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。這實際上是廣東電磁鐵原(yuan)理的最初發現。1823年，斯特金也做(zuo)了一次類似(si)的實驗：他在一根并非是(shi)磁(ci)(ci)(ci)鐵棒的U型鐵棒上(shang)繞(rao)了18圈銅(tong)裸(luo)線，當銅(tong)線與伏(fu)打電池接通(tong)時(shi)，繞(rao)在U型鐵棒上(shang)的銅(tong)線圈即產生(sheng)了密集的磁(ci)(ci)(ci)場，這(zhe)(zhe)樣就(jiu)使U型鐵棒變成了一塊(kuai)“電磁(ci)(ci)(ci)鐵”。這(zhe)(zhe)種(zhong)電磁(ci)(ci)(ci)鐵上(shang)的磁(ci)(ci)(ci)能(neng)要比永磁(ci)(ci)(ci)能(neng)大放多倍，它(ta)能(neng)吸起(qi)比它(ta)重(zhong)20倍的鐵塊(kuai)，而當電源切斷(duan)后，U型鐵棒就(jiu)什(shen)么鐵塊(kuai)也吸不(bu)住，重(zhong)新成為一根普通(tong)的鐵棒。

斯特金的(de)電(dian)磁鐵發明，使人(ren)們看到了把電(dian)能轉化為磁能的(de)光明前景，這一(yi)(yi)發明很快在英國、美國以及西(xi)歐一(yi)(yi)些沿海國家傳播開(kai)來。

1829年(nian)，美(mei)國(guo)電(dian)(dian)學家亨(heng)(heng)利對斯特金電(dian)(dian)磁鐵(tie)裝置進(jin)行了(le)(le)一(yi)些革(ge)新，絕緣導(dao)線(xian)(xian)代替裸(luo)銅導(dao)線(xian)(xian)，因此不必擔心(xin)被(bei)銅導(dao)線(xian)(xian)過(guo)分(fen)靠近而(er)短路。由于導(dao)線(xian)(xian)有了(le)(le)絕緣層，就(jiu)(jiu)可以(yi)將它們一(yi)圈圈地(di)緊緊地(di)繞(rao)在(zai)一(yi)起，由于線(xian)(xian)圈越密(mi)集，產生的磁場就(jiu)(jiu)越強，這樣就(jiu)(jiu)大(da)大(da)提高(gao)了(le)(le)把電(dian)(dian)能(neng)轉化為磁能(neng)的能(neng)力。到了(le)(le)1831年(nian)，亨(heng)(heng)利試制出了(le)(le)一(yi)塊更新的電(dian)(dian)磁鐵(tie)，雖然它的體積并不大(da)，但它能(neng)吸起1噸重的鐵(tie)塊。

電(dian)磁(ci)(ci)(ci)(ci)鐵內部帶有(you)(you)鐵心(xin)的(de)(de)、利用通有(you)(you)電(dian)流(liu)的(de)(de)線(xian)(xian)圈使其像磁(ci)(ci)(ci)(ci)鐵一樣具有(you)(you)磁(ci)(ci)(ci)(ci)性(xing)的(de)(de)裝(zhuang)置(zhi)叫做電(dian)磁(ci)(ci)(ci)(ci)鐵，通常制(zhi)(zhi)成條(tiao)形或蹄形。鐵心(xin)要用容易(yi)磁(ci)(ci)(ci)(ci)化，又容易(yi)消失(shi)磁(ci)(ci)(ci)(ci)性(xing)的(de)(de)軟鐵或硅鋼來制(zhi)(zhi)做。這(zhe)樣的(de)(de)電(dian)磁(ci)(ci)(ci)(ci)鐵在(zai)通電(dian)時(shi)有(you)(you)磁(ci)(ci)(ci)(ci)性(xing)，斷電(dian)后就隨之消失(shi)。 電(dian)磁(ci)(ci)(ci)(ci)鐵有(you)(you)許多優點：電(dian)磁(ci)(ci)(ci)(ci)鐵磁(ci)(ci)(ci)(ci)性(xing)的(de)(de)有(you)(you)無，可以(yi)用通、斷電(dian)流(liu)控制(zhi)(zhi)。磁(ci)(ci)(ci)(ci)性(xing)的(de)(de)大(da)小可以(yi)用電(dian)流(liu)的(de)(de)強(qiang)弱(ruo)或線(xian)(xian)圈的(de)(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(xing)能好(hao)。

2、經計算機優化設計，結構合理、自(zi)重輕、吸力大、能耗低。

3、勵磁線圈(quan)經(jing)特別(bie)工(gong)藝處理(li)，提高了線圈(quan)的電器和機械性能，絕(jue)緣資料熱等級到達C級，運用壽(shou)命長(chang)。

4、普通(tong)型電(dian)(dian)磁鐵的(de)額定通(tong)電(dian)(dian)持(chi)續率由曩昔(xi)的(de)50%提高到60%，提高了電(dian)(dian)磁鐵的(de)運(yun)用功率。

5、超高溫(wen)型電磁(ci)(ci)鐵采(cai)用獨特(te)隔熱(re)方(fang)式(shi)，其間被吸物(wu)溫(wen)度(du)有曩昔的600℃提(ti)高700℃，擴大了電磁(ci)(ci)鐵的適(shi)用范圍。

6、裝置、運轉(zhuan)、保護簡潔。

電磁鐵工作原理

將電(dian)(dian)磁(ci)(ci)能變(bian)換(huan)為機械能以(yi)(yi)實現吸(xi)(xi)合作功(gong)的(de)(de)(de)(de)(de)一種電(dian)(dian)器。通(tong)(tong)常由軟磁(ci)(ci)材料制成的(de)(de)(de)(de)(de)鐵(tie)(tie)心、銜(xian)鐵(tie)(tie)和勵磁(ci)(ci)繞組(zu)組(zu)成。當勵磁(ci)(ci)繞組(zu)通(tong)(tong)電(dian)(dian)時，繞組(zu)周圍產(chan)生磁(ci)(ci)場，鐵(tie)(tie)心磁(ci)(ci)化，并產(chan)生電(dian)(dian)磁(ci)(ci)吸(xi)(xi)力吸(xi)(xi)引(yin)銜(xian)鐵(tie)(tie)，使之運動作功(gong)。電(dian)(dian)磁(ci)(ci)鐵(tie)(tie)主要(yao)用于操(cao)動、牽(qian)引(yin)機械裝置，以(yi)(yi)達到(dao)預期的(de)(de)(de)(de)(de)目的(de)(de)(de)(de)(de)。工(gong)業(ye)上常用的(de)(de)(de)(de)(de)電(dian)(dian)磁(ci)(ci)鐵(tie)(tie)有制動電(dian)(dian)磁(ci)(ci)鐵(tie)(tie)、牽(qian)引(yin)電(dian)(dian)磁(ci)(ci)鐵(tie)(tie)、起重電(dian)(dian)磁(ci)(ci)鐵(tie)(tie)和閥(fa)用電(dian)(dian)磁(ci)(ci)鐵(tie)(tie)等。此(ci)外，屬于電(dian)(dian)磁(ci)(ci)鐵(tie)(tie)類的(de)(de)(de)(de)(de)還有用以(yi)(yi)傳遞(di)或(huo)隔斷兩軸(zhou)間的(de)(de)(de)(de)(de)機械聯系的(de)(de)(de)(de)(de)電(dian)(dian)磁(ci)(ci)聯軸(zhou)器;用在機床(chuang)工(gong)作臺上以(yi)(yi)吸(xi)(xi)牢磁(ci)(ci)性(xing)材料工(gong)件的(de)(de)(de)(de)(de)電(dian)(dian)磁(ci)(ci)吸(xi)(xi)盤;供高(gao)能物理、核聚變(bian)研究、磁(ci)(ci)流(liu)體發(fa)電(dian)(dian)和高(gao)速懸浮列車等方面使用的(de)(de)(de)(de)(de)、能產(chan)生高(gao)達數十特（斯拉）的(de)(de)(de)(de)(de)磁(ci)(ci)通(tong)(tong)密度(du)而幾乎不消耗繞組(zu)功(gong)率(lv)的(de)(de)(de)(de)(de)超(chao)導電(dian)(dian)磁(ci)(ci)鐵(tie)(tie)等。

起重電磁鐵

用來吊(diao)運(yun)和裝卸鐵(tie)(tie)磁(ci)(ci)(ci)性物(wu)體(ti)的(de)(de)電(dian)(dian)磁(ci)(ci)(ci)鐵(tie)(tie)。工業上常(chang)(chang)用以吊(diao)運(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(zhong)鋼(gang)材和鋼(gang)質工件(jian)(jian)。起(qi)重電(dian)(dian)磁(ci)(ci)(ci)鐵(tie)(tie)通常(chang)(chang)做(zuo)成圓盤形或(huo)矩(ju)形，并帶有內(nei)磁(ci)(ci)(ci)極(ji)(ji)和外磁(ci)(ci)(ci)極(ji)(ji)。當勵(li)(li)磁(ci)(ci)(ci)繞組通電(dian)(dian)后，內(nei)外磁(ci)(ci)(ci)極(ji)(ji)均被(bei)(bei)磁(ci)(ci)(ci)化(hua)，吸引(yin)鋼(gang)質材料或(huo)工件(jian)(jian)（相當于(yu)一(yi)般電(dian)(dian)磁(ci)(ci)(ci)鐵(tie)(tie)中(zhong)的(de)(de)銜鐵(tie)(tie)），形成一(yi)個閉(bi)合(he)的(de)(de)磁(ci)(ci)(ci)路(lu)。為保護勵(li)(li)磁(ci)(ci)(ci)繞組，使之(zhi)不因磁(ci)(ci)(ci)極(ji)(ji)與被(bei)(bei)吸引(yin)物(wu)體(ti)間的(de)(de)機械(xie)撞(zhuang)擊所損傷，起(qi)重電(dian)(dian)磁(ci)(ci)(ci)鐵(tie)(tie)通常(chang)(chang)采用甲殼式結構，并且采用直流(liu)勵(li)(li)磁(ci)(ci)(ci)。

牽引電磁鐵

供牽引(yin)(yin)和(he)推斥機(ji)械(xie)裝置(zhi)用(yong)(yong)的一(yi)種(zhong)(zhong)電(dian)(dian)(dian)磁(ci)(ci)(ci)鐵(tie)(tie)(tie)(tie)。主要(yao)用(yong)(yong)于各種(zhong)(zhong)自動設備中(zhong)，以實現遠距離控(kong)制(zhi)。為(wei)了能(neng)夠在長行程下獲得較大(da)的電(dian)(dian)(dian)磁(ci)(ci)(ci)吸(xi)(xi)力(li)，牽引(yin)(yin)電(dian)(dian)(dian)磁(ci)(ci)(ci)鐵(tie)(tie)(tie)(tie)一(yi)般采用(yong)(yong)吸(xi)(xi)引(yin)(yin)特(te)性比較平坦的甲殼式(shi)(shi)結構。其內部裝有鐵(tie)(tie)(tie)(tie)心、銜鐵(tie)(tie)(tie)(tie)和(he)勵(li)磁(ci)(ci)(ci)線圈。使用(yong)(yong)時，將鐵(tie)(tie)(tie)(tie)心固(gu)定在機(ji)械(xie)裝置(zhi)的靜止部件上，銜鐵(tie)(tie)(tie)(tie)則(ze)連接(jie)在牽引(yin)(yin)桿(gan)上。當(dang)勵(li)磁(ci)(ci)(ci)繞組(zu)通(tong)電(dian)(dian)(dian)后(hou)，鐵(tie)(tie)(tie)(tie)心被磁(ci)(ci)(ci)化(hua)，產生電(dian)(dian)(dian)磁(ci)(ci)(ci)吸(xi)(xi)力(li)吸(xi)(xi)引(yin)(yin)銜鐵(tie)(tie)(tie)(tie)，后(hou)者(zhe)則(ze)通(tong)過牽引(yin)(yin)桿(gan)來操(cao)縱所控(kong)制(zhi)的機(ji)械(xie)裝置(zhi)的機(ji)構。為(wei)了適應不同控(kong)制(zhi)對象的需要(yao)，牽引(yin)(yin)電(dian)(dian)(dian)磁(ci)(ci)(ci)鐵(tie)(tie)(tie)(tie)有拉動式(shi)(shi)和(he)推動式(shi)(shi)兩種(zhong)(zhong)，但都不具備復位裝置(zhi)。牽引(yin)(yin)電(dian)(dian)(dian)磁(ci)(ci)(ci)鐵(tie)(tie)(tie)(tie)的主要(yao)技術指標(biao)為(wei)一(yi)定行程下的電(dian)(dian)(dian)磁(ci)(ci)(ci)吸(xi)(xi)力(li)、操(cao)作頻率(lv)和(he)壽(shou)命。

制動電磁鐵

作(zuo)(zuo)機械制(zhi)(zhi)(zhi)(zhi)動(dong)(dong)(dong)(dong)用(yong)的一種電(dian)(dian)(dian)磁(ci)(ci)鐵(tie)(tie)(tie)。主要(yao)用(yong)于電(dian)(dian)(dian)力驅動(dong)(dong)(dong)(dong)裝置和(he)(he)(he)起重運(yun)輸設備中(zhong)，并與制(zhi)(zhi)(zhi)(zhi)動(dong)(dong)(dong)(dong)器(qi)(qi)(qi)配合使(shi)用(yong)，使(shi)電(dian)(dian)(dian)動(dong)(dong)(dong)(dong)機準確停車和(he)(he)(he)懸吊(diao)著的重物不(bu)致墜落。制(zhi)(zhi)(zhi)(zhi)動(dong)(dong)(dong)(dong)電(dian)(dian)(dian)磁(ci)(ci)鐵(tie)(tie)(tie)按(an)銜鐵(tie)(tie)(tie)行(xing)(xing)程(cheng)(cheng)(cheng)分(fen)(fen)為長行(xing)(xing)程(cheng)(cheng)(cheng)和(he)(he)(he)短行(xing)(xing)程(cheng)(cheng)(cheng)兩類(lei);按(an)勵(li)磁(ci)(ci)方(fang)式分(fen)(fen)為直流(liu)和(he)(he)(he)交流(liu)、并勵(li)和(he)(he)(he)串勵(li)以及單相和(he)(he)(he)三相等種類(lei)。制(zhi)(zhi)(zhi)(zhi)動(dong)(dong)(dong)(dong)電(dian)(dian)(dian)磁(ci)(ci)鐵(tie)(tie)(tie)的工作(zuo)(zuo)原理是：當電(dian)(dian)(dian)磁(ci)(ci)鐵(tie)(tie)(tie)的繞組通電(dian)(dian)(dian)后(hou)，銜鐵(tie)(tie)(tie)被吸向鐵(tie)(tie)(tie)心，并通過制(zhi)(zhi)(zhi)(zhi)動(dong)(dong)(dong)(dong)器(qi)(qi)(qi)中(zhong)的停檔壓(ya)(ya)(ya)迫制(zhi)(zhi)(zhi)(zhi)動(dong)(dong)(dong)(dong)桿(gan)，使(shi)之移動(dong)(dong)(dong)(dong)，從而迫使(shi)制(zhi)(zhi)(zhi)(zhi)動(dong)(dong)(dong)(dong)器(qi)(qi)(qi)松閘。切斷(duan)線圈電(dian)(dian)(dian)源后(hou)，制(zhi)(zhi)(zhi)(zhi)動(dong)(dong)(dong)(dong)桿(gan)在(zai)彈簧(huang)作(zuo)(zuo)用(yong)下(xia)使(shi)銜鐵(tie)(tie)(tie)脫離磁(ci)(ci)軛，而制(zhi)(zhi)(zhi)(zhi)動(dong)(dong)(dong)(dong)器(qi)(qi)(qi)則(ze)將(jiang)機構剎住。制(zhi)(zhi)(zhi)(zhi)動(dong)(dong)(dong)(dong)電(dian)(dian)(dian)磁(ci)(ci)鐵(tie)(tie)(tie)的主要(yao)技術參數(shu)是行(xing)(xing)程(cheng)(cheng)(cheng)、一定(ding)行(xing)(xing)程(cheng)(cheng)(cheng)下(xia)的電(dian)(dian)(dian)磁(ci)(ci)吸力、操(cao)作(zuo)(zuo)頻率和(he)(he)(he)通電(dian)(dian)(dian)持(chi)續率。操(cao)作(zuo)(zuo)頻率是指(zhi)(zhi)每小時(shi)(shi)操(cao)作(zuo)(zuo)的次(ci)(ci)數(shu);通電(dian)(dian)(dian)持(chi)續率是指(zhi)(zhi)每次(ci)(ci)通電(dian)(dian)(dian)時(shi)(shi)間與每次(ci)(ci)通電(dian)(dian)(dian)及不(bu)通電(dian)(dian)(dian)時(shi)(shi)間之和(he)(he)(he)的百分(fen)(fen)比(bi)。使(shi)用(yong)中(zhong)，制(zhi)(zhi)(zhi)(zhi)動(dong)(dong)(dong)(dong)電(dian)(dian)(dian)磁(ci)(ci)鐵(tie)(tie)(tie)與瓦式制(zhi)(zhi)(zhi)(zhi)動(dong)(dong)(dong)(dong)器(qi)(qi)(qi)相配合時(shi)(shi)用(yong)短行(xing)(xing)程(cheng)(cheng)(cheng)類(lei);與皮(pi)帶制(zhi)(zhi)(zhi)(zhi)動(dong)(dong)(dong)(dong)器(qi)(qi)(qi)相配合時(shi)(shi)用(yong)長行(xing)(xing)程(cheng)(cheng)(cheng)類(lei)。制(zhi)(zhi)(zhi)(zhi)動(dong)(dong)(dong)(dong)電(dian)(dian)(dian)磁(ci)(ci)鐵(tie)(tie)(tie)通過液(ye)壓(ya)(ya)(ya)方(fang)式將(jiang)電(dian)(dian)(dian)磁(ci)(ci)力傳遞給制(zhi)(zhi)(zhi)(zhi)動(dong)(dong)(dong)(dong)機構的稱液(ye)壓(ya)(ya)(ya)制(zhi)(zhi)(zhi)(zhi)動(dong)(dong)(dong)(dong)電(dian)(dian)(dian)磁(ci)(ci)鐵(tie)(tie)(tie)。

閥用電磁鐵

供遠距離(li)操作(zuo)(zuo)各種液壓、氣動(dong)(dong)系統(tong)閥(fa)(fa)(fa)門的電(dian)(dian)磁(ci)鐵(tie)。常用于(yu)各種金屬切削(xue)機床中(zhong)(zhong)。閥(fa)(fa)(fa)用電(dian)(dian)磁(ci)鐵(tie)不設復(fu)位裝置，而由閥(fa)(fa)(fa)體(ti)(ti)中(zhong)(zhong)的彈簧(huang)(huang)使之(zhi)復(fu)位。當電(dian)(dian)磁(ci)鐵(tie)的勵(li)磁(ci)繞(rao)組通過(guo)電(dian)(dian)流時，電(dian)(dian)磁(ci)吸力(li)即克服(fu)彈簧(huang)(huang)阻(zu)力(li)，使閥(fa)(fa)(fa)體(ti)(ti)的推桿移(yi)動(dong)(dong)，將閥(fa)(fa)(fa)門開啟;當勵(li)磁(ci)繞(rao)組斷電(dian)(dian)后，在(zai)復(fu)位彈簧(huang)(huang)作(zuo)(zuo)用下，閥(fa)(fa)(fa)體(ti)(ti)推桿便推動(dong)(dong)銜鐵(tie)，使其移(yi)動(dong)(dong)額定行程處，閥(fa)(fa)(fa)門關(guan)閉。閥(fa)(fa)(fa)用電(dian)(dian)磁(ci)鐵(tie)分(fen)為(wei)濕式(shi)和干式(shi)兩種。濕式(shi)閥(fa)(fa)(fa)用電(dian)(dian)磁(ci)鐵(tie)的銜鐵(tie)在(zai)液壓油中(zhong)(zhong)工作(zuo)(zuo)，由于(yu)油的冷卻(que)作(zuo)(zuo)用，使其與具有相同吸力(li)的電(dian)(dian)磁(ci)鐵(tie)相比，有較小的尺寸。

電磁鐵的應用

門(men)禁(jin)：為什(shen)么門(men)禁(jin)可以在沒刷(shua)卡(ka)(ka)時(shi)把(ba)門(men)牢(lao)牢(lao)的(de)“抓住”？原來單(dan)元門(men)是由(you)鋼(gang)材料做成的(de)，那(nei)個(ge)金屬(shu)體(ti)在通電時(shi)可以產(chan)(chan)生強大的(de)磁(ci)(ci)場，產(chan)(chan)生的(de)磁(ci)(ci)力能(neng)把(ba)門(men)牢(lao)牢(lao)的(de)吸住，而刷(shua)卡(ka)(ka)的(de)瞬間，切斷電流，金屬(shu)體(ti)失去(qu)磁(ci)(ci)性(xing)，我(wo)們(men)就可以打開(kai)門(men)了。那(nei)個(ge)金屬(shu)體(ti)其實是一(yi)塊電磁(ci)(ci)鐵。

電(dian)(dian)(dian)磁(ci)起(qi)(qi)重(zhong)(zhong)機(ji)：最直接的應用之(zhi)一是電(dian)(dian)(dian)磁(ci)起(qi)(qi)重(zhong)(zhong)機(ji)。電(dian)(dian)(dian)磁(ci)鐵(tie)安(an)裝在吊車上，通電(dian)(dian)(dian)后吸起(qi)(qi)大量鋼(gang)鐵(tie)，移動到另一個(ge)位置后切斷電(dian)(dian)(dian)流，鋼(gang)鐵(tie)被放下，免去了(le)打捆的麻煩。大型(xing)電(dian)(dian)(dian)磁(ci)起(qi)(qi)重(zhong)(zhong)機(ji)一次可以(yi)吊起(qi)(qi)幾噸鋼(gang)材。

在電(dian)(dian)(dian)動(dong)機(ji)、發(fa)電(dian)(dian)(dian)機(ji)、電(dian)(dian)(dian)鈴和電(dian)(dian)(dian)磁(ci)繼電(dian)(dian)(dian)器里也用(yong)到電(dian)(dian)(dian)磁(ci)鐵。全自動(dong)洗衣機(ji)的(de)進(jin)水(shui)、排水(shui)閥(fa)(fa)門，衛生間里感應式沖水(shui)器的(de)閥(fa)(fa)門，也都是由電(dian)(dian)(dian)磁(ci)鐵控制的(de)。

電磁鐵的另一個應用是產生強磁場。現(xian)代技術中很多地(di)方(fang)需(xu)要的強磁場都(dou)由電磁鐵提(ti)供，如大型電動(dong)機、發電機、磁療設備等(deng)。