KR0129242B1 - Optical pick us system - Google Patents

Abstract

An apparatus for preventing vibration of actuator in optical disk system having electromagnets mounted in regions opposed to a actuator coil to prevent the vibration of pick up; a switch control signal generated controlling the ON/OFF of the switch according to regeneration mode in feeding the pick up; and a voltage-current convertor converting to the current proportional to the voltage applied through the switch control signal generator to supply it to the electromagnets through a current amplifier is disclosed. Thereby, it is possible to reduce access time and to enhance performance.

Description

Actuator anti-vibration device of optical disc system

1 is a pickup configuration of a Sony product in a conventional optical disc system.

2 is a pickup configuration of a Sanyo product in a conventional optical disc system.

3 is a counter electromotive voltage waveform due to actuator vibration in FIGS. 1 and 2;

4 is a block diagram of an actuator vibration preventing device of the optical disk system of the present invention.

5 is an output waveform diagram of each part according to FIG.

6 is a magnetic field generated by permanent magnets and electromagnets in FIG.

* Explanation of symbols for main parts of the drawings

1 Lens 2 Actuator Coil

3: permanent magnet 4: actuator module

5: pickup 6: gear

7: transfer mechanism 8: vibration damper

9: electromagnet 10: switch control signal generator

11 voltage-current converter 12 current amplifier

M: Feed mechanism motor SW1: On / off switch

The present invention is to prevent the vibration of the actuator inside the pick-up (Pick Up) to read the data in the magneto-optical disk in the optical disk system, in particular the electromagnet attached to the actuator symmetrically when the current flows in the electromagnet permanent magnet direction The present invention relates to an actuator vibration preventing device of an optical disc system, which is configured to hold an actuator so as to be pushed out with an N pole to prevent vibration.

The pickup structure of the conventional optical disc system, as shown in Figs. 1 and 2, is a permanent magnet (3) when a current flows through the actuator coil (2) in a module together with the lens (1) In response to the actuator module 4 to move up, down, left and right, and a transfer mechanism for transferring the pickup 5 by changing the linear reciprocating motion by the rotation of the gear 6 ( 7) and a vibration damping damper 8 attached to the pickup 5 to reduce vibration generated when the transfer mechanism 7 is stopped.

Looking at the conventional technology configured as described above are as follows.

When current flows to the actuator coil 2 which is the actuator module 4 together with the lens 1, the actuator module 4 reacts with the permanent magnet 3 on the outside of the actuator coil 2. It moves to the bottom, left and right.

In this case, the actuator module 4 moves up and down when performing a focus search and a focus servo, and the actuator module 4 moves left and right as a track search. ) And tracking servo.

The left and right movement of the actuator module 4 is usually guaranteed to ± 0.5 to 1 mm, but in order to maintain a stable state, the actuator module 4 is moved to ± 0.5 to 80 µm.

If the moving mechanism 7 is moved by 80 m or more using only the actuator module 4, the restoring force of the actuator module 4 becomes larger, and the tracking servo becomes unstable even with a small external shock.

On the other hand, if it is necessary to move thousands of tracks to obtain data from the disc, due to the limitation of the actuator, the pickup 15 is moved to the vicinity of the special rack with the desired data by using the transfer mechanism (7). Find.

In particular, when the access (access) at high speed, the transfer mechanism (7) must be moved quickly, the actuator module (4) is vibrated by inertia when the transfer mechanism is stopped. Figure 3 shows the counter electromotive voltage caused by the actuator module vibration after the transfer mechanism 7 stops, and knowing how much the amplitude of the counter electromotive force vibrates, and in severe cases reaches several hundred μm.

However, as described above, conventionally, vibration occurs when the transfer mechanism moves and stops at high speed access, and this vibration appears larger when the transfer mechanism is made faster to reduce the access time. In this case, there is a problem that the access time may be longer. This is because the time until the actuator vibration is alleviated is included.

Accordingly, an object of the present invention for solving the conventional problems as described above is to provide an actuator vibration preventing device of the optical disk system to eliminate the vibration of the actuator generated when the transfer mechanism is stopped after moving at high speed access.

Accordingly, another object of the present invention is to provide an actuator anti-vibration apparatus of an optical disc system that can reduce access time by eliminating vibration of an actuator.

Still another object of the present invention is to prevent actuator vibration of an optical disc system in which data can be read from a disc in a servo state in a faster time by preventing the vibration by fixing the actuator in the pickup after the transfer mechanism stops during access. It is for providing a device.

Still another object of the present invention is to attach an electromagnet to the pickup to hold the actuator to prevent vibration, and to provide a switch control signal generation circuit for turning on / off the electromagnet to hold the actuator at the most severe time of actuator vibration. It is to provide an actuator anti-vibration device of an optical disc system.

The actuator vibration preventing device of the optical disk system of the present invention for achieving the above object is, as shown in FIG. 4, the permanent magnet when the current flows to the actuator coil (2) in a module together with the lens (1) Reaction (3) and the pickup (5) to move the actuator module (4) up, down, left, right, and the upper and lower of the actuator coil (2) in the pickup (5) when the current flows the actuator The electromagnet 9 which prevents the module 4 from vibrating, and the switch control signal generation part 10 which generate | occur | produces a switch control signal so that ON / OFF switch SW1 may be turned on or off are comprised.

Referring to the operation and effects of the present invention configured as described above in detail.

The pickup 5 moves very slowly when the current state is a normal state, that is, the actuator module 4 reads data while following the tracks in the disc as the disc rotates.

Therefore, the transfer mechanism motor M for moving the pickup 5 is subjected to a low voltage such as V ^{± 2} as shown in FIG. 5A.

At this time, the switch control signal generator 10 generates an off signal to the on / off switch SW1 so that the switch operating terminal is switched to ②.

Then, since no current is supplied to the electromagnet 9 existing in the pickup 5, the electromagnet 4 is not magnetic and has no influence.

In this state, when a high speed access is performed to read data far from the position of the current lens in the disk in the normal state, a high voltage is applied to the transfer mechanism motor M so that the pickup 5 is desired. We can go to the location where the data is located.

In the case of high-speed access to read distant data, if the voltage is increased by V ^{± 2} as in (a) of Fig. 5, it will exceed the reference voltage (V ^{± c} ). A time delay signal is generated and V ^{± 2} is applied to the feed mechanism motor (M).

Accordingly, the switch control signal generator 10 outputs the high level switch control signal as shown in FIG. 5C after t1 as shown in FIG. 5B.

Then, the movable terminal of the on / off switch SW1 is connected to ⓛ to supply the voltage V to the voltage-current converter 11.

The voltage-to-current converter 11 converts the current into a current value proportional to the input voltage and outputs the amplified voltage to the predetermined level in the current amplifier 12 to supply the electromagnet 9 above and below the actuator coil 2. .

This will have the electromagnet 9.

Accordingly, as shown in FIG. 6, when the current flows through the electromagnet 9, the N pole is formed in the direction of the permanent magnet of the electromagnet 9, whereby the N of the permanent magnet 3 is formed. And they push each other out, resulting in a holding state.

Thus, the electromagnet 9 becomes magnetic and thus interacts with the permanent magnet 3 present in the pickup 5 such that the actuator module 4 is magnetically bundled.

On the other hand, when the transfer mechanism moves and reaches a position for reading the desired data, the transfer mechanism motor (M) is cut off the voltage.

Then, the time delay signal is disconnected after t2 hours from the voltage of the transfer mechanism motor M at 0V as shown in (b) of FIG.

At this time, as the switch control signal is turned off, the on / off switch SW1 is connected to ② again, and the electromagnet loses its magnetism. Here, time t1 and time t2 can be adjusted according to the actuator characteristic.

As described in detail above, the present invention fixes the actuator in the pickup during high-speed access to prevent vibration, thereby reducing the anxiety factor of the tracking servo caused by the vibration of the actuator after the transfer mechanism stops, thereby reducing the anxiety of the servo in the normal servo state in a faster time. Data can be read from disk, reducing access time and improving the performance of related products. This is especially helpful for products that require high-speed data processing, such as CD-ROM drives.

Claims (1)

An electromagnet for preventing vibrations of the pickup, and a switch control signal generator for on / off control of the switch depending on whether a regeneration mode is carried during the transfer of the pickup; And a voltage-to-current converter for converting the switch control signal generator into a current proportional to the voltage applied thereto and supplying the current to the electromagnet through the current amplifier.