JP2001118346A - Disk drive device, controller for disk drive, method for controlling disk drive device and recording and reproducing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a disk drive device capable of suppressing the generation of noise in the case of recording and reproducing AV data and its controlling method. SOLUTION: This device sets an actuator control condition corresponding to the seek distance of a magnetic head, decides a distance when the magnetic head actually seeks and controls the actuator with the control condition corresponding the distance by controlling the seek of the magnetic head in the case of reading information recorded on a magnetic disk or writing information on the magnetic disk. For instance, the control shown in the diagram S1 is executed in the case of short stroke seek, the control shown in the diagram S2 is executed in the case of middle stroke seek, and the control shown in the diagram S3 is carried out in the case of long stroke seek.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a disk drive device used for a hard disk drive (HDD) and a control method therefor, and more particularly, to a magnetic disk for writing information on a recording medium or reading information therefrom. The present invention relates to control of an actuator that performs a seek on a recording medium of a head.

[0002]

2. Description of the Related Art In a conventional contact start / stop (CSS) type HDD, there is a possibility that a head slider is attracted to the surface of a data area or moved to a data area by an impact to damage a disk surface. Therefore,
For the purpose of avoiding such a problem and improving the reliability during non-operation, an HD called a load / unload type is used.
D is being developed. Load / unload type HDD
When reading information stored in the magnetic disk or writing information to the magnetic disk, the magnetic head is inserted into the magnetic disk from the retracted position, that is, loaded on the magnetic disk, and when the operation of the HDD is stopped, the magnetic head is The head is retracted from the magnetic disk onto the ramp, that is, unloaded. Currently, a voice coil motor (VCM) is used as an actuator for realizing this load / unload. The VCM not only loads and unloads the magnetic head, but also functions as an actuator for moving the magnetic head to a target track on the magnetic disk (this movement is called seek).
VCM is a contact start / stop (CS
It is also widely used as an actuator for seeking a magnetic head in an S) type disk drive.

Conventionally, HDDs have mainly been used to record data such as computer program files. Recently, however, HDDs have been used to store video data including audio such as TV programs, that is, audio-visual (AV) data. It is beginning to be used as a recording device. Conventionally,
A typical recording medium for recording video data is a magnetic tape, and a video tape recorder (hereinafter, VTR) for recording data on the magnetic tape is widely used.
However, since magnetic tape is inferior in random access,
A considerable amount of time is required for cueing. In addition, there is a demand that a user wants to view a separately recorded program while recording a certain TV program. However, the conventional VTR has no function to meet such a demand.

[0004]

Therefore, it has been studied to use an HDD having excellent random access property for recording AV data including a TV program. For example, a digital video unit described in Japanese Patent Application Laid-Open No. 11-504175 has a digital video tape and a disk drive, and records data once on a hard disk at the time of data recording, and then records the data on a digital video tape. The data is transferred and copied to a tape, and at the time of reproduction, the data recorded on the digital video tape is temporarily recorded on a hard disk and then transferred to a display. Tokiohei 1
According to the description of Japanese Patent Application Publication No. 1-504175, random access is enabled by using a hard disk, and it is possible to record another program while playing back a program stored on a digital video tape.

A problem when using an HDD for AV applications is how to reduce noise other than the original reproduced sound. That is, when noise occurs when writing or reading AV data to or from a magnetic disk, the noise is amplified and deteriorates the sound quality of the reproduced sound. The present inventors actually used an HDD used in a conventional personal computer to
When V data was recorded and reproduced, it was confirmed that there was room for further improvement in reproducing clearer audio.
Accordingly, it is an object of the present invention to provide a disk drive device capable of suppressing generation of noise when recording and reproducing AV data, and a control method thereof.

[0006]

SUMMARY OF THE INVENTION The present inventor has investigated the causes of noise when recording and reproducing AV data. As a result, they found that seek of the magnetic head was one of the causes of noise. Further, it has been found that the noise caused by the seek is more remarkable as the distance over which the magnetic head moves to a target track on the magnetic disk (hereinafter referred to as seek distance) becomes longer. On the other hand, when observing the actual usage environment of the conventional HDD, it was found that the frequency of seeks with a short seek distance was much higher than those with a long seek distance. Therefore, it has been found that in order to reduce the noise due to the seek, the noise in the seek having a long track length may be reduced. The present invention has been made based on the above findings, and a spindle motor that rotates at a predetermined rotation speed, a disk-shaped recording medium that is rotationally driven by the spindle motor, and reads or records information recorded on the disk-shaped recording medium. A disk drive device comprising: a head for writing; and an actuator for causing the head to seek on the disk-shaped recording medium and for driving the head under different control conditions depending on a seek distance.

The greatest feature of the disk drive of the present invention is that the actuator is driven under different control conditions depending on the seek distance of the head. In other words, as described above, when the seek distance is long, the noise caused by the seek becomes remarkable, but in an actual disk drive device, attention is paid to the fact that the frequency of the seek with the long seek distance is small, and when the seek distance is long, It is intended to drive and control the actuator under conditions that can reduce noise. Elements of noise due to seek are speed and acceleration when the actuator is driven (current value supplied to the actuator)
And the current slew rate. Therefore, the disk drive device of the present invention can drive the actuator with the maximum drive speed determined according to the seek distance. Further, the disk drive device of the present invention can drive the actuator by determining the current value according to the seek distance. Further, the disk drive device of the present invention can drive the actuator by determining the current slew rate according to the seek distance.

Here, the reason why the noise caused by the seek becomes prominent when the seek distance is long in the conventional disk drive device will be described. FIG. 7 shows V in a conventional HDD.
FIG. 3 is a diagram showing control of a CM, wherein the upper part shows the relationship between drive time (t) and drive speed (v) (time-speed diagram), and the lower part shows the relationship between drive time (t) and current (I). (Time-current diagram) is shown. As shown in FIG. 7, the conventional HDD drives the VCM under one control condition, that is, a single time-speed diagram (time-current diagram). When the seek distance is long, that is, if a long seek time and T ₁ is
As shown by the solid line in the figure, the VCM is accelerated and reaches the maximum speed, then decelerates and stops. However, if the seek distance is short, that is, if the seek time is short and T ₂ are, the driving speed of the VCM in the same acceleration and when the seek time as indicated by a broken line in FIG. Long and T ₁ (v) increases Decelerates before reaching the maximum speed V and stops. That is, the VCM is driven and controlled along the same time-speed diagram,
The speed reached by the CM was different. As can be easily understood, the noise due to the seek increases when the drive speed of the actuator is high. Therefore, in the conventional HDD, when the seek distance is long, the noise is remarkable.

In the conventional HDD, the VCM is driven under the same control condition regardless of the length of the seek distance, and the noise caused by the seek becomes prominent as the seek distance becomes longer. However, when pursuit of quick reading of a program file and writing of a data file is pursued, it is necessary to set a high seek speed, that is, to set a large VCM speed and acceleration. With the recent increase in recording density of magnetic disks, increasing the seek speed has been a trend in HDDs. The present invention deliberately deviates from this technical trend, and attempts to control the driving of the VCM so that noise does not become a problem when the seek distance is long. In other words, the seek distance of the magnetic head is detected, and the VCM is determined based on the detected seek distance.
Is characterized in that Therefore, according to the present invention, a VCM for seeking a magnetic head for reading or writing information from / on a magnetic disk, a seek distance detector for detecting a seek distance when the magnetic head seeks, and a seek distance And a controller for controlling the VCM based on seek distance information obtained by a detector.

In the disk drive of the present invention, the seek distance is defined by the number of cylinders of the magnetic disk on which the magnetic head moves, and the seek distance is defined by the number of cylinders (tracks) on which the magnetic head moves during seek. S ₁ , S ₂ , S ₃ ,... _SN (however, S ₁
It is classified into N blocks of <S ₂ <S ₃ <... <S _N ). Then, have configured the control condition of the VCM for each block, wherein the controller and the seek distance information _{S 1, S 2, S 3} , ... the V of the block by comparing the S _N
The VCM can be controlled according to the CM control conditions. As described above, the control conditions include the driving speed of the VCM and the current supplied for driving the VCM (hereinafter, VCM).
CM current) and the current slew rate can be set, and in addition, the acceleration until the actuator reaches its maximum driving speed can be set as the control target. In this case, the _{S 1, S 2, S 3} , ... the maximum acceleration of S _1a of the VCM in the _{S N, S 2a, S 3a} , ... When S _Na, S _1a>
The control conditions of the VCM may be set so that S _2a > S _3a >>...> S _Na . When the arm is at a certain position on the magnetic disk, the tracks on the disk can be read by the number of magnetic heads. This group of tracks is regarded as a virtual cylinder, and is called a cylinder.

An example of a method for setting the control conditions of the VCM will be described.
000. If the number of blocks to be classified is 4, the case where the number of cylinders to be moved at the time of seeking is ₁ to 3000 is S ₁ , and the case where the number of cylinders to be moved is 3,001 to 6,000 is S ₂ , 6,001 to 9, 000 for S ₃ , 9,001
In the case of 12,000 and S _4. And the S ₁ ,
The maximum acceleration of the VCM in S ₂ , S ₃ , and S ₄ is S _1a , S
_2a , S _3a , and S _4a are set. For example, if the number of cylinders to be moved at the time of seeking is 4,000, the VCM is driven at the acceleration S _2a , and if the number of cylinders is 8,500, the VCM is similarly set.
_Is driven by the acceleration _S3a . Here, the number of cylinders is set to 1,200 and the number of blocks is set to 4, but this is merely an example and is not a requirement to limit the present invention. In addition, the acceleration of the VCM (V
(Corresponding to the CM current), but the maximum drive speed of the VCM can be used, or the slew rate of the VCM current can be used.

As a control method suitable for the disk drive of the present invention described above, the present invention provides a disk drive for controlling the seek of a magnetic head when reading information recorded on a magnetic disk or writing information to a magnetic disk. In a control method, a control condition of an actuator according to a seek distance of the magnetic head is set, a distance when the magnetic head actually seeks is determined, and the control condition corresponding to the distance is used as the control condition. A control method of a disk drive device for controlling an actuator is provided by the present invention. In this method of controlling a disk drive device, the control condition of the actuator can be set in at least two stages according to a seek distance, and when the seek distance is long, the maximum seek speed by the actuator can be set smaller than when the seek distance is short. . This is to suppress generation of noise when the seek distance is long, as is apparent from the above description. Here, the extent to which the noise caused by seeking is suppressed is not uniquely determined, but can be determined according to individual applications. Then, a method is adopted in which a limit value of the noise due to seek is set for each individual application, a seek distance at which the noise due to seek is equal to or less than the limit value is determined, and the control condition of the actuator is set based on the seek distance. be able to. Further, it is effective to set the control condition of the actuator so that the current value supplied to the actuator is maximized at the seek distance where the noise due to the seek is equal to or less than the limit value.

This control will be described in a concrete form to some extent.
As described above, the noise due to the seek increases as the maximum drive speed of the VCM increases, and the seek distance may be limited in order to restrict the noise to the limit value or less, as described with reference to FIG. It is. Therefore, when a seek is performed using an actual disk drive device and the relationship between the noise caused by the seek and the seek distance is measured, the maximum seek distance K for achieving the limit value can be experimentally obtained. . When Replacing the maximum seek distance of the number of cylinders described above, it may be the S ₁ and settings from the cylinder number 1 to K. The number of cylinders exceeding K may be appropriately set in view of the performance of the disk drive device and required reading and writing speeds.

When the present invention is applied to, for example, an AV data recording / reproducing apparatus, a disk-shaped recording medium capable of random access, a head for reading or writing information from or to the recording medium, An actuator for the head to seek above,
The actuator includes a voice coil motor, and the head controls the maximum drive speed of the voice coil motor to be lower than the frequency of the short seek distance so that the frequency of the long seek distance is lower than the frequency of the short seek distance. This provides a recording and reproducing apparatus that reduces noise when the head randomly seeks on the recording medium.

In order to reduce the noise caused by seeking, it is conceivable to take measures such as using a special material or attaching a special cover to the housing and cover constituting the disk drive. However, these measures require a considerable cost, which is directly reflected in the cost of the disk drive. On the other hand, according to the present invention, it is possible to provide a low-noise disk drive device at low cost by using firmware of an existing disk drive device without adding new parts or using special materials. Has an effect. However, this does not exclude that the disk drive device to which the present invention is applied uses a special material or attaches a special cover to the housing and the cover.
In order to further reduce noise and obtain a quiet disk drive device, it is effective to use a special material or attach a special cover to the housing and cover in addition to the present invention.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to a hard disk drive (HDD) will be described below in detail with reference to the drawings. As shown in FIG. 1, in an HDD 10 as a disk drive device, an open upper portion of a base 12 made of a shallow box-shaped aluminum alloy is covered with a cover 14.
To form an enclosure case 16. The cover 14 made of brass is screwed to the base 12 via a rectangular frame-shaped sealing member (not shown), and the inside of the enclosure case 16 is airtight. An acoustic plate 42 is arranged on the upper surface of the cover 14. Acoustic plate 42 is enclosure case 1
6 is a member for preventing the noise inside 6 from leaking to the outside, and makes the quietness according to the present invention more effective. In the enclosure case 16, a spindle motor 18 composed of a three-phase DC servomotor having a hub-in structure is provided slightly near the center of the base 12. A magnetic disk 22 made of a glass substrate or an aluminum substrate is coaxially stacked on a top surface of a hub 20 of the spindle motor 18 with three spacers 26 interposed therebetween.
8 and is driven to rotate by a spindle motor 18.

An actuator 30 is provided in the enclosure case 16. The actuator 30 has a magnetic head 32 at one end, and an intermediate portion is supported on the base 12 via a pivot 34, and is rotatable around the pivot 34. A VCM coil 36 is integrated with the other end of the actuator 30, and the VCM coil 36 and the VCM stator 44 constitute a VCM. The actuator 30 is rotated by supplying a VCM current to the VCM coil 36. This rotation causes the magnetic head 32 to execute load / unload and seek. A card (not shown) as a circuit board is attached to the outer surface (lower surface) of the base 12, and the card is formed in a rectangle having a size to cover the outer surface of the base 12. Input / output of electric power, signals, and the like for driving the motor is performed between the card and the spindle motor 18.
Input and output of power and signals for power to the M coil 36, reading of the magnetic head 32, and the like are performed. Input and output between the card and the actuator 30 are performed via a flexible cable (FPC) 38. The HDD 10 according to the present embodiment is an HDD called a load / unload type.
It is 10. When the load / unload type HDD 10 is not operated, the magnetic head 32 of the actuator 30 is held by the ramp block 40 so as to unload the magnetic head 32 to the retracted position without making contact with the surface of the magnetic disk 22. is there. During operation, the magnetic head 32 is positioned on the magnetic disk 22 by driving the actuator 30.

Next, the HDD 10 according to the embodiment of the present invention
Will be described with reference to the block diagram of FIG. In FIG. 2, reference numeral 22 denotes a magnetic disk serving as a data recording medium (only one disk is shown), 30 denotes an actuator, 46 denotes a voice coil motor spindle driver (VCM spindle driver) including a spindle motor 18 for driving the magnetic disk 22 to rotate, 48 MP controls load / unload control, speed control of the actuator 30, and data read / write operation on the magnetic disk 22.
U / Hard Disk Controller
er: HDC). The magnetic disk 22 is located on the HDD 10
When the HDD 10 is operating, it is driven to rotate about the spindle axis of the spindle motor 18, and when the HDD 10 is not operating, the rotation is stopped (stationary). On the surface of the magnetic disk 22, tracks including a data area where data is recorded and a servo area where servo data is recorded in advance are arranged concentrically. The position of the magnetic head 32 can be known by reading the servo data by the magnetic head 32.

The VCM spindle driver 46 includes a spindle motor 18 for rotatingly driving the magnetic disk 22, a back electromotive voltage detection circuit for detecting a back electromotive voltage from the spindle motor 18 and the VCM coil 36, and a VCM coil 36.
And a switch for switching the VCM current and the current slew rate to be supplied to the VCM. The current and current slew rate switch switches the current or the current slew rate supplied to the VCM coil 36 in response to a command from the MPU / HDC 48. When the magnetic head 32 is above the surface of the magnetic disk 22, a servo signal 54 indicating the head position is input to the MPU / HDC 48.

The MPU / HDC 48 is provided on the magnetic disk 22.
And an MPU that controls the speed of the actuator 30 and controls load / unload prior to the speed control. The MPU 50 has a function of detecting a seek distance of the magnetic head 32, as described later. The memory 52 stores microcode as firmware. Based on the microcode, the MPU 50 controls the VCM spindle driver 46
When the magnetic head 32 seeks, the VCM coil 36
Current and the current slew rate can be commanded. The MPU / HDC 48 rotates the actuator 30 when the HDD 10 starts operating,
The head slider is loaded above the surface of the magnetic disk 22 that has started the rotation operation, and when the HDD 10 stops operating, a drive current is passed through the VCM coil 36 of the actuator 30 to rotate the actuator 30 to rotate the magnetic head 32. Is unloaded from above the surface of the magnetic disk 22 to the retracted position.

Next, the magnetic head 3 according to this embodiment will be described.
The second seek control will be described. First, it is assumed that the total number of cylinders of the magnetic disk 22 of the present embodiment is 9,000. A seek distance of 1 to 3000 cylinders is used for a short stroke seek, and a seek distance of 3.0
A seek of 01 to 6,000 cylinders is a middle stroke seek, a seek distance of 6,001 to 9,000 cylinders is a long stroke seek, and a seek distance is 3
Into three blocks. Short stroke seek,
FIG. 3 shows an example of VCM control conditions for the middle stroke seek and the long stroke seek. The upper diagram in FIG. 3 shows the driving time (t) and the driving speed (v).
(Time-speed diagram), and the lower part shows the relationship between drive time (t) and VCM current (I) (time-current diagram).
Is shown. That, is the largest VCM current when a short-stroke seek as shown in the diagram S ₁ in FIG. 3, accordingly the acceleration of the actuator 30 is the largest. Further, since the current supply time is long, the driving speed reached by the actuator 30 is the highest. Hereinafter, a middle stroke seek indicated diagrammatically S _2, acceleration and driving the maximum speed of the actuator 30 in order of the long stroke seek indicated diagrammatically S ₃ becomes smaller. FIG. 3 shows S ₁ , S ₂ ,
Note that the relative relationship of S ₃ is qualitatively shown and is not quantitatively accurate.

When a seek command is issued from the host, M
The PU 50 detects a seek distance, that is, the number of cylinders to be moved, from the position of the magnetic head 32 to be moved and the current position of the magnetic head 32 given from the servo signal 54. Then, the MPU 50 determines whether the number of cylinders to be moved corresponds to a short stroke seek, a middle stroke seek, or a long stroke seek, based on the microcode stored in the memory 52 based on the determination result. Spindle driver 46
V under any of the conditions S ₁ , S ₂ and S _{3 in} FIG.
Instructs whether to control CM. The VCM spindle driver 46 supplies a VCM current to the VCM coil 36 based on the command to execute a seek.

[0023] For short stroke seek, as shown in the diagram S ₁ in FIG. 3, the maximum driving speed of the actuator 30 is set to be larger. As described above, the noise caused by the seek becomes more remarkable as the maximum driving speed at the time of driving the actuator 30 increases. However, as shown by the thick line in FIG. Since the seek ends in a very short time, it has been confirmed that the noise level is not a problem. When the control under the conditions shown in long stroke short stroke seek similar diagrams S ₁ in the case of the seek respect more, longer time the actuator 30 accelerates, also long since the time to maintain the maximum drive speed, seek The noise caused by the noise becomes significant. Therefore, as shown in the diagram S ₃ in FIG. 3, the actuator 3
0 of acceleration, the maximum drive speed to shorten the supply time while reducing the VCM current supplied to the VCM coil 36 to be lower. Here, as apparent from the diagram S _3,
When a long stroke seek is performed, the seek time becomes longer. This means that reading or writing from the magnetic head 32 is delayed. However, in the case of AV data, a data read or write speed of about several MB per second is currently required, but since a current HDD has a read or write speed of about several tens MB per second, Almost no hindrance.

In the above, the VCM current and the actuator
Example of setting the maximum drive speed of the data 30 according to the seek distance
And the slew rate of the VCM current,
In other words, it is necessary to regulate the rise or fall of the current.
Both are effective for noise reduction. An example is shown in FIG. FIG.
Sets the VCM control condition in two stages, that is, the seek distance
Shows an example in which the seek distance is short.
Control S ₁And when the seek distance is long
Diagram S_TwoIndicated by. Diagram S_TwoAs you can see
If the seek distance is long, the slew rate of the VCM current
Regulations are low. As is well known, current switches
Lowering the rule rate can reduce noise.
Therefore, the diagram S_TwoIn the seek shown, the VCM
Actuate due to shortened flow and its supply time
Noise due to a decrease in the acceleration and maximum drive speed of the motor 30
In addition to reducing the slew rate of the VCM current,
The noise reduction effect is added, and the quietness is further improved.
can do.

Next, the noise levels of the HDD 10 according to the present embodiment and the conventional HDD were measured, and the effect of noise reduction of the present invention was confirmed. The measurement is a standard "JBMS-67" established by the Standard Committee of the Japan Office Machinery Manufacturers Association.
C. The random seek in accordance with “9.3.2 Operation mode” was performed to operate the HDD. The results are shown in the chart of FIG. 5, which shows that the HDD 10 according to the present embodiment is effective in reducing noise in the order of 4 kHz, 2 kHz, and 1 kHz. In the chart of FIG. 5, the column A shows the noise after weighting is applied to each frequency according to the human hearing. Here, it can be seen that the noise level is reduced by about 10 dB as compared with the conventional HDD. In two representative benchmark tests, the HDD 10 according to the present embodiment and the conventional H
DD performance was measured. Benchmark test is WinBench99 Business Diss
k WinMark99 (Winbench 99 Business
Disc Winmark 99, trademark) and WinBen
ch99 HighEnd Disk WinMark9
9 (Winbench 99 High End Disc Winmark 99, trademark) were measured three times each, and the average was also determined. The results are shown in the table of FIG. 6, and it was confirmed that performance almost equivalent to that of the conventional HDD was obtained. From the above, it can be seen that a low-noise HDD can be provided without deteriorating performance.

[0026]

As described above, according to the present invention, A
A disk drive device capable of suppressing generation of noise when recording and reproducing V data and a control method thereof are provided. In particular, the present invention eliminates the need to take measures such as using a special material or attaching a special cover to the housing and cover that constitute the disk drive device, so that a low-noise disk drive device can be provided without increasing costs. It has a remarkable effect that it can be provided. Further, according to the present invention, since performance almost equivalent to that of a conventional disk drive device is obtained, it is possible to sufficiently cope with recording and reproducing AV data.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view of an HDD according to an embodiment.

FIG. 2 is a block diagram showing a configuration of the HDD according to the embodiment.

FIG. 3 is a diagram showing control of a VCM according to the present embodiment, wherein the upper part shows the relationship between the drive time (t) and the drive speed (v), and the lower part shows the relationship between the drive time (t) and the current value. Is shown.

FIG. 4 is a diagram showing control of a VCM according to another embodiment, wherein the upper part shows the relationship between the driving time (t) and the driving speed (v), and the lower part shows the relationship between the driving time (t) and the current value. Show the relationship.

FIG. 5 is a table showing the results of measuring the noise levels of the disk drive according to the present invention and the conventional disk drive.

FIG. 6 is a table showing the results of measuring the performance of a disk drive according to the present invention and a conventional disk drive in two representative benchmark tests.

FIG. 7 shows a VCM in a conventional disk drive device.
Is a diagram showing the control of (a), the upper part shows the relationship between the drive time (t) and the drive speed (v), and the lower part shows the relationship between the drive time (t) and the current value.

[Explanation of symbols]

10: Hard disk drive (HDD), 18: Spindle motor, 22: Magnetic disk, 26: Spacer,
28 ... top clamp, 30 ... actuator, 32 ...
Magnetic head, 34 ... pivot, 36 ... VCM coil, 3
8 Flexible cable (FPC), 40 Lamp
Block, 42 ... Acoustic plate, 44 ... V
CM stator, 46: Voice coil motor (VCM) spindle driver, 48: MPU / (hard disk controller) HDC, 50: MPU, 52: Memory,
54: Servo signal

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Masahiko Sato 1 Kirihara-cho, Fujisawa-shi, Kanagawa F-term in IBM Japan, Ltd. Fujisawa office F-term (reference) 5D088 NN02 NN12 NN25

Claims (13)

[Claims] A spindle motor that rotates at a predetermined rotational speed; a disk-shaped recording medium that is rotated by the spindle motor; a head that reads or writes information recorded on the disk-shaped recording medium; An actuator that seeks on a disk-shaped recording medium and is driven under different control conditions depending on a seek distance. 2. The disk drive device according to claim 1, wherein the actuator drives the head by setting a maximum drive speed according to a seek distance. 3. The disk drive device according to claim 1, wherein the actuator drives the head by setting a current slew rate according to a seek distance. 4. The disk drive according to claim 1, wherein the actuator drives the head by determining a current value according to a seek distance. 5. A voice coil motor for seeking a magnetic head for reading or writing information from / to a magnetic disk, a seek distance detector for detecting a seek distance when the magnetic head seeks, and the seek distance. A controller for a disk drive, comprising: a controller that controls the voice coil motor based on seek distance information obtained by a detector. 6. The magnetic disk on which the magnetic head moves.
The seek distance is defined by the number of cylinders of the disk, and the number of cylinders to which the magnetic head moves during seek is defined.
And the seek distance is S ₁, S_Two, S_Three, ... S_N(However, S
₁<S_Two<S_Three<… <S_N) Is classified into N blocks
The control conditions of the voice coil motor for each block
The controller sets the seek distance information
Report and S₁, S_Two, S_Three, ... S_NCompare the block
According to the control conditions of the voice coil motor of
A contractor characterized by controlling a coil motor.
The control device for a disk drive according to claim 5. 7. The disk drive control device according to claim 6, wherein the seek distance is classified into three blocks of S ₁ , S ₂ , and S ₃ . Wherein said _{S 1, S 2, S 3} , ... S N S 1a acceleration of the voice coil motor in the, S _2a, S _3a, ... When _{S Na, S 1a> S 2a} > S 3a> ... 7. The disk drive control device according to claim 6, wherein the control condition of the voice coil motor is set so as to satisfy> S _Na . 9. A control method of a disk drive device for controlling a seek of a magnetic head when reading information recorded on a magnetic disk or writing information to a magnetic disk, comprising: an actuator according to a seek distance of the magnetic head. The control conditions are set in advance, and the distance when the magnetic head actually seeks is determined,
A method for controlling a disk drive device, comprising controlling the actuator under the control condition corresponding to the distance. 10. The control condition of the actuator is set at least in two stages according to a seek distance, and a maximum seek speed by the actuator is set smaller when the seek distance is longer than when the seek distance is shorter. 10. The method for controlling a disk drive device according to item 9. 11. A limit value of noise caused by a seek is set, a seek distance at which the noise caused by the seek is equal to or less than the limit value, and a control condition of the actuator is set based on the seek distance. Item 10. A method for controlling a disk drive device according to item 9. 12. A control condition of the actuator is set such that a current value supplied to the actuator is larger than another seek distance at a seek distance at which noise due to the seek is equal to or less than the limit value. A method for controlling a disk drive device according to claim 11. 13. A disk-shaped recording medium capable of random access, a head for reading or writing information from / to the recording medium, and an actuator for the head to seek on the recording medium, The actuator includes a voice coil motor, wherein the head controls a frequency of a long seek distance to be lower than a frequency of a short seek distance, and controls a maximum driving speed of the voice coil motor to be lower for a long seek distance than for a short seek distance. The noise reduction when the head randomly seeks on the recording medium is reduced.