Abstract: A bearing apparatus includes a cylindrical bearing portion; a cap member; a cylindrical holder; a shaft; and a thrust plate. The holder includes an increased diameter portion. The bearing portion includes a plate accommodating portion. An outer circumferential surface of the plate accommodating portion is arranged to have a diameter greater than a diameter of an outer circumferential surface of a portion of the bearing portion which is on an upper side of the plate accommodating portion. The distance between the outer circumferential surface and an inner circumferential surface of the plate accommodating portion is arranged to be smaller than the distance between the outer circumferential surface and an inner circumferential surface of the portion of the bearing portion which is on the upper side of the plate accommodating portion. A thrust dynamic pressure bearing portion is defined in a thrust gap.

Abstract: In a disk drive device, a hub has an outer circumferential wall portion configured to hold a recording disk. A base member has a cylindrical portion, whose central axis is the rotation axis of the hub, on a surface on the side of the hub. A fluid dynamic bearing holds a lubricant and rotatably supports the hub relative to the base member. A ring-shaped attraction plate including a magnetic material is fixed to the base member and faces a magnet in the axial direction. The outer circumferential wall portion is configured such that the outer circumferential wall portion surrounds the attraction plate and that the range of the outer circumferential wall portion in the axial direction overlaps with the range of the attraction plate in the axial direction.

Abstract: A sleeve supports a shaft. A housing member is arranged so as to surround the sleeve and make the end of the sleeve protrude. A base member holds the housing member and fixes a stator core so as to surround the housing member. A hub drives a recording disk by being rotated integrally with the shaft, with a magnet being fixed to an annular portion concentric with the shaft so as to face the stator core fixed to the base member. A thrust member is rotated integrally with the hub, and a descender portion and a ring portion.

Abstract: Fixation strength of a bearing sleeve with respect to a housing is increased so that stable bearing performance can be achieved. A fluid dynamic bearing device (1) includes a housing (7) and a bearing sleeve (8) fixed to an inner periphery of the housing (7). The housing (7) and the bearing sleeve (8) have therebetween a press-fitting part (10) at which the housing (7) and the bearing sleeve (8) are fixed by press-fitting, and an adhesive-filled part (11) formed on an opening side with respect to the press-fitting part (10).

Abstract: Disclosed herein is a spindle motor having a fluid dynamic bearing as an oil gap formed between a rotator and a stator, wherein the stator includes a sleeve having a protruding part extending in a circumferential direction formed on the upper part thereof, the rotator includes a hub including an oil interface forming member positioned under the protruding part of the sleeve and coupled to the lower end thereof, and an oil interface of the oil gap is formed between the upper part of the oil interface forming member and the lower part of the protruding part of the sleeve.

Abstract: A fluid dynamic bearing includes a shaft to which a resin flange is fixed by insert molding. The process where the flange is fixed to the shaft by insert molding includes a flange forming process in which the flange, fixed to the shaft, is formed by injecting the resin into a filled portion in the lower mold through an upper mold, while cooling at least part of the shaft, arranged in a shaft arrangement portion in a lower mold, with cooling water circulating through a cooling pipe.

Abstract: There is provided a bearing assembly including: a sleeve supporting a shaft and including a circulation hole through which oil is circulated; a thrust plate coupled to the shaft and generating dynamic pressure in the oil; and a base cover coupled to the sleeve to thereby close a lower portion of the sleeve, wherein the oil passes through the circulation hole and is then supplemented between the thrust plate and the base cover in order to suppress bubblegeneration due to leakage of the oil filled between the thrust plate and the base cover at the time of rotation of the shaft.

Abstract: An oil film is formed in a radial bearing clearance of a first radial bearing portion (R1) and a second radial bearing portion (R2) so as to rotatably support a shaft member (2). A bearing sleeve (8) and the shaft member (2) are accommodated in a housing (7), and the housing (7) has an inner space filled with a lubricant oil and has an opening sealed by a seal member (9). A first seal space (S1) is formed by means of an inner peripheral surface (9a2) of the seal member (9). The housing (7) and the seal member (9) are formed through injection molding of a resin.

Abstract: When a bearing member (bearing sleeve (8)) is formed of a sintered metal comprising a middle relief portion (E), a lubricating oil can be impregnated and retained in inner pores of the sintered metal. Thus, when the lubricating oil in a middle relief space (E0) is drawn into a radial bearing gap side and lubricating oil pressure in the middle relief space (E0) decreases, the lubricating oil impregnated in the inner pores of the bearing sleeve (8) is drawn out from surface pores of the middle relief portion (E) and supplied into the middle relief space (E0). Thus, generation of negative pressure is prevented.

Abstract: A bearing unit for a disk drive device is formed by a sleeve concave portion and a shaft concave portion, and is provided with a capillary seal portion in which the gap between the sleeve concave portion and the shaft concave portion is increased in diameter toward the hub side of the sleeve. Assuming that: the outer circumferential diameter at the tilt starting end on the base member side of the shaft concave portion is D0; the inner circumferential diameter at the tilt starting end on the hub side of the sleeve concave portion is D1; the facing outer circumferential diameter of the shaft concave portion, which faces, in the radial direction, the inner circumference at the tilt starting end of the sleeve concave portion, is D2; and the diameter of the most concave inner circumference of the sleeve concave portion is D3, D2 is smaller than D0, D3 is larger than D1, and the difference between D3 and D0 is larger than that between D0 and D2.

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 dynamic bearing device allows production of a smaller housing at low cost and suppresses ion elution from the resin portion to thereby maintain cleanliness in the dynamic bearing device and exert a desired bearing performance. A dynamic bearing device 1 is equipped with a bearing sleeve 8 fixed to the inner periphery of the housing 7, and a rotary member rotatable relative to the bearing sleeve 8 and the housing 7, in which the rotary member is supported in the radial direction and the thrust direction in a non-contact manner by a dynamic pressure action of a lubricant fluid generated in a bearing clearance. The housing 7 is formed by injection molding of a resin composition containing polyphenylene sulfide (PPS) as the base resin and PAN type carbon fibers as a filler.

Abstract: There are provided a hydrodynamic bearing assembly capable of increasing a storage amount of oil and preventing evaporation or leakage of the oil by increasing a length of a sealing part, and a motor including the same. The hydrodynamic bearing assembly includes: a sleeve supporting a shaft such that an upper end of the shaft protrudes upwardly in an axial direction; a sleeve housing provided to enclose an outer peripheral surface of the sleeve, and forming an oil interface between an inner peripheral surface thereof in an outer diameter direction and a main wall part protruding downwardly in the axial direction from a rotor case inserted into the upper end of the shaft; and a cover member provided in lower portions of the shaft and the sleeve and coupled to the sleeve housing while having a clearance therebetween.

Abstract: A spindle motor including: a lower thrust member fixedly coupled to a base member; a shaft fixedly coupled to at least one of the lower thrust member and the base member; a sleeve disposed on an upper portion of the lower thrust member and rotatably installed on the shaft; a rotor hub coupled to the sleeve to thereby rotate together with the sleeve; an upper thrust member fixedly coupled to an upper end portion of the shaft and forming a liquid-vapor interface together with the sleeve; and a cover member fixedly coupled to the shaft so as to be disposed on an upper portion of the upper thrust member, wherein the upper thrust member includes a stepped jaw part having a lower surface supported by an upper surface of the shaft and an upper surface pressed by the cover member, so as to increase coupling strength with the shaft.

Abstract: A shaft member for a fluid dynamic bearing device that has a recess to cause a dynamic pressure effect of a fluid in a bearing clearance, which is formed on it by rolling, and where a surface layer portion of the recess and a surface layer portion of a surrounding region of the recess has a nitride layer, and where nitrogen is diffused and penetrated in a material of the shaft member that is formed by nitriding after the rolling.

Abstract: A bearing unit includes: a shaft; a radial bearing configured to support the shaft in a circumferential direction; a thrust bearing configured to support one end of the shaft in a thrust direction; a housing having the radial bearing and the thrust bearing disposed in the inside and having a closed structure except a shaft insertion hole into which the shaft is fitted; a coming out preventing member provided on one end side of the radial bearing at which the thrust bearing is provided configured to prevent the shaft from coming out from the radial bearing; and viscous fluid filled in the housing. The coming out preventing member is made of a resin material having a value of a Young's modulus equal to or higher than 3.4 GPa.

Abstract: A fluid dynamic bearing apparatus includes shaft member 2, housing 7, sleeve portion 8, and sealing portions 9, 10. The housing 7 includes a straight cylindrical inner circumferential surface with a constant diameter and openings at both axial ends thereof. The sleeve portion 8 is provided separately from the housing 7 and fixed to the inner circumferential surface of the housing 7. A radial bearing gap is formed between the inner circumferential surface 8a of the sleeve portion 8 and the outer circumferential surface 2a of the shaft member 2 , and thrust bearing gaps are formed between the end faces 9b, 10b of the sealing portions 9, 10 and the end faces 8b, 8c of the sleeve portion 8 opposing these to support the shaft member 2 in a non-contact manner in the radial direction and in the thrust direction by the hydrodynamic effect of a lubricating oil produced in each bearing gap.

Abstract: A device for providing an air-gap associated with a portion of a fluid dynamic bearing, a sleeve is provided and surrounds a portion of a shaft. The sleeve and the shaft are configured for establishing the air-gap proximal to a portion of the fluid dynamic bearing. In addition, a cap is also provided and coupled to the sleeve. The cap has an outer end proximal to a portion of the fluid dynamic bearing such that the air-gap is provided between the outer end of the cap and the portion of the fluid dynamic bearing, wherein the air-gap forms a labyrinth seal.

Abstract: The fluid dynamic bearing system has at least one stationary part, and at least one rotating part that is supported rotatable about a rotational axis with respect to the stationary part. A bearing gap filled with bearing fluid is formed between mutually opposing surfaces of the stationary and of the rotating part. The bearing system includes at least one fluid dynamic radial bearing and at least one fluid dynamic axial bearing that are disposed along sections of the bearing gap. In one aspect of the invention, an annular sealing gap for sealing open ends of the bearing gap has one end connected to the bearing gap and one end connected to an annular reservoir, the outside radius of the reservoir measured from the rotational axis being larger than the outside radius of the sealing gap.

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 bearing apparatus includes a shaft, a thrust cup including an annular potion and a cylindrical portion, a rotating member including a through hole defined therein, and a lubricating oil. A second gap defined between a lower surface of the rotating member and an upper surface of the annular portion of the thrust cup includes a first region in communication with a capillary seal portion, and a second region positioned radially inward of the first region and having an axial dimension smaller than that of the first region. A lower end portion of the through hole is open at a location radially outwardly away from a boundary between the first and second regions, so that a local circulation of the lubricating oil arises within the first region during rotation of the rotating member.

Abstract: Providing a fluid dynamic bearing device, wherein the outer member comprises a member formed by a pressing process on a plate member, the radial bearing surface and at least the one of the thrust bearing surfaces of the outer member being formed by the pressing process, and wherein at least a part of the inner member, which forms the radial bearing surface and the thrust bearing surfaces of the inner member, is made of a sintered metal.

Abstract: A spindle motor includes a shaft arranged in an upward/downward direction along a central axis; a base member including a substantially cylindrical holder portion arranged around the central axis; a bearing unit arranged radially inward of the holder portion; and a rotating portion arranged above the base member to rotate about the central axis. The rotating portion preferably includes a mounting surface on which a disk is to be mounted. An adhesive containing an electrically conductive material and an adhesive containing an externally stimulated curing material and/or an anaerobic curing material are arranged in a clearance space defined between an inner circumferential surface of the holder portion and an outer circumferential surface of the bearing unit. The adhesive containing the electrically conductive material is arranged above the adhesive containing the externally stimulated curing material and/or the anaerobic curing material.

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: Disclosed herein are a bearing assembly and a spindle motor including the same. The bearing assembly includes: a shaft having a first magnet formed on an outer circumferential surface thereof; and a sleeve having a second magnet formed on an inner circumferential surface thereof, and spaced apart from the first magnet to face the first magnet, the sleeve supporting the shaft, wherein a spaced gap between the first magnet and the second magnet is filled with oil. According to the present invention, power consumption due to driving of the spindle motor can be reduced by using the bearing assembly included in the magnetic bearing.

Abstract: A fluid bearing motor. The fluid bearing motor includes a stationary sleeve, a backiron, a hub coupled to the backiron, and a gap forming component. The hub is operable to rotate with respect to the stationary sleeve. The gap forming component is attached to the stationary sleeve and forms a gap between the stationary sleeve and the backiron. The size of the gap dynamically changes in response to changes in temperature.

Abstract: A robust spindle motor is provided having improved shock resistance for fluid containment, as well as enhanced air purging characteristics. In an aspect, axial displacement of relatively rotating components is restricted by utilizing a limiter situated adjacent to a limiter bushing forming an axial limiter gap therebetween. A fluid channel, at least partially diverging, extends from a hydrodynamic bearing to the axial limiter gap, and continues to a region beyond the axial limiter gap. In an aspect, an axially diverging slot is situated adjacent to the axial limiter gap. Power is reduced by reducing viscous drag between relatively rotating components, hydrodynamic bearing length is increased, and higher stiffness of the hydrodynamic bearing is provided. Fluid volume may be increased, thereby offsetting fluid evaporation losses and allowing for the use of lower viscosity lubricants.

Abstract: A thinner fluid dynamic bearing capable of stable shaft rotation, a motor including the bearing, and a recording-medium driving apparatus including the bearing are provided. Pressure-generating grooves are provided in thrust surfaces of a thrust bearing portion 39 opposite a circular plate 35 and a stopper 33 to attract a working fluid from inner and outer edges of the thrust bearing portion 39 to a radially midway portion thereof as a shaft member 16 rotates relative to a support 22. One or more through-holes 48 are provided between inner edges of annular regions of the thrust surfaces in which the pressure-generating grooves are provided and the midway portion in the radial direction. The through-holes extend through the thrust bearing portion 39 in a central-axis direction of the shaft member.

Abstract: A protrusion (7b3) directed axially downwards is provided at a bottom portion (7b) of a housing (7), and an outer peripheral surface (7b31) of the protrusion (7b3) is fixed to an inner peripheral surface (6a) of a bracket (6). When a thrust load is applied to the bottom portion (7b) of the housing (7), a part of the load is supported by the bracket (6) via the protrusion (7b3). Thus, a strength of a boundary portion (P) between a side portion (7a) and the bottom portion (7b) of the housing (7) increases, making it possible to prevent rupture of the boundary portion (P) due to an excessive thrust load. On the other hand, a wall thickness of the bottom portion (7b) can be made invariable, so it is possible to suppress deformation through molding shrinkage of a thrust bearing surface formed on an inner end surface (7b1) of the bottom portion (7b).

Abstract: A groove configuration that improves angular stiffness in a fluid dynamic bearing is provided. A primary groove and a secondary groove are formed on a journal bearing or thrust bearing surface. The secondary groove apex induces a heightened pressure response at a localized area to counteract angular displacement. The primary groove extends a greater circumferential distance about the bearing surface as compared to the secondary groove. The secondary groove apex is also situated closer to an axial end of the journal bearing, or closer to an outer diameter of the thrust bearing, as compared to the primary groove apex. Bearing wear is prevented or minimized under gyroscopic loading. The improved angular stiffness may result in the heads of a storage device being accurately aligned with disc storage tracks. Discs may thus be designed with increased track densities, allowing for smaller discs and increased storage capacity of discs.

Abstract: The present invention aims to achieve a reduction in cost for a fluid dynamic bearing device. The fluid dynamic bearing device supports a shaft member (2) radially in a non-contact fashion by a dynamic pressure action generated in a radial bearing gap between an outer peripheral surface of the shaft member (2) and an inner peripheral surface (7a) of a bearing member (7), and is composed of the shaft member (2), the bearing member (7), a cover member (8), and a seal member (9). The shaft member (2) is inserted into an inner periphery of the bearing member (7), and an opening at a lower end thereof is sealed by the cover member (8). The seal member (9) is attached to an opening at an upper end of the bearing member (7), forming a seal space (S) between itself and the outer peripheral surface of the shaft member (2). Dynamic pressure grooves (G) of radial bearing portions (R1 and R2) are formed in an inner peripheral surface (7a) of the bearing member (7) by molding.

Abstract: There is provided a roll machining apparatus for machining the surface of a roll, which can accurately support a roll by hydrostatic bearings while absorbing thermal expansion of the roll in the length direction, thus enhancing the machining precision. The roll machining apparatus can include a first hydrostatic radial bearing for receiving the radial load of a first spindle and rotatably supporting the first spindle, a hydrostatic thrust bearing for receiving the thrust load of the first spindle and limiting axial movement of the first spindle, a second hydrostatic radial bearing for receiving the radial load of a second spindle and rotatably supporting the second spindle, and a floating thrust having a thrust bearing for receiving the thrust load of the second spindle. The floating thrust selectively limits and permits axial movement of the thrust bearing.

Abstract: Disclosed herein are a hydrodynamic bearing assembly and a motor including the same. The hydrodynamic bearing assembly includes: a sleeve supporting a shaft; and a sleeve housing combined with the sleeve to prevent the leakage of oil; and at least one stepped part formed on at least one of the sleeve and the sleeve housing in order to align an axis of the sleeve with an axis of the shaft and provide a bonding space with the sleeve therebetween.

Abstract: A shaft portion is press-fitted to a flange portion, and a plastic working portion of a first jig is pressed against an upper end surface of the flange portion, whereby the flange portion is partially subjected to plastic deformation toward an inner peripheral side. With this, a caulked portion is formed between the flange portion and the shaft portion. Further, press-fitting and caulking are performed in a state in which both end surfaces of the flange portion are bound by a second jig and a third jig.

Abstract: A sleeve supports a shaft. A housing member is arranged so as to surround the sleeve and make the end of the sleeve protrude. A base member holds the housing member and fixes a stator core so as to surround the housing member. A hub drives a recording disk by being rotated integrally with the shaft, with a magnet being fixed to an annular portion concentric with the shaft so as to face the stator core fixed to the base member. A thrust member is rotated integrally with the hub, and a descender portion and a ring portion.

Abstract: Channels and gaps inside a bearing mechanism are filled with lubricating oil, and the lubricating oil is retained in a first tapered seal portion arranged radially outward of a sleeve, and a second tapered seal portion arranged between the shaft and an upper cap placed above the sleeve. An arrangement of groove-shaped recessed portions on an inner circumferential surface of the upper cap and raised portions on a lower surface of a top portion thereof contributes to increasing a channel cross-sectional area of a channel provided between the upper cap and the sleeve to connect the first tapered seal portion with the second tapered seal portion.

Abstract: There is provided a hydrodynamic bearing assembly including: a sleeve having a shaft inserted thereinto and supported thereby; a thrust plate coupled to one end of the shaft; an extension part formed at the thrust plate to be extended in an axial direction so as to be coupled to the shaft; and a coupling part formed at the shaft to contact an inner surface of the extension part so as to be coupled to the extension part.

Abstract: A rotating device includes a fixed body having a base and a shaft, a hub, and a rotating body having a rotating-body-side encircling member fixed to the hub and encircling the shaft. A lubricant is present between the fixed body and the rotating body. The rotating-body-side encircling member and the shaft are each formed with a radial dynamic pressure generating groove. The fixed body includes a base-side encircling member having a disk part encircling the base-side portion of the shaft and a cylinder part encircling the rotating-body-side encircling member. The base-side encircling member has the disk part fixed to the shaft by interference fitting, and has the cylinder part fixed to the base. An air-liquid interface is located in a gap in the radial direction between the inner periphery of the cylinder part and the outer periphery of the rotating-body-side encircling member.

Abstract: A fluid dynamic pressure bearing includes a shaft arranged along a central axis, an annular member fixed to the shaft, a sleeve, a lubricant, and a lubricating film. A stepped surface is provided on the outer circumferential surface of the shaft. The annular member preferably includes a lower surface extending radially with respect to the central axis and arranged to make contact with the stepped surface in the inner edge portion of the lower surface. The sleeve preferably includes an upper surface axially opposed to the lower surface of the annular member. The lubricant is provided between the shaft and the sleeve and between the annular member and the sleeve. The lubricating film is provided on the lower surface of the annular member at least over a region lying radially outwardly of the inner edge portion of the lower surface.

Abstract: A fluid dynamic bearing device includes a bearing sleeve including a radial bearing surface, a shaft member to be inserted to an inner circumference of the bearing member, and a radial bearing part for non-contact supporting the shaft member in a radial direction by a dynamic pressure action of a fluid generated in a radial bearing gap between the radial bearing surface of the bearing member and an outer circumferential surface of the shaft member. Additionally, a plurality of bearing sleeves are axially arranged, and each bearing sleeve is formed having different axial length with respect to one another.

Abstract: A motor includes a housing, a rotor and a stator. The housing includes a shaft tube having a free end. The rotor includes a shaft rotatably extending through the bearing and having an annular groove. The stator includes an assembling hole receiving the shaft tube. The stator includes an upper bobbin, a lower bobbin, a plurality of silicon steel plates and a winding. The upper bobbin includes a plurality of pressing plates annularly, each having first and second abutting portions. The first abutting portion has a first end connecting to the upper bobbin, and a second end abutting against a top surface of the bearing. The free end is lower than the first end but higher than the second end. The first abutting portion is spaced from the shaft tube and abuts only on the bearing. The second abutting portion extends from the first abutting portion into the annular groove.

Abstract: An air cycle machine has a housing which holds a compressor section, and a turbine section having an expansion area, and a fan section disposed outside of the housing. A shaft, which attaches to and is coaxial with the compressor section, the turbine section and the fan section, is supported by an air journal bearing and an air thrust bearing. The shaft has a hollow core for porting cooling air from the air journal bearing and the air thrust bearing, and a tube that extends into said expansion area and communicates cooling air from the turbine expansion area to the thrust bearing.

Abstract: A lid member (10) is formed in a cup-like shape while having a plate portion (10a) and a cylindrical fixed portion (10b) axially protruding from an outer peripheral end of the plate portion (10a). An outer peripheral surface (10b1) of the fixed portion (10b), which serves as a fixation surface (B), is fixed to an inner peripheral surface (7a) of a housing (7) as an outer member (A). An axial dimension of the fixation surface (B) is larger than a thickness of the plate portion (10a), and hence it is possible to thinly-form the plate portion (10a) and to increase a fixing force between the lid member (10) and the housing (7). As a result, an axial dimension of a fluid dynamic bearing device can be reduced and durability thereof can be simultaneously increased.

Abstract: A fluid dynamic bearing formed by a microelectromechanical systems (MEMS) wafer-level batch-fabrication process is provided. The process results in a high performance and high reliability fluid dynamic bearing having features including higher bearing lifetime at high RPM, improved bearing stiffness, durability and thrust/restoring forces capabilities. The present invention is especially useful with small form factor disc drive memory devices having constraints in motor height, such as a 2.5 inch disc drive, requiring high performance including high rotational speed and large areal density. A sacrificial layer is utilized in the process to simultaneously form symmetrical facing surfaces of relatively rotatable components. The facing surfaces define, therebetween, a desired feature, such as a journal bearing, a thrust bearing, a fluid channel, a fluid reservoir, a capillary seal, pressure generating grooves, and other profile geometries.

Abstract: In a method for manufacturing a rotor hub for use in a spindle motor, free-cutting stainless steel is used as a material of the rotor hub. A slug of free-cutting stainless steel is subjected to a plastic working to form a disk mounting portion and a cylindrical surface positioned radially inwardly of the disk mounting portion. Then, a cylindrical disk fitting surface is formed by machining substantially the entirety of the cylindrical surface. The rotor hub contains A-type inclusions appearing in a cross section taken along a center axis of the disk mounting portion. The A-type inclusions are oriented in directions different than the center axis.

Abstract: The invention relates to a fluid dynamic bearing system that comprises at least one stationary part that has a shaft and two bearing plates disposed on the shaft at a mutual spacing, and at least one rotating part that is supported so as to rotate about a rotational axis with respect to the stationary part, and comprises a bearing bush and a sleeve enclosing the bearing bush. A bearing gap filled with bearing fluid is provided between the parts and at least one sealing gap for sealing the bearing gap that extends concentric to the rotational axis. The bearing comprises at least one fluid dynamic radial bearing and two fluid dynamic axial bearings and at least one recirculation channel that connects the two axial bearing regions to each other.

Abstract: A fluid dynamic bearing device includes a housing injection molded with a bearing sleeve as an insert. Accordingly, the molding of the housing and the assembly of the housing and the bearing sleeve can be performed in a single step. In addition to this, by simply increasing the die precisions the housing and the bearing sleeve can be fixed easily with high precision. Since the housing is opened at both ends, it is possible to sandwich the bearing sleeve, and accordingly, the bearing sleeve can be accurately positioned inside the dies with reliability.

Abstract: Disclosed is a hydrodynamic bearing assembly including: a rotary member fixed to a shaft and rotating in linkage with the shaft; and a sleeve supporting the shaft, wherein a coating film is formed by spraying, at high pressure, a solid lubricant having a single component onto one surface of at least one of the sleeve and the rotary member corresponding to the sleeve.

Abstract: A turbomachine has a shaft mounted in a shaft housing, and a rotor in a rotor housing at one end of the shaft, for compression, expansion, or transport of a working gas. The shaft is mounted by hydrostatic, gas-lubricated bearings that have a connector to a compressed gas line that is connected with a pressure region of the turbomachine. A portion of the gas that is passed from the pressure region is applied to the bearing. The shaft is mounted so that the bearing effect is at least extensively independent of the rotational speed of the shaft, thereby guaranteeing support of the shaft during startup of the turbomachine, and good rigidity and low sensitivity to pressure surge stresses. The pressure in the connector to the compressed gas line is at least 5 bar greater than the pressure in the region of the ventilation connector.

Abstract: A device is provided having a support structure and a rotating shaft having a center axis which rotating shaft and support structure are pivotable supported against each other by at least one hydrodynamic rotary bearing including a first bearing part and a second bearing part pivotable relatively to each other, a lubricant and a contact zone between the first bearing part and the second bearing part at least when the hydrodynamic rotary bearing is at rest, wherein the rotating shaft and the support structure are shaped in such a way and the hydrodynamic rotary bearing is in such a way arranged on the rotating shaft and the support structure that the contact zone of the hydrodynamic rotary bearing is submerged in the lubricant even when the hydrodynamic rotary bearing is at rest.