直(zhi)線(xian)(xian)導軌又稱線(xian)(xian)軌、滑(hua)軌、線(xian)(xian)性導軌、線(xian)(xian)性滑(hua)軌，用于高(gao)精(jing)(jing)或高(gao)速直(zhi)線(xian)(xian)往復運動場合，且可(ke)(ke)以承(cheng)擔一定(ding)的(de)扭矩(ju)，可(ke)(ke)在高(gao)負(fu)載的(de)情況下實現高(gao)精(jing)(jing)度的(de)直(zhi)線(xian)(xian)運動。

直(zhi)(zhi)線(xian)(xian)(xian)(xian)導(dao)(dao)軌(gui)(gui)運(yun)動(dong)的(de)作用(yong)是(shi)(shi)用(yong)來支撐和引導(dao)(dao)運(yun)動(dong)部件，按給定(ding)的(de)方(fang)向做往復直(zhi)(zhi)線(xian)(xian)(xian)(xian)運(yun)動(dong)。　直(zhi)(zhi)線(xian)(xian)(xian)(xian)軸承主要用(yong)在(zai)自(zi)動(dong)化機械上比較多(duo),像(xiang)直(zhi)(zhi)線(xian)(xian)(xian)(xian)導(dao)(dao)軌(gui)(gui)主要是(shi)(shi)用(yong)在(zai)精度(du)要求比較高(gao)的(de)機械結構上,直(zhi)(zhi)線(xian)(xian)(xian)(xian)導(dao)(dao)軌(gui)(gui)的(de)移動(dong)元件和固定(ding)元件之間不用(yong)中間介質，而用(yong)滾動(dong)鋼球。可以理(li)解為是(shi)(shi)一(yi)種滾動(dong)導(dao)(dao)引，是(shi)(shi)由鋼珠在(zai)滑(hua)(hua)塊跟導(dao)(dao)軌(gui)(gui)之間無限滾動(dong)循環， 從而使負載平臺沿著導(dao)(dao)軌(gui)(gui)輕(qing)易(yi)的(de)高(gao)精度(du)線(xian)(xian)(xian)(xian)性運(yun)動(dong)，并(bing)將摩擦系(xi)數降(jiang)至平常傳統滑(hua)(hua)動(dong)導(dao)(dao)引的(de)五十分之一(yi)，能輕(qing)易(yi)地達到很(hen)高(gao)的(de)定(ding)位精度(du)。滑(hua)(hua)塊跟導(dao)(dao)軌(gui)(gui)間末制單(dan)元設(she)(she)計(ji)，使線(xian)(xian)(xian)(xian)形導(dao)(dao)軌(gui)(gui)同時承受上下左(zuo)右等各方(fang)向的(de)負荷，回流(liu)系(xi)統及(ji)精簡化的(de)結構設(she)(she)計(ji)讓線(xian)(xian)(xian)(xian)性導(dao)(dao)軌(gui)(gui)有(you)更平順且低噪音(yin)的(de)運(yun)動(dong)。

滑塊-使運(yun)動由曲線轉變為直線。

直線導(dao)軌(gui)主要是(shi)用(yong)在精度(du)要求(qiu)(qiu)比較高的機械結構上(shang)(shang),直線導(dao)軌(gui)的移(yi)動(dong)(dong)(dong)元件和固(gu)定元件之間不用(yong)中間介質，而用(yong)滾(gun)動(dong)(dong)(dong)鋼(gang)(gang)球(qiu)。因(yin)為滾(gun)動(dong)(dong)(dong)鋼(gang)(gang)球(qiu)適(shi)應(ying)于(yu)高速運(yun)(yun)動(dong)(dong)(dong)、摩擦系(xi)數小(xiao)、靈敏度(du)高，滿足(zu)運(yun)(yun)動(dong)(dong)(dong)部(bu)件的工作要求(qiu)(qiu)，被廣泛應(ying)用(yong)在自動(dong)(dong)(dong)化機械上(shang)(shang)比較多(duo),像磨床(chuang)、銑床(chuang)、車(che)床(chuang)、檢(jian)測(ce)儀器設(she)備(bei)、木工機械、搬運(yun)(yun)機械、傳(chuan)送裝(zhuang)置、自動(dong)(dong)(dong)化機械、半導(dao)體機械、包(bao)裝(zhuang)機械、機械手(shou)臂、自動(dong)(dong)(dong)化機床(chuang)、激(ji)光行(xing)業、汽(qi)車(che)制造(zao)、新能源等行(xing)業。