Patent ID: 6955469

Claim:
A dynamic pressure bearing device comprising: a shaft; a rotary member being fixed on one end of said shaft; a dynamic pressure bearing member having a center hole, said shaft being inserted into the hole in a freely rotatable manner relative to the dynamic pressure bearing member; a thrust dynamic pressure bearing section provided in a thrust opposing region where an end surface in an axial direction of the dynamic pressure bearing member is opposed to an end surface in the axial direction of the rotary member by a minuscule gap therebetween, wherein the thrust dynamic pressure bearing section rotatably supports the rotary member in the axial direction of the rotary member; a radial dynamic pressure bearing section provided in a minuscule gap section where an outer circumference surface of said shaft is opposed to an inner circumference surface of said hole by a minuscule gap therebetween, the minuscule gap section extending in the axial direction to reach said thrust opposing region along the outer circumference surface of said shaft; lubricating fluid filling continuously from said minuscule gap of said thrust opposing region to said minuscule gap of said minuscule gap section; a cover, closing an opening section at a bottom end of said hole to prevent said lubricating fluid inside of said radial dynamic pressure bearing section from leaking outside; a pumping device provided in an outer circumference part of the thrust opposing region to pressurize a lubricating fluid inside the thrust opposing region inwardly in a radial direction, wherein the pumping device generates an inward pressurizing force larger than a rotational centrifugal force applied to the lubricating fluid within the thrust opposing region during rotation.