JPH05234287A - Track jump controlling device - Google Patents

Abstract

PURPOSE:To simplify the device configuration, to output exact speed signals so as to move a high speed head and to reduce a movement control time by using a head speed output means and a reference speed output means in a time sharing manner. CONSTITUTION:A head speed output means 1 consists of a counter, a register, and a coincidence detecting circuit FF and outputs a signal corresponding to the speed in which a pickup crosses tracks. A reference speed output means 2 consists of a counter, a register, a 0 detecting circuit, a coincidence detecting circuit and an FF and outputs a signal corresponding to a reference speed in which the pickup crosses the tracks. A control section 34 is operated by a processor and controls the means 1 and the means 2 in a time sharing manner for driving a slider motor 14 and a tracking actuator 9. The actuator 9 moves the objective lens which converges a pickup laser beam.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a track jump control device for controlling the movement of a head when jumping over a recording information reading track in a recording / reproducing device.

[0002]

2. Description of the Related Art In a recorded information reproducing apparatus, a so-called jump operation is performed in which the detected point of the recorded information is forcibly jumped from a recording track being currently traced to another target recording track. Sometimes.

In this case, in order to shorten the moving time of the head, the head is moved at a high speed, and the speed is reduced when the target track is approached. A conventional example in which the moving speed of the head is controlled in this way ("Track jump operation control device for disk player")
No. 39672) will be described with reference to FIG.

In FIG. 6, 3 is a recording medium, 4 is a head for reading recording from the recording medium 3, 5 is a differential amplifier, 6 and 10 are equalizers, 7 and 11 are switching circuits, and 9 is a diagram on the head 4. Tracking actuator for moving the objective lens that converges the laser beam to the pickup, 8 and 12 are amplifiers, 13 is an accelerating voltage generator, 14 is a slider motor that moves the head 4,
15 is a shaping circuit, 50 is a monostable multivibrator (M
MV), 51 is a low-pass filter, 52 is a differential amplifier, 5
3 is a polarity inversion circuit, 54 is a down counter, 55 is a 0 detection circuit that detects that the counter value of the counter 54 is 0, 56 is an N detection circuit that detects that the counter value is N, and 57 is a flip-flop. (FF), 58 is a switching circuit, and 59 is a power supply for outputting the voltages V ₁ and V ₂ .

In FIG. 6, three spot lights P _{1 to} P ₃ obtained by converging a laser beam onto a track of a recording medium 3 are irradiated in the illustrated positional relationship. That is, when the information detecting spot P ₂ is on the recording track, the other two spot lights P ₁ and P ₂ are located on both side edges of the track. Therefore, when the detection spot light P ₂ is deviated from the track, the difference between the light amounts of the reflected lights of the spot lights P ₁ and P ₃ changes in accordance with the deviation direction and the size thereof.

The spot lights P ₁ and P ₃ are converted into electric signals by a light receiving element in the head 4 and input to a differential amplifier 5, and the difference output signal passes through an equalizer 6, a switching circuit 7 and an amplifier 8. The tracking light is inputted to the tracking actuator 9 and the objective lens (not shown) on the head 4 is moved so that the spot light P ₁ is controlled to be at the center of the track for tracking. Further, the output of the equalizer 6 is applied to the slider motor 14 through the equalizer 10 for the slider, the switching circuit 11 and the amplifier 12, and the head 4 is controlled to be positioned at the center of the target track.

When the head jump control is instructed, the number of jump tracks from the current position to the jump destination track is set in the down counter 54 by a recording / reproducing device (not shown), and the head 4 is moved in the forward direction of the recording medium 3. The signal F / R indicating the reverse direction (rotational axis direction or outer peripheral direction) is the polarity inversion circuit 53
Is input to the differential amplifier 52 to invert the polarity of the output signal of the differential amplifier 52 to the corresponding polarity, and then the jump start command is input.

When the jump start command is input, the FF 57 is set to switch the switching circuit 7 so that the output of the polarity reversing circuit 53 is input to the amplifier 8, and the switching circuit 11 is set to the acceleration voltage generator 13 side. And the control loop for the slider motor 14 is opened. However, the output from the acceleration voltage generator 13 is 0 at this time.

The switching circuit 58 is in a reset state and is of two types.
Voltage V₁And V₂(V₁> V ₂) Output power
Voltage V from 59₁Is output by switching
It is input to 52. From the LPF 51 of the differential amplifier 52
Output is 0, the voltage V₁Is the polarity inversion time
The signal is input to the path 53, passes through the amplifier 8, and the tracking
Input to the chute 9 and move the objective lens (not shown)
Let

When the head 4 moves due to the movement of the objective lens by the tracking actuator 9, a sinusoidal signal is output to the output of the differential amplifier 5 every time the head 4 crosses a recording track, and this signal is shaped by the shaping circuit 15. The amplitude is sliced and shaped into a rectangular pulse wave.

The MMV 50 is output from the shaping circuit 15.
A certain time T from the rising edge of the pulse ₁Only the amplitude A
Output the loose. Therefore, the output of the LPF 51 is
Let T be the time until the head 4 crosses the next track.
And AT₁The average voltage of / T is output. That is,
AT₁Is constant, and if the moving speed of the head 4 increases,
T becomes smaller, AT₁/ T is proportional to the moving speed of the head
It becomes the voltage.

In the differential amplifier 52, the AT from the LPF 51
_The voltage of ₁ / T and the voltage of V ₁ from the switching circuit 58 are subtracted and output. The voltage of this difference is input to the polarity reversing circuit 53, the switching circuit 7 and the amplifier 8 to accelerate the movement of the objective lens by the tracking actuator 9. As a result, the moving speed of the read beam increases and the LP
The output value AT ₁ / T from F51 rises and the objective lens is accelerated until AT ₁ / T becomes equal to V ₁ . AT ₁
When / T = V ₁ , the objective lens moves at a constant speed and the read beam moves at a constant speed.

On the other hand, the pulse output from the MMV 50 is input to the down counter 54, and the recorded value is subtracted every time the pulse is output from the MMV 50 from the jumping track number input at the start of jumping. When the reading beam approaches the target recording track, it is necessary to reduce the moving speed of the objective lens and stop it at the target track. Therefore, the N detection circuit 56 detects that the target track is N tracks. That is, the down counter 54
It is detected that the count value of N has become N, and the switching circuit 58
To output the output voltage V ₂ from the power supply 59.

When the voltage V ₂ is output from the switching circuit 58 and input to the differential amplifier 52, the moving speed of the head 4 is reduced by the above-mentioned operation. Further, the objective lens moves at a reduced speed and the down counter 54 has a count value of 0, that is, the 0 detection circuit 55 knows that the target track has been reached. The FF 57 is reset and the switching circuit 7 is operated to operate the equalizer. The output from 6 is input to the amplifier 8.
When the output from the equalizer 6 is input to the amplifier 8, the normal tracking control is started and the objective lens is controlled to be located at the center of the target track.

After that, a processor (not shown) instructs the acceleration voltage generator 13 to generate an acceleration voltage, and the slider motor 14 is rotated. By the rotation of the slider motor 14, control is performed so that the head 4 is located at the center of the target track.

[0016]

As described above, in the conventional track jump control device, the generation of the control signal for the tracking actuator and the slider motor is constituted by separate circuits. This complicates the device configuration.

Further, a signal which gives a reference for the speed of moving the objective lens is obtained by switching from a power source which outputs two kinds of voltages. For this reason, the circuit configuration becomes complicated and it is difficult to form an IC. SUMMARY OF THE INVENTION It is an object of the present invention to provide a track jump control device which simplifies the device configuration and outputs an accurate speed control signal to move the head at high speed to shorten the movement control time.

[0018]

Means adopted by the present invention for solving the above-mentioned problems will be described. In a track jump control device for a disc player, which comprises a tracking actuator for moving an information detection point of a pickup for reading information from a recording medium and a slider motor for moving the head, (a) the pickup crosses a track. Head speed output means for outputting a signal corresponding to the speed, (b) reference speed output means for outputting a signal corresponding to the reference speed at which the pickup crosses the track, and (c) an output signal from the head speed output means. Difference signal output means for outputting a difference signal of the output signals from the reference speed output means, and (d) the head speed output means and the reference speed output means for driving the slider motor and the tracking actuator. And a control unit that controls in time division.

[0019]

From the head speed output means, the pickup outputs a signal corresponding to the speed across the track. The reference speed output means outputs a signal corresponding to the reference speed at which the pickup crosses the track.

From the difference signal output means, a signal of the difference between the output signal from the head speed output means and the output signal from the reference speed output means is output and input to the slider motor and the tracking actuator. The control section controls the head speed output means and the reference speed output means in a time-division manner during the slider motor control and the tracking actuator control.

As described above, since the head speed output means and the reference speed output means are used in a time division manner, the speed servo circuit can be shared and the circuit structure can be simplified, and the slider motor and the tracking actuator can be used. Can be operated at an optimum moving speed, and the movement control time can be shortened.

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a block diagram of an embodiment of the present invention, in which a recording medium 3, a head 4, a differential amplifier 5, equalizers 6 and 10, switching circuits 7 and 11, amplifiers 8 and 12, L
The PF 16, the tracking actuator 9, the slider motor 14, and the shaping circuit 15 are as described in FIG. 6, and the tracking operation of the normal head 4 is as described in the conventional example.

Reference numeral 1 is a head speed output means and 2 is a reference speed output means, which will be described later in detail with reference to FIGS. 30 is a differential amplifier, 31 is a polarity inverting circuit,
Reference numeral 32 is a low-pass filter, 33 is a counter, and 34 is a control unit.

The head speed output means 1 comprises a counter 41, a register 42, a match detection circuit 43 and a flip-flop (FF) 44, as shown in the embodiment of FIG. Further, the reference speed output means 2 has a counter 21, a register 22, and a 0 detection circuit 2 as shown in the embodiment of FIG.
3. Match detection circuit 24 and flip-flop (FF)
25.

First, the operation of the head speed output means 1 will be described with reference to FIG. The register 42 includes a control unit 34.
Thus, the data for determining the output pulse width corresponding to the head speed signal is input and stored. The counter 41 is reset at the rising edge of a pulse from the shaping circuit 15 indicating the time when the head 4 crosses the track, and counts the clock pulse input from the control unit 34.

The matching circuit 43 outputs a pulse when the count value of the counter 41 and the data value stored in the register 42 match. The FF 44 sets the output to 1 at the same time when the counter 41 is reset, and sets the output to 0 when the pulse is output from the coincidence circuit 43. Therefore, FF4
The width of the output pulse from 4 can be changed by changing the data value stored in the register 42.

Next, the operation of the reference speed output means 2 will be described with reference to FIG. The register 22 includes a control unit 34.
Thus, the data for determining the output pulse width corresponding to the reference speed of the head is input and stored. The counter 21 counts clock pulses from the control unit 34. Counter 21
If the flip-flop is composed of M stages, for example, the operation of returning to 0 and counting every 2 ^M clock pulses from the control unit 34 is repeated.

The 0 detection circuit 23 outputs a pulse when the count value of the counter 21 becomes 0. The coincidence detection circuit 24 outputs a pulse when the count value of the counter 21 and the data value stored in the register 22 become equal. FF2
In reference numeral 5, the output is set to 1 from the time when the pulse is output from the 0 detection circuit 23 to the time when the pulse is output from the coincidence detection circuit 24. Therefore, the width of the output pulse from the FF 25 can be changed by changing the data value stored in the register 22.

Next, the operation of the embodiment will be described with reference to the operation flowchart of FIG. A jump command is input to the control unit 34 from a recording information reproducing device (not shown) to start the operation. At this time, an F / R signal indicating the number of jumping heads (N _J ) and the head movement in the forward direction or the backward direction is transferred from the recording information reproducing apparatus and stored in a register (not shown). Further, the control unit 34 is processed by a processor (not shown).

For ease of explanation, it is assumed that the counter 21 of the reference speed output means counts 0 to 99 and repeats it, and the register 22 stores the data value N for both high speed and low speed.
It is assumed that _R = 20, and that the register 12 of the head speed detecting means stores N _SH = 20 at high speed and N _SL = 60 at low speed.

Process S1 In process S1, it is determined whether or not the number N _{J of} jumping heads is larger than N _J1. If NO, the process proceeds to process S6, and if YES, the process proceeds to process S2. That is, in step S1, it is determined whether or not the head needs to be significantly moved, and if it is necessary, the coarse adjustment control by the slider motor 14 is performed, and if not, only the fine adjustment control by the tracking actuator 9 is performed. It is determined whether or not to make.

Process S2 In process S2, the coarse adjustment control is first started, and when the jump command is input, the switching circuit 11 is switched to switch the input to the amplifier 12 from the output of the equalizer 10 to the output of the LPF 13. Further, the polarity inversion circuit 31 is switched to the polarity based on the F / R stored in the register (not shown).
The register 22 of the reference speed output means 2 stores a data value N _R =
20 is sent and stored, and the data value N _SH = 20 during high speed movement is sent and stored in the register 42 of the head speed output means 1. Further, the counter 33 is reset to start counting.

When the above-mentioned data value is set and the operation is started, the head speed output means 1 and the reference speed output means 2 output a pulse by the above-mentioned operation.
These pulses are subtracted by the differential amplifier 30 and input to the slider motor 14 through the polarity reversing circuit 31, LPFs 32 and 13, the switching circuit 11 and the amplifier 12, and the head 4 is moved.

The moving speed of the head 4 is such that the output value from the LPF 32 becomes zero. That is, the counter 21 of the reference speed output means 2 is repeated with 100 clock pulses, and the FF 25 outputs a pulse of 20 (= N _R ) clock pulse width, while the head speed output means 1
20 (= N _SH ) every time the head 4 crosses the track
Since the pulse of the clock pulse width is output, the head 4
The speed control is performed so that the time when the track crosses the track becomes equal to the counting time of 100 clock pulses.

Process S3 In process S3, it is determined whether the counter value counting the output pulses from the head speed output means 1 is X ₁ or not. If NO, it is determined whether the counter value is X ₁ or not. If so, the process proceeds to step S3.

The counter value is X₁Is the head
Is the target track N for coarse adjustment control _J1Approaching,
Switch the moving speed from high to low and stop at the coarse adjustment target head.
It is for stopping, for example, 1 of the coarse adjustment target head.
Coarse adjustment target track when switching to low speed before 0 track
Number N_J110 less than X₁It becomes the value of.

Process S4 If the determination result in process S3 is YES, the control unit 34 outputs the data value N _SL = 60 to the register 42 of the head speed output means 1 and stores it. 60 in register 42
Is set, the head is decelerated so that the average voltages output from the head speed output means 1 and the reference speed output means 2 become equal. That is, since the average voltage from the reference speed output means 2 is 20/100, the average voltage from the head speed output means 1 is 6 if the time for the head to cross the track is equal to the time for counting 300 clock pulses.
It becomes 0/300 and becomes equal. That is, in the case of low speed movement with respect to high speed movement, the movement is decelerated to one third.

Process S5 In process S5, it is determined whether or not the count value of the counter 33 is equal to the target track number N _J1 of the rough adjustment control. If it is N0, it is determined whether the counter value is N _J1 or not. The determination is continued, and if YES, the process proceeds to step S6.

Processing S6 From processing S6, the fine adjustment control by the tracking actuator 9 is started, and the switching circuit 7 is switched to switch the input to the amplifier 8 from the EQL6 to the output of the LPF32. Further, the data value N _SH = 20 at the time of high speed movement is sent and stored in the register 42 of the head speed output means 1.

When the data is stored in the register 42, a signal for high speed control is output to the output of the LPF 32, is input to the tracking actuator 9 through the amplifier 8 and is input to the tracking actuator 9 through the amplifier 8 as described in step S2. Move at high speed. Process S7 In process S7, it is determined whether or not the count value of the counter 33 is X ₂ , and if NO, the determination whether or not the count value is X ₂ is continued, and if YES, the process proceeds to process S8. Move.

That is, in step S7, the time when the high-speed operation of the tracking actuator is switched to the low-speed operation is detected, and the value of X ₂ is specified to be, for example, 5 less than the target jumping track number N _J. It Process S8 Data value N _SL = 6 from control unit 34 to register 42
0 is output and stored.

When the data is stored in the register 42, a signal for low speed control is output to the output of the LPF 32, is input to the tracking actuator 9 through the amplifier 8 and is input to the tracking actuator 9 through the objective lens (not shown) as described in step S4. Move at low speed. In step S9, it is determined whether or not the count value of the counter 33 is equal to the number N _J of jumping tracks, and if NO, the process continues as it is.
In the case of YES, the process proceeds to step S10.

Process S10 Since the movement of the head comes on the target track, the control unit 34
Then, a switching command is issued to the switching circuits 7 and 11, and the process is terminated. When the switching circuits 7 and 11 are switched, normal tracking control is performed.

In the above description of the embodiment, the same data value was stored in the register 22 of the reference speed output means 2 for both high speed and low speed movement, but speed control is performed by changing the data value at high speed and low speed. It can also be done. Further, in the embodiment, the speed control of two stages of high speed and low speed is performed, but the data value to the register can be changed a plurality of times to perform the multi-stage speed control.

Further, as shown in FIG. 5, a frequency dividing circuit 45 for frequency-dividing the clock pulse from the control unit by N _T and a frequency dividing circuit 46 for frequency-dividing N _S are provided, and their outputs are switched by a switching circuit 47.
It is also possible to change the pulse width of the head speed signal output from the head speed output means by switching with and inputting to the counter 41.

Although one embodiment of the present invention has been described above, the present invention is not limited to this embodiment, and various modifications can be made according to the gist of the invention.

[0047]

As described above, according to the present invention, the following effects can be obtained. (A) Since the head speed output means and the reference speed output means are used in a time division manner, the slider motor and the tracking actuator can be operated at the optimum moving speed, and the movement control time can be shortened.

(B) The head moving speed signal and the reference speed signal are so arranged that the common clock pulse is counted and a pulse having a time output value equal to the numerical value stored in the register is set to 1. The device configuration can be greatly simplified, a circuit configuration suitable for integration into an IC can be obtained, and an accurate signal value can be output.

(C) By changing the value set in the register, an accurate signal value can be output even at low speed.

[Brief description of drawings]

FIG. 1 is a configuration diagram of an embodiment of the present invention.

FIG. 2 is an embodiment of the head speed output means of the embodiment.

FIG. 3 is an embodiment of a reference speed output means of the same embodiment.

FIG. 4 is an operation flowchart of the embodiment.

FIG. 5 is another embodiment of the head speed output means.

FIG. 6 is a configuration diagram of a conventional example.

[Explanation of symbols]

 1 Head Speed Output Means 2 Reference Speed Output Means 3 Recording Medium 4 Heads 5, 30, 52 Differential Amplifiers 6, 10 Equalizers 7, 11, 58 Switching Circuits 8, 12 Amplifiers 9 Tracking Actuators 13 Accelerating Voltage Generators 14 Slider Motors 15 Shaping circuit 16,32,51 Low-pass filter 21,33,41 Counter 22,42 Register 23,550 Detection circuit 24,43 Match detection circuit 25,44,57 Flip-flop 31,53 Polarity inversion circuit 34 Control unit 45,46 Dividing circuit 50 Monostable multivibrator 54 Down counter 56 N value detection circuit 59 Power supply

[Procedure amendment]

[Submission date] February 1, 1993

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] 0032

[Correction method] Change

[Correction content]

Process S2 In process S2, the coarse adjustment control is first started, and when the jump command is input, the switching circuit 11 is switched by N / S switching.
The input to the amplifier 12 from the output of the equalizer 10 to L
Switching to the output of PF16 and amplification by switching circuit 7
Switch the input to the device 8 to the ground not shown
It Further, the polarity inverting circuit 31 is switched to the polarity based on the F / R stored in the register (not shown). A data value N _R = 20 is stored in the register 22 of the reference speed output means 2.
Is sent and stored in the register 4 of the head speed output means 1.
In 2, the data value N _SH = 20 when moving at high speed is sent out and stored. Further, the counter 33 is reset to start counting.

[Procedure Amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0033

[Correction method] Change

[Correction content]

When the above-mentioned data value is set and the operation is started, the head speed output means 1 and the reference speed output means 2 output a pulse by the above-mentioned operation.
These pulses are subtracted by the differential amplifier 30 and input to the slider motor 14 through the polarity reversing circuit 31, LPFs 32 and 16 , the switching circuit 11 and the amplifier 12 to move the head 4.

[Procedure 3]

[Document name to be amended] Statement

[Correction target item name] 0039

[Correction method] Change

[Correction content]

Process S6 The fine adjustment control by the tracking actuator 9 is started from the process S6, and the switching circuit 7 is switched by N / S switching.
Therefore, the input to the amplifier 8 is switched to the output of the LPF 32,
Also, the input to the amplifier 12 by the switching circuit 11 is shown in the figure.
Switch to the ground you have not done. Further, the data value N _SH = 2 at the time of high speed movement is stored in the register 42 of the head speed output means 1.
Send 0 and store.

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0043

[Correction method] Change

[Correction content]

Process S10 Since the movement of the head comes on the target track, the control unit 34
The switching command is issued to the switching circuits 7 and 11 by the N / S switching from (1) to ( 5) and the processing is terminated. When the switching circuits 7 and 11 are switched, normal tracking control is performed.

[Procedure Amendment 5]

[Document name to be amended] Statement

[Correction target item name] 0048

[Correction method] Change

[Correction content]

(B) For the head moving speed signal and the reference speed signal, common clock pulses are counted, and the output value is logic- valued with a time width equal to the numerical value stored in the register.
Since the pulse for setting to 1 is sent, the device configuration can be greatly simplified, a circuit configuration suitable for IC implementation can be obtained, and an accurate signal value can be output. ─────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] February 1, 1993

[Procedure Amendment 1]

[Document name to be corrected] Drawing

[Name of item to be corrected] Fig. 4

[Correction method] Change

[Correction content]

[Figure 4]

Claims (3)

[Claims] 1. A track jump control device for a disc player, comprising: a tracking actuator for moving an information detection point of a pickup on a head for reading information from a recording medium; and a slider motor for moving the head. Head speed output means for outputting a signal corresponding to the speed at which the pickup crosses the track; (b) reference speed output means for outputting a signal corresponding to the reference speed for the pickup to cross the track; and (c) the head speed output means. Difference signal output means for outputting a difference signal between the output signal from the slider and the reference speed output means, and (d) the head speed output means and the reference speed output means to the slider motor and the tracking actuator. And a control unit that controls the drive of Track jump control device for the butterflies. 2. A numerical value in which the head speed output means is composed of a register and a counter, causes the counter to count clock pulses, and the count value of the counter is stored in the register from the time when the pickup crosses a track. 2. The track jump control device according to claim 1, wherein the track jump control device is configured by a gate circuit that outputs a pulse until a time point equal to. 3. The reference speed output means comprises a register and a counter, causes the counter to count clock pulses, and changes the count value of the counter to a numerical value stored in the register from the time when the count value reaches a certain count value. 3. The track jump control device according to claim 1, wherein the track jump control device is configured by a gate circuit that outputs a pulse until they become equal to each other.