Using a combination of air pressure and vacuum, New Way VPL air bearings hold themselves down while simultaneously lifting themselves from a guide surface. By adjusting the vacuum and the pressure separately, the fly height and stiffness of these vacuum preloaded air bearings can be optimized.
This arrangement is ideal for applications where preloading is difficult or impossible. Obviously, there is a cost advantage because only one flat guide surface is necessary. (Opposed bearing preloading requires two flat guide surfaces that are parallel.
There is also a significant technical advantage. Both "x" and "y" axes can be supported by a single bearing plane. Further, the adjustability of film thickness can be used for focusing, squaring and sub-microinch vertical positioning over a range of several thousandths of an inch.
These bearings are perfect for ultra-precision applications because of their adjustable fly heights, fast settling time and naturally stable design. Using VPLs eliminates the need for stacked linear axes, and the pitch and roll errors inherent therein. They also reduce stack height, as well as Abbe errors.
The combination of air pressure and vacuum necessitates a different mounting methodology from New Way flat air bearings. The typical socket would not provide for bi-directional stiffness because the ball would pull out. New Way has engineered a flexure mount to provide equal stiffness in both directions, while providing a low pivot point. Because there is no stick-slip type friction in the flexture mount, even the smallest amount of angular adjustment is possible.
Contact the New Way Sales Department for more information or Technical Support.