| ALPHANA TECHNOLOGY CO., LTD. Patent applications |
| Patent application number | Title | Published |
| 20120120526 | Fluid Dynamic Bearing Unit and Disk Drive Device Including The Same - A first sleeve rotatably extends around a shaft. First and second flanges are fixed to the shaft. A second sleeve extending around the first sleeve is fixed thereto. A first annular member fixed to the second sleeve surrounds the first flange. A second annular member fixed to the second flange surrounds a portion of the second sleeve. A first capillary seal includes a clearance between the first flange and the first annular member. A second capillary seal includes a clearance between the second annular member and the second sleeve. Lubricant is provided in the clearances in the first and second capillary seals. The second annular member and the second sleeve are designed so that the lubricant in the clearance in the second capillary seal can be viewed from a point in a radial position which is outward of the second sleeve as seen in an axial direction. | 05-17-2012 |
| 20120093446 | ROTATING APPARATUS CAPABLE OF IMPROVING THE ROTATION RELIABILITY EVEN AFTER HAVING BEEN DOWNSIZED, AND METHOD FOR MANUFACTURING THE ROTATING APPARATUS - A disk drive device includes a base plate, a hub, and a bearing unit. The bearing unit includes an outer sleeve, an inner sleeve, a shaft, a radial dynamic pressure groove, and a lubricant agent. In the joined portion of the outer sleeve and the hub, there are formed a recessed portion, which is a binding region, where the outer sleeve and the hub are joined together with a hardening resin present between the outer sleeve and the hub and a tilt preventing portion, provided on both the sides of the recessed portion in the axial direction of the outer, which is a raised region that forms a portion narrower than a gap, between the outer sleeve and the hub, corresponding to the recessed portion. | 04-19-2012 |
| 20120090163 | ROTATING APPARATUS CAPABLE OF IMPROVING THE SHOCK RESISTANCE AND METHOD FOR MANUFACTURING THE ROTATING APPARATUS - A disk drive device includes a hub, a base plate, and a bearing unit. The bearing unit includes a shaft housing member, joined to the hub, having a through-hole in the center, a shaft having a smaller diameter section and a larger diameter section, a radial dynamic pressure grooves, and a lubricant agent. The opening shape of bearing hole of the base plate is so formed as to be larger than the outer shape of the larger diameter section. In the bearing unit, the larger diameter section of the bearing unit is fixed by a hardening resin present between the bearing unit and the bearing hole. | 04-19-2012 |
| 20120033324 | ROTATING BODY FOR FLUID DYNAMIC BEARING CAPABLE OF BEING THINNED AND BEING IMPROVED IN ROTATIONAL ACCURACY AND METHOD OF PRODUCING THE ROTATING BODY FOR FLUID DYNAMIC BEARING - A rotating body for a fluid dynamic bearing used for rotating a recording disk that has been mounted therein include: a rotating shaft portion in which a cylindrical portion that serves as a rotating shaft and a protruding portion extended radially outward from one end of the cylindrical portion are formed integrally with each other; and a hub that is to be connected to the end portion near to the outer circumference of the protruding portion and that has a mounting seat portion on which the recording disk is to be mounted. | 02-09-2012 |
| 20110309709 | ROTATING MACHINE PROVIDED WITH COIL AND METHOD OF PRODUCING THE ROTATING MACHINE - In a rotating machine, a recording disk is mounted on a hub. A base rotatably supports the hub through a bearing unit. A core is fixed to the base and includes an annular portion and a salient pole radially extending therefrom. A coil is formed by winding a wire around the salient pole. The wire is pulled out to the back surface of the base through a pull-out hole provided in the base and soldered to a wiring. | 12-22-2011 |
| 20110304238 | ROTATING MACHINE PROVIDED WITH STATOR CORE - A recording disk is to be mounted on a hub. A base rotatably supports the hub through a bearing. A stator core is fixed to the base and includes an annular portion and a salient pole extending radially therefrom. A magnet faces the salient pole radially and is rotated with the hub. The magnet has a plurality of magnetic poles in the circumferential direction such that each of the plurality of magnetic poles faces the salient pole. The salient pole includes a rod-shaped body around which a wire is wound and a tooth portion that is provided radially outside the rod-shaped body and extends circumferentially. The circumferential end located at the end in the circumferential direction of the tooth portion is located radially inside a circumscribed circle passing through the tip located at the radially outermost end of the tooth portion. | 12-15-2011 |
| 20110279925 | ROTATING DEVICE AND A METHOD FOR MANUFACTURING A ROTATING DEVICE - In a disk drive device, a magnetic recording disk is mounted on a hub. A base rotatably supports the hub via a bearing unit. The base has a ring-shaped wall that surrounds the bearing unit and that protrudes towards the hub. A laminated core is fixed to the base. The laminated core has a ring portion and twelve teeth that radially outwardly extend from the ring portion. Coils are wound around the twelve teeth. The base includes an increasing-thickness portion formed so that the less the distance between a part of the increasing-thickness portion and the ring-shaped wall is, the thicker the part of the increasing-thickness portion becomes. | 11-17-2011 |
| 20110255191 | DISK DRIVE DEVICE - A disk drive device includes a base member; a hub on which a recording disk is placed; a bearing unit arranged on the base member for rotatably supporting the hub; and a spindle drive unit for rotationally driving the hub, wherein the spindle drive unit includes a stator core having salient poles, a coil wound around each of the salient poles, and a magnet having a plurality of magnetic poles arranged in a circumferential direction opposed to the salient poles, the hub includes an outer cylindrical portion formed of a magnetic material and engaged with an inner periphery of the recording disk, and an inner cylindrical portion fixing an outer periphery of the magnet, the number of magnetic poles is an even number in a range of 10 to 16, and the number of salient poles is a multiple of 3 in a range of 12 to 24. | 10-20-2011 |
| 20110200279 | ROTARY DEVICE - A rotary device according to an aspect of the invention includes: a sleeve having an inner cylindrical surface, a first end portion and a second end portion at respective ends of the inner cylindrical surface; a shaft that is accommodated in the inner cylindrical surface in a manner rotatable relative to the inner cylindrical surface; a fluid present in a space between the shaft and the sleeve; a first pump portion formed in a middle portion of the inner cylindrical surface and configured to cause the fluid to flow toward the first end portion by the relative rotation of the shaft and the sleeve; a first radial narrow gap formed at a region of the inner cylindrical surface on a side of the first end portion with respect to the first pump portion; and a first circulation path communicated with the first pump portion. | 08-18-2011 |
| 20110199706 | PRODUCTION METHOD OF DISK DRIVE DEVICE FOR CLEANING SUBASSEMBLIES AND DISK DRIVE DEVICE PRODUCED BY SAID PRODUCTION METHOD - A production method of a disk drive device includes: an assembling process of assembling a subassembly by incorporating at least a bearing unit in a hub in a clean room; a pouring process of pouring a lubricant in the bearing unit; a cleaning-liquid discharging process of discharging a cleaning liquid to the hub; a cleaning-liquid intake process of taking in the cleaning liquid discharged to the hub; and a sealing process of sealing the subassembly in a seal-material. | 08-18-2011 |
| 20110181986 | DISK DRIVE DEVICE PROVIDED WITH LUBRICANT-FILLED FLUID DYNAMIC BEARING - 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. | 07-28-2011 |
| 20110176240 | DISK DRIVE DEVICE THAT ROTATES A DISK - A disk drive device comprises a hub on which a magnetic recording disk is to be mounted; a base rotatably supporting the hub through a bearing unit; a sintered core fixed to the base, the sintered core having a ring portion and nine teeth that extend radially from the ring portion; coils wound around nine teeth; and a cylindrical magnet fixed to the hub. The sintered core is formed by heat-treating an iron powder. At least one of (a) the surfaces of particles of the iron powder and (b) the surfaces of the sintered core is insulated. | 07-21-2011 |
| 20110154875 | PRODUCTION METHOD OF ROTATING DEVICE HAVING THRUST DYNAMIC PRESSURE GENERATING SITE ON WHICH A THRUST PRESSURE PATTERN IS FORMED AND ROTATING DEVICE PRODUCED BY SAID PRODUCTION METHOD - A thrust dynamic pressure pattern is marked on a rotating member or fixed member set on a rest table. A pressure for marking is applied to a member to be marked in a cycle of applying and releasing the pressure, and a supplemental force for keeping the member to be marked, still is separately applied. According to the present embodiment, a rotating device can be provided that narrows down a bearing gap and improves the efficiency of raking up a lubricant so as to increase the dynamic pressure by reducing the deformation of the shape of the protrusions of a thrust dynamic pressure pattern and the variation in the height of the protrusions when forming the thrust dynamic pressure pattern in a method of producing a rotating device. | 06-30-2011 |
| 20110116191 | DISK DRIVE DEVICE EQUIPPED WITH A BEARING UNIT RELATIVELY ROTATABLY SUPPORTING A HUB AGAINST BASE MEMBER - A disk drive device has a hub so configured as to place and hold recording disks. Where the non-rotating eigenfrequency of resonance in a secondary rocking mode with the recording disks placed on the hub is defined to be F0 (Hz) and the rotational frequency of the hub is defined to be N (Hz), an extending part of the hub and a second cylinder part of the hub are formed such that the radial dimension of the extending part is smaller than the axial dimension of the second external cylinder part to satisfy to a relation F0>N·(3·P+2). | 05-19-2011 |
| 20110116188 | DISK DRIVE DEVICE HAVING FUNCTION OF DISCHARGING STATIC ELECTRICITY - A bearing unit includes a shaft and a hub as a conductive rotating body that supports a recording disk. Also, the bearing unit includes a conductive resin housing configured to surround at least part of the shaft to support the shaft and to be able to conduct electricity to the recording disk via the shaft. The conductive resin housing includes a conductive adhesive to be applied to secure conduction with the base housing. The conductive resin housing has an exposed portion where the inner layer of the conductive resin housing is exposed, at a position to which the conductive adhesive is applied. | 05-19-2011 |
| 20110109995 | BEARING LUBRICANT, BEARING AND DISK DRIVE DEVICE - A bearing lubricant includes a base oil containing an ester compound consisting of 2-ethyl-2-methyl-1,3-propanediol and at least one of carboxylic acids having 5 to 12 carbon atoms, the ester compound being represented by the following formula (1), in which the base oil has a kinetic viscosity at approximately 40° C. of approximately 7 to 15 mPa, and has a pour point of approximately −60° C. or less: | 05-12-2011 |
| 20110109991 | DISK DRIVE DEVICE IN WHICH REDUCTION IN UNBALANCED AMOUNT CAN BE ADJUSTED - A disk drive device includes: a hub on which a recording disk is to be mounted; a base member; a bearing unit configured to support the hub in a manner in which the hub can be relatively rotated with respect to the base member; an extended annular groove portion provided in part of the hub around the rotational axis of the hub; and a weight member that is installed in the extended annular groove portion to adjust a rotational balance when the recording disk is being rotated with the hub. The weight member has a fixing mechanism that is slidable, when installed, in the direction of the extended annular groove portion and that can substantially maintain a stopped state at a fixing position. | 05-12-2011 |
| 20110096437 | DISK DRIVE DEVICE HAVING A LAMINATED CORE - In A disk drive device, a magnetic recording disk is to be mounted on a hub. A base plate rotatably supports the hub through a bearing unit. A projecting portion is formed on the upper surface of the base plate. The projecting portion has a cylindrical side surface, the center of which being along the rotational axis of the motor. A laminated core is formed by laminating eight magnetic steel sheets and has a ring portion and a plurality of teeth that extend radially from the ring portion. The disk drive device has a tubular vibration-deadening ring. The outer surface of the vibration-deadening ring is press-fitted into the ring portion, and the inner surface is fixed to the side surface of the projecting portion. The outer surface of the vibration-deadening ring is pressed against the ring portion at least at a position closer, in the direction along the rotational axis of the motor, to the upper surface of the laminated core than to the lower surface of the laminated core. | 04-28-2011 |
| 20110080673 | METHOD MANUFACTURING OF FLUID DYNAMIC BEARING USING CUTTING TOOL THAT PERFORMS MICRO ALTERNATING DRIVE, FLUID DYNAMIC BEARING MANUFACTURED BY USING THE METHOD, AND DISK DRIVE DEVICE USING THE BEARING - A method manufacturing of a fluid dynamic bearing includes: forming a substantially linear groove having a length corresponding to a circumferential direction width of the dynamic pressure groove formed on the inner circumferential surface of a shaft housing hole portion, along the circumferential direction of a surface orthogonal to a first processing direction along the central axis direction of a work, by a byte that performs a micro alternating drive in a second processing direction orthogonal to the first processing direction; and extending the dynamic pressure groove that extends in the first processing direction by continuously forming the substantially linear grooves in the first processing direction by displacing the relative positions of the work and the byte in the first processing direction. | 04-07-2011 |
| 20110064341 | DISK DRIVE DEVICE CAPABLE OF BEING IMPROVED IN ANTI-VIBRATION CHARACTERISTIC - A disk drive device includes: a hub on which a recording disk is to be mounted; a shaft; a sleeve configured to house the shaft and to be rotatable relatively with respect to the shaft; a radial space portion formed between the inner circumferential surface of the sleeve and the outer circumferential surface of the shaft; a radial dynamic pressure generating portion configured to generate radial dynamic pressure between at least part of the inner circumferential surface of the sleeve and the outer circumferential surface of the shaft in the radial space portion; and lubricant. The axial length of the radial dynamic pressure generating portion is formed to be longer than the diameter of the radial dynamic pressure generating portion such that radial dynamic pressure, which is defined with the axial length of the radial dynamic pressure generating portion and the diameter thereof being parameters, is greater than or equal to a predetermined minimum reference value. | 03-17-2011 |
| 20110063964 | METHOD OF MANUFACTURING A DISK DRIVE DEVICE HAVING BASE MEMBER, BEARING UNIT, DRIVE UNIT AND HUB, AND DISK DRIVE DEVICE MANUFACTURED BY THE MANUFACTURING METHOD - A method of manufacturing a disk drive device including: assembling a subassembly by fixing at least a bearing unit, a drive unit and a hub to a base member in a first clean room; cleaning the subassembly in a second clean room; and sealing the subassembly by a sealing member. The first clean room and the second clean room are communicated with each other by a communicating opening for transferring the subassembly, and an atmospheric pressure in the second clean room is equal to or higher than that in the first clean room. | 03-17-2011 |
| 20110051287 | DISK DRIVE DEVICE WITH IMPROVED SHOCK RESISTANCE - The disk drive device includes a base plate, a hub on which a recording disk is mounted, a shaft bearing unit that is arranged on the base plate and that rotatably supports the hub, and a spindle drive unit that drives the hub to rotate. The spindle driving unit includes a stator core having a salient pole, a coil wound around the salient pole, and a magnet opposed to the salient pole. The hub formed of a magnetic material includes an outer cylindrical portion engaged with an inner circumference of the recording disk. A shaft is inserted into a sleeve, and the sleeve, which is of an approximate cylindrical shape, is inserted into a housing as part of the shaft bearing unit. The shaft is fixed to the rotational center of the hub, rotating along the axis together with the hub. | 03-03-2011 |
| 20110043948 | DISK DRIVE DEVICE WITH HUB - The disk drive device includes a base member, a hub, a bearing unit which is arranged on the base member and which rotatably supports the hub, and a spindle drive unit which drives the hub to rotate. The spindle drive unit includes a stator core having a salient pole, a coil wound around the salient pole and a magnet opposed to the salient pole. The hub formed of magnetic material includes an outer cylinder portion engaged with an inner circumference of a recording disk and an inner cylinder portion to which an outer circumference of the magnet is fixed. The diameter of the inner cylinder portion is larger than the diameter of the outer cylinder portion. | 02-24-2011 |
| 20110033144 | DISK DRIVE DEVICE - In a disk drive device according to an embodiment, radial dynamic pressure corresponding portions are structured such that the diameters thereof expand toward the axial outside of the sleeve, and that the shaft is in surface-contact with each of the radial dynamic pressure corresponding portions when the rotational drive of the disk drive device is stopped. Further, a herringborn-shaped radial dynamic pressure groove is formed in each of the radial dynamic pressure corresponding portions. The radial dynamic pressure groove in each radial dynamic pressure corresponding portion is formed such that the axial outside length from the turned-back portion of the herringborn-shape is longer than the axial inside length therefrom. | 02-10-2011 |
| 20110033143 | DISK DRIVE DEVICE IMPROVED IN ANTI-VIBRATION CHARACTERISTIC - A disk drive device includes a rotating body, a fluid dynamic bearing unit that rotatably supports the rotating body, and a drive unit. The fluid dynamic bearing unit has: a lubricant holding portion in which lubricant is held; a first thrust dynamic pressure groove with which a first thrust dynamic pressure generating portion for generating the dynamic pressure in the pump-in direction, which is oriented toward the inside of the lubricant holding portion, is structured; and a second thrust dynamic pressure groove with which a second thrust dynamic pressure generating portion for generating at least the dynamic pressure in the pump-out direction, is structured. The first thrust dynamic pressure generating portion and the second thrust dynamic pressure generating portion have dynamic pressure generation characteristics in which, when the rotating body is biased in the rotational axis direction from the state where the rotating body is floating in the lubricant, the sum of the changes in the dynamic pressure in the pump-out direction is larger than that of the changes in the dynamic pressure in the pump-in direction. | 02-10-2011 |
| 20110007989 | DISK DRIVE DEVICE PROVIDED WITH FLUID DYNAMIC BEARING UNIT - 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 D | 01-13-2011 |
| 20110002212 | ADHESION STRUCTURE AND METHOD USING ELECTRICALLY CONDUCTIVE ADHESIVE, DISK DRIVE DEVICE USING THE ADHESION STRUCTURE AND METHOD, AND METHOD FOR MANUFACTURING THE DISK DRIVE DEVICE - A base plate containing aluminum as a main component and an electrically conductive counter plate are bonded together through the medium of an electrically conductive adhesive. Even when an oxide film is formed on the surface of the base plate, electrical continuity between the base plate and the counter plate, which are connected together through the medium of the electrically conductive adhesive, is improved by a process of applying a resistance lowering voltage, which reduces the resistance component due to the oxide film by causing a dielectric breakdown. | 01-06-2011 |
| 20100328819 | DISK DRIVE DEVICE FOR ROTATING A DISK - In a disk drive device, a recording disk is mounted on a rotor. A base has a bearing hole, the center of which is along the rotational axis of the rotor. A bearing unit rotatably supports the rotor with respect to the base, the bearing unit being glued to the bearing hole. A ring-shaped first groove, the center of which is along the rotational axis, is arranged on a side surface of the bearing hole. A ring-shaped second groove, the center of which is along the rotational axis, is arranged on an outer surface of the housing, the outer surface contacting the side surface of the bearing hole. The position of the second groove with respect to its direction along the rotational axis is different from the position of the first groove with respect to its direction along the rotational axis. The base and the bearing unit are electrically connected by a conductive resin applied along an edge portion of the bearing hole, the edge portion being on a lower surface of the base. | 12-30-2010 |
| 20100302673 | DISK DRIVE DEVICE IMPROVED IN STIFFNESS OF FLUID DYNAMIC BEARING - A disk drive device includes a bearing unit and a drive unit. The bearing unit includes: a shaft; a sleeve configured to allow relative rotation, with the shaft as the axis; a flange projected in the radial direction of the shaft and configured to rotate integrally with the shaft; a flange housing space portion provided continuously from the sleeve and configured to rotatably house the flange; a counter plate structured with both a first surface, which faces the end surface in the axial direction of the flange and seals the flange housing space portion, and a second surface that is opposite to the first surface. The projected dimension of the flange is designed to be larger than the wall thickness of the flange surrounding wall portion in the radial direction of the flange, the flange surrounding wall portion defining the flange housing space portion. | 12-02-2010 |
| 20100277833 | Fluid dynamic bearing unit and disk drive device including the same - A first sleeve rotatably extends around a shaft. First and second flanges are fixed to the shaft. A second sleeve extending around the first sleeve is fixed thereto. A first annular member fixed to the second sleeve surrounds the first flange. A second annular member fixed to the second flange surrounds a portion of the second sleeve. A first capillary seal includes a clearance between the first flange and the first annular member. A second capillary seal includes a clearance between the second annular member and the second sleeve. Lubricant is provided in the clearances in the first and second capillary seals. The second annular member and the second sleeve are designed so that the lubricant in the clearance in the second capillary seal can be viewed from a point in a radial position which is outward of the second sleeve as seen in an axial direction. | 11-04-2010 |
| 20100254639 | FLUID DYNAMIC BEARING FILLED WITH LUBRICANT IN WORK AREA HAVING REDUCED PRESSURE, METHOD OF MANUFACTURING THE FLUID DYNAMIC BEARING, APPARATUS FOR MANUFACTURING THE FLUID DYNAMIC BEARING, AND ROTATING DEVICE - In an apparatus for manufacturing a fluid dynamic bearing, a housing portion defines a first work area. A vacuum pump discharges air in the first work area. A lubricant discharge device is arranged in the first work area, and discharges a lubricant into an inlet of a reservoir for storing the lubricant of the fluid dynamic bearing. At least one aperture is provided in the housing portion. A first door closes the aperture and a second door closes the aperture. Between the first door and the second door, when both have closed the aperture, a second work area is formed where the fluid dynamic bearing is placed. | 10-07-2010 |
| 20100254044 | DISK DRIVE DEVICE HAVING FLUID DYNAMIC BEARING WITH POROUS MEMBER AT POSITION IN WHICH LUBRICANT IS CHARGED - The present invention provides a disk drive device that can easily be reduced in size with a simple structure by reducing foreign matters floating in a lubricant to reduce inconvenience caused by the floating foreign matters. The disk drive device includes a fixed body section, a rotating body section, a bearing unit and a drive unit. The bearing unit includes a shaft that is a rotation center, a sleeve that has an accommodating portion in which the shaft is accommodated and that permits relative rotation around the shaft, a radial space defined by an inner wall surface of the sleeve-accommodating portion and an outer wall surface of the shaft, first and second radial dynamic pressure grooves that generate a radial dynamic pressure in at least one of the inner wall surface of the sleeve and the outer wall surface of the shaft that define the radial space, a lubricant charged into the radial space, and a porous filter that is disposed in at least a portion of the charging space in which the lubricant is charged, thereby capturing a foreign matter contained in the lubricant. | 10-07-2010 |
| 20100254043 | METHOD OF MANUFACTURING DISK DRIVE DEVICE FOR REDUCING ADHESIVE AMOUNT OF PARTICLES, AND DISK DRIVE DEVICE MANUFACTURED BY THE METHOD - In a method of manufacturing a disk drive device, a cleaning process and an assembly process are performed in succession in a clean room having a predetermined cleanness level. The cleaning process includes an alkali cleaning process, a first purified water cleaning process, a second purified water cleaning process, a spray cleaning process, a draining process and a drying process. In the first purified water cleaning process, purified water ultrasonic wave cleaning is sequentially performed on the base member of the disk drive device to be cleaned by using ultrasonic waves of frequencies of 40 kHz, 68 kHz and 132 kHz in purified water filled in a first purified water cleaning tank. The cleaned base member and other components having a predetermined cleanness level are assembled in the assembly process continuous from the cleaning process. | 10-07-2010 |
| 20100247008 | FLUID DYNAMIC BEARING, METHOD OF MANUFACTURING FLUID DYNAMIC BEARING, ROTATING DEVICE, AND DISK DRIVE DEVICE - 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. | 09-30-2010 |
| 20100239194 | DISK DRIVE DEVICE IMPROVED IN HANDLING PROPERTY - A disk drive device includes a base member, a hub member, a shaft, a flange, a sleeve, a thrust dynamic pressure generation portion including thrust dynamic pressure grooves such that thrust dynamic pressure is generated in a thrust space, a radial dynamic pressure generation portion including radial dynamic pressure grooves such that radial dynamic pressure is generated in a radial space, a lubricant filled in the thrust space in the thrust dynamic pressure generation portion and the radial space in the radial dynamic pressure generation portion, a capillary seal portion for holding the lubricant in the thrust space and the radial space, and a circulation pathway by which the thrust dynamic pressure generation portion and the radial dynamic pressure generation portion communicate with each other in order to circulate the lubricant. At least one of the areas among where the thrust dynamic pressure groove is formed and where the radial dynamic pressure groove is formed is made of an impact absorption body with a coefficient of elasticity less than or equal to 20 GPa. | 09-23-2010 |
| 20100238591 | DISK DRIVE DEVICE ROTATIONALLY DRIVING RECORDING DISK - A disk drive device includes: a hub on which a recording disk is to be mounted; a base configured to rotatably support the hub via a bearing; a core that is fixed to the base and includes a circular portion and S salient poles (where S is a natural number greater than or equal to 3) extending from the circular portion in the diameter direction; a three-phase coil that is formed by being wound around each of the S salient poles; and a magnet that is fixed to the hub and faces the S salient poles in the diameter direction, and that is provided with P driving magnetic poles in the circumferential direction (where P is a natural number greater than or equal to 2). In the disk drive device, the fundamental frequency component of the cogging torque based on the LCM (Least Common Multiple) of S and P (where S is the number of the salient poles of the core and P is the number of the driving magnetic poles of the magnet), is smaller than the second frequency component of the cogging torque, the frequency of which is twice the fundamental frequency. | 09-23-2010 |
| 20100238590 | DISK DRIVE DEVICE ROTATIONALLY DRIVING RECORDING DISK - A disk drive device is provided with a base, a hub on which a recording disk is to be mounted, a bearing unit arranged on the base and configured to rotatably support the hub, and a spindle drive unit configured to rotatably drive the hub. A circumferential ring wall portion is arranged on the outer circumference of the base and formed of a plastic. | 09-23-2010 |
| 20100231068 | DISK DRIVE DEVICE FOR ROTATING A DISK - In the brushless motor, a magnetic recording disk is to be mounted on a hub. A base plate rotatably supports the hub on the upper surface. A laminated core is fixed on the upper surface of the base plate and has a ring portion and a plurality of teeth that extend radially from the ring portion. Coils are wound around the plurality of teeth. A cylindrical magnet is fixed to the hub and is magnetized for driving with a plurality of poles along the circumferential direction and is arranged to radially face the plurality of teeth of the laminated core. A wire of one end of one of the coils is drawn out to the bottom surface of the base plate through a hole arranged on the base plate. The wire is connected to a driving line for supplying a current to the coils at a position other than the position of the hole on the base plate. The hole of the base plate is plugged with a resin. | 09-16-2010 |
| 20100226046 | DISK DRIVE DEVICE FOR ROTATING A DISK - In the brushless motor, a hub has a cylindrical separating wall in between a yoke and two magnetic recording disks. The yoke is affixed to the inner surface of the separating wall of the hub using both a press-fit and adhesion. A first convex portion and a second convex portion are formed on the inner surface of the separating wall, and the yoke is pressed against these convex portions in the case where the yoke is press-fit. The first convex portion and the second convex portion are formed in a ring shape around the rotational axis of the motor. The diameter of the first convex portion is less than the diameter of the second convex portion. | 09-09-2010 |
| 20100220412 | MANUFACTURING METHOD OF DISK DRIVE DEVICE CAPABLE OF REDUCING AMOUNT OF UNBALANCE, DISK DRIVE DEVICE AND SUBASSEMBLY THEREOF - A disk drive device is provided with a recording disk, a base member, a bearing unit, and a hub member. In a marking step, unbalance information indicating the displacement of the center of gravity of the hub member with respect to the rotation center of the hub member is acquired, and an information mark containing the unbalance information is applied to at least the hub member or the base member. In an installing and adjustment step, the unbalance information is read form the information mark, and the position for installing the recording disk in an outer cylinder part is determined in accordance with the unbalance information so as to install the recording disk on the hub member. | 09-02-2010 |
| 20100202084 | DISK DRIVE DEVICE - In a brushless motor, the rotational frequency N (Hz) of the hub satisfies N| 08-12-2010 | |
| 20100195248 | DISK DRIVE DEVICE PROVIDED WITH FLUID DYNAMIC BEARING - 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. | 08-05-2010 |
| 20100192378 | METHOD FOR MANUFACTURING A FLUID DYNAMIC BEARING, A FLUID DYNAMIC BEARING, A MOTOR, AND A DISK DRIVE DEVICE - 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. | 08-05-2010 |
| 20100146772 | Motor adopting improved mechanism - A motor adopting an improved mechanism is composed of a stator having a shaft and a rotor provided with a sleeve and a hub, wherein the shaft is inserted into the hub and the hub is fixed on an outer circumferential surface of the sleeve. The outer circumferential surface of the sleeve is provided with a first outer circumferential surface, a second outer circumferential surface and a receiving surface that links between the first and second outer circumferential surfaces. The hub is provided with a base section, a through hole and a first protruded section protruding downward from the base section. A tip end portion of the first protruded section is provided with a hitting surface that contacts with the receiving surface of the sleeve and a second protruded section that links to the contacting surface and protrudes downward from the contacting surface. | 06-17-2010 |
| 20090316299 | DISK DRIVE DEVICE HAVING AIRTIGHT STRUCTURE WITH IMPROVED AIRTIGHTNESS - A disk drive device is configured such that a wall of a base plate is provided with a through hole that guides a lead from a drive unit outside. The through hole is covered by a sealing sheet having an insertion hole. The lead is guided from inside the housing via the insertion hole of the sealing sheet. The sealing sheet carries a curable resin. The curable resin, temporarily softened during a curing process, flows into a space between the base plate and the through hole and a space between the insertion hole and the lead. The curable resin is cured in this state, ensuring the airtightness of the housing. | 12-24-2009 |
| 20090236927 | BRUSHLESS MOTOR INCLUDING STATOR CORE AND DISK DRIVE - A brushless motor is provided. A stator core has a plurality of teeth extending radially from an annular portion of the stator core. The number of the teeth is an integral multiple of the number of coil-drive phases. Coil relief holes for allowing coils to enter are formed on the motor base. The number of the coil relief holes is less than the number of the teeth by the number of the coil-drive phases multiplied by N (N is a natural number). The number of turns of the motor-drive coil wound around one of the teeth corresponding to a portion of the motor base where the coil relief hole is not formed is set to less than that corresponding to a portion of the motor base where the coil relief hole is formed. | 09-24-2009 |
| 20090001844 | Motor adopting improved mechanism - A motor adopting an improved mechanism is composed of a stator having a shaft and a rotor provided with a sleeve and a hub, wherein the shaft is inserted into the hub and the hub is fixed on an outer circumferential surface of the sleeve. The outer circumferential surface of the sleeve is provided with a first outer circumferential surface, a second outer circumferential surface and a receiving surface that links between the first and second outer circumferential surfaces. The hub is provided with a base section, a through hole and a first protruded section protruding downward from the base section. A tip end portion of the first protruded section is provided with a hitting surface that contacts with the receiving surface of the sleeve and a second protruded section that links to the contacting surface and protrudes downward from the contacting surface. | 01-01-2009 |
| 20080290246 | Bearing device and motor mounted with the bearing device - A bearing device is composed of a shaft, a sleeve for supporting the shaft so as to be rotatable freely and a housing having a through hole into which the sleeve is inserted. A circumferential groove that extends in a circumferential direction is formed on either one surface of an outer circumferential surface of the sleeve and an inner circumferential surface of the housing. An axial groove that extends approximately in parallel to a central axis of the sleeve is formed on either one surface of the outer circumferential surface of the sleeve and the inner circumferential surface of the housing. The outer circumferential surface of the sleeve is glued to the inner circumferential surface of the housing by adhesive that intervenes in both the circumferential groove and the axial groove. | 11-27-2008 |