Patent ID: 8449189

Claim:
A motor provided with an aerodynamic pressure bearing mechanism, the mechanism comprising: a rotating axis; a fixed member having a surface facing the surface of the rotating axis with a predetermined bearing clearance; and herring bone grooves composed of N number of grooves placed on the surface of the rotating axis at regular intervals in the rotational direction and configured to generate dynamic pressure within said bearing clearance during rotation, wherein the N number of grooves composing said herring bone grooves are disposed at a predetermined intake angle β greater than 0 and less than or equal to 90 degrees towards the center in the axial direction of the rotating axis with an edge of one end part in the axial direction of said rotating axis as one end of the grooves, and at a ratio between the length of said grooves in the axial direction and the axial diameter of the rotating axis being greater than 0.2 and less than 0.8, and wherein, when rotating at a rotation frequency of M greater than 40 krpm and less than or equal to 60 krpm in an environment in which the ambient humidity is approximately 60% RH, and wherein said herring bone grooves are composed of N number of grooves at positions where maximal pressure values of dynamic pressure variation in said bearing clearance caused during rotation of said rotating axis appears, and at intervals such that N number of minimal pressure values appearing in alternation with said maximal pressure values, said minimal pressure values become equal to or lower than 1.7 atm as a condensation pressure value.