液(ye)(ye)(ye)壓(ya)(ya)(ya)缸(gang)工(gong)(gong)作(zuo)過(guo)程：降低風機流量及全(quan)壓(ya)(ya)(ya)時(shi),電動(dong)(dong)(dong)(dong)頭驅(qu)動(dong)(dong)(dong)(dong)控制盤(7)逆時(shi)針(zhen)旋(xuan)轉,帶動(dong)(dong)(dong)(dong)滑(hua)塊(kuai)(12)向(xiang)右移(yi)動(dong)(dong)(dong)(dong)。此時(shi)液(ye)(ye)(ye)壓(ya)(ya)(ya)缸(gang)只隨葉(xie)(xie)輪(lun)(lun)作(zuo)旋(xuan)轉運動(dong)(dong)(dong)(dong),定位軸(1)及與(yu)(yu)(yu)之相(xiang)(xiang)連的(de)(de)雙(shuang)面齒條(tiao)(tiao)(8)靜(jing)止不動(dong)(dong)(dong)(dong)。于是大齒輪(lun)(lun)(10)只能(neng)推動(dong)(dong)(dong)(dong)與(yu)(yu)(yu)之嚙合的(de)(de)單面小齒條(tiao)(tiao)(13)往右移(yi)動(dong)(dong)(dong)(dong)。壓(ya)(ya)(ya)力油(you)(you)口與(yu)(yu)(yu)藍色(se)(se)油(you)(you)道(dao)(dao)相(xiang)(xiang)通,紅(hong)色(se)(se)油(you)(you)道(dao)(dao)與(yu)(yu)(yu)回(hui)油(you)(you)口接通,壓(ya)(ya)(ya)力油(you)(you)從藍色(se)(se)油(you)(you)道(dao)(dao)不斷進入活(huo)塞(sai)(3)右側的(de)(de)液(ye)(ye)(ye)壓(ya)(ya)(ya)油(you)(you)缸(gang)內,使液(ye)(ye)(ye)壓(ya)(ya)(ya)油(you)(you)缸(gang)不斷向(xiang)右移(yi)動(dong)(dong)(dong)(dong)。活(huo)塞(sai)左(zuo)側液(ye)(ye)(ye)壓(ya)(ya)(ya)油(you)(you)缸(gang)內的(de)(de)工(gong)(gong)作(zuo)油(you)(you)從紅(hong)色(se)(se)油(you)(you)道(dao)(dao)通過(guo)回(hui)油(you)(you)孔返(fan)回(hui)油(you)(you)箱(xiang)。液(ye)(ye)(ye)壓(ya)(ya)(ya)油(you)(you)缸(gang)與(yu)(yu)(yu)葉(xie)(xie)輪(lun)(lun)上的(de)(de)每(mei)個動(dong)(dong)(dong)(dong)葉(xie)(xie)片(pian)的(de)(de)調節桿(調節桿連接葉(xie)(xie)柄(bing)，葉(xie)(xie)柄(bing)上有葉(xie)(xie)片(pian))相(xiang)(xiang)連,當液(ye)(ye)(ye)壓(ya)(ya)(ya)油(you)(you)缸(gang)向(xiang)右移(yi)動(dong)(dong)(dong)(dong)時(shi),動(dong)(dong)(dong)(dong)葉(xie)(xie)片(pian)的(de)(de)角度減小,風機輸送流量與(yu)(yu)(yu)全(quan)壓(ya)(ya)(ya)隨即降低。

　　液壓缸反(fan)饋(kui)過(guo)程：當液壓缸向右移(yi)(yi)動(dong)(dong)時(shi),定位軸(1)被(bei)帶(dai)動(dong)(dong)同時(shi)向右移(yi)(yi)動(dong)(dong)。但由(you)于滑塊不動(dong)(dong),所以雙面齒條(8)向右移(yi)(yi)動(dong)(dong)帶(dai)動(dong)(dong)大小齒輪(10、11)使(shi)單面齒條(13)向左移(yi)(yi)動(dong)(dong)。這樣又使(shi)伺(si)服閥將油道(dao)藍色與紅色油道(dao)的(de)油孔關(guan)閉(bi),液壓油缸隨之處在新的(de)平衡位置(zhi)不再移(yi)(yi)動(dong)(dong)。而動(dong)(dong)葉(xie)片亦(yi)在關(guan)小的(de)狀(zhuang)態下工(gong)作(zuo),這就是反(fan)饋(kui)過(guo)程。在反(fan)饋(kui)時(shi)指(zhi)示齒輪帶(dai)動(dong)(dong)指(zhi)示軸(指(zhi)示盤)旋轉(zhuan),將動(dong)(dong)葉(xie)片關(guan)小的(de)角度顯示出來。