JPH10162391A - Optical head actuator and its assembly - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an assembling method for an optical head actuator in which deformation of a suspension wire can be prevented at the time of assembling. SOLUTION: An actuator frame 5 is provided for housing a lens holder 3 as well as fixing a damper base 4. The hens holder 3 is assembled in a state being held by jig, plural suspension wires 6 are attached to the assembled lens holder, the lens holder 3 to which the suspension wires 6 are attached is positioned at the actuator frame fixed with the other jig, a damper base is assembled to plural suspension wires in the positioned lens holder, the assembled damper base is fixed to the actuator frame, and a damping material is injected in a damping material housing space.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an optical head actuator for recording and reproducing data on and from an optical recording medium such as an optical disk and a method of assembling the same.

[0002]

2. Description of the Related Art An example of a conventional optical head actuator will be described with reference to FIGS. 6, an optical head actuator includes a lens holder 30 for holding an objective lens 31, a focusing coil 32a and a tracking coil 32b wound around a coil bobbin provided on the lens holder 30, and an A suspension wire 34 that movably supports the damper base 33 fixedly disposed on the base 40 in the focusing direction F and the tracking direction Tr, and a pickup base that supports the damper base 33 so as to be capable of swing adjustment in the radial direction R. 3
And an actuator base 4 that supports the pickup base 35 so as to be swingably adjustable in the tangential direction Ta.
0.

In the case shown in the figure, two pairs of suspension wires 34 are provided as a whole, and a total of four suspension wires 34 are provided. By connecting the lens holder 30 and the damper base 33 on both sides of the lens holder 30, respectively. The connection is made mechanically and electrically.

[0004] The pickup base 35 is integrally formed with two yokes 35a and 35b. These yokes 35a and 35b are disposed so as to sandwich the lens holder 30 at an interval from a horizontal direction X perpendicular to the tracking direction, and an inner surface of one of the yokes 35a facing the lens holder 30 has A magnet 36 is provided. The pickup base 35 further includes a rising portion 35c for fixing the damper base 33 from the X direction.
A screw 35d which penetrates the rising portion 35c and is screwed into a screw hole 33a provided in the damper base 33; a screw 35e which penetrates the pickup base 35 from below and abuts on the lower surface of the damper base 33; And a coil spring 35f (see FIG. 7) for urging the lower surface of the upper part upward.

[0005] The actuator base 40 has a support portion 40a for the pickup base 35 so as to adjustably support the pickup base 35 in the tangential direction Ta. The actuator base 40 further includes a laser diode 40b, a beam splitter 40
c, a rising mirror 40d and a photodiode 40e. Further, the actuator base 40 is provided with a screw 4 that penetrates the actuator base 40 from below and is screwed into a screw hole provided on the lower surface of the pickup base 35.
0f, and a coil spring 40g (see FIG. 8) for urging the lower surface of the pickup base 35 upward.

A space for accommodating a gel-like vibration damping material for suppressing vibration of the plurality of suspension wires 34 is provided at both ends in the longitudinal direction of the damper base 33 which fixes one end of the plurality of suspension wires 34. Is attached. The gel cover 37 accommodates a portion near the fixing portion of the suspension wire 34, and a gel-like vibration damping material is injected into the gel cover 37.

According to the optical head actuator configured as described above, light emitted from the laser diode 40b is
After being reflected by the beam splitter 40c, it is reflected by the rising mirror 40d, and is condensed on the signal surface of an optical recording medium (not shown) via the objective lens 31. Then, the light reflected on the signal surface of the optical recording medium is reflected again by the rising mirror 40d via the objective lens 31, passes through the beam splitter 40c, and then enters the photodiode 40e. Thereby, the photodiode 40
The information recorded on the signal surface of the optical recording medium can be detected based on the output signal from e.

[0008]

The optical head actuator is assembled through the following steps. First, the lens holder 30 is assembled as shown in FIG. Next, one ends of the plurality of suspension wires 34 are attached to the lens holder 30. Subsequently, a damper base 33 is attached to the other ends of the plurality of suspension wires 34, and a gel cover 37 is attached to the damper base 33. Then, a gel-like damping material is injected into the gel cover 37. A jig such as a syringe is used for injecting the vibration damping material. Further, the assembled body assembled as described above is assembled to the pickup base 35, and this is mounted to the actuator base 40.

More specifically, the combination of the lens holder 30 and the objective lens 3
Mutually perpendicular reference lines C for defining the center position of
1 and C2 are set, and the objective lens 31 is incorporated so that the center of the objective lens 31 coincides with the intersection. On the other hand, the damper base 33 is combined with the lens holder 30 such that the center line thereof coincides with the reference line C2. Further, the damper base 33 is fixed to the pickup base 35 such that the center line of the damper base 33 coincides with a reference position set at the rising portion 35c of the pickup base 35.

However, in the above-described assembling process, the dimensional accuracy of each component must be improved in order to improve the positioning accuracy of each part, and the dimensional error of each component directly affects the assembling accuracy. There are certain problems.

[0011] In addition to the above problems, the tip of the syringe contacts the suspension wire 34 when the vibration damping material is injected, or when the pickup base 35 is assembled, When the suspension wire 34 comes into contact with the suspension wire 34,
However, there is also a problem that it is deformed.

An object of the present invention is to provide a method for assembling an optical head actuator which is effective for improving the assembling accuracy.

Another object of the present invention is to provide a method of assembling an optical head actuator that can prevent a suspension wire from being deformed during assembly.

Still another object of the present invention is to provide an actuator frame suitable for holding an assembly of a lens holder, a suspension wire, and a damper holder to prevent the suspension wire from being deformed in the above-described assembling method. It is in.

[0015]

SUMMARY OF THE INVENTION The present invention provides a lens holder for holding a lens for an optical pickup, and a damper base for supporting the lens holder so as to be vertically and horizontally displaceable via a plurality of suspension wires. And
The damper base has a fixing portion for fixing one end side of the plurality of suspension wires and a housing space for a gel-like vibration damping material for suppressing vibration of the plurality of suspension wires near the fixing portion. In the method for assembling an optical head actuator, an actuator frame having an accommodation space for fixing the damper base and accommodating the lens holder, and an opening through which incident light and reflected light to the lens can pass is prepared. Assembling the lens holder while holding it with a jig, attaching a plurality of suspension wires to the assembled lens holder, and using another jig to attach the lens holder with the suspension wire attached thereto. Steps for positioning on the fixed actuator frame Assembling the damper base with the plurality of suspension wires in the positioned lens holder; fixing the assembled damper base to the actuator frame; and controlling the damper base in the accommodation space of the damper base. Injecting a vibration material.

The actuator frame includes:
An optical axis where the center of the lens in the lens holder is to be located is set in advance, and a reference laser beam is irradiated through the opening from below the actuator frame in accordance with the optical axis, and the laser beam is The lens holder is positioned on the actuator frame so as to be incident on the center of the lens.

Further, the actuator frame has a substantially box-like shape which covers the plurality of suspension wires between the lens holder and the damper base from below and sideways, and has one end of the damper base at one end thereof. It has a receiving part.

According to the present invention, there is further provided a lens holder for holding a lens for an optical pickup, and a damper base for supporting this lens holder vertically and horizontally via a plurality of suspension wires. The damper base has a fixing portion for fixing one end sides of the plurality of suspension wires and a housing space for a gel-like vibration damping material for suppressing vibration of the plurality of suspension wires near the fixing portion. An optical head actuator comprising: an actuator frame for fixing the damper base and accommodating the lens holder, the actuator frame including the plurality of suspension wires between the lens holder and the damper base. It has a substantially box-like shape that covers from below and from the side, with one end Has a damper base of the receiving portion,
Further, an optical head actuator is provided on its side wall, which has a hole through which an injector for injecting the damping material into the accommodation space of the damper base can be inserted.

[0019]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a plan view showing an optical head actuator according to an embodiment of the present invention, FIG. 2 is a bottom view thereof, and FIG. 3 is a sectional view taken along line AA 'of FIG. Referring to FIG. 1, an optical head actuator 1 includes an actuator base 2 and an objective lens 3-1.
And a lens holder 3 having a tracking coil 3-2 and a focusing coil 3-3 (see FIG. 3), and an actuator frame 5 accommodating the lens holder 3 and the damper base 4.

Referring to FIG. 3, the optical head actuator 1 has a laser section 11 for generating a laser beam.
The laser light emitted from the laser unit 11 is applied to the beam splitter 1
The light is irradiated from 2 through an objective lens 3-1 onto an optical disk 13 which is an optical recording medium. The reflected light from the optical disk 13 enters the light receiving device 14 from the objective lens 3-1 via the beam splitter 12. That is, the light receiving device 14 receives the reflected light from the optical disc 13.

The laser section 11 and the beam splitter 12 are held on the actuator base 2. Note that the actuator base 2 is further held and fixed to the housing of the optical disk drive. A circuit board 15 is fixed to a side surface of the actuator base 2. The circuit board 15 is electrically connected to other circuit elements of the optical disk drive by a connector 16 mounted thereon.

The above-described light receiving device 14 is mounted on the lower surface of the actuator base 2. The light receiving device 14
The photodiode 14-2 is mounted on the element holder 14-1. The actuator frame 5 is provided with a cover 17 that exposes the objective lens 3-1 and covers the remaining surface.

Referring back to FIG. 1, the suspension between the lens holder 3 and the damper base 4 is connected by a plurality of suspension wires 6.
Is housed in A yoke 7 is further attached to the actuator frame 5, and a magnet 8 is combined with the yoke 7.

Referring to FIG. 4, actuator frame 5 has a receiving portion for damper base 4 on one end side of a substantially box-shaped body formed of a resin material. A support block 5 for fixing the damper base 4 with the screw 9 is provided in the receiving portion.
One. The bottom wall of the actuator frame 5 is provided with an opening 5a through which light incident on the objective lens 3-1 and reflected light can pass. Further, on both side walls of the substantially box-shaped body, support portions 2- provided on the actuator base 2 are provided.
1 (FIG. 1), a substantially semicircular projection 5-2 is provided, and a hole 5-3 through which an injector for injecting a gel-like vibration damping material is provided. . This hole 5-3
In order to restrict the vertical movement of the injector, an elliptical shape is preferable. This is to prevent a part of the injector from contacting and deforming the suspension wire 6 when the damping material is injected. The support 2-1 has the same shape as that described with reference to FIG.

The damper base 4 has a U-shape, and the leg portions on both sides thereof are hollow, and a fixing portion 4-1 for fixing one end of the suspension wire 6 is provided at a rear portion thereof. Further, on the rear wall of the damper base 4, a flexible wiring board (not shown) for soldering connection with an end of the further fixed suspension wire 6 is provided. The damper base 4 is fixed with screws 9 in a state where the leg portions on both sides are inserted into the space between both side walls of the actuator base 2 and the support block 5-1. As described below, the suspension wire 6 is attached to the damper base 4 before fixing the damper base 4 to the actuator base 2. That is,
The lens holder 3 and the damper base 4 are housed and fixed in the actuator frame 5 in a state of an assembly connected by a plurality of suspension wires 6.

A method for assembling the present optical head actuator will be described. First, two sets of yokes 7 and magnets 8 are attached to the actuator frame 5. Referring to FIG. 4, this assembling is performed by using a substantially U-shaped yoke 7-2.
The wider one of the two rising portions is inserted into a slit 5 formed in the bottom wall of the actuator frame 5.
-4 (only one is shown) is inserted from below to rise into the actuator frame 5, and the bottom wall of the yoke 7 is bonded to the lower surface of the actuator frame 5. The narrower rising portion of the yoke 7 rises into the actuator frame 5 through the opening 5a. next,
The magnet 8 is bonded to the wider rising portion of the yoke 7.

On the other hand, the lens holder 3 is assembled while being held by the jig. Next, a plurality of suspension wires 6 are attached to the assembled lens holder 3.
Subsequently, the lens holder 3 to which the suspension wire 6 is attached is positioned in the actuator frame 5 fixed by another jig. Then, the damper base 4 is attached to the ends of the plurality of suspension wires 6 in the positioned lens holder 3. In this case, the damper base 4 is also held by another jig, and the damper base 4 is fixed to the support block 5-5 of the actuator frame 5 so that the ends of the suspension wires 6 enter the hollow portions on both sides of the damper base 4. The assembling is performed by horizontally moving toward 1. Further, the assembled damper base 4 is fixed to the support block 5-1 of the actuator frame 5 with screws 9, and the suspension wire 6 is fixed to the fixing portion 4-1 of the damper base 4. Finally, a damping material is injected into the hollow space of the damper base 4 containing the suspension wire 6. This injection is performed using an injector such as a syringe through holes 5-3 on both side walls of the actuator frame 5.

In particular, the positioning of the lens holder 3 is shown in FIG.
In the actuator frame 5, an optical axis L1 that passes through a line segment S1 connecting the centers of the protrusions 5-2 on both sides of the actuator frame 5 and in which the center of the objective lens 3-1 is to be located is set in advance. Reference laser light is emitted from a laser diode LD attached to a jig (not shown) through the opening 5a from below the actuator frame 5 in accordance with the optical axis L1. A monitor camera is provided above the lens holder 3 to monitor an incident point of a reference laser beam to the objective lens 3-1. In FIG. 5, a hatched area indicates a monitor area of a monitor camera. While monitoring with the monitor camera, the laser beam for reference is incident on the center of the objective lens 3-1, that is, the lens holder 3 is held so that the optical axis L2 of the objective lens 3-1 coincides with the optical axis L1. The lens holder 3 is positioned in the actuator frame 5 by adjusting the position of the jig being adjusted.

As described above, in the present embodiment, the lens holder 3 and the damper base 4 are assembled in a state where the lens holder 3 is positioned in the actuator frame 5. Well positioned. The actuator frame 5 covers and protects the suspension wire 6 on both sides thereof. After the suspension wire 6 is attached to the lens holder 3, the suspension wire 6 is immediately accommodated in the actuator frame 5. Therefore, the suspension wire 6 is not deformed in the subsequent steps. Needless to say, the suspension wire 6 is not deformed by the injector even in the damping material injection step.

[0030]

As described above, according to the present invention, an assembling method of an optical head actuator capable of improving assembling accuracy and preventing a suspension wire from being deformed during assembling, and an actuator frame suitable for the method. Can be provided.

[Brief description of the drawings]

FIG. 1 is a plan view of an optical head actuator obtained according to the present invention.

FIG. 2 is a bottom view of the optical head actuator of FIG. 1;

FIG. 3 is a longitudinal sectional view taken along line AA ′ of FIG. 1;

FIG. 4 is a perspective view of an actuator frame used in the present invention.

FIG. 5 is a diagram for explaining a method for positioning a lens holder with respect to an actuator frame in the present invention.

FIG. 6 is an exploded perspective view of a conventional optical head actuator.

FIG. 7 is a partial cross-sectional side view for explaining a mounting structure of a damper base in FIG. 6;

FIG. 8 is a partial cross-sectional side view for explaining a mounting structure of the pickup base in FIG. 6;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Optical head actuator 2 Actuator base 3 Lens holder 3-1 Objective lens 3-2 Tracking coil 3-3 Focusing coil 4 Damper base 5 Actuator frame 6 Suspension wire 7 Yoke 8 Magnet

Claims (5)

[Claims] 1. A lens holder for holding a lens for an optical pickup, and a damper base for supporting the lens holder to be vertically and horizontally displaceable via a plurality of suspension wires, wherein the damper base is An optical head having a fixing portion for fixing one end of the plurality of suspension wires and a housing space for a gel-like vibration damping material for suppressing vibration of the plurality of suspension wires near the fixing portion; In the method for assembling an actuator, an actuator frame having an accommodation space for fixing the damper base and accommodating the lens holder, and an opening through which incident light and reflected light to the lens can pass, is prepared. Assembling the lens holder while holding the lens holder; Mounting the suspension wire, positioning the lens holder to which the suspension wire is mounted on the actuator frame fixed by another jig, and setting the plurality of suspensions in the positioned lens holder. Assembling the damper base to a wire; fixing the assembled damper base to the actuator frame; and injecting the damping material into the housing space of the damper base. How to assemble an optical head actuator. 2. The assembling method according to claim 1, wherein
In the actuator frame, an optical axis where the center of the lens in the lens holder is to be located is set in advance, and a reference laser beam is irradiated from below the actuator frame through the opening in accordance with the optical axis. Positioning the lens holder on the actuator frame so that the laser beam is incident on the center of the lens. 3. The assembly method according to claim 1, wherein the actuator frame covers the plurality of suspension wires between the lens holder and the damper base from below and from the side. A method for assembling an optical head actuator, comprising a receiving portion of the damper base at one end thereof. 4. The assembling method according to claim 3, wherein
An assembling method of an optical head actuator, wherein a side wall of the actuator frame has a hole through which an injector for injecting the damping material into the accommodation space of the damper base can be inserted. 5. A lens holder for holding a lens for an optical pickup, and a damper base for supporting the lens holder so as to be vertically and horizontally displaceable via a plurality of suspension wires. An optical head having a fixing portion for fixing one end of the plurality of suspension wires and a housing space for a gel-like vibration damping material for suppressing vibration of the plurality of suspension wires near the fixing portion; An actuator, comprising: an actuator frame for fixing the damper base and accommodating the lens holder, the actuator frame moving the plurality of suspension wires between the lens holder and the damper base from below and from the side. It has a substantially box-like shape to cover, and the damper base receiving Is part has, further to the side wall thereof, the optical head actuator and having an insertable hole of the injector to inject the damping material into the housing space of the damper base.