塔吊的(de)工作原理是起(qi)(qi)重(zhong)(zhong)(zhong)(zhong)機(ji)(ji)械(xie)通過(guo)(guo)起(qi)(qi)重(zhong)(zhong)(zhong)(zhong)吊鉤或(huo)(huo)其它(ta)取物(wu)裝置起(qi)(qi)升(sheng)(sheng)或(huo)(huo)起(qi)(qi)升(sheng)(sheng)加移動重(zhong)(zhong)(zhong)(zhong)物(wu)。起(qi)(qi)重(zhong)(zhong)(zhong)(zhong)機(ji)(ji)械(xie)的(de)工作過(guo)(guo)程一般(ban)包括(kuo)起(qi)(qi)升(sheng)(sheng)、運行、下(xia)降及(ji)返回(hui)(hui)原位等步驟(zou)。起(qi)(qi)升(sheng)(sheng)機(ji)(ji)構(gou)通過(guo)(guo)取物(wu)裝置從取物(wu)地點把重(zhong)(zhong)(zhong)(zhong)物(wu)提起(qi)(qi)，經(jing)運行、回(hui)(hui)轉或(huo)(huo)變(bian)幅機(ji)(ji)構(gou)把重(zhong)(zhong)(zhong)(zhong)物(wu)移位，在(zai)設定的(de)地點下(xia)放重(zhong)(zhong)(zhong)(zhong)物(wu)后返回(hui)(hui)到原位。

常(chang)見(jian)的驅(qu)動裝置(zhi)有(you)電(dian)(dian)力(li)驅(qu)動、內(nei)(nei)燃機驅(qu)動和(he)人力(li)驅(qu)動等。電(dian)(dian)能是清潔、經濟的能源，電(dian)(dian)力(li)驅(qu)動是現代(dai)起重(zhong)機的主要驅(qu)動型式(shi)，幾乎(hu)所(suo)有(you)的在有(you)限范圍內(nei)(nei)運(yun)行的有(you)軌起重(zhong)機、升降(jiang)機、電(dian)(dian)梯等都(dou)采用電(dian)(dian)力(li)驅(qu)動。

對于(yu)可(ke)以遠距離(li)移動(dong)(dong)的流動(dong)(dong)式(shi)起重機(ji)(如(ru)汽車起重機(ji)、輪(lun)胎起重機(ji)和履帶起重機(ji))多采用內燃(ran)機(ji)驅動(dong)(dong)。人(ren)力驅動(dong)(dong)適用于(yu)一些(xie)輕小起重設備(bei)(bei)，也用作(zuo)某(mou)些(xie)設備(bei)(bei)的輔(fu)助、備(bei)(bei)用驅動(dong)(dong)和意外(或事故狀(zhuang)態)的臨(lin)時動(dong)(dong)力。