直(zhi)(zhi)(zhi)線(xian)(xian)導軌又稱線(xian)(xian)軌、滑軌、線(xian)(xian)性導軌、線(xian)(xian)性滑軌，用于高(gao)精或高(gao)速直(zhi)(zhi)(zhi)線(xian)(xian)往復運動(dong)場合，且可以承擔(dan)一定的(de)扭矩(ju)，可在高(gao)負載(zai)的(de)情況下實現(xian)高(gao)精度的(de)直(zhi)(zhi)(zhi)線(xian)(xian)運動(dong)。

直(zhi)(zhi)線(xian)(xian)(xian)導(dao)(dao)軌(gui)運動(dong)(dong)的(de)作(zuo)用是用來支撐(cheng)和引導(dao)(dao)運動(dong)(dong)部件，按(an)給定的(de)方向(xiang)做往復直(zhi)(zhi)線(xian)(xian)(xian)運動(dong)(dong)。　直(zhi)(zhi)線(xian)(xian)(xian)軸承主要(yao)用在自動(dong)(dong)化(hua)機(ji)械上(shang)比(bi)較多,像直(zhi)(zhi)線(xian)(xian)(xian)導(dao)(dao)軌(gui)主要(yao)是用在精(jing)度要(yao)求(qiu)比(bi)較高的(de)機(ji)械結(jie)構上(shang),直(zhi)(zhi)線(xian)(xian)(xian)導(dao)(dao)軌(gui)的(de)移(yi)動(dong)(dong)元件和固定元件之間不用中間介質，而用滾(gun)動(dong)(dong)鋼球。可以理解為是一(yi)種(zhong)滾(gun)動(dong)(dong)導(dao)(dao)引，是由鋼珠在滑(hua)塊跟導(dao)(dao)軌(gui)之間無限滾(gun)動(dong)(dong)循環， 從而使負載(zai)平(ping)(ping)(ping)臺(tai)沿著(zhu)導(dao)(dao)軌(gui)輕(qing)易(yi)的(de)高精(jing)度線(xian)(xian)(xian)性(xing)運動(dong)(dong)，并將摩擦系(xi)數降至(zhi)平(ping)(ping)(ping)常傳統滑(hua)動(dong)(dong)導(dao)(dao)引的(de)五(wu)十分之一(yi)，能輕(qing)易(yi)地達到很高的(de)定位(wei)精(jing)度。滑(hua)塊跟導(dao)(dao)軌(gui)間末制(zhi)單(dan)元設(she)計(ji)，使線(xian)(xian)(xian)形導(dao)(dao)軌(gui)同時(shi)承受上(shang)下左右等各方向(xiang)的(de)負荷，回流(liu)系(xi)統及精(jing)簡化(hua)的(de)結(jie)構設(she)計(ji)讓線(xian)(xian)(xian)性(xing)導(dao)(dao)軌(gui)有更平(ping)(ping)(ping)順且低噪(zao)音的(de)運動(dong)(dong)。

滑塊-使(shi)運動由曲(qu)線轉變為(wei)直(zhi)線。

直(zhi)線導(dao)(dao)軌(gui)(gui)主要(yao)是用(yong)在精度要(yao)求(qiu)比較高的機(ji)械(xie)結構上(shang),直(zhi)線導(dao)(dao)軌(gui)(gui)的移動(dong)元(yuan)件和固定元(yuan)件之間(jian)(jian)不用(yong)中間(jian)(jian)介質，而用(yong)滾動(dong)鋼球。因為滾動(dong)鋼球適(shi)應(ying)于(yu)高速(su)運(yun)動(dong)、摩擦系數小、靈敏度高，滿足(zu)運(yun)動(dong)部件的工作要(yao)求(qiu)，被(bei)廣泛應(ying)用(yong)在自(zi)(zi)動(dong)化機(ji)械(xie)上(shang)比較多(duo),像磨床(chuang)、銑床(chuang)、車(che)床(chuang)、檢測儀器設備、木工機(ji)械(xie)、搬運(yun)機(ji)械(xie)、傳送裝置(zhi)、自(zi)(zi)動(dong)化機(ji)械(xie)、半導(dao)(dao)體機(ji)械(xie)、包裝機(ji)械(xie)、機(ji)械(xie)手(shou)臂、自(zi)(zi)動(dong)化機(ji)床(chuang)、激(ji)光行業、汽車(che)制造、新能源等行業。