直(zhi)線(xian)導軌又(you)稱(cheng)線(xian)軌、滑(hua)軌、線(xian)性導軌、線(xian)性滑(hua)軌，用于(yu)高精或(huo)高速直(zhi)線(xian)往復運動場(chang)合(he)，且可以承(cheng)擔一定(ding)的扭矩，可在高負載的情況下實現(xian)高精度的直(zhi)線(xian)運動。

直(zhi)線(xian)(xian)(xian)(xian)導(dao)軌(gui)(gui)運(yun)動(dong)(dong)(dong)的(de)(de)作用(yong)是用(yong)來支撐和引導(dao)運(yun)動(dong)(dong)(dong)部件(jian)，按給(gei)定(ding)的(de)(de)方(fang)向做往復直(zhi)線(xian)(xian)(xian)(xian)運(yun)動(dong)(dong)(dong)。　直(zhi)線(xian)(xian)(xian)(xian)軸承(cheng)主(zhu)要(yao)用(yong)在自動(dong)(dong)(dong)化機械上(shang)比(bi)(bi)較(jiao)多,像直(zhi)線(xian)(xian)(xian)(xian)導(dao)軌(gui)(gui)主(zhu)要(yao)是用(yong)在精度(du)要(yao)求比(bi)(bi)較(jiao)高的(de)(de)機械結(jie)構上(shang),直(zhi)線(xian)(xian)(xian)(xian)導(dao)軌(gui)(gui)的(de)(de)移動(dong)(dong)(dong)元(yuan)(yuan)件(jian)和固(gu)定(ding)元(yuan)(yuan)件(jian)之間(jian)不用(yong)中間(jian)介質，而用(yong)滾(gun)動(dong)(dong)(dong)鋼球。可(ke)以理解(jie)為是一(yi)種(zhong)滾(gun)動(dong)(dong)(dong)導(dao)引，是由鋼珠在滑(hua)塊跟導(dao)軌(gui)(gui)之間(jian)無限滾(gun)動(dong)(dong)(dong)循環， 從而使負載(zai)平(ping)臺沿著導(dao)軌(gui)(gui)輕(qing)易的(de)(de)高精度(du)線(xian)(xian)(xian)(xian)性運(yun)動(dong)(dong)(dong)，并將摩擦系(xi)數(shu)降至(zhi)平(ping)常傳統滑(hua)動(dong)(dong)(dong)導(dao)引的(de)(de)五十分之一(yi)，能輕(qing)易地達(da)到很高的(de)(de)定(ding)位精度(du)。滑(hua)塊跟導(dao)軌(gui)(gui)間(jian)末制單元(yuan)(yuan)設(she)計，使線(xian)(xian)(xian)(xian)形導(dao)軌(gui)(gui)同時承(cheng)受上(shang)下左(zuo)右等(deng)各(ge)方(fang)向的(de)(de)負荷，回流系(xi)統及(ji)精簡化的(de)(de)結(jie)構設(she)計讓線(xian)(xian)(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)(dong)。

滑塊-使運動由曲(qu)線轉變為直線。

直線(xian)(xian)導軌主要(yao)是(shi)用在精(jing)度要(yao)求比較高(gao)(gao)的機(ji)械(xie)結(jie)構上(shang),直線(xian)(xian)導軌的移動(dong)(dong)(dong)元件和(he)固定元件之間不(bu)用中間介(jie)質，而用滾動(dong)(dong)(dong)鋼球。因為滾動(dong)(dong)(dong)鋼球適應(ying)于高(gao)(gao)速運(yun)動(dong)(dong)(dong)、摩擦系數小(xiao)、靈敏(min)度高(gao)(gao)，滿足運(yun)動(dong)(dong)(dong)部(bu)件的工作(zuo)要(yao)求，被廣(guang)泛(fan)應(ying)用在自動(dong)(dong)(dong)化機(ji)械(xie)上(shang)比較多,像磨床(chuang)、銑床(chuang)、車床(chuang)、檢(jian)測(ce)儀器設備、木(mu)工機(ji)械(xie)、搬運(yun)機(ji)械(xie)、傳送裝置、自動(dong)(dong)(dong)化機(ji)械(xie)、半導體機(ji)械(xie)、包裝機(ji)械(xie)、機(ji)械(xie)手臂(bei)、自動(dong)(dong)(dong)化機(ji)床(chuang)、激光行(xing)業、汽(qi)車制造、新能源等行(xing)業。