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。這實際上是四川電磁鐵原理(li)的(de)(de)(de)(de)最初發現。1823年，斯特(te)金(jin)也做了一次(ci)類(lei)似的(de)(de)(de)(de)實驗：他在一根并非是磁鐵(tie)棒(bang)的(de)(de)(de)(de)U型(xing)鐵(tie)棒(bang)上繞(rao)了18圈(quan)銅(tong)裸線(xian)，當(dang)銅(tong)線(xian)與伏(fu)打電(dian)(dian)池接(jie)通時，繞(rao)在U型(xing)鐵(tie)棒(bang)上的(de)(de)(de)(de)銅(tong)線(xian)圈(quan)即產生了密集的(de)(de)(de)(de)磁場，這樣就使U型(xing)鐵(tie)棒(bang)變成(cheng)了一塊“電(dian)(dian)磁鐵(tie)”。這種電(dian)(dian)磁鐵(tie)上的(de)(de)(de)(de)磁能(neng)要(yao)比永(yong)磁能(neng)大放多倍，它(ta)(ta)能(neng)吸起比它(ta)(ta)重20倍的(de)(de)(de)(de)鐵(tie)塊，而當(dang)電(dian)(dian)源切斷后，U型(xing)鐵(tie)棒(bang)就什(shen)么鐵(tie)塊也吸不住，重新(xin)成(cheng)為一根普通的(de)(de)(de)(de)鐵(tie)棒(bang)。

斯(si)特金的(de)電(dian)磁(ci)鐵發明(ming)，使人(ren)們看到了(le)把電(dian)能轉化為磁(ci)能的(de)光明(ming)前景，這一發明(ming)很(hen)快(kuai)在英國(guo)、美國(guo)以及西歐一些沿海國(guo)家(jia)傳播開來。

1829年，美國電學家亨利對(dui)斯(si)特金電磁鐵(tie)(tie)裝置(zhi)進行了一(yi)些革新(xin)，絕緣導線代替裸銅導線，因此不必擔(dan)心被銅導線過(guo)分靠近(jin)而短路。由(you)于導線有了絕緣層(ceng)，就(jiu)(jiu)可以(yi)將(jiang)它們一(yi)圈圈地(di)緊(jin)緊(jin)地(di)繞在一(yi)起，由(you)于線圈越密集(ji)，產生的(de)磁場就(jiu)(jiu)越強，這樣(yang)就(jiu)(jiu)大(da)大(da)提高(gao)了把電能(neng)(neng)轉(zhuan)化(hua)為磁能(neng)(neng)的(de)能(neng)(neng)力。到了1831年，亨利試制出(chu)了一(yi)塊更新(xin)的(de)電磁鐵(tie)(tie)，雖然它的(de)體積并不大(da)，但它能(neng)(neng)吸起1噸(dun)重的(de)鐵(tie)(tie)塊。

電(dian)(dian)磁(ci)鐵(tie)(tie)(tie)(tie)內(nei)部帶有(you)(you)(you)鐵(tie)(tie)(tie)(tie)心(xin)的(de)、利用(yong)(yong)(yong)通(tong)有(you)(you)(you)電(dian)(dian)流(liu)的(de)線圈(quan)使其像磁(ci)鐵(tie)(tie)(tie)(tie)一樣具有(you)(you)(you)磁(ci)性(xing)的(de)裝置叫做(zuo)(zuo)電(dian)(dian)磁(ci)鐵(tie)(tie)(tie)(tie)，通(tong)常制(zhi)(zhi)成條形或蹄形。鐵(tie)(tie)(tie)(tie)心(xin)要用(yong)(yong)(yong)容(rong)易(yi)磁(ci)化，又容(rong)易(yi)消失磁(ci)性(xing)的(de)軟鐵(tie)(tie)(tie)(tie)或硅鋼來制(zhi)(zhi)做(zuo)(zuo)。這(zhe)樣的(de)電(dian)(dian)磁(ci)鐵(tie)(tie)(tie)(tie)在通(tong)電(dian)(dian)時有(you)(you)(you)磁(ci)性(xing)，斷(duan)電(dian)(dian)后就隨之消失。 電(dian)(dian)磁(ci)鐵(tie)(tie)(tie)(tie)有(you)(you)(you)許多優(you)點：電(dian)(dian)磁(ci)鐵(tie)(tie)(tie)(tie)磁(ci)性(xing)的(de)有(you)(you)(you)無，可(ke)以(yi)用(yong)(yong)(yong)通(tong)、斷(duan)電(dian)(dian)流(liu)控制(zhi)(zhi)。磁(ci)性(xing)的(de)大小(xiao)可(ke)以(yi)用(yong)(yong)(yong)電(dian)(dian)流(liu)的(de)強(qiang)弱或線圈(quan)的(de)匝數來控制(zhi)(zhi)。

電磁鐵的主要特點

1、采用全(quan)密封結構，防潮性能好。

2、經(jing)計(ji)算機優(you)化設計(ji)，結構合理、自(zi)重輕、吸力大、能耗低。

3、勵磁線圈經特別工藝處理(li)，提高了線圈的電器和機械(xie)性能(neng)，絕緣資(zi)料(liao)熱等級到達C級，運用壽命長。

4、普通型電(dian)磁鐵的(de)額定通電(dian)持續(xu)率由曩昔(xi)的(de)50%提(ti)高到(dao)60%，提(ti)高了電(dian)磁鐵的(de)運(yun)用(yong)功率。

5、超高溫型電磁鐵(tie)采用獨(du)特隔熱(re)方(fang)式，其間被吸物溫度(du)有曩(nang)昔的(de)600℃提高700℃，擴大(da)了電磁鐵(tie)的(de)適用范圍。

6、裝置(zhi)、運轉、保護簡潔。

電磁鐵工作原理

將(jiang)電(dian)(dian)磁(ci)(ci)(ci)能變換為機(ji)(ji)械(xie)能以(yi)實(shi)現吸(xi)合作功的(de)(de)一種電(dian)(dian)器(qi)。通(tong)常由軟磁(ci)(ci)(ci)材料制(zhi)(zhi)成(cheng)的(de)(de)鐵(tie)(tie)心、銜鐵(tie)(tie)和勵(li)磁(ci)(ci)(ci)繞組(zu)組(zu)成(cheng)。當勵(li)磁(ci)(ci)(ci)繞組(zu)通(tong)電(dian)(dian)時，繞組(zu)周圍(wei)產生磁(ci)(ci)(ci)場，鐵(tie)(tie)心磁(ci)(ci)(ci)化，并產生電(dian)(dian)磁(ci)(ci)(ci)吸(xi)力(li)吸(xi)引(yin)銜鐵(tie)(tie)，使之(zhi)運動(dong)作功。電(dian)(dian)磁(ci)(ci)(ci)鐵(tie)(tie)主要用于(yu)操動(dong)、牽引(yin)機(ji)(ji)械(xie)裝置，以(yi)達(da)到預期的(de)(de)目的(de)(de)。工(gong)業上常用的(de)(de)電(dian)(dian)磁(ci)(ci)(ci)鐵(tie)(tie)有制(zhi)(zhi)動(dong)電(dian)(dian)磁(ci)(ci)(ci)鐵(tie)(tie)、牽引(yin)電(dian)(dian)磁(ci)(ci)(ci)鐵(tie)(tie)、起(qi)重電(dian)(dian)磁(ci)(ci)(ci)鐵(tie)(tie)和閥(fa)用電(dian)(dian)磁(ci)(ci)(ci)鐵(tie)(tie)等。此外，屬(shu)于(yu)電(dian)(dian)磁(ci)(ci)(ci)鐵(tie)(tie)類的(de)(de)還有用以(yi)傳遞或(huo)隔斷兩軸(zhou)(zhou)間的(de)(de)機(ji)(ji)械(xie)聯系的(de)(de)電(dian)(dian)磁(ci)(ci)(ci)聯軸(zhou)(zhou)器(qi);用在機(ji)(ji)床(chuang)工(gong)作臺上以(yi)吸(xi)牢磁(ci)(ci)(ci)性材料工(gong)件的(de)(de)電(dian)(dian)磁(ci)(ci)(ci)吸(xi)盤;供高能物理、核(he)聚(ju)變研(yan)究、磁(ci)(ci)(ci)流體發電(dian)(dian)和高速(su)懸(xuan)浮列車(che)等方面使用的(de)(de)、能產生高達(da)數十特（斯拉(la)）的(de)(de)磁(ci)(ci)(ci)通(tong)密(mi)度而幾乎不消耗(hao)繞組(zu)功率的(de)(de)超(chao)導電(dian)(dian)磁(ci)(ci)(ci)鐵(tie)(tie)等。

起重電磁鐵

用來(lai)吊(diao)運和裝卸(xie)鐵(tie)(tie)(tie)(tie)磁(ci)(ci)(ci)(ci)(ci)(ci)性物體的(de)電(dian)磁(ci)(ci)(ci)(ci)(ci)(ci)鐵(tie)(tie)(tie)(tie)。工(gong)業(ye)上常(chang)用以(yi)吊(diao)運或(huo)裝卸(xie)鐵(tie)(tie)(tie)(tie)礦石、鐵(tie)(tie)(tie)(tie)砂、廢鋼(gang)鐵(tie)(tie)(tie)(tie)、鋼(gang)錠、鋼(gang)軌以(yi)及各種鋼(gang)材(cai)和鋼(gang)質工(gong)件(jian)。起重電(dian)磁(ci)(ci)(ci)(ci)(ci)(ci)鐵(tie)(tie)(tie)(tie)通常(chang)做成圓(yuan)盤形(xing)或(huo)矩形(xing)，并(bing)帶有內磁(ci)(ci)(ci)(ci)(ci)(ci)極和外磁(ci)(ci)(ci)(ci)(ci)(ci)極。當勵磁(ci)(ci)(ci)(ci)(ci)(ci)繞組(zu)通電(dian)后，內外磁(ci)(ci)(ci)(ci)(ci)(ci)極均(jun)被磁(ci)(ci)(ci)(ci)(ci)(ci)化，吸引鋼(gang)質材(cai)料或(huo)工(gong)件(jian)（相當于一般電(dian)磁(ci)(ci)(ci)(ci)(ci)(ci)鐵(tie)(tie)(tie)(tie)中的(de)銜鐵(tie)(tie)(tie)(tie)），形(xing)成一個(ge)閉合的(de)磁(ci)(ci)(ci)(ci)(ci)(ci)路(lu)。為保護(hu)勵磁(ci)(ci)(ci)(ci)(ci)(ci)繞組(zu)，使之不(bu)因磁(ci)(ci)(ci)(ci)(ci)(ci)極與被吸引物體間(jian)的(de)機械撞擊(ji)所(suo)損(sun)傷，起重電(dian)磁(ci)(ci)(ci)(ci)(ci)(ci)鐵(tie)(tie)(tie)(tie)通常(chang)采用甲殼式結構，并(bing)且采用直流勵磁(ci)(ci)(ci)(ci)(ci)(ci)。

牽引電磁鐵

供牽(qian)(qian)引(yin)(yin)(yin)和(he)(he)推斥機械裝(zhuang)置(zhi)用(yong)的一種(zhong)電磁(ci)鐵(tie)(tie)(tie)。主(zhu)要(yao)用(yong)于各種(zhong)自動設備中(zhong)，以實現遠距(ju)離控(kong)制(zhi)(zhi)。為(wei)了能(neng)夠在長(chang)行程下獲得較(jiao)大的電磁(ci)吸(xi)(xi)力，牽(qian)(qian)引(yin)(yin)(yin)電磁(ci)鐵(tie)(tie)(tie)一般采用(yong)吸(xi)(xi)引(yin)(yin)(yin)特性比較(jiao)平坦的甲殼式結構。其內部裝(zhuang)有鐵(tie)(tie)(tie)心(xin)(xin)、銜(xian)鐵(tie)(tie)(tie)和(he)(he)勵磁(ci)線圈。使用(yong)時，將(jiang)鐵(tie)(tie)(tie)心(xin)(xin)固定(ding)(ding)在機械裝(zhuang)置(zhi)的靜止(zhi)部件上(shang)，銜(xian)鐵(tie)(tie)(tie)則(ze)連接在牽(qian)(qian)引(yin)(yin)(yin)桿上(shang)。當勵磁(ci)繞組(zu)通(tong)(tong)電后，鐵(tie)(tie)(tie)心(xin)(xin)被磁(ci)化，產生電磁(ci)吸(xi)(xi)力吸(xi)(xi)引(yin)(yin)(yin)銜(xian)鐵(tie)(tie)(tie)，后者(zhe)則(ze)通(tong)(tong)過牽(qian)(qian)引(yin)(yin)(yin)桿來操縱所(suo)控(kong)制(zhi)(zhi)的機械裝(zhuang)置(zhi)的機構。為(wei)了適應不(bu)同控(kong)制(zhi)(zhi)對象的需要(yao)，牽(qian)(qian)引(yin)(yin)(yin)電磁(ci)鐵(tie)(tie)(tie)有拉動式和(he)(he)推動式兩種(zhong)，但(dan)都不(bu)具備復(fu)位裝(zhuang)置(zhi)。牽(qian)(qian)引(yin)(yin)(yin)電磁(ci)鐵(tie)(tie)(tie)的主(zhu)要(yao)技術指標為(wei)一定(ding)(ding)行程下的電磁(ci)吸(xi)(xi)力、操作頻(pin)率(lv)和(he)(he)壽(shou)命。

制動電磁鐵

作機械制(zhi)(zhi)(zhi)(zhi)(zhi)動(dong)(dong)(dong)(dong)(dong)(dong)(dong)用(yong)的(de)(de)(de)(de)一種電(dian)(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)鐵(tie)(tie)。主(zhu)要用(yong)于電(dian)(dian)(dian)(dian)(dian)力(li)驅動(dong)(dong)(dong)(dong)(dong)(dong)(dong)裝置和(he)(he)(he)(he)起重運輸設備中(zhong)，并與制(zhi)(zhi)(zhi)(zhi)(zhi)動(dong)(dong)(dong)(dong)(dong)(dong)(dong)器(qi)配合(he)使用(yong)，使電(dian)(dian)(dian)(dian)(dian)動(dong)(dong)(dong)(dong)(dong)(dong)(dong)機準確停車和(he)(he)(he)(he)懸吊著的(de)(de)(de)(de)重物(wu)不(bu)致墜落(luo)。制(zhi)(zhi)(zhi)(zhi)(zhi)動(dong)(dong)(dong)(dong)(dong)(dong)(dong)電(dian)(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)鐵(tie)(tie)按(an)銜鐵(tie)(tie)行(xing)(xing)程(cheng)分(fen)(fen)為(wei)長(chang)行(xing)(xing)程(cheng)和(he)(he)(he)(he)短行(xing)(xing)程(cheng)兩類(lei)(lei);按(an)勵(li)磁(ci)(ci)(ci)方式(shi)分(fen)(fen)為(wei)直流和(he)(he)(he)(he)交流、并勵(li)和(he)(he)(he)(he)串勵(li)以及(ji)單相(xiang)(xiang)和(he)(he)(he)(he)三相(xiang)(xiang)等(deng)種類(lei)(lei)。制(zhi)(zhi)(zhi)(zhi)(zhi)動(dong)(dong)(dong)(dong)(dong)(dong)(dong)電(dian)(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)鐵(tie)(tie)的(de)(de)(de)(de)工(gong)作原理(li)是：當電(dian)(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)鐵(tie)(tie)的(de)(de)(de)(de)繞組通(tong)(tong)(tong)(tong)電(dian)(dian)(dian)(dian)(dian)后，銜鐵(tie)(tie)被吸向鐵(tie)(tie)心，并通(tong)(tong)(tong)(tong)過制(zhi)(zhi)(zhi)(zhi)(zhi)動(dong)(dong)(dong)(dong)(dong)(dong)(dong)器(qi)中(zhong)的(de)(de)(de)(de)停檔壓(ya)迫制(zhi)(zhi)(zhi)(zhi)(zhi)動(dong)(dong)(dong)(dong)(dong)(dong)(dong)桿，使之(zhi)移動(dong)(dong)(dong)(dong)(dong)(dong)(dong)，從而迫使制(zhi)(zhi)(zhi)(zhi)(zhi)動(dong)(dong)(dong)(dong)(dong)(dong)(dong)器(qi)松閘。切斷線圈電(dian)(dian)(dian)(dian)(dian)源后，制(zhi)(zhi)(zhi)(zhi)(zhi)動(dong)(dong)(dong)(dong)(dong)(dong)(dong)桿在彈簧作用(yong)下(xia)使銜鐵(tie)(tie)脫離磁(ci)(ci)(ci)軛，而制(zhi)(zhi)(zhi)(zhi)(zhi)動(dong)(dong)(dong)(dong)(dong)(dong)(dong)器(qi)則(ze)將機構(gou)剎住。制(zhi)(zhi)(zhi)(zhi)(zhi)動(dong)(dong)(dong)(dong)(dong)(dong)(dong)電(dian)(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)鐵(tie)(tie)的(de)(de)(de)(de)主(zhu)要技術參數是行(xing)(xing)程(cheng)、一定行(xing)(xing)程(cheng)下(xia)的(de)(de)(de)(de)電(dian)(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)吸力(li)、操作頻率和(he)(he)(he)(he)通(tong)(tong)(tong)(tong)電(dian)(dian)(dian)(dian)(dian)持續率。操作頻率是指每小(xiao)時(shi)操作的(de)(de)(de)(de)次數;通(tong)(tong)(tong)(tong)電(dian)(dian)(dian)(dian)(dian)持續率是指每次通(tong)(tong)(tong)(tong)電(dian)(dian)(dian)(dian)(dian)時(shi)間與每次通(tong)(tong)(tong)(tong)電(dian)(dian)(dian)(dian)(dian)及(ji)不(bu)通(tong)(tong)(tong)(tong)電(dian)(dian)(dian)(dian)(dian)時(shi)間之(zhi)和(he)(he)(he)(he)的(de)(de)(de)(de)百分(fen)(fen)比。使用(yong)中(zhong)，制(zhi)(zhi)(zhi)(zhi)(zhi)動(dong)(dong)(dong)(dong)(dong)(dong)(dong)電(dian)(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)鐵(tie)(tie)與瓦式(shi)制(zhi)(zhi)(zhi)(zhi)(zhi)動(dong)(dong)(dong)(dong)(dong)(dong)(dong)器(qi)相(xiang)(xiang)配合(he)時(shi)用(yong)短行(xing)(xing)程(cheng)類(lei)(lei);與皮帶制(zhi)(zhi)(zhi)(zhi)(zhi)動(dong)(dong)(dong)(dong)(dong)(dong)(dong)器(qi)相(xiang)(xiang)配合(he)時(shi)用(yong)長(chang)行(xing)(xing)程(cheng)類(lei)(lei)。制(zhi)(zhi)(zhi)(zhi)(zhi)動(dong)(dong)(dong)(dong)(dong)(dong)(dong)電(dian)(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)鐵(tie)(tie)通(tong)(tong)(tong)(tong)過液壓(ya)方式(shi)將電(dian)(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)力(li)傳遞給制(zhi)(zhi)(zhi)(zhi)(zhi)動(dong)(dong)(dong)(dong)(dong)(dong)(dong)機構(gou)的(de)(de)(de)(de)稱液壓(ya)制(zhi)(zhi)(zhi)(zhi)(zhi)動(dong)(dong)(dong)(dong)(dong)(dong)(dong)電(dian)(dian)(dian)(dian)(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(zhong)液壓(ya)、氣動(dong)系統閥(fa)(fa)門的電(dian)(dian)磁(ci)(ci)(ci)鐵(tie)。常用(yong)(yong)于(yu)(yu)各(ge)種(zhong)金屬切(qie)削機床中(zhong)。閥(fa)(fa)用(yong)(yong)電(dian)(dian)磁(ci)(ci)(ci)鐵(tie)不設(she)復(fu)位裝置，而由閥(fa)(fa)體(ti)中(zhong)的彈簧使(shi)(shi)之復(fu)位。當電(dian)(dian)磁(ci)(ci)(ci)鐵(tie)的勵(li)磁(ci)(ci)(ci)繞(rao)組通(tong)過電(dian)(dian)流時，電(dian)(dian)磁(ci)(ci)(ci)吸力(li)(li)即(ji)克服彈簧阻力(li)(li)，使(shi)(shi)閥(fa)(fa)體(ti)的推桿移(yi)動(dong)，將閥(fa)(fa)門開(kai)啟(qi);當勵(li)磁(ci)(ci)(ci)繞(rao)組斷電(dian)(dian)后，在復(fu)位彈簧作(zuo)(zuo)用(yong)(yong)下，閥(fa)(fa)體(ti)推桿便(bian)推動(dong)銜(xian)(xian)鐵(tie)，使(shi)(shi)其移(yi)動(dong)額定行程處，閥(fa)(fa)門關閉。閥(fa)(fa)用(yong)(yong)電(dian)(dian)磁(ci)(ci)(ci)鐵(tie)分為濕(shi)式和(he)干式兩種(zhong)。濕(shi)式閥(fa)(fa)用(yong)(yong)電(dian)(dian)磁(ci)(ci)(ci)鐵(tie)的銜(xian)(xian)鐵(tie)在液壓(ya)油中(zhong)工作(zuo)(zuo)，由于(yu)(yu)油的冷卻(que)作(zuo)(zuo)用(yong)(yong)，使(shi)(shi)其與具有相同吸力(li)(li)的電(dian)(dian)磁(ci)(ci)(ci)鐵(tie)相比，有較小的尺寸。

電磁鐵的應用

門(men)禁：為什么門(men)禁可(ke)(ke)以(yi)在沒刷卡時把門(men)牢(lao)牢(lao)的(de)(de)“抓住”？原來單元門(men)是(shi)由鋼材料做成的(de)(de)，那個金(jin)屬(shu)體(ti)在通電時可(ke)(ke)以(yi)產生(sheng)強大(da)的(de)(de)磁(ci)場(chang)，產生(sheng)的(de)(de)磁(ci)力(li)能把門(men)牢(lao)牢(lao)的(de)(de)吸住，而刷卡的(de)(de)瞬間，切斷電流，金(jin)屬(shu)體(ti)失去磁(ci)性，我們就可(ke)(ke)以(yi)打開門(men)了(le)。那個金(jin)屬(shu)體(ti)其實是(shi)一塊(kuai)電磁(ci)鐵(tie)。

電(dian)(dian)磁起(qi)重機(ji)：最直接的應用之一是(shi)電(dian)(dian)磁起(qi)重機(ji)。電(dian)(dian)磁鐵(tie)安裝(zhuang)在吊(diao)車上，通電(dian)(dian)后吸起(qi)大量鋼鐵(tie)，移動到另一個位置(zhi)后切斷電(dian)(dian)流，鋼鐵(tie)被(bei)放下，免去(qu)了打捆的麻煩(fan)。大型(xing)電(dian)(dian)磁起(qi)重機(ji)一次可以吊(diao)起(qi)幾噸(dun)鋼材。

在電(dian)動機(ji)、發電(dian)機(ji)、電(dian)鈴和(he)電(dian)磁繼電(dian)器(qi)里也用到(dao)電(dian)磁鐵。全自動洗衣(yi)機(ji)的進水、排水閥門，衛生(sheng)間里感應式(shi)沖(chong)水器(qi)的閥門，也都是由電(dian)磁鐵控制的。

電(dian)(dian)磁(ci)鐵的另(ling)一個應用是產生(sheng)強磁(ci)場。現代技術(shu)中很多地方需(xu)要的強磁(ci)場都由電(dian)(dian)磁(ci)鐵提供(gong)，如(ru)大型(xing)電(dian)(dian)動機、發電(dian)(dian)機、磁(ci)療設備等。