JPH1116243A - Search of disk player - Google Patents

Abstract

PROBLEM TO BE SOLVED: To evade excessive rise of the inside temperature and to prevent the deterioration of control ability of an integrated circuit by operating the search while reducing the speed of a spindle motor when the objective position exists at the outer peripheral side than the present position and making to operate the search while keeping the spindle motor to the free run state when the objective position exists at the inner peripheral side than the present position. SOLUTION: In the case the search is operated at a high reading out speed such as six times, eight times, etc., against a stipulated linear speed as the reading out speed of a disk signal, the speed reduction to lower the rotating speed of the spindle motor 3 is carried out when the objective position exists at the outer peripheral side than the present position. When the objective position exists at the inner peripheral side, the accelerating operation to increase the rotating speed of the spindle motor 3 is not carried out, and an optical pickup 4 is moved to the objective position keeping the state unsupplying a driving signal, which is called as the free run. Thus, the rotating speed is controlled by a synchronizing signal outputted from the disk 1 when the signal reading out operation is started.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for searching a disk player configured to read out a signal recorded on a disk rotating at a constant linear velocity by an optical pickup.

[0002]

2. Description of the Related Art A disk player which performs a reproducing operation by reading out a signal from a disk on which information data such as music is recorded by a digital signal using an optical pickup has become widespread. One of them is a CD player.

As is well known, a disc used in such a CD player is called a sub-coding signal in which one block is completed at a period of 1/75 second in addition to a main data signal such as music information. A sub data signal is recorded. Such subcoding signals are P, Q to W
The P channel includes position index information indicating the position of the beginning of the song, and the Q channel includes the absolute elapsed time from the start of the signal track, the elapsed time for each song, and the Q channel. Position index information indicating a song number or the like is included.

[0004] Therefore, the CD player can perform an operation of detecting a position where a desired song or the like is recorded by using the position index information and performing a reproducing operation, that is, an operation called a search. Have been.
Such a search operation is performed by moving the optical pickup in the radial direction of the disc, and such a movement operation is an operation of moving the main body of the pickup at a high speed to near the target position, that is, a pickup feeding operation and an optical movement. It is configured to perform the operation by displacing the objective lens constituting the type pickup, that is, the track jump operation.

Recently, a CD called a CD-ROM for reproducing a data signal used for a computer, not a sound signal of music or the like, is reproduced.
-Disk players called ROM players are widespread.

[0006]

The search operation in the disc player is performed by calculating the number of tracks from the absolute time of the current position and the absolute time of the target position to the target position, and using the optical pickup in accordance with the number of tracks. The rotation is performed by moving the disk, and when the movement is performed, the rotation speed of the spindle motor for driving the disk is controlled to be changed to the rotation speed at which the signal recorded at the target position is read. It is configured as follows.

[0007] Unlike a CD player that reproduces an audio signal, a CD-ROM player requires a high-speed reading operation of a signal. Therefore, recently, the CD-ROM player has four times, six times, eight times and eight times a specified linear velocity. 2. Description of the Related Art Disk players configured to perform a signal reading operation by rotating a disk at a high linear velocity of ten times or the like have been commercialized.

In a disk player configured to perform a reproducing operation by keeping the linear velocity constant, when the linear velocity is increased, the rotational speed on the outer peripheral side and the rotational velocity on the inner peripheral side of the disk greatly differ. Therefore, it is necessary to greatly change the rotation speed of the spindle motor for rotating the disk from low speed to high speed and vice versa.

When the search operation is performed, if the target position is on the outer peripheral side of the current position, the spindle motor is rapidly decelerated, and if it is on the inner peripheral side, the spindle motor is accelerated. It is necessary to perform the operation quickly, and if such an operation is performed frequently, a large load is applied to the spindle motor and the drive circuit, and heat is generated from the spindle motor and the drive circuit. As a result, there arises a problem that the temperature inside the disc player rises, and the control ability of an integrated circuit or the like in which a circuit for controlling the operation of the disc player is reduced.

An object of the present invention is to provide a disk player search method which solves such a problem.

[0011]

According to the present invention, when the target position is on the outer peripheral side of the current position, the search operation is performed while decelerating the spindle motor, and when the target position is on the inner peripheral side of the current position, the spindle motor is rotated. The search operation is performed while the motor is in a free-run state.

[0012]

FIG. 1 is a flowchart showing a search method according to the present invention, and FIG. 2 is a block circuit diagram of a disc player according to the present invention.

In FIG. 2, reference numeral 1 denotes a disk on which a signal is recorded at a constant linear velocity, and 2 denotes a turntable on which the disk 1 is mounted and which drives the disk 1 to rotate. It is configured to be driven. Reference numeral 4 denotes an optical pickup for reading out a signal recorded on the disk 1 by irradiating a light beam to a signal surface of the disk 1. The optical pickup 4 includes an objective lens, a photodetector, etc., and a pickup feed motor. The disk 1 is configured to be moved in the radial direction by rotation (not shown).

Reference numeral 5 denotes an RF signal amplifier circuit for amplifying an RF signal obtained from a photodetector incorporated in the optical pickup 4 and shaping the waveform, and 6 denotes a signal obtained through the RF signal amplifier circuit 5. The optical pickup 4 performs a focusing control operation for focusing a light beam of the optical pickup 4 on a signal surface of the disk 1 and a tracking control operation for causing the light beam to follow a signal track on the signal surface. The servo signal processing circuit performs a control operation of a track jump by a displacement operation of the objective lens, and the operation is configured to control the movement of the objective lens.

Reference numeral 7 denotes a digital signal processing circuit which receives a signal output from the RF signal amplifier circuit 5 and performs demodulation of various signals, and 8 denotes a digital signal processed by the digital signal processing circuit 7. Is a signal reproducing circuit to which a data signal is input, and is configured to output a data signal to the computer device 9.

A system control circuit 10 receives a signal demodulated by the digital signal processing circuit 7 and controls various operations in accordance with a switching signal output from the computer device 9. It is configured.

Numeral 11 denotes a pickup feed control circuit for controlling the radial drive of the optical pickup 4 by controlling the rotational drive operation of the pickup feed motor. The operation is controlled by the system control circuit 10. It is configured to: Reference numeral 12 denotes a spindle motor control circuit for controlling the rotation operation of the spindle motor 3, the operation of which is controlled by a motor control signal output from the system control circuit 10. Reference numeral 13 denotes a temperature detection circuit for detecting the internal temperature of the disk player, and the detection output is configured to be input to the system control circuit 10.

In such a configuration, the signal processing capability of the digital signal processing circuit 7 and the like, the signal reading capability of the optical pickup 4 and the spindle motor control circuit 12
The drive control capability of the spindle motor 3 is configured so that signal processing can be performed at, for example, 6 times and 8 times the linear velocity of a signal recorded at a constant linear velocity. I have.

In the search operation when the reading speed of the disk signal is six times or eight times higher than the specified linear speed, the search operation is performed when the target position is on the outer peripheral side of the current position. , Spindle motor 3
When the target position is on the inner peripheral side, the deceleration operation for reducing the rotation speed of the spindle motor 3 is not performed, and the acceleration operation for increasing the rotation speed of the spindle motor 3 is not performed. The type pickup 4 is moved to a target position, and the rotation speed is controlled based on a synchronization signal obtained from the disk 1 when a signal reading operation is started. And
The search operation in such a free-run state is configured to be performed when the temperature inside the disc player rises above a predetermined temperature by the temperature detection circuit 13.

The disk player according to the present invention is configured as described above, and the operation will be described next. When the disc 1 is inserted into a storage section provided in a disc player, the disc 1 is placed on the turntable 2 and a focusing control operation for focusing a light beam emitted from the optical pickup 4 on a signal surface. Is performed.

When the focusing control operation of the optical pickup 4 is performed and the focus is obtained, it is detected that the disc 1 is mounted on the turntable 2. When such a detection operation is performed, the rotation driving operation of the spindle motor 3 by the spindle motor control circuit 12 is started. Such a rotation driving operation of the spindle motor 3 is performed by detecting and utilizing a synchronization signal recorded on the disk 1. However, such operation is a well-known technique, and a description thereof will be omitted. When such an operation is being performed, a focusing control operation and a tracking control operation by the servo signal processing circuit 6 are performed, and a read operation of disk data recorded on the disk 1 is performed.

When a switching signal for performing a reproducing operation is output from the computer device 9, the system control circuit 10
With the control operation described above, the spindle motor 3 is driven to rotate so that the disk 1 has a constant linear velocity, and a signal reading operation from the disk 1 and a signal processing operation are performed.

The signal read by the optical pickup 4 is input to an RF signal amplifier circuit 5 where it is amplified and shaped, and applied to a digital signal processing circuit 7. After the signal input to the digital signal processing circuit 7 is subjected to digital signal processing, its data signal component is demodulated and input to the signal reproduction circuit 8. The data signal input to the signal reproduction circuit 8 is output to the computer device 9 through an output terminal, and the computer device 9 performs a predetermined signal processing operation.

As described above, the reading operation of the signal recorded on the disk 1 and the processing operation of the signal are performed. However, the reading operation of the signal by the computer device 9 at a linear velocity eight times as high as the prescribed linear velocity is performed. Is output, a digital signal processing circuit 7, a system control circuit 10, and a spindle motor control circuit 12
And so on, so that the signals recorded on the disk 1 can be read at eight times the speed.

As described above, the signal reading operation in this embodiment is performed. Next, the search method which is the gist of the present invention will be described with reference to the flowchart shown in FIG.

When a switching signal for reading out a desired signal from signals recorded on the disk 1 is output from the computer device 9, the system control circuit 10 enters a state in which a search operation is performed.

In the search operation, the number of tracks to the target position is calculated based on the absolute time of the current position and the absolute time of the target position, and the pickup feed control circuit 1 is calculated based on the calculated value.
The optical pickup 4 is moved to the vicinity of the target position by the rotation driving operation of the pickup feed motor 1. The moving operation accompanying the search operation of the optical pickup 4 is performed as described above.
Will be described.

When the search operation is started, it is first determined whether or not the target position is on the inner peripheral side of the current position (step A). If it is determined in step A that the target position is not on the inner peripheral side, that is, on the outer peripheral side, a control signal for decelerating the spindle motor 3 is output from the spindle motor control circuit 12, and the spindle motor 12 is decelerated. The operation is performed (step B). The rotation of the spindle motor 3 by the deceleration operation is performed so that the signal read operation at the target position is performed at a specified linear velocity or a linear multiple of a predetermined multiple of the specified linear velocity. It is configured to be controlled by the control circuit 12.

If it is determined in step A that the target position is on the inner peripheral side, the signal reading operation is performed in a high-speed use state, that is, a read operation at a linear velocity of 6 times, 8 times, or the like with respect to a specified linear velocity. It is determined whether the state is present (step C). If it is determined in step C that it is not in the high-speed use state, that is, in the use state in which the linear velocity is read at a prescribed linear velocity or about twice the prescribed linear velocity, the spindle motor control circuit 12 sends the spindle motor 3 Then, a control signal for accelerating is output, and the spindle motor 12 is accelerated (step D). The rotation of the spindle motor 3 by the acceleration operation is performed so that the signal read operation at the target position is performed at a prescribed linear velocity or a prescribed multiple of the prescribed linear velocity. It is configured to be controlled by the control circuit 12.

If it is determined in step C that the apparatus is in the high-speed use state, the drive control signal supplied to the spindle motor 3 from the spindle motor control circuit 12 is cut off, and the spindle motor 3 rotates in a state called free-run. (Step E).

The deceleration operation in step B is performed in parallel with the feed operation of the optical pickup 4. When the feed operation of the feed motor of the main body of the optical pickup 4 is completed, the signal is read out by the optical pickup 4. The operation starts. When a signal reading operation by the optical pickup 4 is performed, it is determined whether or not the optical pickup 4 is at a target position based on the position index information recorded on the disk 1 (step F).

If it is determined in step F that the position is not the target position, a track jump operation for displacing the objective lens incorporated in the optical pickup 4 is performed (step G). In the track jump operation in step G, the number of jumps decreases as approaching the target position, and one track jump is finally performed to reach the target position. If it is determined in step F that the current position is the target position, the speed control operation of the spindle motor 3 is performed based on the synchronization signal read from the disk 1 (step H).

After the deceleration operation of step B is performed, the operations of steps F, G and H described above are performed to start a desired signal reading operation. When the signal readout operation by the optical pickup 4 and the signal readout operation by the optical pickup 4 in the free-run state in step E are performed, the above-described operations in step F, step G, and step H are performed in the same manner, and the desired operation is performed. The signal reading operation is started.

In the above-described operation, the search operation in the free-run state is performed when the signal read operation is performed at a high speed. However, the temperature inside the disk player is increased by the temperature detection circuit 13 to a predetermined temperature. Even in the high state, a search operation in the free-run state can be performed.

[0035]

According to the present invention, when the search operation is performed, when the target position is on the inner side of the current position, that is, when it is necessary to perform the acceleration operation of the spindle motor, the spindle motor is kept in the free-run state. Since the moving operation of the optical pickup is performed in this manner, it is not necessary to supply a large drive current for performing the acceleration operation to the spindle motor, and the amount of heat generated from the spindle motor and the drive circuit can be suppressed.

Further, according to the present invention, the search operation in the free-run state is performed when the signal reading speed is higher than the specified speed, that is, when the signal reading operation is performed at a low speed with a small amount of heat generation. Since the search operation can be performed by a normal search operation, the search operation can be performed quickly and efficiently.

According to the present invention, the search operation in the free-run state is performed when the temperature inside the disc player is higher than a predetermined temperature, so that the amount of heat generated by the search operation can be suppressed.

As described above, according to the present invention, the amount of heat generated during the search operation can be reduced, so that the temperature inside the disc player does not rise and the operation of the disc player is controlled. The control ability of an integrated circuit or the like in which the circuit to be used is incorporated can be used to the maximum.

[Brief description of the drawings]

FIG. 1 is a flowchart showing a search method of the present invention.

FIG. 2 is a block circuit diagram of a disc player according to the present invention.

[Explanation of symbols]

 Reference Signs List 1 disc 3 spindle motor 4 optical pickup 7 digital signal processing circuit 8 signal reproduction circuit 9 computer device 10 system control circuit 11 pickup feed control circuit 12 spindle motor control circuit 13 temperature detection circuit

Claims (3)

[Claims] An optical pickup reads out a signal from a disk on which a signal is recorded at a constant linear velocity, and performs a search operation by detecting position index information recorded on the disk. In the configured disk player, when the target position is on the outer peripheral side of the current position, the search operation is performed while decelerating the spindle motor, and when the target position is on the inner peripheral side of the current position, the spindle A search method for a disc player, wherein a search operation is performed while the motor is in a free-run state. 2. A search operation in a free-run state when a target position is on the inner peripheral side of a current position when a reading speed of a signal from a disk is higher than a prescribed speed. The search method according to claim 1. 3. A search operation in a free-run state when the target position is on the inner side of the current position when the temperature inside the disk player is higher than a predetermined temperature. 2. The search method according to 1.