直線導軌(gui)又稱線軌(gui)、滑軌(gui)、線性導軌(gui)、線性滑軌(gui)，用于高精或高速直線往復運(yun)動(dong)場合，且(qie)可(ke)以承(cheng)擔一定(ding)的(de)扭矩(ju)，可(ke)在高負(fu)載的(de)情況下實現(xian)高精度的(de)直線運(yun)動(dong)。

直(zhi)線(xian)(xian)導軌(gui)(gui)運(yun)動(dong)(dong)的(de)作用(yong)(yong)是用(yong)(yong)來(lai)支撐和引(yin)導運(yun)動(dong)(dong)部件(jian)(jian)，按給定的(de)方(fang)向做往(wang)復直(zhi)線(xian)(xian)運(yun)動(dong)(dong)。　直(zhi)線(xian)(xian)軸(zhou)承主(zhu)要(yao)用(yong)(yong)在(zai)自動(dong)(dong)化(hua)機械(xie)上比(bi)較多(duo),像直(zhi)線(xian)(xian)導軌(gui)(gui)主(zhu)要(yao)是用(yong)(yong)在(zai)精度(du)(du)要(yao)求比(bi)較高的(de)機械(xie)結構(gou)上,直(zhi)線(xian)(xian)導軌(gui)(gui)的(de)移動(dong)(dong)元(yuan)件(jian)(jian)和固定元(yuan)件(jian)(jian)之(zhi)(zhi)間不(bu)用(yong)(yong)中間介質，而用(yong)(yong)滾(gun)動(dong)(dong)鋼球(qiu)。可(ke)以理解為是一(yi)種滾(gun)動(dong)(dong)導引(yin)，是由(you)鋼珠在(zai)滑(hua)塊跟導軌(gui)(gui)之(zhi)(zhi)間無限(xian)滾(gun)動(dong)(dong)循環， 從而使負載(zai)平臺沿著導軌(gui)(gui)輕(qing)易(yi)的(de)高精度(du)(du)線(xian)(xian)性(xing)運(yun)動(dong)(dong)，并(bing)將摩擦系(xi)數降至平常傳(chuan)統滑(hua)動(dong)(dong)導引(yin)的(de)五十分之(zhi)(zhi)一(yi)，能輕(qing)易(yi)地達到(dao)很高的(de)定位精度(du)(du)。滑(hua)塊跟導軌(gui)(gui)間末(mo)制(zhi)單元(yuan)設計，使線(xian)(xian)形導軌(gui)(gui)同時承受(shou)上下左右(you)等各方(fang)向的(de)負荷(he)，回流系(xi)統及精簡化(hua)的(de)結構(gou)設計讓線(xian)(xian)性(xing)導軌(gui)(gui)有更平順且(qie)低噪(zao)音的(de)運(yun)動(dong)(dong)。

滑(hua)塊-使運動(dong)由曲(qu)線轉(zhuan)變為直(zhi)線。

直線(xian)導(dao)(dao)軌主要(yao)是用(yong)(yong)在精度(du)要(yao)求比較高的機(ji)(ji)械結構上(shang),直線(xian)導(dao)(dao)軌的移動(dong)(dong)元(yuan)件和固定元(yuan)件之間不用(yong)(yong)中間介質，而用(yong)(yong)滾(gun)動(dong)(dong)鋼(gang)球(qiu)。因為滾(gun)動(dong)(dong)鋼(gang)球(qiu)適應于高速(su)運動(dong)(dong)、摩擦系數小(xiao)、靈敏度(du)高，滿足運動(dong)(dong)部件的工(gong)作要(yao)求，被(bei)廣(guang)泛(fan)應用(yong)(yong)在自動(dong)(dong)化(hua)機(ji)(ji)械上(shang)比較多(duo),像磨床(chuang)、銑(xian)床(chuang)、車床(chuang)、檢測儀器設備、木工(gong)機(ji)(ji)械、搬運機(ji)(ji)械、傳(chuan)送(song)裝(zhuang)置、自動(dong)(dong)化(hua)機(ji)(ji)械、半導(dao)(dao)體(ti)機(ji)(ji)械、包裝(zhuang)機(ji)(ji)械、機(ji)(ji)械手(shou)臂、自動(dong)(dong)化(hua)機(ji)(ji)床(chuang)、激光行業、汽車制造、新(xin)能源等行業。