Abstract: There is provided a spindle motor including: a shaft connected directly or indirectly to a base member and having a depression groove formed in a central portion of an outer peripheral surface thereof; a sleeve rotatably installed on the shaft and having a communication hole formed so as to be connected to the depression groove; and a rotor hub fixedly installed on the sleeve to thereby rotate together therewith, wherein the communication hole is inclined so that lubricating fluid may be easily injected into the depression groove, and the sleeve has a fluid storage part formed on an outer peripheral surface thereof, the fluid storage part being connected to the communication hole and temporarily storing the lubricating fluid therein.

Abstract: A disk drive unit includes a rotor configured to rotate a disk accommodated within a disk accommodating space and set thereon, a fixed body configured to rotatably support the rotor, a fluid dynamic pressure generating part provided between the fixed body and the rotor, and a plurality of ring-shaped members, provided in an overlapping manner along a direction of a rotational axis of the rotor within a space that communicates the disk accommodating space and a gas-liquid interface of the lubricant, and covering a gap between the rotor and the fixed body.

Abstract: There is provided a spindle motor including: a base part including a base member and a lower thrust member fixedly installed on the base member; a shaft having a lower end portion fixedly installed on the base part; an upper thrust member fixedly installed on an upper end portion of the shaft; a sleeve disposed between the upper and lower thrust members and rotatably installed on the shaft; and a rotor hub fixedly installed on the sleeve to thereby rotate together therewith, wherein the sleeve includes a connection hole formed therein in order to connect an inner diameter portion thereof to an outer peripheral surface thereof.

Abstract: A rotating device comprises a hub, a shaft, and a bearing unit. The bearing unit includes a surrounding portion arranged to surround the shaft, and a facing portion arranged to face an end of the shaft. A gap between the shaft and the surrounding portion includes two dynamic pressure generation portions and an intermediate portion arranged between the two dynamic pressure generation portions. The bearing unit further includes a path of a lubricant arranged to connect one side of one dynamic pressure generation portion and the intermediate portion. The shaft and the bearing unit are arranged so that the lubricant pushed out of the other dynamic pressure generation portion towards a gap between the end of the shaft and the facing portion stays in the gap.

Abstract: A first seal portion having a surface of a lubricating oil defined therein is defined between a sleeve portion and a bearing housing. A side communicating channel arranged to bring a first seal gap and a thrust gap into communication with each other is defined either between a sleeve portion and a bearing housing or in an outer circumferential portion of a sleeve portion. A second seal portion having another surface of a lubricating oil defined therein is defined in a gap constituted by a side minute gap between a thrust plate and a bearing housing and a lower minute gap between a thrust plate and a cap member.

Abstract: A dynamic pressure bearing apparatus includes a bearing portion; a shaft; a substantially annular bushing; a radial dynamic pressure bearing portion; and a seal gap. A minute horizontal gap extending radially is defined between an upper surface of the bearing portion and a lower surface of the bushing. The seal gap is arranged to be in communication with an exterior space through the horizontal gap.

Abstract: A thrust shaft for a fan has a shaft body with an enlarged disk adjacent one axial end to provide a rotating surface in a pair of thrust bearings. A first cylindrical portion extends from the disk in a first direction, and a second cylindrical portion extending from the disk in a second opposed direction. The second cylindrical portion has a hollow bore, and there are a plurality of holes extending through the second cylindrical portion to communicate an outer periphery with the bore. A ratio of the diameter of the bore to a diameter of the plurality of air holes is between 6.60 and 7.00. A ratio of an overall length of the second cylindrical portion, and a distance from a face of the enlarged disk to a center of the holes is between 14.4 and 15.2. A thrust bearing assembly, a fan, a cabin air supply system, and a method are also disclosed.

Abstract: It is an object of the present invention to provide a bearing member having a highly accurate dynamic pressure generating portion stably at low cost. Dynamic pressure grooves (8a1) and (8a2) are formed as the dynamic pressure generating portions on an inner circumferential surface of the electroforming portion (10) by an electroforming process, and injection molding is performed by using a resin while inserting the electroforming portion (10), thereby forming a bearing member (8). A shaft member (2) is inserted into an inner circumference of the bearing member.

Abstract: In a bearing mechanism according to a preferred embodiment of the present invention, a seal portion in which a surface of a lubricating oil is located is defined in a seal gap defined between an outer circumferential surface of a first tubular portion and an inner circumferential surface of a second tubular portion. The first tubular portion includes, in an area where the outer circumferential surface of the first tubular portion is in contact with the lubricating oil, a maximum outside diameter portion at which the outside diameter of the first tubular portion is greatest, an annular shoulder portion including a surface facing toward the surface of the lubricating oil and at which the outside diameter is smaller than at the maximum outside diameter portion, and an inclined portion at which the outside diameter gradually decreases from the annular shoulder portion toward the surface of the lubricating oil.

Abstract: Provided herein is an apparatus, including a fluid dynamic bearing, wherein the fluid dynamic bearing includes a set of pressure-generating grooves, and wherein the set of pressure-generating grooves includes a plurality of chevron-shaped grooves, each chevron-shaped groove including at least two selected from a non-uniform depth, non-uniform angle, a non-uniform width, or a non-uniform length, selected to provide a predetermined spindle-motor stiffness to the journal bearing during steady-state operation and during a shock event.

Abstract: An inner peripheral surface and a lower end surface of a bearing sleeve made of a sintered metal are each formed into a smooth cylindrical surface or a flat surface that does not have a dynamic pressure generating portion. Thus, a step of forming the dynamic pressure generating portion can be omitted from a manufacturing step of the bearing sleeve, and cost of dies can be markedly reduced. Further, the inner peripheral surface of the bearing sleeve is formed into the smooth cylindrical surface, and hence a radial dynamic pressure generating portion is formed on an outer peripheral surface of a shaft member. However, the outer peripheral surface of the shaft portion is accessible to tools, and hence the radial dynamic pressure generating portion can be formed easily with high accuracy. As a result, accuracy of a radial bearing gap is enhanced so that a bearing rigidity is enhanced.

Abstract: A fluid dynamic bearing system having pressure-generating surface patterns that comprises at least two bearing parts that are rotatable with respect to one another and form a bearing gap filled with bearing fluid between associated bearing surfaces. The surface patterns are disposed on at least one bearing surface that is defined by a first rim and a second rim, hydrodynamic pressure being built up within the bearing gap on rotation of the bearing parts with respect to one another. At least parts of the surface patterns extend from the first rim to the second rim of the bearing surface.

Abstract: There are provided a spindle motor including a second thrust member installed on a base member; a shaft installed on the second thrust member; a sleeve disposed above the second thrust member and installed to be rotatable with respect to the shaft; a rotor hub coupled to the sleeve; and a first thrust member disposed above the sleeve and installed on the shaft, wherein the sleeve includes a circulation hole penetrating therethrough in an axial direction, the sleeve and the first thrust member include a first thrust bearing formed therebetween and the sleeve and the second thrust member include a second thrust bearing formed therebetween, and an area by which an upper end portion of the circulation hole is overlapped with the first thrust bearing is larger than an area by which a lower end portion of the circulation hole is overlapped with the second thrust bearing.

Abstract: A rotary electric machine for a wind power turbine for generating electric power has a tubular stator having a plurality of stator segments; a tubular rotor which has a plurality of rotor segments, is located inside the tubular stator, and rotates about an axis of rotation with respect to the tubular stator; a sleeve located at least partly inside the tubular rotor and connectable to a supporting frame of the wind power turbine; and a bearing located inside and fixed to the sleeve, and which supports the tubular rotor rotating with respect to the sleeve.

Abstract: A bearing assembly is disclosed that includes a sleeve having an opening formed therein and a shaft positioned within the opening of the sleeve such that a gap is formed between an inner surface of the sleeve and an outer surface of the shaft. A lubricant is disposed in the gap and a plurality of grooves are formed on at least one of the outer surface of the shaft and the inner surface of the sleeve. An anti-wetting coating is disposed on the at least one of the outer surface of the shaft and the inner surface of the sleeve between adjacent grooves of the plurality of grooves.

Abstract: A charging device may include a shaft rotatably mounted on at least one slide bearing in a shaft bearing region. At least one flow opening for introducing and discharging a fluid may be defined on the shaft bearing region, wherein the shaft in the shaft bearing region may have two outer portions each running in a circumferential direction and axially binding an inner portion. At least one of the outer portions on its surface may include at least one microstructure.

Abstract: There is provided a spindle motor including: upper and lower thrust parts fixedly installed on a shaft; a reception part formed in the rotor hub to thereby receive an end portion of the upper thrust part and form an oil interface together with the upper thrust part; and a clamp fixing part inserted into the reception part while having a clearance with the upper thrust part, and guiding a position of a clamp for fixing the recording medium.

Abstract: A bearing system for a rotor in rotating machines, such as compressors, pumps, turbines, expanders, has points of bearing and sealing for the rotor each being in the form of a combined bearing and sealing formed by a stator situated within a rotating machine house and surrounding the rotor. The stator is formed with a bore, whereby an annular clearance is created between stator and rotor, and the bore is having sectional area gradually increasing in the direction of larger pressure within the rotating machine.

Abstract: A hydrodynamic bearing assembly includes a shaft; a sleeve having a shaft hole formed therein so that the shaft is rotatably inserted thereinto; and first and second dynamic pressure generation grooves provided in at least one of an outer surface of the shaft and an inner surface of the sleeve and having a herringbone pattern including V-shaped portions in which upper and lower wings are provided to generate dynamic pressure in lubricating fluid filling a bearing clearance between the shaft and the sleeve at the time of rotation of the shaft. The first dynamic pressure generation groove has a V-shaped portion of which an upper wing is longer than a lower wing, and the second dynamic pressure generation groove is disposed below the first dynamic pressure generation groove in an axial direction and has a V-shaped portion of which a lower wing is longer than an upper wing.

Abstract: A fluid dynamic bearing device which can exhibit high bearing performance is provided at low costs by forming a highly accurate bearing gap. At least a region in the outer circumferential surface of a shaft which faces the radial bearing gap is constituted of an electroformed part, and the region of the shaft excluding the electroformed part is constituted of a resin portion.

Abstract: A sintered metal bearing member is provided that includes radial bearing surfaces arranged at two regions spaced apart from each other in an axial direction on an inner peripheral surface. The bearing member includes radial dynamic pressure generating portions in contact with the radial bearing surfaces. The radial dynamic pressure generating portions are formed on the radial bearing surfaces. The bearing member includes a thrust bearing surface arranged on at least one of the end surfaces and a thrust dynamic pressure generating portion for generating a dynamic pressure in the lubricating oil in contact with the thrust bearing surface. The thrust dynamic pressure generating portion is formed on the thrust bearing surface. The bearing member includes a middle relief portion arranged between the radial bearing surfaces in the axial direction. The middle relief portion has a larger diameter than the radial bearing surfaces.

Abstract: There are provided a spindle motor and a hard disk drive including the same. The spindle motor includes: a sleeve supporting a shaft so that an upper end of the shaft protrudes upwardly in an axial direction and a bearing clearance filled with a lubricating fluid formed between the sleeve and the shaft; a housing provided so as to enclose an outer peripheral surface of the sleeve and forming a circulation hole between the housing and the sleeve in the axial direction; and a rotor hub fixedly installed on an upper end portion of the shaft in the axial direction, wherein a connection part is formed between the housing and the rotor hub so as to allow a sealing part on which a liquid-vapor interface is disposed and the circulation hole to be in communication with each other.

Abstract: A fluid dynamic bearing device 1 has a bearing sleeve 8, a shaft member 2 which is inserted in the inner periphery of the bearing sleeve, a housing 7 which is formed by pressing, has the bearing sleeve 8 press-fitted in the inner periphery thereof, and has a stepped section 7d which engages with the end surface of the bearing sleeve and is located ahead in the direction of press-fitting of the bearing sleeve 8, a thrust receiver 9 which is in contact with and supports an end of the shaft member 2, and a seal portion 10 which prevents oil from leaking from the inside of the housing. A dynamic pressure generating groove 8a1 for generating fluid dynamic pressure in a radial bearing gap between the outer peripheral surface of the shaft member 2 and the inner peripheral surface of the bearing sleeve 8 is formed in the inner peripheral surface of the bearing sleeve 8.

Abstract: A rotary device includes a fixed body including a shaft; a rotary body including a sleeve being configured to surround the shaft through lubricant; and first and second taper seals provided in a space between the fixed body and the rotary body in which gas-liquid interfaces of the lubricant exist, respectively, when the rotary device is operated, the first and taper seals being configured such that a lower limit of a filling ratio of the second taper seal corresponds to a predetermined range of the filling ratio of the first taper seal including its lower limit of the filling ratio, and an upper limit of the filling ratio of the second taper seal corresponds to a predetermined filling ratio of the first taper seal that is larger than an upper limit of the predetermined range and lower than an upper limit of the first taper seal.

Abstract: Provided herein is an apparatus including a stationary portion having a thrust cup; a rotating portion having a sleeve configured to be rotatable with respect to the stationary portion; a first axially extending space defined by the thrust cup and the sleeve, wherein the first axially extending space includes a second portion positioned above a first portion of the first axially extending space; a capillary seal in the first portion of the first axially extending space; and a labyrinth seal, in the second portion of the first axially extending space.

Abstract: In order to effect a seal a porous material which comprises one side of two opposing surfaces is used to restrict and evenly distribute externally pressurized gas, liquid, steam, etc. between the two surfaces, exerting a force which is opposite the forces from pressure differences or springs trying to close the two faces together and so may create a non-contact seal that is more stable and reliable than hydrodynamic seals currently in use. A non-contact bearing is also disclosed having opposing surfaces with relative motion and one surface issuing higher than ambient pressure through a porous restriction, wherein the porous restriction is part of a monolithic porous body, or a porous layer, attached to lands containing a labyrinth, the porous restriction and lands configured to not distort more than 10% of a gap created from differential pressure between each side of the porous restriction.

Abstract: A fluid bearing device is manufactured with a high adhesive strength in fixing another member by adhesion to a resin housing. A bearing sleeve is secured in position inside the resin housing, and a shaft member is radially supported in a non-contact fashion by a dynamic pressure action of lubricant generated in a radial bearing clearance between the shaft member and the bearing sleeve. A metal bracket for mounting the stator coil of a motor is fixed by adhesion to the outer periphery of the housing, in which the adhesion portion of the outer periphery of the housing to be fixed to the bracket is roughened, setting the surface roughness to 0.5 ?mRa to 2.0 ?mRa.

Abstract: A shaft member is provided with a shaft portion and a flange portion coupled with a lower end surface of the shaft portion. The shaft portion is formed into a complete circular shape in cross section, and the flange portion is provided with a through-hole in which a part of a circumferential region is retracted to a radially outer side with respect to a lower end of the shaft portion so as to exhibit a non-circular shape. The shaft portion and the flange portion are coupled with each other in a state of butting the lower end surface of the shaft portion and an upper end surface of the flange portion against each other. With this, a fluid path is formed by opening both end surfaces of the flange portion.

Abstract: A rotating device includes a shaft body having a shaft, a first flange extending in the radial direction from the side face of the shaft, and a second flange extending outwardly of the radial direction from another end side, a freely rotatable bearing body including a shaft encircling member present between the second flange and the first flange in the axial direction, a radial dynamic pressure generating groove provided in either one of the shaft and the shaft encircling member, a first thrust dynamic pressure generating groove provided in either one of the first flange and the shaft encircling member, and a lubrication medium. An end of the region where the radial dynamic pressure generating groove is formed and which is distant from the second flange is located outwardly of the region where the first thrust dynamic pressure generating groove is disposed in the axial direction.

Abstract: There is provided a spindle motor including a sleeve rotatably supporting a shaft, a rotor coupled to an upper end of the shaft and rotating together with the shaft, a stopper part coupled to a main wall part protruding from one surface of the rotor and facing an outer peripheral surface of the sleeve, a cover plate coupled to the sleeve while maintaining a clearance between the cover plate and lower portions of the shaft and the sleeve, a base member coupled to the cover plate, and a stator holder fixedly disposed on the base member.

Abstract: A device having a directly driven rotating body (1), its circumference (11) being radially seated on radial bearings (4, 4?) in relation to the stationary body (2), and its at least one first face side (10) being axially seated in relation to the stationary body (2), wherein aerostatic bearings (5, 5?, 5?) are provided for the axial support mounting, characterized in that the first face side (10) has an annular magnet arrangement (32), which is configured coaxially to the axis of rotation (X) of the rotating body (1), and that the stationary body (2) has at least one electric coil arrangement (30), which is located opposite the annular magnet arrangement (32) in the axial direction and which forms together with the annular magnet arrangement (32) the components of an electrical direct drive (3) for the rotating body (1).

Abstract: A rotating hub and fixed spindle assembly with first and second fluid dynamic journal bearings and first and second fluid dynamic thrust bearings for a disc drive memory system has a pump seal and a radial ring seal at a first axial terminus for lubricant containment, and a capillary seal and a labyrinth seal at a second axial terminus for lubricant containment and storage. Lubricant fluid pressure differences between first and second seals are minimized through one or more lubricant fluid communicating channels in the hub assembly, in order to minimize lubricant fluid loss through a seal. Lubricant fluid can also be purged of any air bubbles by lubricant fluid circulation through the channel.

Abstract: A disk drive device includes a rotating body that rotates and drives a disk, a stationary body which includes a chassis with a protrusive part and a stator core fastened with the chassis, and a fluid bearing unit. The chassis has a recess with a bottom provided in the protrusive part, and the fluid bearing unit includes an insertion part inserted in the recess with the bottom, and a core encircled part. A gas passage is provided which causes a clearance space between the insertion part and the recess with the bottom to be in communication with a disk retaining space.

Abstract: A bearing apparatus according to a preferred embodiment of the present invention includes a bearing portion having a bottom and being substantially cylindrical; a shaft inserted in the bearing portion, and arranged to rotate about a central axis relative to the bearing portion; a bearing opposing portion defined in one piece, arranged above the bearing portion, and arranged to hold an upper end portion of the shaft while covering an outer circumferential surface upper portion and an upper end surface of the shaft; and a cylindrical seal portion arranged to extend downward from the bearing opposing portion. An inner circumferential surface of the cylindrical seal portion and an outer circumferential surface of the bearing portion are arranged to together define a seal gap therebetween, the seal gap including a seal portion having a surface of a lubricating oil defined therein.

Abstract: In the method for manufacturing a fluid dynamic bearing, the fluid dynamic bearing that lubricant is not injected into is prepared in a predetermined work space. The pressure in the work space is reduced. A delivery nozzle that delivers the lubricant is inserted into the storage region. The lubricant is delivered in the storage region so that the lubricant does not spill over from the storage region. The pressure in the work space is restored. Another way is that a lubricant is ejected after an oil repellent region for preventing the lubricant from leaking out is covered.

Abstract: There is provided a spindle motor including: a fluid dynamic pressure bearing assembly; a base member coupled to the fluid dynamic pressure bearing assembly; and a core fixedly coupled to the base member and having a coil wound therearound, wherein the base member has a disk portion and a coupling portion extending from an inner edge of the disk portion upwardly in an axial direction, one surface of the core is in contact with an outer circumferential surface of the overall coupling portion, and an upper end of the coupling portion is protruded upwardly, relative to an upper surface of the core.

Abstract: A lubricating oil is arranged between stationary and rotating portions of a spindle motor. When the motor is stationary, upper and lower surfaces of the lubricating oil are respectively located in upper and lower capillary seal portions. A first angle defined between an outer circumferential surface of the plate portion and an inner circumferential surface of a cylindrical portion at the upper capillary seal portion, and a second angle defined between an outer circumferential surface of a sleeve and an inner circumferential surface of the wall portion at the lower capillary seal portion, in a section taken along a plane including a central axis is respectively in the range of about 1 degree to about 8 degrees and in the range of about 1 degree to about 10 degrees, respectively. The upper capillary seal portion has maximum radial and axial dimensions smaller than those of the lower capillary seal portion.

Abstract: There is provided a hydrodynamic bearing assembly including a sleeve; and a shaft rotatably inserted into a shaft hole and constituting a bearing clearance, wherein at least one of an inner circumferential surface of the sleeve and an outer circumferential surface of the shaft includes upper and lower radial dynamic pressure grooves having a herringbone pattern, and conditional expressions a+b>c+d and b?a>c?d>0 are satisfied.

Abstract: There are provided a fluid dynamic pressure bearing assembly, a spindle motor including the same, an electronic blower including the same, and a vacuum cleaner including the same. The fluid dynamic pressure assembly includes: a shaft fixedly installed on a base member; and a sleeve having an axial hole fixed to an outer circumferential surface of the shaft and rotatably supported by fluid dynamic pressure, wherein when the sleeve is inclined, based on an axial direction while being rotated, the sleeve comes into line-contact or surface-contact with the shaft in the axial direction.

Abstract: Provided is a fluid dynamic bearing device, which fixes a lid member (10) to a bracket (6) or forms the lid member (10) and the bracket (6) integrally so that the bracket (6) exerts the release resistance of the lid member (10). As a result, the fluid dynamic bearing device can alleviate a fixing force required between a housing (7) and the lid member (10) or can make their fixture unnecessary, to thereby maintain the release resistance of the lid member (10) irrespective of a material of the housing (7).

Abstract: A fluid bearing apparatus includes a housing 7 which has a cylindrical shape having a fixing face 7c for fixing the outer circumferential surface 8b of a bearing sleeve 8, and axial circulation grooves 7d for bringing both end faces 8c, 8d of the bearing sleeve 8 into circulation on the inner periphery by forging. A groove molding portion 18a2 is provided on the outer circumference of a rod 18 which serves as a forming mold for the inner periphery of the housing 7, and the circulation grooves 7d are formed by forging with this groove molding portion 18a2. Moreover, after a sealing face 107d and a cylindrical outer circumferential surface 107e provided on the outer periphery of the housing 107 are formed by forging, an inner circumferential surface 107c is formed by forging.

Abstract: A rotating device includes a shaft body that has a shaft, a first flange extending outwardly from the outer periphery of the shaft, and a second flange, a bearing body that has a shaft encircling member encircling the shaft between the first flange and the second flange, a first thrust opposing part formed between the shaft encircling member and the first flange, a second thrust opposing part formed between the shaft encircling member and the second flange, an intermediate space provided in a gap between the shaft and the shaft encircling member, a radial dynamic pressure bearing, a first communication channel that allows the first thrust opposing part to be in communication with the intermediate space, and a second communication channel that allows the second thrust opposing part to be in communication with the intermediate space.

Abstract: A typical dynamic bearing design comprises a ring shaped or circular thrust plate mounted at or near the end of a shaft, the shaft defining together with a surrounding sleeve a journal bearing by providing grooves on only one of the two surfaces facing the gap between the shaft and sleeve. On the ring shaped thrust plate supported by the shaft, the traditional upward thrust bearing defined between the lower face of the thrust plate and the facing surface of the sleeve is maintained; but no grooves are on the surface of the thrust plate distant from the shaft and a facing counterplate surface. Further, the journal bearing is defined to have an asymmetry so that a bias force pressure along the surface of the shaft toward the thrust plate is established.

Abstract: An air bearing shaft for an air cycle machine is provided. The air bearing shaft includes a seal disk and a shaft body. The shaft body includes a first shaft body portion extending from a face of the seal disk to a knife-edge seal. The first shaft body portion includes journal bearing cooling holes positioned axially closer to the knife-edge seal than to the face of the seal disk. The journal bearing cooling holes extend through the first shaft body portion to a hollow interior and have a total cooling area. Start-up holes are positioned axially closer to the face of the seal disk than to the knife-edge seal. The start-up holes extend through the first shaft body portion to the hollow interior. The start-up holes have a total start-up area. A ratio of the total cooling area to the total start-up area is between 2.17 and 4.06.

Abstract: An apparatus includes a stationary shaft and a sleeve rotatable with respect to the shaft. A fluid dynamic bearing is defined by the stationary shaft and the sleeve. A fluid channel includes a first axially extending portion in the fluid dynamic bearing, and a radially extending portion extending radially outward from the first axially extending portion. In addition the fluid channel includes a second axially extending portion extending axially downward from the radially extending portion. The apparatus further includes a pump seal including grooves formed in the second axially extending portion.

Abstract: A bearing apparatus includes an upper annular portion that has a circular or substantially circular ring shape, and is arranged to project radially outward from a stationary shaft. One of an upper surface of a sleeve and a lower surface of the upper annular portion includes a first pumping groove array arranged to send a lubricating oil radially inward. The sleeve includes a second inner circumferential surface arranged radially outside of the upper annular portion. One of a lower surface of a cap, an upper surface of the upper annular portion, the second inner circumferential surface, and an outer circumferential surface of the upper annular portion includes a second pumping groove array arranged to send the lubricating oil radially outward or axially downward.

Abstract: There are provided a hydrodynamic bearing assembly and a spindle motor including the same. The hydrodynamic bearing assembly includes: a sleeve including a shaft hole to have a shaft rotatably installed therein; and a cover member covering the shaft hole at a lower portion of the shaft hole in an axial direction, wherein an inner surface of the sleeve is provided with depression parts depressed in an outer diameter direction between upper and lower portions of the sleeve and portions in which radial bearings are formed, such that the portions in which the radial bearings are formed are provided with bearing closure adhesion parts allowing the portions in which the radial bearings are formed to be closer to the shaft than portions other than the portions in which the radial bearings are formed.

Abstract: A rotating hub and fixed spindle assembly with first and second fluid dynamic journal bearings and first and second fluid dynamic thrust bearings for a disc drive memory system has a pump seal and a radial ring seal at a first axial terminus for lubricant containment, and a capillary seal and a labyrinth seal at a second axial terminus for lubricant containment and storage. Lubricant fluid pressure differences between first and second seals are minimized through one or more lubricant fluid communicating channels in the hub assembly, in order to minimize lubricant fluid loss through a seal. Lubricant fluid can also be purged of any air bubbles by lubricant fluid circulation through the channel.

Abstract: A rotating device includes a fluid dynamic bearing unit. The fluid dynamic bearing unit includes a shaft encircling member that encircles a shaft, an intermediate encircling member that encircles the shaft encircling member, a shaft holder formed with a shaft hole into which an end of the shaft is fitted to fix the shaft, a base-side encircling member fixed to the shaft holder and encircling the intermediate encircling member, and a ring member fixed to the intermediate encircling member and encircling a rod encircling member. A lubricant is present between a rotating body and a fixed body. A first air-liquid interface is present between the base-side encircling member and the intermediate encircling member, and a second air-liquid interface is present between the ring member and the rod encircling member.

Abstract: A low-cost shaft member for hydrodynamic bearing apparatuses restores the pressure balance in a thrust bearing gap formed on both axial sides of the flange portion in an early stage. A shaft material integrally having a shaft portion and a flange portion with a through-hole between both end faces of the flange portion is formed in a common forging step. As a result, the through-hole is formed to open to an inner diameter side of the bearing gaps avoiding the thrust bearing gaps formed on both end faces of the flange portion of the shaft member as a finished product.