Linear Ball Bearings
There is always a model within a large industrial category that is able to do what no other model can do. Within the spectrum of linear bearings, the linear rotary bearing is that model. However, just because it can move in ways other linear bearings cannot does not mean it is the most popular. In fact, most industries and individual companies that purchase linear bearings want one-way movement along a single axis with as little friction built-up during the process as possible. This can be achieved with a linear roller bearing or a slide bearing, no special movement requirements necessary.
However, for those special circumstances that demand movement on a more complex plane, the linear rotary is perfect. Able to move an object or system along a one-way plane, they are also able to move certain parts anywhere within 360º. The basic mechanics of a linear rotary involve races or tracks that serve as a framework for the moving parts. Ball bearings are installed within these, to which shafts are attached that are usually millimeters in length. The shafts may move in and out of the linear rotary freely while the ball bearings spin to create low-friction movement for the system.
High precision is almost always required of a linear bearing, including the linear rotary bearings. This is why they are always made of the highest quality materials, such as ceramic, stainless steel, aluminum or certain plastic alloys. The materials are also expected to be well crafted to the perfect size or they will rub together too closely and produce friction that will be damaging to the material as well as the machine or system they are allowing movement. Such a system can be found in a plethora of environments, such as medical facilities, dentist offices, manufacturing factories, agricultural and construction settings, electronics and the automotive industry.