JPH1040641A - Disk device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To surely secure the continuity of information under recording and reproducing in the disk device and to reduce the occurrence of a noninformation part of output information at the time of reproducing the information and an unrecordable area on a recording medium at the time of recording information. SOLUTION: Under the state of reading out prescribed information from an MD 1, when it is detected by a main control circuit 12 that a target track is not caught by an optical pickup 3, and afterward, the optical pickup 3 is not in a position to catch up with the target track even after a lapse of a fixed time, whether impact is given to a device main body is judged based on a detecting result by an impact detecting circuit 11. When the impact given to the device main body is judged, a focus servo gain and a tracking servo gain of a servo circuit 5 are increased, and when no impact given to the device main body is judged, the focus servo gain and the tracking servo gain of the servo circuit 5 are decreased, and then after adjusting the gains, catching the target track is tried again.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a disk device using a disk-shaped recording medium for reproducing or recording information.

[0002]

2. Description of the Related Art Conventionally, as a disk device using a disk-shaped recording medium for reproducing or recording information, there is an MD device using a mini-disc (hereinafter, referred to as MD) as a recording medium. A known MD device has a configuration as shown in FIG.
This will be described based on the block diagram shown in FIG.

In FIG. 4, an MD 1 is driven to rotate by a spindle motor 2, and in this rotating state, various information is read from the MD 1 by an optical pickup 3.
Various information is recorded on the MD 1 by the optical pickup 3 and the recording head 4. At this time, the servo circuit 21 outputs a servo output signal based on a servo error signal generated based on the information read by the pickup 3, and drives various actuators for driving the optical pickup 3 and the recording head 4. The pickup 3 and the recording head 4 are held at appropriate positions with respect to the MD 1.

When information recorded on the MD 1 is reproduced, a signal read from the MD 1 by the optical pickup 3 is decoded by a reproduction signal processing circuit 6.
The main control circuit 22 based on the address information of the MD therein
Controls the servo circuit 21 to move the optical pickup 3 to the target track position, and thereafter, reproduces the signal read from the MD 1 by the optical pickup 2 to the reproduction signal processing circuit 6
And extract information from it.

The information extracted at this time is M
Since the information reading speed from D1 is about 1.4 Mbit / s and the external output speed is about 0.3 Mbit / s, it is temporarily stored in the storage circuit 7 for speed adjustment between the two, and then stored. Information is read from the circuit 7 at a predetermined speed and output from the output terminal 8. At this time, the main control circuit 22
Controls each unit so that the reading of information from the MD 1 is performed intermittently so that the amount of information stored in the storage circuit 7 does not exceed the storage capacity and does not become empty.

When information is recorded on the MD1, the information from the input terminal 9 is temporarily stored in the storage circuit 7 for the same reason as described above, and the address information recorded on the MD1 by the optical pickup 3 is stored. The main control circuit 22 controls the servo circuit 21 based on the address information to move the optical pickup 3 and the recording head 4 to the empty track position. The information is read out at a predetermined speed, subjected to predetermined signal processing by a recording signal processing circuit 10 and given to the recording head 4 to apply a magnetic field modulation to the MD 1 and to generate a light beam stronger than that at the time of reproduction from the optical pickup 3. By irradiation, information is recorded on MD1. At this time, the main control circuit 22 controls each unit so as to intermittently write information to the MD 1 so that the amount of information stored in the storage circuit 7 does not exceed the storage capacity and does not become empty. .

In the MD device configured as described above, when reproducing the information recorded on the MD1,
Alternatively, when information is recorded on the MD1, a target track on the MD1 cannot be captured due to an external impact (vibration) to the apparatus main body or a defect or a scratch on the MD1, and the continuity of information in recording / reproduction is lost. Although there is a point, in the MD device configured as described above, by providing the storage circuit 7, continuity of information in recording / reproduction can be maintained for a predetermined period. However, in the MD device configured as described above, if an appropriate measure is not taken during the predetermined period, the continuity of information in recording and reproduction is impaired because the storage capacity of the storage circuit 7 is limited. become.

Therefore, conventionally, Japanese Patent Laid-Open Publication No.
As disclosed in Japanese Patent Laid-Open No. 5 (1999) -2005, there has been proposed an apparatus in which an impact detecting means is provided and a retry of track acquisition is performed based on the detection result. Hereinafter, a description will be given based on a block diagram shown in FIG. I do.

In FIG. 4, when a target track on the MD 1 cannot be captured by the pickup 3 within a preset number of retries or within a predetermined time, the main control circuit 22 performs a track based on the detection state of the impact detection circuit 11. The reason for not being able to capture is determined.
When an impact is detected by the impact detection circuit 11, it is determined that the cause of the inability to catch the track is an impact. When the impact is not detected by the impact detection circuit 11, the cause of the inability to catch the track is a missing or defective MD1. It is determined that it is a scratch.

If the target track cannot be captured while the information recorded on the MD 1 is being reproduced, the main control circuit 22 determines the reason why the track cannot be captured based on the detection state of the impact detection circuit 11. However, if it is determined that the cause is an impact on the main body of the apparatus, the cause is temporary, and there is a high possibility that the track acquisition will succeed by retry. When the main control circuit 22 determines that the cause of the failure to capture the track is a defect or a scratch on the MD1, it is unlikely that the track capture will be successful by the retry. Since there is a high possibility that the data exists on the MD 1 over a wide range, the information storage in the storage circuit 7 becomes empty and the reproduction Since the period in which the interruption becomes longer,
An operation of giving up the acquisition of the original target track, controlling the storage circuit 7 to forcibly nullify (mute) the information to be read from the track, and then capturing the track advanced by a certain amount and reading the information. To continue.

If the target track cannot be captured while the information is being recorded on the MD1, the main control circuit 22 determines the reason why the track cannot be captured based on the detection state of the impact detection circuit 11, If the cause is determined to be an impact on the device main body, the cause is temporary, and there is a high possibility that the track will be captured by retry. If the main control circuit 22 determines that the cause of the inability to capture the track is a defect or a scratch on the MD1, it is unlikely that the track capture will succeed by retrying. Since there is a high possibility that the recorded information exists over a wide range, unless the track acquisition is abandoned immediately, the information storage in the storage circuit 7 exceeds the storage capacity and the recorded information is lost. Because it would be, give up the acquisition of the initial target track to continue the operation to write information to capture a certain amount advanced tracks from the track.

Therefore, according to the above operation control, even if the target track on the MD 1 cannot be captured due to an external impact (vibration) to the apparatus main body or a defect or a scratch on the MD 1, the information stored in the storage circuit 7 is not obtained. Accordingly, appropriate measures can be taken while maintaining the continuity of information in recording / reproduction, and the continuity of information in recording / reproduction can be prevented from being impaired.

[0013]

However, in the above-mentioned conventional apparatus, when it is determined that the cause of the inability to catch the track is an external impact on the apparatus main body, the same track is retried. On the other hand, when an external impact is continuously applied, only the retry of the same track is repeatedly performed, and the information is read from the recording medium and the information is written to the recording medium as long as the external impact does not disappear. Therefore, there has been a problem that appropriate measures cannot be taken during a predetermined period, and continuity of information in recording / reproduction is lost.

Further, in the above-described conventional apparatus, when it is determined that the cause of the inability to capture the track is a defect or a scratch on the recording medium, the capture of the original target track is abandoned, and the track advanced by a certain distance from the track is replaced. In order to read or write information by capturing, even if the loss or scratch on the recording medium is minute, it easily gives up track capture, and the non-information part of the output information during information reproduction, and the information non-information part during information recording. There is a problem that a large number of non-recordable areas are generated on the recording medium.

According to the present invention, the continuity of information during recording / reproduction can be ensured, and the occurrence of non-information portions of output information during information reproduction and the occurrence of non-recordable areas on a recording medium during information recording can be prevented. It is an object of the present invention to provide a disk drive capable of reducing the number of disk drives.

[0016]

In order to achieve the above object, according to the present invention, a track formed on a recording medium is captured by a pickup to reproduce or reproduce information on the track. In a disk device for recording information in a disk drive, a servo means for controlling track pickup by the pickup, a detection means for detecting an external impact applied to the apparatus body, and a gain of the servo means are adjusted based on a detection result by the detection means. And control means for performing the control.

According to a second aspect of the present invention, the control means includes:
When the external impact is detected by the detecting means, the gain of the servo means is increased, and when the external impact is not detected by the detecting means, the gain of the servo means is decreased.

According to a third aspect of the present invention, a storage means for temporarily storing information reproduced from a recording medium or information to be recorded on a recording medium, and a detection means for detecting the amount of information stored in the storage means. The control means determines whether retry of track capture is possible based on the detection result by the detection means and the accumulation amount detected by the detection means when the pickup cannot capture the target track on the recording medium. Is determined, and the servo means is controlled based on the determination result.

According to a fourth aspect of the present invention, there is provided a disk apparatus for capturing a track formed on a recording medium by a pickup and reproducing information on the track or recording information on the track on which the track has been captured. Servo means for controlling the information, storage means for temporarily storing information reproduced from the recording medium or information to be recorded on the recording medium, detection means for detecting the amount of information stored in the storage means, and recording by the pickup. When the target track cannot be captured on the medium,
A control means is provided for judging whether or not retry of track acquisition is possible based on the accumulation amount detected by the detection means, and controlling the servo means based on the judgment result.

Therefore, according to the first aspect of the present invention, the control means adjusts the gain of the servo means based on the detection result of the external impact by the detection means, so that the optimum servo according to the use condition of the apparatus main body. The state can be ensured, and the trouble of track capture can be eliminated.

According to the second aspect of the present invention, when the detection means detects an external impact on the apparatus main body, the control means increases the gain of the servo means, and the detection means does not detect the external impact on the apparatus main body. When
By reducing the gain of the servo means, it is possible to secure an optimal servo state against an external impact on the apparatus main body or a defect or a scratch on the recording medium, and it is possible to solve the problem of track capture.

According to the third aspect of the present invention, when the target track on the recording medium cannot be captured by the pickup, the control means determines whether an external impact on the apparatus body is detected by the detection means, and The detection means detects an external impact on the apparatus main body at this time,
If the accumulated amount detected by the detecting means is larger than a predetermined amount, the control means increases the gain of the servo means, controls the servo means to retry the track acquisition, and uses the detecting means to detect the main body of the apparatus. If no external impact is detected and the amount of accumulation detected by the detecting means is larger than a predetermined amount, the control means reduces the gain of the servo means and controls the servo means to retry the track acquisition. If the accumulated amount detected by the detecting means is smaller than the predetermined amount, the control means gives up capturing the original target track regardless of the detection result by the detecting means, controls the servo means, and controls the servo means to keep the target track constant. By capturing the advanced track, the optimal servo state against external impacts on the device body and defects and scratches on the recording medium Can coercive, it is possible to solve a problem of track capture, it is possible to prevent such reproduction information and recording information is interrupted.

According to the fourth aspect of the present invention, when the target track on the recording medium cannot be captured by the pickup, the control means recognizes the accumulated amount detected by the detection means, and at this time, the detection amount is detected by the detection means. If the accumulated amount is larger than the predetermined amount, the control means controls the servo means to retry the track acquisition, and if the accumulated amount detected by the detecting means is smaller than the predetermined amount, the control means By giving up the capture of the target track and controlling the servo means to capture the track that has advanced by a certain amount from the track, it is possible to prevent the reproduction information and the record information from being interrupted.

[0024]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a schematic functional block diagram showing an electrical configuration of an MD device showing an embodiment of a disk device according to the present invention.
FIG. 2 is a flowchart showing a track capturing operation control during information reproduction in the MD device, and FIG. 3 is a flowchart showing a track capturing operation control during information recording in the MD device.

In FIG. 1, the same parts as those in FIG. 4 are denoted by the same reference numerals, and description thereof will be omitted.

In FIG. 1, a servo circuit 5 is capable of adjusting a focus servo gain and a tracking servo gain based on control by a main control circuit 12.
The main control circuit 12 controls the servo circuit 5 based on the accumulation amount of the storage circuit 7 and the detection result of the shock detection circuit 11 so as to perform gain adjustment and retry the track pickup by the optical pickup 3.

First, a description will be given of a track capturing operation at the time of reproducing information in the MD device configured as described above with reference to a flowchart shown in FIG.

When the user operates an operation unit (not shown) to instruct reproduction of predetermined information in the MD 1 mounted on the apparatus main body, the main control circuit 12 controls the servo circuit 5, and the servo circuit 5 controls the optical pickup 3. The optical pickup 3 is driven to read information from a predetermined recording area (TOC area) of the MD 1, the signal read from the optical pickup 3 is decoded by the reproduction signal processing circuit 6, and the main control circuit 12 converts the address information of the information. By recognizing the track position of the predetermined information instructed to be reproduced by the user on the basis of the information, the servo circuit 5 is controlled to drive the optical pickup 3 so that the optical pickup 3 catches and follows the target track, so that the predetermined information from the MD 1 read out.

While the predetermined information is being read from the MD 1 in this manner, the target track is not captured by the optical pickup 3, and thereafter, the optical pickup 3 captures the target track despite a certain period of time. When the main control circuit 12 detects that the storage amount cannot be stored (step F1), the main control circuit 12 determines whether the storage amount of the storage circuit 7 is larger than a predetermined amount (step F2).

The predetermined amount is set to a value larger than the amount of information read from the storage circuit 7 during the time required for retrying the track capture by the optical pickup 3.

When the main control circuit 12 determines at this time that the storage amount of the storage circuit 7 is larger than the predetermined amount (step F2), the main control circuit 12 determines the main body of the apparatus based on the detection result by the shock detection circuit 11. It is determined whether or not an impact has been applied to (step F3).

At this time, when the main control circuit 12 determines that a shock is applied to the apparatus body based on the detection result of the shock detection circuit 11 (step F3), the main control circuit 12 controls the servo circuit 5 The control is performed to increase the focus servo gain and the tracking servo gain of the servo circuit 5 (step F4), and retry acquisition of the target track (step F5).

On the other hand, the main control circuit 12
When the main control circuit 12 determines that no impact has been applied to the apparatus main body based on the detection result by (step F3), the main control circuit 12 controls the servo circuit 5 to reduce the focus servo gain and the tracking servo gain of the servo circuit 5. (Step F6), and retried the acquisition of the target track (Step F5).

The reason why the gain is increased when an impact is applied to the apparatus main body and the gain is decreased when no impact is applied to the apparatus main body is generally related to track capture of an optical disk. When the focus servo gain and the tracking servo gain are increased (the gain intersection frequency is increased),
It is advantageous for external impact, but disadvantageous for the loss or scratch of the disc. Conversely, if the focus servo gain and the tracking servo gain are reduced (gain intersection frequency is reduced), Although it is disadvantageous, it is advantageous for loss or damage of the disk.

On the other hand, the main control circuit 12 determines that the storage amount of the storage circuit 7 is smaller than a predetermined amount (step F2).
Then, the main control circuit 12 controls the storage circuit 7 so that information to be read from the track is made non-information (step F).
7) At the same time, the servo circuit 5 is controlled so that the optical pickup is captured by a track that has advanced by a certain amount from the target track (step F8).

Therefore, according to the above operation control, even if the optical pickup 3 inadvertently misses the target track in the MD 1 due to an impact on the apparatus main body or a defect or a scratch in the MD 1 during information reproduction, the target track is not taken care of. In addition, the servo circuit 5 can be accurately controlled based on the cause of the departure of the target track to more reliably capture the target track, and the period during which the reproduction information is interrupted can be minimized.

Next, a track capturing operation at the time of recording information will be described with reference to a flowchart shown in FIG.

When the user inputs information to the input terminal 9 and instructs recording of the input information to the MD 1 mounted on the apparatus main body by operating an operation unit (not shown), the main control circuit 1
2 controls the servo circuit 5, and the servo circuit 5 drives the optical pickup 3 to read information from a predetermined recording area (TOC area) of the MD 1, and converts a signal read from the optical pickup 3 into a reproduction signal. The decoding is performed by the processing circuit 6, and the main control circuit 12 recognizes the track position of the empty area based on the address information, and controls the servo circuit 5 to drive the optical pickup 3 to catch the target track and follow it. By doing so, predetermined information is written to the MD1.

In the state where the input information is written in the MD 1 in this manner, the target track is not captured by the optical pickup 3 and thereafter, the optical pickup 3 cannot capture the target track despite the lapse of a fixed time. When this is detected by the main control circuit 12 (step F11), the main control circuit 12 determines whether or not a shock is applied to the apparatus body based on the detection result of the shock detection circuit 11 (step F12).

At this time, the main control circuit 12 determines that a shock has been applied to the apparatus body based on the detection result by the shock detection circuit 11 (step F12).
The main control circuit 12 includes the servo circuit 5 and the recording signal processing circuit 1
0, the recording operation is interrupted (step F13).

At this time, the display unit (not shown) is used to warn the user that the information has not been recorded due to the impact applied to the apparatus main body, and to evacuate the apparatus main body from the impact environment before the information is interrupted. If the user is urged to take measures, or if the device reproducing the information recorded on the MD1 is interruptible, until the impact stops,
The interruption of the information may be prompted, or the device may be controlled to interrupt the information.

On the other hand, the main control circuit 12
When the main control circuit 12 determines that no impact is applied to the apparatus main body based on the detection result (step F12), the main control circuit 12 determines whether or not the remaining storage amount of the storage circuit 7 is larger than a predetermined amount (step F14). .

The predetermined amount is set to a value larger than the amount of information written in the storage circuit 7 during the time required for retrying the track capture by the optical pickup 3.

When the main control circuit 12 determines at this time that the storage remaining amount of the storage circuit 7 is larger than the predetermined amount (step F14), the main control circuit 12 controls the servo circuit 5 and The focus servo gain and the tracking servo gain are reduced (step F15), and the target track is retried (step F1).
6).

The reason why the gain is reduced when no impact is applied to the main body of the apparatus is to generally increase the focus servo gain and the tracking servo gain with respect to the track capture of the optical disc (increase the gain intersection frequency). This is advantageous for extraneous impact, but disadvantageous for loss or damage of the disk. Conversely, the focus servo gain and the tracking servo gain are reduced (the gain intersection frequency is reduced).
This is disadvantageous against external impact, but is advantageous against loss or damage of the disk.

Further, the main control circuit 12 determines that the storage remaining amount of the storage circuit 7 is smaller than a predetermined amount (step F14).
Then, the main control circuit 12 controls the servo circuit 5 to cause the optical pickup to be captured by a track that has advanced by a certain amount from the target track (step F17).

Therefore, according to the above-described operation control, even if the target track is inadvertently detached due to an impact on the apparatus main body during information recording, the already recorded information or the optical pickup 3 may be erroneously destroyed. Even if the optical pickup 3 inadvertently misses the target track in the MD 1 due to a defect or scratch in the MD 1, the servo circuit can be accurately determined based on the cause of the miss in the target track. 5 can be controlled to more reliably capture the target track, and the occurrence of a non-recordable area on the MD 1 can be minimized.

[0049]

As described above, according to the first or second aspect of the present invention, by adjusting the servo gain on the basis of the presence or absence of an external impact, it is possible to prevent the external impact on the apparatus main unit, the loss in the recording medium, and the like. Optimum servo status against scratches can be ensured, and track capture problems can be eliminated, so that even if an external impact is continuously applied, the continuity of information in recording and reproduction is reliably maintained. In addition, it is possible to reduce the occurrence of a non-information portion of output information during information reproduction and a non-recordable area on a recording medium during information recording.

According to the third aspect of the invention, by adjusting the servo gain and performing retry control of the track acquisition based on the presence or absence of an external impact and the storage amount of the stored information, the external impact or recording on the apparatus main body is performed. It is possible to secure the optimal servo state for the loss or scratch on the medium, to solve the problem of track capture, and to prevent the reproduction information and recording information from being interrupted. Even if they are continuously added, the continuity of information during recording / reproduction can be reliably maintained, and the non-information portion of the output information during information reproduction and the non-recordable area on the recording medium during information recording are reduced. Occurrence can be reduced.

According to the fourth aspect of the present invention, it is possible to prevent the reproduction information and the recording information from being interrupted by performing the retry control of the track acquisition based on the storage amount of the storage information. Therefore, even if an external impact is continuously applied, the continuity of information in recording / reproduction can be reliably maintained.

[Brief description of the drawings]

FIG. 1 is a schematic functional block diagram showing an electrical configuration of an MD device showing an embodiment of a disk device according to the present invention.

FIG. 2 is a flowchart showing a track capturing operation control at the time of reproducing information in the MD device.

FIG. 3 is a flowchart showing a track capturing operation control during information recording in the MD device.

FIG. 4 is a schematic functional block diagram showing an electrical configuration of an MD device showing a conventional example of a disk device.

[Explanation of symbols]

 Reference Signs List 1 MD 2 spindle motor 3 optical pickup 4 recording head 5 servo circuit 6 playback signal processing circuit 7 storage circuit 8 output terminal 9 input terminal 10 recording signal processing circuit 11 shock detection circuit 12 main control circuit

Claims (4)

[Claims] 1. A disk device that captures a track formed on a recording medium by a pickup and reproduces information on the track or records information on the track on which the information has been captured. A disk device, comprising: a detection unit for detecting an external impact applied to a device main body; and a control unit for adjusting a gain of the servo unit based on a detection result by the detection unit. 2. The control means increases the gain of the servo means when the external impact is detected by the detection means, and decreases the gain of the servo means when the external impact is not detected by the detection means. 2. The disk drive according to claim 1, wherein 3. A storage means for temporarily storing information reproduced from a recording medium or information to be recorded on a recording medium, and a detection means for detecting an amount of information stored in the storage means, wherein the control means comprises: When the target track cannot be captured on the recording medium by the pickup, it is determined whether or not retry of the track capture is possible based on the detection result by the detection means and the accumulation amount detected by the detection means. 3. The disk device according to claim 1, wherein the servo unit is controlled based on a result. 4. A disk device for capturing a track formed on a recording medium by a pickup and reproducing information on the track or recording information on the track on which the information has been captured, servo means for controlling track capture by the pickup. Storage means for temporarily storing information reproduced from the recording medium or information to be recorded on the recording medium; detection means for detecting the amount of information stored in the storage means; and capturing of a target track on the recording medium by the pickup. Control unit that determines whether or not retry of track capture is possible based on the accumulation amount detected by the detection unit and that based on the determination result, and that the control unit controls the servo unit based on the determination result. Characteristic disk device.