Fluid dynamic bearing device and motor with same

A fluid dynamic bearing device, comprising:

• a housing having a bottomed cylindrical shape with an end portion on one end side in an axial direction being opened and an end portion on another end side in the axial direction being closed,
• a bearing member, which is arranged along an inner periphery of the housing, and has a chamfered portion at an inner peripheral edge portion on one end side in the axial direction, the bearing member being porous;
• and
• a radial bearing portion, which is configured to support the shaft member in a radial direction with an oil film of lubricating oil formed in a radial bearing gap defined between an inner peripheral surface of the bearing member and an outer peripheral surface of the shaft member to be inserted along an inner periphery of the bearing member,
• wherein the shaft member is supported in a thrust direction by an inner bottom surface of the housing,
• wherein a charging amount of the lubricating oil into an internal space of the housing is adjusted so that, within a range of a use temperature, an oil level of the lubricating oil is positioned on another end side in the axial direction with respect to the end portion of the chamfered portion on one end side in the axial direction,
• wherein the bearing member integrally comprises:
• a small-diameter cylindrical portion, which is arranged on one end side in the axial direction, and has a relatively smaller outer diameter dimension;
• and
• a large-diameter cylindrical portion, which is arranged on another end side in the axial direction, and has a relatively larger outer diameter dimension, and
• wherein, under a state in which an end surface of the small-diameter cylindrical portion on one end side in the axial direction is exposed to an atmosphere, the large-diameter cylindrical portion of the bearing member is sandwiched from both sides in the axial direction between an annular member, which is arranged between the small-diameter cylindrical portion and a tubular portion of the housing, and a bottom portion of the housing so that the bearing member is fixed along an inner periphery of the housing.