電(dian)(dian)磁(ci)(ci)閥(fa)(fa)(fa)(fa)(fa)（Electromagnetic valve）是(shi)用電(dian)(dian)磁(ci)(ci)控(kong)制(zhi)的(de)(de)(de)工(gong)業(ye)(ye)設備，是(shi)用來控(kong)制(zhi)流體的(de)(de)(de)自動化基礎元件，屬(shu)于執行(xing)器，并不(bu)限于液壓(ya)、氣動。用在(zai)工(gong)業(ye)(ye)控(kong)制(zhi)系統(tong)中調(diao)(diao)整介質(zhi)的(de)(de)(de)方向(xiang)、流量、速(su)(su)度(du)和(he)其他的(de)(de)(de)參數。電(dian)(dian)磁(ci)(ci)閥(fa)(fa)(fa)(fa)(fa)可以配合不(bu)同(tong)的(de)(de)(de)電(dian)(dian)路來實(shi)現(xian)預(yu)期的(de)(de)(de)控(kong)制(zhi)，而控(kong)制(zhi)的(de)(de)(de)精度(du)和(he)靈(ling)活性都(dou)能夠保證(zheng)。電(dian)(dian)磁(ci)(ci)閥(fa)(fa)(fa)(fa)(fa)有很多種，不(bu)同(tong)的(de)(de)(de)電(dian)(dian)磁(ci)(ci)閥(fa)(fa)(fa)(fa)(fa)在(zai)控(kong)制(zhi)系統(tong)的(de)(de)(de)不(bu)同(tong)位置發揮作用，最常用的(de)(de)(de)是(shi)單(dan)向(xiang)閥(fa)(fa)(fa)(fa)(fa)、安全閥(fa)(fa)(fa)(fa)(fa)、方向(xiang)控(kong)制(zhi)閥(fa)(fa)(fa)(fa)(fa)、速(su)(su)度(du)調(diao)(diao)節閥(fa)(fa)(fa)(fa)(fa)等。

電(dian)(dian)磁(ci)(ci)閥(fa)(fa)里有密閉(bi)的(de)(de)(de)(de)(de)腔，在不(bu)(bu)同(tong)(tong)位(wei)置開(kai)有通(tong)(tong)(tong)孔(kong)，每個孔(kong)連接不(bu)(bu)同(tong)(tong)的(de)(de)(de)(de)(de)油管，腔中(zhong)間是活塞，兩面是兩塊電(dian)(dian)磁(ci)(ci)鐵，哪面的(de)(de)(de)(de)(de)磁(ci)(ci)鐵線圈通(tong)(tong)(tong)電(dian)(dian)閥(fa)(fa)體就(jiu)(jiu)會被吸引(yin)到哪邊，通(tong)(tong)(tong)過控(kong)制(zhi)閥(fa)(fa)體的(de)(de)(de)(de)(de)移(yi)動(dong)來(lai)開(kai)啟或關閉(bi)不(bu)(bu)同(tong)(tong)的(de)(de)(de)(de)(de)排(pai)油孔(kong)，而進(jin)油孔(kong)是常開(kai)的(de)(de)(de)(de)(de)，液(ye)壓油就(jiu)(jiu)會進(jin)入(ru)不(bu)(bu)同(tong)(tong)的(de)(de)(de)(de)(de)排(pai)油管，然后通(tong)(tong)(tong)過油的(de)(de)(de)(de)(de)壓力來(lai)推(tui)動(dong)油缸的(de)(de)(de)(de)(de)活塞，活塞又帶動(dong)活塞桿，活塞桿帶動(dong)機械裝置。這樣通(tong)(tong)(tong)過控(kong)制(zhi)電(dian)(dian)磁(ci)(ci)鐵的(de)(de)(de)(de)(de)電(dian)(dian)流通(tong)(tong)(tong)斷(duan)就(jiu)(jiu)控(kong)制(zhi)了機械運動(dong)。

1、電磁閥從原理上(shang)分為三大類：

直動式電磁閥

原理：通電(dian)時，電(dian)磁線(xian)圈(quan)產生電(dian)磁力把關(guan)閉(bi)件(jian)(jian)從(cong)閥座(zuo)上提起，閥門打開；斷電(dian)時，電(dian)磁力消失，彈簧把關(guan)閉(bi)件(jian)(jian)壓在閥座(zuo)上，閥門關(guan)閉(bi)。

特點：在真空、負壓、零壓時(shi)能(neng)正常工作(zuo)，但通(tong)徑一般(ban)不超過25mm。

分(fen)步直(zhi)動式電磁閥

原(yuan)理：它是一種直動(dong)(dong)和先(xian)導(dao)式相結合的原(yuan)理，當入(ru)口(kou)與出口(kou)沒有壓(ya)差時(shi)，通電(dian)后，電(dian)磁力(li)(li)直接把先(xian)導(dao)小閥(fa)(fa)和主閥(fa)(fa)關閉件(jian)依次向(xiang)(xiang)上提起，閥(fa)(fa)門打開。當入(ru)口(kou)與出口(kou)達到(dao)啟(qi)動(dong)(dong)壓(ya)差時(shi)，通電(dian)后，電(dian)磁力(li)(li)先(xian)導(dao)小閥(fa)(fa)，主閥(fa)(fa)下(xia)腔(qiang)壓(ya)力(li)(li)上升，上腔(qiang)壓(ya)力(li)(li)下(xia)降，從而利(li)用壓(ya)差把主閥(fa)(fa)向(xiang)(xiang)上推開；斷(duan)電(dian)時(shi)，先(xian)導(dao)閥(fa)(fa)利(li)用彈簧力(li)(li)或介質壓(ya)力(li)(li)推動(dong)(dong)關閉件(jian)，向(xiang)(xiang)下(xia)移動(dong)(dong)，使閥(fa)(fa)門關閉。

特點：在零壓差或(huo)真空、高壓時亦(yi)能(neng)可*動作，但功率較大，要求必須水(shui)平安裝。

先導式電磁閥

原理(li)：通(tong)電(dian)(dian)時，電(dian)(dian)磁力(li)把先導(dao)孔(kong)打(da)開，上腔室壓(ya)(ya)力(li)迅速下(xia)降，在關(guan)(guan) 閉(bi)件周圍(wei)形成上低(di)下(xia)高(gao)的(de)(de)壓(ya)(ya)差，流(liu)體壓(ya)(ya)力(li)推動關(guan)(guan)閉(bi)件向上移動，閥門打(da)開；斷電(dian)(dian)時，彈簧力(li)把先導(dao)孔(kong)關(guan)(guan)閉(bi)，入口壓(ya)(ya)力(li)通(tong)過旁(pang)通(tong)孔(kong)迅速腔室在關(guan)(guan)閥件周圍(wei)形成下(xia)低(di)上高(gao)的(de)(de)壓(ya)(ya)差，流(liu)體壓(ya)(ya)力(li)推動關(guan)(guan)閉(bi)件向下(xia)移動，關(guan)(guan)閉(bi)閥門。

特點：流體壓(ya)力(li)范圍上限較(jiao)高(gao)，可(ke)任意(yi)安(an)裝(zhuang)（需定制）但必須滿(man)足流體壓(ya)差條件。

2、電磁(ci)閥(fa)從閥(fa)結構(gou)(gou)和材料上的(de)不同與原理上的(de)區別，分(fen)為六個分(fen)支小類(lei)：直(zhi)動膜片結構(gou)(gou)、分(fen)步直(zhi)動膜片結構(gou)(gou)、先(xian)導(dao)膜片結構(gou)(gou)、直(zhi)動活(huo)塞(sai)結構(gou)(gou)、分(fen)步直(zhi)動活(huo)塞(sai)結構(gou)(gou)、先(xian)導(dao)活(huo)塞(sai)結構(gou)(gou)。

3、電(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)(ci)閥(fa)(fa)(fa)(fa)按照功能分類：水用(yong)電(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)(ci)閥(fa)(fa)(fa)(fa)、蒸汽(qi)電(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)(ci)閥(fa)(fa)(fa)(fa)、制(zhi)冷電(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)(ci)閥(fa)(fa)(fa)(fa)、低(di)溫電(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)(ci)閥(fa)(fa)(fa)(fa)、燃氣電(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)(ci)閥(fa)(fa)(fa)(fa)、消(xiao)防(fang)電(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)(ci)閥(fa)(fa)(fa)(fa)、氨用(yong)電(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)(ci)閥(fa)(fa)(fa)(fa)、氣體電(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)(ci)閥(fa)(fa)(fa)(fa)、液體電(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)(ci)閥(fa)(fa)(fa)(fa)、微型電(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)(ci)閥(fa)(fa)(fa)(fa)、脈沖電(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)(ci)閥(fa)(fa)(fa)(fa)、液壓(ya)電(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)(ci)閥(fa)(fa)(fa)(fa) 常開(kai)電(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)(ci)閥(fa)(fa)(fa)(fa)、油用(yong)電(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)(ci)閥(fa)(fa)(fa)(fa)、直流電(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)(ci)閥(fa)(fa)(fa)(fa)、高(gao)壓(ya)電(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)(ci)閥(fa)(fa)(fa)(fa)、防(fang)爆(bao)電(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)(ci)閥(fa)(fa)(fa)(fa)等(deng)。