JPH1173719A - Optical disk drive having vibration detection function, method of driving optical disk by optical disk drive, and method of detecting vibration in optical disk drive - Google Patents

Abstract

(57) [Problem] To provide a vibration detecting device capable of detecting the magnitude of vibration generated due to rotation of an optical disk by a simple method, and an optical disk drive using the vibration detecting device. Is the challenge. SOLUTION: By setting a servo gain in a servo control unit 9 to a low value in advance, a state in which a tracking error easily occurs is set, and the optical disk 1 is driven to rotate at the highest rotational speed. Then, a tracking error signal of a predetermined level or more is generated by the vibration generated with the rotation of the optical disk, and when the vibration detection signal is generated, the rotation speed is switched to a one-step slower rotation speed. While repeating this, the rotation speed at which the vibration detection signal is not generated is detected, and the optical disk 1 is driven using this speed as the set rotation speed. As a result, the disk can be driven to rotate at a rotation speed at which vibration causing noise or the like does not occur automatically.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an optical disk drive having a vibration detecting function, a method of driving an optical disk by the optical disk drive, and a method of detecting vibration in the optical disk drive.

[0002]

2. Description of the Related Art As a recording medium for storing application software and the like used in a personal computer, a compact desk (a compact disk) is used instead of a conventionally used floppy disk, taking advantage of the convenience of handling and the large storage capacity. CD-ROMs) have been widely adopted. This CD-ROM has a diameter of 12
The track is composed of a large number of pits and is formed in a spiral shape at minute intervals on a signal recording surface, and information is recorded through the pits. Then, by irradiating a laser beam from the optical pickup provided in the optical disk drive toward the recording surface of the disk and detecting a change in the light intensity of the reflected light, it is possible to read information recorded on the disk. it can.

In an optical disk drive for driving and reproducing such a CD-ROM, the irradiation position of a laser beam from an optical pickup is a spiral track (pit).
It is equipped with a tracking servo mechanism to prevent the optical pickup from deviating from the optical pickup. Controlling.

On the other hand, recently, in order to increase the data transfer speed when reading data from a CD-ROM, the rotation speed of an optical disk has been increased, and for example, high speed such as 8 × speed and 12 × speed has been proposed. An optical disk drive capable of rotating an optical disk by using the same has been put to practical use.

When the optical disk is driven at such a high speed, the time required for reading can be reduced, but on the other hand, a large vibration is generated even by a slight eccentricity of the optical disk which is not a problem in the case of low-speed rotation.
Tracking servo control with higher accuracy is required. Therefore, in an optical disk drive capable of rotating the optical disk at such a high speed, the gain in the tracking servo control is increased to perform the tracking servo control with higher accuracy, and even if a large vibration occurs, the light is reliably emitted. The laser beam emitted from the pickup can be applied to the pits of the optical disk.

However, if such a large vibration occurs when the optical disk rotates at a high speed, the servo control of the optical pickup operates reliably, but the vibration causes the housing of the disk drive to resonate and generate noise.
The vibration is transmitted to the PC system through the housing, which may cause a malfunction. In particular, when a defective disk with poor dimensional accuracy is reproduced, an extremely large vibration is generated, so that such a problem becomes conspicuous.

Therefore, in order to solve such a problem, a vibration measuring device such as a vibration sensor is installed at an appropriate position of the optical disk drive, and the optical disk is driven so that the vibration generated by the rotation of the optical disk does not exceed a reference value. Methods for controlling the rotational speed have been devised.

However, in this method, it is necessary to further install a vibration measuring device in the optical disk drive, and there is another problem that the cost is increased and the number of parts is increased.

[0009]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems in the conventional optical disk drive, and an object of the present invention is to provide a simple method for oscillating the optical disk drive. It is an object of the present invention to provide an optical disk drive having a vibration detection function capable of detecting occurrence of a vibration.

Another object of the present invention is to reduce the number of rotations of an optical disk automatically to a level at which such vibrations do not occur when large vibrations are generated by rotating the optical disk at high speed. To provide an optical disk drive method for driving an optical disk by using the optical disk drive method.

[0011]

In order to achieve the above object, an optical disk drive having a vibration detecting function according to the present invention comprises a spindle for rotating an optical disk placed on a turntable at a plurality of rotational speeds. A motor, an optical pickup that irradiates a beam onto the recording surface of the optical disk and receives the reflected light, a servo control unit that controls the beam emitted from the optical pickup to follow a track on the optical disk recording surface, Servo gain adjustment means capable of adjusting the accuracy of the servo control means,
Error detecting means for detecting when a tracking error has occurred, and rotating the spindle motor in a state where the gain in the servo gain adjusting means is lowered, and the level of the tracking error signal detected by the error detecting means is set to a predetermined value. Vibration detecting means for detecting vibration due to rotation of the optical disk based on a vibration detection signal generated when the value exceeds the value.

In the optical disk drive having the vibration detecting function of the present invention configured as described above, the gain of the tracking servo is set to a low value in advance, and the optical disk is driven in this state, and the vibration detection signal is generated. If this occurs, it is determined that the vibration greater than a predetermined magnitude due to the rotation of the optical disk is occurring, while if no vibration detection signal is generated, the magnitude of the vibration is determined to be less than the predetermined magnitude I do. This makes it possible to detect the magnitude of the vibration generated with the rotation of the optical disk without installing a vibration detecting device such as a vibration sensor.

In the optical disk drive of the present invention, when vibration is detected by the vibration detecting means, the rotation speed of the optical disk is changed and the spindle motor is rotated at a rotation speed at which the magnitude of the vibration is equal to or less than a predetermined value. Can be rotated to drive the optical disc.

Thus, it is possible to automatically set the number of revolutions at which vibration causing noise or the like does not occur, and to rotate the optical disc, thereby preventing the occurrence of noise or the like caused by the vibration. .

In this case, it is possible to change the rotation of the spindle motor from a high-speed rotation to a low-speed rotation sequentially, search for a maximum rotation speed at which generation of a vibration detection signal is not detected, and drive the optical disk at this rotation speed. preferable.

Also, the rotation of the spindle motor may be sequentially changed from low-speed rotation to high-speed rotation to find the maximum rotation speed at which generation of a vibration detection signal is not detected, and drive the optical disc at this rotation speed.

Further, the method for driving an optical disk according to the present invention comprises:
A spindle motor for rotating the optical disc mounted on the turntable at a plurality of rotational speeds, an optical pickup for irradiating the recording surface of the optical disc with a beam and receiving the reflected light thereof, and irradiating from the optical pickup A method of driving an optical disk in an optical disk drive, comprising: a servo control unit that controls the beam to follow a track on an optical disk recording surface; and a servo gain adjustment unit that can adjust the accuracy of the servo control unit. A first step of setting the servo gain in the gain adjusting means to a reduced state, and setting the rotation speed of the spindle motor to high-speed rotation, and when a vibration detection signal is generated at the start of rotation, the rotation speed of the spindle motor is reduced. And the second step of sequentially reducing the vibration detection signal The rotational speed Tsu a set rotation speed,
A third step of driving the optical disk by rotating the spindle motor at the set rotation speed.

Another method of driving an optical disk according to the present invention comprises a spindle motor for rotating an optical disk placed on a turntable at a plurality of rotational speeds, a method of irradiating a beam onto a recording surface of the optical disk, An optical pickup for receiving reflected light, servo control means for controlling the beam emitted from the optical pickup to follow a track on an optical disk recording surface, and servo gain adjusting means for adjusting the accuracy of the servo control means; ,
A method for driving an optical disk in an optical disk drive device comprising: a first step of setting the gain of said gain adjusting means to a reduced state; When no detection signal is generated, a second step of sequentially increasing the rotation speed of the spindle motor, and when the generation of a vibration detection signal is detected, the rotation speed one step lower than this rotation speed is set to the set speed. And a third step of driving the optical disc by rotating the spindle motor at the set speed.

Still another aspect of the present invention is characterized in that the optical disk is rotated by lowering the gain of the tracking servo and the occurrence of vibration in the optical disk drive is detected based on whether or not a vibration detection signal is generated. The present invention relates to a method for detecting vibration in an optical disk drive.

Another aspect of the present invention is characterized in that the optical disk is rotated by lowering the servo gain of the optical pickup, and the occurrence of vibration in the optical disk drive is detected based on whether or not a vibration detection signal is generated. The present invention relates to a method for detecting a vibration in an optical disk drive device that performs the operation.

Other objects, configurations and effects of the present invention will become more apparent from the following description of the embodiments with reference to the drawings.

[0022]

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

FIG. 1 is a block diagram showing the configuration of an optical disk drive according to one embodiment of the present invention. As shown in FIG. 1, the optical disk drive generally includes a spindle motor 2 for driving an optical disk 1 such as a compact disk (CD-ROM) to rotate at a predetermined rotation speed, and a predetermined rotation toward a signal recording surface of the optical disk 1. An optical pickup 3 for irradiating a laser beam having a wavelength of .lambda. And receiving the reflected light reflected on the recording surface;
, A pickup feed mechanism 4 that slides in the radial direction, an RF amplifier 5 that amplifies a signal received by the optical pickup 3, and a CD signal processing unit that performs EFM demodulation and the like on the signal output from the RF amplifier 5. 6
If the obtained signal is an audio signal, the D / A converter 7 converts the signal into an analog signal and outputs it to a subsequent audio signal processing system, an error amplifier 8, a servo control unit 9, a CD-ROM decoder 10 and CPU 11
, Interface 12 and servo gain adjustment unit 13
And a driver 14.

The error amplifier 8 amplifies a tracking error signal detected when the laser beam emitted from the optical pickup 3 deviates from the track of the optical disk 1 and outputs the signal to the CPU 11. Servo control unit 9
Performs servo control of the optical pickup, such as tracking control and focus control, so that the beam emitted from the optical pickup 3 can reliably follow the track of the optical disk 1 even when vibration occurs when the optical disk 1 is driven. Things. CD-ROM decoder 10
Performs a header detection, an ECC (error correction code) decoding, and the like on the EFM signal obtained by the CD signal processing unit 6, and outputs the signal to the interface 12. The servo gain adjustment unit 13 adjusts the value of the servo gain in the servo control unit 9 appropriately according to a command from the CPU 11.

The CPU 11 operates as a control center of the optical disk drive. The CPU 11 supplies a control command signal to the servo controller 9 and the CD-ROM decoder 10, and controls the rotation speed of the spindle motor 2 according to a procedure described later. It is controlled so as to be optimal.

The driver 14 actually outputs a drive signal to the spindle motor 2, the optical pickup 3, and the pickup feed mechanism 4. This spindle motor 2 is controlled by a control signal from a driver 14.
The rotation speed can be changed in multiple stages. For example, in the case of an optical disk drive capable of rotating at a high speed of 12 ×, a plurality of rotation speeds such as 12 ×, 10 ×, 8 ×, 6 ×, 4 ×, 2 ×, and 1 × can be set. Can be.

Next, the operation of the first example of the optical disk drive according to the present embodiment configured as described above will be described with reference to the flowchart shown in FIG.

When the optical disk 1 is inserted into the optical disk drive, first, the servo gain in the servo controller 9 is automatically adjusted (step 1). Next, the type of the optical disk is determined by reading the TOC recorded on the innermost side of the optical disk 1 (Step 2), and the disk size is further determined (Step 3). Thereafter, the CPU 11 initializes the spindle motor 2
Is set to the maximum speed, and this control signal is output to the driver 14 (step 4). For example, when the optical disk drive can drive at a maximum speed of 12 times, the rotation speed of the spindle motor 2 is set to this 12 times speed. Further, the servo gain set in the servo control unit 9 is reduced from the initially set value via the servo gain setting unit 13 to a predetermined value (step 5). That is, in this state, sufficient servo control is not performed, and a tracking error is likely to occur due to vibration generated by rotation of the optical disc 1 or the like.

Then, in this state, the spindle motor 2 is rotated at a high speed, and reading (reproduction) is performed by the optical pickup 3. In this case, when a large vibration occurs due to the dimensional accuracy of the optical disc 1, the level of the tracking error signal exceeds a predetermined value, and a vibration detection signal is generated. In other words, if the servo gain is set to such an extent that it can follow high-speed rotation, even if such a large vibration occurs due to high-speed rotation, it is possible to follow it reliably, and the level of the tracking error signal falls below a predetermined value. Although no detection signal is generated, as described above, the servo gain is set to a low value in advance, so that if the spindle motor 2 rotates at a high speed and large vibration occurs, the level of the tracking error signal is set in advance. Exceeds a predetermined value, and a vibration detection signal is generated.

If such a vibration detection signal is generated within a predetermined time after driving (Y in step 6).
ES), this is detected by the error amplifier 8 shown in FIG. 1, and upon receiving this signal, the CPU 11 performs control to reduce the rotation speed of the spindle motor 2 (step 8). For example, when a vibration detection signal is generated at 12 × speed, a signal for decelerating to 8 × speed is output to the driver 14 and the rotation speed is set to 8 × speed. Similarly, the optical disc 1 is rotated at this rotation speed, and it is again determined whether or not a vibration detection signal is generated. If a vibration detection signal is generated, an operation of sequentially reducing the rotation speed is performed. Does not occur (NO in step 6),
The optical disk 1 is actually driven at this speed by setting this rotation speed to a standby speed (step 7).

Thus, the vibration generated by the rotation of the optical disk 1 can be made smaller than a certain fixed value, so that not only the tracking error at the time of driving the rotation of the optical disk can be prevented but also the rotation of the optical disk 1 The magnitude of the vibration can be regulated to such an extent that noise does not occur.

As described above, in the present embodiment, the servo gain in the servo control means 9 is previously set low so that a tracking error is likely to occur, and when the spindle motor 2 is rotated, a vibration detection signal is generated. The magnitude of the vibration is detected depending on whether or not it occurs. In other words, if a vibration detection signal is generated, it means that a vibration equal to or greater than the set value has occurred. On the other hand, if no vibration detection signal is generated, it can be said that the magnitude of the vibration is equal to or smaller than the set value.

Therefore, by changing the rotation speed of the spindle motor 2 from high-speed rotation to low-speed rotation in order to find a rotation speed at which a vibration detection signal is no longer generated, and driving the optical disc 1 at this rotation speed, a tracking error can be obtained. Since it is possible to prevent the occurrence of the noise and to suppress the magnitude of the vibration accompanying the rotation of the optical disk 1 to a predetermined value or less, it is possible to prevent the rotation of the optical disk from causing noise or the like. Become. Accordingly, the vibration value can be reduced to the reference value or less without using a separate vibration measuring device, so that the cost is low and the number of parts can be reduced.

Next, a second embodiment of the present invention will be described. In the above-described first embodiment, the method of determining the generation of the vibration detection signal while sequentially changing the rotation speed of the spindle motor 2 from the maximum speed to the low speed is used. In the second embodiment, the method shown in FIG. As described above, the initial speed is set to the minimum speed, and the maximum speed at which no vibration detection signal is generated is searched for while sequentially increasing the rotation speed.
Then, the disk is reproduced by returning to the level of the rotation speed one step lower than the level of the rotation speed at which the vibration detection signal is detected.

That is, as shown in FIG. 3, in the second embodiment, steps 11 (ST11) to 1
Up to 3 (ST13) is the same as in the first embodiment shown in FIG. 2, but the rotation speed of the spindle motor 2 is set to the minimum speed in step 14 (ST14). Then, the servo gain is lowered (ST15) and the disk is rotated. In this state, it is determined whether or not a vibration detection signal is generated. If no vibration detection signal is generated (step 16)
NO), the number of revolutions of the spindle motor 2 is increased by one step (step 17). This routine is repeated until the generation of the vibration detection signal is detected in step S16. If the generation of the vibration detection signal is detected in step 16 (YES in step 16), the spindle motor 2
The number of rotations is lowered by one step (step 18), and the disk is reproduced with the rotation speed set as the set rotation speed (step 19).

Also in the method of the second embodiment, it is possible to reproduce the disk at a vibration level that does not cause noise or the like.

In the first and second embodiments, the level of the vibration to be detected can be appropriately set by adjusting the manner of decreasing the servo gain. It goes without saying that the level of the tracking error signal for determining that the vibration detection signal has occurred can also be set as appropriate.

In the first and second embodiments, the level of the tracking error signal is detected, and it is determined that the vibration detection signal is generated when the level exceeds a predetermined value. If the signal is affected by the accompanying vibration, such a vibration detection signal can be obtained based on other signals. For example, instead of the tracking error signal, the gain of the focus servo can be lowered to obtain such a vibration detection signal based on the focus error signal. In this case, the vibration in the rotational axis direction of the disk can be effectively reduced. Can be detected.

Further, in the first and second embodiments described above, a compact disc (CD) is used as the optical disc 1.
Has been described as an example, but the present invention is not limited to this, and a recordable / reproducible CD-R, CD-RW,
The present invention can be applied to various types of optical disks such as DVD (digital video disk), which can be driven by changing the rotation speed.

Finally, the present invention is not limited to the embodiments described above, and it goes without saying that various improvements and modifications are possible within the scope of the following claims.

[0041]

As described above, according to the present invention,
The servo gain is set low in advance, the optical disk drive is operated in this state, and a vibration detection signal is detected based on whether or not the level of a tracking error signal from the optical pickup exceeds a predetermined value. , It is determined whether or not the occurrence of the vibration and the magnitude thereof are equal to or higher than a predetermined level. Therefore, it is possible to determine the magnitude of the vibration generated at the time of rotating the optical disk without using a separate vibration measuring device, so that the cost is low and the number of parts can be reduced.

Further, since the magnitude of the vibration caused by the rotation of the optical disk can be suppressed to a predetermined value or less, noise may be generated by the rotation of the optical disk, and the vibration may be transmitted to the computer side to cause a malfunction or the like. Can be prevented.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of an optical disk drive according to an embodiment of the present invention.

FIG. 2 shows a first example of the optical disk drive according to the present embodiment.
The flowchart figure which shows the operation | movement of an Example.

FIG. 3 shows a second example of the optical disk drive according to the embodiment.
The flowchart figure which shows the operation | movement of an Example.

[Explanation of symbols]

 Reference Signs List 1 optical disk 2 spindle motor 3 optical pickup 4 feed mechanism 5 RF amplifier 6 CD signal processing unit 7 D / A converter 8 error amplifier 9 servo control unit 10 CD-ROM decoder 11 CPU 12 interface 13 gain adjustment unit 14 driver

Claims (8)

[Claims] A spindle motor for rotating an optical disc mounted on a turntable at a plurality of rotational speeds; an optical pickup for irradiating a beam on a recording surface of the optical disc and receiving reflected light thereof; Servo control means for controlling the beam emitted from the pickup to follow the track on the recording surface of the optical disc; servo gain adjustment means for adjusting the accuracy of the servo control means; detecting a tracking error when it occurs An error detecting means for detecting the vibration, and a vibration detection signal generated when the level of the tracking error signal detected by the error detecting means exceeds a predetermined value by rotating the spindle motor with the gain of the servo gain adjusting means lowered. Vibration detection that detects the vibration due to the rotation of the optical disk based on the And means,
An optical disk drive device having a vibration detection function, comprising: 2. When the vibration is detected by the vibration detecting means, the rotational speed of the optical disk is changed, and the optical disk is driven by rotating the spindle motor at a rotational speed at which the magnitude of the vibration is equal to or less than a predetermined value. 2. The optical disk drive according to claim 1, wherein the drive is performed. 3. The method according to claim 1, wherein the rotation of the spindle motor is sequentially changed from high-speed rotation to low-speed rotation, a maximum rotation speed at which generation of a vibration detection signal is no longer detected, and the optical disk is driven at this rotation speed. Claim 2
An optical disk drive as described in the above. 4. The method according to claim 1, wherein the rotation of the spindle motor is sequentially changed from low-speed rotation to high-speed rotation, a maximum rotation speed at which generation of a vibration detection signal is not detected is searched, and the optical disk is driven at this rotation speed. 3. The optical disk drive according to claim 2, wherein: 5. A spindle motor for rotating an optical disc placed on a turntable at a plurality of rotational speeds, an optical pickup for irradiating a recording surface of the optical disc with a beam and receiving reflected light thereof, and Servo control means for controlling the beam emitted from the pickup to follow the track on the optical disk recording surface,
A method for driving an optical disk in an optical disk drive device, comprising: a servo gain adjusting unit capable of adjusting the accuracy of the servo control unit; and a first step of setting a servo gain in the servo gain adjusting unit to a reduced state. Setting the rotation speed of the spindle motor to high-speed rotation,
When a vibration detection signal is detected at the start of rotation, a second step of sequentially reducing the rotation speed of the spindle motor, and a rotation speed at which the vibration detection signal is no longer detected is set as a set rotation speed. A third step of driving the optical disc by rotating the spindle motor. 6. A spindle motor for rotating an optical disc mounted on a turntable at a plurality of rotational speeds, an optical pickup for irradiating a recording surface of the optical disc with a beam and receiving a reflected light thereof, and Servo control means for controlling the beam emitted from the pickup to follow the track on the optical disk recording surface,
A method for driving an optical disk in an optical disk drive device, comprising: a servo gain adjusting unit capable of adjusting the accuracy of the servo control unit; and a first step of setting the gain in the servo gain adjusting unit to a reduced state. Setting the rotation speed of the spindle motor to low speed rotation,
If a vibration detection signal is not detected at the start of rotation, a second step of sequentially increasing the rotation speed of the spindle motor, and if a vibration detection signal is detected, a rotation speed one step lower than this rotation speed is set. And a third step of driving the optical disk by setting the set speed and rotating the spindle motor at the set speed. 7. A method for detecting vibration in an optical disk drive, comprising: lowering the gain of a tracking servo, rotating the optical disk, and detecting the occurrence of vibration in the optical disk drive based on whether a vibration detection signal is generated. 8. A method for detecting vibration in an optical disk drive, comprising: lowering a servo gain of an optical pickup, rotating the optical disk, and detecting the occurrence of vibration in the optical disk drive based on whether a vibration detection signal is generated. .