直線(xian)(xian)導(dao)軌(gui)(gui)又稱(cheng)線(xian)(xian)軌(gui)(gui)、滑軌(gui)(gui)、線(xian)(xian)性(xing)導(dao)軌(gui)(gui)、線(xian)(xian)性(xing)滑軌(gui)(gui)，用于(yu)高(gao)精或高(gao)速直線(xian)(xian)往復運動(dong)場合，且可(ke)以承(cheng)擔一定(ding)的扭矩(ju)，可(ke)在高(gao)負(fu)載的情(qing)況下實現高(gao)精度的直線(xian)(xian)運動(dong)。

直(zhi)線(xian)(xian)導(dao)(dao)(dao)(dao)軌運動(dong)的(de)(de)作(zuo)用(yong)(yong)是用(yong)(yong)來(lai)支撐(cheng)和引導(dao)(dao)(dao)(dao)運動(dong)部件(jian)，按給定(ding)的(de)(de)方向做往(wang)復直(zhi)線(xian)(xian)運動(dong)。　直(zhi)線(xian)(xian)軸承主要用(yong)(yong)在(zai)自動(dong)化機(ji)械上比較多,像直(zhi)線(xian)(xian)導(dao)(dao)(dao)(dao)軌主要是用(yong)(yong)在(zai)精(jing)度(du)要求比較高(gao)的(de)(de)機(ji)械結構上,直(zhi)線(xian)(xian)導(dao)(dao)(dao)(dao)軌的(de)(de)移(yi)動(dong)元件(jian)和固定(ding)元件(jian)之間(jian)不用(yong)(yong)中(zhong)間(jian)介質，而(er)用(yong)(yong)滾動(dong)鋼球(qiu)。可(ke)以理(li)解為是一(yi)種(zhong)滾動(dong)導(dao)(dao)(dao)(dao)引，是由鋼珠在(zai)滑塊跟導(dao)(dao)(dao)(dao)軌之間(jian)無限(xian)滾動(dong)循環， 從(cong)而(er)使負載平(ping)臺沿著導(dao)(dao)(dao)(dao)軌輕易的(de)(de)高(gao)精(jing)度(du)線(xian)(xian)性運動(dong)，并將摩擦系數降至(zhi)平(ping)常傳統(tong)滑動(dong)導(dao)(dao)(dao)(dao)引的(de)(de)五十分之一(yi)，能輕易地(di)達到很高(gao)的(de)(de)定(ding)位(wei)精(jing)度(du)。滑塊跟導(dao)(dao)(dao)(dao)軌間(jian)末制單元設(she)計(ji)，使線(xian)(xian)形導(dao)(dao)(dao)(dao)軌同時承受上下左(zuo)右等(deng)各方向的(de)(de)負荷，回流系統(tong)及(ji)精(jing)簡化的(de)(de)結構設(she)計(ji)讓(rang)線(xian)(xian)性導(dao)(dao)(dao)(dao)軌有更平(ping)順(shun)且低噪(zao)音的(de)(de)運動(dong)。

滑塊-使運(yun)動由曲(qu)線轉變為(wei)直線。

直線導軌(gui)主要是(shi)用在精度(du)(du)要求(qiu)比較高(gao)的機(ji)械(xie)結(jie)構(gou)上,直線導軌(gui)的移(yi)動(dong)(dong)元件(jian)和固(gu)定元件(jian)之(zhi)間不用中間介質(zhi)，而用滾動(dong)(dong)鋼(gang)球。因(yin)為滾動(dong)(dong)鋼(gang)球適應于高(gao)速運(yun)(yun)動(dong)(dong)、摩(mo)擦系數小(xiao)、靈敏度(du)(du)高(gao)，滿(man)足(zu)運(yun)(yun)動(dong)(dong)部件(jian)的工(gong)作要求(qiu)，被廣泛應用在自動(dong)(dong)化(hua)(hua)機(ji)械(xie)上比較多,像磨床(chuang)、銑床(chuang)、車(che)床(chuang)、檢測儀器(qi)設備、木工(gong)機(ji)械(xie)、搬運(yun)(yun)機(ji)械(xie)、傳送(song)裝置、自動(dong)(dong)化(hua)(hua)機(ji)械(xie)、半導體(ti)機(ji)械(xie)、包裝機(ji)械(xie)、機(ji)械(xie)手臂、自動(dong)(dong)化(hua)(hua)機(ji)床(chuang)、激(ji)光(guang)行(xing)(xing)業、汽車(che)制造、新能(neng)源等行(xing)(xing)業。