直(zhi)(zhi)線(xian)(xian)導(dao)軌又稱線(xian)(xian)軌、滑(hua)軌、線(xian)(xian)性導(dao)軌、線(xian)(xian)性滑(hua)軌，用于高(gao)(gao)精或高(gao)(gao)速直(zhi)(zhi)線(xian)(xian)往復運動(dong)場(chang)合，且可(ke)以承擔一定的(de)扭矩，可(ke)在(zai)高(gao)(gao)負載的(de)情況下(xia)實現高(gao)(gao)精度的(de)直(zhi)(zhi)線(xian)(xian)運動(dong)。

直線(xian)導(dao)(dao)(dao)(dao)(dao)軌(gui)(gui)(gui)運(yun)(yun)動(dong)(dong)(dong)(dong)(dong)的(de)(de)作用(yong)(yong)(yong)是(shi)用(yong)(yong)(yong)來支撐(cheng)和(he)引導(dao)(dao)(dao)(dao)(dao)運(yun)(yun)動(dong)(dong)(dong)(dong)(dong)部件(jian)，按給定(ding)的(de)(de)方(fang)向做往復直線(xian)運(yun)(yun)動(dong)(dong)(dong)(dong)(dong)。　直線(xian)軸承主(zhu)要用(yong)(yong)(yong)在(zai)自動(dong)(dong)(dong)(dong)(dong)化機械上比較(jiao)多,像(xiang)直線(xian)導(dao)(dao)(dao)(dao)(dao)軌(gui)(gui)(gui)主(zhu)要是(shi)用(yong)(yong)(yong)在(zai)精(jing)(jing)度(du)要求比較(jiao)高的(de)(de)機械結(jie)構(gou)上,直線(xian)導(dao)(dao)(dao)(dao)(dao)軌(gui)(gui)(gui)的(de)(de)移動(dong)(dong)(dong)(dong)(dong)元件(jian)和(he)固定(ding)元件(jian)之間(jian)不用(yong)(yong)(yong)中間(jian)介質，而(er)用(yong)(yong)(yong)滾(gun)動(dong)(dong)(dong)(dong)(dong)鋼球(qiu)。可以理(li)解為是(shi)一(yi)種滾(gun)動(dong)(dong)(dong)(dong)(dong)導(dao)(dao)(dao)(dao)(dao)引，是(shi)由鋼珠(zhu)在(zai)滑(hua)塊(kuai)跟(gen)導(dao)(dao)(dao)(dao)(dao)軌(gui)(gui)(gui)之間(jian)無限滾(gun)動(dong)(dong)(dong)(dong)(dong)循(xun)環， 從(cong)而(er)使負載(zai)平臺沿(yan)著(zhu)導(dao)(dao)(dao)(dao)(dao)軌(gui)(gui)(gui)輕易的(de)(de)高精(jing)(jing)度(du)線(xian)性運(yun)(yun)動(dong)(dong)(dong)(dong)(dong)，并將(jiang)摩(mo)擦系數降至平常傳統(tong)滑(hua)動(dong)(dong)(dong)(dong)(dong)導(dao)(dao)(dao)(dao)(dao)引的(de)(de)五十(shi)分之一(yi)，能輕易地達到很高的(de)(de)定(ding)位精(jing)(jing)度(du)。滑(hua)塊(kuai)跟(gen)導(dao)(dao)(dao)(dao)(dao)軌(gui)(gui)(gui)間(jian)末制單(dan)元設計，使線(xian)形導(dao)(dao)(dao)(dao)(dao)軌(gui)(gui)(gui)同時承受上下左右(you)等各方(fang)向的(de)(de)負荷(he)，回流系統(tong)及精(jing)(jing)簡化的(de)(de)結(jie)構(gou)設計讓線(xian)性導(dao)(dao)(dao)(dao)(dao)軌(gui)(gui)(gui)有更平順且低(di)噪音的(de)(de)運(yun)(yun)動(dong)(dong)(dong)(dong)(dong)。

滑塊-使運動由曲(qu)線轉變為直線。

直線導(dao)(dao)軌主要是用在(zai)精度要求(qiu)比較(jiao)高的機(ji)械(xie)結構上,直線導(dao)(dao)軌的移(yi)動(dong)(dong)元件和固定(ding)元件之間不用中(zhong)間介質(zhi)，而用滾動(dong)(dong)鋼(gang)球。因為(wei)滾動(dong)(dong)鋼(gang)球適(shi)應(ying)于高速運動(dong)(dong)、摩擦(ca)系數小(xiao)、靈敏度高，滿足運動(dong)(dong)部(bu)件的工作要求(qiu)，被廣(guang)泛應(ying)用在(zai)自(zi)動(dong)(dong)化(hua)機(ji)械(xie)上比較(jiao)多,像磨床、銑床、車床、檢(jian)測儀器設備、木工機(ji)械(xie)、搬運機(ji)械(xie)、傳送裝(zhuang)置(zhi)、自(zi)動(dong)(dong)化(hua)機(ji)械(xie)、半導(dao)(dao)體機(ji)械(xie)、包裝(zhuang)機(ji)械(xie)、機(ji)械(xie)手臂、自(zi)動(dong)(dong)化(hua)機(ji)床、激光行業、汽車制(zhi)造、新能源等行業。