KR19980038672A - Antifriction Structure of Optical Pickup Actuator for DVD - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical pickup actuator for a DVD, and in particular, a CD lens for mounting a CD lens 100 and a DVD lens 110 at a predetermined interval on an objective lens holder 80 to focus laser light onto a disk. In the pickup actuator, the gel injection hole 85 is formed in the center of the objective lens holder 80, the cross section of the upper end and the lower end is wide, and the yoke inserted into the gel injection hole 85 A damping gel 90 applied to the outer circumferential surface of the perturbation shaft 56 of the plate 50 and filled in the gel injection hole 85 to perform a lubrication action, and a gel to prevent leakage of the damping gel 90. Friction-resistant structure of the optical pickup actuator for DVD, characterized in that the gel cover 87 is fitted in the upper and lower portions of the injection hole 85, the objective lens holder is operated up, down, left, right along the perturbation axis Friction when By not very useful to markedly improved the operational performance of the objective lens holder, it is effective inventors.

Description

Antifriction Structure of Optical Pickup Actuator for DVD

The present invention relates to an optical pickup actuator for a DVD, and more particularly, to form a gel injection hole penetrating up and down in the center of the objective lens holder, and to insert the perturbation shaft of the yoke plate through the gel injection hole into the gel injection hole. Injecting the damping gel and inserting the gel cover into the upper and lower sides of the gel injection hole to prevent the damping gel from leaking to the outside, the objective lens holder in the up, down direction and rotation direction along the perturbation axis The present invention relates to an anti-friction structure of an optical pick-up actuator for a DVD, which prevents operation, thereby allowing the objective lens holder to operate smoothly and smoothly with respect to the perturbation shaft, thereby improving operating performance.

In general, an optical pickup actuator is installed in a vertical portion below a disc, which is an optical recording medium of various optical disc players, such as a mini disc player (MDP), a compact disc player (CDP), or a laser disc player (LDP). While moving, it detects the desired track position on the disc. At the detected track position, laser light is incident on the pit recorded on the disc surface, and then the reflected light is detected through an optical system. It is a device to play content.

As such, as optical technology gradually develops, optical reproducing technology, which compresses only a voice signal to a thin round plate CD and plays it with a CD player and provides clean sound quality instead of a tape, simultaneously reproduces a video signal and a voice signal. The technology has gradually increased with the success of laser disc players, and recently, digital video discs (DVDs, hereinafter referred to as DVDs) can be played on television in the home by compressing video and audio signals on CD-sized plates. ), The DVD technology was put into practical use, and the standardization of the DVD technology was decided, and a product for commercialization will be developed and manufactured in earnest.

On the other hand, the optical pickup actuator for the DVD is manufactured so that both the CD and the DVD lens can be reproduced at the same time, a wire type optical pickup actuator using a wire, a hinge type optical pickup actuator using a hinge Coaxial perturbation optical pickup actuators have been used, and according to some known techniques, it is known by the technical literature that the axial perturbation method is used as the optical pickup actuator for the main DVD, and therefore the CD and the DVD of the axial perturbation method are therefore known. Let's take a look at the configuration of the combined optical pickup actuator.

First, as shown in FIG. 1 and FIG. 2, a laser passage hole for focusing laser light is formed on a disk, and a yoke plate 10 forming a bottom surface and a predetermined position of the yoke plate 10 are formed. Focusing and tracking yoke 15 and 14 fixed to each other in a position symmetrically perpendicular to the focusing, Focusing magnet 16 fixed to the inner surface of the focusing yoke 15 to generate a magnetic force and the tracking yoke A tracking magnet 18 fixed to an inner surface of the oak 14 to generate a magnetic force, a perturbation shaft 19 of a precision machining that is fixed to the center of the yoke plate 10 at a right angle by insert molding, and The guide hole 26 formed in the center of the perturbation shaft 19 is fitted, and the first and second pieces having different sizes penetrated up and down so as to be positioned on the laser passage hole 12 on one side of the guide hole 26 are provided. Lens settling holes 22 and 23 and the first lens settling The lens for CD 32 which is adhesively fixed to 22 to focus the laser light on the CD disk, and the lens for DVD which is placed in the second lens arranging hole 23 and focuses the laser light on the DVD disk. ) And a tracking adjustment coil 29 which is attached to the outer circumferential surface of the objective lens holder 20 to generate a magnetic force between the tracking magnets 18 provided on the tracking yoke 14 to control the rotational and radial directions. And a magnetic force generated between the focusing magnet 16 fixed to the focusing yoke 15 and installed in a state wound around the outer circumferential surface of the fixed shaft 27 protruding to the bottom of the objective lens holder 20. Focusing adjustment coil 28 for controlling the operation of the, and is installed on the upper surface of the objective lens holder 20 electrically connecting the flexible PC 36, the focusing adjustment coil 28 and the tracking adjustment coil 29 We make with coil PC (34) to let It is.

On the other hand, the holder fixing piece of metal material which is inserted into the groove 24 recessed into the inner surface of the objective lens holder 20 is fixed to the inner surface where the tracking adjustment coil 29 is installed on the outer peripheral surface of the objective lens holder 20 ( 33) are provided so that the magnetic force is applied to the tracking magnet 18 when the objective lens holder 20 rotates about the perturbation shaft 19 so that the objective lens holder 20 can be used for CD and DVD. By pulling the objective lens holder 20 is raised relative to the yoke plate (10).

Referring to the operation of the perturbation optical pickup actuator configured in this way as follows.

As shown in Figs. 1 and 2, the focusing and tracking states of the laser beam recording pits are detected by a photo detector on an optical system. In this case, when calibration is necessary as a result of detecting the focusing and tracking states, the servo system transmits an electrical signal to the flexible PC 36. At this time, the current is energized by the flexible PC 36 and the coil PC 34 fixed to each other by soldering, and the current flows through the focusing adjusting coil 28 and the tracking adjusting coil 29 connected to the coil PC 34. The focusing adjustment coil 28 and tracking adjustment due to the magnetic force by the focusing magnet 16 and the tracking magnet 18 fixed to the focusing yoke 15 and the tracking yoke 14 of the yoke plate 10. The coil 29 is subjected to Lorentz driving force.

As described above, as the focusing adjustment coil 28 and the tracking adjustment coil 29 receive the Lorentz driving force, the objective lens holder 20 holding the adjustment coils 28 and 29 also receives the Lorentz driving force. Along the perturbation shaft 19 fixed to the oak plate 10, the objective lens holder 20 adjusts the focus on the disk while operating in the focusing direction, that is, the up and down directions, and the objective lens holder 20 is also the perturbation shaft. As it rotates with respect to (19), it rotates in the tracking adjustment direction, that is, the rotation direction, to perform the radial direction operation.

However, the above-mentioned axial perturbation optical pickup actuator has a guide hole formed by penetrating up and down in the center of the objective lens holder in the perturbation shaft fixedly installed in the center of the yoke plate by insert molding. When the Lorentz driving force is received by the coil and the tracking adjustment coil, the objective holder guides the movement of the objective lens holder so that the objective lens holder can operate in the up and down direction or in the rotational direction. The perturbation axis is inserted into the guide hole of the objective lens holder so that the objective lens holder moves in the up and down direction and rotates in the rotational direction. The guide hole of the objective lens holder moves so that it cannot count along the perturbation axis. The performance of the objective lens holder is significantly lower due to the friction between the coaxial and guide balls There were problems.

The present invention has been made in view of this point, and forms a gel injection hole penetrated up and down in the center of the objective lens holder, and the damping gel in the gel injection hole after inserting the perturbation shaft of the yoke plate through the gel injection hole In order to prevent the damping gel from leaking to the outside, the gel cover is press-fitted into the upper and lower sides of the gel injection hole so that the objective lens holder operates in the up, down direction and the rotation direction along the perturbation axis. The objective is to improve the operating performance by preventing the objective lens holder to operate smoothly and smoothly with respect to the perturbation shaft.

The purpose of the optical pickup actuator for the CD and the lens for the CD at a predetermined interval on the objective lens holder to focus the laser light on the disk, it is formed in the center of the objective lens holder, the upper side and the upper side A gel injection hole having a wide cross section at the end and a lower end, a damping gel applied to the outer circumferential surface of the perturbation shaft of the yoke plate fitted into the gel injection hole, and filled with the gel injection hole to perform a lubricating action, A feature is achieved by providing an anti-friction structure of an optical pick-up actuator for a DVD that consists of a gel cover fitted at the top and bottom of the gel injection hole to prevent leakage.

1 is an exploded perspective view of a general axis perturbation optical pickup actuator.

Figure 2 is a perspective view of the combined state of the conventional axis perturbation optical pickup actuator.

Figure 3 is an exploded perspective view of the anti-friction structure of the optical pickup actuator according to the present invention.

4 is a cross-sectional view of an engaged state of the anti-friction structure of the optical pickup actuator according to the present invention.

5 is a view showing a state of use of the anti-friction structure of the optical pickup actuator according to the present invention.

* Explanation of symbols for main parts of the drawings

50: yoke plate 52: focusing yoke

54: tracking yoke 56: perturbation shaft

60: Tracking Magnet 70: Focusing Magnet

80: objective lens holder 82: focusing adjustment coil

85: gel injection hole 87: gel cover

90: damping gel 100: CD lens

110: lens for DVD

3 to 5, the configuration of the present invention, the CD lens 100 and the DVD lens 110 is installed on the objective lens holder 80 at a predetermined interval to focus the laser light on the disk. In the optical pickup actuator for the DVD, the gel injection hole (85) and the gel injection hole (85) formed in the center of the objective lens holder 80, the upper end and the lower end has a wide cross section The damping gel 90 is applied to the outer circumferential surface of the perturbation shaft 56 of the yoke plate 50 inserted into the gel filling hole 85, and performs a lubricating action to leak the damping gel 90. It is composed of a gel cover 87 that is fitted at the top and bottom of the gel injection hole 85 to prevent.

Hereinafter, the operation of the present invention will be described in detail with reference to the accompanying drawings.

First, a process of assembling the optical pickup actuator for a DVD according to the present invention will be described. First, after the damping gel 90 is injected into the gel injection hole 85 of the objective lens holder 80, the damping gel 90 may be deteriorated. The gel cover 87 is press-fitted into the upper and lower portions of the gel injection hole 85 so as to prevent leakage to the lower portion, and in this state, the objective lens holder 80 is shown in FIG. 4. To insert the gel injection hole 85 into the perturbation shaft 56 protruding to the top of the yoke plate 50.

As described above, the operation state of the optical pickup actuator according to the present invention in the configured state detects the focusing and tracking states of the laser beam recording pits in the photo detector on the optical system. In this case, when the focusing and tracking conditions are detected and the correction is necessary, the focusing adjustment coil 82 and the tracking adjustment coil 84 are connected to a coil PC not shown in the servo system and installed on the outer circumferential surface of the objective lens holder 80. When a current flows, the focusing is caused by a magnetic force generated between the focusing magnet 70 fixed to the focusing yoke 52 of the yoke plate 50 and the tracking magnet 60 fixed to the tracking yoke 54. The regulating coil 82 and the tracking regulating coil 84 are subjected to Lorentz driving force.

As described above, as the focusing adjustment coil 82 and the tracking adjustment coil 84 receive the Lorentz driving force, the objective lens holder 80 also receives the Lorentz driving force so that the perturbation shaft 56 fixed to the yoke plate 50 is fixed. Along the gel injection hole 85 of the objective lens holder 60, the focal point is adjusted to the disk while operating in the focusing direction, that is, the up and down directions, and the objective lens holder 60 is positioned on the perturbation shaft 56. It rotates with respect to the tracking adjustment direction, that is, rotates in the rotational direction to perform a radial direction operation.

In addition, when the objective lens holder 80 is damped, the perturbation shaft 56 is a gel injection hole of the objective lens holder 80 when the objective lens holder 80 is operated in the up, down direction and the rotation direction. Even if it operates along 85, it is applied to the outer circumferential surface of the perturbation shaft 56, and is polished by the damping gel 90 injected into the gel injection hole 85, and the objective lens is applied by the self-elastic force of the damping gel 90. The friction force is reduced between the holder 80 and the perturbation shaft 56, and since the friction between the perturbation shaft 56 and the gel injection hole 85 does not exist at all, the objective lens holder 80 The operation performance of is to be significantly improved.

Therefore, when the optical pickup actuator for DVD according to the present invention is used, a gel injection hole penetrates up and down in the center of the objective lens holder, and the gel injection hole is inserted through the perturbation shaft of the yoke plate through the gel injection hole. Injecting the damping gel into the cavity and inserting the gel cover into the upper and lower sides of the gel injection hole to prevent the damping gel from leaking outside, the objective lens holder is rotated up and down along the perturbation axis. It is a very useful and effective invention to improve the operating performance by preventing the operation in the direction to allow the objective lens holder to operate smoothly and smoothly with respect to the perturbation axis.

Claims (1)

In the optical pickup actuator for DVD, which is provided with a CD lens 100 and a DVD lens 110 at predetermined intervals on the objective lens holder 80 to focus the laser light on the disc. The gel injection hole 85 is formed in the center of the upper and lower ends, the cross section of the upper end and the lower end is wide, and the perturbation shaft 56 of the yoke plate 50 fitted into the gel injection hole 85. The damping gel 90 is applied to the outer circumferential surface and filled in the gel injection hole 85 to perform a lubrication action, and is inserted in the upper and lower portions of the gel injection hole 85 to prevent leakage of the damping gel 90. The anti-friction structure of the optical pickup actuator for DVD, characterized in that the paper is composed of a gel cover (87).