JPH01107326A - One track jump automatic adjusting device - Google Patents

Abstract

PURPOSE:To eliminate the need of a manual adjustment by controlling a jump acceleration automatic adjusting part based on a result decided whether the state of plural one track jumps is good or bad by a level comparator. CONSTITUTION:A track motor 11 jumping and moving an objective lens to the direction of an adjacent track is provided and a one track jump driving system 12 having the jump acceleration automatic adjusting part 17 of one track jump by the track motor 11 and driving the track motor 11 is provided. Then, the adjusting part 17 of the jump driving system 12 is controlled based on the decided result of the level comparator 19 which decides whether the state of the plural one track jumps executed by the driving system 12 is good or bad. Thus, the adjustment on a production line by a worker is made to be unnecessary.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to a one-track jump automatic adjustment device in an optical disk drive or magneto-optical disk drive.

BACKGROUND ART Conventionally, as a control method for this type of one-track jump drive circuit, there is a method using an interloop type bang-bang control as shown in FIG.

That is, a track motor l for one-track jump drive is connected to the midpoint of a pair of drive transistors Q, Q, connected between a +Vpfi source and a -Vp power source. These driving transistors Q, , Q□ are
Switch SW by PU2.

Under the alternate on/off control of SW2, the input applied voltage VrN is supplied from the constant voltage source 3 via the voltage dividing resistors R and VR.
(V) is input directly to the OP amplifier 4 when the switch SW is on, and to the OP amplifier 4 via the inverter 5 whose polarity is inverted by "-1" when the switch SW is on. Drive transistor Q through
,,Q,.

Here, F (N); Force M applied to the track motor
[kg); Moving part mass kFr (N/A); Truck motor thrust constant PA
(A/V); Power amplifier gain α [m/s! ] ;
Jump acceleration VtN (V); Input applied voltage (variable) B
;Assuming the gain of the op amp, F=M・α VXN-B-PA-kFT ゞPa°8°PA″1・・・・・・・・・・・・・(1)
becomes. Also, the moving distance x Cm) is (however, X is a minute displacement), X=-αt...
(2) becomes. Therefore, if the moving time T (s) is constant as shown in FIG. 12, the moving jump distance X is proportional to the jump acceleration α from equation (2). That is, XOC
α ・・・・・・・・・(
3) The moving distance X referred to here is two times the track pitch of the optical disc, and is a constant value. Therefore, the jump acceleration α must also be kept constant.

However, in reality, the voltage variation of the constant voltage source 3, O
Variations in resistance around P amplifier 4, variations in gain of power amplifier 6, variations in track motor thrust constant,
The jump acceleration differs from disk drive to disk drive due to the sum total of variations in the mass of the moving parts. As a result, the jump movement distance X varies, the stability after the jump becomes poor, and in the worst case, tracking becomes impossible or tracking ends up on a different track.

For this reason, on the production line of optical disk drives, each unit is made to jump one track, and while observing the track error signal at that time (see Figure 12 (C)) with an oscilloscope, the variable resistor VR is It is necessary to adjust the input applied voltage VIN to absorb the various variations mentioned above.

That is, the operator must operate and adjust the variable resistor for each unit on the production line, which is cumbersome and not suitable for mass production, and it is also easy for the operator's observational subjectivity to be involved.

Furthermore, such problems occur not only on the production line, but also when, for example, the circuit board is replaced when repairing a fault in a disk drive on the market, it is necessary to bring the disk drive back to the production line and perform the above-mentioned adjustment work. It is something that must be done.

Purpose The present invention has been made in view of the above points, and provides a track jump automatic adjustment device that eliminates the need for manual adjustment by an operator such as operating a variable resistor, and can automatically achieve the optimum input applied voltage state. The purpose is to.

Structure In order to achieve the above object, the present invention executes one-track jump multiple times and observes the dispersion distribution of the jump state, thereby automatically knowing how to adjust the one-track jump and adjusting the one-track jump accordingly. The jump drive system is automatically adjusted, and information is optically recorded or reproduced by irradiating a light beam through an objective lens onto an optical information recording medium that has tracks formed in a concentric or spiral shape. The optical information recording and reproducing apparatus is provided with a track motor that jump-moves the objective lens in the direction of an adjacent track, and is equipped with an automatic jump acceleration adjustment section for one track by the track motor to drive the one-track jump. Set up a drive system,
A level comparator is provided to determine the quality of multiple one-track jumps performed by this one-track jump drive system, and based on the determination result of this level comparator, the above]
The present invention is characterized in that a control means for controlling the jump acceleration automatic adjustment section of the track jump drive system is provided.

A first embodiment of the present invention will now be described with reference to FIGS. 1 to 6. This embodiment is applied to a system in which the energization time width T is constant and the input applied voltage VIN is variable, as in the case of FIG. 11. First, a track motor 11 is provided which jump-moves an optical pickup including an objective lens (not shown) etc. in the direction of an adjacent track. A one-track jump drive system 12 is provided for this track motor 11. This 1-track jump drive system 12 inputs the manually applied voltage VTN to the OP amplifier 13 via the switch SW1 as +VIN, or inputs it as -VrN via the inverter 14 and switch SW2 of "-1", and gains is +■p via the power amplifier 15 which is PA.

-Drive transistors Q l lQ each connected to -Vp
The track motor 11 is configured to be driven by one track by inputting the signal to the signal 2 and turning it on alternately. Here, the switch SW.

SW2 is a control unit 7iJ from CPU16 as a control means.
It is controlled to be turned on and off alternately at the time of one track jump by a signal, and its time width T is constant. Here, the one-track jump drive system 12 is provided with a D/A converter 17 as a variable voltage source for jump acceleration adjustment, which serves as a jump acceleration automatic adjustment section, and its output VD
A(V:l is input to an adder 18 together with a constant voltage +V old N, and the adder 18 is configured to output an input applied voltage VIN.The D/A converter 17
is to regulate the voltage variable adjustment range, and now, as shown in Figure 2, the voltage variable adjustment range is ±D C with respect to the reference value.
If only V) is required, the output voltage VpA of this D/A converter 17 is initially set to vDA=D [■]. Then, the output VDA from this D/A converter 17
The O value is automatically variably adjusted by the CPU 16 through processing described later.

On the other hand, in the optical disk device of this embodiment, the track error signal Trε can be detected by a well-known detection mechanism, and a level comparator 19 is provided which receives the track error signal Trε as an input. This level comparator 19 has positive and negative reference voltages +REF+V REF
It consists of two comparators 20 and 21 for comparing with. An up/down counter 23 is connected to this level comparator 19 via a count controller 22. Here, the counter controller 22 includes a NAND gate 24 and outputs one of three types of outputs ■■■ to the counter 23 according to the signal from the level comparator 19. Further, the up/down counter 23 is C
It is controlled by the PU 16 to perform a counting operation at a predetermined timing, specifically at the rising edge of the deceleration pulse, and outputs a counter output to the CPU 16 for control.

Here, the level of the output ■■■ of the counter controller 22, its state, and the operation of the counter are as follows. That is, the output ■■ instructs the counter 23 to either up or down, and the output ■ becomes an enable signal.

Under the configuration of 2, the automatic adjustment according to this embodiment is automatically performed according to the flowchart (algorithm) shown in FIG. 7 when the power of the disk drive device is turned on. Prior to this, since the input applied voltage VIN of this embodiment has a variable width of ±D, as shown in FIG. 2, VIN=VmrNNVi+tN+2D. On the other hand, as described above, VDA=D is set as the initial setting of the D/A converter 17.

That is, the reference value VIN=VoldN+D.

Then, ■track jump is executed.

At this time, the generated track error signal Trε is input to the level comparator 19. Then, the level comparator 19, specifically the comparators 20 and 21, determines whether the jump condition is good or not, that is, whether the jump acceleration is large, small, or optimal.

A signal from the level comparator 19 based on such a determination result is outputted to the counter control 22 to generate a control signal for the up/down counter 23, and the counter 23 is operated in accordance with the control signal.

For example, when the track error signal Trε shown in FIG. 4(b) is obtained, each output from the counter controller 22 becomes as shown in FIG. 4(c), which means the judgment result is the optimum state. However, the counter 23 enters a no-count state. Furthermore, when the track error signal Trε as shown in FIG. 5(b) is obtained, each output from the counter controller 22 becomes as shown in FIG. means the result, counter 23
is in an up-count state. On the other hand, when the track error signal Trε as shown in FIG. 6(b) is obtained, each output from the counter controller 22 is
), which means a large (excessive) determination result, and the counter 23 enters a down-counting state.

As shown in the flowchart of FIG. 7, such operations are repeated a set number of times.

When the set number of one-track jump tests are completed,
The count value of the up/down counter 3 is output to the CPU 16. If the read result is within a certain range, the input applied voltage VIN is optimal, and if it is higher than that, the input applied voltage V
If IN is too high or below, the CPU 16 determines that the input applied voltage vrN is too low. That is, if it is not optimal, the value of the D/A converter 17 is varied from the initial setting value according to such a measurement distribution. When it is determined that the input applied voltage VIN is excessive, the D/A converter 1
Control is performed to lower the output VDA of the D/A converter 17, and to raise the output VDA of the D/A converter 17 when it is determined that the input applied voltage VIN is too low. The measurement distribution obtained by the one-track jump test obtained in this way is, for example, shown in Figure 3 (
The results are as shown in a) to (c).

Then, as described above, the jump test, distribution measurement, etc. are repeated until the optimum distribution is determined.

Now, the number of track jump jump tests is 10.
times, a 4-bit binary counter is used as the up/down counter 23, and it is assumed that the output of this counter 23 is O±4 counts, which is considered optimal.
In the case of insufficient movement, the following measurement results (distribution) will be obtained.

For example, if the counter's no-count operation is indicated by -, up-count operation by ↑, and down-count operation by ↓, then the 10th counter output = measurement result is 2, so the input It is determined that the applied voltage VIN is optimal as it is. Also, if
The tenth counter output=measurement result is 8, and based on the state distribution, it is determined that the input applied voltage VIN is greatly excessive. Furthermore, in the case where the following occurs, the 10th counter output=measurement result is 1o, so it is determined that the input applied voltage VIN is in a state of insufficient movement.

In addition, according to this embodiment, when the power is turned on, a jump test of one track jump is performed multiple times, the quality distribution of the one track jump state is determined, and the value of the D/A converter 17 is automatically determined based on the result. variably controlled,
Since the input applied voltage VIN and therefore the jump acceleration α are adjusted, automatic processing can be performed without placing any burden on the operator. From a production line perspective, it does not require adjustments on the production line, making it suitable for mass production, and also creates compatibility between disk drive boards, eliminating the need for adjustments after board replacement.

Next, a second embodiment of the present invention will be described with reference to FIG. In this embodiment, the up/down counter 23 is omitted, and the output signal from the count controller 22 is input directly to the CPtJ16 every track jump, and the CPU 1
This is used for reading judgment in step 6.

Further, the counter controller 22 may also be omitted and the output from the level comparator 19 may be directly read by the CPU 16.

Furthermore, a third embodiment of the present invention will be explained with reference to FIG.

In the embodiment described above, the time width T=constant, the input applied voltage VtN
This is an example of application to a variable method, but this embodiment is applied to a method in which the input applied voltage VIN is constant and the time width T is variable. Therefore, the D/A converter 17 is omitted and the VIN = A constant voltage source 25 is provided6
In addition, in the 1-track jump drive system 12, the switch sw,
, sw4 is a jump acceleration automatic adjustment section, and CPU1
6 management, the on-time width T of these switches sw, , sw is appropriately varied.

The one-track jump automatic adjustment force formula of this embodiment can also be applied to a method of detecting the zero-crossing point of the track error signal Trε and generating a deceleration pulse, as shown in FIG. 10, for example. In Figure 10, acceleration pulse width T1
is the output until the track error signal Trε crosses zero and is variable, whereas the deceleration pulse width T! after the zero cross is variable. is constant.

Effects Since the present invention is configured as described above, the one-track jump acceleration is automatically controlled to be constant, thereby eliminating the need for adjustment by operators on the production line, and making it suitable for mass production. In addition, it is possible to make the substrates compatible with each device.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing a first embodiment of the present invention, and FIG.
The figure is a waveform diagram of variable human power applied voltage, Figure 3 is a state distribution diagram of various one-track jumps, Figure 4 is a diagram of various signal waveforms at the optimum time, Figure 5 is a diagram of various signal waveforms at overshooting, and Figure 6 is a diagram of various signal waveforms when overshooting. 7 is a flowchart, FIG. 8 is a block diagram showing a second embodiment of the present invention, and FIG. 9 is a block diagram showing a third embodiment of the present invention. 10th
11 is a waveform diagram showing a modified example, FIG. 11 is a block diagram showing a conventional example, and FIG. 12 is an operation waveform diagram thereof. 11... Track motor, 12... 1 track jump drive system, 16... CPU <control means), 17.
・・D/A converter (jump acceleration automatic adjustment section),
19...Level comparator, sw, sw4...Switch (jump acceleration automatic adjustment section)

Claims (1)

[Claims] In an optical information recording/reproducing apparatus that optically records or reproduces information by irradiating a light beam through an objective lens onto an optical information recording medium having tracks formed in a concentric or spiral shape, the objective lens is connected to an adjacent track. A track motor for jumping in the direction is provided, a one-track jump drive system is provided that includes an automatic jump acceleration adjustment section for one track by the track motor, and drives the track motor, and the one-track jump drive system executes the jump movement. A level comparator is provided for determining the quality of a plurality of one-track jump states, and a control means is provided for controlling the jump acceleration automatic adjustment section of the one-track jump drive system based on the determination result of the level comparator. Features 1 track jump automatic adjustment device.