DIF-L10H1、DIF-L20H1直通單向(xiang)(xiang)閥(fa)用(yong)(yong)(yong)以防止油(you)液(ye)反(fan)向(xiang)(xiang)流(liu)動(dong)。但在液(ye)壓(ya)(ya)回路中(zhong)(zhong)需(xu)要油(you)流(liu)反(fan)向(xiang)(xiang)流(liu)動(dong)時又(you)可(ke)利用(yong)(yong)(yong)控(kong)制(zhi)油(you)壓(ya)(ya)，打開(kai)單向(xiang)(xiang)閥(fa)，使油(you)流(liu)在兩個方向(xiang)(xiang)都可(ke)流(liu)動(dong)。單向(xiang)(xiang)閥(fa)是指依靠介質(zhi)本身(shen)流(liu)動(dong)而(er)自動(dong)開(kai)、閉閥(fa)瓣，用(yong)(yong)(yong)來防止介質(zhi)倒流(liu)的閥(fa)門，又(you)稱逆止閥(fa)、單向(xiang)(xiang)閥(fa)、逆流(liu)閥(fa)、和(he)背壓(ya)(ya)閥(fa)。液(ye)控(kong)單向(xiang)(xiang)閥(fa)采用(yong)(yong)(yong)錐形(xing)閥(fa)芯，因此密(mi)封(feng)(feng)性能(neng)好。在要求封(feng)(feng)閉油(you)路時，可(ke)用(yong)(yong)(yong)此閥(fa)作為油(you)路的單向(xiang)(xiang)鎖(suo)緊而(er)起保壓(ya)(ya)作用(yong)(yong)(yong)。液(ye)控(kong)單向(xiang)(xiang)閥(fa)控(kong)制(zhi)油(you)的泄漏(lou)方式有(you)內(nei)泄式和(he)外(wai)(wai)泄式二種。在油(you)流(liu)反(fan)向(xiang)(xiang)出(chu)口無背壓(ya)(ya)的油(you)路中(zhong)(zhong)可(ke)用(yong)(yong)(yong)內(nei)泄式;否則需(xu)用(yong)(yong)(yong)外(wai)(wai)泄式，以降(jiang)低控(kong)制(zhi)油(you)壓(ya)(ya)力。