Unimatic Engineers is introducing a novel design of crossed-roller linear bearing that eliminates the problem of cage creep - a recognised and yet difficult-to-manage issue that ultimately shortens the lifetime of the linear bearing and can lead to premature failures. The solution offered by Unimatic is the ACC (Anti Cage Creep) system that promises zero cage creep, even in extreme dynamic applications. The ACC system is available with all RSDE-series linear bearing railsets, in all accuracy grades.
Cage creep can occur in non-recirculating linear bearing applications where vibrations, improper mounting, inadequate tolerancing on the mounting surfaces, uneven preloading or moment loading are present. The problem is particularly acute in applications characterised by extreme acceleration and deceleration rates. In such applications, over a period of time the cage creeps out from the original position, resulting in an increase in friction, a reduction in the travel length and premature wear of the linear bearings. Not only does this impact on the efficient working of the machine, it also shortens the lifetime of the bearing and can lead to premature failure.
The ACC design overcomes these problems, ensuring zero cage creep in all demanding applications, including extreme dynamic applications with accelerations and/or decelerations up to 150m/s2. The system is also suitable for use in challenging environmental conditions. The system completely eliminates the problem of cage creep with no increase in friction, no reduction in accuracy and no influence on lubrication. And because the system is integrated into the design of the linear bearing without affecting the external dimensions, existing linear bearings can be readily replaced with ACC alternatives.
The ACC bearings offered by Unimatic feature an all-metal design that provides dependable service in the most demanding applications where other designs - particularly those that contain plastics - may fail. The system is well suited to meeting the high-speed, high-precision demands of the electronics and semiconductor industries, and are cost-effective in general machinery applications for OEMs looking to increase parameters such as speed and travel to the limits without compromising long-term accuracy.
Linear bearings with the ACC solution can operate over temperature ranges from -40 to +80degC, which is a significant advantage over similar-looking systems using plastic components.