JPH11345474A - Magnetic disk device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a reliable magnetic disk device by preventing damages to a magnetic disk, an actuator, etc., when an impact is received. SOLUTION: A ramp load mechanism supporting a magnetic head 40 to a position parting from the magnetic disk through a suspension 38 when the head actuator 22 is moved to an unoperated position is provided in the case of the magnetic disk device. The ramp load mechanism is provided with a ramp provided being off to the outside of the magnetic disk 16 and a tab 42 provided eccentrically in the direction parting from the center of the magnetic disk for the central axis C of the suspension 38 on the tip of the suspension 38. When the head actuator 22 is moved to the unoperated position, the tab 42 runs onto the ramp 70. The head actuator 22 is formed to a shape not overlapping the magnetic disk in the unoperated position.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a magnetic disk drive, and more particularly to a magnetic disk drive having a ramp load mechanism.

[0002]

2. Description of the Related Art In recent years, magnetic disks have been widely used as large-capacity memory devices in electronic devices such as personal computers. Generally, a magnetic disk device includes a magnetic disk disposed in a case, a spindle motor for supporting and rotating the magnetic disk, a head actuator for supporting a magnetic head, a voice coil motor for driving the head actuator, and a substrate. And a unit.

[0003] The head actuator includes a bearing attached to a case, a plurality of arms extending from the bearing, and a suspension extending from each arm.
The magnetic head is attached to the extension end of the suspension.

In recent years, portable small personal computers have become widespread, and magnetic disk devices mounted on such personal computers are required to have improved reliability against shocks and the like when carried.

Therefore, in recent years, a mechanism provided with a ramp load mechanism has been provided as a mechanism for holding the magnetic head when the magnetic disk drive is not operating. This ramp loading mechanism includes a tab extending from the tip of the suspension along the center axis of the suspension, and a ramp arranged so that a part thereof overlaps the outer periphery of the magnetic disk. Then, when the magnetic disk drive shifts to the non-operation state, when the head actuator is rotated to the outer periphery of the magnetic disk, the tab of the suspension rides on the ramp, and the magnetic head is held at a position separated from the surface of the magnetic disk. You. This prevents collision between the magnetic head and the magnetic disk when receiving a shock.

[0006]

However, according to the magnetic disk drive having the above structure, the head actuator is loaded on the ramp, that is, the tab rides on the ramp and the magnetic head is separated from the magnetic disk display surface. In this state, a part of the head actuator overlaps with the magnetic disk. Further, as described above, the lamp itself is partially arranged so as to overlap the magnetic disk.

Therefore, when the magnetic disk vibrates along its axial direction due to an impact or the like, the surface of the magnetic disk may come into contact with the head actuator or the lamp, and the disk surface, the actuator or the lamp may be damaged. Therefore, the reliability of the magnetic disk device against an impact becomes a problem.

In recent years, in order to reduce noise and increase TPI, a spindle motor using a fluid bearing has been used as a spindle motor for supporting and rotating a magnetic disk. However, such a spindle motor usually does not include a thrust bearing, and the rotor has a certain gap (for example, 0.1 mm) in its axial direction. Therefore, when the magnetic disk drive is not operating,
When an external impact acts, the rotor vibrates in the axial direction together with the magnetic disk. Therefore, also in this case, the magnetic disk surface contacts the head actuator or the ramp,
Damage to the disk surface, actuator, or ramp may occur.

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and an object of the present invention is to provide a highly reliable magnetic disk device by preventing damage to a magnetic disk, an actuator, and the like due to an impact.

[0010]

In order to achieve the above object, a magnetic disk drive according to the present invention comprises a magnetic disk, driving means for supporting and rotating the magnetic disk, and information transfer to the magnetic disk. A magnetic head for performing recording and reproduction, a plate-like arm rotatably supported,
A plate-shaped suspension extending from the distal end of the arm and having the magnetic head attached to the distal end, a head actuator movably supporting the magnetic head with respect to the magnetic disk, A ramp load mechanism that supports the head actuator at a non-operation position where the magnetic head is separated from the magnetic disk, wherein the head actuator overlaps the magnetic disk in the central axis direction of the magnetic disk at the non-operation position. It is characterized in that it is formed in a shape that does not become difficult.

A magnetic disk drive according to the present invention comprises: a magnetic disk; a driving means for supporting and rotating the magnetic disk; a magnetic head for recording and reproducing information on and from the magnetic disk; And a plate-like suspension extending from the tip of the arm and having the tip attached to the magnetic head, and having the magnetic head with respect to the magnetic disk. A head actuator movably supported; and a ramp load mechanism for supporting the head actuator at a non-operation position where the magnetic head is separated from the magnetic disk.

[0012] The ramp load mechanism is provided such that a ramp provided outside the magnetic disk is eccentric to a tip of the suspension in a direction away from a center of the magnetic disk with respect to a center axis of the suspension. An engagement portion that rides on the ramp when the magnetic head moves to the outer peripheral portion of the magnetic disk, wherein the head actuator is arranged in the inoperative position in a direction of a central axis of the magnetic disk. It is characterized in that it is formed in a shape that does not overlap with.

According to the magnetic disk drive of the present invention, the suspension of the head actuator has a predetermined angle in a direction away from the center of the magnetic disk with respect to a line passing through the center of rotation of the head actuator and the magnetic head. It is characterized in that it has a central axis that extends obliquely. Preferably, the predetermined angle is set in a range of 2 degrees to 10 degrees.

Further, according to the magnetic disk drive of the present invention, the drive means includes: a rotatable rotor supporting the magnetic disk; and a stator rotatably supporting the rotor via a fluid bearing. It is characterized by having.

According to the magnetic disk drive configured as described above, when not operating, the magnetic head is held at a position separated from the surface of the magnetic disk by the ramp load mechanism. In this case, the head actuator is formed in a shape that does not overlap with the magnetic disk in a direction parallel to the center axis of the magnetic disk. Therefore, even when the magnetic disk device and the head actuator vibrate in the direction of the center axis of the magnetic disk due to an impact or the like acting on the magnetic disk device,
The head actuator does not come into contact with the surface of the magnetic disk, so that these damages can be prevented.

In particular, when a spindle motor having a fluid bearing is used as the driving means, the magnetic disk also vibrates in the central axis direction due to the vibration of the spindle motor in the central axis direction. The contact between the disk surface and the head actuator can be prevented, and the magnetic disk and the head actuator can be prevented from being damaged.

Further, according to the present invention, since the ramp of the ramp loading mechanism is provided at a position separated from the magnetic disk, even if the magnetic disk vibrates in the direction of its central axis, the ramp is applied to the surface of the magnetic disk. Without such contact, these damages can be prevented. In this case, the engagement portion provided on the suspension side is eccentrically located from the center axis of the suspension, so that when the head actuator moves to the non-operation position, it can smoothly engage with the ramp. As described above, according to the present invention, it is possible to provide a magnetic disk device with improved impact resistance and high reliability.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to a hard disk drive (hereinafter referred to as an HDD) will be described in detail with reference to the drawings. As shown in FIG. 1, the HDD has a rectangular box-shaped case 12 with an open upper surface, and a top cover (not shown) that is screwed to the case with a plurality of screws to close an upper end opening of the case. .

In the case 12, three magnetic disks 16 as a magnetic recording medium, a spindle motor 18 as a driving means for supporting and rotating the magnetic disks,
A plurality of magnetic heads for writing and reading information to and from a magnetic disk, a head actuator 22 that movably supports these magnetic heads with respect to the magnetic disk 16, and a voice coil motor (hereinafter, referred to as a rotating and positioning head actuator). 24, a ramp load mechanism 25 for holding the magnetic head at a position separated from the magnetic disk when the magnetic head moves to the outermost periphery of the magnetic disk, and a substrate unit 21 having a head IC and the like. .

On the outer surface of the bottom wall of the case 12, a spindle motor 18, a VCM 2
4, and a printed circuit board (not shown) for controlling the operation of the magnetic head are screwed.

As shown in FIGS. 1 and 2, the spindle motor 18 includes a motor bracket 50 mounted on the bottom wall of the case 12, and a hub 52 as a rotor rotatably supported by the motor bracket. ing. A hollow support cylinder 54 is erected at the center of the motor bracket 50, and an annular stator 53 having a core and a coil is mounted on the outer periphery of the support cylinder. Also,
A cylindrical sleeve 55 is coaxially fixed to the inner periphery of the support cylinder 54.

The hub 52 includes a cylindrical hub body 56,
A pivot 58 coaxially located inside the hub body and an annular upper end wall 60 connecting the upper ends of the hub body 56 and the pivot 58 are integrally provided. A flange 61 is provided on the outer periphery of the intermediate portion of the hub body 56, and a screw hole for screwing a clamp ring described later is formed in the center of the upper end wall 60.

The hub 52 is rotatably supported by the motor bracket 50 with the pivot 58 inserted coaxially into the sleeve 55. In this case, a number of grooves for generating a dynamic pressure, for example, a herringbone-shaped groove are formed on one of the outer peripheral surface of the pivot 58 and the inner peripheral surface of the sleeve 55. A fluid bearing 62 is formed between the bearing 55 and the inner peripheral surface of the bearing 55. A thrust bearing for supporting the load in the thrust direction, that is, the axial direction of the pivot 58 is not provided. Instead, an annular hard stopper 64 is fixed to the outer periphery of the lower end of the pivot 58.

An annular permanent magnet 65 is coaxially fixed to the inner peripheral surface of the hub body 56 and faces the stator 55. Then, by energizing the coil of the stator 53, a driving torque is generated and the hub 52 is driven to rotate.

The magnetic disk 16 has a diameter of 65 mm (2.
5 inches) and has a magnetic recording layer on the upper and lower surfaces. The three magnetic disks 16 are fitted on the outer peripheral surface of the hub main body in a state where the hub main body 56 of the spindle motor 18 is inserted through the inner holes thereof, and are stacked on the flange 61 along the axial direction of the hub 52. Have been. A pair of spacer rings 66 are fitted on the outer periphery of the hub main body 52 and are stacked so as to be sandwiched between adjacent magnetic disks 16.

The upper end wall 60 of the hub 52 has one screw 6
7, the clamp ring 17 is screwed and fixed. The outer peripheral portion of the clamp ring 17 abuts on the upper surface of the central portion of the upper magnetic disk 16, and connects the three magnetic disks and the two spacer rings 66 to the flange 61 of the hub 52.
Pressing toward. Thereby, the magnetic disk 1
The spacer 6 and the spacer ring 66 are sandwiched between the flange 61 and the clamp ring 17, and are fixed and held to the hub 52 in a state of being in close contact with each other. Then, by driving the spindle motor 18, the three magnetic disks 1
6 is rotated integrally with the hub 52 at a predetermined speed.

As shown in FIGS. 1 and 3, the head actuator 22 has a bearing assembly 26 fixed on the bottom wall of the case 12. The bearing assembly 26 has a pivot 27 that stands vertically to the bottom wall of the case 12 and a cylindrical hub 28 that is rotatably supported on the pivot via a pair of bearings. . The head actuator 22 has six arms 32 attached to the hub 28.
And a plurality of spacer rings, and a magnetic head assembly 36 supported by each arm.

The arm 32 is formed of a stainless steel material such as SUS304 into a flat plate having a thickness of about 250 μm, and has a through hole (not shown) formed at one end, that is, at the base end. .

Each magnetic head assembly 36 includes an elongated plate-like suspension 38 that can be elastically deformed, and a magnetic head 40 fixed to the tip of the suspension.
The suspension 38 is formed of a leaf spring, and its base end is fixed to the distal end of the arm 32 by spot welding or bonding, and extends from the arm.

Each magnetic head 40 has a substantially rectangular slider and a recording / reproducing MR (magnetoresistive) head formed on the slider, and has a gimbal portion (not shown) provided at the tip of a suspension 38. Fixed.

The fixed arm of the magnetic head assembly 36 is fitted on the outer periphery of the hub in a stacked state by inserting the hub 28 of the bearing assembly through a through hole at the base end. The spacer ring is fitted on the outer periphery of the hub 28 while being sandwiched between the arms. Thus, the six arms 32 are located parallel to each other at a predetermined interval and extend from the hub 28 in the same direction.

In the head actuator 22 described above, the magnetic head 40 is located outside the magnetic disk 16 in FIG.
When the arm 32 and the suspension 38 are rotated to the inoperative position, the arms 32 and the suspension 38 do not overlap with the magnetic disk 16.
That is, it is formed so as not to overlap with the magnetic disk in the axial direction of the magnetic disk.

More specifically, as shown in FIG. 3, each suspension 38 has its center axis C having a reference line B passing through the center of the bearing assembly 26, which is the center of rotation of the head actuator 22, and the magnetic head 40. Is fixed to the arm 32 while being inclined by a predetermined angle θ in a direction away from the center of the magnetic disk 16. That is, the suspension 38 is arranged with an inline angle θ with respect to the arm 32. This predetermined angle θ is desirably set to 2 degrees to 10 degrees.

In each arm 32, an arc-shaped concave portion 32a corresponding to the outer peripheral edge of the magnetic disk is formed on the side edge located on the center side of the magnetic disk 16.
Each suspension 38 is integrally provided with a tab (projection) 42 extending from the tip. The tab 42 functions as an engaging portion that constitutes a part of a ramp load mechanism 25 described later, extends in parallel with the central axis C of the suspension 38, and has the center of the magnetic disk 16 with respect to the central axis C. It is provided eccentrically by a predetermined distance d in the direction away from.

On the other hand, as shown in FIGS. 1 and 3, the head actuator 22 has a support frame 44 extending from one spacer ring in the direction opposite to the arm 32. It supports a voice coil 45 constituting a part. The support frame 44 is formed integrally with the outer periphery of the voice coil 45 by a synthetic resin, and is fixed to a spacer ring via a mounting portion 80. Note that a connector 81 having a terminal connected to the voice coil 45 is formed integrally with the mounting portion 80.

As shown in FIGS. 1 and 4, each magnetic disk 16 is located between two arms 32 when the head actuator 22 configured as described above is incorporated in the case 12. The magnetic head 40 attached to the suspension 38 faces the upper and lower surfaces of the magnetic disk 16 respectively, and holds the magnetic disk 16 from both sides. Each magnetic head 40
A predetermined head load is applied toward the surface of the magnetic disk by the spring force of the suspension 38.

As shown in FIG. 1, a voice coil 45 fixed to a support frame 44 of the head actuator 22 is provided.
Are located between a pair of yokes 48 fixed on the case 12 and constitute the VCM 24 together with these yokes and the magnet 46 fixed to one of the yokes. And
By energizing the voice coil 45, the head actuator 22 rotates, and the magnetic head 40 is moved and positioned on a desired track of the magnetic disk 16.

As shown in FIG. 1, the board unit 21
It has a plurality of electronic components (not shown), connectors, and the like, and is connected to the head actuator 22 via a flexible printed circuit board (not shown). Case 1
2, a latch mechanism (not shown) is provided near the VCM 24 to lock the head actuator when the HDD is not operated and receives an impact.

As shown in FIGS. 1, 4 and 5, the ramp loading mechanism 25 has a ramp 70 provided on the bottom wall of the case 12 and located outside the magnetic disk 16. The ramp 70 has six guide surfaces 72 for guiding the tabs 42 provided on the six suspensions 38 of the head actuator 22, respectively. These guide surfaces 72 are arranged in accordance with the levels of the corresponding suspensions 38, and extend along the radial direction of the magnetic disk 16 to near the outer peripheral edge of the magnetic disk 16.
Are arranged on the movement path of the tab 42 provided in the first position.

Each guide surface 72 has a first inclined surface 72a for loading and unloading the magnetic head 40 on and from the magnetic disk 16, and a flat portion 72b extending parallel to the surface of the magnetic disk following the first inclined surface. When the suspension 38 provided on the flat portion moves to the non-operation position, the tab 42
And a second inclined surface 72d located between the flat portion and the recess.

According to the HDD configured as described above,
As shown in FIG. 1, during normal operation, by rotating the head actuator 22 by the VCM 24, the magnetic head 40 is moved onto a desired track of the magnetic disk 16 to record or reproduce information on the magnetic disk. I do.

As shown in FIG. 5, when the HDD is shifted to the non-operation state, when the head actuator 22 is rotated by the VCM 24 toward the non-operation position indicated by the solid line, the magnetic head 40 is moved to the magnetic disk 16. Move from the inner circumference side to the outermost circumference. When the magnetic head 40 moves to the vicinity of the outer peripheral edge of the magnetic disk 16, the tab 42 extending from each suspension 38 is moved to the magnetic disk 1.
6 project outwardly from the outer peripheral edge and ride on the corresponding guide surfaces 72 of the ramps 70 respectively. At this time, each tab 4
2 moves in a direction away from the surface of the magnetic disk 16 along the first guide surface 72a and rides on the flat portion 72b. Then, when the head actuator 22 reaches the non-operation position, each tab 42 is in the recess 7 of the guide surface 72.
It is moved and held in 2c. Thus, each magnetic head 40 of the head actuator 22 is held at a predetermined position separated from the surface of the magnetic disk. When the head actuator 22 is held at the non-operation position, each arm 32 and the suspension 38 are positioned off the outer peripheral edge of the magnetic disk without overlapping the magnetic disk in the axial direction of the magnetic disk.

On the other hand, when the HDD is operated again, the head actuator 22 is rotated while the magnetic disk 16 is rotated.
Is rotated from the inoperative position toward the inner peripheral side of the magnetic disk. Then, the tab 42 of each suspension 38
A flat portion 72b extends from the recess 72c along the second inclined surface 72d.
It moves upward and further slides down the first inclined surface 72a. In response, each magnetic head 40 also moves and is loaded on the surface of the magnetic disk 16.

According to the HDD configured as described above,
When not operating, the ramp load mechanism 25 causes the magnetic head 4
0 can be held at a position separated from the magnetic disk 16, and even when an external impact acts on the HDD, the displacement of the magnetic head, the collision between the magnetic head and the magnetic disk, and the like can be prevented.

Further, according to the HDD, the ramp 70 of the ramp loading mechanism 25 is provided outside the magnetic disk 16 without overlapping with the magnetic disk 16, so that the magnetic disk 16 is moved to its center by an impact or the like. Even when vibrating along the axial direction, the magnetic disk and the ramp 70
Does not interfere with each other, and damage to the magnetic disk can be prevented. At this time, since the tab 42 provided on the suspension 38 is displaced from the center axis of the suspension in a direction away from the center of the magnetic disk, the ramp 70 is provided outside the magnetic disk. The tab 42 can engage the ramp 70 before the magnetic head 40 moves away from the outer periphery of the magnetic disk. Therefore, loading and unloading can be performed smoothly without damaging the magnetic head 40.

Further, according to the HDD, the head actuator 22 moves the magnetic disk 1 in the non-operation position.
6 so as to be positioned outside the magnetic disk without overlapping. Therefore, even when the magnetic disk 16 or the head actuator 22 vibrates along the center axis direction of the magnetic disk due to an impact or the like, interference between the magnetic disk and the head actuator 22 is prevented,
Damage to the magnetic disk and the head actuator can be prevented.

At this time, the suspension 38 of the head actuator 22 is provided at an in-line angle θ with respect to the arm 32, and the arm and the suspension are formed along the outer peripheral edge of the magnetic disk 16.
Therefore, the head actuator can be moved to a position that does not overlap with the magnetic disk without greatly increasing the rotation angle of the head actuator 22, and a ramp load can be realized without reducing the space utilization efficiency in the case 12. It becomes possible.

According to the HDD, the fluid bearing 62
By using the spindle motor having the above, it is possible to reduce noise, increase the TPI, improve the shock resistance during non-operation, and the like. In the case of a spindle motor using the above-mentioned fluid bearing, a hard stopper 64 is usually provided without a thrust bearing and a gap of, for example, about 0.1 mm in the thrust direction. Therefore, when a shock is applied along the axial direction of the magnetic disk during non-operation, the hub of the spindle motor vibrates with the magnetic disk in the thrust direction by the gap. However, as described above, in the non-operating state, the head actuator 22 and the ramp 70 are located off the magnetic disk 16, so that the magnetic disk does not come into contact with the head actuator 22 and the ramp 70, and these Damage can be prevented.

As described above, it is possible to realize a highly reliable magnetic disk device having improved impact resistance. Further, according to the HDD having the above-described configuration, the magnetic disk can be incorporated by assembling the head actuator 22, the ramp mechanism, and the like to the case, and then moving the head actuator to the non-operation position. Accordingly, contamination and damage to the magnetic disk during assembly can be reduced, and the production yield can be improved.

The present invention is not limited to the above-described embodiment, but can be variously modified within the scope of the present invention. For example, the number of magnetic disks, the number of corresponding magnetic heads, the number of arms, and the like can be increased or decreased as necessary, and the number of ramps of the ramp loading mechanism increases as the number of magnetic heads increases.

[0051]

As described above in detail, according to the present invention, the interference between the magnetic disk and the head actuator and the ramp load mechanism during non-operation is prevented, and the highly reliable magnetic disk with improved shock resistance is provided. An apparatus can be provided.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view showing an HDD according to an embodiment of the present invention.

FIG. 2 is a sectional view showing a spindle motor provided in the HDD.

FIG. 3 is a plan view of the head actuator.

FIG. 4 is a diagram schematically showing an arrangement relationship between the head actuator and a lamp.

FIG. 5 is a plan view of the HDD in a state where the head actuator has moved to a non-operation position.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 12 ... Case 16 ... Magnetic disk 18 ... Spindle motor 22 ... Head actuator 24 ... Voice coil motor 25 ... Ramp loading mechanism 26 ... Bearing assembly 32 ... Arm 38 ... Suspension 40 ... Magnetic head 42 ... Tab 62 ... Fluid bearing 70 ... Ramp 72… Guide surface

Claims (7)

[Claims] A magnetic disk; a driving means for supporting and rotating the magnetic disk; a magnetic head for recording and reproducing information on and from the magnetic disk; a plate-like arm rotatably supported; A plate-shaped suspension extending from the distal end of the arm and having the magnetic head attached to the distal end thereof, and a head actuator movably supporting the magnetic head with respect to the magnetic disk; A ramp load mechanism that supports the head actuator at a non-operation position in which the magnetic head is separated from the magnetic disk, wherein the head actuator is in a non-operation position in a direction parallel to a central axis of the magnetic disk. A magnetic disk drive, wherein the magnetic disk drive is formed so as not to overlap the magnetic disk. 2. A magnetic disk, a driving means for supporting and rotating the magnetic disk, a magnetic head for recording and reproducing information on and from the magnetic disk, and a plate-like arm rotatably supported. A plate-shaped suspension extending from the distal end of the arm and having the magnetic head attached to the distal end thereof, and a head actuator movably supporting the magnetic head with respect to the magnetic disk; A ramp loading mechanism that supports the head actuator at a non-operating position where the magnetic head is separated from the magnetic disk; the ramp loading mechanism includes a ramp provided outside the magnetic disk and the suspension. Eccentric to the center of the suspension, away from the center of the magnetic disk And an engaging portion that rides on the ramp when the magnetic head moves to the outer peripheral portion of the magnetic disk.The head actuator is parallel to a central axis of the magnetic disk in the non-operation position. A magnetic disk drive characterized in that it is formed in a shape that does not overlap with the magnetic disk in the direction. 3. The suspension of the head actuator has a center axis inclined at a predetermined angle in a direction away from the center of the magnetic disk with respect to a line passing through the rotation center of the head actuator and the magnetic head. 3. The magnetic disk drive according to claim 1, wherein: 4. The magnetic disk drive according to claim 3, wherein said engaging portion includes a projection extending from a tip of said suspension substantially parallel to a central axis of said suspension. 5. The magnetic disk drive according to claim 3, wherein the predetermined angle is set in a range of 2 degrees to 10 degrees. 6. The arm of the head actuator is formed at a side edge on the center side of the magnetic disk and has a recess along a peripheral edge of the magnetic disk. Any one of claims 1 to 5
A magnetic disk drive according to the item. 7. The apparatus according to claim 1, wherein said driving means comprises a rotatable rotor supporting said magnetic disk, and a stator rotatably supporting said rotor via a fluid bearing. 7. The magnetic disk drive according to any one of items 6 to 6.