金屬直線軸承是一種以低成本生產的直線運動系統，用于無限行程與圓柱軸配合使用。廣泛應用于精密？機床、紡織機械、食品包裝機械、印刷機械等工業機械的滑動部件。

　　Metal linear bearings are a low-cost linear motion system designed for use with infinite travel and cylindrical shafts. Widely used in precision? Sliding parts of industrial machinery such as machine tools, textile machinery, food packaging machinery, printing machinery, etc.

　　金屬直線軸承是一種以低成本生產的直線運動系統，用于無限行程與圓柱軸配合使用。廣泛應用于精密機床、紡織機械、食品包裝機械、印刷機械等工業機械的滑動部件。直線導軌通常按照形式如下安裝：

　　Metal linear bearings are a low-cost linear motion system designed for use with infinite travel and cylindrical shafts. Widely used as sliding components in industrial machinery such as precision machine tools, textile machinery, food packaging machinery, printing machinery, etc. Linear guides are usually installed in the following form:

　　1.一端固定——另一端支承?導軌一端固定，另一端支承。固定端同時承受軸向力和徑向力；支承端只承受徑向力，而且能作微量的軸向浮動，可以減少或避免因導軌自重而出現的彎曲，同時導軌熱變形可以自由向一端伸長。這種結構使用廣泛，目前國內中小型數控車床、立式加工中心等均采用這種結構。

　　1. One end fixed - the other end supports the rail with one end fixed and the other end supported. The fixed end simultaneously bears axial and radial forces; The supporting end only bears radial force and can undergo slight axial floating, which can reduce or avoid bending caused by the self weight of the guide rail. At the same time, the thermal deformation of the guide rail can be freely extended towards one end. This structure is the most widely used, currently used in small and medium-sized CNC lathes, vertical machining centers, and other applications in China.

　　2.一端固定——一端自由? ?導軌一端固定，另一端自由。固定端軸承同時承受軸向力和徑向力，這種支承方式用于行程小的短導軌或者用于全閉環的機床，因為這種結構的機械定位精度是不可靠的，特別是對于長徑比大的導軌（直線導軌相對細長），熱變性是很明顯的，1.5m長的導軌在冷、熱的不同環境下變化0.05~0.10mm是很正常的。但是由于他的結構簡單，安裝調試方便，許多高精度機床仍然采用這種結構，但是必須加裝光柵，采用全閉環反饋。

　　2. Fixed at one end - One end is free and the guide rail is fixed at one end, while the other end is free. Fixed end bearings simultaneously bear axial and radial forces. This support method is used for short guide rails with small stroke or for fully closed-loop machine tools, because the mechanical positioning accuracy of this structure is the least reliable, especially for guide rails with a large aspect ratio (linear guide rails are relatively slender), and thermal deformation is very obvious. It is normal for a 1.5m long guide rail to change by 0.05-0.10mm in different cold and hot environments. However, due to its simple structure and easy installation and debugging, many high-precision machine tools still use this structure, but it is necessary to install gratings and adopt fully closed-loop feedback.

　　3.兩端固定? ?導軌兩端均固定。固定端軸承都可以同時承受軸向力，這種支承方式，可以對導軌施加適當的預緊力，提高導軌支承剛度，可以部分補償導軌的熱變形。? ?對于大型機床、重型機床以及高精度鏜銑床常采用此種方案。但是，這種導軌的調整比較繁瑣，如果兩端的預緊力過大，將會導致導軌終的行程比設計行程要長，螺距也要比設計螺距大。如果兩端鎖母的預緊力不夠，會導致相反的結果，并容易引起機床震動，精度降低。所以，這類導軌在拆裝時一定要按照原廠商說明書調整，或借助儀器（雙頻激光測量儀）調整。

　　3. Both ends of the fixed guide rail are fixed. Fixed end bearings can simultaneously withstand axial forces. This support method can apply appropriate pre tension to the guide rail, improve the stiffness of the guide rail support, and partially compensate for the thermal deformation of the guide rail. This scheme is commonly used for large machine tools, heavy-duty machine tools, and high-precision boring and milling machines. However, the adjustment of this type of guide rail is relatively complicated. If the pre tension force at both ends is too large, it will result in the final stroke of the guide rail being longer than the design stroke and the pitch being larger than the design pitch. If the pre tightening force of the locking nut at both ends is insufficient, it will lead to opposite results and easily cause machine tool vibration, resulting in reduced accuracy. So, when disassembling and assembling such guide rails, it is necessary to adjust them according to the original manufacturer's instructions or with the help of an instrument (dual frequency laser measuring instrument).