電(dian)-氣(qi)(qi)(qi)閥(fa)門(men)(men)定(ding)位(wei)器(qi)(qi)是指把電(dian)動(dong)(dong)(dong)控(kong)制(zhi)器(qi)(qi)的(de)輸出信(xin)號(hao)(hao)變為(wei)氣(qi)(qi)(qi)信(xin)號(hao)(hao)去(qu)驅動(dong)(dong)(dong)氣(qi)(qi)(qi)動(dong)(dong)(dong)執行器(qi)(qi)，它具(ju)有電(dian)-氣(qi)(qi)(qi)轉換(huan)器(qi)(qi)和氣(qi)(qi)(qi)動(dong)(dong)(dong)閥(fa)門(men)(men)定(ding)位(wei)器(qi)(qi)兩種作用(yong)(yong)(yong)。電(dian)一(yi)(yi)氣(qi)(qi)(qi)閥(fa)門(men)(men)定(ding)位(wei)器(qi)(qi)一(yi)(yi)方面具(ju)有電(dian)一(yi)(yi)氣(qi)(qi)(qi)轉換(huan)器(qi)(qi)的(de)作用(yong)(yong)(yong)，可(ke)用(yong)(yong)(yong)電(dian)動(dong)(dong)(dong)控(kong)制(zhi)器(qi)(qi)輸出的(de)0~ 10 mA DC或4~20 mADC信(xin)號(hao)(hao)去(qu)操縱氣(qi)(qi)(qi)動(dong)(dong)(dong)執行機構;另一(yi)(yi)方面還具(ju)有氣(qi)(qi)(qi)動(dong)(dong)(dong)閥(fa)門(men)(men)定(ding)位(wei)器(qi)(qi)的(de)作用(yong)(yong)(yong)，可(ke)以使閥(fa)門(men)(men)位(wei)置按控(kong)制(zhi)器(qi)(qi)送來的(de)信(xin)號(hao)(hao)準確定(ding)位(wei)(即(ji)輸入(ru)信(xin)號(hao)(hao)與閥(fa)門(men)(men)位(wei)置呈一(yi)(yi)一(yi)(yi)對應(ying)關系(xi))。

配薄膜執行機構的(de)電(dian)(dian)一(yi)氣閥門定(ding)位(wei)器的(de)動作(zuo)(zuo)原(yuan)理是按力(li)(li)(li)(li)(li)矩(ju)(ju)(ju)平(ping)(ping)衡(heng)原(yuan)理工(gong)作(zuo)(zuo)的(de)。當(dang)信號電(dian)(dian)流通入力(li)(li)(li)(li)(li)矩(ju)(ju)(ju)馬(ma)達1的(de)線圈時，它與(yu)*磁鋼作(zuo)(zuo)用后,對主杠(gang)桿(gan)(gan)產生一(yi)個力(li)(li)(li)(li)(li)矩(ju)(ju)(ju)，于是擋板靠近(jin)噴(pen)嘴，經(jing)放(fang)大(da)器放(fang)大(da)后，送(song)入薄膜氣室使杠(gang)桿(gan)(gan)向(xiang)下(xia)移動,并帶(dai)動反(fan)饋桿(gan)(gan)繞其支(zhi)點4轉(zhuan)動，連在同一(yi)軸(zhou)上的(de)反(fan)饋凸輪(lun)也作(zuo)(zuo)逆(ni)時針(zhen)方向(xiang)轉(zhuan)動，通過(guo)滾(gun)輪(lun)使副杠(gang)桿(gan)(gan)繞其支(zhi)點偏轉(zhuan)，拉伸反(fan)饋彈簧(huang)。當(dang)反(fan)饋彈簧(huang)對主杠(gang)桿(gan)(gan)的(de)拉力(li)(li)(li)(li)(li)與(yu)力(li)(li)(li)(li)(li)矩(ju)(ju)(ju)馬(ma)達作(zuo)(zuo)用在主杠(gang)桿(gan)(gan)上的(de)力(li)(li)(li)(li)(li)兩者力(li)(li)(li)(li)(li)矩(ju)(ju)(ju)平(ping)(ping)衡(heng)時，儀表達到平(ping)(ping)衡(heng)狀(zhuang)態，此時，一(yi)定(ding)的(de)信號電(dian)(dian)流就對應(ying)于一(yi)定(ding)的(de)閥門位(wei)置(zhi)。