KR100220963B1 - A friction preventing structure of shaft type optical pick-up actuator - Google Patents

Abstract

The present invention relates to an axial type optical pickup actuator, which is formed up and down in the center of the lens holder 80, and includes a gel injection hole 85 and a gel injection hole 85 having a wide cross section at an upper end portion and a lower end portion. The gel member 90 is applied to the outer circumferential surface of the perturbation shaft 56 of the yoke plate 50 and filled in the gel injection hole 85 to perform lubrication, and gel injection to prevent leakage of the gel member 90. An anti-friction structure composed of a gel cover 87 fitted to the upper and lower portions of the ball 85, which significantly improves the operating performance of the lens holder by preventing friction when the lens holder operates up, down, left and right along the perturbation axis. It works.

Description

Friction Resistant Structure of Axial Type Optical Pickup Actuator {A FRICTION PREVENTING STRUCTURE OF SHAFT TYPE OPTICAL PICK-UP ACTUATOR}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an axial type optical pickup actuator, and in particular, forms a gel injection hole penetrating up and down in the center of the lens holder, and inserts a gel member into the gel injection hole after inserting the perturbation shaft of the yoke plate through the gel injection hole. Therefore, the present invention relates to an anti-friction structure of an axial type optical pickup actuator which improves the performance by allowing the lens holder to operate smoothly and smoothly with respect to the perturbation shaft when the lens holder is operated in the vertical direction and the rotational direction along the perturbation shaft. .

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, a laser beam is incident on a pit recorded on the disc surface, and then the reflected light is detected through an optical system. The detected reflected light is converted into a signal and recorded on the disc surface. 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. Technology has gradually increased as it has led to laser disc players. In recent years, video and audio signals have been compressed onto CD-sized boards, leading to digital video discs (DVDs), which can be viewed and played on television in the home, bringing the DVD technology to practical use. As standardization of DVD technology is decided, products for commercialization will be developed and manufactured in earnest.

On the other hand, the configuration of the axis-type CD and DVD combined optical pick-up actuator manufactured to be able to reproduce the CD and DVD at the same time equipped with both the lens for the CD and DVD.

1 and 2, a yoke plate 10 having a laser passage hole 12 and a focusing and tracking yoke fixed to each other at a position perpendicular to a predetermined position of the yoke plate 10 are fixed to each other. 15, 14, a focusing magnet 16 fixed to an inner surface of the focusing yoke 15 to generate magnetic force, and a tracking magnet 18 fixed to an inner surface of the tracking yoke 14 to generate magnetic force. And a lens holder 20 in which a perturbation shaft 19 of precision machining is installed at a center of the yoke plate 10 at a right angle by insert molding, and a guide hole 26 into which the perturbation shaft 19 is fitted. And first and second lens arranging holes 22 and 23 having different sizes penetrating vertically through the lens holder 20 and the first lens arranging holes 22 to be fixed to the CD disk. The CD lens 32 for focusing the laser beam and the second lens settle 23 The lens for DVD 30 for focusing the laser beam on the disk for DVD, and the tracking adjustment coil 29 bonded to the outer circumferential surface of the lens holder 20 to generate an electromagnetic force in the radial direction by the magnetic force of the tracking magnet 18; And a focusing adjustment coil 28 wound around the outer circumferential surface of the fixed shaft 27 protruding to the bottom of the lens holder 20 to generate an electromagnetic force in the optical axis direction by the magnetic force of the focusing magnet 16, and the lens holder 20. And a coil PC 34 which is installed on an upper surface thereof and electrically connects the flexible PC 36 to the focusing adjustment coil 28 and the tracking adjustment coil 29.

On the other hand, four grooves 24 recessed are formed in the inner lens holder 20 at the position where the tracking adjustment coil 29 is installed, and the holder fixing piece 33 made of metal is installed in each groove 24. , The lens holder 20 is lifted with respect to the magnetic force of the tracking magnet 18 to be raised relative to the yoke plate 10.

The operation of the axial type optical pickup actuator configured as described above will be described.

As shown in FIGS. 1 and 2, a focusing and tracking state of a focus of a laser beam formed on a recording pit is detected by a photo detector on an optical system. In this case, when the focusing and tracking state is detected and a correction is necessary, the servo system transmits an electrical signal to the flexible PC 36. At this time, when a current flows to the coil PC 34 connected to the flexible PC 36 and a current flows to the focusing adjustment coil 28 and the tracking adjustment coil 29 connected to the coil PC 34, the focusing magnet 16 And the magnetic force by the tracking magnet 18 causes the focusing adjustment coil 28 and the tracking adjustment coil 29 to receive the Lorentz driving force.

As such, as the focusing adjustment coil 28 and the tracking adjustment coil 29 receive Lorentz driving force, the lens holder 20 holding the focusing and tracking adjustment coils 28 and 29 also receives Lorentz driving force. The focal size of the laser beam formed on the recording feet of the disc is adjusted while operating in the focusing direction, that is, the up and down direction, along the perturbation shaft 19 fixed to the yoke plate 10. In addition, as the lens holder 20 rotates about the perturbation shaft 19, the lens holder 20 is driven in the tracking adjustment direction, that is, the radial direction to correct the tracking error of the laser beam.

However, the above-described axial type optical pickup actuator is provided with a guide hole formed by penetrating up and down in the center of the lens holder in the perturbation shaft fixedly installed in the center of the yoke plate by insert molding, so that the lens holder is focused on the focusing adjustment coil and tracking adjustment. When receiving the Lorentz driving force by the coil, the perturbation shaft serves to guide the movement of the lens holder so that the lens holder can operate in the vertical direction or in the rotational direction. Therefore, since the guide ball operates innumerably along the perturbation shaft, there is a problem in that the performance of the lens holder due to friction between the perturbation shaft and the guide ball is significantly reduced.

The present invention has been made in view of the above, by forming a gel injection hole penetrated up and down in the center of the lens holder, and after inserting the perturbation shaft of the yoke plate through the gel injection hole to inject the gel member into the gel injection hole The objective is to improve the operating performance by allowing the lens holder to operate smoothly and smoothly with respect to the perturbation shaft.

1 is an exploded perspective view of a general shaft type optical pickup actuator.

Figure 2 is a perspective view of the combined state of the general axis type optical pickup actuator.

Figure 3 is an exploded perspective view of the friction preventing structure according to the present invention.

Figure 4 is a cross-sectional view of the coupling state of the optical pickup actuator according to the present invention.

5 is a perspective view of a state of use 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: lens holder 82: focusing adjustment coil

85: gel injection hole 87: gel cover

90 gel member 100 lens for CD

110: lens for DVD

The object of the present invention is to provide a lens holder, a lens for CDs and DVDs provided at predetermined intervals on the lens holder, a perturbation shaft coupled to a center of the lens holder, and a yoke plate provided with the perturbation shaft. A type optical pickup actuator comprising: a gel injection hole formed in a center of the lens holder in an optical axis direction, the perturbation shaft being coupled thereto, and an upper end portion and a lower end portion having a wide cross section; A gel member filled in the gel injection hole to perform lubrication; And a gel cover coupled to the upper and lower portions of the gel injection hole, thereby providing an anti-friction structure of the axial type optical pickup actuator.

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

As shown in FIG. 3 to FIG. 5, the present invention provides a lens holder 80, a CD lens 100 and a DVD lens 110 installed at predetermined intervals on the lens holder 80, and a lens holder ( A shaft type optical pickup actuator having a perturbation shaft 56 coupled to a center of the shaft 80 and a yoke plate 50 on which the perturbation shaft 56 is installed, is formed in the optical axis direction at the center of the lens holder 80. The perturbation shaft 56 is coupled, and the upper and lower ends of the gel injection hole 85 have a wide cross section; A gel member 90 filled in the gel injection hole 85 to perform lubrication; And a gel cover 87 coupled to the upper and lower portions of the gel injection hole 85.

In addition, focusing and tracking yokes 52 and 54 fixed to each other at a position perpendicular to a predetermined position of the yoke plate 50 and a focusing magnet 70 fixed to an inner surface of the focusing yoke 52 to generate magnetic force ), A tracking magnet 60 fixed to the inner surface of the tracking yoke 54 to generate magnetic force, and wound around the center bottom of the lens holder 80 to generate an electromagnetic force in the optical axis direction by the magnetic force of the focusing magnet 70. The focusing adjustment coil 82 and the tracking adjustment coil 84 fixed to the outer circumferential surface of the lens holder 80 to generate an electromagnetic force in the radial direction by the magnetic force of the tracking magnet 60 and the upper surface of the lens holder 80. And a coil PC 94 which is installed at and electrically connects the flexible PC 96 with the focusing adjustment coil 82 and the tracking adjustment coil 84.

Then, the iron piece 92 made of metal is installed on the outer circumferential surface of the lens holder 80 corresponding to the tracking magnet 60, and the lens holder 80 is lifted by the force attracted to the tracking magnet 60 to yoke plate 50. To be raised against

Looking at the process of assembling the axial optical pickup actuator, first, the gel member 90 is injected into the gel injection hole 85 of the lens holder 80, and then the gel member 90 leaks in the vertical direction. In order to block, the gel cover 87 is press-fitted into the upper and lower portions of the gel injection hole 85. As shown in FIG. 4, the gel injection hole 85 of the lens holder 80 is inserted into the perturbation shaft 56 protruding to the top of the yoke plate 50.

Hereinafter, the operation of the present invention.

The photodetector on the optical system detects the focusing and tracking states of the recording feet of the CD or DVD. Here, when the focusing and tracking state is detected and correction is necessary, when the servo system applies power to the coil PC 94 via the flexible PC 96, the focusing adjustment coil 82 provided on the outer circumferential surface of the lens holder 80 is provided. ) And the tracking adjustment coil 84. Thus, the magnetic force of the focusing magnet 70 and the tracking magnet 60 causes the focusing adjustment coil 82 and the tracking adjustment coil 84 to receive Lorentz driving force.

In this manner, as the focusing adjustment coil 82 and the tracking adjustment coil 84 are subjected to Lorentz driving force, the lens holder 80 is also subjected to Lorentz driving force along the perturbation shaft 56 fixed to the yoke plate 50. The focus size of the laser beam formed on the disk is adjusted while operating in the focusing direction, that is, the vertical direction. In addition, the lens holder 60 is rotated about the perturbation shaft 56 and rotates in the tracking adjustment direction, that is, the radial direction, to correct the tracking error of the laser beam focus.

Then, when the lens holder 80 operates in the vertical direction and the rotation direction, even if the perturbation shaft 56 operates along the gel injection hole 85 of the lens holder 80, it is applied to the outer circumferential surface of the perturbation shaft 56. Lubricated by the gel member 90 injected into the gel injection hole 85, and there is no direct friction between the perturbation shaft 56 and the gel injection hole 85 by the elastic force of the gel member 90. By doing so, the operating performance of the lens holder 80 is remarkably improved.

When the axis type optical pickup actuator according to the present invention is used, a gel injection hole penetrates up and down in the center of the lens holder, and the gel member is inserted into the gel injection hole after the perturbation shaft of the yoke plate is inserted through the gel injection hole. By injecting the gel cover into the upper and lower sides of the gel injection hole to prevent the gel member from leaking to the outside, the lens holder can be operated smoothly and smoothly with respect to the perturbation shaft, thereby improving operation performance. There is.

Claims (1)

A lens holder 80, a CD lens 100 and a DVD lens 110 installed at predetermined intervals on the lens holder 80, and a perturbation shaft 56 coupled to a center of the lens holder 80. And, in the shaft type optical pickup actuator provided with the yoke plate 50, the perturbation shaft 56 is installed, A gel injection hole 85 formed in the center of the lens holder 80 in the optical axis direction and having the perturbation shaft 56 coupled thereto, and having an upper end portion and a lower end portion having a wide cross section; A gel member 90 filled in the gel injection hole 85 to perform lubrication; And The gel cover 87 is coupled to the upper and lower portions of the gel injection hole 85; Anti-friction structure of the axial type optical pickup actuator, characterized in that consisting of.