直線導(dao)軌(gui)又稱(cheng)線軌(gui)、滑軌(gui)、線性(xing)導(dao)軌(gui)、線性(xing)滑軌(gui)，用于高(gao)精或高(gao)速直線往(wang)復運動場合，且可(ke)以(yi)承擔一定的扭矩，可(ke)在高(gao)負載的情況下實現高(gao)精度的直線運動。

直(zhi)(zhi)線(xian)導(dao)(dao)(dao)軌(gui)運(yun)(yun)動的作用(yong)(yong)是(shi)用(yong)(yong)來(lai)支撐和引導(dao)(dao)(dao)運(yun)(yun)動部(bu)件，按給定(ding)的方向做往(wang)復直(zhi)(zhi)線(xian)運(yun)(yun)動。　直(zhi)(zhi)線(xian)軸(zhou)承主要用(yong)(yong)在自(zi)動化機械(xie)上(shang)比(bi)較多,像直(zhi)(zhi)線(xian)導(dao)(dao)(dao)軌(gui)主要是(shi)用(yong)(yong)在精(jing)度要求比(bi)較高的機械(xie)結構(gou)上(shang),直(zhi)(zhi)線(xian)導(dao)(dao)(dao)軌(gui)的移動元(yuan)(yuan)件和固(gu)定(ding)元(yuan)(yuan)件之間不用(yong)(yong)中間介(jie)質，而用(yong)(yong)滾動鋼球。可以理解為是(shi)一種滾動導(dao)(dao)(dao)引，是(shi)由鋼珠在滑(hua)(hua)塊跟導(dao)(dao)(dao)軌(gui)之間無限滾動循環， 從而使負(fu)(fu)載平(ping)臺沿(yan)著導(dao)(dao)(dao)軌(gui)輕(qing)易的高精(jing)度線(xian)性(xing)運(yun)(yun)動，并(bing)將摩擦系數(shu)降至平(ping)常傳統(tong)滑(hua)(hua)動導(dao)(dao)(dao)引的五十(shi)分(fen)之一，能輕(qing)易地達到很高的定(ding)位精(jing)度。滑(hua)(hua)塊跟導(dao)(dao)(dao)軌(gui)間末制單元(yuan)(yuan)設計，使線(xian)形導(dao)(dao)(dao)軌(gui)同時承受上(shang)下左右等(deng)各(ge)方向的負(fu)(fu)荷，回(hui)流系統(tong)及精(jing)簡化的結構(gou)設計讓(rang)線(xian)性(xing)導(dao)(dao)(dao)軌(gui)有(you)更平(ping)順且低噪音(yin)的運(yun)(yun)動。

滑塊-使(shi)運(yun)動由曲(qu)線(xian)轉(zhuan)變為直線(xian)。

直線導軌主要是(shi)用(yong)(yong)(yong)在(zai)(zai)精(jing)度要求比較(jiao)高(gao)的機(ji)(ji)械(xie)結構上,直線導軌的移(yi)動(dong)(dong)(dong)(dong)元(yuan)件和(he)固定元(yuan)件之間不用(yong)(yong)(yong)中間介質，而用(yong)(yong)(yong)滾動(dong)(dong)(dong)(dong)鋼球(qiu)。因為滾動(dong)(dong)(dong)(dong)鋼球(qiu)適(shi)應于高(gao)速運(yun)動(dong)(dong)(dong)(dong)、摩(mo)擦系數(shu)小、靈(ling)敏度高(gao)，滿足(zu)運(yun)動(dong)(dong)(dong)(dong)部件的工作要求，被廣泛應用(yong)(yong)(yong)在(zai)(zai)自動(dong)(dong)(dong)(dong)化(hua)機(ji)(ji)械(xie)上比較(jiao)多,像磨床(chuang)、銑床(chuang)、車床(chuang)、檢測儀器設備、木工機(ji)(ji)械(xie)、搬運(yun)機(ji)(ji)械(xie)、傳送(song)裝(zhuang)置、自動(dong)(dong)(dong)(dong)化(hua)機(ji)(ji)械(xie)、半導體機(ji)(ji)械(xie)、包裝(zhuang)機(ji)(ji)械(xie)、機(ji)(ji)械(xie)手(shou)臂、自動(dong)(dong)(dong)(dong)化(hua)機(ji)(ji)床(chuang)、激(ji)光行(xing)業、汽車制造、新能源(yuan)等行(xing)業。