Guide rails or linear bearings are suitable for both backwards and forwards movements. In the case of guide rails, we make a distinction according to whether the forces are transferred by rolling or sliding elements. The guides consist of a combination of rails and slides, of shafts with linear ball bearings or of rails with roller or ball cages in between. Driven linear units are single- or multi-shaft complete systems consisting of a mechanical guide system, a drive motor and the associated control.
Linear guides are systems that can be installed immediately, mostly for unlimited stroke lengths. Cage guides are usually used for limited stroke lengths due to the kinematics of the cage. This type of bearing absorbs forces from all directions, except from the direction of movement, and absorbs all shaft torques. Shaft guides with linear ball bearings are suitable for loads from two directions and compensate for static misalignments of the shaft. Most units are already prestressed ex works to achieve high rigidity and accuracy. They can also be prestressed during installation. Thanks to different accuracy and prestressing classes, applications with high requirements for accuracy and positioning can also be implemented without any difficulty.
The requirements for linear components are very varied. This is also true of the range of applications. Speed and accuracy in particular are required for transport and supply systems, whereas precision and rigidity are more important for measuring machines, for example. Each linear construction has characteristic properties, making it particularly suitable for certain applications. General rules for choosing the guide type can only be drawn up under certain conditions. Almost always, several factors must be taken into account and weighed up against each other. For example, in addition to load, acceleration, speed and stroke length, account must also be taken of the impact of factors including temperature, lubrication, vibration and maintenance.