JP2003168271A - Apparatus for writing servo information of magnetic disk - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a servo track writer which can efficiently write servo information in a magnetic disk of a single plate disk HDD, suppress the height of a spindle and reduce an amount of asynchronous deflection even when many disks are stacked, and improve the manufacturing efficiency of the HDD of the single plate disk. <P>SOLUTION: The outside diameter of the spindle of the servo track writer is smaller than the inside diameter of the magnetic disk. The servo track writer includes a hollow cylinder part into which the magnetic disk is inserted along the side face of the outside diameter, and a plurality of spacer rings with predetermined thickness which loosely fit to the side face of the outside diameter of the cylinder part and have an outside diameter somewhat larger than the inside diameter of the magnetic disk. The magnetic disks are inserted and stacked on the cylinder part through the spacer rings. Air blow holes which correspond to the position of each stacked magnetic disk and spacer ring and communicate with the hollow part of the cylinder part is substantially provided radially relative to the center of the cylinder part, and pressurized air is introduced into the hollow part. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for writing servo information on a magnetic disk (hereinafter referred to as a servo track writer), and more specifically, it efficiently sets servo tracks on a magnetic disk of a single-disk magnetic disk drive. The present invention relates to a servo track writer capable of suppressing the height of the spindle even if a large number of magnetic disks are stacked, reducing the amount of asynchronous runout, and improving the manufacturing efficiency of a single-disk HDD.

[0002]

2. Description of the Related Art A hard magnetic disk drive (hereinafter simply referred to as HD) used for data storage in a computer system.
Servo information for controlling the position of the magnetic head and the like is set by a servo track writer on the magnetic disk (hereinafter simply referred to as "disk") mounted in D). Normal,
As for the disc, one disc or a plurality of discs are laminated to form a disc package, and servo information is set for these disc packages. As the setting method, there are a servo surface method in which one surface of one disk among a plurality of disks is dedicated to servo information, and a data surface method (or sector servo method) in which each track of each disk is set. In recent small disks, the number of disks is often one or two, and the data surface method is used. In this data surface method, the same servo information is set in each sector of each track on both the front and back sides of one disk. An example of this type of technology is Japanese Patent Application Laid-Open No. 10-106194, "Method for setting servo track of disk drive".

Since high precision is required for writing servo information, the runout of the spindle becomes a problem. As a servo track writer for which this kind of technology has been a problem, Japanese Patent Application Laid-Open No. HEI 7-96
-230678 "Servo data writing device and servo data writing method of magnetic disk device". As described in the prior art in this specification (publication), when a servo track is set for an HDD by a servo track writer, a method in which the fixed shaft of the disk rotation mechanism of the HDD is cantilevered is used. There are three methods: a method of using a dummy cover to support the fixed shaft of the rotating mechanism in a two-sided supported state, and a method of using a top cover having an opening into which the positioning pins of the clock head and the magnetic head are inserted. In the first method, asynchronous shake is likely to occur in the rotating mechanism (its spindle), but in the latter two cases, since both ends of the rotating mechanism are supported, there is an advantage that asynchronous shake can be suppressed. However, the work efficiency of setting the servo track is worse than that of the former. As a means for solving such a point, Japanese Patent Laid-Open No. 7-230678 discloses that
An elevating mechanism that fixes the upper end of the rotating mechanism is provided to efficiently support both ends, improving the work efficiency of setting the servo track.

By the way, in recent years, as a magnetic head of a hard disk device, an MR head and a GM are used as its read side head.
A composite magnetic head incorporating an R head, a TMR head, etc. is used. The recording density is steadily improving to several giga / inch. Moreover, the number of tracks is increasing and the width is becoming narrower. In addition, the size of the disk is 3.3 inches or less, and a glass disk is also used as a substrate, and the number of single-plate HDDs equipped with one disk is increasing.

[0005]

As the density of the disk is increased and the number of tracks is increased, the work efficiency of setting servo tracks on one disk is deteriorated,
In addition, higher positioning accuracy is required. On the other hand, HDDs have begun to be installed in home appliances and AV equipment, and there is a strong demand for lower prices. Therefore, it is required to set servo tracks on the disk more efficiently. In the technique disclosed in Japanese Patent Laid-Open No. 7-230678,
We can no longer fully meet these demands. In order to meet such a demand, the applicant has filed Japanese Patent Application No. 2001-323.
No. 196 “Magnetic disk servo information writing device” is filed. This is because each disk can be separated and attached / detached, and an air bearing is installed on the upper part of the disk structure to set servo tracks on many disks at the same time. Are separated and can be incorporated in a single-plate HDD.

[0006] In this case, the spindle structure in which each disc can be attached and detached is such that disc chuck rings provided with forward and backward claws are stacked and the stacked discs are chucked by the claws. It is difficult to make the disc stacking interval narrower and the spindle height becomes higher. As the height of the spindle becomes higher, asynchronous runout is likely to occur accordingly. However, in the embodiment of the invention described above, since the air bearing is provided on the upper part of the spindle, such a problem is avoided. On the other hand, the higher the recording density of the disk, the higher the accuracy of the center positioning of the servo track is required. However, in the embodiment of the invention described above, the accuracy of the center positioning is somewhat different because of the stacking of the disc chuck rings. There was a drawback. An object of the present invention is to eliminate the above-mentioned drawbacks of the prior art and the conventional art, and it is possible to efficiently write servo information to a magnetic disk of a single-disk HDD, and The spindle height is suppressed even if many layers are stacked,
An object of the present invention is to provide a servo track writer that can reduce the amount of asynchronous shake and improve the manufacturing efficiency of a single-disk HDD.

[0007]

The features of the servo track writer of the present invention for achieving the above object are that a plurality of magnetic disks are detachably held substantially in parallel and the magnetic disks are rotated. In a servo information writing device for a magnetic disk, which has a spindle and rotates the spindle to write servo information to a plurality of magnetic disks simultaneously by a magnetic head, the spindle has an outer diameter smaller than an inner diameter of the magnetic disk. A hollow cylinder portion along which the magnetic disk is inserted along the outer diameter side surface, and a plurality of predetermined thicknesses that are loosely fitted to the outer diameter side surface of the cylinder portion and whose outer diameter is slightly larger than the inner diameter of the magnetic disk. A magnetic disk is inserted into the cylinder portion via the spacer ring and laminated, and each of the laminated magnetic disks and the spacers has a spacer ring. Substantially radially arranged air outlets corresponding to the position of the Saringu communicates with the hollow portion of the cylinder portion with respect to the center of the cylinder portion, the hollow portion in which the pressure air is introduced.

[0008]

As described above, according to the present invention, the outer diameter of the spindle itself is made smaller than the inner diameter of the disk so that the disk can be attached to and detached from the spindle, and the cylinder is free from play. By alternately arranging a plurality of spacer rings with a predetermined thickness, the fitting outer diameter of which is slightly larger than the inner diameter of the disc, the discs can be stacked at narrow intervals, and many discs can be chucked in this stacked state. it can. Also, the air blowout holes are provided so as to be substantially radial with respect to the center of the cylinder portion, so that when the pressurized air is introduced into the hollow portion when the discs are not chucked in the stacked state, the spacer ring is formed. Since the disk is in the loose fitting state, the disk moves in a direction in which it does not become eccentric, which allows the disk to be centered. At this time, since the spacer ring is also centered at the same time, the eccentricity is corrected for each and sufficient disk chucking can be performed. As a result, single disk HDD
Servo information can be efficiently written on the magnetic disk of, and the height of the spindle can be suppressed even if a large number of disks are stacked, so that asynchronous runout is less likely to occur, and a single-disk HDD Manufacturing efficiency can be improved.

[0009]

1 is a sectional explanatory view of an embodiment of a servo track writer according to the present invention, and FIG. 2 is a partial sectional explanatory view of a mechanism of a spindle block to which eight disks are attached and detached, and FIG. FIG. 6 is a cross-sectional explanatory diagram of a spindle block in a disc chuck state. Is. In FIG. 1, 1
Is a servo track writer and includes eight discs 2a
The spindle block 3 to which 2 h to 2 h are detachably attached is detachably attached to the air spindle 4. Reference numeral 5 denotes an air supply mechanism for supplying air into the spindle block 3, which is fixed to the frame 9a and communicates with the center hole 36 (see FIG. 2A) of the spindle block 3 via the communication passage 6. . Spindle block 3
As shown in the sectional view of FIG. 2A, the spindle body 30 and spacer rings 30a to 30h as spacers
Consists of. The spindle body 30 includes a base cylinder portion 31, a step portion 32, and a disk insertion cylinder portion 3
3 and the lock head 34. The base cylinder portion 31 has an outer diameter slightly larger than the inner diameters of the disks 2a to 2h, has an outer diameter corresponding to the outer diameters of the spacer rings 30a to 30h, and passes through the step portion 32 to have the outer diameters of the disks 2a to 2h. Is continuous with the disc insertion cylinder portion 33 having a diameter smaller than the inner diameter.

Spacer rings 30a to 30h are inserted as spacers on the outside of the disk insertion cylinder portion 33, and the inner diameters of the spacer rings 30a to 30h are the same as the disk insertion cylinder portion 33 of the spindle body 30.
Has a diameter loosely fitted to the outer diameter of the. Its outer diameter is slightly larger than the inner diameter of the disc, and its thickness is such that the magnetic head can be inserted and the disc can be handled. Disks 2a-2h and eight spacer rings 30a-30
h and h are alternately fitted and inserted into the disk insertion cylinder portion 33, and these are laminated as shown in the drawing. Then, these are pressed and fixed by the lock head 34. As a result, each disk is chucked by the spacer ring. The lock head 34 is lowered by the urging force of a spring 37 (see FIG. 2A) mounted on the rear disk 34c in a compressed state, and receives the force of the spring 37 and presses the uppermost spacer ring 30a. As shown in FIG. 2 (a), the lock head 34 includes a head disc 34a, a through screw 34b screwed with the head disc 34a, and a rear disc 34c that is coupled to the other end of the through screw 34b at its center. Consists of. A spring 37 is mounted on the rear disc 34c in a compressed state between its peripheral portion 34d and the flange 31a of the base cylinder portion 31. Further, the through screw 34b is attached to the rear disk 34.
The rear disk 34c, which is connected to c, has its freedom in the rotational direction constrained (this constraint is due to the key groove), and has the freedom in the cylinder axial direction. And the head disk 34a
The through screw 34b and the through screw 34b can be attached and detached by turning the head disc 34a.

In the disk insertion cylinder portion 33, the inserted disks 2a to 2h and spacer rings 30a to 30 are included.
16 stages of air blow-out holes 35, 35, ... Are opened in the cylinder axial direction at predetermined intervals in the stacking direction corresponding to the position of h (see a partially enlarged view of FIG. 2B). Further, as shown in FIG. 3, the air blowout holes 35, 35, ... Have a central hole 36 in a direction parallel to the inserted disk.
It is opened in a radial pattern in the horizontal direction. The air blowing holes 35, 35 substantially correspond to the centers of the disc insertion cylinder portion 33 at the respective positions corresponding to the laminated positions of the discs 2a to 2h and the spacer rings 30a to 30h. In the radial direction (or rotational symmetry), three or more are provided at least at equal angles. Note that FIG. 3 is a cross-sectional view of the disc insertion cylinder portion 33 cut along the horizontal plane above the disc 2a. Then, as shown in FIG. 2A, the rear disc 34
c is pushed up by the forward movement of the piston rod 38a by the push-up actuator 38, and air is supplied from the lower side to the central hole 36 by the air supply mechanism 5, so that air is radially emitted from the air blowing holes 35, 35, .... The side surfaces of the disks 2a to 2h and the spacer rings 30a to 30h, which are blown out and inserted into the disk insertion cylinder portion 33, are pressed against their side surfaces to perform center positioning of these. The drive by the push-up actuator 38 is released, and the rearward movement of the piston rod 38a releases the push-up of the rear disk 34c. As a result, the rear disk 34c is lowered by the spring 37 and the disks 2a to 2h and the spacer rings 30a to 30h are positioned so that the disks 2a to 2h are centered. By descending of 34a, it is fixed to the spindle body 30 via spacer rings 30a to 30h. In this state, the air spindle 4 is driven and servo information is written on each of the disks 2a to 2h. Of course, the push-up actuator 38 can be provided on the bottom of the air spindle 4. Further, it is driven by the drive control circuit 10 shown in FIG.

In FIG. 1, the magnetic head and its supporting arm,
Although the head carriage mechanism is not shown, the servo tracks are set here by the self-driving method as described in JP-A-10-106194, "Method for setting servo tracks of disk drive". It is something to write. In this, a mirror is fixed to the uppermost support arm of the support arms that support the magnetic head, and the length measurement system receives the reflected light of this mirror to set the head access position. The setting work is performed in a clean room, the drive control circuit 10 drives the air spindle 4, the disks 2a to 2h rotate, and a control circuit (not shown) supplies a drive current to the VCM (voice coil motor) to move the support arm. The heads are rotated to sequentially move the heads, and the heads are positioned at the correct writing positions while the positions are measured by the length measuring system, and the servo signals are sequentially written to the predetermined positions (predetermined tracks). In this way, after setting the servo track on each disk, the spindle block 3 is removed from the air spindle 4 by the robot hand (not shown), and the head disk 34a of the spindle block 3 is removed from the through screw 34b. , Disks 2a-2h and spacer rings 30a-30
If h and h are alternately removed from the disc insertion cylinder portion 33 by the robot hand, the discs can be separated one by one. Then, the new disk is reversed, and the disks 2a to 2h and the spacer rings 30a to 30h are alternately inserted into the spindle block 3 by the robot hand, and the disk is mounted on the spindle block 3.

By the way, here, the air spindle 4
Is fixed to the central portion of the base 9, and a chuck for holding the base cylinder portion 31 is provided on the head of the air spindle 4 so that the spindle block 3 can be attached and detached. It has a structure that fits as much as possible. However, the spindle block 3 and the air spindle 4 may be integrated with each other and may not necessarily have a detachable structure.

As described above, in the embodiment, the head disk 34a and the penetrating screw 34b are screwed together, and the head disk 34a is removed from the penetrating screw 34b so that the disk can be attached and detached. This connection form is not limited to screwing. For example, the diameter of the head disk 34a is made smaller than the inner diameter of the disk, and the spacer ring 30h
Protrusions are provided at equal intervals on the outer periphery of the head disk 34a, and rectangular notch grooves larger than the protrusions are provided on the outer periphery of the head disk 34a at equal intervals. The disk may be fixed by rotating the head disk 34a to engage the protrusion of the spacer ring 30h with the outer circumference of the head disk 34a and pressing it with the biasing force of the spring 37. If the rectangular cutout groove of the head disk 34a is rotated to the position of the protrusion, the outer circumference of the head disk 34a will no longer engage with the protrusion, the spacer ring 30a will come off, and other spacer rings can also be removed. Can be easily removed from the cylinder. In the embodiment, the disk is rotationally driven by the air spindle 4, but it goes without saying that this may be a spindle of a normal bearing.

[0015]

As described above, according to the present invention, a plurality of spacer rings having a predetermined thickness, which are loosely fitted in the cylinder portion and whose outer diameter is slightly larger than the inner diameter of the disc, are alternately arranged with the disc. As a result, the disks can be stacked at narrow intervals, and a large number of disks can be chucked in this stacked state. Further, since the air blowout holes are provided so as to be substantially radial with respect to the center of the cylinder portion, the center position of the disk can be positioned by introducing pressurized air into the hollow portion. At this time, the spacer ring is also centered at the same time, so the eccentricity is corrected for each.
Sufficient disc chuck can be done. As a result, the servo information can be efficiently written to the magnetic disk of the single disk HDD, and the spindle height can be suppressed even if a large number of disks are stacked, so that asynchronous runout is less likely to occur. It is possible to improve the manufacturing efficiency of a single plate HDD.

[Brief description of drawings]

FIG. 1 is a sectional explanatory view of an embodiment of a servo track writer of the present invention.

FIG. 2 is a partial cross-sectional explanatory view of a mechanism of a spindle block to which the eight disks are attached / detached, (a)
Is a vertical sectional view thereof, and (b) is a partially enlarged view thereof.

FIG. 3 is a cross-sectional explanatory diagram of a spindle block in a disc chuck state.

[Explanation of symbols]

1 ... Servo track writer, 2a-2h ... Disk, 3
0a to 30h ... Spacer ring, 3 ... Spindle block, 4 ... Air spindle, 5 ... Air supply mechanism, 6 ...
Communication passage, 36 ... central hole, 30 ... spindle body, 31 ...
Base cylinder portion, 32 ... Step portion, 33 ... Disk insertion cylinder portion, 34 ... Lock head, 34a ... Head disc, 34b ... Penetrating screw, 34c ... Rear disc, 34d ... Peripheral portion, 35 ... Air blowout hole, 37 ... Spring.

   ─────────────────────────────────────────────────── ─── Continued front page    F-term (reference) 5D096 WW02                 5D138 SA17 SA19 UA03 UA11 UA25                       UA28 UA30

Claims (3)

[Claims] 1. A spindle for rotating a magnetic disk by detachably holding a plurality of magnetic disks substantially parallel to each other, and by rotating the spindle, servo information is simultaneously applied to the plurality of magnetic disks by a magnetic head. In a servo information writing device for writing a magnetic disk, the spindle has an outer diameter smaller than the inner diameter of the magnetic disk, and a hollow cylinder portion into which the magnetic disk is inserted along the outer diameter side surface, The cylinder portion has a plurality of spacer rings that are loosely fitted to the outer diameter side surface and the outer diameter of which is slightly larger than the inner diameter of the magnetic disk. Are stacked via the magnetic disk and the spacer ring corresponding to the positions of the magnetic disk and the spacer ring, which are respectively stacked. A servo information writing device for a magnetic disk, wherein air blowout holes communicating with the hollow portion are provided substantially radially with respect to the center of the cylinder portion, and pressurized air is introduced into the hollow portion. . 2. Further, the plurality of magnetic disks are fixed to the cylinder portion via the plurality of spacer rings,
2. The magnetic disk servo information writing device according to claim 1, further comprising a fixing releasing mechanism for releasing the fixing, wherein the spindle is an air spindle. 3. The magnetic disk according to claim 2, wherein the fixing mechanism fixes the magnetic disk to the cylinder portion by pressing the uppermost spacer ring of the stacked spacer rings. Servo information writing device.