Abstract: An example apparatus includes a pointing structure, a magnetic-contrast bearing, and drive circuitry. The magnetic-contrast bearing is coupled to the pointing structure, and includes a magnetic array and a substrate that is arranged with the magnetic array. The drive circuitry generates a magnetic field that interacts with the magnetic array and causes control of a pointing position of the pointing structure.

Abstract: A gas dynamic bearing includes a shaft extending along a central axis extending vertically, and a sleeve with a hole opening at least at one end of the sleeve in an axial direction, at least a portion of the shaft housed inside the hole. The sleeve includes dynamic pressure grooves in an inner peripheral surface of the hole. The shaft includes a core portion, and a protective portion that is disposed on an outer peripheral surface of the core portion and that includes at least a portion facing the inner peripheral surface of the hole in a radial direction. The protective portion includes a first protective portion and a second protective portion. The first protective portion is at least above or below the second protective portion in the axial direction, and includes at least a portion with a thickness in the radial direction more than a thickness of the second protective portion in the radial direction.

Abstract: A hydrodynamic bearing assembly includes a first stationary component, a shaft coupled to the first stationary component, and a second stationary component coupled to the shaft opposite the first stationary component. The hydrodynamic bearing assembly also includes a rotating component coupled to the shaft between the first stationary component and the second stationary component. The rotating component includes a first end surface including a first diameter and an opposing second end surface including a second diameter that is greater than the first diameter.

Abstract: Provided is a fluid dynamic bearing device (1), including: a bearing sleeve (8) made of sintered metal; a rotary member (2) including a shaft portion (21) and a hub portion (23); and first and second thrust bearing portions (T1, T2) that form thrust bearing gaps respectively on an upper end surface (8b) and a lower end surface (8c) of the bearing sleeve (8) along with rotation of the rotary member (2). At least an outer peripheral surface of the bearing sleeve (8) is subjected to pore sealing treatment. A sealing gap (S) for retaining an oil surface of lubricating oil is made along a tapered outer peripheral surface (8d1) of the bearing sleeve (8). A lid member (10) having a bottomed cylindrical shape being fixed to an outer periphery of a lower end of the bearing sleeve (8).

Abstract: A vane pump includes a rotor including a first annular groove and a second annular groove. The rotor further includes a cylindrical portion projecting axially from a radial inner side of the first annular groove and fitting over a drive shaft, and a slide contact portion formed on a radial inner side of the second annular groove. The cylindrical portion is slidably received in a bearing hole formed in a first side wall of a housing, whereas the slide contact portion abuts slidably on an inside wall surface of a second side wall of the housing. There is further formed, in the first annular groove, a recessed portion making a pressure receiving area of one of the first and second annular grooves greater than a pressure receiving area of the other of the first and second annular grooves.

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: In one example, an FDB motor having a shield member is provided. In one example, the method includes disposing a first member and a second member for relative rotation about an axis of rotation. An annular shield member is attached to the first member, the shield member disposed adjacent a fluid reservoir for containing a bearing fluid. The reservoir is filled through an aperture (e.g., a fill hole) in the shield member. Thereafter, the aperture is at least partially sealed. The aperture may be hermetically sealed via one or more laser pulses. In other examples, a two piece shield is provided for shielding a reservoir without a fill hole.

Abstract: A spindle motor includes a sleeve fixedly installed on a base member; a shaft rotatably supported by the sleeve; a rotor hub fixedly installed on an upper end portion of the shaft to rotate together therewith; and a thrust plate fixedly coupled to the sleeve so as to be disposed to face a lower surface of the rotor hub and having a ring shape. The thrust plate includes a channel part formed therein in order to reduce a difference in pressure between a bearing clearance on an inner side thereof and a bearing clearance on an outer side thereof. The channel part is configured of grooves formed in a lower surface of the thrust plate and an inner peripheral surface thereof.

Abstract: There are provided a hydrodynamic bearing assembly and a motor including the same. The hydrodynamic bearing assembly includes a sleeve rotatably supporting a shaft and including a first circulation hole formed therein, the first circulation hole penetrating between an inner peripheral surface thereof and an outer peripheral surface thereof; a sleeve housing into which the sleeve is inserted; and a second circulation hole formed between the outer peripheral surface of the sleeve and an inner peripheral surface of the sleeve housing to be in communication with the first circulation hole, wherein an upper portion of the second circulation hole has a larger diameter than a lower portion thereof in an axial direction.

Abstract: Provided herein is an apparatus, including a stationary component and a rotatable component; a fluid between the stationary component and the rotatable component; a limiter shoulder of the stationary component; a flanged limiter bushing of the rotatable component; and a separating means for separating the limiter shoulder and the limiter bushing, wherein the separating means comprises the fluid.

Abstract: A bearing mechanism includes a stationary portion and a rotating portion. The stationary portion includes a shaft portion and a plate portion. The rotating portion includes a sleeve including an annular portion, a cylindrical portion, an annular bottom surface, and a first communication hole. The rotating portion includes a ring member arranged to cover at least a portion of an opening of the first communication hole, and faces the plate portion via a first gap. A pumping groove array is disposed in the plate portion or the ring member. A second communication hole is disposed between the ring member and the annular bottom surface, and connected to the first communication hole. At least a portion of the opening of the second communication hole is positioned on a farther radial direction inner side than the pumping groove array.

Abstract: A rotating device includes a shaft body including a portion extending in an axial direction, and a bearing body which retains a part of the shaft body, is relatively rotatable to the shaft body, and is provided with a groove formed part having an inner circumference formed with a fluid dynamic pressure generating groove. The bearing body includes, at the groove formed part, a slanted plating layer having a plating thickness gradually becoming thick toward an external side in the axial direction.

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 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: Provided herein is an apparatus, including a stationary component and a rotatable component; a fluid between the stationary component and the rotatable component; a limiter shoulder of the stationary component; a flanged limiter bushing of the rotatable component; and a separating means for separating the limiter shoulder and the limiter bushing, wherein the separating means comprises the fluid.

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 rotating device includes: a rotating body, a fixed body and lubricant. A surrounding member in the fixed body has a sleeve and a housing for surrounding the sleeve. A first radial dynamic pressure generating groove and a second radial dynamic pressure generating groove are formed on at least one of the inner circumferential surface of the sleeve and the outer circumferential surface of a shaft in the rotating body. The sleeve has a flange portion protruding radially outward at the end portion of the sleeve near to a hub in the rotating body. A concave portion, which is made by axially concaving at least part of the area corresponding to a wall thickness of the sleeve on the inner circumference side of the flange portion, is circumferentially provided in the flange portion.

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 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 fixedly installed on the base member and having a circulation hole formed therein; a shaft rotatably inserted into a shaft hole of the sleeve; a rotor hub fixedly installed on an upper end portion of the shaft; and a thrust member installed in an installation groove of the sleeve and forming a connection part while being installed in the installation groove, the connection part being connected to the circulation hole, wherein the connection part is formed by the sleeve and the rotor hub and connects a sealing part in which a liquid-vapor interface is disposed and the circulation hole to each other, and an upper and lower radial dynamic grooves allowing a lubricating fluid to move from a lower end portion of the shaft toward the upper end portion thereof during rotation of the shaft.

Abstract: A bearing capable of satisfying demands for cost reduction and further quietness, and stably maintaining high support accuracy. A sliding bearing (4) includes an inner member (5) having a mounting surface (9) with respect to a rotary shaft (2), and an outer member (6) being arranged on a radially outer side of the inner member (5). A radial bearing gap is formed between an outer peripheral surface (5a1) of the inner member (5) and an inner peripheral surface (7a1) of the outer member (6), and a lubricating oil is interposed in the radial bearing gap. Further, between the inner member (5) and the outer member (6), sealing gaps (S, S) for maintaining an oil level of the lubricating oil on both axial sides of the radial bearing gap are formed. At least a part of the mounting surface (9) of the inner member (5) is made of a metal.

Abstract: There is provided a motor including: an upper housing; a lower housing coupled to the upper housing to provide an internal space; a shaft disposed within the internal space and coupled to a hydrodynamic bearing assembly; a rotor core coupled to the shaft and rotated together with the shaft; and a balancing unit coupled to the shaft to correct a rotational imbalance at the time of rotation of the shaft and the rotor core.

Abstract: A motor includes a stationary portion and a rotating portion. The rotating portion includes a sleeve portion. The sleeve portion includes a communicating hole. A dynamic pressure bearing is defined in a first gap between a shaft portion and the sleeve portion. An upper seal portion and a lower seal portion are arranged radially outward of the dynamic pressure bearing. The upper seal portion and the lower seal portion are arranged in communication with each other through the communicating hole. The communicating hole and a space extending from the upper seal portion to the lower seal portion through the first gap are filled with a lubricating oil. A fixing region where an outer tubular portion and a base portion are fixed to each other is arranged to overlap with the dynamic pressure bearing in a radial direction in plan view.

Abstract: A dynamic pressure bearing is defined in a first gap between a shaft portion and a sleeve portion. An upper seal portion extending upward and a lower seal portion extending downward are arranged radially outward of the dynamic pressure bearing. Each of the upper seal portion and the lower seal portion includes a surface including a lubricating oil located therein. The upper seal portion and the lower seal portion are arranged in communication with each other through a communicating hole defined in the sleeve portion. The communicating hole and a space ranging from the upper seal portion to the lower seal portion through the first gap are filled with the lubricating oil. The axial distance between the surfaces of the lubricating oil in the upper seal portion and the lower seal portion is arranged to be shorter than the axial distance between an upper end and a lower end of the dynamic pressure bearing.

Abstract: A spindle motor includes a stationary portion and a rotating portion. The stationary portion preferably includes a shaft portion, a lower plate portion, and an outer tubular portion. The rotating portion preferably includes an inner tubular portion and a flange portion including a communicating hole. An upper seal portion is arranged radially outward of a first gap, and a lower seal portion is arranged radially outward of a second gap. The upper and lower seal portions are arranged in communication with each other through the communicating hole. The communicating hole and a space extending from the upper seal portion to the lower seal portion through the first gap, the second gap, and a third gap are filled with a lubricating oil. The third gap includes a dynamic pressure generation portion arranged to produce a radially inward pressure acting on the lubricating oil.

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: 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: An example rotating device is a disk drive device that includes a base, a hub on which a recording disk is to be mounted and which rotates relative to the base, and a fluid dynamic bearing unit that allows the hub to rotate relative to the base. The fluid dynamic bearing unit includes a shaft that performs relative rotation and a cylindrical member that encircles the shaft, the cylindrical member includes a thrust dynamic pressure generating groove which is provided in one end face of the cylindrical member and which generates thrust dynamic pressure, and the thrust dynamic pressure generating groove includes a cut-and-machined face.

Abstract: A fluid bearing assembly well-suited for use as high performance, web handling roller includes a stationary inner component that extends coaxially within a rotatable outer component. The inner component includes a single conical member from which extends a narrow stem. The delivery of fluid into a nominal gap between the inner and outer components creates a tapered bearing, with the outer component capable of frictionless rotation relative to the inner component. A thrust plate is axially mounted onto the stem and is retained thereon by a threaded nut. By delivering fluid into a nominal gap between the thrust plate and the outer component, a thrust bearing is created which counterbalances the net axial force produced from the tapered bearing. Furthermore, precise adjustment of the tapered bearing air gap can be achieved through rotation of the threaded nut, thereby enabling certain performance characteristics of the fluid bearing assembly to be modified.

Abstract: There are provided a hydrodynamic bearing assembly and a spindle motor including the same, the hydrodynamic bearing assembly including a sleeve having a shaft inserted therein, a rotor coupled to an upper portion of the shaft in an axial direction to rotate together with the shaft, and a stopper plate including a horizontal portion coupled to an upper surface of the sleeve in the axial direction and a vertical portion extending downwardly in the axial direction from an outer surface of the horizontal portion to be fixed to an outer surface of the sleeve in an outer diameter direction, and preventing the shaft from floating at a time of rotation of the shaft.

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: A bearing apparatus includes a stationary shaft, an upper annular portion, a lower annular portion, and a sleeve. An outer circumferential surface of the upper annular portion includes a cylindrical surface and an inclined surface arranged above the cylindrical surface. The cylindrical surface has an axial length smaller than that of the inclined surface of the upper annular portion. One of an upper surface of the sleeve and a lower surface of the upper annular portion includes a pumping groove array defined therein. An upper surface of a lubricating oil is defined in an upper capillary seal portion, while a lower surface of the lubricating oil is defined in a lower capillary seal portion. The upper capillary seal portion has an opening angle larger than that of the lower capillary seal portion.

Abstract: The invention relates to 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. According to the invention, at least parts of the surface patterns extend from the first rim to the second rim of the bearing surface.

Abstract: There is provided a hydrodynamic bearing assembly including: a shaft; a sleeve disposed to be spaced apart from the shaft by a predetermined interval to form a bearing clearance therewith; and a thrust member installed on the shaft, wherein at least one of the shaft, the sleeve, and the thrust member is provided with a dynamic pressure groove for generating fluid dynamic pressure in a lubricating fluid provided in the bearing clearance, and one side of a portion of the dynamic pressure groove into which the lubricating fluid is introduced is provided with a pressure reduction preventing groove for suppressing a reduction in pressure generated at the time of introduction of the lubricating fluid.

Abstract: A bearing apparatus includes a first cup portion defining a portion of a stationary portion of a bearing apparatus includes a first circular plate portion and a first cylindrical portion projecting downward from an outer edge portion of the first circular plate portion. A rotating portion of the bearing apparatus includes an annular recessed portion arranged to accommodate at least a lower end portion of the first cylindrical portion. The stationary portion includes a second cup portion including a second circular plate portion arranged to extend radially outward from an outer circumferential surface of a stationary shaft below the first cup portion and a second cylindrical portion arranged to project upward from an outer edge portion of the second circular plate portion. One of the first and second cup portions is integral with the stationary shaft defining a single monolithic member, and the other is fixed to the stationary shaft.

Abstract: The rotating device includes a fixing body having a shaft and a shaft holder fixing the shaft, a rotating body having a shaft encircling member with a cylinder part encircling a shaft and a disk part, and a middle encircling member encircling the cylinder part and facing the disk part via a clearance in the direction of a rotational axis, a radial dynamic pressure generating groove disposed in either one of a surface of the cylinder part and a surface of the shaft facing with each other in the radial direction, a thrust dynamic pressure generating groove disposed in either one of a surface of the disk part and a surface of the shaft holder facing with each other in the rotational axis direction, and a lubricant continuously present from a first air-liquid interface to a second air-liquid interface between the rotating body and the fixing body.

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: A spindle motor includes a base part including a base member and a lower thrust member fixed to the base member; a shaft having a lower end portion fixed to the base part and including a sealing groove formed in an outer peripheral surface thereof to form a liquid-vapor interface; an upper thrust member fixed to an upper end portion of the shaft; a rotating member including a sleeve part between the upper and lower thrust members; and an upper case fixing the upper end portion of the shaft. The shaft includes a connection groove recessed downwardly from an upper surface thereof and a communication hole for connecting the connection groove to the sealing groove. At least one of the shaft and a lower surface of the upper case has a connection part for connecting the connection groove to a space between the upper case and the upper thrust member.

Abstract: There are provided a hydrodynamic bearing assembly and a spindle motor including the same. The hydrodynamic bearing assembly includes: a sleeve supporting a shaft and forming a bearing clearance between the sleeve and the shaft, the bearing clearance filled with a lubricating fluid; a housing partially enclosing an outer peripheral surface of the sleeve; a rotor hub coupled to the upper end portion of the shaft and including an extension wall part partially facing an upper end portion of the sleeve and partially extended to be disposed outwardly of the housing; a stopper provided on a lower end portion of the shaft to be protruded outwardly in a radial direction to be caught by a lower end portion of the sleeve; and a circulation hole provided between the sleeve and the housing to allow a lower portion of the sleeve to communicate with an upper end portion of the housing.

Abstract: Provided is a fluid dynamic bearing device in which an assembly of a bearing sleeve to a housing is facilitated and which has excellent moment rigidity. A fluid dynamic bearing device (1) includes radial bearing parts (R1 and R2) and thrust bearing parts (T1 and T2). Thrust bearing surfaces (C and D) are respectively provided to first and second step surfaces (2d and 2e) of a housing (2), and the thrust bearing parts (T1 and T2) are respectively formed between the thrust bearing surfaces (C and D) and end surfaces (6b and 7b) of seal members (6 and 7) provided while protruding to an outer diameter side of a shaft member (5).

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: There are provided a hydrodynamic bearing assembly and a motor including the same. The hydrodynamic bearing assembly includes: a shaft; and a sleeve having the shaft rotatably provided therein, having a bearing clearance formed between the shaft and the sleeve and filled with oil, and including a communication hole allowing the bearing clearance to be in communication with the outside, wherein the communication hole is sealed by a gas-liquid separating unit allowing gas to pass therethrough and blocking liquid.

Abstract: There is provided a spindle motor including: a shaft; a sleeve rotatably supporting the shaft and forming a bearing clearance therewith filled with a lubricating fluid; a cover member installed on a lower end portion of the sleeve; a rotor hub coupled to an upper end portion of the shaft and having an extension wall part extended downwardly in an axial direction, to be disposed outwardly of the sleeve in a radial direction; and a stopper member fixedly installed on the extension wall part, and forming, together with an outer peripheral surface of the sleeve, a space having a liquid-vapor interface formed therein, the sleeve including a circulation hole formed therein to connect upper and lower portions thereof, the circulation hole being connected to a space formed by the stopper member and the outer peripheral surface of the sleeve.

Abstract: There are provided a hydrodynamic bearing assembly and a motor including the same. The hydrodynamic bearing assembly includes: a sleeve having a shaft hole into which a shaft is rotatably inserted; and a hub fixed to an upper end of the shaft and extended in an outer radial direction, wherein an upper surface of the sleeve and a lower surface of the hub have an oil interface formed therebetween to seal oil.

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 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: 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: There are provided a hydrodynamic bearing assembly and a motor having the same, the hydrodynamic bearing assembly including a shaft rotating together with a rotor case; and a sleeve rotatably supporting the shaft, wherein at least one of the shaft and the sleeve has first and second dynamic pressure grooves formed therein, the first dynamic pressure groove being disposed in an upper portion of at least one of the shaft and the sleeve in an axial direction and having a herringbone shape and the second dynamic pressure groove being disposed in a lower portion of at least one of the shaft and the sleeve in the axial direction so as to be spaced apart from the first dynamic pressure groove and having a spiral shape.

Abstract: A rotating device includes: a rotating body, a fixed body and lubricant. A surrounding member in the fixed body has a sleeve and a housing for surrounding the sleeve. A first radial dynamic pressure generating groove and a second radial dynamic pressure generating groove are formed on at least one of the inner circumferential surface of the sleeve and the outer circumferential surface of a shaft in the rotating body. The sleeve has a flange portion protruding radially outward at the end portion of the sleeve near to a hub in the rotating body. A concave portion, which is made by axially concaving at least part of the area corresponding to a wall thickness of the sleeve on the inner circumference side of the flange portion, is circumferentially provided in the flange portion.

Abstract: The invention relates to a spindle motor having a fluid dynamic bearing system comprising axial and radial bearings that contains a rotor component (14) which encloses a stationary shaft (12), which in turn is connected at both its ends to axially aligned bearing parts (16; 18) that are fashioned such that they form capillary sealing gaps (32; 34), a recirculation channel (28) filled with bearing fluid that connects the remote regions of the bearing to each other, and an electromagnetic drive system (42, 44) for driving the rotor component.