電(dian)(dian)磁(ci)(ci)閥(fa)(fa)（Electromagnetic valve）是(shi)用(yong)電(dian)(dian)磁(ci)(ci)控(kong)(kong)(kong)(kong)制(zhi)的(de)(de)(de)工(gong)業(ye)設備，是(shi)用(yong)來控(kong)(kong)(kong)(kong)制(zhi)流(liu)體(ti)的(de)(de)(de)自動(dong)化基礎(chu)元件，屬于執行器，并(bing)不限于液壓、氣動(dong)。用(yong)在(zai)工(gong)業(ye)控(kong)(kong)(kong)(kong)制(zhi)系(xi)統中調(diao)整介質(zhi)的(de)(de)(de)方(fang)向(xiang)(xiang)、流(liu)量、速度(du)和(he)其他的(de)(de)(de)參(can)數(shu)。電(dian)(dian)磁(ci)(ci)閥(fa)(fa)可以(yi)配(pei)合不同的(de)(de)(de)電(dian)(dian)路來實現預期的(de)(de)(de)控(kong)(kong)(kong)(kong)制(zhi)，而控(kong)(kong)(kong)(kong)制(zhi)的(de)(de)(de)精度(du)和(he)靈活性(xing)都能夠保證。電(dian)(dian)磁(ci)(ci)閥(fa)(fa)有(you)很多種，不同的(de)(de)(de)電(dian)(dian)磁(ci)(ci)閥(fa)(fa)在(zai)控(kong)(kong)(kong)(kong)制(zhi)系(xi)統的(de)(de)(de)不同位置發揮作用(yong)，最常用(yong)的(de)(de)(de)是(shi)單向(xiang)(xiang)閥(fa)(fa)、安(an)全閥(fa)(fa)、方(fang)向(xiang)(xiang)控(kong)(kong)(kong)(kong)制(zhi)閥(fa)(fa)、速度(du)調(diao)節閥(fa)(fa)等(deng)。

電(dian)磁(ci)(ci)閥里有(you)密(mi)閉的(de)(de)腔，在不(bu)(bu)(bu)同(tong)(tong)位置(zhi)開(kai)有(you)通(tong)孔，每個孔連接不(bu)(bu)(bu)同(tong)(tong)的(de)(de)油(you)(you)管，腔中間是(shi)活(huo)塞(sai)(sai)，兩(liang)面(mian)是(shi)兩(liang)塊電(dian)磁(ci)(ci)鐵，哪(na)面(mian)的(de)(de)磁(ci)(ci)鐵線圈(quan)通(tong)電(dian)閥體就會被吸引到哪(na)邊，通(tong)過控(kong)制(zhi)(zhi)閥體的(de)(de)移(yi)動(dong)(dong)(dong)來開(kai)啟(qi)或關閉不(bu)(bu)(bu)同(tong)(tong)的(de)(de)排油(you)(you)孔，而進油(you)(you)孔是(shi)常(chang)開(kai)的(de)(de)，液壓油(you)(you)就會進入(ru)不(bu)(bu)(bu)同(tong)(tong)的(de)(de)排油(you)(you)管，然(ran)后(hou)通(tong)過油(you)(you)的(de)(de)壓力來推動(dong)(dong)(dong)油(you)(you)缸(gang)的(de)(de)活(huo)塞(sai)(sai)，活(huo)塞(sai)(sai)又帶動(dong)(dong)(dong)活(huo)塞(sai)(sai)桿，活(huo)塞(sai)(sai)桿帶動(dong)(dong)(dong)機械裝置(zhi)。這(zhe)樣通(tong)過控(kong)制(zhi)(zhi)電(dian)磁(ci)(ci)鐵的(de)(de)電(dian)流通(tong)斷就控(kong)制(zhi)(zhi)了機械運動(dong)(dong)(dong)。

1、電磁閥從(cong)原理上分為三大類：

直動(dong)式電(dian)磁閥

原理：通(tong)電時，電磁(ci)線圈(quan)產生電磁(ci)力把(ba)關(guan)閉件從閥座上提(ti)起，閥門打開；斷電時，電磁(ci)力消失(shi)，彈簧(huang)把(ba)關(guan)閉件壓(ya)在閥座上，閥門關(guan)閉。

特點(dian)：在(zai)真空、負(fu)壓、零壓時能正(zheng)常工作(zuo)，但通徑一般(ban)不超過25mm。

分步直(zhi)動式電磁閥

原(yuan)理：它(ta)是(shi)一種直(zhi)(zhi)動(dong)(dong)(dong)和先導(dao)式相(xiang)結合的原(yuan)理，當入口(kou)與出口(kou)沒有(you)壓(ya)差時，通(tong)電后，電磁(ci)力直(zhi)(zhi)接把先導(dao)小閥(fa)和主閥(fa)關(guan)閉(bi)件(jian)依次向上(shang)提起，閥(fa)門(men)打開。當入口(kou)與出口(kou)達到啟動(dong)(dong)(dong)壓(ya)差時，通(tong)電后，電磁(ci)力先導(dao)小閥(fa)，主閥(fa)下腔壓(ya)力上(shang)升(sheng)，上(shang)腔壓(ya)力下降，從而利用(yong)壓(ya)差把主閥(fa)向上(shang)推開；斷電時，先導(dao)閥(fa)利用(yong)彈簧力或介質壓(ya)力推動(dong)(dong)(dong)關(guan)閉(bi)件(jian)，向下移動(dong)(dong)(dong)，使閥(fa)門(men)關(guan)閉(bi)。

特點：在(zai)零壓(ya)差或真空、高壓(ya)時亦能可(ke)*動作(zuo)，但功率較大，要求必須水平安裝。

先導(dao)式電磁閥

原理(li)：通電(dian)時，電(dian)磁力(li)(li)把先導孔打(da)開(kai)，上腔(qiang)室壓(ya)(ya)力(li)(li)迅速下(xia)降，在關 閉件(jian)(jian)周(zhou)圍形成(cheng)(cheng)上低(di)(di)下(xia)高(gao)的壓(ya)(ya)差，流體壓(ya)(ya)力(li)(li)推(tui)動關閉件(jian)(jian)向上移動，閥(fa)門打(da)開(kai)；斷(duan)電(dian)時，彈簧(huang)力(li)(li)把先導孔關閉，入(ru)口壓(ya)(ya)力(li)(li)通過旁通孔迅速腔(qiang)室在關閥(fa)件(jian)(jian)周(zhou)圍形成(cheng)(cheng)下(xia)低(di)(di)上高(gao)的壓(ya)(ya)差，流體壓(ya)(ya)力(li)(li)推(tui)動關閉件(jian)(jian)向下(xia)移動，關閉閥(fa)門。

特點：流(liu)體壓力范圍上(shang)限較(jiao)高，可任意安裝（需定制(zhi)）但必須滿足(zu)流(liu)體壓差條件(jian)。

2、電磁(ci)閥從閥結(jie)構(gou)(gou)和材料上(shang)的(de)不(bu)同與原理(li)上(shang)的(de)區別，分(fen)(fen)為六個分(fen)(fen)支小(xiao)類：直動(dong)膜(mo)片結(jie)構(gou)(gou)、分(fen)(fen)步直動(dong)膜(mo)片結(jie)構(gou)(gou)、先(xian)導膜(mo)片結(jie)構(gou)(gou)、直動(dong)活塞結(jie)構(gou)(gou)、分(fen)(fen)步直動(dong)活塞結(jie)構(gou)(gou)、先(xian)導活塞結(jie)構(gou)(gou)。

3、電(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)閥(fa)(fa)(fa)按照功能(neng)分類：水(shui)用電(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)閥(fa)(fa)(fa)、蒸(zheng)汽電(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)閥(fa)(fa)(fa)、制冷電(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)閥(fa)(fa)(fa)、低溫電(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)閥(fa)(fa)(fa)、燃氣(qi)電(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)閥(fa)(fa)(fa)、消防電(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)閥(fa)(fa)(fa)、氨用電(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)閥(fa)(fa)(fa)、氣(qi)體(ti)(ti)電(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)閥(fa)(fa)(fa)、液(ye)體(ti)(ti)電(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)閥(fa)(fa)(fa)、微(wei)型電(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)閥(fa)(fa)(fa)、脈沖電(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)閥(fa)(fa)(fa)、液(ye)壓電(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)閥(fa)(fa)(fa) 常開電(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)閥(fa)(fa)(fa)、油用電(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)閥(fa)(fa)(fa)、直流電(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)閥(fa)(fa)(fa)、高壓電(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)閥(fa)(fa)(fa)、防爆(bao)電(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)閥(fa)(fa)(fa)等(deng)。