Design of hydrodynamic bearing for mobile hard disk drives

This paper discusses a technical issue related to the making of hydrodynamic bearings being more reliable and more resistant to temperature and pressure changes. We have designed and evaluated a prototype of hydrodynamic bearing that is free from oil film disruption and resistant to environmental changes. This is achieved by adding an oil circulation function (asymmetric herringbone grooves and a circular port) and an air/liquid separation function (an oil reservoir with a slanted narrow gap) in the bearing design, thus enabling it to forcibly expel any air inside the bearing and enhancing the performance of hydrodynamic bearing spindle motors.