JPH10255292A - Apparatus for driving objective lens of optical pickup and assembling method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an apparatus for driving an objective lens of an optical pickup and an assembling method therefore whereby a lens holder is movably, elastically, highly accurately and easily supported on a supporting stage and a mounting base. SOLUTION: A lens holder 10 and a supporting stage 26 adjacent to the lens holder are integrally molded via a separable tie bar member 16. A focus coil 12 for driving and shifting the lens holder in a direction parallel to the optical axis of an objective lens, and a tracking coil 14 for driving and shifting the lens holder in a direction orthogonal to the optical axis of the objective lens are mounted on the lens holder 10. Elastic supporting members 30a-30d having terminal parts 32a, 32b for electric connection of each coil are connected between the lens holder 10 and supporting stage 26. Thereafter, the tie bar member 16 is cut and separated thereby enabling the lens holder 10 to oscillate and shift. The coils are inserted to enclose yoke parts 20a, 20b arranged to support a pair of confronting magnets 22a, 22b on a mounting base 20. The supporting stage 26 is thus fixed and assembled onto the mounting base 20.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an objective lens driving apparatus used for an optical information recording / reproducing apparatus for recording and / or reproducing information signals on an optical recording medium such as an optical disk, and an assembling method thereof. Things.

[0002]

2. Description of the Related Art Conventionally, a light beam is applied to a signal recording surface of an optical disk which is mounted on a disk drive and rotated and operated to read an information signal recorded on the optical disk or to transmit a predetermined information signal to the optical disk. As a means for writing, an optical pickup device is used.

This optical pickup device has a light source such as a semiconductor laser device, and optically records a light beam emitted from the light source via a predetermined optical device such as a collimator lens or a beam splitter and an objective lens. While focusing on the signal recording surface of the optical disk as the medium,
Various types of devices configured to detect a light beam reflected from the signal recording surface by a photodetector and write and / or read an information signal to and from the signal recording surface have been proposed and implemented. .

As described above, in the optical pickup device, the objective lens is driven and displaced in two directions, an optical axis direction (focus direction) and a direction orthogonal to the optical axis (tracking direction), by an electromagnetic driving force. A lens driving device is provided, and the light beam focuses on a signal recording surface of the optical disk to accurately scan a recording track.

In such an objective lens driving device,
As the objective lens support member for supporting the objective lens so as to be displaceable in two axial directions, for example, a support member made of four elastic round bars or a support member formed by combining parallel leaf springs in a direction orthogonal to each other is used. A device that movably supports a lens holder to which a lens is attached has been proposed.

[0006]

However, in the case of the four support members made of the elastic round bar, it is necessary to attach each support arm to a lens holder for holding the objective lens, thereby making the manufacturing complicated. There is.

A focus coil and a tracking coil provided on a lens holder, which is a movable part, are disposed in a gap of a magnetic circuit, and the lens holder can be freely displaced in a focus direction and a tracking direction by elastic deformation of a rod-shaped support member. The configuration is such that the current flowing through the focus coil controls the position of the objective lens in the focusing direction, and the current flowing through the tracking coil controls the position of the objective lens in the tracking direction.

In this case, for example, a metal wire is used as the rod-shaped support member. However, since the cross section of the metal wire is generally circular and the rigidity in two orthogonal axes is the same, the focus direction and the tracking direction are used. The vibration characteristics cannot be designed independently, and the degree of freedom in design cannot be obtained.

On the other hand, in order to supply a drive current for control to a focus coil and a tracking coil provided on a lens holder which is a movable part, it is necessary to provide a connection line between the lens holder and the fixed part.

[0010] From such a viewpoint, there has been proposed a configuration in which a printed wiring board is attached to a surface of a support member formed by combining parallel leaf springs in a direction orthogonal to each other.

However, when such a printed wiring board is used, there is a problem that resonance of the printed wiring board itself appears and the control system is likely to be unstable. Not only is the mechanism for fixing to the arm complicated, but also the number of parts is increased, and the assembling work is complicated.

The inventor of the present invention has conducted intensive studies and has found that the lens holder and the support base are formed in the same manner, including the formation of a tie bar member that enables cutting and separation of the lens holder and the support base upon completion. Using a mold, while integrally forming, in the state of coupling the lens holder and the support,
Four rod-shaped elastic support members for movably supporting the lens holder on a support base or a mounting base are set at predetermined positions, fixed by welding or bonding, and then assembled, and then the tie bar members are cut. By separating and removing, the assembly of the objective lens driving device of the optical pickup capable of elastically supporting the lens holder with respect to the support base and its mounting base by the elastic support member is achieved easily and easily. I figured out what I could do.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an objective lens driving device for an optical pickup capable of easily and movably and elastically supporting a lens holder with respect to a support base and its mounting base with high accuracy and its assembly. It is to provide a method.

[0014]

In order to achieve the above object, a method of assembling an objective lens driving device for an optical pickup according to the present invention comprises an optical pickup for optically writing or reading information on an optical disk. A lens holder that integrally holds the objective lens, and a support base,
An optical pickup comprising a plurality of elastic support members for elastically supporting the lens holder so as to be capable of being driven and displaced in a direction parallel to the optical axis of the objective lens and in a direction perpendicular to the optical axis with respect to the support base and its mounting base. In the method of assembling an objective lens driving device, a lens holder and a support table adjacent to the lens holder are integrally formed through a tie bar member that can be cut and separated, and the lens holder is driven and displaced in a direction parallel to an optical axis of the objective lens. And a tracking coil for driving and displacing in a direction orthogonal to the optical axis, and a terminal portion for electrically connecting the coils between the lens holder and the support base. After connecting the supporting member, the tie bar member is cut and separated, the lens holder is formed so as to be capable of swinging displacement, and the respective coils are mounted. Placed through to surround to the yoke portion which is arranged to support a pair of opposing magnets on over scan, and wherein the assembled fixed on said support table and mounted on the base.

Further, the objective lens driving device for an optical pickup according to the present invention includes a lens holder for integrally holding an objective lens of the optical pickup for optically writing or reading information on an optical disk, and a support base. And a plurality of elastic support members for elastically supporting the lens holder so that the lens holder can be driven and displaced in a direction parallel to the optical axis of the objective lens and in a direction perpendicular to the optical axis with respect to the support base and its mounting base. In an objective lens driving device for an optical pickup, a lens holder and a support table adjacent to the lens holder are integrally formed through a tie bar member that can be cut and separated, and the lens holder is provided on the lens holder in a direction parallel to the optical axis of the objective lens. A lens mounted with a focus coil for driving displacement and a tracking coil for driving displacement in a direction orthogonal to the optical axis; After connecting an elastic support member provided with a terminal portion for electrically connecting each of the coils with a support base, the lens holder is formed so as to be capable of swinging displacement by cutting and separating the tie bar member. The coil is inserted and arranged so as to surround a yoke portion arranged to support a pair of opposing magnets on a mounting base, and the support base is fixed on the mounting base and assembled. I do.

[0016]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view showing an apparatus for driving an objective lens of an optical pickup according to an embodiment of the present invention;

FIGS. 1 to 4 are schematic views showing one embodiment of a method of assembling the objective lens driving device for an optical pickup according to the present invention.

1 to 4, reference numeral 10 denotes a lens holder for holding an objective lens, and 20 denotes a mounting base. The lens holder 10 has an opening 10a for mounting and holding an objective lens, and An opening 10b projecting above the mounting base 20 and capable of being inserted from the outside so as to surround the yoke portions 20a, 20b to which a pair of opposed magnets 22a, 22b are mounted on the inside, respectively.
Each of them has a configuration (see FIG. 4).

However, the yoke portions 20a, 20b
Are electromagnetically coupled by a coupling member 20c at the upper end thereof. A focus coil 12 and a tracking coil 14 are mounted between the inner surface of the opening 10b of the lens holder 10 located outside the one yoke 20b and the gap between the magnets 22a and 22b. Accordingly, the lens holder 10 is provided so as to be swingably displaceable around the yoke portions 20a and 20b integrally with the focus coil 12 and the tracking coil 14 (see FIG. 4).

Further, adjacent to the lens holder 10 arranged in this way, on the mounting base 20,
The support 26 is fixedly arranged (see FIG. 4).

Therefore, in the present embodiment, the lens holder 10 and the support base 26 are connected to each other via tie-bar members 16 provided at three places so that they can be cut and separated and removed. It is molded integrally with a machine. Each tie bar member 16
As shown by reference numerals 16a and 16b, the cut portions are formed by drawing so as to be easily cut (see FIG. 1).

As described above, the lens holder 10 and the support 2
6 are integrally formed through the tie bar member 16 respectively, and the focus coil 12 and the tracking coil 14 are mounted in the opening 10b.

Next, the lens holder 10 and the support 2
6, a printed copper for electrically connecting the focus coil 12 and the tracking coil 14 and connecting the lens holder 10 to the support 26 and its mounting base 20 so as to be swingable. Four elastic support members 30a, 30b, 30
c and 30d are fixed to the lens holder 10 side and the support base 26 side by heat welding or the like as appropriate. Thereafter, the support 26 is connected to the mounting base 20.

The elastic support members 30a to 30d can be constituted by printed copper pieces 30 having the same shape, for example, as shown in FIGS. 5 (a) and 5 (b). That is, the printed copper piece 30 is connected to the wire-like supporting portion 31.
And terminal portions 32a and 32b formed at both ends thereof.

As described above, according to this embodiment, the elastic support members 30a to 30d can be easily and simply connected in a stable state. Therefore, after properly attaching the elastic support members 30a to 30d, the focus coil 12 and the tracking coil 14
After completing the wiring connection with the power supply connection system and the like, the tie bar members 16 are cut and separated at the cutting portions 16a and 16b, respectively, thereby removing the lens holder 10 in the focus direction and tracking. It can be assembled so as to be swingable in each direction.

When the tie bar members 16 are cut and separated, it is preferable to use, for example, a thermal cutter or the like so as not to give a strain to the wire-like support portions 31 of the elastic support members 30a to 30d. is there.

Accordingly, the objective lens driving device for an optical pickup according to the present invention, which is configured as described above, can easily and highly accurately and elastically support the lens holder with respect to the support base and its mounting base. be able to.

In particular, according to the assembling method of the present invention,
In recent years, the effect of contributing to facilitating the manufacture of the objective lens driving device for the optical pickup, which has been miniaturized in recent years, and reducing the manufacturing cost thereof is extremely large.

Although the preferred embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and the dimensions, shapes, structures, etc. of the respective components do not depart from the spirit of the present invention. Various design changes can be made within the scope.

[0030]

As described above, according to the objective lens driving apparatus for an optical pickup and the method for assembling the same according to the present invention, the objective lens for an optical pickup for optically writing or reading information on an optical disk. A lens holder that integrally holds the lens holder, and a support table, such that the lens holder can be driven and displaced relative to the support table and its mounting base in a direction parallel to the optical axis of the objective lens and in a direction perpendicular to the optical axis. In an assembling method of an objective lens driving device for an optical pickup having a plurality of elastic supporting members for elastically supporting, a lens holder and a supporting table adjacent thereto are integrally molded through a tie bar member capable of being cut and separated, A focus coil for driving and displacing in the direction parallel to the optical axis of the objective lens in the lens holder and for driving and displacing in a direction perpendicular to the optical axis; A tracking coil mounted,
Next, after connecting the elastic support members each having a terminal portion for electrically connecting the respective coils between the lens holder and the support base, the tie bar member is cut and separated to allow the lens holder to swing and displace. The coils are arranged so as to surround a yoke portion arranged to support a pair of opposing magnets on the mounting base, and the support is fixed on the mounting base and assembled. Movable and elastic support of the lens holder on the support base and its mounting base can be easily performed with high precision.

[Brief description of the drawings]

FIG. 1 is a schematic plan view of an objective lens driving device showing an embodiment of a method of assembling an objective lens driving device for an optical pickup according to the present invention.

FIG. 2 is a schematic front view of the objective lens driving device shown in FIG.

FIG. 3 is a schematic right side view of the objective lens driving device shown in FIG.

FIG. 4 is a sectional view of a main part of the objective lens driving device taken along line AA in FIG. 1;

5A is a schematic plan view of the elastic support member shown in FIG. 1, and FIG. 5B is a front view of FIG.

[Explanation of symbols]

 Reference Signs List 10 Lens holder 10a Opening (for objective lens arrangement) 10b Opening (for yoke insertion) 12 Focus coil 14 Tracking coil 16 Tie bar member 16a, 16b Cut 20 Mounting base 20a, 20b Yoke 20c Coupling 22a, 22b Magnet 26 support 30 printed copper piece 30a-30d elastic support member 31 wire-like support 32a, 32b terminal

Claims (2)

[Claims] 1. A lens holder for integrally holding an objective lens of an optical pickup for optically writing or reading information on or from an optical disk, and a support table, wherein the lens holder is mounted on the support table and its mounting. In a method of assembling an objective lens driving device for an optical pickup including a plurality of elastic support members that elastically support so as to be capable of being driven and displaced in a direction parallel to and perpendicular to the optical axis of the objective lens with respect to a base, The lens holder and the support table adjacent to the lens holder are integrally formed through a tie bar member that can be cut and separated, and a focus coil for driving and displacing the lens holder in a direction parallel to the optical axis of the objective lens, and orthogonal to the optical axis. A tracking coil for driving displacement in the direction is mounted, and then, between the lens holder and the support, an electric After connecting elastic support members each having a terminal portion for connection, the tie bar member is cut and separated to form the lens holder so as to be swingable, and each of the coils is mounted on a mounting base in a pair of opposed magnets. A method of assembling the objective lens driving device for an optical pickup, wherein the device is inserted and arranged so as to surround a yoke portion arranged to support the device, and the support is fixed on a mounting base. 2. A lens holder for integrally holding an objective lens of an optical pickup for optically writing or reading information on or from an optical disk, and a support table, wherein the lens holder is mounted on the support table and attached thereto. An objective lens driving device for an optical pickup, comprising: a plurality of elastic support members that elastically support the base so as to be capable of being driven and displaced in a direction parallel to the optical axis of the objective lens and in a direction perpendicular to the optical axis. A focus coil and a direction orthogonal to the optical axis for driving displacement in a direction parallel to the optical axis of the objective lens are formed on the lens holder by integral molding through a tie bar member that can be cut and separated from the adjacent support base. A tracking coil for driving and displacing the coil, and an end for electrically connecting the coils between the lens holder and the support base. After connecting the elastic support members provided with the respective portions, the tie bar members are cut and separated to form the lens holder so as to be capable of swinging displacement, and each of the coils supports a pair of opposed magnets on a mounting base. An objective lens driving device for an optical pickup, wherein the supporting base is fixedly mounted on a mounting base and is assembled so as to surround the yoke portion disposed so as to surround the yoke portion.