Abstract: A hydrodynamic bearing device which realizes power saving, reduction of a time period necessary for stabilizing rotation, and enhancement in durability to startup and halting of the motor at the same time by accelerating circulation of a lubricant in the vicinity of a flange with torque loss being kept low is provided. A flange (3) is fixed to one end of a shaft (2). On an inner surface of one of openings of a sleeve (1), a step portion (1C) is provided. When the shaft (2) is inserted into the sleeve (1), the flange (3) is in close vicinity to the step portion (1C). An inner diameter of the step portion (1C) is smaller in end portions in an axial direction than in a central portion. Thus, a gap between an outer surface (3C) of the flange (3) and a surface of the step portion (1C) which opposes the outer surface (3C) is narrow in the vicinity of boundaries of the outer surface (3C) of the flange (3) than in the vicinity the central portion.

Abstract: A magnet (13) for trapping abraded powder is disposed in a connecting passage between an opening of a sleeve and an opening of a hydrodynamic bearing motor, and a shaft (3), a sleeve (4), a thrust flange (7), and a thrust main plate (5) are made of an austenitic stainless. With this configuration, since the austenitic stainless acting as a nonmagnetic substance is used, it is possible to increase a degree of cleaning. Further, abraded powder of the austenitic stainless is transformed into a magnetic substance, and thus a flow of the abraded powder to the outside can be prevented by providing the magnet for trapping abraded powder in the connecting passage between an opening of a bearing and the outside of the motor.

Abstract: A spindle motor comprises a fixed shaft member, a sleeve, and an annular chucking portion. The fixed shaft member has an annular collar protruding outward from and substantially perpendicular to the outer peripheral surface of said fixed shaft member, and also has a thrust flange provided a specific distance away from said annular collar. The sleeve component is monolithic with a hub component The annular chucking portion is formed to include a surface along an axial direction outside said thrust flange in a diameter direction of said thrust flange. The annular chucking portion is disposed at a position in an axial direction that includes a vertical position of a surface to which said disk is attached.

Abstract: A hydrodynamic bearing for a hard disk drive device is disclosed. An oil is filled in a clearance between an inner surface of the hub and an outer surface of the shaft, whereby a hydrodynamic radial bearing is formed between the inner periphery of the hub and the outer periphery of the shaft, and a hydrodynamic thrust bearing is formed between the top face of the shaft and the thrust plate. Between an outer peripheral part at the base end of the shaft and an inner peripheral part at the open end of the hub is formed a seal part in which a larger clearance is formed between the shaft and the hub than a clearance in the hydrodynamic radial bearing and in which the oil surface is positioned. An oil surface adjusting hole and a plug for sealing the hole are provided in the case opposite the seal part.

Abstract: A dynamic pressure gas bearing motor in which a radial dynamic pressure gas bearing and a thrust dynamic pressure gas bearing are ensured to have sufficient length and diameter even though the clamping screw holes for introducing screws to reliably hold a disk are formed in the top wall of the motor rotation body.

Abstract: Object: A spindle motor of the type in which both ends of a shaft are fixed has a structure in which both ends of a hydrodynamic bearing are open to the atmosphere, and when the rotational precision of rotating bodies is poor, the bearing is subjected to a great deal of fluctuating stress, and leakage of the lubricant occurs. Means for Solution: In a spindle motor having a fluid bearing in which a narrow gap is formed between the surface of a fixed shaft member and a sleeve component (rotating member), and this gap is filled with a lubricating fluid, the shaft member has an annular collar formed so as to protrude substantially perpendicularly to the cylindrical surface of the shaft member. The rotating member is such that the sleeve component fitted over the shaft member is constituted integrally with a hub component that fixes a magnetic disk, and an annular seal member is fixed to the upper end side of the shaft member.

Abstract: A dynamic pressure gas bearing motor in which a radial dynamic pressure gas bearing and a thrust dynamic pressure gas bearing are ensured to have sufficient length and diameter even though the clamping screw holes for introducing screws to reliably hold a disk are formed in the top wall of the motor rotation body.

Abstract: A magnet (13) for trapping abraded powder is disposed in a connecting passage between an opening of a sleeve and an opening of a hydrodynamic bearing motor, and a shaft (3), a sleeve (4), a thrust flange (7), and a thrust main plate (5) are made of an austenitic stainless. With this configuration, since the austenitic stainless acting as a nonmagnetic substance is used, it is possible to increase a degree of cleaning. Further, abraded powder of the austenitic stainless is transformed into a magnetic substance, and thus a flow of the abraded powder to the outside can be prevented by providing the magnet for trapping abraded powder in the connecting passage between an opening of a bearing and the outside of the motor.

Abstract: A hydrodynamic bearing device which realizes power saving, reduction of a time period necessary for stabilizing rotation, and enhancement in durability to startup and halting of the motor at the same time by accelerating circulation of a lubricant in the vicinity of a flange with loss torque being kept low is provided. A flange (3) is fixed to one end of a shaft (2). On an inner surface of one of openings of a sleeve (1), a step portion (1C) is provided. When the shaft (2) is inserted into the sleeve (1), the flange (3) is in close vicinity to the step portion (1C). An inner diameter of the step portion (1C) is smaller in end portions in an axial direction than in a central portion. Thus, a gap between an outer surface (3C) of the flange (3) and a surface of the step portion (1C) which opposes the outer surface (3C) is narrow in the vicinity of boundaries of the outer surface (3C) of the flange (3) than in the vicinity the central portion.

Abstract: A hard disk drive device is provided, which is designed small, thin, and at low-cost. The hard disk drive device includes a case with an upright shaft, and a cylindrical hub coupled to the shaft. One end of the hub is closed by a thrust plate so that the hub has a bottomed cylindrical shape, and a hard disk is fixedly mounted on an outer peripheral part of the hub. An oil is filled in a clearance between an inner surface of the hub and an outer surface of the shaft, whereby a hydrodynamic radial bearing is formed between the inner periphery of the hub and the outer periphery of the shaft, and a hydrodynamic thrust bearing is formed between the top face of the shaft and the thrust plate. Between an outer peripheral part at the base end of the shaft and an inner peripheral part at the open end of the hub is formed a seal part in which a larger clearance is formed between the shaft and the hub than a clearance in the hydrodynamic radial bearing and in which the oil surface is positioned.

Abstract: A gas dynamic bearing motor is provided that is capable of setting a bearing radius to a large value to obtain a sufficient radial stiffness, and preventing lock of the bearing and scattering of wear powder outside the bearing. An annular groove 11 is provided on a lower end surface 87 of a hub 3 to thereby enable a deformation of an inner circumferential surface 82 of the hub 3 when recording disks 9 are loaded on the hub 3 to be suppressed to a small value, thereby enabling partial contact in the radial bearing to be suppressed and lock of the bearing to be prevented. Further, a protrusion 12 is provided on a base 7 in a circumferential direction and fitted in the annular groove 11 to construct a labyrinth seal, thereby enabling scattering of wear powder generated on bearing surfaces outside the bearing to be prevented.

Abstract: A gasdynamic bearing motor is provided that is capable of setting a bearing radius to a large value to obtain a sufficient radial stiffness, and preventing lock of the bearing and scattering of wear powder outside the bearing. An annular groove 11 is provided on a lower end surface 87 of a hub 3 to thereby enable a deformation of an inner circumferential surface 82 of the hub 3 when recording disks 9 are loaded on the hub 3 to be suppressed to a small value, thereby enabling partial contact in the radial bearing to be suppressed and lock of the bearing to be prevented. Further, a protrusion 12 is provided on a base 7 in a circumferential direction and fitted in the annular groove 11 to construct a labyrinth seal, thereby enabling scattering of wear powder generated on bearing surfaces outside the bearing to be prevented.