直線(xian)(xian)導軌(gui)又稱線(xian)(xian)軌(gui)、滑軌(gui)、線(xian)(xian)性導軌(gui)、線(xian)(xian)性滑軌(gui)，用于高(gao)精或高(gao)速直線(xian)(xian)往復運動(dong)場合，且可(ke)(ke)以承擔一定的扭(niu)矩(ju)，可(ke)(ke)在高(gao)負載的情(qing)況下(xia)實現(xian)高(gao)精度的直線(xian)(xian)運動(dong)。

直線(xian)(xian)導(dao)(dao)(dao)軌(gui)(gui)運(yun)(yun)動(dong)(dong)的作用(yong)是(shi)用(yong)來支撐和引(yin)導(dao)(dao)(dao)運(yun)(yun)動(dong)(dong)部件(jian)(jian)，按給(gei)定(ding)的方(fang)向(xiang)做往復(fu)直線(xian)(xian)運(yun)(yun)動(dong)(dong)。　直線(xian)(xian)軸承主要用(yong)在(zai)(zai)自(zi)動(dong)(dong)化(hua)機(ji)械上比較(jiao)多,像(xiang)直線(xian)(xian)導(dao)(dao)(dao)軌(gui)(gui)主要是(shi)用(yong)在(zai)(zai)精(jing)度要求(qiu)比較(jiao)高的機(ji)械結構上,直線(xian)(xian)導(dao)(dao)(dao)軌(gui)(gui)的移動(dong)(dong)元(yuan)件(jian)(jian)和固定(ding)元(yuan)件(jian)(jian)之間(jian)(jian)不用(yong)中間(jian)(jian)介質，而(er)(er)用(yong)滾(gun)動(dong)(dong)鋼球。可以理(li)解為是(shi)一(yi)種滾(gun)動(dong)(dong)導(dao)(dao)(dao)引(yin)，是(shi)由(you)鋼珠在(zai)(zai)滑(hua)塊跟導(dao)(dao)(dao)軌(gui)(gui)之間(jian)(jian)無(wu)限滾(gun)動(dong)(dong)循(xun)環， 從而(er)(er)使(shi)負載平臺(tai)沿(yan)著導(dao)(dao)(dao)軌(gui)(gui)輕易的高精(jing)度線(xian)(xian)性(xing)運(yun)(yun)動(dong)(dong)，并(bing)將摩擦系數降至平常傳統(tong)滑(hua)動(dong)(dong)導(dao)(dao)(dao)引(yin)的五十分之一(yi)，能輕易地(di)達(da)到很高的定(ding)位精(jing)度。滑(hua)塊跟導(dao)(dao)(dao)軌(gui)(gui)間(jian)(jian)末制單元(yuan)設計，使(shi)線(xian)(xian)形導(dao)(dao)(dao)軌(gui)(gui)同時承受上下左(zuo)右等各(ge)方(fang)向(xiang)的負荷，回流(liu)系統(tong)及(ji)精(jing)簡化(hua)的結構設計讓線(xian)(xian)性(xing)導(dao)(dao)(dao)軌(gui)(gui)有更平順且低噪音的運(yun)(yun)動(dong)(dong)。

滑塊-使(shi)運動由曲線(xian)轉變為直線(xian)。

直線導(dao)軌主要是用在精度要求比較(jiao)(jiao)高(gao)的機(ji)械(xie)(xie)(xie)結構(gou)上(shang),直線導(dao)軌的移(yi)動元(yuan)件和固定元(yuan)件之間不用中間介質，而用滾動鋼球(qiu)。因為滾動鋼球(qiu)適應于高(gao)速運動、摩擦(ca)系數小、靈敏度高(gao)，滿(man)足(zu)運動部件的工(gong)作(zuo)要求，被廣泛應用在自動化機(ji)械(xie)(xie)(xie)上(shang)比較(jiao)(jiao)多,像磨床(chuang)、銑床(chuang)、車床(chuang)、檢測(ce)儀器設備、木工(gong)機(ji)械(xie)(xie)(xie)、搬運機(ji)械(xie)(xie)(xie)、傳送裝置、自動化機(ji)械(xie)(xie)(xie)、半(ban)導(dao)體機(ji)械(xie)(xie)(xie)、包(bao)裝機(ji)械(xie)(xie)(xie)、機(ji)械(xie)(xie)(xie)手臂(bei)、自動化機(ji)床(chuang)、激光行業、汽(qi)車制造、新能(neng)源等行業。