直線(xian)導軌又(you)稱(cheng)線(xian)軌、滑軌、線(xian)性(xing)導軌、線(xian)性(xing)滑軌，用于高精或高速直線(xian)往復運(yun)動(dong)場合(he)，且可以承擔一定(ding)的扭矩，可在(zai)高負(fu)載的情況下實現高精度的直線(xian)運(yun)動(dong)。

直(zhi)線(xian)(xian)導(dao)軌(gui)(gui)運(yun)動(dong)(dong)的(de)(de)作用(yong)是用(yong)來支撐和引(yin)導(dao)運(yun)動(dong)(dong)部(bu)件(jian)(jian)，按給定(ding)的(de)(de)方(fang)向做往復直(zhi)線(xian)(xian)運(yun)動(dong)(dong)。　直(zhi)線(xian)(xian)軸承主(zhu)要用(yong)在自動(dong)(dong)化(hua)機(ji)械上(shang)比較多,像直(zhi)線(xian)(xian)導(dao)軌(gui)(gui)主(zhu)要是用(yong)在精(jing)(jing)度要求比較高(gao)(gao)的(de)(de)機(ji)械結構(gou)上(shang),直(zhi)線(xian)(xian)導(dao)軌(gui)(gui)的(de)(de)移動(dong)(dong)元(yuan)(yuan)件(jian)(jian)和固定(ding)元(yuan)(yuan)件(jian)(jian)之間不用(yong)中間介質，而(er)用(yong)滾(gun)(gun)動(dong)(dong)鋼球。可以理解為是一(yi)種滾(gun)(gun)動(dong)(dong)導(dao)引(yin)，是由鋼珠在滑(hua)(hua)塊(kuai)跟導(dao)軌(gui)(gui)之間無限滾(gun)(gun)動(dong)(dong)循環(huan)， 從(cong)而(er)使負載平(ping)臺沿著導(dao)軌(gui)(gui)輕(qing)易的(de)(de)高(gao)(gao)精(jing)(jing)度線(xian)(xian)性運(yun)動(dong)(dong)，并將摩(mo)擦系數(shu)降至平(ping)常(chang)傳統滑(hua)(hua)動(dong)(dong)導(dao)引(yin)的(de)(de)五十分之一(yi)，能(neng)輕(qing)易地達到很高(gao)(gao)的(de)(de)定(ding)位精(jing)(jing)度。滑(hua)(hua)塊(kuai)跟導(dao)軌(gui)(gui)間末制單元(yuan)(yuan)設計，使線(xian)(xian)形導(dao)軌(gui)(gui)同(tong)時承受(shou)上(shang)下左右等各方(fang)向的(de)(de)負荷，回流系統及精(jing)(jing)簡化(hua)的(de)(de)結構(gou)設計讓線(xian)(xian)性導(dao)軌(gui)(gui)有更平(ping)順且低噪音的(de)(de)運(yun)動(dong)(dong)。

滑塊-使(shi)運動由曲線轉變為直線。

直線導軌主要(yao)是用(yong)在精度要(yao)求比較高(gao)的(de)(de)機(ji)(ji)(ji)(ji)械結構上(shang),直線導軌的(de)(de)移動(dong)元(yuan)件(jian)(jian)和固定元(yuan)件(jian)(jian)之(zhi)間不用(yong)中(zhong)間介質，而用(yong)滾動(dong)鋼球。因(yin)為滾動(dong)鋼球適應(ying)于(yu)高(gao)速(su)運(yun)動(dong)、摩擦系(xi)數小(xiao)、靈敏度高(gao)，滿(man)足(zu)運(yun)動(dong)部件(jian)(jian)的(de)(de)工(gong)作要(yao)求，被廣(guang)泛(fan)應(ying)用(yong)在自(zi)(zi)動(dong)化(hua)機(ji)(ji)(ji)(ji)械上(shang)比較多(duo),像磨床(chuang)、銑床(chuang)、車床(chuang)、檢測儀器設備(bei)、木工(gong)機(ji)(ji)(ji)(ji)械、搬運(yun)機(ji)(ji)(ji)(ji)械、傳送裝置、自(zi)(zi)動(dong)化(hua)機(ji)(ji)(ji)(ji)械、半導體機(ji)(ji)(ji)(ji)械、包裝機(ji)(ji)(ji)(ji)械、機(ji)(ji)(ji)(ji)械手臂、自(zi)(zi)動(dong)化(hua)機(ji)(ji)(ji)(ji)床(chuang)、激光(guang)行業(ye)(ye)、汽車制造(zao)、新(xin)能源等(deng)行業(ye)(ye)。