Flexisha for hard disk drive suspension, and suspension for hard disk drive

Abstract

To provide a flexible suspension for hard disk drives that can suppress the deterioration of reliability. [Solution] A flexi-shaft for a hard disk drive suspension according to one embodiment is a flexi-shaft that is superimposed on a load beam provided by the hard disk drive suspension. The flexi-shaft comprises a metal base having a first surface facing the load beam and a second surface opposite to the first surface. The metal base has a mounting portion on which a slider is mounted, a fixing portion provided on the longitudinal side of the metal base toward the tip of the mounting portion and fixed to the load beam, and a pair of limiters arranged in the width direction of the metal base. Each of the pair of limiters includes a planar portion that faces the first surface or the second surface with a gap in the thickness direction of the metal base.

Description

Technical Field

[0001] The present invention relates to a flexure of a suspension for a hard disk drive and a suspension for a hard disk drive.

Background Art

[0002] A hard disk drive (HDD) is used in an information processing device such as a computer. The hard disk drive includes a magnetic disk that rotates around a spindle and a carriage that pivots around a pivot axis. The carriage has an arm and pivots around the pivot axis in the track width direction of the disk by a positioning motor such as a voice coil motor.

[0003] A suspension for a hard disk drive (hereinafter simply referred to as a suspension) is attached to the above-mentioned arm. The suspension includes a base plate connected to the arm, a load beam, and a flexure arranged along the load beam. A slider constituting a magnetic head is provided at a gimbal portion formed near the tip of the flexure.

[0004] The slider is provided with an element (transducer) for performing access such as reading or writing data. A head gimbal assembly is constituted by these load beams, flexures, sliders, and the like.

[0005] In order to cope with the high recording density of the disk, it is necessary to further miniaturize the head gimbal assembly and to be able to position the slider more accurately with respect to the recording surface of the disk.

[0006] Since there is a demand for an increase in the recording capacity of the hard disk drive in response to an improvement in the recording density, an increase in the number of magnetic disks provided in the hard disk drive (so-called multi-disk configuration) has been promoted. Along with this, thinning of the suspension has been demanded.

[0007] Furthermore, when a hard disk drive is subjected to an external shock, there is a need to suppress excessive deformation or damage to the suspension during loading and unloading, and various proposals have been made to address this (for example, Patent Document 1). [Prior art documents] [Patent Documents]

[0008] [Patent Document 1] Japanese Patent Publication No. 2021-140843 [Overview of the project] [Problems that the invention aims to solve]

[0009] However, even with the proposal in Patent Document 1, there is still room for various improvements regarding the limiter structure.

[0010] Therefore, one of the objectives of the present invention is to provide a flexure for a hard disk drive suspension and a hard disk drive suspension that can suppress a decrease in reliability. [Means for solving the problem]

[0011] A flexi-shaft for a hard disk drive suspension according to one embodiment is a flexi-shaft that is superimposed on a load beam provided by the hard disk drive suspension. The flexi-shaft comprises a metal base having a first surface facing the load beam and a second surface opposite to the first surface. The metal base has a mounting portion on which a slider is mounted, a fixing portion provided on the longitudinal side of the metal base toward the tip of the mounting portion and fixed to the load beam, and a pair of limiters arranged in the width direction of the metal base. Each of the pair of limiters includes a planar portion that faces the first surface or the second surface with a gap in the thickness direction of the metal base.

[0012] The pair of limiters may be formed by a pair of first extensions extending from the mounting portion. The planar portion may face the first surface of the fixed portion in the thickness direction.

[0013] Each of the pair of limiters may further include a first root portion connected to the mounting portion and a first intermediate portion between the first root portion and the planar portion. The fixing portion may be located in the width direction between the first intermediate portions of the pair of limiters.

[0014] The pair of limiters may be formed by a pair of second extensions extending from the fixed portion. The planar portion may face the second surface of the mounting portion in the thickness direction. Each of the pair of limiters may further include a second root portion connected to the fixed portion and a second intermediate portion connecting the second root portion and the planar portion.

[0015] The flexure may further include a wiring section disposed between the second surface and the flat surface of the mounting section. The metal base may further include a frame section disposed on the outside of the mounting section. The fixing section may be located between the mounting section and the frame section in the longitudinal direction.

[0016] The metal base may further have a frame portion disposed on the outside of the mounting portion. The frame portion may be located between the mounting portion and the fixing portion in the longitudinal direction. The planar portion may further face the second surface of the frame portion in the thickness direction.

[0017] The metal base may further have a frame portion disposed outside the mounting portion. The pair of limiters may be formed by a pair of first extensions extending from the mounting portion. The planar portion may face the first surface of the frame portion in the thickness direction.

[0018] Each of the pair of limiters may further include a first root portion connected to the mounting portion and a first intermediate portion connecting the first root portion and the planar portion. The fixing portion may be located between the mounting portion and the frame portion in the longitudinal direction. The frame portion may be located between the mounting portion and the fixing portion in the longitudinal direction. The flexure may further include a cover member formed of a resin material and disposed on the planar portion.

[0019] A suspension for a hard disk drive according to one embodiment comprises a load beam and a flexure superimposed on the load beam. The flexure includes a metal base having a first surface facing the load beam and a second surface opposite the first surface.

[0020] The metal base includes a mounting portion on which the slider is mounted, a fixing portion provided on the tip side of the mounting portion in the longitudinal direction of the metal base and fixed to the load beam, and a pair of limiters arranged in the width direction of the metal base. Each of the pair of limiters includes a planar portion that faces the first or second surface with a gap between them in the thickness direction of the metal base.

[0021] The pair of limiters may be formed by a pair of first extensions extending from the mounting portion. The planar portion may face the first surface of the fixed portion in the thickness direction.

[0022] The pair of limiters may be formed by a pair of second extensions extending from the fixed portion. The planar portion may face the second surface of the mounting portion in the thickness direction.

[0023] The metal base may further have a frame portion disposed outside the mounting portion. The pair of limiters may be formed by a pair of first extending portions extending from the mounting portion. The flat portion may face the first surface of the frame portion in the thickness direction. The suspension for a hard disk drive may be formed of a resin material and may further include a cover member disposed on the flat portion.

Advantages of the Invention

[0024] According to the present invention, it is possible to provide a flexure of a suspension for a hard disk drive capable of suppressing a decrease in reliability, and a suspension for a hard disk drive.

Brief Description of the Drawings

[0025] [Figure 1] FIG. 1 is a schematic perspective view showing an example of a hard disk drive. [Figure 2] FIG. 2 is a schematic cross-sectional view showing a part of the hard disk drive. [Figure 3] FIG. 3 is a schematic plan view of a suspension according to the first embodiment. [Figure 4] FIG. 4 is a schematic plan view of a flexure according to the first embodiment. [Figure 5] FIG. 5 is a schematic perspective view of a flexure according to the first embodiment. [Figure 6] FIG. 6 is a schematic cross-sectional view of a flexure according to the first embodiment. [Figure 7] FIG. 7 is a schematic plan view showing a manufacturing process of a limiter according to the first embodiment. [Figure 8] FIG. 8 is a schematic plan view showing a manufacturing process of a limiter according to the first embodiment. [Figure 9] FIG. 9 is a schematic plan view showing a manufacturing process of a limiter according to the first embodiment. [Figure 10] FIG. 10 is a schematic plan view showing a flexure included in a suspension according to the second embodiment. [Figure 11] Figure 11 is a schematic plan view showing the metal base before the limiter is formed. [Figure 12] Figure 12 is a schematic plan view showing the flexure of the suspension according to the third embodiment. [Figure 13] Figure 13 is a schematic plan view showing the metal base before the limiter is formed. [Figure 14] Figure 14 is a schematic plan view showing the flexure of the suspension according to the fourth embodiment. [Figure 15] Figure 15 is a schematic enlarged view of the area near the limiter shown in Figure 14. [Figure 16] Figure 16 is a schematic plan view showing the metal base before the limiter is formed. [Figure 17] Figure 17 is a schematic plan view showing the flexure of the suspension according to the fifth embodiment. [Figure 18] Figure 18 is a schematic enlarged view of the area near the limiter shown in Figure 17. [Figure 19] Figure 19 is a schematic plan view showing the metal base before the limiter is formed. [Figure 20] Figure 20 is a schematic plan view showing the flexure of the suspension according to the sixth embodiment. [Figure 21] Figure 21 is a schematic cross-sectional view of the flexi shown in Figure 20. [Modes for carrying out the invention]

[0026] The embodiments of the present invention will be described below with reference to the drawings. In order to make the explanation clearer, the size, shape, etc. of each part may be schematically represented in the drawings with modifications from the actual embodiments.

[0027] [First Embodiment] Figure 1 is a schematic perspective view showing an example of a hard disk drive 1 (HDD). In the example in Figure 1, the hard disk drive 1 comprises a case 2, a plurality of magnetic disks (hereinafter simply referred to as disks 4) that rotate around a spindle 3, a carriage 6 that can pivot around a pivot axis 5, and a positioning motor (voice coil motor) 7 for driving the carriage 6. The case 2 is sealed by a lid (not shown).

[0028] Figure 2 is a schematic cross-sectional view showing a part of the hard disk drive 1. As shown in Figure 2, the carriage 6 is provided with multiple (for example, three) arms 8. The number of arms 8 provided on the carriage 6 is not limited to the example described above.

[0029] Multiple arms 8 each have a hard disk drive suspension (hereinafter referred to as suspension 10) attached to their tips. Furthermore, each suspension 10 has a slider 11 that constitutes a magnetic head.

[0030] As disc 4 rotates at high speed, air flows between disc 4 and slider 11, forming an air bearing. When the carriage 6 is rotated by the positioning motor 7, the suspension 10 moves radially around disc 4, causing slider 11 to move to the desired track on disc 4.

[0031] Figure 3 is a schematic plan view of the suspension 10 according to this embodiment. The suspension 10 comprises a base plate 20 connected to an arm 8 (shown in Figure 2), a load beam 30, and a flexure 40.

[0032] In Figure 3 and subsequent figures, the X, Y, and Z axes are shown as mutually orthogonal. The direction along the X-axis is defined as the first direction X, the direction along the Y-axis as the second direction Y, and the direction along the Z-axis as the third direction Z. Viewing each element parallel to the third direction Z is called a plan view.

[0033] Here, the first direction X corresponds to the longitudinal direction of the suspension 10, base plate 20, load beam 30, and flexisha 40. In the first direction X, with respect to the base plate 20, the side on which the slider constituting the magnetic head is mounted may be called the tip or tip side.

[0034] Furthermore, the second direction Y corresponds to the width direction of the suspension 10, base plate 20, load beam 30, and flexure 40, and the third direction Z corresponds to the thickness direction of the suspension 10, base plate 20, load beam 30, and flexure 40. Hereafter, the length along the third direction Z may be referred to as the thickness. In addition, a sway direction S is defined near the tip of the load beam 30, indicated by an arc-shaped arrow.

[0035] The base plate 20 is made of a metal material such as stainless steel. The base plate 20 has a cylindrical boss portion 21 for connecting to the arm 8 (shown in Figure 2).

[0036] The load beam 30 is made of a metallic material such as stainless steel. The thickness of the load beam 30 is, for example, 30 to 80 μm. The load beam 30 has a tapered shape towards the tip.

[0037] As shown in Figure 3, the load beam 30 is connected to the base plate 20 by spot welding, for example, using a laser, at multiple welds W. Specifically, the load beam 30 is elastically supported by the base plate 20 via a pair of spring sections 31 that include multiple welds W. The load beam 30 has a surface 30A on which the flexi 40 is positioned.

[0038] The flexi-shaft 40 is positioned along the base plate 20 and the load beam 30. The flexi-shaft 40 overlaps the surface 30A of the load beam 30. In addition, a portion of the flexi-shaft 40 extends rearward beyond the base plate 20.

[0039] The flexi-sha 40 comprises a metal base 41 and a wiring section 50 superimposed on the metal base 41. The metal base 41 is formed from, for example, a thin stainless steel plate. The thickness of the metal base 41 is less than the thickness of the load beam 30. The thickness of the metal base 41 is, for example, 15 to 20 μm.

[0040] The metal base 41 is fixed to the base plate 20 and the load beam 30 by, for example, spot welding using a laser at multiple welds W. The metal base 41 has a surface 411 (first surface) facing the surface 30A of the load beam 30, and a surface 413 (second surface) opposite to surface 411. Surface 411 faces in the direction opposite to the third direction Z, and surface 413 faces in the third direction Z. Surface 413 corresponds to the surface on which the wiring section 50 is arranged.

[0041] The wiring section 50 includes a base insulating layer, a conductor layer superimposed on the base insulating layer, and a cover insulating layer superimposed on the conductor layer. The conductor layer includes, for example, wiring for reading and wiring for writing. These multiple wirings are covered by the cover insulating layer.

[0042] The metal base 41 further includes a tongue portion 42, a frame portion 43, and a fixing portion 44 near the tip of the suspension 10. The tongue portion 42, the frame portion 43, and the fixing portion 44 are all parts of the metal base 41, and their respective contours are formed, for example, by etching.

[0043] The tongue portion 42, the frame portion 43, and the fixing portion 44 each have surfaces 411 and 413, respectively. Each of the surfaces 411 and 413 is, for example, an unetched surface (rolled surface).

[0044] The center of the second direction Y of the tongue portion 42 roughly coincides with the center of the second direction Y of the fixing portion 44. The centers of the second direction Y of the tongue portion 42 and the fixing portion 44 roughly coincide with the center of the second direction Y of the suspension 10.

[0045] The tongue portion 42 is mounted on the slider 11 that constitutes the magnetic head. In this embodiment, the tongue portion 42 corresponds to the mounting portion on which the slider 11 is mounted. The tongue portion 42 includes the portion that overlaps with the slider 11 and the portion in its vicinity. In Figure 3, the slider 11 is shown by a dashed line. The tip of the slider 11 is provided with an element capable of converting magnetic signals and electrical signals, such as an MR element.

[0046] The wiring section 50 is electrically connected to the elements of the slider 11 via terminals for the slider 11. Note that the terminals for the slider 11 are omitted in each figure for simplicity. These elements perform access such as writing or reading data to the disk 4 (shown in Figure 2). The head gimbal assembly is composed of the slider 11, load beam 30, flexure 40, etc.

[0047] The frame portion 43 is positioned outside the tongue portion 42, surrounding the tongue portion 42. Furthermore, in this embodiment, the frame portion 43 is positioned outside the fixing portion 44, surrounding the fixing portion 44.

[0048] The frame section 43 includes a pair of outriggers 45A and 45B. In the example shown in Figure 3, the frame section 43 connects outriggers 45A and 45B at a tip end of the tongue section 42 and the fixed section 44. The outriggers 45A and 45B are located on either side of the tongue section 42 in the second direction Y.

[0049] The metal base 41 is fixed to the load beam 30 at the fixing portion 44 by a welded portion W (welded portion W1 shown in Figure 3). The fixing portion 44 is located on the tip side of the tongue portion 42 in the first direction X.

[0050] The fixing portion 44 is located between the tongue portion 42 and the frame portion 43 in the first direction X. In other words, the tongue portion 42, the fixing portion 44, and the frame portion 43 are arranged in this order in the first direction X.

[0051] The fixed portion 44 is not connected to the tongue portion 42 in the first direction X. In contrast, the fixed portion 44 is connected to the frame portion 43 via the connecting portion 46 in the first direction X. The width of the connecting portion 46 in the second direction Y is smaller than the width of the fixed portion 44 in the second direction Y.

[0052] The load beam 30 has dimples 32 (shown by dashed lines in Figure 3) that protrude toward the tongue portion 42. The tips of the dimples 32 are in contact with the surface 411 on the tongue portion 42.

[0053] The tongue portion 42 is shaped to pivot around the tip of the dimple 32, enabling the desired gimbal motion. The gimbal portion 47 is composed of the tongue portion 42, a pair of outriggers 45A and 45B, the dimple 32, and the like.

[0054] Actuators 60A and 60B are mounted on the gimbal section 47. Actuators 60A and 60B have the function of rotating the tongue section 42 in the sway direction S. Actuators 60A and 60B are, for example, piezoelectric elements and are made of lead zirconate titanate (PZT) or the like.

[0055] Actuators 60A and 60B are positioned on both sides of the slider 11 in the second direction Y. Actuators 60A and 60B are fixed to the tongue portion 42 by conductive adhesive or the like.

[0056] The following description focuses on the area near the tip of the Flexi-sha 40 and explains the metal base 41 in this embodiment.

[0057] Figure 4 is a schematic plan view of the flexi-sha 40 according to this embodiment. Figure 5 is a schematic perspective view of the flexi-sha 40 according to this embodiment. Figure 6 is a schematic cross-sectional view of the flexi-sha 40 according to this embodiment.

[0058] In Figures 4 to 6, the load beam 30 is omitted. In Figure 4, a portion of the wiring section 50 and slider 11 overlapping the tongue section 42 is shown, while the wiring section 50 and slider 11 overlapping the tip portion of the tongue section 42 to which the limiter described later is connected are omitted from the illustration. In Figure 5, the flexiser 40 is shown in cross-section. In Figure 6, the flexiser 40 is viewed in the second direction Y.

[0059] As described above, the flexi-sha 40 comprises a metal base 41 and a wiring section 50. The metal base 41 has a tongue section 42, a frame section 43, and a fixing section 44. In the first direction X, a gap G1 extending in the second direction Y is formed between the tongue section 42 and the fixing section 44, as shown in Figure 4.

[0060] The metal base 41 further includes limiters 70A and 70B, as shown in Figure 4. In this embodiment, limiters 70A and 70B correspond to a pair of limiters. In the examples in Figures 5 and 6, limiter 70B is shown.

[0061] The limiters 70A and 70B are aligned in the second direction Y. In this embodiment, the limiters 70A and 70B extend from the tongue portion 42. Each of the limiters 70A and 70B is formed, for example, by bending a part of the metal base 41 that extends from the tongue portion 42. The limiter 70A has a shape that is symmetrical to the limiter 70B with respect to a hypothetical straight line extending in the second direction Y.

[0062] Each of the limiters 70A and 70B includes a root portion 71 (first root portion), a flat portion 73, and an intermediate portion 75 (first intermediate portion) between the root portion 71 and the flat portion 73, as shown in Figure 4. The root portion 71, the flat portion 73, and the intermediate portion 75 are formed integrally, for example. The root portion 71, the flat portion 73, and the intermediate portion 75 each have surfaces 411 and 413, respectively.

[0063] The root portion 71 is connected to the tongue portion 42. Specifically, as shown in Figure 4, the root portion 71 extends from the tongue portion 42 in the first direction X. The distance between adjacent root portions 71 in the second direction Y is greater than the width of the fixing portion 44 in the second direction Y.

[0064] The planar portion 73 faces either surface 411 or surface 413 with a gap in the third direction Z. Here, "facing each other" includes not only the case where each element is parallel to each other, but also the case where one element is inclined relative to the other. Furthermore, "facing each other" includes not only the case where no other elements are placed between each element, but also the case where other elements are placed between each element.

[0065] In this embodiment, the planar portion 73 faces the surface 411 of the fixing portion 44, as shown in Figure 6. More specifically, the surface 411 of the planar portion 73 faces the surface 411 of the fixing portion 44.

[0066] As shown in Figure 4, the planar portion 73 overlaps the fixed portion 44 in a plan view. The planar portion 73 and the fixed portion 44 are arranged in this order in the third direction Z. The tip of the planar portion 73 is located near the side of the load beam 30 in the second direction Y in a plan view. In the portion where the fixed portion 44 overlaps with the load beam 30, its width in the second direction Y is greater than that of the load beam 30. The fixed portion 44 has overlapping portions 440 at both ends in the second direction Y that overlap with the planar portion 73.

[0067] The flat portion 73 is separated from the surface 411 of the fixed portion 44. In this embodiment, as shown in Figure 6, a gap G2 is formed between the surface 411 of the flat portion 73 and the surface 411 of the fixed portion 44 in the third direction Z.

[0068] As shown in Figure 4, the fixed portion 44 is located in the second direction Y between the intermediate portion 75 of limiter 70A and the intermediate portion 75 of limiter 70B. The intermediate portion 75 is not in contact with the fixed portion 44.

[0069] As shown in Figure 4, in a plan view, the planar portion 73 of limiter 70A extends in the second direction Y relative to the fixed portion 44, and the planar portion 73 of limiter 70B extends in the direction opposite to the second direction Y relative to the fixed portion 44.

[0070] As shown in Figures 5 and 6, the limiter 70B further includes a bent portion 77 connecting the intermediate portion 75 and the flat portion 73, and a bent portion 79 connecting the intermediate portion 75 and the base portion 71. Although not shown, the limiter 70A also includes bent portions 77 and 79, similar to the limiter 70B.

[0071] Next, an example of a manufacturing method for limiters 70A and 70B will be described. Figures 7 to 9 are schematic plan views showing the manufacturing process of limiters 70A and 70B according to this embodiment.

[0072] Figure 7 shows the metal base 41 before the limiters 70A and 70B are formed. As shown in Figure 7, the metal base 41 has extensions 700A and 700B. In this embodiment, the extensions 700A and 700B correspond to a pair of first extensions.

[0073] The limiters 70A and 70B are formed by bending the extensions 700A and 700B. Specifically, the limiters 70A and 70B are formed by bending the extensions 700A and 700B twice.

[0074] The extensions 700A and 700B extend from the tongue portion 42 in the first direction X. The fixed portion 44 is located between the extensions 700A and 700B in a plan view. The extension 700A, the fixed portion 44, and the extension 700B are arranged in this order in the second direction Y.

[0075] In the example shown in Figure 7, the bending lines L1 and L2 indicate the positions where the extensions 700A and 700B are bent. A flat section 73 is formed on the tip side of the bending line L1, an intermediate section 75 is formed between the bending line L1 and the bending line L2, and a base section 71 is formed between the bending line L2 and the tongue section 42.

[0076] The curved lines L1 and L2 are inclined with respect to the second direction Y. Specifically, the curved lines L1 and L2 of the extension 700A are inclined to move away from the tongue portion 42 as they advance in the second direction Y. In contrast, the curved lines L1 and L2 of the extension 700B are inclined to move away from the tongue portion 42 as they advance in the direction opposite to the second direction Y.

[0077] First, the extensions 700A and 700B are bent along the bending line L1. Specifically, as shown in Figure 8, the portion closer to the tip than the bending line L1 is bent in the opposite direction (downward) to the third direction Z. This forms the bent portion 77.

[0078] Next, the extensions 700A and 700B are bent along the bending line L2. Specifically, as shown in Figure 9, the portion closer to the tip than the bending line L2 is bent in the opposite direction (downward) to the third direction Z. This forms the bent portion 79.

[0079] As described above, the extensions 700A and 700B are bent along the bending lines L1 and L2, respectively, so that the flat portion 73 is positioned below the fixed portion 44. As a result, the surface 411 of the flat portion 73 faces the surface 411 of the fixed portion 44.

[0080] The limiters 70A and 70B suppress the tongue portion 42 from moving too far away from the dimple 32 or from excessive gimbal movement when the suspension 10 is subjected to an external impact. Specifically, the flat portion 73 of the limiters 70A and 70B contacts the fixed portion 44, thereby suppressing the movement of the tongue portion 42. This suppresses deformation and damage to the suspension 10.

[0081] In this embodiment, the limiters 70A and 70B of the flexiser 40 include a planar portion 73 that faces the surface 411 of the fixed portion 44 with a gap G2 (shown in Figure 6) in the third direction Z. Therefore, when the suspension 10 is subjected to an external impact, the surface 411 of the planar portion 73 and the surface 411 of the fixed portion 44 come into contact.

[0082] As a comparative example, we assume that the edge (end face) of the limiter faces the surface of the fixed part 44. In this embodiment, when the surface 411 of the flat part 73 and the surface 411 of the fixed part 44 are in contact, the contact area can be made larger than in the comparative example. As a result, the load at contact is distributed and the pressure per unit area at contact is reduced. Consequently, wear at contact can be suppressed.

[0083] Furthermore, if the edge of the limiter is an etched surface, surface 411 (rolled surface) is smoother than the etched surface, allowing for a larger contact area than in the comparative example. This distributes the load more widely during contact, resulting in lower pressure per unit area during contact. Moreover, the rolled surface is harder and less prone to deformation than the etched surface. As a result, wear during contact can be suppressed. Wear during contact can generate foreign matter such as dust and particles (contamination). The generation of such foreign matter can reduce the reliability of the hard disk drive. In this embodiment, foreign matter is less likely to be generated than in the comparative example described above.

[0084] In particular, the floating height of the slider relative to the magnetic disk tends to decrease. For example, thermal expansion caused by a heater located at the tip of the magnetic head may cause a portion of it to pop out, or the area around the element may be brought even closer to the media (magnetic disk).

[0085] In such cases, the gap between the slider and the magnetic disk (Head Media Spacing) is very small (for example, less than 1 nm). In this embodiment, the generation of foreign matter can be suppressed, and thus the occurrence of malfunctions in the hard disk drive caused by foreign matter can be suppressed. Thus, in this embodiment, the deterioration of the reliability of the hard disk drive can be suppressed.

[0086] In this embodiment, the limiter structure is formed by the limiters 70A, 70B and the fixing portion 44. Since the limiters 70A, 70B and the fixing portion 44 are each part of the metal base 41, the limiter structure can be easily formed. For example, it is easy to adjust the degree of overlap between the planar portion 73 of the limiters 70A, 70B and the fixing portion 44.

[0087] When a limiter structure is formed by a load beam and a flexi-shaft, the limiter on the flexi-shaft needs to be hooked onto a part of the load beam during assembly, which can sometimes result in improper hooking or deformation.

[0088] In this embodiment, a limiter structure can be formed that is less affected by the assembly accuracy of the load beam 30 and the flexure 40. In other words, in this embodiment, assembly of the flexure 40 and the load beam 30 becomes easier.

[0089] Furthermore, in this embodiment, since the limiters 70A and 70B are formed by bending a part of the metal base 41 twice, the height of the limiters 70A and 70B can be reduced. Here, the height is, for example, the length of the limiters 70A and 70B along the third direction Z.

[0090] By reducing the height of limiters 70A and 70B, the height of limiters 70A and 70B will have less impact on the thickness of the suspension 10, making it possible to accommodate the use of multiple disk drives in the hard disk drive.

[0091] With the flexi-shaft 40 and suspension 10 equipped with the flexi-shaft 40 configured as described above, a decrease in reliability can be suppressed. In addition, various other desirable effects can be obtained from this embodiment.

[0092] Next, other embodiments will be described. In the other embodiments described below, components similar to those in the first embodiment described above will be given the same reference numerals as in the first embodiment, and their detailed descriptions may be omitted or simplified.

[0093] [Second Embodiment] Figure 10 is a schematic plan view showing the flexure 40 of the suspension 10 according to this embodiment. This embodiment differs from the first embodiment in that the limiters 70A and 70B extend from the fixed portion 44.

[0094] Each of the limiters 70A and 70B is formed, for example, by bending a portion of the metal base 41 extending from the fixed portion 44. Each of the limiters 70A and 70B includes a root portion 71 (second root portion), a flat portion 73, and an intermediate portion 75 (second intermediate portion) between the root portion 71 and the flat portion 73, as shown in Figure 10.

[0095] The base portion 71 is connected to the fixed portion 44. The base portion 71 of limiter 70A extends from the fixed portion 44 in the direction opposite to the second direction Y, and the base portion 71 of limiter 70B extends from the fixed portion 44 in the second direction Y. In other words, the base portion 71 of limiter 70B extends in the direction opposite to that of the base portion 71 of limiter 70A.

[0096] In this embodiment, the flat portion 73 faces the surface 413 of the tongue portion 42. Specifically, the surface 413 of the flat portion 73 faces the surface 413 of the tongue portion 42, with the wiring portion 50 in between.

[0097] In other words, a portion of the wiring section 50 is positioned between the surface 413 of the tongue section 42 and the planar section 73. Also, the planar section 73 overlaps the tongue section 42 in a plan view. The load beam 30, tongue section 42, wiring section 50, and planar section 73 are arranged in this order in the third direction Z. The wiring section 50 has an overlapping portion 500 that overlaps the planar section 73 at its end near the fixed section 44.

[0098] The flat portion 73 is separated from the wiring portion 50. In this embodiment, as shown in Figure 10, a gap G2 is formed between the flat portion 73 and the wiring portion 50 in the third direction Z. The flat portion 73 faces the surface 413 of the tongue portion 42 with a gap G2 between them.

[0099] The two flat sections 73 extend from the tip side in a direction opposite to the first direction X relative to the tongue section 42. The intermediate section 75 is not in contact with the tongue section 42. The limiters 70A and 70B further include a bent section 77 connecting the intermediate section 75 and the flat section 73, and a bent section 79 connecting the intermediate section 75 and the base section 71.

[0100] Next, an example of a manufacturing method for the limiters 70A and 70B in this embodiment will be described. Figure 11 is a schematic plan view showing the metal base 41 before the limiters 70A and 70B are formed.

[0101] As shown in Figure 11, the metal base 41 has extensions 700A and 700B. In this embodiment, the extensions 700A and 700B correspond to a pair of second extensions. The limiters 70A and 70B are formed by bending the extensions 700A and 700B. Specifically, the limiters 70A and 70B are formed by bending the extensions 700A and 700B twice.

[0102] The extension portion 700A extends from the fixed portion 44 in the direction opposite to the second direction Y, and the extension portion 700B extends from the fixed portion 44 in the second direction Y. The extension portions 700A and 700B are located between the tongue portion 42 and the frame portion 43 in the first direction X.

[0103] In the example shown in Figure 11, the bending lines L1 and L2 indicate the positions where the extensions 700A and 700B are bent. A flat section 73 is formed on the tip side of the bending line L1, an intermediate section 75 is formed between the bending line L1 and the bending line L2, and a base section 71 is formed between the bending line L2 and the tongue section 42. The bending lines L1 and L2 are inclined with respect to the first direction X. Specifically, the bending lines L1 and L2 are inclined to approach the fixing section 44 as they proceed in the first direction X.

[0104] First, the extensions 700A and 700B are bent along the bending line L1. Specifically, the portion closer to the tip of the bending line L1 is bent so that it faces the third direction Z (upward). This forms the bent portion 77.

[0105] Next, the extensions 700A and 700B are bent along the bending line L2. Specifically, the portion closer to the tip than the bending line L2 is bent so that it faces the third direction Z (upward). This forms the bent portion 79. This forms the limiters 70A and 70B shown in Figure 10.

[0106] The extensions 700A and 700B are bent along the bending lines L1 and L2, respectively, so that the flat section 73 is positioned above the wiring section 50. As a result, the flat section 73 faces the wiring section 50.

[0107] In this embodiment, the limiter structure is formed by the limiters 70A, 70B and the fixing part 44. The same effects as in the first embodiment can be obtained with the configuration of this embodiment as well. In this embodiment, the surface 413 of the planar part 73 and the wiring part 50 face each other.

[0108] Therefore, when the suspension 10 is subjected to an external impact, the surface 413 of the flat portion 73 and the upper surface of the wiring portion 50 come into contact. Since the upper surface of the wiring portion 50 is made of a soft resin material (for example, polyimide), the contact area with the surface 413 can be increased. As a result, the load at the time of contact is distributed, and the pressure per unit area at the time of contact is reduced. Consequently, wear at the time of contact is suppressed, and foreign matter is less likely to be generated.

[0109] Furthermore, in this embodiment as well, since the limiters 70A and 70B are formed by bending a part of the metal base 41 twice, the height of the limiters 70A and 70B can be reduced. By reducing the height of the limiters 70A and 70B, it is possible to accommodate sliders with a small thickness. In other words, by reducing the height of the limiters 70A and 70B, it is possible to suppress the limiters 70A and 70B from protruding beyond the slider in the third direction Z.

[0110] [Third Embodiment] Figure 12 is a schematic plan view showing the flexure 40 provided in the suspension 10 according to this embodiment. In this embodiment, the arrangement of the frame portion 43 and the fixing portion 44 differs from that of the second embodiment.

[0111] In this embodiment, the frame portion 43 is located between the tongue portion 42 and the fixing portion 44 in the first direction X. In other words, the tongue portion 42, the frame portion 43, and the fixing portion 44 are arranged in this order in the first direction X. The connecting portion 46 extends from the frame portion 43 in the first direction X.

[0112] In the first direction X, a gap G1 extending in the second direction Y is formed between the tongue portion 42 and the frame portion 43. In other words, the frame portion 43 is not connected to the tongue portion 42 in the first direction X.

[0113] Each of the limiters 70A and 70B includes a root portion 71 (second root portion), a flat portion 73, and an intermediate portion 75 (second intermediate portion) between the root portion 71 and the flat portion 73, as shown in Figure 12.

[0114] In this embodiment, the length of the planar portion 73 in the first direction X is longer than the length of the planar portion 73 in the first direction X in the second embodiment. In this embodiment, the planar portion 73 faces the surface 413 of the tongue portion 42. Specifically, the surface 413 of the planar portion 73 faces the surface 413 with the wiring portion 50 in between. Furthermore, the surface 413 of the planar portion 73 faces the surface 413 of the frame portion 43 in the third direction Z.

[0115] Figure 13 is a schematic plan view showing the metal base 41 before the limiters 70A and 70B are formed. The tongue portion 42, the frame portion 43, and the extension portions 700A and 700B are arranged in this order in the first direction X.

[0116] In this embodiment as well, the extensions 700A and 700B are bent along the bending lines L1 and L2, respectively, so that the flat portion 73 is positioned above the wiring portion 50. As a result, the flat portion 73 faces the wiring portion 50.

[0117] In this embodiment, the same effects as in the second embodiment can be obtained. In this embodiment, the surface 413 of the planar portion 73 faces not only the wiring portion 50 but also the surface 413 of the frame portion 43. In other words, the planar portion 73 overlaps the metal base 41 over a larger area compared to the second embodiment. This makes it easier to suppress the movement of the tongue portion 42.

[0118] [Fourth Embodiment] Figure 14 is a schematic plan view showing the flexure 40 of the suspension 10 according to this embodiment. Figure 15 is a schematic enlarged view of the vicinity of the limiters 70A and 70B shown in Figure 14. In this embodiment, the elements that the planar portion 73 faces differ from those in the first embodiment.

[0119] In a plan view, the frame portion 43 has a shape that is convex in the first direction X. Specifically, the central part of the portion of the frame portion 43 that connects the outriggers 45A and 45B in the second direction Y (the part that overlaps with the fixing portion 44 in the first direction X) protrudes in the first direction X.

[0120] In this embodiment, the limiters 70A and 70B extend from the tip of the tongue portion 42. Each of the limiters 70A and 70B is formed, for example, by bending a part of the metal base 41 that extends from the tongue portion 42.

[0121] The base portion 71 of limiter 70A extends from the fixing portion 44 in the direction opposite to the second direction Y, and the base portion 71 of limiter 70B extends from the fixing portion 44 in the second direction Y. In this embodiment, the surfaces 411 of the planar portions 73 of limiters 70A and 70B face the surface 411 of the frame portion 43, as shown in Figure 15.

[0122] In a plan view, the planar portion 73 overlaps with the frame portion 43. The planar portion 73 and the frame portion 43 are arranged in this order in the third direction Z.

[0123] The flat portion 73 is separated from the surface 411 of the frame portion 43. In this embodiment, as shown in Figure 15, a gap G2 is formed between the flat portion 73 and the surface 411 of the frame portion 43 in the third direction Z. The intermediate portion 75 is not in contact with the frame portion 43.

[0124] Figure 16 is a schematic plan view showing the metal base 41 before the limiters 70A and 70B are formed. In this embodiment, the extensions 700A and 700B correspond to a pair of first extensions.

[0125] The extension portion 700A extends from the tip portion 421 of the tongue portion 42 in the direction opposite to the second direction Y, and the extension portion 700B extends from the tip portion 421 of the tongue portion 42 in the second direction Y. The tongue portion 42, the extension portions 700A and 700B, and the frame portion 43 are arranged in this order in the first direction X.

[0126] The bending lines L1 and L2 are inclined to move away from the tip portion 421 as they proceed in the first direction X. As the extensions 700A and 700B are bent along the bending lines L1 and L2, respectively, the flat portion 73 is positioned below the frame portion 43. As a result, the flat portion 73 faces the surface 411 of the frame portion 43.

[0127] In the configuration of this embodiment, the same effects as in the first embodiment can be obtained. Note that the planar portion 73 may protrude further in the first direction X than the frame portion 43 in a plan view.

[0128] [Fifth Embodiment] Figure 17 is a schematic plan view showing the flexure 40 of the suspension 10 according to this embodiment. Figure 18 is a schematic enlarged view of the vicinity of the limiters 70A and 70B shown in Figure 17. In this embodiment, the arrangement of the frame portion 43 and the fixing portion 44 differs from that of the fourth embodiment.

[0129] In this embodiment, the frame portion 43 is located between the tongue portion 42 and the fixing portion 44 in the first direction X. In other words, the tongue portion 42, the frame portion 43, and the fixing portion 44 are arranged in this order in the first direction X. The connecting portion 46 extends from the frame portion 43 in the first direction X.

[0130] In a plan view, the planar portion 73 overlaps the frame portion 43. The planar portion 73 and the frame portion 43 are arranged in this order in the third direction Z. In a plan view, the planar portion 73 protrudes from the frame portion 43 in the first direction X, but it does not have to protrude. In this embodiment, as shown in Figure 18, a gap G2 is formed between the planar portion 73 and the surface 411 of the frame portion 43 in the third direction Z.

[0131] Figure 19 is a schematic plan view showing the metal base 41 before the limiters 70A and 70B are formed. The tongue portion 42, the extension portions 700A and 700B, and the frame portion 43 are arranged in this order in the first direction X.

[0132] In this embodiment as well, the extensions 700A and 700B are bent along the bending lines L1 and L2, respectively, so that the flat portion 73 is positioned below the frame portion 43. As a result, the flat portion 73 faces the surface 411 of the frame portion 43.

[0133] The same effects as those of the fourth embodiment can be obtained with the configuration of this embodiment as well.

[0134] [Sixth Embodiment] Figure 20 is a schematic plan view showing the flexure 40 provided in the suspension 10 according to this embodiment. Figure 21 is a schematic cross-sectional view of the flexure 40 shown in Figure 20.

[0135] This embodiment differs from the first embodiment in that the flexi-sha 40 further comprises a cover member 90. In Figures 20 and 21, dots are shown on the cover member 90. The cover member 90 is formed of a resin material (for example, polyimide).

[0136] The cover member 90 is positioned on the flat portion 73 of the limiters 70A and 70B, respectively. The cover member 90 is positioned on at least a portion of the flat portion 73. In this embodiment, the cover member 90 is positioned on the surface 411 of the flat portion 73. The cover member is positioned, for example, to overlap the entire surface 411 of the flat portion 73.

[0137] Furthermore, the cover member may be positioned not only on the flat portion 73, but also on at least a portion of the base portion 71 and the intermediate portion 75. As shown in Figure 21, the cover member 90 faces the surface 411 of the fixing portion 44. A gap G2 is formed between the cover member 90 and the surface 411 of the fixing portion 44 in the third direction Z.

[0138] In the configuration of this embodiment, the same effects as in the first embodiment can be obtained. In this embodiment, a cover member 90 is further provided, which is arranged on the flat portion 73. As described above, the cover member 90 faces the surface 411 of the fixing portion 44.

[0139] For example, if subjected to an external impact, the cover member 90 comes into contact with the surface 411. Therefore, compared to the case where elements made of metal materials come into contact with each other, as in the first embodiment, the generation of foreign matter can be suppressed more effectively.

[0140] Furthermore, the cover member 90 in this embodiment can be applied to the flexi-shaft 40 in the second to fifth embodiments, respectively.

[0141] For example, in the second and third embodiments, the cover member 90 is positioned on the surface 413 of the flat portion 73. In this case, the cover member 90 faces the surface 413 of the tongue portion 42, with the wiring portion 50 in between. In other words, elements formed from resin material face each other.

[0142] Furthermore, in the third embodiment, the cover member 90 also faces the surface 413 of the frame portion 43. Therefore, compared to the case where elements made of metal material come into contact with each other, the generation of foreign matter can be suppressed to a greater extent.

[0143] In the fourth and fifth embodiments, the cover member 90 is positioned on the surface 411 of the planar portion 73. In this case, the cover member 90 faces the surface 411 of the frame portion 43. Thus, the cover member 90 faces the surface 411 or surface 413 of the metal base 41.

[0144] In implementing each of the above embodiments, the specific forms of each element constituting the hard disk drive, including the specific forms of the load beam and flexi-shaft, can be changed in various ways.

[0145] Various embodiments can be formed by appropriately combining the multiple components disclosed in each of the embodiments described above. For example, some components may be removed from all the components shown in each embodiment. Furthermore, components from different embodiments may be combined as appropriate. [Explanation of symbols]

[0146] 1...Hard disk drive, 4...Disk, 8...Arm, 10...Suspension, 11...Slider, 20...Base plate, 30...Load beam, 32...Dimple, 40...Flexi, 41...Metal base, 42...Tang part, 43...Frame part, 44...Fixing part, 50...Wiring part, 70A, 70B...Limiter, 71...Root part, 73...Flat part, 75...Intermediate part, 90...Cover member, 411...Surface, 413...Surface, 440...Overlapping part, G2...Gap.

Claims

1. A flexible shaft that is superimposed on the road beam of a suspension for a hard disk drive, The metal base comprises a first surface facing the road beam and a second surface opposite to the first surface, The aforementioned metal base is The mounting section where the slider is installed, A fixing portion is provided on the tip side of the mounting portion in the longitudinal direction of the metal base and is fixed to the road beam, The metal base has a pair of limiters arranged in the width direction, Each of the pair of limiters includes a planar portion that faces the first or second surface with a gap between them in the thickness direction of the metal base. A flexi-shaft suspension for hard disk drives.

2. The pair of limiters is formed by a pair of first extensions extending from the mounting portion, The planar portion is, in the thickness direction, facing the first surface of the fixing portion. A flexure for a hard disk drive suspension according to claim 1.

3. Each of the pair of limiters further includes a first root portion connected to the mounting portion and a first intermediate portion between the first root portion and the planar portion. The flexure for a hard disk drive suspension according to claim 2.

4. The fixed portion is located in the width direction between the first intermediate portions of the pair of limiters. A flexisha for a hard disk drive suspension according to claim 3.

5. The pair of limiters is formed by a pair of second extensions extending from the fixed portion, The planar portion is facing the second surface of the mounting portion in the thickness direction. A flexure for a hard disk drive suspension according to claim 1.

6. Each of the pair of limiters further includes a second root portion connected to the fixed portion and a second intermediate portion connecting the second root portion and the planar portion. The flexure for a hard disk drive suspension according to claim 5.

7. The mounting portion further comprises a wiring portion disposed between the second surface and the flat surface of the mounting portion. A flexure for a hard disk drive suspension according to claim 6.

8. The metal base is located outside the mounting portion and further has a frame portion, The fixing portion is located between the mounting portion and the frame portion in the longitudinal direction. A flexure for a hard disk drive suspension according to claim 7.

9. The metal base is located outside the mounting portion and further has a frame portion, The frame portion is located between the mounting portion and the fixing portion in the longitudinal direction. The planar portion is further facing the second surface of the frame portion in the thickness direction. A flexure for a hard disk drive suspension according to claim 7.

10. The metal base is located outside the mounting portion and further has a frame portion, The pair of limiters is formed by a pair of first extensions extending from the mounting portion, The planar portion is facing the first surface of the frame portion in the thickness direction. A flexure for a hard disk drive suspension according to claim 1.

11. Each of the pair of limiters further includes a first root portion connected to the mounting portion and a first intermediate portion connecting the first root portion and the planar portion. A flexi-shaft for a hard disk drive suspension according to claim 10.

12. The fixing portion is located between the mounting portion and the frame portion in the longitudinal direction. The flexure for a hard disk drive suspension according to claim 11.

13. The frame portion is located between the mounting portion and the fixing portion in the longitudinal direction. The flexure for a hard disk drive suspension according to claim 11.

14. It further comprises a cover member made of a resin material and positioned on the flat portion, A flexi-shaft for a hard disk drive suspension according to any one of claims 1 to 13.

15. Road beam and, The road beam is superimposed on a flexure, The flexure comprises a metal base having a first surface facing the road beam and a second surface opposite to the first surface. The aforementioned metal base is The mounting section where the slider is installed, A fixing portion is provided on the tip side of the mounting portion in the longitudinal direction of the metal base and is fixed to the road beam, The metal base has a pair of limiters arranged in the width direction, Each of the pair of limiters includes a planar portion that faces the first or second surface with a gap between them in the thickness direction of the metal base. Suspension for hard disk drives.

16. The pair of limiters is formed by a pair of first extensions extending from the mounting portion, The planar portion is, in the thickness direction, facing the first surface of the fixing portion. The suspension for a hard disk drive according to claim 15.

17. The pair of limiters is formed by a pair of second extensions extending from the fixed portion, The planar portion is facing the second surface of the mounting portion in the thickness direction. The suspension for a hard disk drive according to claim 15.

18. The metal base is located outside the mounting portion and further has a frame portion, The pair of limiters is formed by a pair of first extensions extending from the mounting portion, The planar portion is facing the first surface of the frame portion in the thickness direction. The suspension for a hard disk drive according to claim 15.

19. It further comprises a cover member made of a resin material and positioned on the flat portion, A suspension for a hard disk drive according to any one of claims 15 to 18.

Images