電磁鐵的發明

1822年，法國物理學家阿拉戈和呂薩克發現，當電流通過其中有鐵塊的繞線時，它能使繞線中的鐵塊磁化。這實際上是昆明電磁鐵原理的(de)(de)(de)最初發現。1823年，斯特金也做了(le)一(yi)次類似的(de)(de)(de)實驗：他在(zai)一(yi)根并非是磁(ci)鐵(tie)(tie)(tie)棒(bang)的(de)(de)(de)U型(xing)鐵(tie)(tie)(tie)棒(bang)上繞(rao)了(le)18圈(quan)銅(tong)裸線(xian)，當銅(tong)線(xian)與伏(fu)打電(dian)池接通時(shi)，繞(rao)在(zai)U型(xing)鐵(tie)(tie)(tie)棒(bang)上的(de)(de)(de)銅(tong)線(xian)圈(quan)即產生了(le)密集的(de)(de)(de)磁(ci)場，這(zhe)樣就使U型(xing)鐵(tie)(tie)(tie)棒(bang)變成了(le)一(yi)塊“電(dian)磁(ci)鐵(tie)(tie)(tie)”。這(zhe)種電(dian)磁(ci)鐵(tie)(tie)(tie)上的(de)(de)(de)磁(ci)能要比(bi)永磁(ci)能大放多倍，它能吸(xi)起比(bi)它重(zhong)20倍的(de)(de)(de)鐵(tie)(tie)(tie)塊，而(er)當電(dian)源切斷后，U型(xing)鐵(tie)(tie)(tie)棒(bang)就什么鐵(tie)(tie)(tie)塊也吸(xi)不住(zhu)，重(zhong)新成為一(yi)根普通的(de)(de)(de)鐵(tie)(tie)(tie)棒(bang)。

斯特金的(de)(de)電磁鐵發明(ming)(ming)，使人們看(kan)到了(le)把電能轉(zhuan)化為磁能的(de)(de)光明(ming)(ming)前景，這(zhe)一(yi)發明(ming)(ming)很快在(zai)英國(guo)、美(mei)國(guo)以及西歐一(yi)些(xie)沿海(hai)國(guo)家傳播開來。

1829年(nian)，美國電(dian)學家亨(heng)利對(dui)斯特金電(dian)磁鐵裝置(zhi)進行了(le)一(yi)些革新，絕緣導(dao)(dao)線(xian)(xian)代替裸銅(tong)導(dao)(dao)線(xian)(xian)，因此不(bu)必(bi)擔心被銅(tong)導(dao)(dao)線(xian)(xian)過分靠(kao)近而(er)短路(lu)。由于(yu)導(dao)(dao)線(xian)(xian)有(you)了(le)絕緣層，就(jiu)(jiu)可以(yi)將它(ta)們一(yi)圈(quan)圈(quan)地緊緊地繞在一(yi)起，由于(yu)線(xian)(xian)圈(quan)越(yue)密(mi)集，產(chan)生的(de)(de)(de)磁場就(jiu)(jiu)越(yue)強(qiang)，這樣就(jiu)(jiu)大大提高了(le)把電(dian)能轉(zhuan)化為磁能的(de)(de)(de)能力(li)。到(dao)了(le)1831年(nian)，亨(heng)利試制(zhi)出了(le)一(yi)塊更新的(de)(de)(de)電(dian)磁鐵，雖然它(ta)的(de)(de)(de)體積并不(bu)大，但它(ta)能吸起1噸重的(de)(de)(de)鐵塊。

電(dian)(dian)(dian)磁(ci)鐵(tie)(tie)內部帶(dai)有(you)鐵(tie)(tie)心的(de)(de)、利用(yong)(yong)通(tong)有(you)電(dian)(dian)(dian)流(liu)的(de)(de)線圈使其像磁(ci)鐵(tie)(tie)一樣具有(you)磁(ci)性(xing)的(de)(de)裝置叫做(zuo)電(dian)(dian)(dian)磁(ci)鐵(tie)(tie)，通(tong)常制(zhi)(zhi)成(cheng)條形或蹄(ti)形。鐵(tie)(tie)心要(yao)用(yong)(yong)容(rong)易(yi)磁(ci)化，又容(rong)易(yi)消失(shi)磁(ci)性(xing)的(de)(de)軟鐵(tie)(tie)或硅鋼來制(zhi)(zhi)做(zuo)。這樣的(de)(de)電(dian)(dian)(dian)磁(ci)鐵(tie)(tie)在(zai)通(tong)電(dian)(dian)(dian)時有(you)磁(ci)性(xing)，斷電(dian)(dian)(dian)后(hou)就隨(sui)之消失(shi)。 電(dian)(dian)(dian)磁(ci)鐵(tie)(tie)有(you)許多(duo)優點：電(dian)(dian)(dian)磁(ci)鐵(tie)(tie)磁(ci)性(xing)的(de)(de)有(you)無，可以(yi)用(yong)(yong)通(tong)、斷電(dian)(dian)(dian)流(liu)控制(zhi)(zhi)。磁(ci)性(xing)的(de)(de)大小(xiao)可以(yi)用(yong)(yong)電(dian)(dian)(dian)流(liu)的(de)(de)強弱或線圈的(de)(de)匝數來控制(zhi)(zhi)。

電磁鐵的主要特點

1、采(cai)用全密封結構(gou)，防潮性(xing)能好。

2、經計(ji)(ji)算機優化設(she)計(ji)(ji)，結構合理、自(zi)重輕(qing)、吸(xi)力(li)大(da)、能耗低。

3、勵磁線圈經特別工藝處(chu)理，提(ti)高了線圈的電器和機械性能，絕緣資料熱等級到(dao)達C級，運用壽命長。

4、普通(tong)型(xing)電(dian)磁鐵的額(e)定通(tong)電(dian)持續率由曩昔的50%提高到60%，提高了電(dian)磁鐵的運用功率。

5、超(chao)高溫(wen)型電(dian)磁(ci)鐵采用獨特(te)隔熱(re)方式，其間被吸(xi)物溫(wen)度有曩昔的600℃提高700℃，擴大了電(dian)磁(ci)鐵的適用范圍。

6、裝置(zhi)、運轉、保護(hu)簡潔(jie)。

電磁鐵工作原理

將(jiang)電(dian)(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)能(neng)(neng)(neng)變換為機械(xie)能(neng)(neng)(neng)以實現吸(xi)(xi)合作功的(de)一種電(dian)(dian)(dian)(dian)(dian)器(qi)。通(tong)常由軟磁(ci)(ci)(ci)(ci)材料(liao)(liao)制成(cheng)的(de)鐵(tie)(tie)(tie)心(xin)、銜鐵(tie)(tie)(tie)和(he)勵磁(ci)(ci)(ci)(ci)繞組組成(cheng)。當勵磁(ci)(ci)(ci)(ci)繞組通(tong)電(dian)(dian)(dian)(dian)(dian)時，繞組周圍產(chan)生(sheng)磁(ci)(ci)(ci)(ci)場，鐵(tie)(tie)(tie)心(xin)磁(ci)(ci)(ci)(ci)化，并產(chan)生(sheng)電(dian)(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)吸(xi)(xi)力吸(xi)(xi)引(yin)銜鐵(tie)(tie)(tie)，使之運(yun)動(dong)作功。電(dian)(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)鐵(tie)(tie)(tie)主要用(yong)(yong)于(yu)操動(dong)、牽引(yin)機械(xie)裝(zhuang)置，以達到預(yu)期的(de)目的(de)。工(gong)業上常用(yong)(yong)的(de)電(dian)(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)鐵(tie)(tie)(tie)有(you)(you)制動(dong)電(dian)(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)鐵(tie)(tie)(tie)、牽引(yin)電(dian)(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)鐵(tie)(tie)(tie)、起重電(dian)(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)鐵(tie)(tie)(tie)和(he)閥(fa)用(yong)(yong)電(dian)(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)鐵(tie)(tie)(tie)等。此外，屬(shu)于(yu)電(dian)(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)鐵(tie)(tie)(tie)類的(de)還有(you)(you)用(yong)(yong)以傳遞或(huo)隔斷兩(liang)軸間(jian)的(de)機械(xie)聯系的(de)電(dian)(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)聯軸器(qi);用(yong)(yong)在機床(chuang)工(gong)作臺(tai)上以吸(xi)(xi)牢(lao)磁(ci)(ci)(ci)(ci)性材料(liao)(liao)工(gong)件的(de)電(dian)(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)吸(xi)(xi)盤;供高能(neng)(neng)(neng)物理、核聚變研究、磁(ci)(ci)(ci)(ci)流體(ti)發電(dian)(dian)(dian)(dian)(dian)和(he)高速懸(xuan)浮列車(che)等方(fang)面使用(yong)(yong)的(de)、能(neng)(neng)(neng)產(chan)生(sheng)高達數十特（斯拉）的(de)磁(ci)(ci)(ci)(ci)通(tong)密(mi)度而幾(ji)乎不消耗(hao)繞組功率的(de)超導電(dian)(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)鐵(tie)(tie)(tie)等。

起重電磁鐵

用(yong)來吊(diao)運(yun)(yun)和裝卸鐵(tie)(tie)磁(ci)(ci)性(xing)物體的電磁(ci)(ci)鐵(tie)(tie)。工業上常用(yong)以吊(diao)運(yun)(yun)或(huo)裝卸鐵(tie)(tie)礦石、鐵(tie)(tie)砂、廢鋼(gang)鐵(tie)(tie)、鋼(gang)錠、鋼(gang)軌以及各種鋼(gang)材(cai)和鋼(gang)質工件。起重電磁(ci)(ci)鐵(tie)(tie)通常做(zuo)成圓盤形或(huo)矩(ju)形，并帶有內磁(ci)(ci)極和外磁(ci)(ci)極。當勵磁(ci)(ci)繞(rao)組通電后，內外磁(ci)(ci)極均被磁(ci)(ci)化，吸引鋼(gang)質材(cai)料(liao)或(huo)工件（相當于一般電磁(ci)(ci)鐵(tie)(tie)中的銜鐵(tie)(tie)），形成一個(ge)閉合的磁(ci)(ci)路。為保護勵磁(ci)(ci)繞(rao)組，使之不因磁(ci)(ci)極與被吸引物體間的機械撞擊所損傷，起重電磁(ci)(ci)鐵(tie)(tie)通常采用(yong)甲殼式(shi)結構，并且采用(yong)直流勵磁(ci)(ci)。

牽引電磁鐵

供(gong)牽(qian)(qian)引(yin)和推(tui)斥(chi)機(ji)(ji)械裝(zhuang)置用的(de)(de)一種電(dian)磁(ci)鐵(tie)(tie)。主要(yao)用于各種自動設備中，以(yi)實現遠距(ju)離控制。為了能夠在長行(xing)(xing)程(cheng)下獲得(de)較(jiao)(jiao)大的(de)(de)電(dian)磁(ci)吸(xi)(xi)力(li)，牽(qian)(qian)引(yin)電(dian)磁(ci)鐵(tie)(tie)一般采用吸(xi)(xi)引(yin)特性比較(jiao)(jiao)平(ping)坦的(de)(de)甲殼(ke)式(shi)(shi)結構。其內部裝(zhuang)有(you)鐵(tie)(tie)心(xin)、銜(xian)鐵(tie)(tie)和勵磁(ci)線圈。使用時，將鐵(tie)(tie)心(xin)固定(ding)在機(ji)(ji)械裝(zhuang)置的(de)(de)靜止部件上，銜(xian)鐵(tie)(tie)則連接(jie)在牽(qian)(qian)引(yin)桿上。當勵磁(ci)繞(rao)組通(tong)電(dian)后，鐵(tie)(tie)心(xin)被磁(ci)化，產生電(dian)磁(ci)吸(xi)(xi)力(li)吸(xi)(xi)引(yin)銜(xian)鐵(tie)(tie)，后者則通(tong)過牽(qian)(qian)引(yin)桿來操縱所控制的(de)(de)機(ji)(ji)械裝(zhuang)置的(de)(de)機(ji)(ji)構。為了適應不同控制對象(xiang)的(de)(de)需要(yao)，牽(qian)(qian)引(yin)電(dian)磁(ci)鐵(tie)(tie)有(you)拉動式(shi)(shi)和推(tui)動式(shi)(shi)兩種，但都不具備復位裝(zhuang)置。牽(qian)(qian)引(yin)電(dian)磁(ci)鐵(tie)(tie)的(de)(de)主要(yao)技術指標為一定(ding)行(xing)(xing)程(cheng)下的(de)(de)電(dian)磁(ci)吸(xi)(xi)力(li)、操作(zuo)頻(pin)率和壽命。

制動電磁鐵

作機(ji)械制(zhi)(zhi)(zhi)動(dong)(dong)(dong)用(yong)的(de)一種(zhong)電(dian)磁(ci)(ci)(ci)鐵(tie)(tie)。主(zhu)(zhu)要用(yong)于(yu)電(dian)力(li)驅動(dong)(dong)(dong)裝(zhuang)置和(he)(he)起(qi)重(zhong)運(yun)輸設備(bei)中(zhong)(zhong)，并與(yu)制(zhi)(zhi)(zhi)動(dong)(dong)(dong)器(qi)配(pei)合使(shi)用(yong)，使(shi)電(dian)動(dong)(dong)(dong)機(ji)準(zhun)確(que)停(ting)車和(he)(he)懸(xuan)吊著的(de)重(zhong)物不(bu)致墜落。制(zhi)(zhi)(zhi)動(dong)(dong)(dong)電(dian)磁(ci)(ci)(ci)鐵(tie)(tie)按銜(xian)鐵(tie)(tie)行程(cheng)分為(wei)長行程(cheng)和(he)(he)短(duan)行程(cheng)兩類(lei);按勵(li)磁(ci)(ci)(ci)方(fang)式(shi)分為(wei)直流和(he)(he)交流、并勵(li)和(he)(he)串勵(li)以及(ji)單相(xiang)(xiang)和(he)(he)三相(xiang)(xiang)等種(zhong)類(lei)。制(zhi)(zhi)(zhi)動(dong)(dong)(dong)電(dian)磁(ci)(ci)(ci)鐵(tie)(tie)的(de)工作原理是(shi)：當電(dian)磁(ci)(ci)(ci)鐵(tie)(tie)的(de)繞組通(tong)電(dian)后，銜(xian)鐵(tie)(tie)被(bei)吸(xi)向鐵(tie)(tie)心，并通(tong)過(guo)(guo)制(zhi)(zhi)(zhi)動(dong)(dong)(dong)器(qi)中(zhong)(zhong)的(de)停(ting)檔(dang)壓迫制(zhi)(zhi)(zhi)動(dong)(dong)(dong)桿，使(shi)之(zhi)移動(dong)(dong)(dong)，從而迫使(shi)制(zhi)(zhi)(zhi)動(dong)(dong)(dong)器(qi)松閘。切斷(duan)線圈電(dian)源后，制(zhi)(zhi)(zhi)動(dong)(dong)(dong)桿在彈簧作用(yong)下(xia)使(shi)銜(xian)鐵(tie)(tie)脫離磁(ci)(ci)(ci)軛，而制(zhi)(zhi)(zhi)動(dong)(dong)(dong)器(qi)則(ze)將機(ji)構剎住。制(zhi)(zhi)(zhi)動(dong)(dong)(dong)電(dian)磁(ci)(ci)(ci)鐵(tie)(tie)的(de)主(zhu)(zhu)要技術(shu)參數(shu)是(shi)行程(cheng)、一定(ding)行程(cheng)下(xia)的(de)電(dian)磁(ci)(ci)(ci)吸(xi)力(li)、操作頻率和(he)(he)通(tong)電(dian)持續率。操作頻率是(shi)指每小時(shi)操作的(de)次數(shu);通(tong)電(dian)持續率是(shi)指每次通(tong)電(dian)時(shi)間與(yu)每次通(tong)電(dian)及(ji)不(bu)通(tong)電(dian)時(shi)間之(zhi)和(he)(he)的(de)百分比。使(shi)用(yong)中(zhong)(zhong)，制(zhi)(zhi)(zhi)動(dong)(dong)(dong)電(dian)磁(ci)(ci)(ci)鐵(tie)(tie)與(yu)瓦(wa)式(shi)制(zhi)(zhi)(zhi)動(dong)(dong)(dong)器(qi)相(xiang)(xiang)配(pei)合時(shi)用(yong)短(duan)行程(cheng)類(lei);與(yu)皮帶制(zhi)(zhi)(zhi)動(dong)(dong)(dong)器(qi)相(xiang)(xiang)配(pei)合時(shi)用(yong)長行程(cheng)類(lei)。制(zhi)(zhi)(zhi)動(dong)(dong)(dong)電(dian)磁(ci)(ci)(ci)鐵(tie)(tie)通(tong)過(guo)(guo)液壓方(fang)式(shi)將電(dian)磁(ci)(ci)(ci)力(li)傳(chuan)遞給制(zhi)(zhi)(zhi)動(dong)(dong)(dong)機(ji)構的(de)稱液壓制(zhi)(zhi)(zhi)動(dong)(dong)(dong)電(dian)磁(ci)(ci)(ci)鐵(tie)(tie)。

閥用電磁鐵

供遠(yuan)距離操作(zuo)(zuo)各(ge)種液(ye)壓、氣動系統閥門(men)的(de)電(dian)磁(ci)(ci)(ci)(ci)鐵(tie)(tie)。常用(yong)(yong)于各(ge)種金屬切削機床(chuang)中(zhong)。閥用(yong)(yong)電(dian)磁(ci)(ci)(ci)(ci)鐵(tie)(tie)不設復位裝置，而由閥體(ti)中(zhong)的(de)彈簧使(shi)之(zhi)復位。當(dang)電(dian)磁(ci)(ci)(ci)(ci)鐵(tie)(tie)的(de)勵磁(ci)(ci)(ci)(ci)繞組(zu)通過電(dian)流時，電(dian)磁(ci)(ci)(ci)(ci)吸力(li)(li)(li)即克(ke)服彈簧阻(zu)力(li)(li)(li)，使(shi)閥體(ti)的(de)推(tui)桿移動，將閥門(men)開啟;當(dang)勵磁(ci)(ci)(ci)(ci)繞組(zu)斷(duan)電(dian)后，在復位彈簧作(zuo)(zuo)用(yong)(yong)下，閥體(ti)推(tui)桿便推(tui)動銜鐵(tie)(tie)，使(shi)其移動額定(ding)行程處(chu)，閥門(men)關閉。閥用(yong)(yong)電(dian)磁(ci)(ci)(ci)(ci)鐵(tie)(tie)分(fen)為濕式(shi)和干式(shi)兩種。濕式(shi)閥用(yong)(yong)電(dian)磁(ci)(ci)(ci)(ci)鐵(tie)(tie)的(de)銜鐵(tie)(tie)在液(ye)壓油中(zhong)工作(zuo)(zuo)，由于油的(de)冷(leng)卻(que)作(zuo)(zuo)用(yong)(yong)，使(shi)其與具有相同吸力(li)(li)(li)的(de)電(dian)磁(ci)(ci)(ci)(ci)鐵(tie)(tie)相比，有較小的(de)尺(chi)寸。

電磁鐵的應用

門(men)(men)禁：為什(shen)么門(men)(men)禁可(ke)以(yi)在沒刷卡時把門(men)(men)牢牢的(de)(de)“抓住”？原(yuan)來單元門(men)(men)是(shi)由鋼材料做成的(de)(de)，那(nei)個金(jin)(jin)屬體(ti)(ti)在通(tong)電時可(ke)以(yi)產生強大的(de)(de)磁(ci)場，產生的(de)(de)磁(ci)力能(neng)把門(men)(men)牢牢的(de)(de)吸(xi)住，而刷卡的(de)(de)瞬間，切斷電流，金(jin)(jin)屬體(ti)(ti)失去磁(ci)性，我們就可(ke)以(yi)打開門(men)(men)了。那(nei)個金(jin)(jin)屬體(ti)(ti)其實是(shi)一塊電磁(ci)鐵。

電(dian)磁起重機：最直接的應用(yong)之(zhi)一是(shi)電(dian)磁起重機。電(dian)磁鐵安裝在吊(diao)車上，通電(dian)后吸起大量鋼(gang)鐵，移動到另一個位置后切斷電(dian)流，鋼(gang)鐵被放下，免去了打(da)捆的麻煩。大型電(dian)磁起重機一次可(ke)以吊(diao)起幾噸(dun)鋼(gang)材。

在(zai)電(dian)(dian)(dian)動(dong)機(ji)、發電(dian)(dian)(dian)機(ji)、電(dian)(dian)(dian)鈴和電(dian)(dian)(dian)磁繼電(dian)(dian)(dian)器里也用到電(dian)(dian)(dian)磁鐵。全自動(dong)洗衣機(ji)的(de)進水、排水閥門，衛生間里感(gan)應式沖水器的(de)閥門，也都是由電(dian)(dian)(dian)磁鐵控(kong)制的(de)。

電磁(ci)鐵的另(ling)一個應(ying)用是產生強(qiang)磁(ci)場。現代技術(shu)中很(hen)多(duo)地方(fang)需(xu)要的強(qiang)磁(ci)場都由電磁(ci)鐵提(ti)供，如大型(xing)電動機、發電機、磁(ci)療(liao)設備等。