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。這實際上是湖北電磁鐵原理(li)的(de)最初發現(xian)。1823年，斯特金也做(zuo)了(le)一(yi)次(ci)類似的(de)實驗：他在一(yi)根(gen)并非是(shi)磁(ci)鐵(tie)(tie)(tie)(tie)棒(bang)(bang)的(de)U型鐵(tie)(tie)(tie)(tie)棒(bang)(bang)上(shang)繞(rao)了(le)18圈(quan)銅裸線(xian)，當銅線(xian)與伏打電(dian)(dian)池接通時，繞(rao)在U型鐵(tie)(tie)(tie)(tie)棒(bang)(bang)上(shang)的(de)銅線(xian)圈(quan)即產生(sheng)了(le)密集的(de)磁(ci)場(chang)，這樣就使U型鐵(tie)(tie)(tie)(tie)棒(bang)(bang)變(bian)成了(le)一(yi)塊“電(dian)(dian)磁(ci)鐵(tie)(tie)(tie)(tie)”。這種電(dian)(dian)磁(ci)鐵(tie)(tie)(tie)(tie)上(shang)的(de)磁(ci)能要(yao)比永磁(ci)能大放多倍(bei)，它能吸(xi)起(qi)比它重(zhong)20倍(bei)的(de)鐵(tie)(tie)(tie)(tie)塊，而當電(dian)(dian)源切斷后，U型鐵(tie)(tie)(tie)(tie)棒(bang)(bang)就什么鐵(tie)(tie)(tie)(tie)塊也吸(xi)不(bu)住，重(zhong)新成為一(yi)根(gen)普通的(de)鐵(tie)(tie)(tie)(tie)棒(bang)(bang)。

斯特金的(de)電磁(ci)鐵發(fa)明，使(shi)人們看到了把(ba)電能轉(zhuan)化(hua)為磁(ci)能的(de)光明前景，這(zhe)一(yi)發(fa)明很快(kuai)在(zai)英(ying)國、美國以及西歐一(yi)些沿(yan)海國家傳播開來。

1829年，美國(guo)電(dian)學家亨利對斯特金電(dian)磁(ci)(ci)鐵裝置(zhi)進行了(le)(le)一(yi)些革(ge)新，絕緣導(dao)線代替裸銅(tong)導(dao)線，因此不必擔心被(bei)銅(tong)導(dao)線過分靠(kao)近而短(duan)路。由于(yu)導(dao)線有了(le)(le)絕緣層，就可以將它(ta)們一(yi)圈圈地(di)緊緊地(di)繞(rao)在一(yi)起(qi)，由于(yu)線圈越密集，產生的磁(ci)(ci)場就越強，這樣(yang)就大大提高了(le)(le)把電(dian)能(neng)轉化(hua)為磁(ci)(ci)能(neng)的能(neng)力。到了(le)(le)1831年，亨利試(shi)制出了(le)(le)一(yi)塊更新的電(dian)磁(ci)(ci)鐵，雖然它(ta)的體積并不大，但它(ta)能(neng)吸(xi)起(qi)1噸重的鐵塊。

電(dian)(dian)(dian)(dian)(dian)磁鐵(tie)(tie)內部帶(dai)有鐵(tie)(tie)心的、利用(yong)通有電(dian)(dian)(dian)(dian)(dian)流的線(xian)圈(quan)(quan)使其像磁鐵(tie)(tie)一樣(yang)具有磁性(xing)(xing)的裝置叫做電(dian)(dian)(dian)(dian)(dian)磁鐵(tie)(tie)，通常制(zhi)成條形(xing)或(huo)蹄形(xing)。鐵(tie)(tie)心要用(yong)容(rong)易磁化，又容(rong)易消失磁性(xing)(xing)的軟鐵(tie)(tie)或(huo)硅鋼來制(zhi)做。這樣(yang)的電(dian)(dian)(dian)(dian)(dian)磁鐵(tie)(tie)在通電(dian)(dian)(dian)(dian)(dian)時(shi)有磁性(xing)(xing)，斷(duan)電(dian)(dian)(dian)(dian)(dian)后就(jiu)隨(sui)之消失。 電(dian)(dian)(dian)(dian)(dian)磁鐵(tie)(tie)有許(xu)多優(you)點：電(dian)(dian)(dian)(dian)(dian)磁鐵(tie)(tie)磁性(xing)(xing)的有無，可以用(yong)通、斷(duan)電(dian)(dian)(dian)(dian)(dian)流控(kong)制(zhi)。磁性(xing)(xing)的大小(xiao)可以用(yong)電(dian)(dian)(dian)(dian)(dian)流的強弱(ruo)或(huo)線(xian)圈(quan)(quan)的匝數(shu)來控(kong)制(zhi)。

電磁鐵的主要特點

1、采用全密(mi)封結構，防(fang)潮性能(neng)好(hao)。

2、經計算機優化設(she)計，結構合理(li)、自重輕、吸(xi)力大(da)、能耗低(di)。

3、勵磁線圈(quan)經特別工藝處理，提高了線圈(quan)的電器和機械性能，絕(jue)緣資料熱等級(ji)到達C級(ji)，運用壽命長(chang)。

4、普通型(xing)電磁鐵的額定通電持續率由曩昔的50%提(ti)高到60%，提(ti)高了(le)電磁鐵的運用功(gong)率。

5、超高(gao)溫型(xing)電磁(ci)鐵采用獨特隔(ge)熱(re)方式，其間被(bei)吸物(wu)溫度有曩昔的(de)600℃提高(gao)700℃，擴大了(le)電磁(ci)鐵的(de)適(shi)用范圍(wei)。

6、裝(zhuang)置、運轉、保護簡潔(jie)。

電磁鐵工作原理

將電(dian)(dian)(dian)磁(ci)(ci)(ci)能(neng)變換為機械(xie)能(neng)以(yi)實現吸(xi)合(he)作功的(de)一種電(dian)(dian)(dian)器(qi)(qi)。通常由軟磁(ci)(ci)(ci)材料制成(cheng)(cheng)的(de)鐵(tie)心(xin)、銜鐵(tie)和(he)勵磁(ci)(ci)(ci)繞(rao)組組成(cheng)(cheng)。當勵磁(ci)(ci)(ci)繞(rao)組通電(dian)(dian)(dian)時，繞(rao)組周(zhou)圍產生磁(ci)(ci)(ci)場，鐵(tie)心(xin)磁(ci)(ci)(ci)化(hua)，并產生電(dian)(dian)(dian)磁(ci)(ci)(ci)吸(xi)力吸(xi)引(yin)銜鐵(tie)，使之(zhi)運(yun)動作功。電(dian)(dian)(dian)磁(ci)(ci)(ci)鐵(tie)主要(yao)用(yong)于(yu)(yu)操動、牽引(yin)機械(xie)裝置，以(yi)達到預期的(de)目的(de)。工(gong)(gong)業上(shang)常用(yong)的(de)電(dian)(dian)(dian)磁(ci)(ci)(ci)鐵(tie)有(you)制動電(dian)(dian)(dian)磁(ci)(ci)(ci)鐵(tie)、牽引(yin)電(dian)(dian)(dian)磁(ci)(ci)(ci)鐵(tie)、起重電(dian)(dian)(dian)磁(ci)(ci)(ci)鐵(tie)和(he)閥用(yong)電(dian)(dian)(dian)磁(ci)(ci)(ci)鐵(tie)等(deng)。此外，屬于(yu)(yu)電(dian)(dian)(dian)磁(ci)(ci)(ci)鐵(tie)類的(de)還有(you)用(yong)以(yi)傳遞或(huo)隔斷兩軸(zhou)(zhou)間的(de)機械(xie)聯(lian)系(xi)的(de)電(dian)(dian)(dian)磁(ci)(ci)(ci)聯(lian)軸(zhou)(zhou)器(qi)(qi);用(yong)在機床工(gong)(gong)作臺上(shang)以(yi)吸(xi)牢磁(ci)(ci)(ci)性材料工(gong)(gong)件(jian)的(de)電(dian)(dian)(dian)磁(ci)(ci)(ci)吸(xi)盤;供高能(neng)物理(li)、核聚變研究、磁(ci)(ci)(ci)流體發電(dian)(dian)(dian)和(he)高速懸浮列車等(deng)方面使用(yong)的(de)、能(neng)產生高達數(shu)十特（斯(si)拉(la)）的(de)磁(ci)(ci)(ci)通密度而幾乎不消(xiao)耗繞(rao)組功率(lv)的(de)超導電(dian)(dian)(dian)磁(ci)(ci)(ci)鐵(tie)等(deng)。

起重電磁鐵

用來吊(diao)運和(he)裝(zhuang)卸鐵(tie)磁(ci)(ci)(ci)性物體的(de)(de)電(dian)磁(ci)(ci)(ci)鐵(tie)。工(gong)業上常用以(yi)吊(diao)運或(huo)裝(zhuang)卸鐵(tie)礦石、鐵(tie)砂、廢鋼(gang)(gang)鐵(tie)、鋼(gang)(gang)錠、鋼(gang)(gang)軌以(yi)及各種鋼(gang)(gang)材和(he)鋼(gang)(gang)質(zhi)工(gong)件(jian)(jian)。起重(zhong)電(dian)磁(ci)(ci)(ci)鐵(tie)通(tong)(tong)常做成圓盤形或(huo)矩形，并帶有內(nei)(nei)磁(ci)(ci)(ci)極(ji)和(he)外(wai)磁(ci)(ci)(ci)極(ji)。當勵(li)(li)磁(ci)(ci)(ci)繞(rao)組通(tong)(tong)電(dian)后，內(nei)(nei)外(wai)磁(ci)(ci)(ci)極(ji)均被(bei)(bei)磁(ci)(ci)(ci)化，吸(xi)引鋼(gang)(gang)質(zhi)材料或(huo)工(gong)件(jian)(jian)（相(xiang)當于(yu)一(yi)般(ban)電(dian)磁(ci)(ci)(ci)鐵(tie)中的(de)(de)銜鐵(tie)），形成一(yi)個閉合的(de)(de)磁(ci)(ci)(ci)路。為保(bao)護勵(li)(li)磁(ci)(ci)(ci)繞(rao)組，使之(zhi)不因磁(ci)(ci)(ci)極(ji)與被(bei)(bei)吸(xi)引物體間(jian)的(de)(de)機械(xie)撞擊所(suo)損傷，起重(zhong)電(dian)磁(ci)(ci)(ci)鐵(tie)通(tong)(tong)常采用甲殼(ke)式結構，并且采用直流(liu)勵(li)(li)磁(ci)(ci)(ci)。

牽引電磁鐵

供牽(qian)引(yin)(yin)和推斥機械裝(zhuang)(zhuang)置用(yong)(yong)的(de)(de)一種電(dian)(dian)磁(ci)鐵(tie)。主要用(yong)(yong)于(yu)各種自動設備中，以實現遠距(ju)離(li)控(kong)制(zhi)。為了能夠(gou)在(zai)長行程下獲得(de)較大的(de)(de)電(dian)(dian)磁(ci)吸(xi)(xi)(xi)(xi)力，牽(qian)引(yin)(yin)電(dian)(dian)磁(ci)鐵(tie)一般采用(yong)(yong)吸(xi)(xi)(xi)(xi)引(yin)(yin)特(te)性比較平坦的(de)(de)甲殼(ke)式結構。其內部(bu)裝(zhuang)(zhuang)有(you)(you)鐵(tie)心(xin)(xin)、銜鐵(tie)和勵(li)磁(ci)線圈。使用(yong)(yong)時，將鐵(tie)心(xin)(xin)固定在(zai)機械裝(zhuang)(zhuang)置的(de)(de)靜止部(bu)件上，銜鐵(tie)則連接在(zai)牽(qian)引(yin)(yin)桿上。當勵(li)磁(ci)繞組通電(dian)(dian)后(hou)，鐵(tie)心(xin)(xin)被磁(ci)化，產生電(dian)(dian)磁(ci)吸(xi)(xi)(xi)(xi)力吸(xi)(xi)(xi)(xi)引(yin)(yin)銜鐵(tie)，后(hou)者則通過牽(qian)引(yin)(yin)桿來操縱所(suo)控(kong)制(zhi)的(de)(de)機械裝(zhuang)(zhuang)置的(de)(de)機構。為了適(shi)應不同控(kong)制(zhi)對象(xiang)的(de)(de)需(xu)要，牽(qian)引(yin)(yin)電(dian)(dian)磁(ci)鐵(tie)有(you)(you)拉動式和推動式兩種，但都不具(ju)備復位裝(zhuang)(zhuang)置。牽(qian)引(yin)(yin)電(dian)(dian)磁(ci)鐵(tie)的(de)(de)主要技術指標為一定行程下的(de)(de)電(dian)(dian)磁(ci)吸(xi)(xi)(xi)(xi)力、操作頻率(lv)和壽命(ming)。

制動電磁鐵

作(zuo)(zuo)機械(xie)制(zhi)(zhi)(zhi)(zhi)動用(yong)(yong)的(de)(de)(de)(de)(de)一(yi)種電(dian)(dian)(dian)(dian)(dian)磁(ci)鐵(tie)(tie)(tie)。主要(yao)(yao)用(yong)(yong)于電(dian)(dian)(dian)(dian)(dian)力(li)驅(qu)動裝置和(he)(he)起重運輸(shu)設(she)備(bei)中(zhong)，并(bing)與(yu)制(zhi)(zhi)(zhi)(zhi)動器(qi)配(pei)合(he)使(shi)(shi)用(yong)(yong)，使(shi)(shi)電(dian)(dian)(dian)(dian)(dian)動機準確停車和(he)(he)懸吊(diao)著的(de)(de)(de)(de)(de)重物不(bu)致墜落。制(zhi)(zhi)(zhi)(zhi)動電(dian)(dian)(dian)(dian)(dian)磁(ci)鐵(tie)(tie)(tie)按銜(xian)(xian)鐵(tie)(tie)(tie)行(xing)(xing)程(cheng)(cheng)分為長行(xing)(xing)程(cheng)(cheng)和(he)(he)短(duan)行(xing)(xing)程(cheng)(cheng)兩類(lei);按勵磁(ci)方式分為直流和(he)(he)交(jiao)流、并(bing)勵和(he)(he)串勵以及(ji)單相(xiang)和(he)(he)三(san)相(xiang)等(deng)種類(lei)。制(zhi)(zhi)(zhi)(zhi)動電(dian)(dian)(dian)(dian)(dian)磁(ci)鐵(tie)(tie)(tie)的(de)(de)(de)(de)(de)工作(zuo)(zuo)原理是(shi)：當電(dian)(dian)(dian)(dian)(dian)磁(ci)鐵(tie)(tie)(tie)的(de)(de)(de)(de)(de)繞組通(tong)(tong)(tong)電(dian)(dian)(dian)(dian)(dian)后，銜(xian)(xian)鐵(tie)(tie)(tie)被(bei)吸向鐵(tie)(tie)(tie)心(xin)，并(bing)通(tong)(tong)(tong)過制(zhi)(zhi)(zhi)(zhi)動器(qi)中(zhong)的(de)(de)(de)(de)(de)停檔壓(ya)迫制(zhi)(zhi)(zhi)(zhi)動桿，使(shi)(shi)之(zhi)移動，從(cong)而迫使(shi)(shi)制(zhi)(zhi)(zhi)(zhi)動器(qi)松(song)閘。切斷線(xian)圈電(dian)(dian)(dian)(dian)(dian)源后，制(zhi)(zhi)(zhi)(zhi)動桿在彈簧作(zuo)(zuo)用(yong)(yong)下使(shi)(shi)銜(xian)(xian)鐵(tie)(tie)(tie)脫離磁(ci)軛，而制(zhi)(zhi)(zhi)(zhi)動器(qi)則將(jiang)機構(gou)剎(cha)住。制(zhi)(zhi)(zhi)(zhi)動電(dian)(dian)(dian)(dian)(dian)磁(ci)鐵(tie)(tie)(tie)的(de)(de)(de)(de)(de)主要(yao)(yao)技(ji)術參數是(shi)行(xing)(xing)程(cheng)(cheng)、一(yi)定行(xing)(xing)程(cheng)(cheng)下的(de)(de)(de)(de)(de)電(dian)(dian)(dian)(dian)(dian)磁(ci)吸力(li)、操作(zuo)(zuo)頻率(lv)(lv)和(he)(he)通(tong)(tong)(tong)電(dian)(dian)(dian)(dian)(dian)持續(xu)(xu)率(lv)(lv)。操作(zuo)(zuo)頻率(lv)(lv)是(shi)指(zhi)每(mei)小時操作(zuo)(zuo)的(de)(de)(de)(de)(de)次數;通(tong)(tong)(tong)電(dian)(dian)(dian)(dian)(dian)持續(xu)(xu)率(lv)(lv)是(shi)指(zhi)每(mei)次通(tong)(tong)(tong)電(dian)(dian)(dian)(dian)(dian)時間(jian)與(yu)每(mei)次通(tong)(tong)(tong)電(dian)(dian)(dian)(dian)(dian)及(ji)不(bu)通(tong)(tong)(tong)電(dian)(dian)(dian)(dian)(dian)時間(jian)之(zhi)和(he)(he)的(de)(de)(de)(de)(de)百分比。使(shi)(shi)用(yong)(yong)中(zhong)，制(zhi)(zhi)(zhi)(zhi)動電(dian)(dian)(dian)(dian)(dian)磁(ci)鐵(tie)(tie)(tie)與(yu)瓦(wa)式制(zhi)(zhi)(zhi)(zhi)動器(qi)相(xiang)配(pei)合(he)時用(yong)(yong)短(duan)行(xing)(xing)程(cheng)(cheng)類(lei);與(yu)皮帶(dai)制(zhi)(zhi)(zhi)(zhi)動器(qi)相(xiang)配(pei)合(he)時用(yong)(yong)長行(xing)(xing)程(cheng)(cheng)類(lei)。制(zhi)(zhi)(zhi)(zhi)動電(dian)(dian)(dian)(dian)(dian)磁(ci)鐵(tie)(tie)(tie)通(tong)(tong)(tong)過液(ye)壓(ya)方式將(jiang)電(dian)(dian)(dian)(dian)(dian)磁(ci)力(li)傳遞給制(zhi)(zhi)(zhi)(zhi)動機構(gou)的(de)(de)(de)(de)(de)稱液(ye)壓(ya)制(zhi)(zhi)(zhi)(zhi)動電(dian)(dian)(dian)(dian)(dian)磁(ci)鐵(tie)(tie)(tie)。

閥用電磁鐵

供遠距(ju)離操作(zuo)各種(zhong)液壓、氣動(dong)系統閥(fa)(fa)(fa)(fa)門(men)的(de)(de)電(dian)(dian)磁(ci)鐵(tie)。常(chang)用于各種(zhong)金(jin)屬(shu)切削機床中。閥(fa)(fa)(fa)(fa)用電(dian)(dian)磁(ci)鐵(tie)不設復位裝(zhuang)置(zhi)，而由閥(fa)(fa)(fa)(fa)體中的(de)(de)彈(dan)簧使(shi)(shi)之復位。當電(dian)(dian)磁(ci)鐵(tie)的(de)(de)勵(li)磁(ci)繞組通過電(dian)(dian)流時，電(dian)(dian)磁(ci)吸(xi)力(li)即(ji)克服彈(dan)簧阻力(li)，使(shi)(shi)閥(fa)(fa)(fa)(fa)體的(de)(de)推桿移(yi)動(dong)，將閥(fa)(fa)(fa)(fa)門(men)開啟;當勵(li)磁(ci)繞組斷電(dian)(dian)后，在(zai)復位彈(dan)簧作(zuo)用下，閥(fa)(fa)(fa)(fa)體推桿便推動(dong)銜(xian)鐵(tie)，使(shi)(shi)其移(yi)動(dong)額定行程處，閥(fa)(fa)(fa)(fa)門(men)關閉。閥(fa)(fa)(fa)(fa)用電(dian)(dian)磁(ci)鐵(tie)分為濕(shi)式和干式兩(liang)種(zhong)。濕(shi)式閥(fa)(fa)(fa)(fa)用電(dian)(dian)磁(ci)鐵(tie)的(de)(de)銜(xian)鐵(tie)在(zai)液壓油中工(gong)作(zuo)，由于油的(de)(de)冷卻(que)作(zuo)用，使(shi)(shi)其與具有相(xiang)同(tong)吸(xi)力(li)的(de)(de)電(dian)(dian)磁(ci)鐵(tie)相(xiang)比，有較小的(de)(de)尺寸。

電磁鐵的應用

門(men)禁：為什么門(men)禁可(ke)(ke)以在沒刷卡(ka)時把(ba)門(men)牢牢的(de)(de)“抓住(zhu)”？原來單(dan)元門(men)是由鋼材料做成(cheng)的(de)(de)，那個金屬(shu)體(ti)在通電時可(ke)(ke)以產(chan)生(sheng)強大的(de)(de)磁(ci)(ci)場，產(chan)生(sheng)的(de)(de)磁(ci)(ci)力(li)能把(ba)門(men)牢牢的(de)(de)吸住(zhu)，而(er)刷卡(ka)的(de)(de)瞬間，切(qie)斷電流，金屬(shu)體(ti)失去磁(ci)(ci)性，我(wo)們就可(ke)(ke)以打開門(men)了(le)。那個金屬(shu)體(ti)其實是一塊電磁(ci)(ci)鐵。

電(dian)磁(ci)起(qi)重(zhong)機(ji)(ji)：最直接的應用之一(yi)是電(dian)磁(ci)起(qi)重(zhong)機(ji)(ji)。電(dian)磁(ci)鐵(tie)安裝在(zai)吊車上，通電(dian)后吸起(qi)大(da)量鋼鐵(tie)，移動(dong)到另一(yi)個位置(zhi)后切斷電(dian)流，鋼鐵(tie)被放下，免(mian)去了打捆的麻煩(fan)。大(da)型電(dian)磁(ci)起(qi)重(zhong)機(ji)(ji)一(yi)次(ci)可以吊起(qi)幾噸鋼材。

在電動機(ji)、發電機(ji)、電鈴和(he)電磁繼電器里也用到(dao)電磁鐵(tie)。全(quan)自動洗衣(yi)機(ji)的(de)進水、排水閥(fa)(fa)門，衛(wei)生間里感應式沖水器的(de)閥(fa)(fa)門，也都(dou)是(shi)由(you)電磁鐵(tie)控制的(de)。

電(dian)磁(ci)(ci)鐵(tie)的另一個應(ying)用是(shi)產(chan)生強磁(ci)(ci)場。現(xian)代技術中很多地方需要的強磁(ci)(ci)場都由電(dian)磁(ci)(ci)鐵(tie)提供，如(ru)大型電(dian)動機(ji)、發電(dian)機(ji)、磁(ci)(ci)療設備等。