Abstract: A gear motor comprising a reduction gear train and a three-phase electric motor comprising a stator formed of a stack of sheets and 3*k electric coils and a rotor having 5 k*N pairs of magnetized poles, with k=1 or 2, the stator having two separate angular sectors alpha 1 and alpha 2, which are centered on the center of rotation of the motor and comprise an alternation of notches and 3*k*N teeth, which are regularly spaced and converge toward the center of rotation and define a cavity in which the rotor is arranged, the gear motor being characterized in that N=4 and in that alpha 1 is less than or equal to 180° and comprises all of the coils of the motor.

Abstract: Methods are described for forming a mounting surface on a slider body. In one method, an adhesion layer can be deposited on a top surface of a slider body. A first photolithography cycle deposits a first metal layer having a first thickness of at least 8 ?m. A second photolithography cycle deposits a second metal layer having a second thickness of at least 8 ?m over the first metal layer. The first and second layer form a mounting support on the top surface. In another method, the top surface is etched to form a mounting support.

Abstract: A camera module includes a housing, a lens, an assembly, a terminal, and an electronic component. The housing includes a front surface part, a rear surface part on the opposite side to that, and a side surface part connecting the front surface part and the rear surface part. The lens is exposed from the front surface part. The assembly includes an image sensor and is located on the rear surface part side relative to the lens. The terminal is located at the rear surface part for connection with an outside part. A flexible board includes a part extending from the assembly toward the terminal. The electronic component is mounted on the flexible board.

Abstract: A fixing device includes a pair of bushes, a pair of bearing members, a support plate, and a fixing frame. The pair of bushes are attached to both end parts of a rotation shaft of a heating rotating member. The pair of bearing members supports the bushes in a rotatable manner. The support plate has insertion hole into which the bearing member is inserted so that the bearing member is fastened, and a positioning pin. The fixing frame has a positioning hole into which the positioning pin is inserted. The support plate is provided with a distortion prevention part for preventing occurrence of distortion around the insertion hole when the positioning pin is inserted into the positioning hole. At least a part of the distortion prevention part is positioned within a first area.

Abstract: A control system for controlling a synchronous motor having a magnet in a rotor includes an inverter configured to output an AC current for driving the motor, a gate command generating unit configured to generate a gate command for controlling the inverter, a current detecting unit configured to detect the AC current output by the inverter, a magnetic pole position estimating unit configured to estimate a magnetic pole position based on the AC current detected by the current detecting unit and generate an estimation signal, a current command generating unit configured to generate a current command and an estimation command for controlling the inverter to output an AC current with a predetermined level, and a magnetic polarity determination unit configured to determine the polarity of the magnet based on the estimation signal.

Abstract: The present invention relates to an anti-separating structure of sensing magnet for motor, wherein, the coupling between the plate and the sensing magnet is effected by the bent unit formed at the plate and a separate cap member to reinforce the coupling power to axial, horizontal and rotational directions by the mechanical structure, and to improve a structural stability and operational reliability, the structure including a plate formed with a plate insertion hole that vertically penetrates the plate; a sensing magnet formed with a magnet insertion hole corresponding to the plate insertion hole; and a plate-shaped cap member including a coupling lug coupled by penetrating the plate insertion hole and the magnet insertion hole.

Abstract: A spindle motor for a hard disk drive includes a base and a bearing assembly coupled to the base. The bearing assembly includes a sleeve configured to rotatably support a shaft therein. A rotor hub is affixed to the shaft so as to be rotatable with the shaft about a rotational axis. A stator is arranged in between the rotor hub and the base. A first magnet is arranged over the stator and on a bottom surface of the rotor hub. In particular, the rotor hub includes a body portion, a peripheral wall portion extending from the body portion in a direction towards the base, and a flange portion having a disk seating surface configured for supporting one or more disks thereon. The peripheral wall portion is configured to at least partially surround the stator in a radial direction. There is also provided a method of fabricating the spindle motor and a hard disk drive incorporating the spindle motor.

Abstract: A lightweight radio/CD player for vehicular application includes a case and frontal interface formed of polymer based material molded to provide details to accept audio devices and radio receivers, as well as the circuit boards required for electrical control and display. The case and frontal interface are of composite structure, including an insert molded electrically conductive wire mesh screen that has been pre-formed to contour with the molding operation. The wire mesh provides shielding and grounding of the circuit boards via exposed wire mesh pads and adjacent ground clips.

Abstract: A spindle includes a fixed member, a hub rotatably attached to the fixed member, and a bearing between the rotatable hub and the fixed member. The bearing including a bearing lubricant. A seal reduces migration of the bearing lubricant away from the bearing. The seal includes an immobile cylindrical surface of the fixed member, and a rotatable cylindrical surface of the hub. One of these surfaces includes a plurality of grooves. The immobile cylindrical surface and the rotatable cylindrical surface are concentric about the hub rotation axis. The rotatable cylindrical surface faces and is separated from the immobile cylindrical surface by a gas-filled radial clearance of not less than 50 microns.

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: 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 disc spindle provides removal of particulates generated by internal parts of mechanisms, including the disc clamping mechanism, air bearing rotor, and other moving parts provides a port that is coupled to a vacuum system to remove particulate from the areas in which they are generated. In other aspects of the invention, vacuum evacuation of rotary and other bearings in a mechanical system employed in a clean room environment are prevented from contaminating the environment by removing particulate at the locations in which it is generated by friction, contact, or other means such as being introduced from the pressure channel in an air bearing feed.

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: 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 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: 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: An apparatus for inhibiting oil leakage is disclosed by which the oil leakage can be effectively inhibited with a simple structure, where the apparatus is extensively formed along an outer periphery of a rotation shaft at a position higher than at least an upper end of a bearing and is formed with an oil barrier that restrains oil rise.

Abstract: A vibration motor is provided, comprising a case having an upper case and a lower case which are coupled to each other; a shaft installed in the case while being supported by the case; a rotor rotatably coupled with the shaft; a stator arranged around the shaft; a first substrate installed on an upper surface of the lower case; and a second substrate coupled to a lower surface of the lower case and electrically connected to the first substrate. The lower case has a first opening and the first substrate is electrically connected to the second substrate through the first opening.

Abstract: A brushless motor includes a motor drive unit, a circuit board arranged to drive the motor drive unit having through holes formed in the upper surface and the lower surface; and a motor attachment plate including a plate-shaped base portion and plate-shaped fixing portions to fix the circuit board in place. Herein, each fixing portion includes a support portion for making contact with a surface of the circuit board; an arm portion bent in a direction that is substantially parallel to the rotational axis; and a protrusion portion inserted into a through hole, having at least one overhang extension protruding from the through hole. The overhang extension of the protrusion is bent in a direction that is substantially perpendicular to the rotational axis.

Abstract: A spindle motor and a disk drive device are provided that have a high operation efficiency of the motor, that does not leak oil, and that has an improved stability by decreasing a runout component in the direction of the rotation axis. The spindle motor includes a rotor hub (20) composed of a disk-like flange (201) and a cylinder-shaped shaft (203); a ring-shaped rotating magnet (16) fastened on one main surface of the flange (201); an armature (14) facing the rotating magnet (16); a sleeve (80) rotatably supporting the shaft (203); and a chassis (15) fixing the armature (14) and the sleeve (80).

Abstract: The present invention provides a rotary electric machine, in which it is possible to reduce the dimension of a casing in a direction along a rotation center line. The rotary electric machine comprises a magnet rotor 2 rotating about a rotation center line 1 and one or more magnetic sensors 11 for detecting leakage flux leaking out of the magnet rotor 2. The magnet rotor 2 and a stator 3 are received in a casing 4. A sensor receiving portion 12 for receiving the one or more magnetic sensors 11 is disposed in an outer wall portion of a side wall of the casing 4 located in an extending direction of the rotation center line 1 of the magnet rotor 2. The one or more magnetic sensors 11 are received in the sensor receiving portion 12. The sensor receiving portion 12 is disposed in a position that allows the one or more sensors to detect leakage flux leaking out of the magnet rotor 2.

Abstract: With a spindle motor 20, a stator core 8 comprises a plurality of salient pole components 51 that are formed in a radial shape, are wound with a stator coil 9, and are disposed at a uniform angle except for a non-equiangular pitch portion, an circular outer peripheral yoke 52 formed so as to be continuous with the outer peripheral side of the salient pole components 51, a cut-out 55 which is formed by cutting out part of the outer peripheral yoke 52 in an approximate sector-shape except in the non-equiangular pitch portion of the salient pole components 51, and a compensating pole plate 11 which is provided in the cut-out 55 along the ends on the inner peripheral side of the non-equiangular pitch portion where the salient pole components 51 are formed.

Abstract: A bearing support for use in a motor includes a tube (50) having an exterior surface and an interior surface. A plurality of first protrusions (52) on the exterior surface of the tube (50) are provided for engaging a stator (2) of the motor mounted around the tube. A plurality of second protrusions (55) on the interior surface of the tube (50) are provided for engaging a bearing (60) of the motor. The first and second protrusions are alternated along a circumferential direction of the tube.

Abstract: Disclosed is a recording disk cartridge which improves its assembly and production capacities, as well as the flexibility of the design. The recording disk cartridge that has a cartridge case including flexible recording disk media in an integrally rotatable fashion, a lower plate forming a lower wall of the cartridge case, the lower wall being placed parallel to the recording disk media, one or more inner plates being fixed on the lower plate with being stacked and partitioning the recording disk media, and an upper plate being fixed on the inner plates and forming an upper wall of the cartridge case. Furthermore, the lower plate incorporates at least one of a shutter lock mechanism and a write protect switch mechanism. The shutter lock mechanism blocks a shutter from being opened, and the write protect switch mechanism prevents data from being erased accidentally from the recording disk media.

Abstract: A head gimbal assembly (HGA) has an improved interconnection between a head slider and a suspension of the HGA. The interconnection is achieved by using a reverse surface of an air bearing surface of the head slider as bonding surface to provide more space for arranging more slider electrical bonding pads thereon. The head slider is mechanically and electrically connected to the suspension at the bonding surface to have good performance on shocking conditions. The suspension further has an attitude control layer located between the head slider and the suspension. The attitude control layer serves as a datum plate for the head slider lying thereon and supporting the head slider so as to ensure the head slider a good attitude and reduce variation of slider flying height. The present invention also discloses a magnetic disk drive with the improved HGA and a fabricating method for the HGA.

Abstract: In a disk chucking mechanism for use in a flexible disk drive adopting a spindle motor (300) of a Hall sensor-less method, a driving pin (317A) freely received in a driving oval hole (46b) of a flexible disk (40) has a shape (shape of fan) where a catch factor portion is cut so that the driving pin (317A) is not in contact with an inner edge of the driving oval hole (46b) as much as possible when a rotor (310A) of the spindle motor (300) rotates in the opposite direction (counterclockwise).

Abstract: Radial dynamic pressure grooves are provided in a first region 4A and a second region 4B on the side of a fixed shaft 2. A vent 2D is provided inside the top end 2A of the fixed shaft 2. The vent 2D connects spaces over and under a flange 3 to each other. The flange 3 in an annular shape is fixed at the top end 2A of the fixed shaft 2. Thrust dynamic pressure grooves 3A and 3B are provided on the surfaces of the flange 3. A circulation hole 3C is provided in the flange 3, and connects spaces over and under the flange 3 to each other. A sleeve 4 revolves around the fixed shaft 2. A thrust plate 6 in an annular shape is fixed at the top of the sleeve 4 and opposed to the flange 3. The first region 4A, the second region 4B, the thrust dynamic pressure grooves 3A and 3B, and the circulation hole 3C of the flange 3 are filled with a lubricant 7.

Abstract: A base plate for a spindle motor is provided defining a minimal axial gap with a relatively rotatable magnet. In an example, a surface of the base plate is positioned at 0.1 mm from an adjacent surface of a relatively rotatable magnet. The base plate is comprised of a composite material such that stiffness is improved and acoustic vibration is reduced, while maintaining low power consumption and a fast start-up time. A first material, being a nonmagnetic material is employed adjacent to a motor magnet, and a second material having a preferred stiffness is employed at a greater radial distance from the magnet than the radial distance between a stator and the magnet.

Abstract: A spindle motor structure includes a solenoid coil 1 provided above a flexible board 2 provided at one face of a base plate of FDD to align in a circumferential direction centering on one axis and a turn table covering the solenoid coil 1 and provided rotatably centering on the one axis. The spindle motor structure can provide FDD capable of achieving a reduction in cost by reducing a number of parts of PWB and the like using a silicon steel plate, i.e. silicon steel plate PWB.

Abstract: A method of using a balance clip in a hard disk drive spindle motor for disk pack balance correction provides the balance clip with one end that is offset from the circular shape of the balance clip. The offset end is located opposite the precise bent tab that provides tooling engagement in the balance clip. The offset end of the balance clip is offset at a radius that is less than the radius of the balance clip, or at a lesser radial offset from the circular shape. The edge of the offset end does not make contact with the groove in which the balance clip is seated. This design eliminates scratching between the offset end and motor hub, and reduces friction and particle generation during clip adjustment in the disk pack balancing process.

Abstract: A brushless motor includes a highly reliable thrust-receiving member that simplifies the machining and assembling of parts and prevents deformation of the bearing and leakage of lubricating oil. A stator base has a cylindrical portion serving as a base portion of a bearing housing of the motor. The cylindrical portion is integral with the stator base. A sleeve bearing is pressed in and mounted in a fixed condition on the inner side of the cylindrical portion. A stator core consisting of a conductive wire is mounted in a fixed condition on the outer side of the cylindrical portion, thereby forming a stator. A thrust-receiving portion for the rotary shaft is molded integrally with the stator base at the opening of the cylindrical portion by outsert and resin integral molding, this thrust-receiving portion serving to receive the end of the rotary shaft opposite to the output end thereof.

Abstract: A securing surface of a housing comprises a deformation region, which deforms radially outward by a predetermined quantity during press fitting of a thrust member, and another region. The deformation region has a tapered shape that gradually reduces in diameter in the downward direction, and is receded radially inward relative to the other region of the securing surface, by an amount equivalent to the amount of outward deformation thereof during press fitting. When the thrust member is press fitted into the inner periphery of a press fitting portion of the housing, the securing surface of the housing becomes substantially straight along entire axial region L thereof.

Abstract: A radial winding stator structure for a single phase motor is composed of plural silicon steel sheets that are stacked together and have the same structure. Each of the silicon steel sheets includes a hub and six poles. Each pole is radially extended from a circumference of the hub to form a radially extended portion, and tangentially expanded at a terminal of the radially extended portion to form a tangentially extended portion. The hub and the poles are one-piece made, the radially extended portions of each of the poles are stacked to form a pole bobbin of the radial winding stator structure, the tangentially extended portions of each of the poles are stacked to form a pole surface of the radial winding stator structure, and an electrically conductive wire is wound around all of the pole bobbins.

Abstract: A flexible disk drive includes a notched portion at a main frame portion arranged with a motor, a sub board includes a cut groove at an end portion thereof and a wire extended from the motor is held by the cut groove of the sub board and is connected to the main board. Thereby, there can be provided FDD capable of achieving a reduction in cost by a reduction in a number of parts and simplification of a structure thereof.

Abstract: Permanent electro-conductive connection is achieved between a bearing component and a baseplate/flange by providing at least one solid-state contact element between the baseplate/flange and the bearing component. The contact element establishes an electric contact between these parts by exercising mechanical force on the baseplate/flange and/or the bearing component. Alternatively, at least one welding seam may be formed between the baseplate/flange and the bearing component to establish the electro-conductive connection.

Abstract: A combination structure of a motor has a base board, a printed circuit board and at least one sensing unit. The base board is used for placing a stator and a rotor and has at least one first assembly hole. The printed circuit board is connected to the base board and has at least one second assembly hole. The sensing unit is used for sensing a magnet of the rotor. The second assembly hole of the printed circuit board is placed corresponding to the first assembly hole of the base board for commonly containing the sensing unit so that an axial height of the motor is decreased.

Abstract: A main frame has a size where only high precision parts are mounted thereon and has structure where a front portion of a frame is deleted. A lower cover, which covers a lower surface of the main frame, has a function as a sub-frame mounting low precision parts corresponding to the front portion of the deleted frame, thereby playing a role as one frame by a combination of the main frame and the sub-frame of the lower cover.

Abstract: A magnetic disk cartridge comprising a housing with space, and a magnetic disk rotatably held in the space of the housing. The magnetic disk includes a flexible magnetic recording medium, and at least one rigid ring mounted on the circumferential edge portion of the magnetic recording medium.

Abstract: A combination of a base and an axle tube is provided for a motor. The base includes a tubular body and an axial hole through which the axle tube extends. A flange extends upward from a peripheral edge delimiting the axial hole. At least one positioning groove is defined in an inner periphery of the flange. The axle tube includes at least one protrusion on an outer periphery thereof for engaging with the positioning groove of the base. At least one resilient hook rod is formed in the tubular body of the axle tube and has a hook for securely retaining a stator around the axle tube and for securely retaining at least one bearing in the axle tube.

Abstract: A flat motor is composed of a rotor 1 provided with a driving magnet 3 in a ring shape and a shaft 8, and a stator 5. The stator 1 is composed of a stator yoke 6 provided with a bearing mounting section 12 for mounting a bearing 10 for holding the rotor 1 and a driving coil mounting section 13 for mounting a plurality of driving coils 4 disposed in conjugating with the outer side of the bearing mounting section 12. The plurality of driving coils 4 is disposed in a concentric circle with facing towards the driving magnet 3. The bearing mounting section 12 is formed flat in a circular shape with centering the shaft 8.

Abstract: The stop ring having a surface nearly vertical to the rotational center axis, which is projected at the inner periphery of the hollow cylinder of the rotor section, and the stepped surface of the fixed shaft secured on the chassis are opposed to each other with a predetermined slight clearance provided therebetween. The clearance is filled with magnetic fluid, and further, a permanent magnet is disposed on the chassis, opposing to the other surface of the stop ring.

Abstract: A chucking device for a magnetic disk that includes a substantially disk-shaped bearing and a drive arm extending in a rear side of a rotor yoke along a circumferential direction and loosely suspended from and held by a rotor yoke on both ends. An inner peripheral surface for restraining movement toward a bearing is formed at the drive arm, and a drive pin loosely passing through a drive pin through hole of the rotor yoke to extend upward and loosely inserted into a drive hole of a magnetic disk is formed at a front part of the drive arm in a rotor yoke rotation direction. When the rotor yoke having the magnetic disk placed thereon is rotated, the inner peripheral surface of the drive arm comes away from the bearing, and the drive pin comes in contact with a front edge and an outside edge of the drive hole.

Abstract: The rotational balance by weight of a rotational driving apparatus for a disk is adjusted in a state in which a hub or a dummy member equivalent to the hub is fixed onto a turntable while a motor thereof is driven. When the hub is mounted on the turntable, rotation with excellent weight balance can be achieved, resulting in prevention of vibration due to imbalance of weight.

Abstract: A motor rotatably driving a flexible disk has a rotor having an external peripheral side surface on which an index detection magnet is mounted. A main circuit board mounts a control circuit for carrying out a driving control of the motor and extends in a direction perpendicular to a rotation axis of the motor. Attached to the main circuit board, a sub circuit board extends in a direction in parallel with the rotation axis of the motor at a position close to the external peripheral side surface of the rotor. Mounted on the sub circuit board, an index detection Hall element has a magnetic field detection surface which is disposed so as to oppose to the external peripheral side surface of the rotor.

Abstract: A disk drive device includes a protective case having an upper case and a lower case. The disk drive device has a form such that the disk drive device can be inserted into and removed from a PCMCIA port of a computer. The disk drive device has an output connector located at one end of the protective case so that the input/output connector can connect with a PCMCIA connector of the computer when the disk drive device is inserted in the PCMCIA port. Information from the computer can thus be stored on the disk drive device, or information from the disk drive device can be read into the computer.

Abstract: In a floppy disk drive having a main frame in which a floppy disk is inserted and a DD motor for rotatably driving the floppy disk inserted in the main frame, the floppy disk drive has a motor frame for mounting the DD motor thereon that is constituted by one piece integrated by the main frame. Preferably, the motor frame part may have a drawn-shape obtained by drawing the main frame. In addition, the floppy disk drive has an electronic processing arrangement for a frequency generation pattern. The electronic processing arrangement gives play to a function equivalent to the frequency generation pattern required to control the DD motor.

Abstract: A recording disk drive motor is disclosed which is employed in a recording disk drive that retains a removable recording disk that has a diameter of 30 mm or less, as well as a method of manufacturing a stator core used in the same. The core back of the stator core in the motor has an arc shaped inner circumferential surface therein that is offset from the center thereof. The stator core is produced from a laminated body having a stator core, a chuck frame that is integral with and surrounds the stator core, and connector arms that connect the stator core and the chuck frame and integral therewith. After the windings are wound around the stator teeth, the stator core is cut from each connecting arm and the stator core is removed from the chuck frame.

Abstract: A positioning device for a prestressing magnet of a spindle motor includes a stator, a positing member, a prestressing magnet, a rotor and a metal casing. Combined with the prestressing magnet, the positioning member is fittingly secured to a generally axially extending surface at a selected position on the stator while the metal casing is secured to the rotor. After combining the stator with the rotor, the prestressing magnet is axially aligned with the metal casing. An axially magnetic force generated between the prestressing magnet and the metal casing maintains balanced rotation of the rotor.

Abstract: A single cone air dynamic bearing motor, including a shaft having a diminishing conical taper surface, a sleeve having a concavity opposite the shaft, and magnetic members to generate magnetic attraction between the shaft end and the sleeve. Grooves are formed on the conical taper surface of the shaft or the sleeve so as to create load capacity when the motor rotates, whereby rotating parts of the motor are supported by the axial components of the load capacity balanced with the magnetic attraction. The motor thereby achieves reduction in thickness, current, and cost, and inhibits non-repeatable runout.