HYDRODYNAMIC BEARING DEVICE AND SPINDLE MOTOR HAVING THE SAME AND DRIVING DEVICE OF RECORDING DISK

摘要

Disclosed is a hydrodynamic bearing device comprising: a fixed part; and a rotation part forming a bearing gap where a lubrication fluid is charged and a sealing part connected to the bearing gap to allow a vapor-liquid interface to be arranged thereon. The fixed part and the rotation part are connected to the sealing part to receive the lubrication liquid when the lubrication liquid charged into the bearing gap is leaked. A surface area of the vapor-liquid interface moved due to a leakage of the lubrication liquid is increased, thereby increasing the force applied to the vapor-liquid interface due to a capillary phenomenon. The bearing gap has a flow restriction gap having an interval narrower than another part of the bearing gap to restrict the flow of the lubrication liquid. According to the present invention, scattering of the lubrication liquid can be prevented.