Disk drive suspension

Abstract

According to one embodiment, a suspension (10) includes a load beam (20) having a recessed portion (50), and a bend (21) having a slider mounting portion (30). The recessed portion (50) has a convex surface (51) in contact with the slider mounting portion (30). The slider mounting portion (30) is swingably supported by the gimbal assembly member (40). The curvature radius (R) of the convex surface (51) is less than 0.15 mm. When the slider mounting portion (30) swings in the pitch direction, the bending pitch resistance (Fpr) acting on the contact portion (90) is 0.005 N or less. The phase delay of the fluctuation of the slider mounting portion (30) with respect to the rotating disk (12) in the pitch direction is 20 DEG or less.

Description

Technical Field

[0001] The invention relates to a disk drive suspension, which comprises a swingable slider mounting part, on which a slider is mounted. Background Art

[0002] For information processing devices such as personal computers, hard disk drives (HDDs) are used. The hard disk drive includes a disk that rotates around a spindle, a bracket that rotates around a pivot, and the like. The bracket includes an arm portion. The bracket rotates around the pivot by a positioning motor such as a voice coil motor.

[0003] A disk drive suspension (hereinafter referred to as suspension) is attached to the arm portion of the bracket. The suspension includes a load beam, a bending piece arranged along the load beam, etc. The slider is mounted on a slider mounting portion formed near the distal end of the bending piece. In this field, the slider mounting portion can be called a tongue.

[0004] The load beam, flexure, slider, etc. constitute the gimbal assembly. In the slider, an element for accessing, e.g., reading or writing data, is provided. When a disk drive is used, the element of the slider performs data access to the recording surface of the disk as the disk rotates.

[0005] For example, Japanese Patent No. 2014-22013A (Patent Document 1) and Japanese Patent No. 2020-140749A (Patent Document 2) describe examples of suspensions with slider mounting portions. In this type of suspension, the convex surface of the recessed portion contacts the slider mounting portion. The recessed portion is provided on a load beam. The slider mounting portion is elastically supported by a universal joint assembly such as a cantilever beam. The slider mounting portion swings around the convex surface of the recessed portion.

[0006] As the disk rotates, air flows between the front end of the slider and the rear end of the slider. As a result, an air bearing is formed. The term "front end" used in this specification refers to the end where air flows between the slider and the corresponding disk when the disk rotates. The "rear end" refers to the end where air flows out.

[0007] In order to adapt to the higher recording density of the magnetic disk, the distance between the slider and the magnetic disk tends to become smaller. When the magnetic disk rotates, the above-mentioned air bearing is formed. For example, when the air bearing is formed, the distance between the front end of the slider and the magnetic disk is 100nm. On the other hand, for example, the distance between the rear end of the slider and the magnetic disk is 10nm.

[0008] The recording surface of the disk appears to be flat, but in fact, fluctuations with an amplitude of about several microns may occur along the circumferential direction of the disk. The authors of the present invention carefully examined the flatness of the disk. They found that the fluctuations located around the outer circumference of the disk tend to be larger than the fluctuations located near the center clamp, which is closer to the rotation center of the disk. Here, please note that the slider must move in the pitch direction following the fluctuations of the disk.

[0009] The slider swings relative to the load beam around the convex surface of the concave portion as a fulcrum. In this specification, the behavior of the front part of the slider moving away from or toward the load beam in the longitudinal direction of the suspension is called pitch. The pitch angle is the angle with the reference position in the pitch direction. In this specification, the movement of the front part of the slider in the direction of movement closer to the load beam is called "movement in the positive pitch angle direction". The movement of the front part of the slider away from the load beam is called "movement in the negative pitch angle direction".

[0010] When the slider moves along the upward slope of the undulation on the disk, the slider moves along the disk surface in the direction of a negative pitch angle. When the slider moves along the downward slope of the undulation, the slider moves along the disk surface in the direction of a positive pitch angle.

[0011] The slider is tilted at a slightly positive pitch angle relative to the disk surface. The pitch angle is usually very small, such as 0.006°. For example, if the amplitude of the fluctuation is 3 to 6 μm, the slider needs to move while changing a relatively large angle in the pitch direction, such as ±0.03 to ±0.06°.

[0012] With the recent development of disk drives, the length of the suspension tends to be shortened. The load beam has a certain degree of angle in the pitch direction relative to the disk surface. The slider mounting portion is located at the far end of the load beam. The slider mounting portion moves relative to the load beam in the pitch direction of the recessed portion. As the length of the suspension is shortened, the angle change of the slider in the pitch direction becomes larger. For example, it is known that the angle change of the slider becomes larger when the length of the suspension approaches 6 mm.

[0013] If the slider cannot follow the fluctuations of the disk quickly enough, the slider may get too close to the surface of the disk. When the slider gets too close to the disk surface, friction between the slider and the disk or air bearing is known to occur, which may cause hot spots. In extreme cases, the slider may come into contact with the disk and scratch the disk or the slider.

[0014] The authors of the present invention have conducted intensive research and found that in some cases, the slider is too close to the disk at a location where the pitch angle changes significantly. The pitch angle changes significantly near the top of the fluctuation on the disk and near the bottom of the fluctuation. In order to avoid interference between the disk and the slider, the inventors have learned that the tracking performance of the slider to the fluctuation of the disk is important.

[0015] In this technical field, it is customary to assume that the slider mounting portion, such as a tongue, swings almost at a single point when in contact with the convex surface of the recessed portion. The contact between the convex surface of the recessed portion and the slider mounting portion corresponds to the contact between a spherical surface rolling on a plane and a flat surface. This contact is considered to be a Hertzian elastic contact. In the Hertzian elastic contact, the friction between the slider mounting portion (flat surface) and the convex surface of the recessed portion (sphere) is almost negligible. Therefore, it is not considered that the movement of the slider mounting portion is affected by the friction force with the convex surface.

[0016] An object of one embodiment of the present invention is to provide a suspension for a magnetic disk drive that can suppress interference between a rotating disk and a slider. Summary of the invention

[0017] As a result of the inventor's in-depth research, it was found that the contact portion between the convex surface of the concave portion and the slider mounting portion generates a force similar to the friction force, but in the opposite direction to the pitch direction. The inventor calls this force bending pitch resistance (Fpr). Fpr is the abbreviation of bending pitch resistance.

[0018] When the slider mounting portion swings above the convex surface of the recessed portion, a bending pitch resistance (Fpr) is generated at the contact portion between the slider mounting portion and the convex surface. In addition, it has been found that the bending pitch resistance (Fpr) may cause a phase delay in the slider when the slider mounting portion following the fluctuation of the disk swings. The behavior of the slider following the fluctuation of the disk was further studied. The results of the study showed that if the phase delay of the slider in the pitch direction relative to the fluctuation period is 20° or less, preferably 15° or less, the interference between the disk and the slider can be suppressed.

[0019] According to a first aspect, a disk drive suspension includes a load beam and a flexure disposed along the load beam, and includes a slider mounting portion, a slider mounted on the slider mounting portion. The suspension includes a recessed portion and a gimbal assembly component. The recessed portion is formed on the load beam and has a convex surface that contacts the slider mounting portion. The gimbal assembly component supports the slider mounting portion that contacts the convex surface so as to be swingable in at least one pitch direction relative to the load beam.

[0020] The radius of curvature of the convex surface is less than 0.15 mm and 0.04 mm, or greater, and the phase delay of the slider mounting portion in the pitch direction relative to the disk fluctuation is less than 20°. Preferably, the radius of curvature of the convex surface should be less than 0.10 mm (e.g., 0.095 mm), and the phase delay of the slider mounting portion is 15° or less. More preferably, the radius of curvature of the convex surface should be less than 0.085 mm.

[0021] According to a second aspect, a disk drive suspension also includes a load beam, a flexure, a recessed portion, and a gimbal assembly component. The suspension is formed to have a bending pitch resistance (Fpr) of 0.005N or less, and a slider mounting portion is phase-delayed by 20° or less in a pitch direction relative to a disk fluctuation. The bending pitch resistance (Fpr) acts on a contact portion between a convex surface of the recessed portion and the slider mounting portion.

[0022] In the suspension of the present embodiment, preferably, the bending pitch resistance (Fpr) should be 0.002N or less, and the phase delay of the slider mounting portion should be 10° or less. More preferably, the bending pitch resistance (Fpr) should be 0.001N or less, and the phase delay of the slider mounting portion should be 5° or less. In the suspension of the embodiment, the radius of curvature of the convex surface may be less than 0.10mm (e.g., 0.095mm).

[0023] According to the suspension of the present invention, it is possible to suppress the slider, which moves in the pitch direction while following the fluctuation of the rotating disk, from interfering with the magnetic disk.

[0024] Other objects and advantages of the present invention will be listed in the following description, and part will be obvious from the description, or can be understood through the practice of the present invention. The objects and advantages of the present invention can be realized and obtained through the tools and combinations particularly pointed out below. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate schematic embodiments of the invention and, together with the general description given above and the detailed description of the embodiments given below, serve to explain the principles of the invention.

[0026] Figure 1 is a plan view showing a portion of a suspension according to one embodiment.

[0027] Figure 2 is along Figure 1 A cross-sectional view of a portion of the suspension and the slider taken along line F2-F2.

[0028] Figure 3 is a cross-sectional view schematically showing an example of a disk drive.

[0029] Figure 4 is a side view schematically showing Figure 2 Part of the suspension, slider and disk are shown.

[0030] Figure 5 is a side view schematically showing that when the slider moves in the negative pitch angle direction, Figure 4 The slider shown in .

[0031] Figure 6is a side view schematically showing that when the slider moves in the positive pitch angle direction, Figure 4 The slider shown in .

[0032] Figure 7 Yes means Figure 4 Schematic diagram of the motion system of the suspension, slider, and disk.

[0033] Figure 8 is a diagram illustrating the position of the disk in the wave cycle and the phase delay of the slider.

[0034] Fig. 9 is a graph illustrating the relationship between the radius of curvature of the convex surface of the concave portion and the phase delay of the slider.

[0035] Fig.10 is a graph illustrating the relationship between bending pitch resistance (Fpr) and slider phase delay. DETAILED DESCRIPTION

[0036] Now, a suspension of a disk drive according to an embodiment will be described with reference to the accompanying drawings. Hereinafter, the disk drive suspension may be simply referred to as a suspension.

[0037] Figure 1 is a plan view of a portion of the suspension 10 . Figure 2 is along Figure 1 A cross-sectional view of a portion of the suspension 10 taken along line F2-F2. Figure 3 1 is a cross-sectional view schematically showing a disk drive 11 including a suspension 10. The disk drive 11 includes one or more disks 12. The disk drive 11 will be described later, and the suspension 10 will be described first.

[0038] The suspension 10 includes a load beam 20 and a bending piece 21 disposed along the load beam 20. The load beam 20 is made of a stainless steel plate and extends along the length of the suspension 10. Figure 1 The direction indicated by the double-headed arrow X1 is the longitudinal direction of the load beam 20, that is, the longitudinal direction of the suspension 10. The thickness of the load beam 20 is, for example, 20 to 40 μm, but is not limited to this range.

[0039] The flexure 21 includes a metal base 22 made of a thin stainless steel plate and a wiring portion 23 provided along the metal base 22. The thickness of the metal base 22 is, for example, 20 μm (12 to 25 μm).

[0040] like Figure 1As shown, the metal base 22 is fixed to the load beam 20 through a plurality of welding parts (e.g., a first welding part W1 and a second welding part W2). The wiring part 23 includes a base insulating layer, a plurality of conductors and a cover layer. The base insulating layer is made of an electrical insulating resin such as polyimide. The conductor is formed on the base insulating layer. The cover layer covers the conductor.

[0041] A slider mounting portion 30 is formed on a portion of the metal base 22. In the art, the slider mounting portion 30 may be referred to as a tongue in some cases. Figure 2 As shown, the slider mounting portion 30 has a first surface 30a and a second surface 30b. The first surface 30a is opposite to the load beam 20. The second surface 30b is located on the opposite side of the first surface 30a with respect to the thickness direction of the metal base 22.

[0042] On the second surface 30b of the slider mounting portion 30, a slider 31 is provided so as to interpose the wiring portion 23 therebetween. A portion of the slider 31 is fixed to the slider mounting portion 30 by an adhesive. The slider 31 includes a front side portion 31a and a rear side portion 31b with respect to the rotation direction of the magnetic disk 12. The "front side" used in this specification is a side where air flows between the magnetic disk 12 and the slider 31 when the magnetic disk 12 rotates. The expression "rear side" is a side where air flows out.

[0043] At the far end 32 of the rear side of the slider 31, a plurality of elements 33 are provided. These elements 33 can, for example, in an MR element, convert between magnetic signals and electrical signals. These elements 33 are used to access the recording surface of the magnetic disk 12, for example, to write or read data. A heater 34 can be provided near the elements 33. When the heater 34 is powered on, the rear side portion 31b is heated and expanded. Therefore, the distance h1 between the rear side portion 31b and the magnetic disk 12 can be further reduced (e.g., Figures 4 to 6 For example, the distance h1 can be reduced to 1 nm or less.

[0044] The distance h1 between the rear side portion 31b of the slider 31b and the magnetic disk 12 may also be referred to as the head-to-medium spacing (HMS) in some cases. The distance h1 is smaller than the distance h2 between the leading side portion 31a and the magnetic disk 12 (eg, Figures 4 to 6 More specifically, the distance h2 is, for example, 100 nm, and h1 is, for example, 10 nm.

[0045] like Figure 1As shown, the slider mounting portion 30 is elastically supported on the load beam 20 by the first arms 41 and 42 and the second arms 43 and 44. The first arms 41 and 42 and the second arms 43 and 44 are examples of the gimbal assembly component 40. The first arms 41 and 42 and the second arms 43 and 44 are part of the metal base 22. The gimbal assembly component 40 can take a variety of forms, depending on the design of the flexure 21. Therefore, the gimbal assembly component 40 is not limited to Figure 1 Those in the examples shown.

[0046] The slider mounting portion 30 and the universal joint assembly component 40 constitute a universal joint portion 45. The universal joint portion 45 of the present embodiment is a part of the flexure 21. Actuator elements 46 and 47 may be provided on the respective sides of the slider 31. The actuator elements 46 and 47 are each formed of a piezoelectric material, such as lead zirconate titanate (PZT). When a voltage is applied, the actuator elements 46 and 47 may rotate the rear side portion 31b of the slider 31 a small amount in the width direction of the slider 31.

[0047] The distal ends of the first arms 41 and 42 are each supported by the first weld W1 on the load beam 20. The proximal end portions 43a and 44a of the respective second arms 43 and 44 are fixed to the load beam 20 by the second weld W2. In other words, the slider mounting portion 30 is elastically supported so that the universal joint assembly component 40 can swing relative to the load beam 20.

[0048] Between the slider mounting portion 30 and the distal end portion 21a of the bending member 21, stoppers 48 and 49 may be provided. The stoppers 48 and 49 are both made of resin, such as polyimide. The stoppers 48 and 49 are used to prevent the slider mounting portion 30 from swinging excessively when an external impact is input to the suspension 10. According to the design of the bending member 21, the stoppers 48 and 49 may function as a part of the universal joint assembly component 40.

[0049] A recessed portion 50 is formed on the load beam 20. Figure 2 As shown, the recessed portion 50 has a convex surface 51 that protrudes toward the slider mounting portion 30 in a dome shape. The convex surface 51 is shaped like an arc having a radius of curvature R rotated about the vertical axis Y. The convex surface 51 is approximately circular in a plan view of the slider mounting portion 30. The arc of the radius of curvature R is not necessarily a perfect circle. In other words, the convex surface 51 has a shape similar to a part of a hemispherical surface. The vicinity of the top of the convex surface 51 contacts the first surface 30a of the slider mounting portion 30.

[0050] Figure 2 FIG. 4 shows a state in which the convex surface 51 of the concave portion 50 contacts the slider mounting portion 30. The slider mounting portion 30 is at least in the pitch direction ( Figure 2The slider mount 30 is swung in the direction indicated by the arrow P in two directions. Therefore, in the slider mount 30, displacement occurs at least longitudinally around the convex surface 51 as the center thereof. The slider mount 30 is supported on the load beam 20 by the gimbal assembly component 40, such as a cantilever beam and an arm. The slider mount 30 can swing at least in the pitch direction (vertical swing direction) and the roll direction (horizontal swing direction) relative to the load beam 20.

[0051] Figure 3 1 is a cross-sectional view schematically showing an example of a disk drive (HDD) 11. The disk drive 11 includes a disk 12 that rotates around a spindle, a housing 70 (only a portion of which is shown), a bracket 72 that can pivot around a pivot 71, a motor 73 for driving the bracket 72 for positioning, etc. The housing 70 is sealed by a cover. The suspension 10 is attached to the distal end of an arm portion 74 of the bracket 72.

[0052] When the carriage 72 is pivoted by the positioning motor 73, the suspension 10 moves in the radial direction of the magnetic disk 12. As a result, the slider 31 moves to a predetermined position on the magnetic disk 12. When the magnetic disk 12 rotates, air flows from the front side portion 31a to the rear side portion 31b of the slider 31. This air flow generates an air bearing 80 between the magnetic disk 12 and the slider 31.

[0053] Figure 4 The surface 12a of the magnetic disk 12, the slider 31 and the recessed portion 50 are schematically shown along an imaginary flat reference plane N. The slider mounting portion 30 contacts the convex surface 51 while being elastically supported by the gimbal assembly part 40. With this configuration, the slider mounting portion 30 and the convex surface 51 contact each other at the contact portion 90.

[0054] The slider mounting portion 30 moves around the center of curvature Z1 as if rolling on the convex surface 51 while contacting the convex surface 51 at the contact portion 90. At this time, the convex surface 51 and the slider mounting portion 30 are substantially in elastic contact between a plane and a sphere (Hertzian elastic contact). Therefore, there is no slippage at the contact portion, and loss due to friction is considered to be almost no problem.

[0055] However, in reality, a force similar to friction acts on the contact portion 90 between the slider mounting portion 30 and the convex surface 51. This force is the bending pitch resistance Fpr discovered by the author of the present invention. The bending pitch resistance Fpr can be determined by analysis, depending on the design of the flexure 21 (mainly the design of the universal joint portion 45).

[0056] Figure 5 The slider 31 is schematically shown following the upward slope of the wave motion. The surface 12a of the disk 12 is at a negative pitch angle θ1 relative to the reference plane N. Figure 5As shown in FIG. 1 , the slider 31 follows the undulation of the magnetic disk 12. Therefore, the contact portion 90 between the slider mounting portion 30 and the convex surface 51 moves from the reference line Y1 to the first direction P1. The slider mounting portion 30 rolls on the convex surface 51 without substantially slipping. At this time, in the contact portion 90, a bending pitch resistance Fpr is generated in the direction opposite to the direction in which the slider mounting portion 30 moves. The bending pitch resistance Fpr acts in the tangential direction of the convex surface 51.

[0057] The bending pitch resistance Fpr acts on the contact portion 90 as a moment of the curvature radius R. Therefore, a torque around the center of curvature Z1 acts on the slider mounting portion 30. The torque around the center of curvature Z1 is expressed as the product (Fpr×r) of the bending pitch resistance Fpr and the curvature radius R. Here, the larger the curvature radius R, the larger the torque. This torque applies resistance to the movement of the slider mounting portion 30 in the pitch direction.

[0058] Figure 6 The state in which the slider 31 follows the fluctuation of the positive pitch angle θ2 is schematically shown. The slider mounting portion 30 and the convex surface 51 contact each other at the contact portion 90. When the slider 31 follows the fluctuation of the positive pitch angle θ2, the contact portion 90 moves from the reference line Y1 to the second direction P2. The slider mounting portion 30 rolls on the convex surface 51 without substantial sliding. At this time, the bending pitch resistance Fpr in the opposite direction to the moving direction of the slider mounting portion 30 acts on the contact portion 90 along the tangent direction of the convex surface 51.

[0059] Figure 7 3 is a diagram schematically showing a motion system including a slider 31. Figure 7 In the formula to be provided below, k1 represents the stiffness in the pitch direction (pitch stiffness) [Nm / rad] of the slider surface 31c facing the air bearing 80. Symbol k2 represents the pitch stiffness [Nm / rad] of the universal joint portion 45. Symbol C represents the viscous damping coefficient between the slider surface 31c facing the air bearing 80 and the universal joint portion 45. Symbol ζ represents the viscous damping ratio. Symbol θ is the pitch angle [rad], "a" represents the input amplitude [rad], Fpr represents the bending pitch resistance [N], R represents the curvature radius R [m], and ω represents the circumferential vibration frequency [rad / s]. Symbol I represents the inertia of the slider 31 including the slider mounting portion 30. Note that for I, in order to simplify the calculation, only the inertia of the slider 31 is considered.

[0060] When the force vibration input of θ0 is the fluctuation of the disk 12, the motion equation is expressed as:

[0061] I×θ"=-k1×(θ-a×sinωt)-C×θ'-k2×θ-R×Fpr

[0062] When this equation is transformed, the following formula 1 is obtained:

[0063] θ"+C / I×θ'+(k1+k2) / I×θ=a×k1 / I×sinωt-R×Fpr / I...Formula 1

[0064] Here, when

[0065]

[0066] The following formula is obtained:

[0067] (k1+k2) / I=ω02,C / I=2×ζ×ω0

[0068] Therefore, Formula 1 can be expressed as:

[0069] θ"+2×ζ×ω0×θ'+ω02×θ=a×k1 / I×sinωt-R×Fpr / I...Formula 2

[0070] The steady-state response of the equation of motion: θp = U × sinωt + V × cosωt can be expressed as follows:

[0071] Formula 3 to Formula 8 express.

[0072]

[0073] θp=U×sinωt+V×cosωt=A×sin(ωt-δ)Formula 5

[0074]

[0075] δ=tan-1(-V / U) Formula 7

[0076] Gain=A / aFormula 8

[0077] The response of the slider pitch to the disk fluctuation can be calculated by using Formula 3 to Formula 8. When ζ=0, the following formula can be obtained.

[0078]

[0079] From the formula for the case without viscous damping, the following can be found.

[0080] (1) When there is a bending pitch resistance Fpr, a phase delay δ occurs regardless of the frequency.

[0081] (2) The parameters of the phase delay δ are the radius of curvature R of the concave convex surface, the bending pitch resistance Fpr, the input amplitude a and the pitch stiffness k1 of the air bearing.

[0082] (3) In particular, when the magnetic disk wobble is 10 μm or less, the input amplitude a is minimum, so it can be inferred that the phase delay increases.

[0083] As described above, the bending pitch resistance Fpr generates only frictional force on the contact portion 90. Therefore, a phase delay is caused in the slider mounting portion 30, which moves in the pitch direction while following the fluctuation of the magnetic disk 12. The term "phase delay" used here means the position delay within one cycle when one cycle is 360° relative to a phenomenon that occurs periodically, such as the fluctuation of the rotating disk 12. In other words, it is the phase difference between the fluctuation cycle of the magnetic disk 12 and the cycle in which the slider 31 moves in the pitch direction.

[0084] Figure 8 The relationship between the position of the disk 12 in the undulation cycle and the pitch angle of the slider 31 is schematically shown. Figure 8 The phase delay (represented by the solid line L1 in Figure 8 (indicated by the dotted line L2 in FIG. 1 ). When a phase delay occurs in the slider 31 relative to the fluctuation of the magnetic disk 12, the subsequent movement of the slider 31 is delayed relative to the fluctuation. If the phase delay of the slider becomes large, the slider 31 and the magnetic disk 12 may interfere with each other.

[0085] The authors of the present invention have conducted in-depth research and found that in the position where the pitch angle of the fluctuation changes greatly, the excessive proximity of the slider and the disk will cause interference. The location where the fluctuation pitch angle changes greatly is located near the top of the peak of the disk fluctuation and near the bottom of the disk fluctuation. The slider follows the fluctuation of the rotating disk. Here, in order to suppress the interference between the disk and the slider, it is further found that it is effective to reduce the phase delay of the slider in the pitch direction to 20° or less, preferably 15° or less. Therefore, in order to prevent interference between the disk and the slider, it is recommended that the phase delay of the slider relative to the fluctuation period should be 20° or less, preferably 15° or less.

[0086] Fig. 9 : represents the relationship between the curvature radius R of the convex surface 51 and the phase delay of the slider 31. The parameters here are as follows.

[0087] I=3.15E-14[kg m 2 ], a=5.24E-4[rad](approximate value 0.03deg), R=2.5E-4[m]

[0088] (0.25mm), k1=8.0E-3[Nm / rad], k2=7.2E-6[Nm / rad], Fpr=0.01[N] (approximately 1gf), ζ=0.02

[0089] When the curvature radius R of the convex surface 51 is less than 0.15 mm, the phase delay can be less than 20°. However, due to the limitation of the mold used to form the concave portion 50, it is actually difficult to make the curvature radius R less than 0.04 mm. Therefore, the curvature radius R should be set to be less than 0.15 mm and greater than 0.04 mm. The height h3 of the concave portion (e.g. Figure 4 As shown), for example from 0.04 mm to 0.07 mm, but may be other heights.

[0090] When the curvature radius R of the convex surface 51 is less than 0.10 mm, the phase delay of the slider 31 can be less than 15°. Therefore, the curvature radius R less than 0.10 mm is more effective in suppressing interference with the magnetic disk. When the curvature radius R of the convex surface 51 is less than 0.085 mm, the phase delay can be reduced to nearly 10°.

[0091] Fig.10 is a graph illustrating the relationship between the bending pitch resistance (Fpr) and the phase delay of the slider. When the bending pitch resistance (Fpr) is 0.005N or less, the phase delay of the slider following the disk fluctuation can be reduced to 20° or less. More preferably, the bending pitch resistance (Fpr) should be set to 0.002N or less, so that the phase delay of the slider can reach 10° or less.

[0092] Preferably, the bending pitch resistance (Fpr) should be 0.001 N or less, so the phase delay of the slider can be 5° or less. In a suspension having a bending pitch resistance (Fpr) of 0.005 N or less, the curvature radius R of the convex surface 51 can be less than 0.10 mm.

[0093] In the process of implementing the present invention, it is self-evident that the various components of the suspension can be changed in many ways, including the specific mode, that is, the shape and position of the load beam, the flexure, the slider and the recessed portion. The disk drive is not limited to the above embodiment, but can take many forms as needed.

[0094] Other advantages and modifications will readily occur to those skilled in the art. Therefore, the present invention in its broader aspects is not limited to the specific details and representative embodiments shown and described herein. Therefore, various modifications may be made without departing from the spirit or scope of the general inventive concept defined by the appended claims and their equivalents.

Claims

1. A disk drive suspension (10), characterized in that: include, a load beam (20); a bending member (21) disposed along the load beam (20) and comprising a slider mounting portion (30) on which a slider (31) is mounted; a recessed portion (50) formed on the load beam (20) and including a convex surface (51) in contact with the slider mounting portion (30); A gimbal assembly component (40) supports the slider mounting portion (30) in contact with the convex surface (51) so as to be able to swing in at least one pitch direction, in, The curvature radius (R) of the convex surface (51) is less than 0.15 mm and 0.04 mm, or greater, and the phase delay of the slider mounting portion (30) in the pitch direction relative to the fluctuation of a rotating disk is 20 degrees or less.

2. The suspension (10) according to claim 1, characterized in that The curvature radius (R) of the convex surface (51) is less than 0.10 mm, and The phase delay of the slider mounting portion (30) is 15° or less.

3. The suspension (10) according to claim 1, characterized in that The curvature radius (R) of the convex surface (51) is less than 0.085 mm, and The phase delay of the slider mounting portion (30) is 15° or less.

4. A disk drive suspension (10), characterized in that: include: a load beam (20); a bending member (21) disposed along the load beam (20) and comprising a slider mounting portion (30) on which a slider (31) is mounted; a recessed portion (50) formed on the load beam (20) and including a convex surface (51) in contact with the slider mounting portion (30); A gimbal assembly component (40) supports a slider mounting portion (30) in contact with the convex surface (51) so as to be able to swing in at least one pitch direction; in, When the slider mounting portion (30) moves in the pitch direction, the bending pitch resistance (Fpr) acting on the contact portion between the slider mounting portion (30) and the convex surface (51) is 0.005N or less, and the phase delay of the slider mounting portion (30) in the pitch direction relative to the fluctuation of a rotating disk is 20° or less.

5. The suspension (10) according to claim 4, characterized in that The bending pitch resistance (Fpr) is 0.002N or less, The phase delay of the slider mounting portion (30) is 10° or less.

6. The suspension (10) according to claim 4, characterized in that The bending pitch resistance (Fpr) is 0.001N or less; and The phase delay of the slider mounting portion (30) is 5° or less.

7. The suspension (10) according to claim 4, characterized in that The curvature radius (R) of the convex surface (51) is less than 0.10 mm.

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