JP2016106524A - Motor for disk rotation and disk drive device equipped with the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a motor for disk rotation capable of being manufactured by a simple method and also to provide a disk drive device equipped with the same.SOLUTION: A motor 100 as a motor for disk rotation includes: a stator 20 including a stator core 21, and a bracket 23 fixing the stator core 21; a rotor 10 which is rotatable against the stator 20 and includes a shaft 13; and a bearing 30 which rotatably supports the shaft 13 in the outer diameter side of the shaft 13. The bracket 23 includes: a cylindrical part 23d extending along the shaft 13; and a folding back part 23e formed by folding the upper end of the cylindrical part 23d back to the outer diameter side. The bearing 30 is fixed to the inner peripheral surface of the cylindrical part 23d, and the stator core 21 is fixed to the outer peripheral surface of the folding back part 23e.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a disk rotation motor and a disk drive device including the same, and more particularly to a disk rotation motor that can be manufactured by a simple method and a disk drive device including the same.

  When recording or reading information on a recording medium on which information such as an optical disk or a magneto-optical disk is recorded, the disk is rotated using a disk drive device. The disk drive device includes a disk rotation motor for rotating the disk. Technologies related to conventional disk rotating motors are disclosed in, for example, Patent Documents 1 and 2 below.

  Patent Document 1 below discloses a brushless motor in which a burring portion that constitutes a bearing housing and a mounting base portion for mounting a motor are integrally formed.

  Patent Document 2 below discloses a spindle motor in which a bracket including an annular recess and a cylindrical opening is integrally formed by press working. The annular recess is recessed in the axial direction, and a stator and a rotor magnet are accommodated therein. A shaft is fitted into the inner periphery of the cylindrical opening.

JP 2002-262540 A Japanese Patent Laid-Open No. 2001-314058

  In recent years, there has been a strong demand for lower prices for disk rotation motors. In order to reduce the price of the disk rotation motor, it is necessary to manufacture the disk rotation motor by a simple method. For example, the number of parts of a disk rotation motor can be reduced, or the method of processing the parts that make up a disk rotation motor can be compared to a press process rather than a relatively complicated (expensive) method such as cutting. It is necessary to use a simple (inexpensive) method. Furthermore, when assembling the parts, it is necessary to adopt a relatively easy (inexpensive) fastening method represented by press-fitting instead of a complicated fastening method, and to maintain assembly accuracy. The conventional technology has room for further improvement in terms of simplifying the manufacturing method.

  The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a disk rotation motor that can be manufactured by a simple method and a disk drive device including the same.

  A disk rotating motor according to one aspect of the present invention includes a stator including a stator core and a bracket for fixing the stator core, a rotor that is rotatable with respect to the stator and includes a rotating shaft, and an outer diameter side of the rotating shaft. The bracket includes a bearing that rotatably supports the rotating shaft, and the bracket is a tubular portion that extends along the rotating shaft, and a folded portion formed in a state where the upper end portion of the tubular portion is folded to the outer diameter side. And an outer edge formed in a state where the lower end portion of the folded portion is folded to the outer diameter side, the bearing is fixed in contact with the inner circumferential surface of the cylindrical portion, and the stator core is the outer circumferential surface of the folded portion The folding position between the folded portion and the outer edge portion is located below the lower end portion of the stator core with a gap from the lower end portion of the stator core, and the folded portion is located on the outer edge from the folded position with the cylindrical portion. Folding position with the part It multiplied with a uniform diameter.

  Preferably, in the above disk rotating motor, the bracket further includes a bottom portion formed in a state where the end portion of the cylindrical portion is bent toward the inner diameter side, and the bottom portion supports one end portion of the rotating shaft.

  Preferably, the disk rotating motor further includes a thrust plate having a contact surface in contact with one end portion of the rotating shaft, and the bottom portion is a first bottom portion in contact with the thrust plate on a surface opposite to the contact surface. And a second bottom portion formed with the first bottom portion bent and surrounding the outer periphery of the thrust plate.

  Preferably, the disk rotation motor further includes a suction magnet that magnetically attracts the rotor.

  In the disk rotating motor, the suction magnet is preferably fixed to the outer peripheral surface of the bearing so as to be in contact with the boundary between the cylindrical portion and the folded portion.

  Preferably, in the disk rotating motor, the attraction magnet is fixed to the outer peripheral surface of the folded portion so as to be in contact with the stator core.

  In the above disk rotating motor, preferably, the stator core and the bearing are opposed to each other in the radial direction with the cylindrical portion and the turned-up portion interposed therebetween.

  A disk drive device according to another aspect of the present invention includes the above-described disk rotation motor and a control unit that controls the drive state of the disk rotation motor.

  ADVANTAGE OF THE INVENTION According to this invention, the disk rotation motor which can be manufactured by a simple method, and the disk drive device provided with the same can be provided.

1 is a block diagram showing a configuration of a disk drive device according to an embodiment of the present invention. It is sectional drawing which shows typically the structure of the disk rotation motor in one embodiment of this invention. It is a section perspective view showing typically the composition of the disk rotation motor in one embodiment of the present invention. 4 is a perspective view showing a configuration of a bracket 23. FIG. It is a figure which shows typically the 1st process of the manufacturing method of the disk rotation motor in the 1st Embodiment of this invention. It is a figure which shows typically the 2nd process of the manufacturing method of the disk rotation motor in the 1st Embodiment of this invention. It is sectional drawing which shows typically the structure of the motor for disk rotation in the 2nd Embodiment of this invention. It is a cross-sectional perspective view which shows typically the structure of the disk rotation motor in the 2nd Embodiment of this invention. It is sectional drawing which shows typically the structure of the disk rotation motor in the 3rd Embodiment of this invention. It is a cross-sectional perspective view which shows typically the structure of the disk rotation motor in the 3rd Embodiment of this invention. It is sectional drawing which shows typically the structure of the disk rotation motor in the 4th Embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  In the following description, “outer diameter side” means the outer diameter side when the rotation axis of the disk rotation motor is centered, and “inner diameter side” means the rotation axis of the disk rotation motor. It means the inner diameter side when it is the center. The “outer peripheral surface” means the outer peripheral surface when the rotation axis of the disk rotation motor is centered, and the “inner peripheral surface” is the inner periphery when the rotation axis of the disk rotation motor is the center. It means the circumference.

  [First Embodiment]

  FIG. 1 is a block diagram showing a configuration of a disk drive device according to an embodiment of the present invention.

  Referring to FIG. 1, the disk drive apparatus according to the present embodiment includes a motor 100 as a disk rotation motor and a control unit 200 that controls the drive state of the motor 100 such as on / off and rotation speed.

  2 and 3 are diagrams schematically showing a configuration of a disk rotation motor in one embodiment of the present invention. 2 is a cross-sectional view, and FIG. 3 is a cross-sectional perspective view.

  With reference to FIGS. 2 and 3, motor 100 mainly includes a rotor 10, a stator 20, and a bearing 30. The rotor 10 is rotatable with respect to the stator 20. The bearing 30 supports the rotor 10 so as to be rotatable with respect to the stator 20.

  The rotor 10 includes a rotor frame 11, a magnet 12, a shaft 13, and a retaining washer 14. The rotor frame 11 prevents leakage of the magnetic field from the inside of the rotor frame 11, and is made of, for example, a magnetic material. The rotor frame 11 includes a turntable portion 11a and a side wall portion 11b. The turntable portion 11a extends, for example, in a direction (lateral direction in FIG. 2) perpendicular to the extending direction of the shaft 13 (hereinafter sometimes referred to as the axial direction). The turntable portion 11a has a circular shape when seen in a plan view. A hole 60 for passing the shaft 13 is provided at the center of the turntable portion 11 a, and the rotor frame 11 is fixed to the shaft 13 at the hole 60. The side wall portion 11b extends from the outer diameter side end portion of the turntable portion 11a toward the bracket 23 of the stator 20 (downward in FIG. 2). The side wall part 11b has a cylindrical shape.

  The magnet 12 is attached to the inner peripheral surface of the side wall portion 11b. The magnet 12 has an annular shape, and regions magnetized in the N pole and regions magnetized in the S pole are alternately provided at regular intervals along the circumferential direction. The magnet 12 is attached to the rotor frame 11 so as to face the stator 20.

  The shaft 13 extends in the longitudinal direction in FIG. 2 so as to penetrate the central portion (the central portion in FIG. 2) of the rotor frame 11. The rotor frame 11 can rotate with the shaft 13 about the shaft 13. The shaft 13 is rotatably supported by a bearing 30 disposed on the outer diameter side of the shaft 13.

  The retaining washer 14 is fitted with the groove 13 a of the shaft 13 in the vicinity of the lower end of the shaft 13 in FIG. 2. The retaining washer 14 prevents the shaft 13 from slipping upward in FIG. 2 by contacting the bearing 30 when the shaft 13 moves upward in FIG. The position of the retaining washer 14 is regulated between the bearing 30 and the third bottom 23c.

  The stator 20 includes a stator core 21 (core), a stator coil 22, a bracket 23, a bottom plate 24, and a thrust plate 25. The stator core 21 is fixed to the bracket 23. Stator core 21 includes a plurality of teeth 21a formed to extend radially from the inner diameter side toward the outer diameter side. The stator coil 22 is wound around each of the plurality of tooth portions 21a. The bracket 23 fixes the stator core 21. The bottom plate 24 is made of a magnetic material, for example, and is fixed to a surface of the bracket 23 on the rotor 10 side.

  FIG. 4 is a perspective view showing the configuration of the bracket 23. (A) is a figure when it sees from the side which faces the rotor 10, (b) is a figure when it sees from the opposite side to the rotor 10. FIG.

  2 to 4, the bracket 23 includes a first bottom portion 23a, a second bottom portion 23b, a third bottom portion 23c, a cylindrical portion 23d, and a folded portion 23e (bracket folded portion). The outer edge portion 23f is included. The cylindrical portion 23d extends in the axial direction. The first to third bottom portions 23a to 23c are formed by bending the lower end portion of the cylindrical portion 23d in FIG. 2 toward the inner diameter side, and support the lower end portion of the shaft 13 in FIG. The first bottom portion 23a is located at a position closest to the lower end portion in FIG. 2 of the shaft 13 in the bracket 23, and extends in the lateral direction in FIG. The second bottom portion 23b extends in the axial direction between the outer diameter side end portion of the first bottom portion 23a and the inner diameter side end portion of the third bottom portion 23c. The third bottom portion 23c extends in the horizontal direction in FIG. 2 between the lower end portion of the cylindrical portion 23d and the upper end portion of the second bottom portion 23b. The folded portion 23e is formed by folding the upper end portion in FIG. 2 of the cylindrical portion 23d to the outer diameter side. The folded portion 23e extends downward in FIG. 2 from the boundary with the cylindrical portion 23d. The outer edge portion 23f extends from the outer diameter side end of the folded portion 23e to a position closer to the outer diameter side than the outer diameter side end of the stator core 21. The cylindrical portion 23d is a bearing housing portion, and the folded portion 23e is a core fixing portion.

  A bearing 30 is fixed to the inner peripheral surface of the cylindrical portion 23d. The bearing 30 has a cylindrical shape and extends along the shaft 13. The outer peripheral surface of the bearing 30 is in contact with the inner peripheral surface of the cylindrical portion 23d.

  The stator core 21 is fixed to the outer peripheral surface of the folded portion 23e. The stator core 21 includes a hole 61 formed at an inner diameter side end portion thereof, and an inner peripheral surface of the hole 61 is in contact with an outer peripheral surface of the folded portion 23e.

  The thrust plate 25 is circular, for example, and includes a contact surface that contacts the lower end of the shaft 13 in FIG. The thrust plate 25 receives a load in the thrust direction of the shaft 13. The first bottom portion 23 a comes into contact with the thrust plate 25 on the surface opposite to the contact surface with the shaft 13 in the thrust plate 25. The second bottom 23 b surrounds the outer periphery of the thrust plate 25.

  The motor 100 further includes an alignment member 41 and a cushion rubber 42. The turntable portion 11a has an inner diameter side end portion 11c bent upward in FIG. The alignment member 41 is fixed to the outer peripheral surface of the inner diameter side end portion 11c. A spring (not shown) is provided between the alignment member 41 and the inner diameter side end portion 11c, and the alignment member 41 is biased in the outer diameter direction. The cushion rubber 42 is disposed on the upper surface of the turntable portion 11a in FIG. When the disk 80 is set in the disk drive device, the disk 80 is disposed on the cushion rubber 42 so that the hole 80 a at the center thereof is fitted into the alignment member 41. The alignment member 41 fixes the disk 80 by pressing the inner peripheral surface of the hole 80a of the disk 80 by the action of a spring. The cushion rubber 42 suppresses the vibration of the disk 80 in the vertical direction in FIG.

  Next, an example of a method for manufacturing the disk rotation motor in the present embodiment will be described with reference to FIGS.

  Referring to FIG. 5, first, bracket 23 is manufactured by performing plastic working such as press working on one metal flat plate, for example. Subsequently, the stator core 21 is press-fitted and fixed to the bracket 23 by fitting the folded portion 23e into the hole 61 of the stator core 21 as indicated by an arrow A1.

  With reference to FIG. 6, subsequently, as indicated by an arrow A <b> 2, the bearing 30 is press-fitted and fixed to the bracket 23 by fitting the bearing 30 into the cylindrical portion 23 d of the bracket 23.

  Referring to FIG. 2, subsequently, attraction magnet 44 (FIG. 7) is mounted at a predetermined position as necessary. Next, the rotor 10 is mounted on the stator 20 by inserting the shaft 13 into the bearing 30. Thereafter, the alignment member 41 and the cushion rubber 42 are installed on the rotor frame 11, and the motor 100 is completed.

  According to the present embodiment, the bracket 23 including the cylindrical portion 23d that fixes the bearing 30 and the folded portion 23e that fixes the stator core is produced by bending a single plate. And the number of assembly steps can be reduced. As a result, the motor 100 can be manufactured by a simple method, and the cost of the motor can be reduced.

  Moreover, since the 1st-3rd bottom parts 23a-23c which support the lower end part in FIG. 2 of the shaft 13 are produced by bending one board with the cylindrical part 23d and the folding | turning part 23e, The number of parts can be reduced, and the number of assembly processes can be reduced. As a result, the motor 100 can be manufactured by a simple method, and the cost of the motor can be reduced.

  Further, the bracket 23 includes a first bottom portion 23 a that contacts the thrust plate 25, and a second bottom portion 23 b that is formed by bending the first bottom portion 23 a and surrounds the outer periphery of the thrust plate 25. The position of the thrust plate 25 can be regulated by the bracket 23.

  [Second Embodiment]

  7 and 8 are diagrams schematically showing the configuration of the disk rotation motor in the second embodiment of the present invention. 7 is a cross-sectional view, and FIG. 8 is a cross-sectional perspective view.

  With reference to FIGS. 7 and 8, the present embodiment is different from the first embodiment in that motor 100 further includes an attraction magnet 44. The attraction magnet 44 plays a role of stabilizing the position of the rotor 10 in the axial direction by magnetically attracting the rotor 10 (here, the rotor frame 11). The attraction magnet 44 is fitted into the outer peripheral surface of the bearing 30 on the boundary between the cylindrical portion 23d and the folded portion 23e (on the folded position). The attraction magnet 44 is fixed to the outer peripheral surface of the bearing 30 so as to be in contact with the boundary between the cylindrical portion 23d and the folded portion 23e.

  Since the configuration of motor 100 other than that described above is the same as the configuration of the motor in the first embodiment, description thereof will not be repeated individually.

  According to the present embodiment, the position of the attracting magnet 44 can be regulated by the boundary between the cylindrical portion 23d and the folded portion 23e. Thereby, the attractive force of the attractive magnet 44 against the rotor 10 becomes uniform.

  [Third Embodiment]

  9 and 10 are diagrams schematically showing a configuration of a disk rotation motor in the third embodiment of the present invention. 9 is a sectional view, and FIG. 10 is a sectional perspective view. In FIG. 9, only a part of the configuration of the disk rotation motor is shown.

  With reference to FIG. 9 and FIG. 10, the present embodiment is different from the second embodiment in the position of the attracting magnet 44. The attraction magnet 44 is fitted on the outer peripheral surface of the folded portion 23 e on the stator core 21. The attraction magnet 44 is fixed to the outer peripheral surface of the folded portion 23 e so as to come into contact with the stator core 21.

  Since the configuration of the motor 100 other than the above is the same as the configuration of the motor in the second embodiment, the description thereof will not be repeated individually.

  According to the present embodiment, the position of the attracting magnet 44 can be regulated by the stator core 21. Thereby, the attractive force of the attractive magnet 44 against the rotor 10 becomes uniform.

  [Fourth Embodiment]

  FIG. 11 is a cross-sectional view schematically showing the configuration of a disk rotation motor in the fourth embodiment of the invention.

  Referring to FIG. 11, bracket 23 is different from the second embodiment in that bracket 23 further includes a separating portion 23g at the boundary between cylindrical portion 23d and folded portion 23e. The separating portion 23g extends in the radial direction (lateral direction in FIG. 11) from the upper end portion in FIG. 11 of the cylindrical portion 23d toward the upper end portion in FIG. 11 of the folded portion 23e. The separating part 23g separates the cylindrical part 23d and the folded part 23e from each other, and there is a gap d between the cylindrical part 23d and the folded part 23e.

  Since the configuration of the motor 100 other than the above is the same as the configuration of the motor in the second embodiment, the description thereof will not be repeated individually.

  According to the present embodiment, the radial position of the folded portion 23e can be adjusted by the radial length of the separation portion 23g. Thereby, the stator core 21 of various sizes can be attached to the bracket 23.

  [Others]

  The disk rotation motor of the present invention may be a shaft fixed type motor, a plane facing type motor, or the like in addition to the shaft rotation type motor as in the above embodiment.

  The above-described embodiments can be combined as appropriate. For example, when the configuration of FIG. 9 and the configuration of FIG. 11 are combined and the bracket 23 has a shape including the separation portion 23g, the attractive magnet 44 is fitted on the outer peripheral surface of the folded portion 23e on the stator core 21. Also good.

  The above-described embodiment is to be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

DESCRIPTION OF SYMBOLS 10 Rotor 11 Rotor frame 11a Turn table part of rotor frame 11b Side wall part of rotor frame 11c Inner diameter side end part of rotor frame 12 Magnet 13 Shaft 13a Groove part of shaft 14 Washer 20 Stator 21 Stator core 21a Teeth part 22 Stator coil 23 Bracket 23a, 23b, 23c Bracket bottom portion 23d Bracket cylindrical portion 23e Bracket folding portion 23f Bracket outer edge portion 23g Bracket separation portion 24 Bottom plate 25 Thrust plate 30 Bearing 41 Alignment member 42 Cushion rubber 44 Suction magnet 60, 61 Hole 80 Disc 80a disc hole 100 motor 200 control unit d gap

Claims (8)

A stator including a stator core and a bracket for fixing the stator core;
A rotor that is rotatable relative to the stator and includes a rotational axis;
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 rotation axis, a folded portion formed in a state where an upper end portion of the cylindrical portion is folded back to an outer diameter side, and a lower end portion of the folded portion. Including an outer edge formed in a state of being folded back to the radial side,
The bearing is fixed in contact with the inner peripheral surface of the cylindrical portion, and the stator core is fixed to the outer peripheral surface of the folded portion,
The folding position between the folded portion and the outer edge portion is present below the lower end portion of the stator core with a gap from the lower end portion of the stator core,
The disk turning motor, wherein the turning portion has a uniform diameter from a turning position with the tubular portion to a turning position with the outer edge portion. The bracket further includes a bottom portion formed in a state where an end portion of the cylindrical portion is bent toward an inner diameter side,
The disk rotating motor according to claim 1, wherein the bottom portion supports one end portion of the rotating shaft. A thrust plate having a contact surface in contact with one end of the rotating shaft;
The bottom portion is formed with a first bottom portion that contacts the thrust plate on a surface opposite to the contact surface, a second bottom portion that is bent, and surrounds an outer periphery of the thrust plate. The disk rotating motor according to claim 2, including a bottom portion of the disk.   The disk rotation motor according to claim 1, further comprising an attraction magnet that magnetically attracts the rotor.   The disk rotation motor according to claim 4, wherein the attraction magnet is fixed to an outer peripheral surface of the bearing so as to come into contact with a boundary between the cylindrical portion and the folded portion.   The disk rotation motor according to claim 4, wherein the attraction magnet is fixed to an outer peripheral surface of the folded portion so as to be in contact with the stator core.   The disk rotation motor according to claim 1, wherein the stator core and the bearing are opposed to each other in a radial direction across the cylindrical portion and the turned-up portion.   A disk drive device comprising: the disk rotation motor according to claim 1; and a control unit that controls a drive state of the disk rotation motor.

Images