電(dian)(dian)(dian)磁閥（Electromagnetic valve）是(shi)用(yong)電(dian)(dian)(dian)磁控(kong)(kong)制(zhi)的(de)工(gong)業設備，是(shi)用(yong)來控(kong)(kong)制(zhi)流體(ti)的(de)自動(dong)化基礎(chu)元件(jian)，屬于執行器，并不(bu)限于液壓、氣動(dong)。用(yong)在工(gong)業控(kong)(kong)制(zhi)系統中調整介質的(de)方向(xiang)(xiang)、流量、速度(du)和(he)其他的(de)參數。電(dian)(dian)(dian)磁閥可以配合不(bu)同(tong)(tong)的(de)電(dian)(dian)(dian)路來實(shi)現預期的(de)控(kong)(kong)制(zhi)，而控(kong)(kong)制(zhi)的(de)精(jing)度(du)和(he)靈活性都能夠保證。電(dian)(dian)(dian)磁閥有(you)很多種(zhong)，不(bu)同(tong)(tong)的(de)電(dian)(dian)(dian)磁閥在控(kong)(kong)制(zhi)系統的(de)不(bu)同(tong)(tong)位置發(fa)揮作用(yong)，最(zui)常用(yong)的(de)是(shi)單向(xiang)(xiang)閥、安(an)全(quan)閥、方向(xiang)(xiang)控(kong)(kong)制(zhi)閥、速度(du)調節閥等。

電磁(ci)(ci)閥里有(you)密閉的(de)(de)腔(qiang)，在不(bu)(bu)同(tong)位置(zhi)開(kai)(kai)(kai)有(you)通(tong)孔，每(mei)個(ge)孔連接(jie)不(bu)(bu)同(tong)的(de)(de)油(you)管，腔(qiang)中間是活塞，兩面(mian)是兩塊電磁(ci)(ci)鐵，哪面(mian)的(de)(de)磁(ci)(ci)鐵線圈通(tong)電閥體(ti)就會被吸引到哪邊，通(tong)過(guo)(guo)控(kong)制閥體(ti)的(de)(de)移動來開(kai)(kai)(kai)啟或關閉不(bu)(bu)同(tong)的(de)(de)排(pai)油(you)孔，而進(jin)油(you)孔是常開(kai)(kai)(kai)的(de)(de)，液壓(ya)油(you)就會進(jin)入不(bu)(bu)同(tong)的(de)(de)排(pai)油(you)管，然后通(tong)過(guo)(guo)油(you)的(de)(de)壓(ya)力來推動油(you)缸的(de)(de)活塞，活塞又帶(dai)動活塞桿，活塞桿帶(dai)動機械裝(zhuang)置(zhi)。這樣通(tong)過(guo)(guo)控(kong)制電磁(ci)(ci)鐵的(de)(de)電流通(tong)斷就控(kong)制了機械運(yun)動。

1、電磁閥從原(yuan)理(li)上(shang)分(fen)為三大類(lei)：

直動式電磁閥

原理：通(tong)電(dian)時(shi)，電(dian)磁線圈(quan)產生電(dian)磁力(li)把(ba)關閉件從閥座(zuo)上(shang)提起(qi)，閥門(men)打開；斷(duan)電(dian)時(shi)，電(dian)磁力(li)消失，彈簧把(ba)關閉件壓(ya)在閥座(zuo)上(shang)，閥門(men)關閉。

特點：在真空(kong)、負壓(ya)、零壓(ya)時能正常工作，但通徑(jing)一般不(bu)超過25mm。

分步直動式(shi)電磁閥

原理：它是(shi)一種直動(dong)和(he)先導式相結合的原理，當入(ru)口(kou)(kou)與出(chu)口(kou)(kou)沒有壓(ya)(ya)(ya)差時(shi)(shi)，通(tong)電(dian)(dian)后，電(dian)(dian)磁力(li)直接把先導小(xiao)閥(fa)和(he)主閥(fa)關(guan)閉(bi)件依次向上(shang)提起，閥(fa)門打開。當入(ru)口(kou)(kou)與出(chu)口(kou)(kou)達(da)到啟動(dong)壓(ya)(ya)(ya)差時(shi)(shi)，通(tong)電(dian)(dian)后，電(dian)(dian)磁力(li)先導小(xiao)閥(fa)，主閥(fa)下腔壓(ya)(ya)(ya)力(li)上(shang)升，上(shang)腔壓(ya)(ya)(ya)力(li)下降，從而利用(yong)壓(ya)(ya)(ya)差把主閥(fa)向上(shang)推開；斷(duan)電(dian)(dian)時(shi)(shi)，先導閥(fa)利用(yong)彈簧力(li)或介質壓(ya)(ya)(ya)力(li)推動(dong)關(guan)閉(bi)件，向下移動(dong)，使閥(fa)門關(guan)閉(bi)。

特點(dian)：在零壓差或真空、高壓時亦能可*動作，但功率較大，要求必須水平(ping)安裝。

先導式電磁(ci)閥(fa)

原(yuan)理：通(tong)電(dian)時，電(dian)磁(ci)力(li)(li)把先(xian)導孔(kong)(kong)(kong)打(da)開(kai)，上腔室(shi)壓力(li)(li)迅(xun)速下(xia)降，在關 閉件(jian)周(zhou)(zhou)圍形成上低(di)下(xia)高的壓差，流體壓力(li)(li)推動關閉件(jian)向(xiang)上移(yi)動，閥門打(da)開(kai)；斷電(dian)時，彈簧(huang)力(li)(li)把先(xian)導孔(kong)(kong)(kong)關閉，入口(kou)壓力(li)(li)通(tong)過旁通(tong)孔(kong)(kong)(kong)迅(xun)速腔室(shi)在關閥件(jian)周(zhou)(zhou)圍形成下(xia)低(di)上高的壓差，流體壓力(li)(li)推動關閉件(jian)向(xiang)下(xia)移(yi)動，關閉閥門。

特點：流(liu)體(ti)壓(ya)力范(fan)圍(wei)上限較(jiao)高(gao)，可任意安裝（需定制）但必須滿足流(liu)體(ti)壓(ya)差(cha)條件。

2、電磁閥(fa)(fa)從閥(fa)(fa)結(jie)(jie)(jie)(jie)(jie)構(gou)(gou)和材料(liao)上的不同與原(yuan)理上的區別(bie)，分(fen)為六個分(fen)支小類(lei)：直動膜(mo)片結(jie)(jie)(jie)(jie)(jie)構(gou)(gou)、分(fen)步(bu)直動膜(mo)片結(jie)(jie)(jie)(jie)(jie)構(gou)(gou)、先(xian)導膜(mo)片結(jie)(jie)(jie)(jie)(jie)構(gou)(gou)、直動活塞(sai)結(jie)(jie)(jie)(jie)(jie)構(gou)(gou)、分(fen)步(bu)直動活塞(sai)結(jie)(jie)(jie)(jie)(jie)構(gou)(gou)、先(xian)導活塞(sai)結(jie)(jie)(jie)(jie)(jie)構(gou)(gou)。

3、電(dian)(dian)(dian)(dian)(dian)磁(ci)(ci)閥(fa)按照功能分類(lei)：水用電(dian)(dian)(dian)(dian)(dian)磁(ci)(ci)閥(fa)、蒸汽電(dian)(dian)(dian)(dian)(dian)磁(ci)(ci)閥(fa)、制冷電(dian)(dian)(dian)(dian)(dian)磁(ci)(ci)閥(fa)、低溫電(dian)(dian)(dian)(dian)(dian)磁(ci)(ci)閥(fa)、燃(ran)氣(qi)電(dian)(dian)(dian)(dian)(dian)磁(ci)(ci)閥(fa)、消防電(dian)(dian)(dian)(dian)(dian)磁(ci)(ci)閥(fa)、氨(an)用電(dian)(dian)(dian)(dian)(dian)磁(ci)(ci)閥(fa)、氣(qi)體電(dian)(dian)(dian)(dian)(dian)磁(ci)(ci)閥(fa)、液體電(dian)(dian)(dian)(dian)(dian)磁(ci)(ci)閥(fa)、微型電(dian)(dian)(dian)(dian)(dian)磁(ci)(ci)閥(fa)、脈沖電(dian)(dian)(dian)(dian)(dian)磁(ci)(ci)閥(fa)、液壓(ya)電(dian)(dian)(dian)(dian)(dian)磁(ci)(ci)閥(fa) 常開電(dian)(dian)(dian)(dian)(dian)磁(ci)(ci)閥(fa)、油用電(dian)(dian)(dian)(dian)(dian)磁(ci)(ci)閥(fa)、直流電(dian)(dian)(dian)(dian)(dian)磁(ci)(ci)閥(fa)、高壓(ya)電(dian)(dian)(dian)(dian)(dian)磁(ci)(ci)閥(fa)、防爆電(dian)(dian)(dian)(dian)(dian)磁(ci)(ci)閥(fa)等(deng)。