Hard drive bearings

Hard drive bearings

There are two basic types of hard drive bearings, one based on standard contact ball bearings and the other based on liquid bearings.

The shape, radius, and surface roughness of the raceway are crucial for the operational performance and noise characteristics of such bearings. Taylor Hobson has many Form Talysurf inductance series instruments suitable for measuring the shape and surface roughness characteristics of hard drive bearings.

Liquid bearing

In liquid bearings, the bearing function is replaced by a lubricant layer that is less than one tenth the thickness of a human hair. The rotor supported by bearings essentially rotates around the axis. By eliminating the contact between metals in liquid bearings, non repetitive jumping caused by surface defects can be eliminated. This can reduce the track spacing and increase the number of tracks per inch of disk.

The control of surface roughness, roundness, and waviness is crucial for the performance of liquid bearings. But usually, machined grooves in the shaft and rotor of FDB can also help form a stable lubricant layer.

Through collaboration with manufacturers, Taylor Hobson has developed a specialized analysis tool for analyzing the shape and ratio of grooves on FDBs.