Disk device

Abstract

To provide a disk device that can be easily manufactured.SOLUTION: A disk device according to an embodiment includes a plurality of magnetic disks, a plurality of arms, a suspension, and a first damper. The plurality of disks are arranged along a first axis of rotation. The arms are arranged along a second axis of rotation. The arm includes a first side surface, a second side surface having a slit, a first surface facing the first magnetic disk, a second surface facing the second magnetic disk, a first seat surface, and a second seat surface. The arm is provided with a first recess that opens to the first side surface and the first surface and is closer to the first axis of rotation than the slit. The suspension is supported on the first seat surface or the second seat surface and is partially accommodated in the slit. The first damper is arranged on the first recess and is attached to the first arm.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a disk device. [Background technology]

[0002] A disk device such as a hard disk drive (HDD) has, for example, a magnetic disk, a magnetic head that reads and writes information from and to the magnetic disk, a suspension that supports the magnetic head, and a carriage that moves the magnetic head and the suspension. In addition, the disk device may have a damper that attenuates vibrations of an arm of the carriage. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] U.S. Patent No. 7,522,385 Summary of the Invention [Problem to be solved by the invention]

[0004] The damper is attached to the surface of the arm, for example. A gap is provided between the damper and the magnetic disk, which prevents the damper from coming into contact with the magnetic disk due to vibration, for example. However, providing a large gap between the damper and the magnetic disk can make it difficult to manufacture the disk device.

[0005] One example of a problem to be solved by the present invention is to provide a disk device that can be easily manufactured. [Means for solving the problem]

[0006] A disk device according to one embodiment includes a plurality of magnetic disks, a plurality of arms, a plurality of suspensions, and a plurality of first dampers. The plurality of disks are arranged along a first rotation axis and are rotatable about the first rotation axis. The plurality of arms are arranged along a second rotation axis spaced apart from the first rotation axis and are each capable of entering a gap between two adjacent magnetic disks among the plurality of magnetic disks by rotating about the second rotation axis. Each of the arms has a first side surface facing the first rotation axis, a second side surface located on the opposite side of the first side surface and having a slit, a first surface facing a first magnetic disk that is one of the two magnetic disks, a second surface facing a second magnetic disk that is the other of the two magnetic disks, a first seating surface facing the first magnetic disk, being farther away from the first magnetic disk than the first surface and being farther away from the second rotation axis than the first surface, and a second seating surface facing the second magnetic disk, being farther away from the second magnetic disk than the second surface and being farther away from the second rotation axis than the second surface. Each of the arms is provided with a first recess that opens to the first side surface and the first surface and is closer to the first rotation axis than the slit in a direction perpendicular to the first rotation axis. The suspensions are supported by the first seating surface or the second seating surface, partially housed in the slits, and attached to the arms. The first dampers are disposed in the first recesses, attached to the arms, and configured to damp vibrations of the arms. [Brief description of the drawings]

[0007] [Figure 1] FIG. 1 is an exemplary exploded perspective view of a HDD according to the first embodiment. [Diagram 2] FIG. 2 is an exemplary plan view partially illustrating the HGA and the arm of the first embodiment. [Diagram 3] FIG. 3 is an exemplary cross-sectional view showing a portion of the HDD of the first embodiment. [Figure 4] FIG. 4 is an exemplary cross-sectional view showing the HSA of the first embodiment taken along line F4-F4 in FIG. [Diagram 5] FIG. 5 is an exemplary cross-sectional view showing the carriage and gang cutter of the first embodiment. [Figure 6] FIG. 6 is an exemplary plan view showing the carriage and gang cutter of the first embodiment. [Figure 7] FIG. 7 is an exemplary cross-sectional view showing an HSA according to the second embodiment. [Figure 8] FIG. 8 is an exemplary cross-sectional view showing a carriage and a gang cutter of the second embodiment. [Figure 9] FIG. 9 is an exemplary cross-sectional view showing a portion of an HSA according to the third embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] (First embodiment) The first embodiment will be described below with reference to FIGS. 1 to 6. In this specification, components according to the embodiment and their descriptions may be described in a number of ways. The components and their descriptions are merely examples and are not limited by the expressions in this specification. The components may be identified by names different from those in this specification. The components may also be described by expressions different from those in this specification.

[0009] In the following description, "suppress" is defined as, for example, preventing the occurrence of an event, action, or influence, or reducing the severity of an event, action, or influence. Also, in the following description, "restrict" is defined as, for example, preventing movement or rotation, or allowing movement or rotation within a predetermined range and preventing movement or rotation beyond the predetermined range.

[0010] 1 is an exemplary exploded perspective view showing a hard disk drive (HDD) 10 according to the first embodiment. The HDD 10 is an example of a disk device, and may also be called an electronic device, a storage device, an external storage device, or a magnetic disk device.

[0011] 1, the HDD 10 includes a housing 11, a plurality of magnetic disks 12, a spindle motor 13, a head stack assembly (HSA) 14, a voice coil motor (VCM) 15, a ramp load mechanism 16, and a printed circuit board (PCB) 17. The magnetic disks 12 may also be called disks or platters.

[0012] 1, for the sake of convenience, a Z axis and a Z direction are defined in this specification. The Z axis is provided along the thickness of the HDD 10. The Z direction is a direction along the Z axis, and includes a +Z direction indicated by the Z axis arrow and a -Z direction opposite to the Z axis arrow.

[0013] The housing 11 has a base 21, an inner cover 22, and an outer cover 23. The housing 11 is not limited to this example. The base 21, the inner cover 22, and the outer cover 23 are each made of a metal material such as an aluminum alloy. The materials of the base 21, the inner cover 22, and the outer cover 23 may be different from each other.

[0014] The base 21 is formed in a substantially rectangular box shape that is open in the +Z direction. The base 21 houses a plurality of magnetic disks 12, a spindle motor 13, an HSA 14, a VCM 15, and a ramp load mechanism 16.

[0015] The base 21 has a bottom wall 25 and side walls 26. The bottom wall 25 is formed in a substantially rectangular (quadrilateral) plate shape arranged substantially perpendicular to the Z direction. The side walls 26 protrude from the edge of the bottom wall 25 in substantially the +Z direction and are formed in a substantially rectangular frame shape.

[0016] The inner cover 22 is attached to the end of the side wall 26 in the +Z direction by, for example, screws, and closes the base 21. The outer cover 23 covers the inner cover 22, and is attached to the end of the side wall 26 in the +Z direction by, for example, welding.

[0017] An air vent 27 is provided in the inner cover 22. Furthermore, an air vent 28 is provided in the outer cover 23. After components are attached inside the base 21 and the inner cover 22 and the outer cover 23 are attached to the base 21, air inside the housing 11 is evacuated through the air vents 27, 28. Furthermore, the inside of the housing 11 is filled with a gas other than air.

[0018] The gas filled inside the housing 11 is, for example, a low-density gas having a density lower than air, an inert gas having a low reactivity, or the like. For example, helium is filled inside the housing 11. Note that other fluids may be filled inside the housing 11. Furthermore, the inside of the housing 11 may be kept at a vacuum, a low pressure close to a vacuum, or a negative pressure lower than atmospheric pressure.

[0019] The vent hole 28 of the outer cover 23 is closed by a seal 29. The seal 29 air-tightly seals the vent hole 28 and restricts the fluid filled inside the housing 11 from leaking from the vent hole 28 to the outside of the housing 11.

[0020] The multiple magnetic disks 12 are formed in a disk shape and arranged so as to be approximately perpendicular to the Z direction. The multiple magnetic disks 12 are arranged along the central axis Axd of the magnetic disks 12 with gaps between them. The central axis Axd is an example of a first rotation axis. The central axis Axd is a virtual axis that extends approximately in the Z direction.

[0021] Each of the multiple magnetic disks 12 has, for example, at least one recording surface 12a. Each of the multiple recording surfaces 12a is a surface of the magnetic disk 12 facing approximately in the +Z direction or a surface of the magnetic disk 12 facing approximately in the -Z direction. The recording surface 12a is a substantially flat surface that is substantially perpendicular to the Z direction. A magnetic recording layer of the magnetic disk 12 is provided on the recording surface 12a.

[0022] The spindle motor 13 supports the multiple magnetic disks 12 and rotates them about a central axis Axd. The central axis Axd is also the central axis of the spindle motor 13. The multiple magnetic disks 12 are held on a hub of the spindle motor 13 by, for example, a clamp spring.

[0023] A support shaft 31 is provided in the housing 11, spaced apart from the magnetic disk 12 in a direction perpendicular to the central axis Axd. The support shaft 31 extends, for example, from the bottom wall 25 of the housing 11 in approximately the +Z direction. The HSA 14 is rotatably supported by the support shaft 31.

[0024] The HSA 14 can rotate around a central axis Axh. The central axis Axh is an example of a second rotation axis, and is a virtual axis extending substantially in the Z direction. The central axis Axh is, for example, the center of rotation of the HSA 14, and is also the central axis of the support shaft 31. For this reason, the central axis Axh is spaced from the central axis Axd of the magnetic disk 12 in a direction perpendicular to the central axis Axd.

[0025] The HSA 14 has a carriage 35, a plurality of head gimbal assemblies (HGA) 36, and a flexible printed circuit board (FPC) 37. The carriage 35 has an actuator block 41, a plurality of arms 42, and a coil holder 43.

[0026] The actuator block 41, the arms 42, and the coil holder 43 are integrally formed from, for example, an aluminum alloy. Note that the materials of the actuator block 41, the arms 42, and the coil holder 43 are not limited to this example.

[0027] The actuator block 41 is supported by the support shaft 31 via a bearing so as to be rotatable about the central axis Axh, for example. This allows the carriage 35 to rotate about the central axis Axh.

[0028] The arms 42 protrude from the actuator block 41 in a direction substantially perpendicular to the central axis Axh. Note that the HSA 14 may be divided so that the arms 42 protrude from each of the actuator blocks 41.

[0029] 2 is an exemplary plan view partially showing the HGA 36 and the arm 42 of the first embodiment. As shown in FIG. 2, for convenience, an X-axis and a Y-axis are further defined in this specification. The X-axis, the Y-axis, and the Z-axis are mutually orthogonal. The Y-axis is provided along the arm 42. Furthermore, an X-direction and a Y-direction are further defined in this specification. The X-direction is a direction along the X-axis, and includes a +X-direction indicated by an arrow of the X-axis, and a -X-direction that is the opposite direction of the arrow of the X-axis. The Y-direction is a direction along the Y-axis, and includes a +Y-direction indicated by an arrow of the Y-axis, and a -Y-direction that is the opposite direction of the arrow of the Y-axis.

[0030] The arms 42 protrude from the actuator block 41 in the +Y direction. Therefore, the Y direction is the longitudinal direction of the arms 42. The X direction is the lateral direction of the arms 42. The X and Y directions change as the carriage 35 rotates around the central axis Axh. The central axis Axd of the magnetic disk 12 is spaced apart from the arms 42 in approximately the -X direction.

[0031] The actuator block 41 has multiple side surfaces 41a, 41b, and 41c. The side surface 41a faces approximately in the +Y direction. The side surface 41b faces approximately in the -X direction. The side surface 41c extends obliquely with respect to the X and Y directions between the side surfaces 41a and 41b. The multiple arms 42 protrude in the +Y direction from the side surfaces 41a and 41c of the actuator block 41.

[0032] The side surface 41c extends obliquely with respect to the X direction and the Y direction, thereby forming a notch 45 in the actuator block 41. The provision of the notch 45 can prevent the actuator block 41 from coming into contact with the magnetic disk 12 when the actuator block 41 rotates about the central axis Axh.

[0033] The arms 42 are arranged in the Z direction along the central axis Axh with gaps between them. The arms 42 extend substantially parallel to each other. The arms 42 are formed in the shape of a plate arranged substantially perpendicular to the Z direction. That is, the magnetic disks 12 and the arms 42 are arranged substantially parallel to each other.

[0034] By rotating the carriage 35 including the arms 42 in one direction about the central axis Axh, each of the multiple arms 42 can enter a gap between two adjacent magnetic disks 12 among the multiple magnetic disks 12. By rotating the carriage 35 in the other direction about the central axis Axh, each of the multiple arms 42 can exit from the gap between the two adjacent magnetic disks 12.

[0035] 3 is an exemplary cross-sectional view showing a portion of the HDD 10 of the first embodiment. As shown in FIG. 3, when each of the multiple arms 42 is described, two adjacent ones of the multiple magnetic disks 12 are referred to as magnetic disks 12U and 12L. The magnetic disk 12U is an example of a magnetic disk and a first magnetic disk. The magnetic disk 12L is an example of a second magnetic disk.

[0036] The described one arm 42 enters between the two magnetic disks 12U, 12L as a result of the carriage 35 including the arm 42 rotating about the central axis Axh. The magnetic disk 12U is spaced apart from the arm 42 in the +Z direction. The magnetic disk 12L is spaced apart from the arm 42 in the -Z direction.

[0037] Each of the multiple magnetic disks 12 can be a magnetic disk 12U for one of the arms 42, and can be a magnetic disk 12L for the other arm 42. For the sake of explanation, Fig. 3 shows one of the multiple magnetic disks 12 as a magnetic disk 12U, and the other of the multiple magnetic disks 12 as a magnetic disk 12L.

[0038] 1 protrudes in the -Y direction from the actuator block 41. The coil holder 43 holds the voice coil of the VCM 15. The VCM 15 has the voice coil, a pair of yokes, and a magnet provided in the yokes.

[0039] Each of the arms 42 has a first side surface 42a, a second side surface 42b, a first surface 42c, and a first seating surface 42d shown in Fig. 2, and a second surface 42e and a second seating surface 42f shown in Fig. 3. The first seating surface 42d is an example of a seating surface.

[0040] 2 faces approximately in the -X direction. That is, the first side surface 42a faces the central axis Axd. Note that the first side surface 42a may temporarily not face the central axis Axd by rotating the carriage 35 around the central axis Axh.

[0041] The second side 42b is located opposite the first side 42a. The second side 42b faces approximately in the +X direction. The first side 42a and the second side 42b approach each other toward the end of the arm 42 in the +Y direction. That is, between the first side 42a and the second side 42b, the arm 42 tapers in the +Y direction.

[0042] The first side surface 42a is continuous with the side surface 41b of the actuator block 41. Note that the first side surface 42a is not limited to this example. Since the actuator block 41 has the notch 45, the first side surface 42a is longer than the second side surface 42b.

[0043] The first surface 42c and the first seating surface 42d are formed substantially flat and face substantially in the +Z direction. The first surface 42c and the first seating surface 42d face the magnetic disk 12U. Note that the first surface 42c and the first seating surface 42d may temporarily not face the magnetic disk 12U by rotating the carriage 35 around the central axis Axh.

[0044] The first bearing surface 42d is provided at an end of the arm 42 in the +Y direction. Therefore, the first bearing surface 42d is farther away from the central axis Axh than the first surface 42c. Also, the first bearing surface 42d is farther away from the magnetic disk 12U than the first surface 42c.

[0045] 3, the second surface 42e is located on the opposite side to the first surface 42c. The second seating surface 42f is located on the opposite side to the first seating surface 42d. The second surface 42e and the second seating surface 42f are formed substantially flat and face substantially in the -Z direction.

[0046] The second surface 42e and the second seating surface 42f face the magnetic disk 12L. Note that the second surface 42e and the second seating surface 42f may temporarily not face the magnetic disk 12L by rotating the carriage 35 about the central axis Axh.

[0047] The second seating surface 42f is provided at an end of the arm 42 in the +Y direction. Therefore, the second seating surface 42f is farther away from the central axis Axh than the second surface 42e. Also, the second seating surface 42f is farther away from the magnetic disk 12L than the second surface 42e.

[0048] Each of the arms 42 is provided with a slit 51, a through hole 52, and a first recess 53 shown in Fig. 2, and a second recess 54 shown in Fig. 3. The first recess 53 and the second recess 54 may also be referred to as a step or a notch. Note that the arm 42 may omit the second recess 54.

[0049] 2, the slit 51 is provided on the second side surface 42b. The slit 51 is spaced apart from the first surface 42c and the second surface 42e, and extends in a substantially linear manner between both ends of the second side surface 42b in the Y direction.

[0050] The through hole 52 penetrates the arm 42 in the +Z direction so as to open to the first seating surface 42d and the second seating surface 42f. The through hole 52 is a substantially circular hole. Note that the shape of the through hole 52 is not limited to this example. The through hole 52 is farther away from the central axis Axh than the slit 51.

[0051] The first recess 53 is provided in the first surface 42c and expands to reach the first side surface 42a. Therefore, the first recess 53 opens to the first side surface 42a and the first surface 42c. The entire first recess 53 is closer to the central axis Axd than the slit 51 in a direction perpendicular to the central axis Axd. In addition, the first recess 53 is spaced apart from the first seat surface 42d and the actuator block 41.

[0052] The second recess 54 is provided in the second surface 42e and expands to reach the first side surface 42a. Therefore, the second recess 54 opens to the first side surface 42a and the second surface 42e. The entire second recess 54 is closer to the central axis Axd than the slit 51 in a direction perpendicular to the central axis Axd. In addition, the second recess 54 is spaced apart from the second seat surface 42f and the actuator block 41.

[0053] The arm 42 further has a bottom surface 53a of the first recess 53 and a bottom surface 54a of the second recess 54. The bottom surface 53a is an example of a mounting surface. The bottom surface 53a is provided at the bottom of the first recess 53 in the Z direction. Therefore, the first seating surface 42d is farther away from the central axis Axh than the bottom surface 53a. The bottom surface 54a is provided at the bottom of the second recess 54 in the Z direction. Therefore, the second seating surface 42f is farther away from the central axis Axh than the bottom surface 54a.

[0054] The bottom surface 53a is formed to be substantially flat and faces substantially in the +Z direction. The bottom surface 53a faces the magnetic disk 12U. In the Z direction, the bottom surface 53a is farther away from the magnetic disk 12U than the first surface 42c. Furthermore, in the Z direction, the bottom surface 53a is farther away from the magnetic disk 12U than the first seating surface 42d. Therefore, in the Z direction along the central axis Axh, the depth of the first recess 53 is greater than the distance between the first surface 42c and the first seating surface 42d.

[0055] The bottom surface 54a is formed to be substantially flat and faces substantially in the -Z direction. The bottom surface 54a faces the magnetic disk 12L. In the Z direction, the bottom surface 54a is farther away from the magnetic disk 12L than the second surface 42e. Furthermore, in the Z direction, the bottom surface 54a is farther away from the magnetic disk 12L than the second seating surface 42f. Therefore, in the Z direction along the central axis Axh, the depth of the second recess 54 is greater than the distance between the second surface 42e and the second seating surface 42f.

[0056] An edge 53b of the first recess 53 on the first surface 42c and an edge 54b of the second recess 54 on the second surface 42e are mirror symmetrical to each other. In the Z direction along the central axis Axh, the depth of the first recess 53 is approximately equal to the depth of the second recess 54. Therefore, the first recess 53 and the second recess 54 in the first embodiment are mirror symmetrical to each other.

[0057] Each of the first depression 53 and the second depression 54 is not symmetrical with respect to the center line L in a projection view seen in the Z direction along the central axis Axh as in Figure 2. The center line L is an imaginary straight line extending between the central axis Axh and the center of the through hole 52.

[0058] In this embodiment, the first recess 53 and the second recess 54 taper from the first side surface 42a to the second side surface 42b. That is, the width of the first recess 53 on the first side surface 42a is greater than the width of the end of the first recess 53 that is farthest from the first side surface 42a.

[0059] The first recess 53 and the second recess 54 are partially disposed in the cutout 45 of the actuator block 41. In other words, in the Y direction, the first recess 53 and parts of the second recess 54 are closer to the central axis Axh than the side surface 41a of the actuator block 41.

[0060] Each of the multiple HGAs 36 is attached to the first seating surface 42d or the second seating surface 42f so as to protrude from the arm 42 in approximately the +Y direction. As a result, the multiple HGAs 36 are arranged with gaps between them in the Z direction along the central axis Axh. The HGAs 36 attached to the first seating surface 42d are formed approximately mirror symmetrically with respect to the HGAs 36 attached to the second seating surface 42f.

[0061] Each of the multiple HGAs 36 has a magnetic head 61 and a suspension 62. That is, the HDD 10 has multiple magnetic heads 61 and multiple suspensions 62. The magnetic heads 61 may also be referred to as sliders.

[0062] The magnetic head 61 records and reproduces information on a corresponding one of the recording surfaces 12a of the multiple magnetic disks 12. In other words, the magnetic head 61 reads and writes information from and to the magnetic disk 12.

[0063] The suspension 62 is attached to the arm 42 and holds the magnetic head 61. The suspension 62 has a base plate 65, a load beam 66, and a flexure 67.

[0064] The base plate 65 and the load beam 66 are made of, for example, stainless steel (SUS). However, the materials of the base plate 65 and the load beam 66 are not limited to this example. The base plate 65 and the load beam 66 may be made of different materials.

[0065] The base plate 65 has a plate 71 and a boss 72. The plate 71 is formed in a substantially rectangular plate shape arranged substantially perpendicular to the Z direction. The plate 71 is supported by the first seating surface 42d or the second seating surface 42f.

[0066] The boss 72 protrudes from the plate 71. The boss 72 is formed in a substantially cylindrical shape, and is fitted into the through hole 52 of the arm 42. The boss 72 is swaged to the arm 42. That is, the suspension 62 is attached to the arm 42 by being partially fitted into the through hole 52. Note that the suspension 62 may be attached to the arm 42 by other methods.

[0067] The load beam 66 is formed in a plate shape that is thinner than the base plate 65. The load beam 66 is fixed to the plate 71 by, for example, spot welding. The load beam 66 extends from the plate 71 approximately in the +Y direction.

[0068] The flexure 67 is a type of flexible printed wiring board formed in a long and narrow strip shape. The flexure 67 has, for example, a gimbal portion 75 and a suspension tail 76.

[0069] The gimbal portion 75 is provided at an end of the flexure 67 in the +Y direction. The gimbal portion 75 is supported by the load beam 66 so as to be elastically rotatable, and has the magnetic head 61 attached thereto. The suspension tail 76 extends from the gimbal portion 75 toward the actuator block 41. Note that other portions may be provided between the gimbal portion 75 and the suspension tail 76. The suspension tail 76 is partially housed in the slit 51.

[0070] An end of the suspension tail 76 in the -Y direction is connected to one end of the FPC 37 attached to the actuator block 41. In other words, a part of the suspension tail 76 extends between the gimbal portion 75 and the FPC 37 through the slit 51. The other end of the FPC 37 is connected to a connector provided on the bottom wall 25, for example.

[0071] The carriage 35 rotates about the central axis Axh to move the magnetic head 61 relative to the corresponding magnetic disk 12. The VCM 15 rotates the carriage 35 about the central axis Axh to move the magnetic head 61 to a desired position along the recording surface 12a of the magnetic disk 12.

[0072] When the magnetic head 61 moves to the outer edge of the magnetic disk 12 due to the rotation of the HSA 14 by the VCM 15 , the ramp load mechanism 16 in FIG.

[0073] 1 is, for example, a rigid board such as a glass epoxy board, and is a multi-layer board or a build-up board, etc. The PCB 17 is disposed outside the housing 11 and attached to the bottom wall 25.

[0074] Various electronic components are mounted on the PCB 17, such as a relay connector electrically connected to the FPC 37, an interface (I / F) connector connected to a host computer, and a controller that controls the operation of the HDD 10. The relay connector is electrically connected to the FPC 37 via a connector provided on the bottom wall 25.

[0075] The controller of the PCB 17 drives the VCM 15 to rotate the HSA 14 around the central axis Axh. In this way, the controller controls the position of the magnetic head 61. The controller may adjust the position of the magnetic head 61 by a piezoelectric element provided in the HGA 36.

[0076] Fig. 4 is an exemplary cross-sectional view showing the HSA 14 of the first embodiment taken along line F4-F4 in Fig. 2. As shown in Fig. 4, the HSA 14 further has a plurality of first dampers 81 and a plurality of second dampers 82. The first damper 81 is an example of a damper. One first damper 81 and one second damper 82 are attached to one arm 42.

[0077] Each of the multiple first dampers 81 has a constrained layer 85 and a viscoelastic material (VEM) 86. It should be noted that the first dampers 81 are not limited to this example.

[0078] The constraining layer 85 is formed in a plate shape arranged approximately perpendicular to the Z direction. The constraining layer 85 is made of, for example, stainless steel. Therefore, the density (mass per unit volume) of the constraining layer 85 is approximately three times the density of the arm 42. In other words, the constraining layer 85 has a higher density than the arm 42. Note that the material of the constraining layer 85 is not limited to this example.

[0079] The viscoelastic body 86 has a lower rigidity than the constraining layer 85. The viscoelastic body 86 is located between the constraining layer 85 and the bottom surface 53a of the first recess 53, and is attached to the constraining layer 85 and the bottom surface 53a. That is, the viscoelastic body 86 is interposed between the constraining layer 85 and the bottom surface 53a of the arm 42. As a result, the first damper 81 is disposed in the first recess 53, and attached to the bottom surface 53a of the arm 42.

[0080] 2, in a projection view seen in the Z direction along the central axis Axh, the shape of the first damper 81 is substantially equal to the shape of the first recess 53, but is smaller than the first recess 53. For this reason, the first damper 81 is not axisymmetric with respect to the center line L in a projection view seen in the Z direction along the central axis Axh.

[0081] 4, in the Z direction along the central axis Axh, the thickness of the first damper 81 is smaller than the depth of the first recess 53. Therefore, the entire first damper 81 is accommodated in the first recess 53. Note that a part of the first damper 81 may be located outside the first recess 53.

[0082] For example, in the Z direction, the depth of the first recess 53 is three times the thickness of the constraining layer 85. Furthermore, the thickness of the viscoelastic body 86 is approximately equal to the thickness of the constraining layer 85. It should be noted that the thicknesses of the constraining layer 85 and the viscoelastic body 86 are not limited to this example.

[0083] The second damper 82 is provided substantially mirror-symmetrically with respect to the first damper 81. For example, each of the second dampers 82 has a constraining layer 87 and a viscoelastic body 88. The constraining layer 87 is formed in a plate shape arranged substantially perpendicular to the Z direction. The constraining layer 87 is made of, for example, stainless steel. Note that the material of the constraining layer 87 is not limited to this example.

[0084] The viscoelastic body 88 has a lower rigidity than the constraining layer 87. The viscoelastic body 88 is located between the constraining layer 87 and the bottom surface 54a of the second recess 54, and is attached to the constraining layer 87 and the bottom surface 54a. That is, the viscoelastic body 88 is interposed between the constraining layer 87 and the bottom surface 54a of the arm 42. As a result, the second damper 82 is disposed in the second recess 54, and attached to the bottom surface 54a of the arm 42.

[0085] In a projection view seen in the Z direction along the central axis Axh, the shape of the second damper 82 is substantially equal to the shape of the second recess 54, and is smaller than the second recess 54. For this reason, the second damper 82 is not axisymmetric with respect to the center line L in a projection view seen in the Z direction along the central axis Axh.

[0086] In the Z direction along the central axis Axh, the thickness of the second damper 82 is smaller than the depth of the second recess 54. Therefore, the entire second damper 82 is housed in the second recess 54. Note that a part of the second damper 82 may be located outside the second recess 54.

[0087] For example, in the Z direction, the depth of the second recess 54 is three times the thickness of the constraining layer 87. Furthermore, the thickness of the viscoelastic body 88 is approximately equal to the thickness of the constraining layer 87. It should be noted that the thicknesses of the constraining layer 87 and the viscoelastic body 88 are not limited to this example.

[0088] For example, the thickness of each of the constraint layers 85, 87 and the viscoelastic bodies 86, 88 is about 50 μm. The depth of the first recess 53 and the second recess 54 is about 150 μm. The thickness of the arm 42 between the first surface 42c and the second surface 42e is about 0.8 mm. The thickness of the arm 42 between the first seating surface 42d and the second seating surface 42f is about 0.6 mm. The thickness of the arm 42 between the bottom surface 53a and the bottom surface 54a is about 0.5 mm. Note that the above dimensions are not limited to this example.

[0089] When the arm 42 vibrates, the vibration of the arm 42 is transmitted to the first damper 81 and the second damper 82. As a result, the constraining layers 85, 87 vibrate relative to the arm 42. The viscoelastic bodies 86, 88 deform between the constraining layers 85, 87 and the arm 42, and convert the energy of the vibration into heat. As a result, the first damper 81 and the second damper 82 damp the vibration of the arm 42.

[0090] Since the vibration of the arm 42 is damped by the first damper 81 and the second damper 82, the HDD 10 can accurately position the magnetic head 61 even if the recording density is high. That is, the HDD 10 can improve the recording density.

[0091] The first damper 81 is disposed in the first recess 53, and the second damper 82 is disposed in the second recess 54. As a result, the total thickness of the arm 42, the first damper 81, and the second damper 82 is small in the portion where the first damper 81 and the second damper 82 are attached to the arm 42, and a sufficient distance is provided between the first damper 81 and the magnetic disk 12U. Also, a sufficient distance is provided between the second damper 82 and the magnetic disk 12L.

[0092] 5 and 6, a method for forming the first recess 53 and the second recess 54, which is part of a method for manufacturing the HDD 10, will be described below. Note that the method for forming the first recess 53 and the second recess 54 is not limited to the following method, and other methods may be used.

[0093] Fig. 5 is an exemplary cross-sectional view showing the carriage 35 and gang cutter 100 of the first embodiment. Fig. 6 is an exemplary plan view showing the carriage 35 and gang cutter 100 of the first embodiment.

[0094] 5 and 6, for example, a gang cutter 100 forms a first recess 53 and a second recess 54 in the arm 42. The gang cutter 100 has a plurality of blades 101. The blades 101 are formed in a substantially disk shape.

[0095] 5, the blades 101 are arranged with gaps between them along the central axis Axg of the blades 101. The blades 101 rotate together around the central axis Axg. In this embodiment, the central axis Axg extends substantially in the Z direction.

[0096] The thickness of the blade 101 is greater than the distance between two adjacent ones of the multiple arms 42. In this embodiment, the center of the blade 101 in the Z direction is disposed in the middle between the two adjacent arms 42.

[0097] The blade 101 can contact two adjacent arms 42 simultaneously. Therefore, the blade 101 rotating around the central axis Axg cuts the two arms 42 simultaneously. In the Z direction, the sum of the depth of the first recess 53, the depth of the second recess 54, and the distance between the two adjacent arms 42 is approximately equal to the thickness of the blade 101.

[0098] The arrows in Fig. 6 indicate an example of a movement path of the central axis Axg relative to the arm 42 when the gang cutter 100 cuts the arm 42. As shown in Fig. 6, the blade 101 cuts the arm 42 from the first side surface 42a, thereby forming a first recess 53 in one of the two arms 42 and forming a second recess 54 in the other of the two arms 42. Since the blade 101 is disk-shaped, the first recess 53 and the second recess 54 taper from the first side surface 42a toward the second side surface 42b.

[0099] The distance between the first side surface 42a and the slit 51 in the X direction is smaller than the radius of the blade 101. Therefore, the blade 101 can form a first depression 53 and a second depression 54 that extend from the first side surface 42a to the vicinity of the slit 51. Note that the distance between the first side surface 42a and the slit 51 may be larger than the radius of the blade 101.

[0100] For example, when one blade 101 forms a first recess 53 in one arm 42, it pushes the one arm 42 in approximately the -Z direction. In other words, a force acts from the one blade 101 to the one arm 42 so as to bend the one arm 42. However, when the other blade 101 forms a second recess 54 in the one arm 42, it pushes the one arm 42 in approximately the +Z direction. In other words, the two blades 101 support the one arm 42 from both sides, thereby restricting the one arm 42 from bending elastically.

[0101] The first bearing surface 42d and the second bearing surface 42f of the arm 42 can be formed by the gang cutter 100, similar to the first recess 53 and the second recess 54. For example, the gang cutter 100 can cut the arm 42 with a blade having a different thickness from the blade 101 to form the first bearing surface 42d and the second bearing surface 42f.

[0102] In the Z direction, the thickness of the arm 42 between the first seating surface 42d and the second seating surface 42f is set to be larger than the total thickness of the two bosses 72 fitted into the through-holes 52. This prevents the two bosses 72 from interfering with each other. However, the thickness of the arm 42 between the first seating surface 42d and the second seating surface 42f is subject to design constraints.

[0103] On the other hand, the thickness of the arm 42 between the bottom surface 53a of the first recess 53 and the bottom surface 54a of the second recess 54 is unlikely to affect the interference between the two bosses 72 in the through hole 52. For this reason, the depths of the first recess 53 and the second recess 54 are less restricted in design than the thickness of the arm 42 between the first seating surface 42d and the second seating surface 42f. Therefore, the depths of the first recess 53 and the second recess 54 can be set to a depth that can suppress the first damper 81 and the second damper 82 from contacting the magnetic disks 12U, 12L.

[0104] In the HDD 10 according to the first embodiment described above, the arm 42 has a first side surface 42a, a second side surface 42b, a first surface 42c, a first seating surface 42d, a second surface 42e, and a second seating surface 42f. The first side surface 42a faces the central axis Axd of the magnetic disk 12. The second side surface 42b is located on the opposite side of the first side surface 42a and has a slit 51. The first surface 42c and the first seating surface 42d face the magnetic disk 12U. The second surface 42e and the second seating surface 42f face the magnetic disk 12L. The first seating surface 42d is farther away from the magnetic disk 12U than the first surface 42c and farther away from the central axis Axh of the arm 42 than the first surface 42c. The second seat 42f is farther away from the magnetic disk 12L than the second surface 42e, and farther away from the central axis Axh than the second surface 42e. A first recess 53 is provided in the arm 42. The first recess 53 opens to the first side surface 42a and the first surface 42c, and is closer to the central axis Axd than the slit 51 in a direction perpendicular to the central axis Axd. The suspension 62 is supported by the first seat 42d or the second seat 42f, and is partially accommodated in the slit 51. The first damper 81 is disposed in the first recess 53 and attached to the arm 42.

[0105] By being disposed in the first recess 53, the first damper 81 is spaced apart from the magnetic disk 12U compared to the case where the first damper 81 is disposed on the first surface 42c. Therefore, the first damper 81 can suppress contact with the magnetic disk 12U while damping vibration of the arm 42. In addition, the first recess 53 provided in the arm 42 avoids the portion where the first seating surface 42d and the slit 51 are provided, and spreads to reach the first side surface 42a. This suppresses the provision of the first recess 53 from affecting the design and manufacture of the first seating surface 42d on which the suspension 62 is supported and the slit 51 in which a part of the suspension 62 is accommodated. That is, the first recess 53 can suppress the first recess 53 from interfering with the attachment of the suspension 62 to the first seating surface 42d and the slit 51. In addition, the first recess 53 can be easily formed, for example, by cutting the arm 42 from the first side surface 42a with the gang cutter 100. As described above, the HDD 10 of this embodiment can improve the recording density by improving the positioning accuracy of the magnetic head 61 mounted on the suspension 62, and can be easily manufactured.

[0106] A second recess 54 is provided in the arm 42. The second recess 54 opens to the first side surface 42a and the second surface 42e, and is closer to the central axis Axd than the slit 51 in a direction perpendicular to the central axis Axd. For example, the multiple blades 101 of the gang cutter 100 cut the arm 42 from the first side surface 42a, thereby forming the first recess 53 and the second recess 54 in each of the multiple arms 42. In this case, the two adjacent blades 101 of the gang cutter 100 simultaneously form the first recess 53 and the second recess 54 in one arm 42, thereby supporting the one arm 42 from both sides and restricting the one arm 42 from bending. Therefore, the HDD 10 of this embodiment can easily form the first recess 53 and the second recess 54.

[0107] The second damper 82 is disposed in the second recess 54 and attached to the arm 42 to dampen vibrations of the arm 42. As a result, in the HDD 10 of this embodiment, the first damper 81 and the second damper 82 dampen vibrations of the arm 42, thereby enabling the positioning accuracy of the magnetic head 61 mounted on the suspension 62 to be further improved.

[0108] An edge 53b of the first recess 53 on the first surface 42c and an edge 54b of the second recess 54 on the second surface 42e are mirror images of each other. As a result, for example, the first recess 53 and the second recess 54 can be formed in each of the multiple arms 42 by cutting the arms 42 from the first surface 42c with multiple blades 101 of approximately the same shape. Therefore, in the HDD 10 of this embodiment, the first recess 53 and the second recess 54 can be easily formed.

[0109] In the Z direction along the central axis Axh, the thickness of the first damper 81 is smaller than the depth of the first recess 53. This makes it possible to prevent the first damper 81 from coming into contact with the magnetic disk 12U.

[0110] The first damper 81 has a constraining layer 85 having a higher density than the arm 42, and a viscoelastic body 86 interposed between the constraining layer 85 and the arm 42. In the Z direction along the central axis Axh, the depth of the first recess 53 is three times the thickness of the constraining layer 85. For example, if the constraining layer 85 is made of stainless steel and the arm 42 is made of an aluminum alloy, the density of the constraining layer 85 is about three times the density of the arm 42. As a result, the HDD 10 of this embodiment can reduce a change in the mass of the arm 42 caused by providing the first recess 53 in the arm 42 and disposing the first damper 81 in the first recess 53.

[0111] In the Z direction along the central axis Axh, the depth of the first recess 53 is greater than the distance between the first surface 42c and the first seating surface 42d. Therefore, the arm 42 can maintain a desired thickness between the first seating surface 42d and the second seating surface 42f regardless of the depth of the first recess 53. Therefore, the provision of the first recess 53 can suppress the influence on the design and manufacture of the first seating surface 42d on which the suspension 62 is supported. In other words, the first recess 53 can suppress the hindrance of the attachment of the suspension 62 to the first seating surface 42d.

[0112] The arm 42 is provided with a through hole 52 that opens to the first seat surface 42d and the second seat surface 42f. The suspension 62 is attached to the arm 42 by being partially fitted into the through hole 52. The first damper 81 is not line-symmetrical with respect to the center line L extending between the center axis Axh and the center of the through hole 52 in a projection view seen in the Z direction along the center axis Axh. This allows the first recess 53 to be easily formed, for example, by cutting the arm 42 from the first side surface 42a with the gang cutter 100. In addition, the first damper 81 is not restricted to a shape that is line-symmetrical. For this reason, the first damper 81 can have a shape according to other constraints or requirements, for example, in design or manufacturing. Therefore, the HDD 10 of this embodiment can be easily manufactured.

[0113] The first recess 53 tapers from the first side surface 42a to the second side surface 42b. This allows the first recess 53 to be easily formed, for example, by cutting the arm 42 from the first side surface 42a with the disc-shaped blade 101 of the gang cutter 100.

[0114] Second embodiment The second embodiment will be described below with reference to Figures 7 and 8. In the following description of the embodiments, components having the same functions as components already described are given the same reference numerals as the components already described, and further description may be omitted. Also, components given the same reference numerals do not necessarily have all the same functions and properties, and may have different functions and properties according to each embodiment.

[0115] Fig. 7 is an exemplary cross-sectional view showing an HSA 14 according to a second embodiment. As shown in Fig. 7, the HSA 14 of the second embodiment omits the second damper 82. Note that the HSA 14 of the second embodiment may include the second damper 82.

[0116] The arm 42 of the second embodiment is provided with a first recess 201 and a second recess 202 instead of the first recess 53 and the second recess 54. The first recess 201 and the second recess 202 are substantially identical to the first recess 53 and the second recess 54, except as described below.

[0117] In the Z direction along the central axis Axh, the depth of the first depression 201 is greater than the depth of the second depression 202. That is, in the Z direction along the central axis Axh, the depth of the first depression 201 is different from the depth of the second depression 202.

[0118] In the Z direction along the central axis Axh, the thickness of the first damper 81 is smaller than the depth of the first recess 201. On the other hand, in the Z direction, the thickness of the first damper 81 is greater than the depth of the second recess 202.

[0119] Fig. 8 is an exemplary cross-sectional view showing the carriage 35 and the gang cutter 100 of the second embodiment. As shown in Fig. 8, in the second embodiment, the center of the blade 101 in the Z direction is disposed at a position different from the center between two adjacent arms 42. This allows the two adjacent blades 101 to simultaneously form a deep first depression 201 and a shallow second depression 202 in each of the multiple arms 42.

[0120] Although the second recess 202 is shallow, the blade 101 contacts the arm 42 to form the second recess 202. Therefore, similar to the first embodiment, the two blades 101 support one arm 42 from both sides, thereby restricting the one arm 42 from elastically bending.

[0121] In the HDD 10 of the second embodiment described above, in the Z direction along the central axis Axh, the depth of the first recess 201 is different from the depth of the second recess 202. This makes it possible for the HDD 10 of this embodiment to easily adjust the distance between the first damper 81 and the magnetic disk 12U.

[0122] In the Z direction along the central axis Axh, the depth of the first recess 201 is greater than the depth of the second recess 202. As a result, in the HDD 10 of this embodiment, the first damper 81 can be separated from the magnetic disk 12U, and the first damper 81 can be prevented from coming into contact with the magnetic disk 12U.

[0123] In the Z direction along the central axis Axh, the thickness of the first damper 81 is smaller than the depth of the first recess 201 and larger than the depth of the second recess 202. This can prevent the first damper 81 from coming into contact with the magnetic disk 12U. Furthermore, the first recess 201 in which the first damper 81 is disposed is made deep, while the second recess 202 in which no damper is disposed is made shallow. This can prevent the arm 42 from becoming excessively thin due to the first recess 201 and the second recess 202 in the HDD 10 of this embodiment.

[0124] (Third embodiment) The third embodiment will be described below with reference to FIG. 9. FIG. 9 is an exemplary cross-sectional view showing a portion of an HSA 14 according to the third embodiment. As shown in FIG. 9, the first damper 81 of the third embodiment has a constraining layer 301 instead of the constraining layer 85. The constraining layer 301 is substantially the same as the constraining layer 85, except as described below. The constraining layer 301 of the third embodiment may replace the constraining layer 85 of either the first or second embodiment.

[0125] The constraining layer 301 has a first portion 305 and a second portion 306 that is thicker than the first portion 305. In a direction perpendicular to the central axis Axd, the first portion 305 is closer to the central axis Axd than the second portion 306.

[0126] For example, the first portion 305 is a portion of the constraining layer 301 that is closer to the central axis Axd than the center line L. The second portion 306 is a portion of the constraining layer 301 that is farther away from the central axis Axd than the center line L. Note that the first portion 305 and the second portion 306 are not limited to this example.

[0127] The constraining layer 301 tapers from the first side surface 42a to the second side surface 42b, similar to the first depression 53. Therefore, in a projection seen in the Z direction along the central axis Axh, the area of ​​the first portion 305 is larger than the area of ​​the second portion 306. On the other hand, since the second portion 306 is thicker than the first portion 305, the weight of the first portion 305 and the weight of the second portion 306 are close to each other.

[0128] The first portion 305 and the second portion 306 are integrally formed. However, the first portion 305 and the second portion 306 may be independent of each other. Also, the material of the first portion 305 and the material of the second portion 306 may be different.

[0129] In the HDD 10 of the third embodiment described above, the first damper 81 has a constraining layer 301 and a viscoelastic body 86 interposed between the constraining layer 301 and the arm 42. The constraining layer 301 has a first portion 305 and a second portion 306 that is thicker than the first portion 305. This allows the HDD 10 of this embodiment to adjust the weight balance of the first damper 81, which has an asymmetric shape.

[0130] In a direction perpendicular to the central axis Axd, the first portion 305 is closer to the central axis Axd than the second portion 306. For example, when the disk-shaped blade 101 of the gang cutter 100 forms the first recess 53, the first recess 53 tapers from the first side surface 42a to the second side surface 42b. That is, in a projection seen in the Z direction along the central axis Axh, the second portion 306 tends to be smaller than the first portion 305. However, since the second portion 306 is thicker than the first portion 305, the HDD 10 of this embodiment can adjust the weight balance in the first damper 81.

[0131] Although some embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their modifications are included in the scope and spirit of the invention, and are included in the scope of the invention and its equivalents described in the claims. [Explanation of symbols]

[0132] 10...hard disk drive (HDD), 12, 12U, 12L...magnetic disk, 42...arm, 42a...first side, 42b...second side, 42c...first surface, 42d...first seat, 42e...second surface, 42f...second seat, 51...slit, 52...through hole, 53, 201...first recess, 53a...bottom surface, 53b...edge, 54, 202...second recess, 54b...edge, 62...suspension, 81...first damper, 82...second damper, 85, 87, 301...constraint layer, 86, 88...viscoelastic body, 305...first part, 306...second part, Axd, Axh...central axis, L...center line.

Claims

1. A plurality of magnetic disks arranged along a first rotation axis and rotatable about the first rotation axis; the magnetic disks are arranged along a second rotation axis spaced apart from the first rotation axis, and each of the magnetic disks is capable of entering a gap between two adjacent magnetic disks among the plurality of magnetic disks by rotating about the second rotation axis; a first side surface facing the first rotation axis; a second side opposite the first side and having a slit; a first surface facing a first magnetic disk, the first magnetic disk being one of the two magnetic disks; a second surface facing the other of the two magnetic disks; a first bearing surface facing the first magnetic disk, spaced apart from the first magnetic disk relative to the first surface, and spaced apart from the second rotation shaft relative to the first surface; and a second bearing surface facing the second magnetic disk, spaced apart from the second magnetic disk relative to the second surface, and spaced apart from the second rotation shaft relative to the second surface; a plurality of arms each having a first recess that opens to the first side surface and the first face and is closer to the first rotation axis than the slit in a direction perpendicular to the first rotation axis; A plurality of suspensions, each of which is supported by the first seat surface or the second seat surface and partially housed in the slit, and which are attached to the plurality of arms; a plurality of first dampers, each disposed in the first recess, attached to the plurality of arms and configured to damp vibration of the plurality of arms; A disk device comprising:

2. Each of the plurality of arms is provided with a second recess that opens to the first side surface and the second surface and is closer to the first rotation axis than the slit in a direction perpendicular to the first rotation axis.

2. The disk device according to claim 1.

3. a plurality of second dampers, each disposed in the second recess, attached to the plurality of arms and configured to damp vibration of the plurality of arms; 3. The disk drive of claim 2, further comprising:

4. A depth of the first recess is different from a depth of the second recess in a direction along the second rotation axis.

3. The disk device according to claim 2.

5. In a direction along the second rotation axis, a depth of the first recess is greater than a depth of the second recess.

5. The disk device according to claim 4.

6. a thickness of the first damper in a direction along the second rotation axis is smaller than a depth of the first recess and is larger than a depth of the second recess; 6. The disk device according to claim 5.

7. an edge of the first depression on the first surface and an edge of the second depression on the second surface are mirror images of each other; 3. The disk device according to claim 2.

8. A thickness of the first damper in a direction along the second rotation axis is smaller than a depth of the first recess.

2. The disk device according to claim 1.

9. Each of the plurality of first dampers includes a constraining layer having a density greater than that of the plurality of arms, and a viscoelastic body interposed between the constraining layer and one of the plurality of arms, In a direction along the second rotation axis, a depth of the first recess is three times a thickness of the constraining layer.

2. The disk device according to claim 1.

10. In a direction along the second rotation axis, a depth of the first recess is greater than a distance between the first surface and the first seating surface.

2. The disk device according to claim 1.

11. Each of the arms is provided with a through hole that opens to the first seat surface and the second seat surface, the plurality of suspensions are attached to the plurality of arms by being partially fitted into the through holes, Each of the plurality of first dampers is not symmetrical with respect to a virtual line extending between the second rotation shaft and a center of the through hole in a projection view seen in a direction along the second rotation shaft.

2. The disk device according to claim 1.

12. The first recess tapers from the first side to the second side. The disk device according to claim 11.

13. Each of the plurality of first dampers has a constraining layer and a viscoelastic body interposed between the constraining layer and one of the plurality of arms, The constraining layer has a first portion and a second portion that is thicker than the first portion. The disk device according to claim 11.

14. In a direction perpendicular to the first rotation axis, the first portion is closer to the first rotation axis than the second portion. The disk drive according to claim 13.

15. a magnetic disk rotatable about a first rotation axis; an arm that is rotatable around a second rotation axis spaced apart from the first rotation axis, the arm having an attachment surface facing the magnetic disk and a seating surface facing the magnetic disk and spaced apart from the second rotation axis with respect to the attachment surface, the seating surface being provided with a through hole that opens into the seating surface; a suspension supported by the seat surface and attached to the arm by being partially fitted into the through hole; a damper attached to the mounting surface, configured to damp vibration of the arm, the damper not being symmetrical with respect to a virtual line extending between the second rotation axis and a center of the through hole in a projection view along the second rotation axis; A disk device comprising:

Images