KR20060071251A - Radiation structrus for lens holder of optical pick up actuator - Google Patents

Abstract

The present invention is to reduce the transfer of heat generated from the coil adjacent to the lens holder to the objective lens in the optical pickup actuator, the lens holder heat dissipation structure of the optical pickup actuator according to the present invention is mounted to the center of the objective lens And an optical pickup actuator having a coil holder wound on both sides and moving in multiple axes, the first heat dissipation means being stepped on both sides of a circumferential surface on which the objective lens is seated, and the lens holder to which the coils are wound. The second heat dissipation means is formed on the side surface of the coil to minimize the contact surface with the coils, thereby dissipating heat generated from the coil adjacent to the lens holder, thereby improving driving reliability by reducing heat transferred to the objective lens. It is for.

Actuator, Lens Holder, Heat Dissipation

Description

Radiation structrus for lens holder of optical pick up actuator

1A and 1B are schematic plan and front views of a conventional optical pickup actuator.

Figure 2 is a perspective view showing a lens holder heat dissipation structure of the optical pickup actuator according to an embodiment of the present invention.

Figure 3 is a detailed block diagram showing a lens holder heat dissipation structure of the optical pickup actuator according to an embodiment of the present invention.

4 is a configuration in which a coil is wound around the lens holder of the present invention.

Figure 5 (a) is a view showing a heat transfer phenomenon in the conventional lens holder, (b) is a view showing a heat transfer phenomenon according to the present invention.

<Description of the symbols for the main parts of the drawings>

201.Objective lens 202.Lens holder

204,225,232 Heat dissipation grooves 221,222 Coil support

223,231 Coil contacts 230 Bobbin

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical pickup actuator, and more particularly, to an optical pickup actuator that can minimize the transfer of heat generated from an adjacent coil of a lens holder to an objective lens.

A general optical pickup actuator moves a moving part for mounting an objective lens to maintain a constant position between the objective lens and the disc, and tracks / records information recorded on the disc by following the disc track. do. The actuator moves in the form of a movable coil by a permanent magnet magnetic field to move the objective lens to a desired position. At this time, the movable part must translate in two directions perpendicular to each other, focusing and tracking direction, and to be made without unnecessary vibration, such as rotation or twisting to reduce the error of the optical signal.

1 is a block diagram showing a conventional optical pickup actuator.

Referring to FIG. 1, a lens holder 102 in which an objective lens 101 is mounted at a center portion and coils 105 and 106 are wound around the outer peripheral surface for tracking and focusing, and a coil of the lens holder 102 is formed. Magnets (103) and yokes (Yoke, 104) installed in the base (105) facing the 105 and 106, and the upper and lower plurality of one end is fixed to the upper and lower sides of the lens holder 102 to support it A wire suspension 107 and a damper holder 109 provided at one side of the lens holder 102 to which the other end of the wire suspension 107 is fixed are provided.

Reference numeral 108 is a fixed substrate, which is formed on the upper and lower portions of the lens holder 102 so that one end of the wire suspension 107 is soldered and fixed.

Referring to the accompanying drawings, a conventional optical pickup actuator as described above is as follows.

The objective lens 101 is mounted at the center of the lens holder 102, and a focusing coil 105 is wound around each corner portion of the lens holder 102 for focusing, and the left side of the lens holder 102 for tracking. The tracking coil 106 is wound around the right side center portion.

In addition, a plurality of yokes 104, which are ferromagnetic materials, protrude from the left and right sides of the lens holder 102 at positions opposite to the coils 105 and 106 to fix the magnets 103 to the front surfaces of the yokes. . The yoke 104 is integrated with the pickup base (not shown) by an integration means.

The fixing substrate 108 is coupled to the upper and lower side centers of the lens holder 102, and one end of two parallel wire suspensions 107 is soldered to each of the fixing substrates 108, and the wire suspension 107 is attached thereto. The other end of the damper holder 109 is fixed through a damper (not shown).

Here, a damper (not shown) is coupled to the damper holder 109 so as to have a rigid damping characteristic of the wire suspension 107, and a main substrate (not shown) is coupled to the outside so that the wire suspension 107 is connected to the damper holder 109. Make sure that the other end of is soldered.

 The lens holder 102 is floated by the wire suspension 107, and a current is supplied to each of the wire suspensions 107.

In the above structure, the tracking coils 106 attached to the central portions of both sides of the lens holder 102 are wound in proper directions with each other to generate magnetic flux in a predetermined direction when current flows, which is fixed to the magnet 103 and the electromagnetic force. Repulsion and repulsive force is generated by. By the repulsive force and the repulsive force, the movement of the lens holder 102 moves in the tracking direction (before and after), so that the tracking servo for correcting the tracking error is operated.

In addition, the focusing coil 105 is wound in a horizontal direction differently from the tracking coil, and when the current flows, the magnetic flux is generated in the up and down directions, and electromagnetically acts on the magnetic flux of the fixed magnet so as to be perpendicular to the coil. By generating a force, the lens holder 102 is moved in the focusing direction (up and down), so that a focusing servo for correcting this is operated.

The coils 105 and 106 are wound on the outer circumferential surface of the lens holder 102, and the coil moves together with the lens holder 102, which is referred to as a moving coil method. The movement of the magnet with the lens holder is called a moving magnet method. At this time, the moving method by magnet and coil uses Lorentz force of Fleming's left hand law.

The optical pickup actuator is used to record / reproduce information on an optical disc. In recent years, due to the rapid development of multimedia devices and the active production and dissemination of related contents, the optical pickup system can be used for optical and movie media. Pickup reliability is required.

When the optical pickup is driven for a long time, heat is generated in the coil by a current applied to the driving coil of the actuator, and the generated heat is transferred to the objective lens through the lens holder structure. In addition, since the current actuator has a form in which a plurality of coils are wound on both sides of the lens holder, a relatively large amount of heat is generated from the coils and transferred to the objective lens.

As described above, when heat generated from the coil is transferred to the objective lens for a long time, aberration becomes large, and when an excessive current is applied, a crack may occur in the objective lens due to thermal stress. Therefore, there is a need for an actuator that can reduce the heat transferred from the drive coil to the objective lens and improve the drive reliability of the pickup.

The present invention is to form a concave-convex shape on each side of the lens holder on which the coil is mounted, thereby minimizing the transfer of heat generated from the coil to the objective lens.

In addition, the present invention is to be able to block the heat transferred from the coil to the objective lens by processing the heat radiation groove on both sides in the lens seating portion located outside the beam through hole in which the objective lens is seated.

Lens holder heat dissipation structure of the optical pickup actuator of the present invention for achieving the above object,

In the optical pickup actuator having a lens holder is mounted on the center of the objective lens and the coil is wound on both sides,

First heat dissipation means formed on both sides of a circumferential surface on which the objective lens is mounted;

And a second heat dissipation means formed on the side of the lens holder around which the coils are wound, so as to have a minimum contact surface with the coils.

Preferably, the first heat dissipation means is formed on the side adjacent to the coil.

Preferably, the second heat dissipation means may include a first heat dissipation groove having stepped centers on both sides of the first coil to minimize contact with the inner center of the first coil wound around the centers of both sides of the lens holder, and the left sides of the lens holders. It characterized in that it comprises a second heat dissipation groove formed stepped both sides center in order to minimize contact with the inner center of the second coil wound on the right.

Hereinafter, with reference to the accompanying drawings as follows.

2 is a perspective view showing a lens holder heat dissipation structure of the optical pickup actuator according to the present invention.

Referring to FIG. 2, the lens holder 202 may contact the heat dissipation groove 204 formed stepwise to both sides of the lens seat 209 on which the objective lens 201 is mounted, and the coil mounted on the side thereof. The second heat dissipation groove 225 is formed stepped at both side center portions of the lens holder 202, and the third heat dissipation groove 232 is formed stepwise on both sides of the lens holder 202.

Referring to the accompanying drawings, a lens holder heat dissipation structure of an optical pickup according to an exemplary embodiment of the present invention configured as described above is as follows.

Referring to FIGS. 2 and 3, the lens holder 202 forms a lens seating portion 209 at the center thereof, and attaches the objective lens 201 to the beam passage hole 203 inside the lens seating portion 209. do. In this case, the lens seat 209 has a larger inner diameter than the outer diameter of the objective lens 201 and protrudes to support and fix the objective lens 201.

Both sides of the lens seat 209, that is, both sides adjacent to the coil, form a stepped heat dissipation groove 204. That is, even though heat generated from the adjacent coils is transferred to the objective lens 201 by the heat dissipation groove 204 of the lens seat 209, the lens mounting part 209 is moved upward in the direction of the object lens and is not directly transmitted to the objective lens.

In addition, both side surfaces of the lens holder 202 are mounted with coils, and tracking coils protruding up and down in the center of both sides of the lens holder 202 are supported by the coil supports 221 and 222. A focusing coil is wound around the bobbin 230 at left and right sides of the lens holder. Another coil may also be wound along with the focusing coil.

At this time, the first heat dissipation means is formed in the concave-convex shape on the center of both sides of the lens holder 202, that is, the surface on which the tracking coil is wound. ) Is formed as a first coil contact portion (223, 224) by protruding the portion, and the portion to be in contact with the central portion of the inner surface of the tracking coil is stepped to form a first heat radiation groove (225). Here, the first heat dissipation grooves 225 are preferably formed in a concave-convex shape or a predetermined width, the width of the first heat dissipation grooves 225 of the first coil contact portion (223, 224) It is desirable to form a structure wider than the width.

In addition, the left and right sides of both sides of the lens holder 202 inside the bobbin 230 to which the focusing coil is wound are formed to have a second heat dissipation step. Is formed by the second coil contact portion 231, and the surface contacting the center portion of the focusing coil is stepped to form the second heat dissipation groove 232. Here, it is preferable that the plurality of second heat dissipation grooves 232 are formed in a concave-convex shape or have a predetermined width, and the width of the second heat dissipation grooves 232 is formed between the upper and lower bobbins 230. It is preferable to form a structure wider than the width of the second coil contact portion 231.

As such, when the coils are wound on both sides of the lens holder 202 in which the first and second heat radiating means are formed, as shown in FIG. 4. Figure 4 shows an example of winding the coil on both sides of the lens holder according to the present invention. Here, the coils are typically mounted in various shapes such as square or trapezoidal shape.

4 illustrates a structure in which a tracking coil 206, a focusing coil 206, and a radial coil 207 are wound around central portions of both sides of the lens holder 202. As shown, the tracking coil 206 is supported by the upper and lower coil supports 221 and 222 and spaced apart from the first heat dissipation groove 225 formed stepwise into the inner space thereof. That is, since the upper and lower inner surfaces of the tracking coil 206 are contacted by the first coil contact part, the center of the inner surface of the tracking coil 206 and the first heat dissipation groove 225 do not contact each other. Accordingly, the heat generated from the tracking coil 206 can be reduced to be transmitted to the objective lens.

In addition, the focusing coil 205 and the radial coil 207 are overlapped and wound in a double, but the focusing coil 205 and the radial coil 207 are not in contact with the second heat dissipation groove 232 located on the inner side of the focusing coil 205 and the radial coil 207. Since the second heat dissipation groove 232 is stepped than the second coil contact portion 231, the second heat dissipation groove 232 does not come into contact with the inner surface of the coil center, and heat generated by the focusing coil 205 and the radial coil 207 is transferred to the objective lens. It can reduce the transmission.

Figure 5 (a) (b) shows a heat transfer phenomenon of the actuator according to the prior art and the present invention. 5A illustrates a conventional heat transfer phenomenon, in which heat generated from both side coils of the lens holder is transferred directly to the objective lens, thereby increasing the temperature of the objective lens.

In contrast, Figure 5 (b) is a heat transfer phenomenon of the present invention, after the heat generated from both side coils of the lens holder is primarily dissipated by the first and second heat radiating grooves, a relatively small amount of heat The heat is transferred to the objective lens and heat is sent back to the air by heat dissipation grooves formed at both sides of the objective lens. Accordingly, the heat transmitted to the objective lens is reduced, which can slow down the temperature rise of the objective lens, thereby improving the driving reliability of the actuator.

So far, the present invention has been described with reference to the preferred embodiments, and those skilled in the art to which the present invention pertains to the detailed description of the present invention and other forms of embodiments within the essential technical scope of the present invention. Could be implemented. Here, the essential technical scope of the present invention is shown in the claims, and all differences within the equivalent range will be construed as being included in the present invention.

According to the optical pickup actuator according to the present invention as described above, the heat transfer from the drive coil of the pickup actuator to the objective lens in a long time use environment such as movie, game media, etc. in a drive system for playing and recording a high density disk at high speed By reducing it, the driving reliability of the pickup can be secured.

Claims (3)

In the optical pickup actuator having a lens holder which is mounted to the center of the objective lens and coils are wound on both sides thereof, First heat dissipation means formed on both sides of a circumferential surface on which the objective lens is mounted; And a second heat dissipation means formed on the side of the lens holder on which the coils are wound so as to have a minimum contact surface with the coils. The method of claim 1, The first heat dissipation means is a lens holder heat dissipation structure of the optical pickup actuator, characterized in that formed on the side adjacent to both side coils of the lens holder. The method of claim 1, The second heat dissipation means may include a first heat dissipation groove having stepped centers on both side surfaces so as to minimize contact with the inner center of the first coil wound on both side center portions of the lens holder, and the left and right windings on both sides of the lens holder. The lens holder heat dissipation structure of the optical pickup actuator, characterized in that it comprises a second heat dissipation groove formed stepped in both sides to minimize contact with the inner center of the second coil.

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