液(ye)(ye)(ye)壓(ya)(ya)(ya)機的(de)驅(qu)(qu)動(dong)(dong)(dong)(dong)系(xi)(xi)統(tong)(tong)(tong)主要(yao)有泵(beng)(beng)(beng)(beng)直接(jie)驅(qu)(qu)動(dong)(dong)(dong)(dong)和(he)(he)泵(beng)(beng)(beng)(beng)-蓄(xu)(xu)能(neng)(neng)器(qi)(qi)驅(qu)(qu)動(dong)(dong)(dong)(dong)兩種(zhong)(zhong)型(xing)(xing)式。泵(beng)(beng)(beng)(beng)直接(jie)驅(qu)(qu)動(dong)(dong)(dong)(dong) 這(zhe)(zhe)種(zhong)(zhong)驅(qu)(qu)動(dong)(dong)(dong)(dong) 系(xi)(xi)統(tong)(tong)(tong)的(de)泵(beng)(beng)(beng)(beng)向(xiang)液(ye)(ye)(ye)壓(ya)(ya)(ya)缸提供高壓(ya)(ya)(ya)工(gong)(gong)(gong)作(zuo)液(ye)(ye)(ye)體，配流閥用來(lai)改變供液(ye)(ye)(ye)方向(xiang)，溢流閥用來(lai)調節系(xi)(xi)統(tong)(tong)(tong)的(de)限定壓(ya)(ya)(ya)強，同時(shi)(shi)起安全溢流作(zuo)用。這(zhe)(zhe)種(zhong)(zhong)驅(qu)(qu)動(dong)(dong)(dong)(dong)系(xi)(xi)統(tong)(tong)(tong)環節少(shao),結構簡單,壓(ya)(ya)(ya)強能(neng)(neng)按所(suo)(suo)需的(de)工(gong)(gong)(gong)作(zuo)力自動(dong)(dong)(dong)(dong)增減，減少(shao)了電能(neng)(neng)消(xiao)耗，但(dan)須由(you)液(ye)(ye)(ye)壓(ya)(ya)(ya)機的(de)大工(gong)(gong)(gong)作(zuo)力和(he)(he)高工(gong)(gong)(gong)作(zuo)速度來(lai)決定泵(beng)(beng)(beng)(beng)及其(qi)驅(qu)(qu)動(dong)(dong)(dong)(dong)電機的(de)容(rong)量(liang)。這(zhe)(zhe)種(zhong)(zhong)型(xing)(xing)式的(de)驅(qu)(qu)動(dong)(dong)(dong)(dong)系(xi)(xi)統(tong)(tong)(tong)多用于(yu)中小(xiao)型(xing)(xing)液(ye)(ye)(ye)壓(ya)(ya)(ya)機，也有用泵(beng)(beng)(beng)(beng)直接(jie)驅(qu)(qu)動(dong)(dong)(dong)(dong)的(de)大型(xing)(xing)（如(ru)120000千牛）自由(you)鍛造(zao)水壓(ya)(ya)(ya)機。　泵(beng)(beng)(beng)(beng)-蓄(xu)(xu)能(neng)(neng)器(qi)(qi)驅(qu)(qu)動(dong)(dong)(dong)(dong) 在這(zhe)(zhe)種(zhong)(zhong)驅(qu)(qu)動(dong)(dong)(dong)(dong)系(xi)(xi)統(tong)(tong)(tong)中有一(yi)個或一(yi)組蓄(xu)(xu)能(neng)(neng)器(qi)(qi)。當(dang)泵(beng)(beng)(beng)(beng)所(suo)(suo)供給的(de)高壓(ya)(ya)(ya)工(gong)(gong)(gong)作(zuo)液(ye)(ye)(ye)有余量(liang)時(shi)(shi)，由(you)蓄(xu)(xu)能(neng)(neng)器(qi)(qi)儲存；而當(dang)供給量(liang)不足于(yu)需要(yao)時(shi)(shi)，便由(you)蓄(xu)(xu)能(neng)(neng)器(qi)(qi)補充供給。采用這(zhe)(zhe)種(zhong)(zhong)系(xi)(xi)統(tong)(tong)(tong)可以按高壓(ya)(ya)(ya)工(gong)(gong)(gong)作(zuo)液(ye)(ye)(ye)的(de)平均用量(liang)選用泵(beng)(beng)(beng)(beng)和(he)(he)電動(dong)(dong)(dong)(dong)機的(de)容(rong)量(liang)，但(dan)因為工(gong)(gong)(gong)作(zuo)液(ye)(ye)(ye)的(de)壓(ya)(ya)(ya)強是(shi)恒定的(de)，電能(neng)(neng)消(xiao)耗量(liang)較大，并且系(xi)(xi)統(tong)(tong)(tong)的(de)環節多，結構比較復雜(za)。這(zhe)(zhe)種(zhong)(zhong)驅(qu)(qu)動(dong)(dong)(dong)(dong)系(xi)(xi)統(tong)(tong)(tong)多用于(yu)大型(xing)(xing)液(ye)(ye)(ye)壓(ya)(ya)(ya)機，或者(zhe)用一(yi)套驅(qu)(qu)動(dong)(dong)(dong)(dong)系(xi)(xi)統(tong)(tong)(tong)驅(qu)(qu)動(dong)(dong)(dong)(dong)數(shu)臺液(ye)(ye)(ye)壓(ya)(ya)(ya)機。