直線(xian)導軌(gui)又(you)稱線(xian)軌(gui)、滑(hua)軌(gui)、線(xian)性(xing)導軌(gui)、線(xian)性(xing)滑(hua)軌(gui)，用于(yu)高精或高速(su)直線(xian)往(wang)復運動場合，且(qie)可以承擔一定的(de)扭(niu)矩，可在高負載(zai)的(de)情況(kuang)下實現高精度的(de)直線(xian)運動。

直線(xian)(xian)導(dao)(dao)(dao)軌運(yun)動(dong)(dong)(dong)的(de)(de)作用(yong)是用(yong)來支(zhi)撐和引(yin)導(dao)(dao)(dao)運(yun)動(dong)(dong)(dong)部件(jian)，按給定的(de)(de)方向(xiang)做往(wang)復直線(xian)(xian)運(yun)動(dong)(dong)(dong)。　直線(xian)(xian)軸承(cheng)主要(yao)用(yong)在(zai)(zai)自動(dong)(dong)(dong)化機(ji)械上(shang)比較多(duo),像直線(xian)(xian)導(dao)(dao)(dao)軌主要(yao)是用(yong)在(zai)(zai)精(jing)度要(yao)求比較高的(de)(de)機(ji)械結(jie)構上(shang),直線(xian)(xian)導(dao)(dao)(dao)軌的(de)(de)移動(dong)(dong)(dong)元件(jian)和固(gu)定元件(jian)之間(jian)不用(yong)中間(jian)介質，而(er)用(yong)滾動(dong)(dong)(dong)鋼球。可以理解為是一種滾動(dong)(dong)(dong)導(dao)(dao)(dao)引(yin)，是由鋼珠在(zai)(zai)滑(hua)塊(kuai)跟(gen)導(dao)(dao)(dao)軌之間(jian)無限滾動(dong)(dong)(dong)循環， 從而(er)使負載(zai)平臺沿著導(dao)(dao)(dao)軌輕(qing)易(yi)的(de)(de)高精(jing)度線(xian)(xian)性運(yun)動(dong)(dong)(dong)，并將(jiang)摩擦系(xi)數降(jiang)至(zhi)平常傳統滑(hua)動(dong)(dong)(dong)導(dao)(dao)(dao)引(yin)的(de)(de)五十分(fen)之一，能輕(qing)易(yi)地(di)達到很高的(de)(de)定位精(jing)度。滑(hua)塊(kuai)跟(gen)導(dao)(dao)(dao)軌間(jian)末制單(dan)元設(she)計，使線(xian)(xian)形導(dao)(dao)(dao)軌同時承(cheng)受上(shang)下左(zuo)右(you)等各方向(xiang)的(de)(de)負荷，回流(liu)系(xi)統及精(jing)簡化的(de)(de)結(jie)構設(she)計讓(rang)線(xian)(xian)性導(dao)(dao)(dao)軌有更平順且低噪音的(de)(de)運(yun)動(dong)(dong)(dong)。

滑塊-使運動由曲線(xian)轉變(bian)為直(zhi)線(xian)。

直線(xian)導軌主要是(shi)用在精度要求比較高的(de)機(ji)(ji)械(xie)(xie)(xie)(xie)結構上(shang),直線(xian)導軌的(de)移動(dong)元件和固定元件之(zhi)間不用中間介質，而用滾(gun)動(dong)鋼球。因為滾(gun)動(dong)鋼球適應于高速(su)運(yun)動(dong)、摩(mo)擦(ca)系(xi)數小(xiao)、靈敏度高，滿足運(yun)動(dong)部件的(de)工(gong)作(zuo)要求，被廣泛應用在自(zi)動(dong)化機(ji)(ji)械(xie)(xie)(xie)(xie)上(shang)比較多,像磨床、銑床、車床、檢(jian)測儀器設(she)備(bei)、木工(gong)機(ji)(ji)械(xie)(xie)(xie)(xie)、搬運(yun)機(ji)(ji)械(xie)(xie)(xie)(xie)、傳送裝置、自(zi)動(dong)化機(ji)(ji)械(xie)(xie)(xie)(xie)、半導體機(ji)(ji)械(xie)(xie)(xie)(xie)、包裝機(ji)(ji)械(xie)(xie)(xie)(xie)、機(ji)(ji)械(xie)(xie)(xie)(xie)手臂、自(zi)動(dong)化機(ji)(ji)床、激光行(xing)(xing)業、汽車制造、新能源等行(xing)(xing)業。