直線導軌又稱(cheng)線軌、滑軌、線性(xing)導軌、線性(xing)滑軌，用于高(gao)精或高(gao)速直線往復運(yun)動場合，且(qie)可以(yi)承(cheng)擔一定(ding)的扭矩，可在(zai)高(gao)負載的情(qing)況下實(shi)現高(gao)精度(du)的直線運(yun)動。

直(zhi)線(xian)導(dao)(dao)(dao)(dao)軌(gui)(gui)運(yun)動(dong)(dong)的(de)(de)(de)作用(yong)是用(yong)來支(zhi)撐(cheng)和引(yin)導(dao)(dao)(dao)(dao)運(yun)動(dong)(dong)部件，按給定的(de)(de)(de)方(fang)向(xiang)做往復直(zhi)線(xian)運(yun)動(dong)(dong)。　直(zhi)線(xian)軸承主要用(yong)在(zai)自(zi)動(dong)(dong)化機械上(shang)比(bi)(bi)較(jiao)多,像直(zhi)線(xian)導(dao)(dao)(dao)(dao)軌(gui)(gui)主要是用(yong)在(zai)精(jing)度要求比(bi)(bi)較(jiao)高(gao)的(de)(de)(de)機械結(jie)構上(shang),直(zhi)線(xian)導(dao)(dao)(dao)(dao)軌(gui)(gui)的(de)(de)(de)移(yi)動(dong)(dong)元件和固定元件之間(jian)不(bu)用(yong)中間(jian)介質(zhi)，而用(yong)滾動(dong)(dong)鋼球。可以理解為(wei)是一種滾動(dong)(dong)導(dao)(dao)(dao)(dao)引(yin)，是由鋼珠在(zai)滑塊(kuai)跟導(dao)(dao)(dao)(dao)軌(gui)(gui)之間(jian)無限滾動(dong)(dong)循環， 從而使負載平臺(tai)沿(yan)著導(dao)(dao)(dao)(dao)軌(gui)(gui)輕(qing)易的(de)(de)(de)高(gao)精(jing)度線(xian)性(xing)運(yun)動(dong)(dong)，并將(jiang)摩(mo)擦系(xi)數(shu)降至(zhi)平常傳統(tong)(tong)滑動(dong)(dong)導(dao)(dao)(dao)(dao)引(yin)的(de)(de)(de)五十分之一，能輕(qing)易地達到很高(gao)的(de)(de)(de)定位精(jing)度。滑塊(kuai)跟導(dao)(dao)(dao)(dao)軌(gui)(gui)間(jian)末制單元設計(ji)，使線(xian)形導(dao)(dao)(dao)(dao)軌(gui)(gui)同時承受上(shang)下左(zuo)右(you)等各方(fang)向(xiang)的(de)(de)(de)負荷，回流系(xi)統(tong)(tong)及精(jing)簡化的(de)(de)(de)結(jie)構設計(ji)讓線(xian)性(xing)導(dao)(dao)(dao)(dao)軌(gui)(gui)有更(geng)平順且(qie)低噪音的(de)(de)(de)運(yun)動(dong)(dong)。

滑(hua)塊-使運動(dong)由曲(qu)線(xian)轉變為直線(xian)。

直(zhi)線導(dao)軌(gui)主要是用在精度(du)要求比較高(gao)的機(ji)(ji)(ji)械(xie)結構上,直(zhi)線導(dao)軌(gui)的移動(dong)(dong)(dong)元件和固定元件之間不用中間介質，而(er)用滾(gun)動(dong)(dong)(dong)鋼球(qiu)。因為(wei)滾(gun)動(dong)(dong)(dong)鋼球(qiu)適應于高(gao)速運(yun)動(dong)(dong)(dong)、摩擦(ca)系數小、靈敏(min)度(du)高(gao)，滿(man)足(zu)運(yun)動(dong)(dong)(dong)部(bu)件的工(gong)作(zuo)要求，被廣(guang)泛應用在自動(dong)(dong)(dong)化(hua)(hua)機(ji)(ji)(ji)械(xie)上比較多(duo),像磨床(chuang)、銑(xian)床(chuang)、車(che)床(chuang)、檢測儀器設備、木工(gong)機(ji)(ji)(ji)械(xie)、搬運(yun)機(ji)(ji)(ji)械(xie)、傳送裝(zhuang)置(zhi)、自動(dong)(dong)(dong)化(hua)(hua)機(ji)(ji)(ji)械(xie)、半導(dao)體機(ji)(ji)(ji)械(xie)、包裝(zhuang)機(ji)(ji)(ji)械(xie)、機(ji)(ji)(ji)械(xie)手臂、自動(dong)(dong)(dong)化(hua)(hua)機(ji)(ji)(ji)床(chuang)、激光行(xing)業、汽車(che)制造、新能源等行(xing)業。