JP2002133681A - Optical pickup - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve such problem that the characteristic of an optical pickup fluctuates due to insufficiency in adhesive strength between a suspension holder and an actuator base. SOLUTION: In adhering the side surface of a suspension holder 5 which is approximately parallel to a direction in which a suspension wire 3 extends, with a projecting part 15 of an actuator base 6, the effect is promoted by facilitating an adhesive inflow process by means of a cutout part provided at the projecting part 15 and by means of irradiation with light through the cutout part.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical pickup for projecting a light spot on a disk to perform recording and reproduction.

[0002]

2. Description of the Related Art A conventional optical pickup will be described below with reference to FIGS. FIG. 4 is an exploded perspective view showing a configuration of a conventional optical pickup, and FIG. 5 is a perspective view showing a configuration of an objective lens driving device in FIG.

In FIGS. 4 and 5, reference numeral 101 denotes an objective lens driving device. The objective lens driving device 101 includes an objective lens 102 and an objective lens 102 in two axial directions perpendicular and radial to a disk (not shown). , Four suspension wires 103 movably supported by the lens, a coil 104 locked to a lens holder holding the objective lens 102 and driving the lens holder according to a drive current, and a suspension holder 1 engaged with the suspension wire 103
05, an actuator base 106 for fixing a permanent magnet forming a magnetic circuit to the suspension holder 105 and the coil 104, and a suspension wire 10 at one end.
3 is a flat electrode 10 to which a current is supplied while solder is fixed.
Flexible circuit board 10 provided with 7
8 and a reinforcing member 109 for reinforcing the mechanical strength of the planar electrode 107.

[0004] The objective lens driving device 101 includes an optical table 110.
At a predetermined position. The optical table 110
Is a not-shown optics including a beam shaping prism for adjusting the shape of a light beam emitted from the laser light source 111, a collimator lens for converting the light beam into a parallel light beam, a rising mirror for converting the direction of the light beam to an objective lens, and the like. System.

[0005] As described above, the optical pickup shown in FIG. 4 has a configuration in which the light beam emitted from the laser light source 111 reaches the objective lens 102 via the suspension holder 105.

[0006] By the way, portable recording / reproducing devices have become widespread and demands for thinning of recording / reproducing devices, such as recording / reproducing devices that can be built in portable computers, have been increasing. This request is also applied to an optical pickup provided to a recording / reproducing device.

In order to meet this demand, FIGS.
In the configuration of the optical pickup shown in (1), the suspension holder 105, the reinforcing member 109, and the planar electrode 107 are provided with cutouts for securing the optical path of the light beam, and the planar electrode 107 is electrically and / or mechanically. The same cutout is also provided in the coverlay 112 to be protected.

In order to increase the fixing strength of the suspension holder 105 to the actuator base 106, a side surface 114 of the suspension holder 105 that is substantially parallel to the suspension wire 103 and a substantially rectangular protrusion 115 provided on the actuator base 106. Adhere and fix.

[0009]

When an optical pickup is installed in a recording / reproducing apparatus for a disk, the optical pickup operates in a direction perpendicular to the information layer of the disk (focusing direction) and in a radial direction of the disk while recording or reproducing the disk. (Tracking direction). The driving force is a current supplied to the coil 104 from the actuator flexible circuit board 108. The current supplied to the coil 104 applies high-frequency vibration to the objective lens 102, and the applied high-frequency vibration is transmitted to the suspension wire 103. . The high-frequency vibration transmitted to the suspension wire 103 is transmitted to the planar electrode 112 via a soldered portion with the planar electrode 112, and the high-frequency vibration must be received by the fixed portion of the planar electrode 112 with the actuator base 106. In this case, the characteristics as an optical pickup deteriorate.

That is, in the conventional optical pickup, it is desired that the suspension holder 105 and the actuator base 106 are bonded stably to ensure the performance of the optical pickup.
5 is not sufficient only on the one surface on which the actuator base 106 is placed. Therefore, the suspension 115 is projected to the position of the actuator base 106 corresponding to both side surfaces 114 of the suspension holder 105 by bending a sheet metal. An adhesive is filled in a minute gap between the side surface 114 and the side surface 114 to secure a sufficient fixing force.

However, if a thermosetting adhesive is applied as an adhesive for obtaining a sufficient fixing force, it must be kept pressed until curing, which is not practical. When an ultraviolet-curable adhesive is applied to the adhesive, the ultraviolet light is
The gap between the suspension holder 105 and the side surface 114 of the suspension holder 105 cannot be irradiated and cannot be cured and adhered. Therefore, the side surface 1 of the suspension holder 105 that guarantees the characteristics of the optical pickup
There was a problem that high-strength bonding at 14 was virtually impossible.

SUMMARY OF THE INVENTION In view of the above problems, an object of the present invention is to provide a highly reliable optical pickup that enables high-strength bonding to an actuator base on both sides of a suspension holder.

[0013]

To solve this problem, an optical pickup according to the present invention comprises an objective lens holder having an objective lens and a coil, one end of which is fixed to the objective lens holder, and the other end of which is a suspension. Four suspension wires locked to the planar member via the holder and movably supporting the objective lens holder in two axial directions, that is, a vertical direction and a radial direction with respect to the disk, and the planar member is fixed. An actuator base having a fixing portion, and at least one of a through-hole or a through-cut portion, which is partially provided with a through-hole, is adhered to a side surface of the suspension holder substantially parallel to a direction in which the suspension wire extends. A protrusion fixed to the actuator base is provided on the actuator base through a gap substantially parallel to the side surface and filling the adhesive layer. It is formed.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS According to the first aspect of the present invention, a projection provided on an actuator base through a gap substantially parallel to the side of a suspension holder parallel to the direction in which a suspension wire extends and filled with an adhesive layer. In this configuration, the actuator base is provided with a protrusion having at least one through-hole of a through-hole or a notch in the actuator base, and the adhesive can flow from the through-hole toward the suspension holder side surface. This makes it easier to apply and flow the adhesive, and also temporarily cures with an adhesive that cures by, for example, irradiation of an energy beam such as ultraviolet light, and then increases the intensity of heat curing, irradiation of an energy beam of a different wavelength, or energy beams of the same wavelength. The bonding process such as the main curing can be performed by the method of the suspension holder and the actuator. It is possible to improve the stability and reliability of bonding between over scan, can enable the adhesion strength is high adhesion, an optical pickup having excellent environmental resistance can be provided.

[0015]

1 and 2 show an embodiment of the present invention.
This will be described with reference to FIG. FIG. 1 is an exploded perspective view of an optical pickup according to an embodiment of the present invention, and FIG. 2 is an enlarged perspective view of a main part of the optical pickup using the embodiment of FIG. FIG.
In the figure, reference numeral 1 denotes an objective lens driving device. The objective lens driving device 1 internally supports the objective lens 2 and the objective lens 2 such that the objective lens 2 can be moved in a biaxial direction perpendicular and radially to a disc (not shown). Three suspension wires,
A coil 4 which is locked to a lens holder (not shown) holding the objective lens 2 and drives the lens holder in accordance with a drive current;
The suspension holder 5 engaged with the suspension wire 3, the actuator base 6 for fixing a permanent magnet (not shown) forming a magnetic circuit to the suspension holder 5 and the coil 4, the suspension wire 3 is solder-fixed to one end and current is applied. Actuator flexible circuit board (hereinafter, referred to as ACT) having planar electrodes 7 to be supplied
-FPC) 8, a reinforcing member 9 for reinforcing the mechanical strength of the planar electrode 7, and the like.

The objective lens driving device 1 is fixed at a predetermined position on the optical bench 10. The optical bench 10 includes a beam shaping prism for adjusting the shape of a light beam emitted from the laser light source unit 11 including a light receiving element and the like, a collimator lens for converting the light beam into a parallel light beam, and a light beam in the direction of the objective lens 2. And a main bearing 19 that engages with a pair of guide rails that guide the optical pickup during driving in the recording / reproducing apparatus.
And an auxiliary bearing 20 and the like.

As shown in FIG. 1, the light beam emitted from the laser light source unit 11 reaches the objective lens 2 via the suspension holder 5. Therefore,
As described in the conventional configuration, the suspension holder 5,
The reinforcing member 9, the planar electrode 7, and the coverlay 12 that protects the planar electrode 7 electrically and / or mechanically are provided with cutouts through which light beams pass.

As shown in FIG. 2, after the reinforcing member 9, the planar electrode 7, and the cover lay 12 are respectively attached,
It is the same as the conventional configuration in that the attachment surface 13 of the suspension holder 5 and the reinforcing member 9 are attached to each other, and the suspension wire 3 is fixed to a predetermined electrode portion of the planar electrode 7 by soldering.

Further, in order to fix and fix the mounting surface of the suspension holder 5 to the actuator base 6 and to receive high-frequency vibration applied to the suspension wire 3, a side surface 14 substantially parallel to the direction in which the suspension wire 3 extends is used. The configuration for bonding and fixing to the protruding portion 15 of 6 is also the same as the conventional one.

That is, the optical pickup having the above-described configuration has the same configuration of bonding the suspension holder 5 and the actuator base 6 as described in the conventional configuration itself. Can also occur.

In order to solve the problem, the present invention uses FIGS.
As shown in FIG. 1, the protrusion 1 on the bonding surface to the side surface 14 of the suspension holder 5 provided on the actuator base 6
5 is a through-cut portion or a through-hole 21 which is either a through-hole.
This has been solved by the configuration including:

That is, after filling a gap between the side surface 14 of the suspension holder 5 and the protrusion 15 provided on the actuator base 6 with a heat-curable adhesive which is cured by heating, the penetration portion 21 extends from the penetration portion 21 toward the side surface 14. A light-curing adhesive that cures by light irradiation is applied to the penetrating side surface of the suspension holder 5 and the side surface 14 of the suspension holder 5, and the light-curing adhesive can be at least temporarily cured by irradiating light with sensitivity. For example, by completely curing the adhesive filled in advance in the gap between the protrusion 15 and the adhesive by heat treatment, the bonding process between the side surface 14 of the suspension holder 5 and the protrusion 15 can be simplified and strong adhesion can be achieved. It has the effect of making it possible. The area occupied by the protrusions 15 of the penetrating portions 21 can be set as appropriate. By applying a light-curable adhesive having a strong bonding strength as described above, the light-curable adhesive alone can be fixed, and in this case, the heat treatment step can be omitted.

In FIGS. 1 and 3, the cut-out portion has been described as the penetrating portion 21. However, even when a through-hole is formed in the main surface of the protruding portion 15, it is needless to say that the same operation and effect can be transmitted.

Further, as shown in FIG. 2, by providing a concave portion 16 in a part of the surface of the bonding surface 13, a pool of excess adhesive applied between the bonding surface 13 and the reinforcing member 9 is formed. A function can be added, and even when the amount of the applied adhesive is excessive, the excess adhesive oozes out from between the bonding surface 13 and the reinforcing member 9, and the oozing adhesive becomes the suspension wire 3.
By doing so, the suspension characteristics of the suspension wire 3 are hindered, and the possibility that the optical pickup does not operate properly can be suppressed. Further, since the concave portion 16 has a function of accumulating the adhesive, a margin can be given to the accuracy of controlling the amount of the adhesive to be applied, and the workability can be improved. Also,
When the main component of the adhesive is a thermosetting adhesive,
The adhesive accumulated in the concave portion 16 can be cured by heating, and there is no need to take care of a decrease in adhesive strength due to the uncured adhesive. Further, when a curable adhesive whose volume is shrunk by curing is applied, stronger adhesive fixation becomes possible.

The ACT-FPC shown in FIGS.
The current 8 is supplied to the planar electrode 7 from the disk side. However, the present invention is not limited to this configuration, and it goes without saying that the current shown in FIG.

[0026]

As described above, according to the present invention, since the adhesive can flow from the penetrating portion toward the side surface of the suspension holder, the flow of the adhesive can be facilitated. The adhesive can be temporarily cured with an adhesive that cures by irradiation, and then can be subjected to a bonding process such as heat curing, irradiation of energy beams of different wavelengths, or main curing by increasing the intensity of energy beams of the same wavelength. The stability and reliability of adhesion with the base can be improved,
An optical pickup with high bonding strength and high environmental resistance can be provided.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view showing an optical pickup according to an embodiment of the present invention.

FIG. 2 is an enlarged perspective view of a main part of the optical pickup in the embodiment.

FIG. 3 is an enlarged perspective view of a main part of the optical pickup in the embodiment.

FIG. 4 is an exploded perspective view showing a conventional optical pickup.

FIG. 5 is a perspective view showing an objective lens driving device in the conventional example.

FIG. 6 is an enlarged perspective view of a main part of the optical pickup in the conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Objective lens drive device 2 Objective lens 3 Suspension wire 4 Coil 5 Suspension holder 6 Actuator base 7 Planar electrode 8 Actuator flexible circuit board 9 Reinforcement member 10 Optical table 11 Laser light source unit 12 Coverlay 15 Projection 21 Penetration

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Hikaru Sakai 1006 Kazuma Kadoma, Kadoma-shi, Osaka Matsushita Electric Industrial Co., Ltd. F-term (reference) 5D118 AA06 AA12 BA01 BB02 DC03 EA02 EE05 FA29 FB15 FB20 FC10

Claims (1)

[Claims] 1. An objective lens holder having an objective lens and a coil, one end of which is fixed to the objective lens holder, and the other end of which is fixed to a planar member via a suspension holder, and which is perpendicular to the disk. Four suspension wires for movably supporting the objective lens holder in two axial directions, a radial direction, an actuator base having a fixing portion for fixing the planar member, and a partial through-hole or a notch. A protrusion that is provided with at least any one of the penetrating portions and that is fixed to a side surface of the suspension holder substantially parallel to a direction in which the suspension wire extends with an adhesive layer; An optical pickup provided on the actuator base via a gap for filling a layer.