電(dian)磁(ci)(ci)閥(fa)(fa)（Electromagnetic valve）是用(yong)電(dian)磁(ci)(ci)控(kong)(kong)制的(de)(de)工業設備(bei)，是用(yong)來控(kong)(kong)制流體的(de)(de)自動(dong)化基礎元件，屬于(yu)執(zhi)行器，并(bing)不(bu)(bu)限于(yu)液(ye)壓、氣動(dong)。用(yong)在工業控(kong)(kong)制系(xi)統(tong)中(zhong)調整介質的(de)(de)方向、流量、速度和(he)其他的(de)(de)參數。電(dian)磁(ci)(ci)閥(fa)(fa)可以配合不(bu)(bu)同(tong)的(de)(de)電(dian)路(lu)來實(shi)現預(yu)期的(de)(de)控(kong)(kong)制，而控(kong)(kong)制的(de)(de)精度和(he)靈活性都能(neng)夠保(bao)證。電(dian)磁(ci)(ci)閥(fa)(fa)有很多(duo)種(zhong)，不(bu)(bu)同(tong)的(de)(de)電(dian)磁(ci)(ci)閥(fa)(fa)在控(kong)(kong)制系(xi)統(tong)的(de)(de)不(bu)(bu)同(tong)位置發揮作用(yong)，最常用(yong)的(de)(de)是單(dan)向閥(fa)(fa)、安全(quan)閥(fa)(fa)、方向控(kong)(kong)制閥(fa)(fa)、速度調節閥(fa)(fa)等。

電(dian)磁(ci)閥里有密閉(bi)的(de)(de)腔，在不(bu)(bu)同(tong)位置開(kai)有通孔，每個(ge)孔連接不(bu)(bu)同(tong)的(de)(de)油管，腔中間是(shi)活(huo)塞(sai)(sai)，兩(liang)面是(shi)兩(liang)塊電(dian)磁(ci)鐵(tie)，哪面的(de)(de)磁(ci)鐵(tie)線圈通電(dian)閥體就會被吸引(yin)到哪邊(bian)，通過控(kong)制(zhi)閥體的(de)(de)移動(dong)來開(kai)啟或關閉(bi)不(bu)(bu)同(tong)的(de)(de)排油孔，而進油孔是(shi)常開(kai)的(de)(de)，液壓(ya)油就會進入不(bu)(bu)同(tong)的(de)(de)排油管，然后通過油的(de)(de)壓(ya)力來推動(dong)油缸的(de)(de)活(huo)塞(sai)(sai)，活(huo)塞(sai)(sai)又帶動(dong)活(huo)塞(sai)(sai)桿(gan)(gan)，活(huo)塞(sai)(sai)桿(gan)(gan)帶動(dong)機械(xie)裝(zhuang)置。這樣通過控(kong)制(zhi)電(dian)磁(ci)鐵(tie)的(de)(de)電(dian)流(liu)通斷就控(kong)制(zhi)了機械(xie)運動(dong)。

1、電(dian)磁閥從原理上分為(wei)三大(da)類(lei)：

直動式電磁閥

原理：通(tong)電(dian)時，電(dian)磁線圈(quan)產生(sheng)電(dian)磁力(li)把關(guan)(guan)閉件(jian)從閥(fa)座上(shang)提(ti)起，閥(fa)門(men)打(da)開(kai)；斷電(dian)時，電(dian)磁力(li)消失，彈簧把關(guan)(guan)閉件(jian)壓在閥(fa)座上(shang)，閥(fa)門(men)關(guan)(guan)閉。

特點：在真空、負壓、零壓時(shi)能正常工作，但通徑一般不(bu)超過25mm。

分步(bu)直動(dong)式電(dian)磁(ci)閥

原(yuan)理(li)：它是一種直動(dong)和先(xian)導(dao)(dao)式相(xiang)結合的原(yuan)理(li)，當入(ru)口與出口沒有壓(ya)差時(shi)，通電(dian)(dian)(dian)后(hou)，電(dian)(dian)(dian)磁力直接把(ba)先(xian)導(dao)(dao)小閥(fa)(fa)(fa)和主閥(fa)(fa)(fa)關(guan)閉(bi)件依次向(xiang)上(shang)提起，閥(fa)(fa)(fa)門打(da)開。當入(ru)口與出口達(da)到啟動(dong)壓(ya)差時(shi)，通電(dian)(dian)(dian)后(hou)，電(dian)(dian)(dian)磁力先(xian)導(dao)(dao)小閥(fa)(fa)(fa)，主閥(fa)(fa)(fa)下(xia)腔(qiang)壓(ya)力上(shang)升，上(shang)腔(qiang)壓(ya)力下(xia)降，從(cong)而利用壓(ya)差把(ba)主閥(fa)(fa)(fa)向(xiang)上(shang)推開；斷(duan)電(dian)(dian)(dian)時(shi)，先(xian)導(dao)(dao)閥(fa)(fa)(fa)利用彈簧力或(huo)介質壓(ya)力推動(dong)關(guan)閉(bi)件，向(xiang)下(xia)移動(dong)，使閥(fa)(fa)(fa)門關(guan)閉(bi)。

特點：在零壓(ya)差或真(zhen)空(kong)、高壓(ya)時亦能(neng)可*動作，但功(gong)率較大，要求必須水(shui)平安裝。

先導式電磁(ci)閥

原理(li)：通電(dian)時(shi)，電(dian)磁(ci)力(li)(li)(li)(li)(li)把先(xian)導(dao)孔(kong)打開，上腔室壓(ya)(ya)力(li)(li)(li)(li)(li)迅速(su)下(xia)降，在(zai)關(guan) 閉件周圍形成上低(di)下(xia)高(gao)的壓(ya)(ya)差，流(liu)體(ti)壓(ya)(ya)力(li)(li)(li)(li)(li)推動關(guan)閉件向上移(yi)動，閥(fa)(fa)門打開；斷(duan)電(dian)時(shi)，彈(dan)簧力(li)(li)(li)(li)(li)把先(xian)導(dao)孔(kong)關(guan)閉，入口壓(ya)(ya)力(li)(li)(li)(li)(li)通過旁通孔(kong)迅速(su)腔室在(zai)關(guan)閥(fa)(fa)件周圍形成下(xia)低(di)上高(gao)的壓(ya)(ya)差，流(liu)體(ti)壓(ya)(ya)力(li)(li)(li)(li)(li)推動關(guan)閉件向下(xia)移(yi)動，關(guan)閉閥(fa)(fa)門。

特(te)點(dian)：流體壓力范圍上限較高，可(ke)任意(yi)安裝（需(xu)定制(zhi)）但必須(xu)滿足(zu)流體壓差條件(jian)。

2、電磁閥從閥結(jie)構(gou)和材料上的不(bu)同與原理上的區(qu)別，分(fen)為六(liu)個分(fen)支小類：直(zhi)動膜片結(jie)構(gou)、分(fen)步直(zhi)動膜片結(jie)構(gou)、先(xian)導膜片結(jie)構(gou)、直(zhi)動活(huo)塞結(jie)構(gou)、分(fen)步直(zhi)動活(huo)塞結(jie)構(gou)、先(xian)導活(huo)塞結(jie)構(gou)。

3、電(dian)(dian)(dian)(dian)磁(ci)閥(fa)按照(zhao)功能分類(lei)：水用電(dian)(dian)(dian)(dian)磁(ci)閥(fa)、蒸汽電(dian)(dian)(dian)(dian)磁(ci)閥(fa)、制(zhi)冷(leng)電(dian)(dian)(dian)(dian)磁(ci)閥(fa)、低溫電(dian)(dian)(dian)(dian)磁(ci)閥(fa)、燃氣電(dian)(dian)(dian)(dian)磁(ci)閥(fa)、消防電(dian)(dian)(dian)(dian)磁(ci)閥(fa)、氨用電(dian)(dian)(dian)(dian)磁(ci)閥(fa)、氣體電(dian)(dian)(dian)(dian)磁(ci)閥(fa)、液體電(dian)(dian)(dian)(dian)磁(ci)閥(fa)、微(wei)(wei)型(xing)電(dian)(dian)(dian)(dian)磁(ci)閥(fa)、脈(mo)沖(chong)電(dian)(dian)(dian)(dian)磁(ci)閥(fa)、液壓(ya)電(dian)(dian)(dian)(dian)磁(ci)閥(fa) 常(chang)開電(dian)(dian)(dian)(dian)磁(ci)閥(fa)、油用電(dian)(dian)(dian)(dian)磁(ci)閥(fa)、直流電(dian)(dian)(dian)(dian)磁(ci)閥(fa)、高壓(ya)電(dian)(dian)(dian)(dian)磁(ci)閥(fa)、防爆(bao)電(dian)(dian)(dian)(dian)磁(ci)閥(fa)等。