直線(xian)導軌(gui)又稱線(xian)軌(gui)、滑軌(gui)、線(xian)性導軌(gui)、線(xian)性滑軌(gui)，用于高(gao)精或高(gao)速直線(xian)往復(fu)運動(dong)場合，且可以承擔一定(ding)的扭矩，可在高(gao)負載的情況下實現(xian)高(gao)精度的直線(xian)運動(dong)。

直(zhi)(zhi)線(xian)導(dao)(dao)軌(gui)(gui)運(yun)(yun)動(dong)(dong)(dong)(dong)(dong)的(de)(de)作用(yong)(yong)是(shi)用(yong)(yong)來支撐和引(yin)導(dao)(dao)運(yun)(yun)動(dong)(dong)(dong)(dong)(dong)部件，按給定的(de)(de)方向做往復直(zhi)(zhi)線(xian)運(yun)(yun)動(dong)(dong)(dong)(dong)(dong)。　直(zhi)(zhi)線(xian)軸承(cheng)主要用(yong)(yong)在(zai)(zai)自動(dong)(dong)(dong)(dong)(dong)化機械(xie)上比較多,像直(zhi)(zhi)線(xian)導(dao)(dao)軌(gui)(gui)主要是(shi)用(yong)(yong)在(zai)(zai)精(jing)(jing)(jing)度(du)(du)要求比較高的(de)(de)機械(xie)結構(gou)(gou)上,直(zhi)(zhi)線(xian)導(dao)(dao)軌(gui)(gui)的(de)(de)移動(dong)(dong)(dong)(dong)(dong)元(yuan)件和固定元(yuan)件之間(jian)不(bu)用(yong)(yong)中間(jian)介質，而(er)用(yong)(yong)滾動(dong)(dong)(dong)(dong)(dong)鋼(gang)(gang)球。可以理解為是(shi)一(yi)種(zhong)滾動(dong)(dong)(dong)(dong)(dong)導(dao)(dao)引(yin)，是(shi)由鋼(gang)(gang)珠在(zai)(zai)滑(hua)塊跟導(dao)(dao)軌(gui)(gui)之間(jian)無限滾動(dong)(dong)(dong)(dong)(dong)循環， 從而(er)使負(fu)載平(ping)臺沿著導(dao)(dao)軌(gui)(gui)輕易的(de)(de)高精(jing)(jing)(jing)度(du)(du)線(xian)性運(yun)(yun)動(dong)(dong)(dong)(dong)(dong)，并將摩擦系數降至平(ping)常傳統滑(hua)動(dong)(dong)(dong)(dong)(dong)導(dao)(dao)引(yin)的(de)(de)五十分之一(yi)，能輕易地(di)達到(dao)很高的(de)(de)定位精(jing)(jing)(jing)度(du)(du)。滑(hua)塊跟導(dao)(dao)軌(gui)(gui)間(jian)末制單元(yuan)設(she)計，使線(xian)形導(dao)(dao)軌(gui)(gui)同時承(cheng)受上下左(zuo)右等各(ge)方向的(de)(de)負(fu)荷，回(hui)流(liu)系統及(ji)精(jing)(jing)(jing)簡化的(de)(de)結構(gou)(gou)設(she)計讓線(xian)性導(dao)(dao)軌(gui)(gui)有更平(ping)順(shun)且低噪音的(de)(de)運(yun)(yun)動(dong)(dong)(dong)(dong)(dong)。

滑塊-使運(yun)動(dong)由曲線(xian)轉(zhuan)變為直(zhi)線(xian)。

直(zhi)線導軌主(zhu)要是用(yong)在(zai)精度(du)要求比較(jiao)高(gao)的(de)機(ji)(ji)(ji)(ji)械(xie)(xie)結構上(shang),直(zhi)線導軌的(de)移動(dong)(dong)元(yuan)件(jian)和(he)固定(ding)元(yuan)件(jian)之間不(bu)用(yong)中間介質，而(er)用(yong)滾(gun)動(dong)(dong)鋼球(qiu)。因(yin)為滾(gun)動(dong)(dong)鋼球(qiu)適應(ying)于高(gao)速運(yun)動(dong)(dong)、摩擦系(xi)數小、靈敏(min)度(du)高(gao)，滿足(zu)運(yun)動(dong)(dong)部(bu)件(jian)的(de)工作要求，被廣泛應(ying)用(yong)在(zai)自動(dong)(dong)化機(ji)(ji)(ji)(ji)械(xie)(xie)上(shang)比較(jiao)多,像磨床(chuang)、銑床(chuang)、車床(chuang)、檢測(ce)儀器設備、木工機(ji)(ji)(ji)(ji)械(xie)(xie)、搬運(yun)機(ji)(ji)(ji)(ji)械(xie)(xie)、傳(chuan)送(song)裝置、自動(dong)(dong)化機(ji)(ji)(ji)(ji)械(xie)(xie)、半導體機(ji)(ji)(ji)(ji)械(xie)(xie)、包裝機(ji)(ji)(ji)(ji)械(xie)(xie)、機(ji)(ji)(ji)(ji)械(xie)(xie)手臂、自動(dong)(dong)化機(ji)(ji)(ji)(ji)床(chuang)、激光行業(ye)、汽車制造、新能源(yuan)等行業(ye)。