang)(liang)的(de)(de)變(bian)(bian)化(hua)；應用(yong)：測(ce)(ce)量(liang)(liang)(liang)(liang)位移(yi)、測(ce)(ce)量(liang)(liang)(liang)(liang)壓(ya)(ya)力、測(ce)(ce)量(liang)(liang)(liang)(liang)轉速；
　　4、壓(ya)電式(shi)傳感(gan)器(qi)，是一種自發電式(shi)傳感(gan)器(qi)，它以(yi)某些電介質(zhi)的(de)(de)壓(ya)電效(xiao)應為(wei)基礎(chu)，在外(wai)力作用下，電介質(zhi)表面產生電荷，從而使(shi)非(fei)電量(liang)轉化為(wei)電量(liang)進行(xing)測量(liang)；工(gong)作原(yuan)理及(ji)(ji)應用：采用壓(ya)電式(shi)傳感(gan)器(qi)制造的(de)(de)發動(dong)機爆(bao)(bao)震傳感(gan)器(qi)，發動(dong)機內(nei)產生的(de)(de)爆(bao)(bao)震通(tong)過(guo)汽缸壁(bi)傳遞至殼體，通(tong)過(guo)基板(ban)再到(dao)振動(dong)板(ban)上，將變形加(jia)到(dao)壓(ya)電元(yuan)(yuan)件上，使(shi)壓(ya)電元(yuan)(yuan)件出現拉伸及(ji)(ji)壓(ya)縮，由此爆(bao)(bao)震時(shi)產生的(de)(de)特征(zheng)頻率變換為(wei)電信號經接線柱輸送出來；
　　5、超聲(sheng)(sheng)波(bo)傳感器，在汽車及檢測設(she)備中常用于測量(liang)流量(liang)，厚度及工(gong)件內部隱傷等，超聲(sheng)(sheng)波(bo)由超聲(sheng)(sheng)波(bo)換能器〔或稱為(wei)超聲(sheng)(sheng)波(bo)探(tan)(tan)頭〕產(chan)生和(he)接收，主(zhu)要(yao)有(you)以固體為(wei)傳導介(jie)質(zhi)的(de)探(tan)(tan)頭和(he)以空氣為(wei)傳導介(jie)質(zhi)的(de)探(tan)(tan)頭；
　　6、霍爾傳(chuan)感(gan)器，是將金(jin)屬或(huo)(huo)半導體薄片垂(chui)直放(fang)置(zhi)于磁(ci)感(gan)應強度磁(ci)場中，此時(shi)若(ruo)有(you)電(dian)流流過金(jin)屬或(huo)(huo)半導體薄片，在垂(chui)直于電(dian)流和(he)磁(ci)場的(de)方向上將產生電(dian)動勢，利用(yong)(yong)這一(yi)原理制作而(er)成(cheng)的(de)傳(chuan)感(gan)稱(cheng)為霍爾傳(chuan)感(gan)器；應用(yong)(yong)：量(liang)轉速檢測、發動機曲軸位置(zhi)；
　　7、光(guang)電(dian)傳感(gan)器(qi)；是(shi)將光(guang)信(xin)(xin)號(hao)轉換為電(dian)信(xin)(xin)號(hao)的一種(zhong)傳感(gan)器(qi)，使用(yong)這種(zhong)傳感(gan)器(qi)測(ce)(ce)量其它非電(dian)量時(shi)，只(zhi)要將這些非電(dian)量轉換為光(guang)信(xin)(xin)號(hao)的變化即可，此種(zhong)測(ce)(ce)量方法(fa)具有結構簡單(dan)、精(jing)度高(gao)、反應(ying)快(kuai)等優點，廣(guang)泛應(ying)用(yong)于汽車(che)及汽車(che)檢(jian)測(ce)(ce)技術中；應(ying)用(yong)：測(ce)(ce)量液體濁度、測(ce)(ce)量轉速。