Abstract: The present invention provides a magnetic recording medium and a magnetic disk drive using the same, capable of keeping flying height and posture of the head slider constant when a discrete track medium (magnetic recording medium) includes tracks as data zones, and non-data zones (groove) formed between adjacent tracks.

Abstract: In a fluid dynamic bearing apparatus, an oil buffer is defined between a thrust gap and a pumping gap. The oil buffer has an axial dimension greater than that of the thrust gap, and/or has a radial dimension greater than that of the pumping gap. An air bubble generated in the thrust gap due to cavitation, for example, when a fluid dynamic bearing apparatus experiences a vibration can be dissolved in lubricating oil provided within the oil buffer. This prevents leakage of the lubricating oil due to the air bubble residing in the fluid dynamic bearing apparatus.

Abstract: Inner circumferential surfaces of a rotor holder and a turntable are in contact with an outer circumferential surface of a shaft. This stabilizes coaxiality of both the rotor holder and the turntable with respect to the shaft. An upper cover portion of the rotor holder includes fixing holes. The turntable includes fixing projections arranged to extend through the fixing holes to be in contact with a lower surface of the upper cover portion. A base end portion of each fixing projection is arranged at a level higher than that of an upper end portion of a corresponding one of the fixing holes. Therefore, even if dimensional errors of the rotor holder and the turntable cause a radial displacement between any fixing projection and a corresponding one of the fixing holes, the rotor holder and the turntable can be fixed to each other while maintaining coaxiality therebetween.

Abstract: A spindle motor for use in a 2.5 inch 7 mm high disk drive apparatus includes a base portion; a stator arranged above the base portion; a rotor hub including a cover portion positioned above the stator, and a side wall portion arranged to extend downward from an outer edge of the cover portion; a rotor magnet positioned radially outward of the stator, and fixed to an inner circumferential surface of the side wall portion of the rotor hub; and a bearing mechanism arranged to support the rotor hub and the rotor magnet such that the rotor hub and the rotor magnet are rotatable with respect to the base portion and the stator. A height of the rotor magnet as measured in an axial direction is preferably in a range of about 2 mm to about 3 mm (both inclusive), and a height of a stator core of the stator as measured in the axial direction is preferably in a range of about 50% to about 75% (both inclusive) of the height of the rotor magnet.

Abstract: There are provided an apparatus for clamping a disk and a motor assembly having the same. The apparatus for clamping a disk according to the present invention includes an apparatus for clamping a disk, including: a rotor case jointed with an outer peripheral surface of a shaft and rotating together with the shaft; a flange part including a disk mounting surface formed at a radial outer side of the rotor case and formed to be inclined as the disk mounting surface is toward the radial outer side; and a clamping member pressing and clamping the disk to the rotor case, wherein an inclination of the disk mounting surface of the flange part is changed depending on the position of the pressing point to the disk of the clamping member.

Abstract: There are provided a hydrodynamic bearing assembly capable of implementing a flat-type oil cover, while reducing a thickness of the oil cover, by strengthening the rigidity of the oil cover, a motor having the hydrodynamic bearing assembly, and a recording disk driving device equipped with the motor. The hydrodynamic bearing assembly includes: a sleeve having a shaft hollow provided at one side thereof, the shat hollow being inserted with a shaft; and an oil cover fixed to the sleeve in another direction of the shaft hollow and preventing a leakage of oil remaining in the shaft hollow, wherein a groove for securing rigidity is formed on at least one surface of the oil cover.

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, an upper thrust portion, and an outer tubular portion. The rotating portion preferably includes an inner tubular portion, a flange portion, an upper hub annular portion, and a lower hub annular portion. The flange portion includes a communicating hole. An upper surface of a lubricating oil is located in a fifth gap defined between an upper thrust portion and an upper hub annular portion, while a lower surface of the lubricating oil is located in a sixth gap defined between an outer tubular portion and a lower hub annular portion. The communicating hole and a space extending from the fifth gap to the sixth gap through a fourth gap, a first gap, a second gap, and a third gap are continuously filled with the lubricating oil.

Abstract: In a motor, a stationary portion includes a shaft portion and an upper thrust portion arranged to define a single continuous monolithic member together with the shaft portion, and arranged to extend radially outward from an upper portion of the shaft portion. The shaft portion includes a female screw portion recessed axially downward from an upper end thereof. An upper end of the single continuous monolithic member defined by the shaft portion and the upper thrust portion includes an upper end annular surface arranged to extend radially outward from the female screw portion perpendicularly or substantially perpendicularly to the central axis. An outside diameter of the upper end annular surface is greater than a diameter of an outer circumferential surface of the shaft portion.

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: According to one embodiment, a head gimbal assembly includes a load beam, a metal plate mounted on the load beam and constituting a gimbal includes a limiter portion, a flexure includes a plurality of conductors formed over the metal plate with an insulating layer therebetween, a slider includes a head and mounted on the gimbal, and a positioning reference mark formed on the limiter portion by parts of the conductors and configured to position the slider. The plurality of conductors includes conductors which conduct to the positioning reference mark through the metal plate and constitute an interleaved structure.

Abstract: There are provided a base structure for a device such as a hard disk drive and a hard disk drive having the same. The base structure includes: a base body including components mounted thereon and made of a non-aluminum material; and a base reinforcing part attached to the base body as an additional piece. More specifically, the base body is provided by press-molding a steel sheet and the base reinforcing part is provided by press-molding a steel sheet or is provided as a reinforcing plate separately attached to an outer surface of the base body, and the base structure further includes a reinforcing part processing member additionally provided in the reinforcing plate. The base structure for a device such as a hard disk drive and the like, in which the rigidity thereof is secured or the weight thereof is reduced by using various base reinforcing parts and reinforcing part processing members while the manufacturing costs of the base structure are reduced.

Abstract: Disclosed is a suspension assembly for a disk drive that includes: a mounting plate having a top-side and a bottom-side; a microactuator mounting structure formed in the mounting plate; a microactuator mounted in the microactuator mounting structure in which the microactuator has a top-side and a bottom-side; and a flexure attached to the bottom-side of the of mounting plate and the microactuator. The flexure includes a pad layer and a through-hole, in which the through-hole extends through the pad layer. An epoxy on the pad layer bonds widely to the microactuator and extends through the through-hole.

Abstract: Disclosed are a motor and a recording disc drive apparatus that can prevent a fluid in a fluid dynamic bearing from being discharged to the outside. A motor according to an aspect of the invention may include: a shaft; a sleeve having a cylindrical shape and supporting the shaft such that the shaft is rotatable therein; a rotor case engaged with an upper end of the shaft and having a rotor main wall having a cylindrical shape and protruding from one surface thereof in order to receive part of the sleeve; and a cover engaged with an end portion of the rotor main wall and extending the rotor main wall, wherein at least two sealing portions preventing leaks of a fluid used to lubricate the sleeve are formed between an internal circumferential surface, defined by the rotor main wall and the cover, and an outer circumferential surface of the sleeve.

Abstract: A rolling bearing provided with a shield plate which hardly induces the irregular deformation of an outer ring without increasing a cost is provided. A rolling bearing includes an inner ring and an outer ring; a plurality of rolling bodies which are held between the inner ring and the outer ring in a rotatable manner; and an annular shield plate which is engageable with an engaging groove portion which is formed on an inner peripheral surface of the outer ring along the circumferential direction and opens toward an inner peripheral surface side and an open end side. The shield plate includes: an annular shield body; and a plurality of engaging projections which are arranged along the outer peripheral portion of the shield body, project outwardly in the radial direction from the outer peripheral portion in an inclined state, and are engageable with the engaging groove portion.

Abstract: A fluid dynamic bearing mechanism includes a stationary shaft, a sleeve portion arranged to rotate with respect to the shaft, and a thrust portion including an upper end surface arranged oppose to a lower end surface of the sleeve portion. An inside surface of the thrust portion includes an inside surface contact portion arranged in contact with an outside surface of the shaft, and an inside surface lower non-contact portion spaced away from the outside surface of the shaft, and arranged to extend downward from a lower end of the inside surface contact portion. An outside surface of the thrust portion includes an outside surface inclined portion arranged in contact with an interface of a lubricating oil. The lower end of the inside surface contact portion is arranged at a level axially higher than that of a lower end of the outside surface inclined portion.

Abstract: 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.

Abstract: 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.

Abstract: A spindle motor includes a base portion, a rotor hub, a stator, and a circuit board. The base portion preferably includes a through hole and is arranged to spread out radially around a central axis. The rotor hub is arranged above the base portion to rotate about the central axis. The stator is arranged above the base portion, and includes coils each including at least one lead wire. The circuit board is arranged radially outward of the through hole, and arranged on a lower surface of the base portion. The base portion includes a communicating groove arranged to join the through hole and the circuit board to each other. The at least one lead wire of the coils is arranged to pass inside the through hole and the communicating groove to be electrically connected to the circuit board. The through hole is sealed with a sealant.

Abstract: According to one embodiment, a magnetic head includes a main pole configured to apply a perpendicular recording magnetic field to a recording layer of a recording medium, a return pole opposed to the trailing side of the main pole with a write gap therebetween and configured to reflux magnetic flux from the main pole to form a magnetic circuit in conjunction with the main pole, a coil configured to excite magnetic flux in the magnetic circuit includes the main pole and the return pole, a plurality of high-frequency oscillatory elements individually interposed between the main pole and the return pole, includes a plurality of magnetic films different in magnetic resonance frequency, and configured to individually apply high-frequency magnetic fields to the recording medium, and an electrical circuit configured to energize the high-frequency oscillatory elements.

Abstract: A spindle motor includes a rotary unit, a bearing mechanism, a stator, a base member, and a connector connected to a leader line extending from the stator through a communication hole of the base member. The connector includes a pedestal and a metal pin. The leader line is connected to a first pin terminal of the metal pin on a hole-positioning lower surface of a hole-defining portion of the pedestal. An upper surface of the metal pin is separated from the pedestal at a specified separation position between the first pin terminal and a second pin terminal. A connection position of the first pin terminal and the leader line on the hole-positioning lower surface is covered with an adhesive agent. The periphery of a gap between the metal pin and the pedestal over an extent from the first pin terminal to the separation position is sealed by the adhesive agent.

Abstract: According to one embodiment, a disk drive includes a carriage supporting a head configured to perform information processing for the recording medium, and a latch mechanism configured to latch and hold the carriage in a retracted position when an external force acts on the disk drive with the carriage being in the retracted position. The latch mechanism includes a latch member pivotable around an central axis between a latchable range and a released position. The latch member is configured to pivot in a latching direction within the latchable range before the engaging portion of the carriage starts to move when a rotational impact externally acts in a direction to pivot the carriage toward the information processing position with the carriage and the latch member being located in the retracted position and the latchable range, respectively.

Abstract: A stationary portion of a spindle motor includes a base member and a magnetic member. The magnetic member is arranged below a magnet and fixed to the base member. The magnetic member includes an annular plate portion arranged on an upper surface of the base member, and a projecting portion arranged to extend from the plate portion in an axial direction. At least a portion of the projecting portion is press fitted to a wall surface of the base member.

Abstract: A stator portion of a spindle motor includes a substantially cup-shaped base member including a bottom portion expanding in a radial direction, and a wall portion extending upwards from an outer edge portion of the bottom portion. A circuit board is fixed to a lower surface of the base member in a position on the outer side in the radial direction and on the upper side than the bottom portion. Accordingly, the thickness of the spindle motor in the axial direction can be reduced. The base member has a through hole formed axially through the bottom portion. An opening edge portion of the base member is covered with the insulating layer. A conducting wire from a coil is drawn through the through hole, led out along the surface of the insulating layer, and connected to the circuit board positioned on the outer side in the radial direction than the bottom portion.

Abstract: A hub includes first and second side surfaces respectively opposed to inner and outer circumferential surfaces of an upper portion of a magnetic member, and a ceiling surface arranged to interconnect an upper ends of the first and second side surfaces. The adhesive agent is interposed between the inner circumferential surface of the upper portion of the magnetic member and the first side surface of the hub and between the upper surface of the magnetic member and the ceiling surface of the hub. Radial distance between the inner circumferential surface of the upper portion of the magnetic member and the first side surface of the hub and axial distance between the upper surface of the magnetic member and the ceiling surface of the hub are smaller than radial distance between the outer circumferential surface of the upper portion of the magnetic member and the second side surface of the hub.

Abstract: 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.

Abstract: 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.

Abstract: A tray control method for a disk drive including a tray for carrying a disk, a detect switch movable to different inclined positions for detecting different positions of the tray during tray ejection and retraction operation, a firmware for receiving signals transmitted by the detect switch upon reaching the different inclined positions so as to adjust a voltage applied to a DC motor and the speed for moving the tray to the different positions such that the tray moves stably when retracting into and ejecting from the disk drive.

Abstract: A tray control method for a disk drive including a tray for carrying a disk, a detect switch movable to different inclined positions for detecting different positions of the tray during tray ejection and retraction operation, a firmware for receiving signals transmitted by the detect switch upon reaching the different inclined positions so as to adjust a voltage applied to a DC motor and the speed for moving the tray to the different positions such that the tray moves stably when retracting into and ejecting from the disk drive.

Abstract: A tray control method for a disk drive including a tray for carrying a disk, a detect switch movable to different inclined positions for detecting different positions of the tray during tray ejection and retraction operation, a firmware for receiving signals transmitted by the detect switch upon reaching the different inclined positions so as to adjust a voltage applied to a DC motor and the speed for moving the tray to the different positions such that the tray moves stably when retracting into and ejecting from the disk drive.

Abstract: The invention provides a jam-proof device of a slot-in optical disk drive. In the jam-proof device, a contact pin protrudes from one end of the loading bar, the other end of the loading bar is pivoted with a pivot on a first side of the casing, and a block protrudes adjacent to the pivot. One end of the unloading bar is pivoted on a second side of the casing opposite to the first side, and a reception end is formed at the other end of the unloading bar to extend to a center of the casing. A distance between the block and the reception end at a default position is shorter than a diameter of an 8-cm disc to prevent the disc from entering the slot-in optical disk drive.

Abstract: According to one embodiment, a storage device includes a clamp ring on a disc, configured to fix the disc to a spindle motor configured to rotate the disc, and a screw configured to fix the clamp ring to the spindle motor, and includes a screw-head and a recess in the screw-head, a center of the recess being decentered from a center of the screw-head.

Abstract: 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.

Abstract: A disc drive (1) comprises first clamping means (5) and second clamping means (7) for supporting an optical disc (3) that is to be played in the disc drive (1). Drive means (9) is provided for rotating the optical disc (3) relative to optical means (11) for writing data to, or reading data from, the optical disc (3). The disc drive (1) further comprises a data storage medium (13) for storing data such as embedded software for controlling the operation of the disc drive (1). The data storage medium (13) is permanently located in the disc drive (1), thereby being permanently available for controlling the operation of the disc drive (1). The data storage medium (13) is located coaxially with optical disc (3) that is to be inserted into the disc drive (1) for playback. The data storage medium (13) is also positioned such that, during playback of a normal optical disc (3), the data storage medium is located on the reverse side of the optical disc (13), i.e. the non-optical side of the optical disc (3).

Abstract: In a brushless motor, the rotational frequency N (Hz) of the hub satisfies N<F0/(3*P+2), where F0 (Hz) is an Eigen frequency of the second order rocking-mode resonance when not rotating in the situation where the recording disk is mounted on the hub. The recording disk is mounted on the hub. A base plate rotatably supports the hub. A laminated core is fixed to the base. The core has a ring portion and a plurality of teeth that extend radially from the ring portion. Coils are wound around the plurality of teeth. The coils are three-phase driven. A cylindrical magnet is fixed to the hub. The cylindrical magnet are magnetized for driving with P (P is a natural number) poles along the circumferential direction and are arranged to radially face the plurality of teeth.

Abstract: Method and apparatus for providing a storage medium with variable track widths. In accordance with various embodiments, a data storage medium is rotated by a motor. A write transducer is used to write concentric data tracks to the storage medium during said rotation. The tracks are provided with variable track widths established by selectively changing a rotational velocity of the medium. The variable track widths can be gradual and/or abrupt, depending on the requirements of a given application. Gradual variations in track width can be used by a linear actuator with a linear translation path to emulate tracks written along a pivot translation path of a rotary actuator. Abrupt variations in track width can be used to provide different zones of tracks having different specified track widths. The tracks may be written using an electron beam recorder (EBR) with a constant write beam power level.

Abstract: A disc can be supported stably and surely.

Abstract: In a hydrodynamic bearing device in which a radial bearing face having a dynamic pressure generating groove on a shaft or an inner periphery of a sleeve is provided and a clearance between the shaft and the sleeve is filled with lubricant, an annular depression is provided on one end face of the sleeve adjacent to a rotor hub and a cover plate for covering the depression is attached to the sleeve so as to define a reservoir for the lubricant or air for the purpose of preventing such a risk that absence of an oil film occurs in clearances of a bearing of the hydrodynamic bearing device due to outflow of oil upon forcing of the oil by air received into the bearing. A step portion is provided on the other end face of the sleeve such that the step portion and the reservoir are communicated with each other by a communication hole. During operation of the hydrodynamic bearing device, air in the hydrodynamic bearing device reaches the reservoir via the communication hole so as to be discharged from the reservoir.

Abstract: A component for restricting relative movement of a rotor and a shaft is disclosed. A motor may include a shaft and a rotor, where the rotor is disposed for relative rotation with respect to said shaft. A component is operable to restrict relative movement of the rotor and the shaft, where the component includes a first surface operable to receive a fluid.

Abstract: A disc drive apparatus comprises: a spindle motor 20 for hold a disc 2 and for rotate it; an optical head 7 for conducting either one of recording or reproducing of information onto/from the disc; a driver unit for moving the optical head in a radial direction of the disc; and a unit mechanism chassis 8 for supporting those thereon, fixedly, wherein the spindle motor is constructed with a rotational drive means made of a magnetic circuit, a rotor portion and a rotation shaft, which define a rotation body, and a spindle motor attachment plate to hold those thereon, and the spindle motor attachment plate has a semi-circular shaped plate configuration in a part thereof, nearly fitting to an outer diameter the rotor portion, in a direction where the optical head is provided, and has a step-like structure in thickness direction of the plate thereof, within a semi-circular shaped region with respect to a line connecting between corner portions on both ends of that semi-circular shape, and also bridging over that li

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: According to one embodiment, a recording medium drive includes a stator, a rotor, recording disks, an annular spacer, and an annular thin plate. The rotor is rotatably supported by the stator. The recording disks are mounted on the rotor. The annular spacer is mounted on the rotor between the recording disks. The annular thin plate is mounted on the rotor between one of the recording disks and the annular spacer. The thin plate includes a first thin plate, a second thin plate, and a viscoelastic body. The first and second thin plates are formed of a hard resin plate or a metal plate. The first thin plate is adjacent to either the one of the recording disks or the annular spacer, and the second thin plate is adjacent to the other. The viscoelastic body is interposed between the first thin plate and the second thin plate.

Abstract: Provided is a fluid bearing device with a hub part having high molding precision and dimensional stability and capable of being produced at low cost. An annular gate (14) is formed at a portion of a cavity (15) corresponding to an outer peripheral edge portion of a lower end surface (10c1) of a flange part (10c), and a molten resin (P) is filled into the cavity (15) through the annular gate (14) to form a hub part (10) made of resin. The hub part (10) molded by the injection molding exhibits a radial resin orientation through an entire periphery thereof. Further, an annular gate trace (16) is formed at the outer peripheral edge portion of the lower end surface (10c1) of the flange part (10c) of the hub part (10).

Abstract: A fluid dynamic pressure bearing device includes a shaft, an annular member, and a rotating member. The annular member is fixed to or seamlessly defined with the shaft and is radially opposed to the rotating member. The annular member and the rotating member are covered with a seal member. A first gap is defined between the seal member and the annular member. A second gap is defined between the rotating member and the seal member. A third gap is defined between the annular member and the rotating member. The first gap preferably has a width smaller than that of the second gap but greater than that of the third gap.

Abstract: A method for manufacturing a bearing mechanism includes the steps of: (a) setting a position of an annular member relative to a center axis; (b) moving the annular member toward an opening of a sleeve housing through a shaft by pressing and elastically deforming a bottom portion of the sleeve housing; (c) releasing the pressing to restore the bottom portion to its original shape; and (d) fixing the annular member to the sleeve housing. Herein, the step (b) is performed by arranging the annular member within the sleeve housing, making one end portion of the shaft received in the annular member contact an inner bottom surface of the sleeve housing or with a thrust member disposed thereon, and making the annular member contact the shaft in a direction leading from the opening to the bottom portion of the sleeve housing.

Abstract: The present invention provides a disk drive device that can appropriately clamp a disk by means of magnetic force even when the disk drive device is very small. A clamping magnet 16 on which a disk 20 is mounted is attached to a turntable portion 15b of a rotor frame 15 to attract the disk 20. The clamping magnet 16 is configured so that the disk 20 can be mounted on the clamping magnet 16. An area of the rotor frame 15 from the turntable portion 15b to a boss portion 15a is composed of a ferromagnetic material.

Abstract: A bearing mechanism includes a cylindrical bottom-closed sleeve unit; a shaft unit radially supported by the sleeve unit via a lubricant; and an elastic thrust plate on an inner bottom surface of the sleeve unit to contact an end portion of the shaft unit at a position on a central axis to rotatably support the shaft unit. The shaft unit has a first contact portion, and the sleeve unit has a second contact portion. The contact portions are so arranged that, when a force acting from above the inner bottom surface is applied, movement of the shaft unit is restrained by the contact portions making contact with each other. Further, a distance between the contact portions prior to the force being applied is smaller than the displacement of the shaft unit at which the thrust plate gets so pressed by the shaft unit to be permanently deformed.

Abstract: Using a simple and inexpensive method, a reliable spindle motor having a simple and inexpensive structure is afforded, in which contact failure of the FPC does not occur even when the motor undergoes external impact. An extending portion is provided radially outer side of an annular recess of a base. The extending portion has a step whose radially outer side is higher, and a through hole formed such as to pass through the base from its inside to outside. A FPC is disposed on an upper surface of a stator. The FPC is fixed to a lower surface of the base through the through hole. The bending height and the bending angle of the FPC are minimized by providing the step having appropriate height so that the FPC is not easily peeled off even when subject to external impact.

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: A fluid dynamic bearing device includes a sleeve having a bearing hole into which a shaft is inserted, the sleeve rotatably supporting the shaft to make relative rotation about a center axis and a bearing housing made of a cold-rolled steel plate or a galvanized steel plate, the sleeve being received within the bearing housing. The bearing housing is filled with lubricating oil mainly composed of ester. A radial dynamic pressure bearing portion is provided between an outer circumferential surface of the shaft and an inner circumferential surface of the sleeve, the radial dynamic pressure bearing portion having radial dynamic pressure grooves for holding the lubricating oil as working fluid and for inducing a fluid dynamic pressure in the lubricating oil during the relative rotation. At least a surface region of the bearing housing remaining in contact with the lubricating oil is coated with a layer mainly composed of nickel.