電(dian)(dian)磁(ci)閥(fa)(fa)（Electromagnetic valve）是用(yong)(yong)電(dian)(dian)磁(ci)控制(zhi)的(de)工業設(she)備(bei)，是用(yong)(yong)來控制(zhi)流(liu)體的(de)自(zi)動化基礎元件，屬于執行器，并不限于液壓(ya)、氣動。用(yong)(yong)在工業控制(zhi)系(xi)統中(zhong)調整介質的(de)方向(xiang)、流(liu)量、速度和其他的(de)參數。電(dian)(dian)磁(ci)閥(fa)(fa)可以配(pei)合不同(tong)的(de)電(dian)(dian)路來實(shi)現預期的(de)控制(zhi)，而控制(zhi)的(de)精度和靈活性都能(neng)夠保證。電(dian)(dian)磁(ci)閥(fa)(fa)有很(hen)多種，不同(tong)的(de)電(dian)(dian)磁(ci)閥(fa)(fa)在控制(zhi)系(xi)統的(de)不同(tong)位(wei)置(zhi)發揮作(zuo)用(yong)(yong)，最常用(yong)(yong)的(de)是單向(xiang)閥(fa)(fa)、安(an)全閥(fa)(fa)、方向(xiang)控制(zhi)閥(fa)(fa)、速度調節(jie)閥(fa)(fa)等。

電(dian)磁(ci)(ci)閥里有密閉的(de)腔(qiang)，在不同位置(zhi)(zhi)開有通(tong)(tong)(tong)孔(kong)，每個(ge)孔(kong)連接不同的(de)油管，腔(qiang)中間是(shi)活塞，兩面是(shi)兩塊電(dian)磁(ci)(ci)鐵，哪(na)(na)面的(de)磁(ci)(ci)鐵線(xian)圈(quan)通(tong)(tong)(tong)電(dian)閥體(ti)(ti)就(jiu)會(hui)被吸引到哪(na)(na)邊，通(tong)(tong)(tong)過控(kong)制閥體(ti)(ti)的(de)移動(dong)(dong)來開啟或關閉不同的(de)排油孔(kong)，而進(jin)油孔(kong)是(shi)常開的(de)，液(ye)壓油就(jiu)會(hui)進(jin)入不同的(de)排油管，然后通(tong)(tong)(tong)過油的(de)壓力(li)來推(tui)動(dong)(dong)油缸的(de)活塞，活塞又(you)帶動(dong)(dong)活塞桿，活塞桿帶動(dong)(dong)機(ji)械裝置(zhi)(zhi)。這樣通(tong)(tong)(tong)過控(kong)制電(dian)磁(ci)(ci)鐵的(de)電(dian)流通(tong)(tong)(tong)斷就(jiu)控(kong)制了機(ji)械運動(dong)(dong)。

1、電磁閥從原理上分(fen)為三大(da)類：

直(zhi)動式電磁(ci)閥

原理：通電(dian)時，電(dian)磁線圈產生電(dian)磁力(li)把關閉(bi)件(jian)(jian)從閥座上提(ti)起(qi)，閥門打(da)開；斷電(dian)時，電(dian)磁力(li)消(xiao)失，彈簧把關閉(bi)件(jian)(jian)壓(ya)在(zai)閥座上，閥門關閉(bi)。

特點：在(zai)真空、負壓、零壓時能(neng)正常工作，但(dan)通徑一般(ban)不超過(guo)25mm。

分步直動(dong)式電磁閥

原(yuan)理：它是一種直動和先(xian)導式(shi)相結合(he)的原(yuan)理，當(dang)(dang)入口與出口沒有壓(ya)(ya)(ya)(ya)差(cha)時(shi)，通電(dian)后，電(dian)磁力直接把先(xian)導小閥(fa)(fa)(fa)和主(zhu)閥(fa)(fa)(fa)關閉(bi)(bi)件依次向上提起(qi)，閥(fa)(fa)(fa)門(men)打(da)開(kai)。當(dang)(dang)入口與出口達到(dao)啟動壓(ya)(ya)(ya)(ya)差(cha)時(shi)，通電(dian)后，電(dian)磁力先(xian)導小閥(fa)(fa)(fa)，主(zhu)閥(fa)(fa)(fa)下(xia)(xia)腔壓(ya)(ya)(ya)(ya)力上升(sheng)，上腔壓(ya)(ya)(ya)(ya)力下(xia)(xia)降，從而利用壓(ya)(ya)(ya)(ya)差(cha)把主(zhu)閥(fa)(fa)(fa)向上推(tui)(tui)開(kai)；斷電(dian)時(shi)，先(xian)導閥(fa)(fa)(fa)利用彈簧力或介(jie)質(zhi)壓(ya)(ya)(ya)(ya)力推(tui)(tui)動關閉(bi)(bi)件，向下(xia)(xia)移動，使(shi)閥(fa)(fa)(fa)門(men)關閉(bi)(bi)。

特點：在(zai)零壓差或真空、高壓時(shi)亦能可*動作(zuo)，但(dan)功率較大，要求(qiu)必須水(shui)平安裝(zhuang)。

先(xian)導式(shi)電磁(ci)閥(fa)

原理：通(tong)電時，電磁力把先導孔打開，上(shang)腔室壓(ya)力迅速下降，在(zai)關(guan) 閉件(jian)周(zhou)(zhou)圍(wei)(wei)形成上(shang)低下高的壓(ya)差(cha)(cha)，流體(ti)壓(ya)力推動關(guan)閉件(jian)向(xiang)上(shang)移(yi)動，閥(fa)門(men)打開；斷電時，彈簧(huang)力把先導孔關(guan)閉，入口(kou)壓(ya)力通(tong)過旁(pang)通(tong)孔迅速腔室在(zai)關(guan)閥(fa)件(jian)周(zhou)(zhou)圍(wei)(wei)形成下低上(shang)高的壓(ya)差(cha)(cha)，流體(ti)壓(ya)力推動關(guan)閉件(jian)向(xiang)下移(yi)動，關(guan)閉閥(fa)門(men)。

特(te)點：流體壓力范圍上(shang)限(xian)較高，可任意安(an)裝（需定制）但必須滿足流體壓差條件。

2、電磁閥(fa)從閥(fa)結(jie)構和材(cai)料上的不同與原理(li)上的區別，分為六個(ge)分支小類：直(zhi)動(dong)膜(mo)片(pian)結(jie)構、分步(bu)直(zhi)動(dong)膜(mo)片(pian)結(jie)構、先(xian)導膜(mo)片(pian)結(jie)構、直(zhi)動(dong)活(huo)塞結(jie)構、分步(bu)直(zhi)動(dong)活(huo)塞結(jie)構、先(xian)導活(huo)塞結(jie)構。

3、電(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)閥(fa)(fa)(fa)(fa)按照(zhao)功(gong)能分類：水用電(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)閥(fa)(fa)(fa)(fa)、蒸汽電(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)閥(fa)(fa)(fa)(fa)、制冷(leng)電(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)閥(fa)(fa)(fa)(fa)、低(di)溫電(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)閥(fa)(fa)(fa)(fa)、燃氣(qi)電(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)閥(fa)(fa)(fa)(fa)、消防電(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)閥(fa)(fa)(fa)(fa)、氨用電(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)閥(fa)(fa)(fa)(fa)、氣(qi)體電(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)閥(fa)(fa)(fa)(fa)、液體電(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)閥(fa)(fa)(fa)(fa)、微(wei)型電(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)閥(fa)(fa)(fa)(fa)、脈沖電(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)閥(fa)(fa)(fa)(fa)、液壓電(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)閥(fa)(fa)(fa)(fa) 常開(kai)電(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)閥(fa)(fa)(fa)(fa)、油用電(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)閥(fa)(fa)(fa)(fa)、直(zhi)流(liu)電(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)閥(fa)(fa)(fa)(fa)、高壓電(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)閥(fa)(fa)(fa)(fa)、防爆電(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)閥(fa)(fa)(fa)(fa)等。