直(zhi)線(xian)導軌(gui)又稱(cheng)線(xian)軌(gui)、滑軌(gui)、線(xian)性導軌(gui)、線(xian)性滑軌(gui)，用于高(gao)(gao)精(jing)或高(gao)(gao)速直(zhi)線(xian)往復運動場(chang)合，且可以(yi)承(cheng)擔一定的(de)(de)扭矩，可在高(gao)(gao)負載的(de)(de)情況下實(shi)現高(gao)(gao)精(jing)度的(de)(de)直(zhi)線(xian)運動。

直(zhi)線(xian)(xian)(xian)(xian)導(dao)軌運(yun)(yun)(yun)動(dong)的(de)(de)作用是(shi)用來支撐和引(yin)(yin)導(dao)運(yun)(yun)(yun)動(dong)部件，按給定(ding)的(de)(de)方向(xiang)做往復直(zhi)線(xian)(xian)(xian)(xian)運(yun)(yun)(yun)動(dong)。　直(zhi)線(xian)(xian)(xian)(xian)軸承主(zhu)(zhu)要用在(zai)自動(dong)化機械上比較多(duo),像直(zhi)線(xian)(xian)(xian)(xian)導(dao)軌主(zhu)(zhu)要是(shi)用在(zai)精度(du)要求(qiu)比較高的(de)(de)機械結構(gou)上,直(zhi)線(xian)(xian)(xian)(xian)導(dao)軌的(de)(de)移動(dong)元(yuan)件和固定(ding)元(yuan)件之間(jian)不用中間(jian)介質，而用滾動(dong)鋼(gang)球。可以(yi)理解為是(shi)一種滾動(dong)導(dao)引(yin)(yin)，是(shi)由鋼(gang)珠在(zai)滑塊跟導(dao)軌之間(jian)無限(xian)滾動(dong)循環(huan)， 從(cong)而使負(fu)載平(ping)臺沿著導(dao)軌輕(qing)易(yi)的(de)(de)高精度(du)線(xian)(xian)(xian)(xian)性(xing)運(yun)(yun)(yun)動(dong)，并將摩擦系數降至平(ping)常傳統滑動(dong)導(dao)引(yin)(yin)的(de)(de)五十(shi)分之一，能(neng)輕(qing)易(yi)地達到很高的(de)(de)定(ding)位精度(du)。滑塊跟導(dao)軌間(jian)末制單元(yuan)設(she)計(ji)，使線(xian)(xian)(xian)(xian)形導(dao)軌同(tong)時承受上下左(zuo)右等各(ge)方向(xiang)的(de)(de)負(fu)荷，回流(liu)系統及精簡化的(de)(de)結構(gou)設(she)計(ji)讓線(xian)(xian)(xian)(xian)性(xing)導(dao)軌有更(geng)平(ping)順且低(di)噪(zao)音的(de)(de)運(yun)(yun)(yun)動(dong)。

滑塊-使運動(dong)由曲線轉變(bian)為直線。

直(zhi)線(xian)導(dao)(dao)軌主(zhu)要是用(yong)(yong)在精度要求比較高(gao)的(de)機(ji)(ji)(ji)(ji)械(xie)(xie)結(jie)構上,直(zhi)線(xian)導(dao)(dao)軌的(de)移動元件(jian)(jian)和(he)固定元件(jian)(jian)之間不用(yong)(yong)中間介質，而用(yong)(yong)滾動鋼球(qiu)。因為(wei)滾動鋼球(qiu)適應于高(gao)速運(yun)動、摩擦系數小、靈(ling)敏度高(gao)，滿足運(yun)動部(bu)件(jian)(jian)的(de)工(gong)(gong)作要求，被廣泛應用(yong)(yong)在自(zi)動化(hua)機(ji)(ji)(ji)(ji)械(xie)(xie)上比較多,像磨床、銑(xian)床、車(che)床、檢測儀器設(she)備(bei)、木(mu)工(gong)(gong)機(ji)(ji)(ji)(ji)械(xie)(xie)、搬運(yun)機(ji)(ji)(ji)(ji)械(xie)(xie)、傳送裝置、自(zi)動化(hua)機(ji)(ji)(ji)(ji)械(xie)(xie)、半(ban)導(dao)(dao)體機(ji)(ji)(ji)(ji)械(xie)(xie)、包(bao)裝機(ji)(ji)(ji)(ji)械(xie)(xie)、機(ji)(ji)(ji)(ji)械(xie)(xie)手臂、自(zi)動化(hua)機(ji)(ji)(ji)(ji)床、激光行業(ye)、汽車(che)制造、新能源等行業(ye)。