一、什么是電磁閥
電磁閥是(shi)(shi)用(yong)電磁控(kong)制(zhi)(zhi)的(de)工業設備,是(shi)(shi)用(yong)來控(kong)制(zhi)(zhi)流體的(de)自動化(hua)基(ji)礎元件(jian),屬(shu)于執行器(qi),并不(bu)限于液壓、氣動。用(yong)在工業控(kong)制(zhi)(zhi)系(xi)統中調整介質的(de)方向、流量、速度(du)和(he)其他的(de)參數。電磁閥可以配(pei)合不(bu)同的(de)電路來實現預期的(de)控(kong)制(zhi)(zhi),而控(kong)制(zhi)(zhi)的(de)精度(du)和(he)靈活性(xing)都(dou)能(neng)夠保證。
二、電磁閥工作原理
電(dian)(dian)磁(ci)閥里(li)有密閉的腔,在不(bu)(bu)同(tong)(tong)位置(zhi)開有通孔(kong)(kong),每(mei)個(ge)孔(kong)(kong)連接(jie)不(bu)(bu)同(tong)(tong)的油(you)管,腔中(zhong)間是(shi)活塞(sai)(sai),兩面是(shi)兩塊(kuai)電(dian)(dian)磁(ci)鐵,哪面的磁(ci)鐵線圈通電(dian)(dian)閥體就會被吸(xi)引(yin)到哪邊,通過(guo)控(kong)制(zhi)閥體的移動來(lai)開啟或(huo)關(guan)閉不(bu)(bu)同(tong)(tong)的排(pai)油(you)孔(kong)(kong),而進(jin)油(you)孔(kong)(kong)是(shi)常開的,液壓(ya)(ya)油(you)就會進(jin)入不(bu)(bu)同(tong)(tong)的排(pai)油(you)管,然后通過(guo)油(you)的壓(ya)(ya)力來(lai)推動油(you)缸(gang)的活塞(sai)(sai),活塞(sai)(sai)又(you)帶動活塞(sai)(sai)桿,活塞(sai)(sai)桿帶動機(ji)械裝置(zhi)。這(zhe)樣通過(guo)控(kong)制(zhi)電(dian)(dian)磁(ci)鐵的電(dian)(dian)流通斷就控(kong)制(zhi)了機(ji)械運動。
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(yuan)理(li):通(tong)電(dian)(dian)時,電(dian)(dian)磁線圈產生(sheng)電(dian)(dian)磁力把(ba)關(guan)閉件從閥(fa)(fa)(fa)座(zuo)上(shang)提起,閥(fa)(fa)(fa)門(men)打開;斷電(dian)(dian)時,電(dian)(dian)磁力消(xiao)失,彈簧把(ba)關(guan)閉件壓在閥(fa)(fa)(fa)座(zuo)上(shang),閥(fa)(fa)(fa)門(men)關(guan)閉。
特點:在真空、負壓、零壓時能正常(chang)工作,但通徑一般不(bu)超過25mm。
(2)分步直動式電磁閥
原理:它是一種直(zhi)動和先導(dao)(dao)式相結合的(de)原理,當入口(kou)與出口(kou)沒有(you)壓(ya)差(cha)時,通電(dian)后,電(dian)磁力直(zhi)接把(ba)先導(dao)(dao)小(xiao)閥(fa)和主閥(fa)關(guan)閉件依(yi)次(ci)向上(shang)提起(qi),閥(fa)門打開。當入口(kou)與出口(kou)達到啟動壓(ya)差(cha)時,通電(dian)后,電(dian)磁力先導(dao)(dao)小(xiao)閥(fa),主閥(fa)下腔(qiang)壓(ya)力上(shang)升(sheng),上(shang)腔(qiang)壓(ya)力下降,從而利(li)用壓(ya)差(cha)把(ba)主閥(fa)向上(shang)推(tui)開;斷電(dian)時,先導(dao)(dao)閥(fa)利(li)用彈簧力或介質壓(ya)力推(tui)動關(guan)閉件,向下移動,使閥(fa)門關(guan)閉。
特點(dian):在零壓差或真空、高壓時亦能可*動作,但功率較大(da),要求必須水平(ping)安(an)裝(zhuang)。
(3)先導式電磁閥
原理:通電(dian)時,電(dian)磁力(li)把先導(dao)孔打開,上(shang)(shang)腔室壓(ya)力(li)迅(xun)速下降,在(zai)關(guan) 閉(bi)(bi)件(jian)周(zhou)圍形成(cheng)上(shang)(shang)低(di)下高的(de)壓(ya)差,流(liu)體壓(ya)力(li)推動(dong)關(guan)閉(bi)(bi)件(jian)向上(shang)(shang)移動(dong),閥(fa)(fa)(fa)門(men)打開;斷電(dian)時,彈簧力(li)把先導(dao)孔關(guan)閉(bi)(bi),入口壓(ya)力(li)通過旁(pang)通孔迅(xun)速腔室在(zai)關(guan)閥(fa)(fa)(fa)件(jian)周(zhou)圍形成(cheng)下低(di)上(shang)(shang)高的(de)壓(ya)差,流(liu)體壓(ya)力(li)推動(dong)關(guan)閉(bi)(bi)件(jian)向下移動(dong),關(guan)閉(bi)(bi)閥(fa)(fa)(fa)門(men)。
特點:流體壓力范圍上限(xian)較高,可任(ren)意(yi)安裝(需定制)但必(bi)須滿足流體壓差條件。
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(mo)(mo)片(pian)結(jie)(jie)構(gou)、分(fen)步(bu)直動膜(mo)(mo)片(pian)結(jie)(jie)構(gou)、先(xian)導膜(mo)(mo)片(pian)結(jie)(jie)構(gou)、直動活塞(sai)結(jie)(jie)構(gou)、分(fen)步(bu)直動活塞(sai)結(jie)(jie)構(gou)、先(xian)導活塞(sai)結(jie)(jie)構(gou)。
3、電磁閥按照功能分類:水(shui)用電(dian)(dian)(dian)磁(ci)閥(fa)(fa)、蒸汽電(dian)(dian)(dian)磁(ci)閥(fa)(fa)、制(zhi)冷電(dian)(dian)(dian)磁(ci)閥(fa)(fa)、低溫電(dian)(dian)(dian)磁(ci)閥(fa)(fa)、燃氣(qi)電(dian)(dian)(dian)磁(ci)閥(fa)(fa)、消防(fang)電(dian)(dian)(dian)磁(ci)閥(fa)(fa)、氨用電(dian)(dian)(dian)磁(ci)閥(fa)(fa)、氣(qi)體電(dian)(dian)(dian)磁(ci)閥(fa)(fa)、液(ye)體電(dian)(dian)(dian)磁(ci)閥(fa)(fa)、微型(xing)電(dian)(dian)(dian)磁(ci)閥(fa)(fa)、脈沖電(dian)(dian)(dian)磁(ci)閥(fa)(fa)、液(ye)壓(ya)電(dian)(dian)(dian)磁(ci)閥(fa)(fa)、常(chang)開電(dian)(dian)(dian)磁(ci)閥(fa)(fa)、油用電(dian)(dian)(dian)磁(ci)閥(fa)(fa)、直流電(dian)(dian)(dian)磁(ci)閥(fa)(fa)、高壓(ya)電(dian)(dian)(dian)磁(ci)閥(fa)(fa)、防(fang)爆電(dian)(dian)(dian)磁(ci)閥(fa)(fa)等。