Abstract: Method and its enabling device for remote wireless micro-latching for security purposes, comprising at least one user or controller, one mobile communication device, and one secured device, whereas said user is enabled to open or close a micro-latch in said a secured device, for instant a safe box or a medical cabinet, allowing access to secured content, including money, ID card, checks, as well as medicine. Also disclosed is a multiplicity of said devices and their preprogrammed remote control by computer or mobile app. The micro-latching can be amplified to macro-latching, for instance by a micro-solenoid switching a high power electrical switch bank or relay, which in turn initiates industrial processes.

Abstract: A hard disk drive includes a base deck, a cover coupled to the base deck to create an internal cavity, and a testing assembly coupled to the cover. The testing assembly includes a housing and is arranged to expose an organic material, for example grease or oil, to the internal cavity.

Abstract: An external rotor motor includes: a shaft, an insulator and a core. The insulator is coupled with an outer peripheral surface of the shaft, the core is arranged on an outer periphery of the insulator, and the insulator is formed between the shaft and the core, so that no electrically conductive route can be formed between the core and the shaft. A rotor has a housing rotatably coupling with the shaft, with an inner peripheral wall of the housing having a permanent magnet module.

Abstract: A device comprising a base body is provided. A stator pack of an electric machine is connected to the base body by means of a connecting structure. The electric machine includes a rotor which cooperates electromagnetically with the stator pack and is rotatably mounted relative to the stator pack such that the rotor can rotate about the rotational axis. The stator pack is fixed by means of the connecting structure relative to the base body. The stator pack includes a plurality of stator sheets which are stacked on top of each other when seen in the direction of the rotational axis. Electromagnetically inactive first intermediate layers are arranged at least between certain stator sheets. The first intermediate layers are components of the connecting structure. Torque exerted upon the rotor by means of the stator pack is transferred in the connecting structure by means of the layers.

Abstract: A motor includes an armature arranged radially outside a rotor magnet, and a casing configured to fix the armature and hold upper and lower bearings configured to rotatably support a shaft at a radial center thereof. The armature includes a stator core, an insulator arranged to cover the stator core, coils each of which is defined by a conducting wire wound around a separate one of magnetic pole teeth with the insulator intervening therebetween, and passage lines each of which is arranged circumferentially between adjacent ones of the magnetic pole teeth to electrically connect one of the coils and another one of the coils with each other. The insulator includes magnetic pole tooth insulating portions arranged to cover a separate one of the magnetic pole teeth; and a core back insulating portion integral with each magnetic pole tooth insulating portion.

Abstract: In certain embodiments, an apparatus includes a basedeck; a motor coupled to the basedeck and having a rotatable hub; and first, second, third, fourth, and fifth discs coupled to the hub. Three of the five discs are biased against the hub in a first direction and two of the five discs are biased against the hub in a second direction. In certain embodiments, a method includes biasing at least three discs against a hub in a first direction and biasing at least two discs against the hub in a second direction.

Abstract: The invention relates to the spindle motor for driving a hard disk drive, comprising: a stationary motor component (10, 12, 16, 18), a rotary motor component (14) rotatably mounted relative to the stationary motor component using a fluid dynamic bearing system, a bearing gap (20) disposed between the stationary motor component and the rotary motor component and filled with a bearing fluid, having at least one open end, at least one sealing gap (34) for sealing the open end, at least one cover cap (30) for covering the sealing gap, which is secured to the rotatable motor component, a disk clamp (44) for attachment of at least one magnetic storage disk (48) on the rotatable motor member and an electromagnetic drive system (40, 42) to drive the rotatable motor member. The disk clamp (44, 156) is centered on a peripheral surface of the cover cap (30, 118).

Abstract: A linear actuator comprising a cabinet (1), an electric motor (2), a transmission (4), a gear housing (11), a spindle nut (6), a spindle (5), the actuator being furnished with an opening (20) in the gear housing (11), where a gear wheel power take-off (21) is accessible and may be equipped with optional equipment. The gear wheel power take-off (21) is constructed as a tooth gearing on a planetary wheel holder (16) in a planetary wheel and transfers a movement to the optional equipment, which is proportional to the movement of the spindle nut during its travel on the spindle.

Abstract: A disk-rotating motor includes a rotor section including a rotor magnet attached to a rotor frame and a shaft fixed to a center of the rotor frame, and a stator section including a shaft-bearing which bears the shaft, wherein the stator section includes the shaft-bearing, a shaft-bearing housing which holds the shaft-bearing, a thrust plate which bears the shaft in an axis direction, a stator core which is arranged to face the rotor magnet and provided with wire-winding, a core holder which holds the stator core, and a bracket which holds the shaft-bearing housing. The bracket has a projecting part which fixes the shaft-bearing at a central part thereof, an inner diameter part of the shaft-bearing is press-fitted to be tightened to the projecting part, and an outer diameter part of the shaft-bearing housing is adhered to be tightened to an inner diameter part of the core holder.

Abstract: A lead wire guide member is made of an electrically insulating material, and arranged to extend along a lower surface of a base portion. A movement restricting portion is arranged in the lower surface of the base portion. Lead wires are arranged to pass through base through holes to reach the lower surface, and extend along the lower surface to be connected to the circuit board. A spindle motor further includes a sealant arranged between an entire circumferential extent of each base through hole and an entire circumferential extent of the corresponding lead wire. The lead wire guide member includes an inner edge and an outer edge. The inner edge is arranged opposite to the lead wires. The outer edge is arranged to at least face radially outward. The movement restricting portion is in contact with the outer edge of the lead wire guide member.

Abstract: There is provided a base assembly for a motor, the base assembly including: a base supporting rotation of a rotating member of the motor; and a pulling plate provided to the base to thereby prevent excessive floating of the rotating member, wherein the pulling plate includes a body part not in contact with the base and an extension part extended from the body part to thereby contact the base.

Abstract: A rotating device includes: a hub that is rotatably supported by a base, on which a recording disk is to be mounted; a stator core fixed to the base, the core having a ring portion and multiple salient poles that radially extend from the ring portion; and a magnet fixed to the hub, the magnet having multiple magnetic poles arranged along its circumference on its side surface on the salient pole side. The magnet is arranged such that its side surface on the salient pole side faces a side surface of each salient pole and a side surface of a portion of the hub that faces the stator core along a rotational axis direction.

Abstract: A bearing device has two or more bearings each having an inner ring and an outer ring disposed on the same axis. A ring-shaped holder is disposed between the inner ring and the outer ring and has circumferentially spaced-apart rolling element pockets with a concave grease pocket between each two adjacent rolling element pockets. Rolling elements are disposed in a rollable manner in respective ones of the rolling element pockets and a grease is stored in the grease pockets, the grease serving as a lubricant of the rolling element. The grease consists of at least a base oil comprised of aromatic carbon and a thickener, the content of the aromatic hydrocarbon being 70 weight % or more of the grease.

Abstract: A spindle motor includes a shaft arranged to extend in an axial direction, and a base portion arranged to define a portion of a housing, and including a through hole in which the shaft is inserted. A fixing region is defined between an inner circumferential portion of the base portion and a lower portion of the shaft. The fixing region includes a press-fitting region and an adhesion region defined on a lower side of the press-fitting region and in which a seal gap is defined between the inner circumferential portion of the base portion and the lower portion of the shaft. The seal gap is arranged to gradually decrease in radial width with increasing height. The seal gap is arranged to include an adhesive arranged therein over an entire circumference thereof.

Abstract: A spindle motor includes a shaft arranged to extend in an axial direction, and a base portion arranged to define a portion of a housing, and including a through hole in which the shaft is inserted. A fixing region is defined between an inner circumferential portion of the base portion and a lower portion of the shaft. The fixing region includes a press-fitting region and an adhesion region defined on a lower side of the press-fitting region and in which a seal gap is defined between the inner circumferential portion of the base portion and the lower portion of the shaft. The seal gap is arranged to gradually decrease in radial width with increasing height. The seal gap is arranged to include an adhesive arranged therein over an entire circumference thereof.

Abstract: A base plate of a disk drive apparatus includes a motor base disposed around a central axis and a base body portion extending radially outward of the motor base. The motor base is made of a metallic material of a first type. The base body portion is made of a metallic material of a second type. The base body portion is a casting product in which the motor base is an insert component. An upper protruding portion and a lower protruding portion are defined in one of an outer end portion of a bottom plate portion of the motor base and an inner end portion of the base body portion.

Abstract: A spindle motor includes a flat stator, a rotor magnet arranged above the stator, and a magnetic portion made of a ferromagnetic material. The magnetic portion is positioned lower than the stator and the magnetic portion are axially overlapped with coils. A magnetic attraction force is generated between the magnetic portion and the rotor magnet. Since the magnetic portion is positioned lower than the stator, it is possible to cause magnetic fluxes to efficiently flow between the rotor magnet and the stator. Further, the stator includes a protrusion protruded radially outward beyond an outer circumferential portion of a rotor hub. Accordingly, in a plan view, the stator is positioned radially outward of the rotor hub.

Abstract: There is provided a spindle motor including: a shaft including a body portion and an extending portion extending from an upper portion of the body portion in an outer radial direction; a sleeve rotatably supporting the shaft; a rotor rotating in conjunction with the shaft and having a stopper portion facing an outer circumferential surface of the sleeve; and a cover plate coupled to the sleeve, while maintaining a gap with lower portions of the shaft and the sleeve, wherein the cover plate includes an airtight portion disposed below the shaft and the sleeve, an inner wall portion extending from the airtight portion in an axial direction and coupled to an outer circumferential surface of the sleeve, an outer wall portion coupled to a base member, and an upper wall portion connecting an upper end of the inner wall portion and an upper end of the outer wall portion.

Abstract: A motor includes a base, a bushing, a bearing structure, a stator structure, a rotor structure and a magnetic element. The base has a supporting platform. The bushing is connected with the base. The bearing structure is disposed in the bushing. The bushing is threaded through the stator structure. The rotor structure has a shaft, and the shaft threads through the bearing structure. The magnetic element corresponds to the shaft and is disposed on the supporting platform, and the magnetic element magnetically interacts with the shaft. A fan equipped with the motor is also disclosed.

Abstract: In a spindle motor, a shaft portion includes a columnar portion, an annular portion, and a recessed portion. A cap portion includes a flat plate portion and a projecting portion. The recessed portion includes a first side surface and a second side surface arranged radially outside the first side surface. A lower end portion of the projecting portion is arranged inside the recessed portion. The first side surface is arranged opposite to an inner circumferential surface of the projecting portion with a first region intervening therebetween. The second side surface is arranged opposite to an outer circumferential surface of the projecting portion with a second region intervening therebetween. A bottom portion of the recessed portion is arranged opposite to the lower end portion of the projecting portion with a third region intervening therebetween.

Abstract: A base plate of a disk drive apparatus includes a motor base disposed around a central axis and a base body portion extending radially outward of the motor base. The motor base is made of a metallic material of a first type. The base body portion is made of a metallic material of a second type. Thus, the axial thickness of a portion of the base plate close to the central axis can be significantly reduced and a reduction in the stiffness of the portion can be prevented. Further, the motor base includes a flange portion and a plastic deforming portion. The flange portion and the plastic deforming portion are respectively in contact with at least a portion of both axial end surfaces of an inner end portion of the base body portion. Thus, extraction of the motor base in the axial direction is prevented.

Abstract: A first inner ring and a second inner ring respectively include inner ring rolling surfaces formed so that the external radius of inner end portions is smaller than a first separation distance and formed so as to have an external radius that become larger than the first separation distance, and a first outer ring and a second outer ring respectively include outer ring rolling surfaces formed so that the internal radius of outer end portions is larger than a second separation distance and formed so as to have an internal radius that becomes smaller than the second separation distance, and the first outer ring and the second outer ring are formed integrally with each other to form an outer ring.

Abstract: A disk clamp that can engage a disk hub to couple a disk media to a disk hub, the disk clamp having a body portion, and a groove formed in a surface of the body portion and extending at least in a circumferential direction substantially parallel to at least a portion of the circumference of the disk clamp; and a balance weight installed in the groove formed in the surface of the disk clamp, the balance weight having a quantity of material applied in the groove. A disk drive assembly using the disk hub and a method of correcting a drive imbalance using the disk hub.

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

Abstract: A 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.

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 base unit includes a stator and a base member including a first recess portion, a second recess portion, and at least one through-hole. The first recess portion is arranged on an upper surface of the base member to surround the hole portion and depressed toward the lower surface thereof. The second recess portion is arranged radially outward of the first recess portion and depressed toward a lower surface thereof. The through-hole is arranged inside the first recess portion to extend through the base member. The second recess portion includes a protrusion portion and a third recess portion. The protrusion portion protrudes from the lower surface of the base member toward the upper surface of the base member. The third recess portion is depressed from the lower surface of the base member toward the upper surface of the base member and positioned at the opposite side from the protrusion portion.

Abstract: 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.

Abstract: A motor unit for use in a disk drive apparatus includes a motor portion, a housing member including a through hole defined therein, and a circuit board. The motor portion includes a rotating portion, a base portion, and a stator fixed to the base portion. The circuit board is arranged to extend from an outside of the motor portion to an inside of the stator through a gap defined between the stator and the base portion. The circuit board includes a connection portion arranged radially inward of the stator. A plurality of lead wires of the stator is connected to the connection portion.

Abstract: A disk rotating motor is provided with: a stator including a stator core and a bracket for fixing the stator core; a rotor that can be rotated with respect to the stator and includes a shaft; and a bearing that rotatably supports the rotary shaft on the outer diameter side of the rotary shaft. The bracket includes a cylindrical portion extending along the shaft and a folded portion formed by folding the upper end of the cylindrical portion onto the outer diameter side. The bearing is fixed to the inner circumferential surface of the cylindrical portion whereas the stator core is fixed to the outer peripheral surface of the folded portion.

Abstract: A base unit includes a stator, a wiring substrate, and a base portion. The base portion includes a tubular portion, a first recess portion surrounding the tubular portion, and first through-holes arranged within the first recess portion. The wiring substrate includes a connection portion arranged on an upper surface of the base portion and provided with lands, a power feeding portion arranged on a lower surface of the base portion, and an extension portion arranged to interconnect the connection portion and the power feeding portion. A first bonding layer is arranged between the connection portion and a bottom of the first recess portion to bond the connection portion and the bottom of the first recess portion. A second bonding layer is arranged between the power feeding portion and the lower surface of the base portion to bond the power feeding portion and the lower surface of the base portion.

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

Abstract: There are provided a rotating member assembly and a spindle motor including the same. The rotating member assembly includes: a rotating member including a shaft and a hub fixed to an upper portion of the shaft, wherein perpendicularity of the hub with regard to the shaft at a position spaced apart from the center of rotation of the shaft in an outer diameter direction by an axial length or more for which the shaft is fitted into the sleeve is less than double a distance of a gap of a bearing clearance formed by fitting the shaft into the sleeve.

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

Abstract: A spindle motor includes a shaft arranged to extend in an axial direction, and a base portion arranged to define a portion of a housing, and including a through hole in which the shaft is inserted. A fixing region is defined between an inner circumferential portion of the base portion and a lower portion of the shaft. The fixing region includes a press-fitting region and an adhesion region defined on a lower side of the press-fitting region and in which a seal gap is defined between the inner circumferential portion of the base portion and the lower portion of the shaft. The seal gap is arranged to gradually decrease in radial width with increasing height. The seal gap is arranged to include an adhesive arranged therein over an entire circumference thereof.

Abstract: An apparatus and method are provided for stiffening a base plate of a spindle motor to improve shock resistance and vibration response, and thereby increase reliability and performance of a disc drive memory system. A stiffener tab for stiffening a base plate is connected to the base plate, extends from the base plate, and is dimensioned to fit adjacent to a stator tooth. Stiffening of a base plate is especially useful in the case of stamped base plate designs that typically have uniform thickness, whereas cast base plate designs are formed with thicker sections. In an aspect, the present invention stiffens a motor cup portion of the base plate, and replaces stiffness lost by removal of material from the base plate to form holes for recessing a stator into the base plate. Axial and angular displacement of a spindle motor during shock events and vibration are decreased.

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

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

Abstract: There is provided a base assembly for a motor, including: a base member having a shaft system of the motor mounted therein; a pulling plate bonded to the base member to prevent excessive floating of the motor; and at least one adhesive filling part formed in the pulling plate, and providing an adhesion space for an adhesive used for bonding the pulling plate to the base member to increase a contact area with the adhesive.

Abstract: 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.

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: A storage disk drive motor 12 includes a stator unit 2, a rotor unit 3, a shaft 41 arranged in a coaxial relationship with a center axis 9, a sleeve unit 22 including a flange portion 223, and a base member 21, having a through-hole, fixed to the sleeve unit 22 by caulking. The flange portion 223 includes a flange lower surface 223b making contact with an upper surface 21a of the base member 21 and a jut 24 protruding downwards from a radial inner side of the flange lower surface 223b. The jut 24 includes a first outer circumferential surface 241 opposed to the inner circumferential surface 21c of the base member 21, a second outer circumferential surface 242 positioned below the first outer circumferential surface 241, and a groove 243 radially inwardly indented from the first outer circumferential surface 241 and the second outer circumferential surface 242.

Abstract: A spindle motor structure is disclosed having a structure incorporating a spindle motor, a driving substrate, and a base on which the spindle motor and the driving substrate are installed. The spindle motor includes a stator having a core wound with a coil and a rotor rotating about the stator. The driving substrate is aligned at an outer periphery of the rotor and soldered with driving control parts of the spindle motor including a plurality of circuit parts including a driving integrated circuit and the like. The spindle motor is assembled with or dissembled from the base independently from the driving substrate.

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 fluid dynamic bearing includes an auxiliary bearing portion, a first radial bearing portion and a second radial bearing portion arranged along an axial direction of the fluid dynamic bearing, wherein the auxiliary groove formed in the auxiliary bearing portion is shallower in depth than the radial dynamic pressure groove formed in the first radial bearing portion, and wherein a gap size in the auxiliary bearing portion is set to be equal to or larger than a gap size in the radial bearing portions.

Abstract: A bearing mechanism includes a shaft, a sleeve portion, a thrust portion, and a cover portion. Lubricating oil is arranged in a communicating channel in the sleeve portion, a thrust gap between the sleeve portion and the thrust portion, and a tapered gap between an outside surface of the thrust portion and the cover portion. A lower end opening of the communicating channel is defined in an outer circumferential portion of a lower surface of the sleeve portion radially outward of the thrust gap. A radially outermost portion of the thrust portion is arranged either tangent to a wall surface of the communicating channel or closer to a central axis than the wall surface. The tapered gap is arranged closer to the central axis than a radially outermost point of the wall surface. The outer circumferential portion and the cover portion define a guide gap therebetween.

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

Abstract: 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: A disk drive apparatus includes at least one disk, a head-arm assembly, and a controller circuit. The head arm assembly includes at least one read/write head. The head-arm assembly is movable to enable the read/write head to access a writable surface of the disk. The controller circuit also causes the read/write head to record data on the writable surface of the disk in a write append format.