一、什么是電磁閥
電磁閥是(shi)(shi)用(yong)電磁控制(zhi)的(de)(de)工業(ye)設備(bei),是(shi)(shi)用(yong)來(lai)控制(zhi)流(liu)體的(de)(de)自(zi)動化基礎元件,屬于執行器,并不限(xian)于液(ye)壓、氣(qi)動。用(yong)在工業(ye)控制(zhi)系統中(zhong)調整介(jie)質的(de)(de)方(fang)向、流(liu)量(liang)、速度(du)和其他的(de)(de)參數。電磁閥(fa)可以配合(he)不同(tong)的(de)(de)電路來(lai)實現預期的(de)(de)控制(zhi),而控制(zhi)的(de)(de)精(jing)度(du)和靈活性都(dou)能夠保證。
二、電磁閥工作原理
電(dian)磁(ci)閥里有密(mi)閉(bi)的(de)(de)腔,在不(bu)同(tong)位置(zhi)開有通(tong)孔,每個(ge)孔連接不(bu)同(tong)的(de)(de)油管,腔中間是(shi)活塞,兩面(mian)是(shi)兩塊電(dian)磁(ci)鐵,哪面(mian)的(de)(de)磁(ci)鐵線圈通(tong)電(dian)閥體就(jiu)會被吸引到(dao)哪邊,通(tong)過(guo)控(kong)制閥體的(de)(de)移(yi)動(dong)來開啟(qi)或關閉(bi)不(bu)同(tong)的(de)(de)排(pai)油孔,而進油孔是(shi)常開的(de)(de),液壓(ya)油就(jiu)會進入不(bu)同(tong)的(de)(de)排(pai)油管,然后通(tong)過(guo)油的(de)(de)壓(ya)力(li)來推動(dong)油缸的(de)(de)活塞,活塞又帶動(dong)活塞桿,活塞桿帶動(dong)機械裝置(zhi)。這樣通(tong)過(guo)控(kong)制電(dian)磁(ci)鐵的(de)(de)電(dian)流通(tong)斷就(jiu)控(kong)制了機械運(yun)動(dong)。
三、電磁閥有幾種類型
1、電磁閥從原理上分為三大類:
(1)直動式電磁閥
原理:通(tong)電(dian)時(shi),電(dian)磁(ci)(ci)線圈(quan)產生電(dian)磁(ci)(ci)力(li)把關(guan)閉(bi)件(jian)從閥(fa)(fa)座(zuo)上(shang)提起,閥(fa)(fa)門打開;斷電(dian)時(shi),電(dian)磁(ci)(ci)力(li)消失,彈(dan)簧把關(guan)閉(bi)件(jian)壓在閥(fa)(fa)座(zuo)上(shang),閥(fa)(fa)門關(guan)閉(bi)。
特點(dian):在真空(kong)、負壓(ya)、零壓(ya)時(shi)能正常工作,但通徑一般不超過25mm。
(2)分步直動式電磁閥
原(yuan)理(li):它是一種直動和先(xian)(xian)導(dao)(dao)式相結(jie)合(he)的原(yuan)理(li),當入口(kou)(kou)與出口(kou)(kou)沒有壓差時,通電(dian)后,電(dian)磁力直接把(ba)先(xian)(xian)導(dao)(dao)小閥(fa)和主閥(fa)關閉(bi)件(jian)依次向(xiang)上提起(qi),閥(fa)門打開。當入口(kou)(kou)與出口(kou)(kou)達到啟(qi)動壓差時,通電(dian)后,電(dian)磁力先(xian)(xian)導(dao)(dao)小閥(fa),主閥(fa)下腔(qiang)(qiang)壓力上升,上腔(qiang)(qiang)壓力下降,從而利(li)用(yong)壓差把(ba)主閥(fa)向(xiang)上推開;斷電(dian)時,先(xian)(xian)導(dao)(dao)閥(fa)利(li)用(yong)彈簧力或介質壓力推動關閉(bi)件(jian),向(xiang)下移動,使閥(fa)門關閉(bi)。
特(te)點:在(zai)零壓(ya)差或真空、高壓(ya)時(shi)亦能可*動作,但(dan)功率較大,要求必須水(shui)平(ping)安裝。
(3)先導式電磁閥
原理:通(tong)電(dian)時,電(dian)磁力把(ba)(ba)先(xian)導孔打開(kai),上腔(qiang)室壓(ya)力迅(xun)速下(xia)(xia)降(jiang),在(zai)關 閉(bi)件(jian)周圍(wei)形成上低(di)(di)下(xia)(xia)高的(de)(de)壓(ya)差(cha),流體壓(ya)力推(tui)(tui)動關閉(bi)件(jian)向(xiang)上移動,閥(fa)門(men)打開(kai);斷電(dian)時,彈(dan)簧力把(ba)(ba)先(xian)導孔關閉(bi),入口壓(ya)力通(tong)過旁(pang)通(tong)孔迅(xun)速腔(qiang)室在(zai)關閥(fa)件(jian)周圍(wei)形成下(xia)(xia)低(di)(di)上高的(de)(de)壓(ya)差(cha),流體壓(ya)力推(tui)(tui)動關閉(bi)件(jian)向(xiang)下(xia)(xia)移動,關閉(bi)閥(fa)門(men)。
特點:流體壓(ya)力范圍上限較(jiao)高,可任意安裝(需定制(zhi))但必須滿(man)足流體壓(ya)差條件。
2、電磁閥從閥結構和材料上的不同與原理上的區別,分為六個分支小類:直動膜片結構(gou)(gou)(gou)、分步(bu)直動膜片結構(gou)(gou)(gou)、先導膜片結構(gou)(gou)(gou)、直動活(huo)塞(sai)結構(gou)(gou)(gou)、分步(bu)直動活(huo)塞(sai)結構(gou)(gou)(gou)、先導活(huo)塞(sai)結構(gou)(gou)(gou)。
3、電磁閥按照功能分類:水用(yong)電(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)(ci)(ci)閥(fa)(fa)、蒸汽電(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)(ci)(ci)閥(fa)(fa)、制冷電(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)(ci)(ci)閥(fa)(fa)、低溫電(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)(ci)(ci)閥(fa)(fa)、燃氣(qi)電(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)(ci)(ci)閥(fa)(fa)、消(xiao)防(fang)電(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)(ci)(ci)閥(fa)(fa)、氨用(yong)電(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)(ci)(ci)閥(fa)(fa)、氣(qi)體電(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)(ci)(ci)閥(fa)(fa)、液體電(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)(ci)(ci)閥(fa)(fa)、微(wei)型(xing)電(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)(ci)(ci)閥(fa)(fa)、脈沖電(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)(ci)(ci)閥(fa)(fa)、液壓(ya)電(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)(ci)(ci)閥(fa)(fa)、常開電(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)(ci)(ci)閥(fa)(fa)、油用(yong)電(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)(ci)(ci)閥(fa)(fa)、直流電(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)(ci)(ci)閥(fa)(fa)、高壓(ya)電(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)(ci)(ci)閥(fa)(fa)、防(fang)爆電(dian)(dian)(dian)(dian)磁(ci)(ci)(ci)(ci)(ci)(ci)閥(fa)(fa)等。