直(zhi)線(xian)(xian)導軌(gui)(gui)又稱線(xian)(xian)軌(gui)(gui)、滑(hua)(hua)軌(gui)(gui)、線(xian)(xian)性導軌(gui)(gui)、線(xian)(xian)性滑(hua)(hua)軌(gui)(gui)，用于高精(jing)或高速直(zhi)線(xian)(xian)往(wang)復(fu)運(yun)動(dong)場合(he)，且(qie)可(ke)以承擔一(yi)定的扭矩，可(ke)在高負載的情況下(xia)實現(xian)高精(jing)度的直(zhi)線(xian)(xian)運(yun)動(dong)。

直(zhi)(zhi)線(xian)(xian)導(dao)(dao)(dao)(dao)軌(gui)運(yun)動的(de)(de)(de)作用(yong)(yong)(yong)是用(yong)(yong)(yong)來支撐和引(yin)導(dao)(dao)(dao)(dao)運(yun)動部件(jian)，按給定(ding)的(de)(de)(de)方向做往復直(zhi)(zhi)線(xian)(xian)運(yun)動。　直(zhi)(zhi)線(xian)(xian)軸承主要用(yong)(yong)(yong)在自動化(hua)機械上比(bi)較多,像直(zhi)(zhi)線(xian)(xian)導(dao)(dao)(dao)(dao)軌(gui)主要是用(yong)(yong)(yong)在精(jing)度(du)要求比(bi)較高(gao)的(de)(de)(de)機械結構(gou)上,直(zhi)(zhi)線(xian)(xian)導(dao)(dao)(dao)(dao)軌(gui)的(de)(de)(de)移(yi)動元件(jian)和固定(ding)元件(jian)之(zhi)間(jian)不用(yong)(yong)(yong)中間(jian)介質(zhi)，而用(yong)(yong)(yong)滾(gun)動鋼球。可以理(li)解為(wei)是一種(zhong)滾(gun)動導(dao)(dao)(dao)(dao)引(yin)，是由鋼珠(zhu)在滑(hua)塊(kuai)跟導(dao)(dao)(dao)(dao)軌(gui)之(zhi)間(jian)無限滾(gun)動循環(huan)， 從而使負載平(ping)臺沿著(zhu)導(dao)(dao)(dao)(dao)軌(gui)輕易的(de)(de)(de)高(gao)精(jing)度(du)線(xian)(xian)性運(yun)動，并(bing)將摩擦系數降至平(ping)常傳統滑(hua)動導(dao)(dao)(dao)(dao)引(yin)的(de)(de)(de)五(wu)十分之(zhi)一，能輕易地(di)達到(dao)很高(gao)的(de)(de)(de)定(ding)位(wei)精(jing)度(du)。滑(hua)塊(kuai)跟導(dao)(dao)(dao)(dao)軌(gui)間(jian)末制(zhi)單元設計，使線(xian)(xian)形導(dao)(dao)(dao)(dao)軌(gui)同時(shi)承受(shou)上下左(zuo)右等各方向的(de)(de)(de)負荷，回流系統及精(jing)簡化(hua)的(de)(de)(de)結構(gou)設計讓線(xian)(xian)性導(dao)(dao)(dao)(dao)軌(gui)有(you)更(geng)平(ping)順且低(di)噪音的(de)(de)(de)運(yun)動。

滑(hua)塊-使運動由曲(qu)線(xian)轉變為(wei)直(zhi)線(xian)。

直線導軌主要是(shi)用(yong)(yong)在精度要求比較高(gao)的機(ji)械結(jie)構上(shang),直線導軌的移動元件(jian)和固定元件(jian)之間不(bu)用(yong)(yong)中間介質，而用(yong)(yong)滾動鋼(gang)球。因為滾動鋼(gang)球適(shi)應于高(gao)速運動、摩(mo)擦(ca)系(xi)數小、靈(ling)敏度高(gao)，滿足運動部件(jian)的工(gong)作要求，被廣泛應用(yong)(yong)在自動化(hua)機(ji)械上(shang)比較多(duo),像磨床(chuang)(chuang)、銑床(chuang)(chuang)、車床(chuang)(chuang)、檢(jian)測(ce)儀器(qi)設備、木工(gong)機(ji)械、搬運機(ji)械、傳送(song)裝(zhuang)置、自動化(hua)機(ji)械、半導體機(ji)械、包裝(zhuang)機(ji)械、機(ji)械手臂、自動化(hua)機(ji)床(chuang)(chuang)、激光(guang)行(xing)業(ye)、汽車制造、新(xin)能源等行(xing)業(ye)。