JP2002124076A - Magnetic disk device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To achieve miniaturization and thinning by obtaining rotational accuracy and rotating performance equal to/higher than those of a ball bearing using the oil-containing bearing of a normal structure, and reducing costs. SOLUTION: Stoppers 110 and 111 are disposed in the opposing surfaces of a magnetic disk 100 having a spindle motor rotating part provided with a magnetic disk 100, a shaft 112 and a hub 114 in a side opposite an incorporating direction. The stoppers 110 and 111 are fixed to the upper surface of a casing 101 or a cover 108, and the spindle motor rotating part regulates a movement in a direction opposite the spindle fixing side incorporating direction caused by external shocks. Thus, the spindle motor rotating part and the spindle motor fixing part can use a spindle motor using the oil-containing bearing not fixed in a rotational axis direction. Therefore, the number of part items is reduced compared with the ball bearing spindle motor, and parts costs and the number of assembling steps are reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a magnetic disk drive, and more particularly to a magnetic disk drive using a relatively small diameter magnetic disk.

[0002]

2. Description of the Related Art Magnetic disk drives have come to be mounted not only on large computers and workstations but also on personal computers. With the rapid spread of low-priced personal computers, the price of magnetic disk drives has also been remarkably reduced. Accordingly, cost reduction of magnetic disk devices has been strongly demanded, and cost reduction of spindle motors having high component costs in magnetic disk devices has been sought.

At present, a spindle motor using a ball bearing and a dynamic pressure bearing is used as a spindle motor of a magnetic disk drive. In particular, the magnetic disk device has become a device in which the positioning accuracy of the magnetic head is strongly required in order to cope with cost reduction by improving the surface density. Therefore, a spindle motor using a ball bearing having good processing accuracy and rotation accuracy is most used for a magnetic disk drive.

FIG. 6 is a sectional view of an inner ring rotating ball bearing spindle motor. The ball bearing 603 is disposed vertically above and below the shaft 606 so that the shaft 606 has a degree of freedom in the rotation axis direction and supports the shaft 606, and a magnetic circuit including a stator coil 600 and a magnet 601 for generating a rotational driving force on the outer peripheral side of the ball bearing 603. It has a structure in which the portion 602 is arranged.

In the spindle motor, a ball bearing 6 is used.
Reference numeral 03 applies a preload B in the direction of the rotation axis, and is fixed to the base. That is, the spindle motor includes a spindle motor rotating unit including the disk 100, the shaft 606, the hub 605, and the magnet 601, and a spindle motor fixing unit in which the stator unit including the stator coil 600 is fixed to the housing 101. You. Then, the spindle motor rotating unit is shifted in the upward direction in FIG. 1 by applying the preload B, but the upward shift is restricted by the interposition of the ball bearing 603, and the spindle motor rotating unit is positioned.

The magnetic disk 100 is fixed to the hub 605 by the clamp 102, and the magnetic disk 100 does not move in the direction of the rotation axis. The spindle motor using the above-described ball bearing 603 has been used in a magnetic disk drive to improve the processing accuracy of the ball bearing, and by changing the arrangement of the bearings, the rotational accuracy has been increased, thereby coping with higher recording density.

However, when the above-mentioned measures are taken, the number of parts increases and the assembly line becomes complicated, which is disadvantageous for further cost reduction. Actually, the cost ratio of the spindle motor in the magnetic disk device is higher than other components used in the magnetic disk device. Therefore, in the low price competition for the magnetic disk devices described above, there has been a strong demand for lowering the cost of the spindle motor.

[0008]

Therefore, a low-cost spindle motor used in a magneto-optical disk drive or the like is an inexpensive spindle motor using an oil-impregnated bearing without using a ball bearing. It can be said that the use of the oil-impregnated bearing spindle motor is an effective means for reducing the cost of the magnetic disk drive.

FIG. 7 is a sectional view of a spindle motor using an oil-impregnated bearing. The oil-impregnated bearing spindle motor includes a stator coil 600 that arranges the oil-impregnated bearing 700 so that the shaft 702 has a degree of freedom in the rotation axis direction and supports the shaft 702, and generates a rotational driving force on the outer peripheral side of the oil-impregnated bearing 700. It has a structure in which a magnetic circuit unit 602 including a magnet 601 is arranged. The structure of the oil-impregnated bearing spindle motor requires fewer parts than the ball bearing spindle motor as shown in FIG. 6, and can reduce the cost of parts and assembly, which is effective in reducing the cost of the magnetic disk drive.

However, in the oil-impregnated bearing spindle motor, the magnetic disk 100 is attached to the hub 703 by the clamp 10.
The rotating body fixed by 2 is not fixed to the spindle motor fixed portion side in the rotation axis direction. Therefore, when an external impact is applied to the magnetic disk drive, the suspension 705 is sandwiched between the magnetic disk 100 and the cover 108, and the slider 704 comes into contact with the magnetic disk 100, causing damage to the magnetic disk 100 and suspension of the suspension 70.
It is conceivable to give plastic deformation to No. 5. As a result, not only the error rate of the recording signal is deteriorated, but also a disk crash may occur. Therefore, the oil-impregnated bearing spindle motor is not suitable for the spindle motor of the magnetic disk drive.

In order to prevent the magnetic disk from being damaged by an external impact, there has been proposed a spindle motor in which a stopper is provided on the oil-impregnated bearing itself. However, the structure is complicated and the provision of the stopper shortens the bearing span ( (Because the thickness of the entire magnetic disk device is specified)
Since the space in the magnetic circuit section becomes thinner, the motor performance deteriorates.

An object of the present invention is not to use an oil-impregnated bearing having a special structure as described above, but to employ an oil-impregnated bearing having a normal structure in a magnetic disk drive to achieve a rotation accuracy and rotation equal to or higher than that of a ball bearing. To obtain performance and reduce costs (reduction of parts cost and assembly cost)

[0013]

In order to solve the above problems, the present invention mainly employs the following configuration.

At least one magnetic disk, a spindle motor for rotating the magnetic disk, a magnetic head for recording or reproducing information on the magnetic disk, and sealing the magnetic disk, the spindle motor and the magnetic head And a cover, comprising:
A magnetic disk drive provided with a stopper at a position facing the magnetic disk surface so that the spindle motor rotating unit does not shift by a predetermined amount or more in a direction opposite to a mounting direction of the spindle motor rotating unit into the spindle motor fixing unit.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A magnetic disk drive according to an embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows a first configuration example of a spindle motor rotating unit stopper mechanism in a magnetic disk device according to an embodiment of the present invention. FIG. 1A is a schematic plan view of a magnetic disk device without a cover. FIG. 1B is an enlarged sectional view taken along the line AA of FIG.

The magnetic disk drive according to the present embodiment includes a magnetic circuit unit 115 including one or more magnetic disks 100 and a spindle motor rotating unit having the magnetic disk 100 fixed to a magnetic disk receiving surface of a hub 114 by a clamp 102. A magnetic head 107 for recording or reproducing information on or from the magnetic disk 100, and a housing 10 for sealing the magnetic disk 100, the spindle motor and the magnetic head 107.
1 and a cover 108.
The magnetic head 107 is attached to the tip of the suspension 103, and is driven and controlled by the VCM 106. Signals read and written from the magnetic head 107 are read / write IC 10
5 and the like, the magnetic disk drive circuit board (omitted in FIG. 1)
Sent to

The magnetic disk drive shown in FIG.
The installation direction of the spindle motor rotating unit including the magnetic disk 100, the shaft 112, and the hub 114 (FIG. 1)
In order to limit the amount of movement of the rotating part of the spindle motor in the direction opposite to the direction (downward on the paper surface in the example of FIG.
0, 111 are arranged. Stoppers 110, 11
The L / UL (Load Unload) lamp 11 is fixed to the upper surface (cover contact surface) of the housing 101 from above with screws or equivalent means.
3 and one or more stoppers 111
The spindle motor rotating unit restricts movement of the spindle motor rotating unit in a direction opposite to the mounting direction due to an external impact.

Here, the stopper 110 is also used as an L / UN lamp for the magnetic head. According to FIG. 1B, the upper surface of the stopper 110 functions as a ramp, and the lower surface of the stopper 110 is a disk. It has a stopper function. And the stopper 111 is the stopper 11
It is installed on the side opposite to the center of the disk with respect to 0 to effectively function as a stopper against external impact. In the example of FIG. 1, the stopper 110 is also used as a ramp, but the stopper 110 is not limited to the dual purpose, and may be installed alone around the magnetic disk.

The oil-impregnated bearing shown in FIG. 1 (b) forms a bearing with the shaft 112, and the oil-impregnated bearing itself permits upward movement of the rotating portion of the spindle motor including the shaft. The spindle motor rotating portion is positioned vertically in response to an extremely slight impact due to magnetic coupling between the stator coil and the magnet.

FIG. 2 is an enlarged sectional view showing a fixed state of the stopper. In the magnetic disk device according to the present embodiment, the distance between the upper surface 100a of the magnetic disk and the stopper surface 110a facing this surface is d1, and the distance between the upper surface 103a on the cover side of the suspension guide arm 116 and the inner surface 108a of the cover. Is d2, and the distance between the lower surface of the suspension guide arm 116 and the upper surface of the magnetic disk is d3.
> D1, d2 is set so that d2> d1. Here, the reason for setting d1 <0.3 mm is that the distance between the magnetic disk and the lower surface of the suspension guide arm is approximately 0.3 mm.
This is because d1 <0.3 mm so that the magnetic disk contacts the stopper prior to the suspension.

With this setting, it is possible to prevent damage to the magnetic disk and deformation of the suspension due to the magnetic disk colliding with the suspension guide arm under the influence of an external impact. Further, it is possible to prevent the suspension from contacting the cover due to the rotation of the spindle motor rotating unit in the direction of the rotation axis.

Therefore, when an impact is applied to the magnetic disk drive, the rotating portion of the spindle motor is driven by the stoppers 110 and 1.
11 restricts the operation of the magnetic head 107 and the suspension 103 from being deformed in the direction opposite to the direction in which the magnetic head 107 and the suspension 103 are mounted on the spindle fixing portion, enables the oil-impregnated bearing spindle motor to be used in the magnetic disk device, and reduces the cost of the magnetic disk device. Can be provided.

Further, as described above, the stopper is L / U
By arranging one or more lamps other than the L lamp 113,
Since the magnetic disk is not inclined with respect to the rotation axis, the error rate is not deteriorated and the structure has a strong positioning accuracy.

Further, since there is no need to provide a stopper mechanism in the oil-impregnated bearing spindle motor itself, the cost of parts can be kept low, and a low-cost magnetic disk drive can be realized. Furthermore, by not providing a stopper on the bearing itself, the bearing span can be lengthened,
The amplitude of the rocking mode vibration of the magnetic disk 100 can be kept small, which is advantageous for positioning accuracy. Further, it is advantageous for reducing the thickness of the magnetic disk drive.

FIG. 5 is an enlarged perspective view and an enlarged front view showing the related structure of the magnetic head, the tip of the suspension, and the L / UL lamp. In FIG. 5, 100 is a magnetic disk, 103 is a suspension, 109 is a slider, 501 is a lift tab, 500 is an L / UL lamp,
Reference numeral 502 denotes a lift tab guide interval, which illustrates that the lift tab 501 at the tip of the suspension 103 can be regulated so as not to enter the guide interval 502.

FIG. 3 is a view showing a second configuration example of the spindle motor rotating portion stopper mechanism in the magnetic disk drive according to the embodiment of the present invention. FIG. 3A shows a cover provided with a stopper mechanism. FIG. 3 is a schematic sectional view and FIG.
FIG. 4B is a schematic sectional view in which members that generate less dust when the magnetic disk comes into contact with the cover are arranged.

The magnetic disk drive shown in FIG.
The opposite side to the magnetic disk 100 such that the spindle motor rotating unit including the magnetic disk 100, the shaft 303, and the hub 302 does not shift more than a predetermined amount in the direction opposite to the mounting direction on the spindle motor fixing unit side. , A cover 300 having a stopper function is arranged. The stopper mechanism shown in FIG. 3A is configured such that the cover 300 has a stepped shape facing the upper surface on the outer peripheral side of the magnetic disk 100. The cover 300 having the stopper mechanism is fixed to the upper surface of the housing 101 by screws or a means equivalent thereto to seal the magnetic disk device. In the cover 300, the stopper is arranged so as to surround the outer periphery of the magnetic disk 100.

The magnetic disk drive shown in FIG.
The rotating part of the spindle motor including the magnetic disk 100, the shaft 303 and the hub 302 is mounted on the magnetic disk 1 in the direction opposite to the mounting direction on the spindle motor fixing part side.
The stopper 301 is arranged on the inner wall of the cover 304 on the opposing surface of “00”. The member of the stopper 301 is a seal or a member that generates less dust due to contact with the magnetic disk 100 even if it comes into contact with the magnetic disk 100.
04 is fixed to the inner wall. By arranging the stopper 301, the height of the magnetic disk can be adjusted at the same time.

FIG. 4 is an enlarged view of the spindle motor rotating unit stopper mechanism shown in FIG. 3B. In the magnetic disk drive according to the embodiment of the present invention, the upper surface 100a of the magnetic disk and the stopper surface 301 facing the upper surface 100a.
the distance between the suspension guide arm 1 and the suspension guide arm 1
16 cover side upper surface 103a and cover inner surface 300a
Of the suspension guide arm 116
When the distance between the lower surface of the magnetic disk and the upper surface of the magnetic disk is d3,
Under the condition d1 <0.3 mm, d1 is set so that d3> d1 and d2> d1. Here, d1 <0.3 mm
The reason is that the distance between the magnetic disk and the lower surface of the suspension guide arm is about 0.3 mm, so that d1 <
This is because the thickness of the magnetic disk is set to 0.3 mm so that the magnetic disk contacts the stopper before the suspension.

With this setting, it is possible to prevent the magnetic disk from being damaged and the suspension from being deformed due to the magnetic disk colliding with the suspension guide arm due to an external impact. Further, it is possible to prevent the suspension from contacting the cover due to the rotation of the spindle motor rotating unit in the direction of the rotation axis.

Therefore, according to the above-described embodiment, the operation in the direction opposite to the mounting direction on the spindle fixing portion side is restricted, the deformation of the magnetic head 107 and the suspension 103 can be prevented, and the oil-impregnated bearing spindle motor can be used in the magnetic disk drive. Thus, a low-cost magnetic disk drive can be provided.

In the above description, the stopper is arranged to face the magnetic disk. However, the stopper is arranged on the side opposite to the direction in which the spindle motor rotating unit is mounted on the spindle motor fixed side. In the above description, the magnetic disk is not limited to being integrated as an integral structure fixed to the spindle motor rotating unit, but may be a magnetic disk fixed by a clamp after the spindle motor rotating unit is assembled to the fixed unit. In this case, the stopper is disposed on the side opposite to the direction in which the magnetic disk is mounted on the spindle motor fixed side.

In the above description, an oil-impregnated bearing has been described as an example of a bearing whose spindle motor rotating portion is not mechanically fixed in its mounting direction. However, such a non-fixed bearing is not limited to an oil-impregnated bearing. Also, a bearing using a plastic having good lubrication characteristics can be an application example of the present embodiment.

As described above, the embodiments of the present invention include those having the following configuration and functions or functions.

One or more magnetic disks, a spindle motor for rotating the magnetic disk, a magnetic head for recording or reproducing information on the magnetic disk, and the magnetic disk, spindle motor and magnetic head And a cover for sealing, the magnetic disk is clamped to the magnetic disk receiving surface of the spindle motor rotating unit after the spindle motor rotating unit is assembled in the direction of the rotating shaft on the spindle motor fixing unit side. In the magnetic disk fixed in the above, a stopper is provided in a housing or a cover on the magnetic disk facing surface on the opposite side of the mounting direction of the magnetic disk.

Further, the material of the stopper of the magnetic disk is made of a material softer than the magnetic disk 100. Further, the magnetic disk stopper is used on a disk upper surface outside a data area of the magnetic disk.

With the above-described features, the rotation of the spindle motor rotating unit in the direction opposite to the mounting of the magnetic disk beyond the restriction of the magnetic force by the magnetic circuit unit can be restricted. Also, the suspension
Since the magnetic disk contacts the stopper before contacting the magnetic disk, damage by the suspension can be prevented. Further, it is also possible to restrict the lift tab 501 at the tip of the suspension 103 from entering between the lift tab guides of the L / UL lamp 500.

[0038]

According to the present invention, it is possible to use a spindle motor in which the spindle motor rotating section and the spindle motor fixing section are not fixed in the direction of the rotation axis as the spindle motor of the magnetic disk drive. As a result, the number of parts is reduced as compared with the ball bearing spindle motor, and the cost of parts can be reduced.

Further, since the number of parts is reduced, the number of assembling steps can be reduced, so that the number of spindle motors can be reduced, and a low-cost magnetic disk drive can be provided.

[Brief description of the drawings]

FIG. 1 is a view showing a first configuration example of a spindle motor rotating unit stopper mechanism in a magnetic disk device according to an embodiment of the present invention, and FIG. 1A is a schematic plan view of a magnetic disk device with a cover removed; FIG. 1 (b) shows the A-
FIG.

FIG. 2 is an enlarged view of a spindle motor rotating unit stopper mechanism shown in FIG. 1;

FIG. 3 is a view showing a second configuration example of a spindle motor rotating unit stopper mechanism in the magnetic disk drive according to the embodiment of the present invention, and FIG. 3A is a schematic cross-sectional view in which a cover is provided with a stopper mechanism; FIG. 3B is a schematic cross-sectional view in which members that generate less dust when the magnetic disk comes into contact with the cover are arranged.

FIG. 4 is an enlarged view of a spindle motor rotating unit stopper mechanism shown in FIG. 3 (b).

FIG. 5 is an enlarged perspective view and an enlarged front view showing a related structure of a magnetic head, a suspension tip, and an L / UL lamp.

FIG. 6 is a schematic sectional view of a ball bearing spindle motor used in a conventional magnetic disk drive.

FIG. 7 is a schematic sectional view of an oil-impregnated bearing spindle motor used in a magneto-optical disk device.

[Explanation of symbols]

 REFERENCE SIGNS LIST 100 magnetic disk 101 housing 102 clamp 103,705 suspension 104,501 lift tab 105 R / W IC 106 VCM 107 magnetic head 108,300,301 cover 109,704 slider 110,111,301 stopper 112,303,606,702 shaft 113,500 L / UL lamp 114,302,605,703 Hub 115,602 Magnetic circuit unit 116 Suspension guide arm 502 Lift tab guide interval 600 Stator coil 601 Magnet 603 Ball bearing 604,701 Thrust plate 700 Oil bearing

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 5D059 LA01 5D076 AA01 BB01 CC05 DD02 DD08 DD20 EE03 FF04 GG20 5D109 BB01 BB12 BB17 BB21 BB23 5H605 BB05 BB10 BB14 CC04 DD09 EB03 EB06 EB13

Claims (8)

[Claims] At least one magnetic disk, a spindle motor for rotating the magnetic disk, a magnetic head for recording or reproducing information on the magnetic disk,
A cover for sealing the magnetic disk, the spindle motor, and the magnetic head, wherein the spindle motor rotating unit shifts by a predetermined amount or more in a direction opposite to a mounting direction of the spindle motor rotating unit to the spindle motor fixing unit. A magnetic disk device characterized in that a stopper is provided at a position facing the surface of the magnetic disk so as not to prevent it. 2. The magnetic disk drive according to claim 1, wherein a mounting direction of the spindle motor fixing unit to the spindle motor fixing unit or a mounting direction of the spindle motor rotating unit to which the magnetic disk is fixed is set. A magnetic disk drive characterized by a magnetic disk mounting direction. 3. The magnetic disk drive according to claim 1, wherein said spindle motor rotating portion has a structure supported by an oil-impregnated bearing. 4. The magnetic disk drive according to claim 1, wherein the stopper is also used as a ramp for a load / unload mechanism. 5. The magnetic disk drive according to claim 1, wherein the stopper is provided on a housing for fixing a spindle motor or on the hermetic cover. 6. The magnetic disk device according to claim 1, wherein the stopper has a structure in which a portion of the sealing cover facing an outer peripheral surface of the magnetic disk is recessed toward the magnetic disk. Magnetic disk drive. 7. The magnetic disk drive according to claim 1, wherein a distance between an upper surface of the magnetic disk and a stopper surface facing the upper surface is d1, and an upper surface of a suspension guide arm on a cover side and an inner surface of the cover are formed. When the interval is d2 and the interval between the lower surface of the suspension guide arm 116 and the upper surface of the magnetic disk is d3, the condition d1 <0.
At 3 mm, d1 is set so that d3> d1 and d2> d1.
A magnetic disk drive characterized by setting: 8. One or more magnetic disks, a spindle motor for rotating the magnetic disks, a magnetic head for recording or reproducing information on the magnetic disks,
In the magnetic disk device, the rotating part of the spindle motor to which the magnetic disk is fixed is supported by an oil-impregnated bearing, and the magnetic disk that moves in the bearing direction by an external impact collides with a suspension having the magnetic head attached to the tip. A magnetic disk drive characterized in that it comes into contact with a stopper before.