液壓小型(xing)挖(wa)掘(jue)(jue)機的(de)作(zuo)(zuo)(zuo)業(ye)過程(cheng)包括以(yi)下(xia)幾(ji)個動(dong)(dong)作(zuo)(zuo)(zuo)動(dong)(dong)臂升降、斗桿收(shou)放(fang)、鏟斗裝卸、轉(zhuan)臺(tai)回(hui)轉(zhuan)、整機行(xing)走(zou)以(yi)及其(qi)(qi)它(ta)輔(fu)助(zhu)動(dong)(dong)作(zuo)(zuo)(zuo)。除(chu)了(le)(le)輔(fu)助(zhu)動(dong)(dong)作(zuo)(zuo)(zuo)例(li)如整機轉(zhuan)向等不需全(quan)(quan)功率驅動(dong)(dong)以(yi)外，其(qi)(qi)它(ta)都是液壓小型(xing)挖(wa)掘(jue)(jue)機的(de)主要(yao)動(dong)(dong)作(zuo)(zuo)(zuo)，要(yao)考慮全(quan)(quan)功率驅動(dong)(dong)。由于液壓小型(xing)挖(wa)掘(jue)(jue)機的(de)作(zuo)(zuo)(zuo)業(ye)對象和(he)工(gong)作(zuo)(zuo)(zuo)條件變(bian)(bian)化(hua)較大，主機的(de)工(gong)作(zuo)(zuo)(zuo)有兩項(xiang)特殊要(yao)求其(qi)(qi)一是實現各種主要(yao)動(dong)(dong)作(zuo)(zuo)(zuo)時(shi)，阻力與作(zuo)(zuo)(zuo)業(ye)速度隨時(shi)變(bian)(bian)化(hua)，因此，要(yao)求液壓缸和(he)液壓馬達的(de)壓力和(he)流(liu)量(liang)也能相(xiang)應變(bian)(bian)化(hua)其(qi)(qi)二是為了(le)(le)充分(fen)利用(yong)發動(dong)(dong)機功率和(he)縮短作(zuo)(zuo)(zuo)業(ye)循環時(shi)間，工(gong)作(zuo)(zuo)(zuo)過程(cheng)中往(wang)往(wang)要(yao)求有兩個主要(yao)動(dong)(dong)作(zuo)(zuo)(zuo)例(li)如提升與回(hui)轉(zhuan)同時(shi)進行(xing)的(de)復合動(dong)(dong)作(zuo)(zuo)(zuo)。

液(ye)壓小型挖掘機(ji)一(yi)個作業循環的(de)組成和動作的(de)復合主要包(bao)括：

1.挖(wa)掘：通常以鏟斗液(ye)壓(ya)缸(gang)或(huo)(huo)斗桿(gan)液(ye)壓(ya)缸(gang)進行挖(wa)掘，或(huo)(huo)者(zhe)兩者(zhe)配(pei)(pei)合進行挖(wa)掘，因(yin)此(ci)，在此(ci)過(guo)程中主要(yao)是鏟斗和斗桿(gan)的復合動(dong)作，必要(yao)時，配(pei)(pei)以動(dong)臂動(dong)作。

 2.滿斗舉升(sheng)回轉(zhuan)：挖掘(jue)結束，動臂液壓缸將(jiang)動臂頂起，滿斗提升(sheng)，同時(shi)回轉(zhuan)液壓馬達使轉(zhuan)臺轉(zhuan)向卸(xie)土(tu)處，此時(shi)主(zhu)要是動臂和回轉(zhuan)的復合動作。

3.卸(xie)載(zai)：轉到(dao)卸(xie)土(tu)點時，轉臺制(zhi)動(dong)(dong)，用斗(dou)(dou)(dou)桿液(ye)壓(ya)缸(gang)調節卸(xie)載(zai)半徑，然后鏟(chan)斗(dou)(dou)(dou)液(ye)壓(ya)缸(gang)回縮，鏟(chan)斗(dou)(dou)(dou)卸(xie)載(zai)。為了調整卸(xie)載(zai)位置，還要有動(dong)(dong)臂(bei)液(ye)壓(ya)缸(gang)的配合，此(ci)時是斗(dou)(dou)(dou)桿和鏟(chan)斗(dou)(dou)(dou)的復合動(dong)(dong)作，間以(yi)動(dong)(dong)臂(bei)動(dong)(dong)作。

4.空(kong)斗(dou)返回：卸(xie)載結束，轉(zhuan)臺(tai)反向回轉(zhuan)，動(dong)臂液壓缸(gang)和(he)斗(dou)桿(gan)液壓缸(gang)配(pei)合(he)，把空(kong)斗(dou)放到新的(de)挖掘點(dian)，此時是回轉(zhuan)和(he)動(dong)臂或(huo)斗(dou)桿(gan)的(de)復合(he)動(dong)作。

綜上所述(shu)，整個作(zuo)(zuo)業循環(huan)過(guo)程(cheng)(cheng)為首先(xian)液壓小(xiao)型挖(wa)掘(jue)機(ji)驅動(dong)(dong)(dong)(dong)(dong)行走馬達和(he)配套土(tu)(tu)方(fang)(fang)運(yun)輸(shu)車輛(liang)(liang)一(yi)起(qi)進入作(zuo)(zuo)業面(mian)(mian)，運(yun)輸(shu)車輛(liang)(liang)倒車、調整，停靠在(zai)小(xiao)型挖(wa)掘(jue)機(ji)的(de)側方(fang)(fang)或后方(fang)(fang)。小(xiao)型挖(wa)掘(jue)機(ji)司機(ji)扳動(dong)(dong)(dong)(dong)(dong)操(cao)(cao)縱手(shou)柄，使(shi)回(hui)(hui)(hui)轉(zhuan)馬達控(kong)制閥(fa)(fa)接(jie)通(tong)，于是回(hui)(hui)(hui)轉(zhuan)馬達轉(zhuan)動(dong)(dong)(dong)(dong)(dong)并(bing)帶(dai)動(dong)(dong)(dong)(dong)(dong)上部(bu)平臺(tai)回(hui)(hui)(hui)轉(zhuan)，使(shi)工(gong)作(zuo)(zuo)裝(zhuang)置轉(zhuan)向(xiang)(xiang)挖(wa)掘(jue)地(di)點，在(zai)執(zhi)行上述(shu)過(guo)程(cheng)(cheng)的(de)同時操(cao)(cao)縱動(dong)(dong)(dong)(dong)(dong)臂(bei)油(you)(you)缸(gang)換向(xiang)(xiang)閥(fa)(fa)，使(shi)動(dong)(dong)(dong)(dong)(dong)臂(bei)油(you)(you)缸(gang)上腔(qiang)(qiang)進油(you)(you)，將動(dong)(dong)(dong)(dong)(dong)臂(bei)下(xia)降，直至鏟(chan)(chan)(chan)斗(dou)接(jie)觸(chu)地(di)面(mian)(mian)，然后司機(ji)操(cao)(cao)縱斗(dou)桿油(you)(you)缸(gang)和(he)鏟(chan)(chan)(chan)斗(dou)油(you)(you)缸(gang)的(de)換向(xiang)(xiang)閥(fa)(fa)，使(shi)兩(liang)者的(de)大腔(qiang)(qiang)進油(you)(you)，配合(he)動(dong)(dong)(dong)(dong)(dong)作(zuo)(zuo)以(yi)加快作(zuo)(zuo)業進度，進行復合(he)動(dong)(dong)(dong)(dong)(dong)作(zuo)(zuo)的(de)挖(wa)掘(jue)和(he)裝(zhuang)載，鏟(chan)(chan)(chan)斗(dou)裝(zhuang)滿后將斗(dou)桿油(you)(you)缸(gang)和(he)鏟(chan)(chan)(chan)斗(dou)油(you)(you)缸(gang)的(de)操(cao)(cao)縱手(shou)柄扳回(hui)(hui)(hui)中位(wei)，使(shi)鏟(chan)(chan)(chan)斗(dou)和(he)斗(dou)桿油(you)(you)缸(gang)閉鎖，再操(cao)(cao)縱動(dong)(dong)(dong)(dong)(dong)臂(bei)油(you)(you)缸(gang)換向(xiang)(xiang)閥(fa)(fa)，使(shi)動(dong)(dong)(dong)(dong)(dong)臂(bei)油(you)(you)缸(gang)的(de)下(xia)腔(qiang)(qiang)進油(you)(you)，將動(dong)(dong)(dong)(dong)(dong)臂(bei)提升，舉起(qi)裝(zhuang)滿土(tu)(tu)的(de)鏟(chan)(chan)(chan)斗(dou)離開(kai)工(gong)作(zuo)(zuo)面(mian)(mian)，隨即扳動(dong)(dong)(dong)(dong)(dong)平臺(tai)回(hui)(hui)(hui)轉(zhuan)換向(xiang)(xiang)閥(fa)(fa)手(shou)柄，使(shi)上部(bu)平臺(tai)回(hui)(hui)(hui)轉(zhuan)，帶(dai)動(dong)(dong)(dong)(dong)(dong)鏟(chan)(chan)(chan)斗(dou)轉(zhuan)至運(yun)輸(shu)車輛(liang)(liang)上方(fang)(fang)，再操(cao)(cao)縱斗(dou)桿油(you)(you)缸(gang)使(shi)斗(dou)桿高度稍降一(yi)些，并(bing)在(zai)適當的(de)高度操(cao)(cao)縱鏟(chan)(chan)(chan)斗(dou)油(you)(you)缸(gang)使(shi)鏟(chan)(chan)(chan)斗(dou)卸土(tu)(tu)。土(tu)(tu)方(fang)(fang)卸完后，使(shi)平臺(tai)反(fan)轉(zhuan)并(bing)降低動(dong)(dong)(dong)(dong)(dong)臂(bei)，直至鏟(chan)(chan)(chan)斗(dou)回(hui)(hui)(hui)到作(zuo)(zuo)業點上方(fang)(fang)，以(yi)便進行下(xia)一(yi)工(gong)作(zuo)(zuo)循環(huan)。