KR100546088B1 - Driving apparatus for objective lens - Google Patents

Abstract

The present invention provides an apparatus related to an objective lens driving apparatus of an optical pickup.

An objective lens driving device for supporting an actuator movable part, which is composed of a lens holder for supporting an objective lens, so as to be displaceable with respect to a frame. The frame is disposed, stoppers are provided on the upper and left upper portions of the actuator frame, and the stopper abuts on the abutting portion, thereby restricting the operation beyond the prescribed direction in the disc direction of the movable part.

Objective lens, driving device, stopper, lens holder

Description

Objective lens driving device {DRIVING APPARATUS FOR OBJECTIVE LENS}             

1 is a perspective view showing an embodiment of an objective lens driving apparatus according to the present invention.

Fig. 2 is a perspective view of a part of the main part of the objective lens driving device removed.

3 is a perspective view of another direction of the objective lens driving device shown in FIG.

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

1 Objective lens 2 Lens holder

2 f abutment 2 b, 2 d support

2 c, 2 e Sub support 6 Suspension wire

9 frames 15 actuator frame

17 Stoppers 1 7 a, 1 7 b claw

1 7 c, 1 7 d claw

The present invention relates to an objective lens driving apparatus for optical pickup.

An optical head for optically reading or writing a signal to a signal recording medium such as a disk includes a housing, in which a semiconductor laser as a light emitting element and a photodetector as a light receiving element are assembled therein. A steel frame is arranged in the housing, and an actuator frame integrated therewith is disposed along both sides of the movable part including the lens, and is attached to the housing at the bottom of the frame.

In the lens holder of the movable portion, support portions are respectively provided on the upper side on the disk side and the lower side on the opposite side in each of the left and right side surfaces thereof. The lens holders are supported by suspension wires in these four support portions, respectively. The other end of each suspension wire is provided with a support for supporting the suspension wire, and the support is attached to the frame with screws. The lens holder supported by the suspension wire is formed in common with the coil bobbin, and a projecting contact portion is provided on the upper surface of the coil bobbin.

Moreover, the steel plate cover which covers the whole movable part is arrange | positioned at the actuator frame. Then, the upper part of the actuator frame disposed on the left and right sides of the movable part is covered by the leaf spring bent the side end of the cover. As a result, the abutting portion abuts against the folded bent inner surface of the cover at the time of operation, thereby limiting the operation beyond the prescribed portion in the disc direction. Thus, the contact part with the inner surface of a cover is comprised as a stopper mechanism.

[Patent Documents]

Special 2 0 0 0-2 5 1 2 9 8 No.

In the conventional objective lens driving apparatus, as described above, a cover made of steel sheet covering the entire movable part is attached to an actuator frame disposed near both sides of the suspension wire, and the stopper portion of the cover and the contact portion provided on the upper surface of the coil bobbin abut. It is configured to. However, in the ultra-thin optical pickup, it is necessary to reduce the size while securing the amount of clearance between the disk and the pickup cover and the amount of lens operation, and it becomes difficult to construct a stopper by the pickup cover arrangement on the magnetic circuit. have.

That is, in the conventional objective lens movable range limitation in which the cover covering the entire pickup is constituted as a stopper, the deviation in the movable range of the lens occurs due to the influence of the deviation of the attachment position of the cover with respect to the attitude controlled lens. If the deviation of the moving range occurs, the lens holder is moved up and down more than necessary, leading to increased stress on the suspension wire. In extreme cases, when an external force (impact) is applied, the contact state to the stopper may be left and right unbalanced, leading to deformation of the suspension wire.

The present invention is to provide an objective lens driving device that solves the above problem.

An abutment part is provided on the actuator moving part to install actuator frames integrated with the frame on both sides of the actuator moving part. A stopper is provided on the upper part of the actuator frame, and a stopper abuts on the abutting part. It is to limit the behavior beyond the prescribed.

1 is a perspective view showing an embodiment of an objective lens driving apparatus according to the present invention, FIG. 2 is a perspective view showing a state in which a main portion of the objective lens driving apparatus shown in FIG. 1 is removed, and FIG. 3 is an objective shown in FIG. It is a perspective view of the lens drive from the other direction.

The objective lens 1 is supported by the lens holder 2 and the bobbin 2 a is integrally formed at the end thereof. Focus coil 3 is wound around and mounted on bobbin 2 a, and tracking coils 4 and 5 are wound at predetermined positions in contact with focus coil 3 in bobbin 2 a.

In addition, in each of the left and right side surfaces of the lens holder 2, two suspension wires 6 are arranged in parallel with each other. In this case, the upper and lower sides of the objective lens driving apparatus are referred to as the upper side, the upper side, the upper side, and the upper end, and the side farther from the disk side is referred to as the lower side, the lower side, the lower side, and the lower side. A total of four suspension wires 6 become elastic supports of lens holder 2, respectively. One end of the suspension wire 6 arranged on the upper side is supported by the support part 2 b integrally formed with the lens holder 2 and the sub support part 2 c formed integrally with the lens holder 2 and provided on an extension line of the support part 2 b. One end of the suspension wire 6 disposed on the lower side is supported by the supporting portion 2d integrally formed with the lens holder 2 and the sub-supporting portion 2e formed integrally with the lens holder 2 and provided on an extension line of the supporting portion 2d. Here, the space | interval of the support part 2e and the support part 2d is set shorter than the space | interval of the support part 2c and the support part 2b.

The other end of each of the four suspension wires 6 is soldered to the support member 7 and the printed circuit board 8 attached to the support member 7, respectively. The printed board 8 and the support member 7 are fixed to the frame 9 made of steel by screws 10. In this way, the objective lens driver is elastically supported with respect to the frame 9 so as to be displaceable. Moreover, in the both side surfaces in which the lens holder 2 was inserted, the contact part 2f which protrudes toward the outward direction of the side surface is integrally formed between each support part 2b and the support part 2d.

A pair of magnets 1 1 and 1 2 are provided so that the same magnetic pole face (N pole) faces the focus coil 3 and the tracking coils 4 and 5. The pair of magnets 1 1, 1 2 are attached to opposing yokes 1 3 and 1 4 which are integrally molded with the frame 9, respectively. In addition, the actuator frame 1 5 integrated with the frame 9 is disposed along the outer sides of both sides of the suspension wire 6.

The actuator frame 15 is provided with a stopper 1 7 made of steel sheet over its upper end and lower end. The stopper 1 7 is attached to the actuator frame 1 5 by claws 1 7 a, 1 7 b having tensions at the top and claws 1 7 c, 1 7 d at the bottom. The upper part of the stopper 1 7 is provided with the edge which has the contact surface 1 7e which contact | connects the contact part 2f.

The magnetic fluxes generated in the magnets 1 1 and 1 2 act on the effective area of the focus coil 3 and the tracking coils 4 and 5. In this case, by supplying a focus error signal to the focus coil 3, the objective lens 1 can be driven together with the lens holder 2 to perform focus control for bringing a light beam into focus on the disk signal surface. In addition, by supplying a tracking error signal to each of the tracking coils 4 and 5, the tracking control of following the light beam to the signal track of the disk can be performed, and the objective lens 1 can be driven together with the lens holder 2 to trace the signal recorded on the disk. have.

In the objective lens driving device configured as described above, the position accuracy of the contact surface 1 7 e of the stopper 1 7 attached to the left and right actuator frames 1 5 integrated with the frame 9 and the position accuracy of the contact portion 2 f integrally provided with the movable part are provided. Is improved.

In the objective lens driving apparatus according to the present invention, an abutting portion is provided to the actuator movable portion, an actuator frame integrated with the frame is disposed on the left and right sides of the actuator movable portion, and a stopper is provided on the actuator frame, respectively, The stopper abuts on the contact portion to limit the operation beyond the prescribed direction in the disc direction of the movable portion. In the configuration in which the entire pickup upper portion of the prior art is covered with a cover, only a small clearance between the whole pickup and the disc can be secured, but according to the present invention, the clearance can be secured with a margin.

Conventionally, both ends of the steel plate cover attached to the frame are folded to cover the tracking coil and the focusing coil, and the folded portion is used as a leaf spring to use this as a stopper. Therefore, the cover floats due to poor adhesion, and the contact state to the stopper becomes unbalanced left and right. On the other hand, in the present invention, since the stopper is securely attached to the left and right designating positions, the reference positions to the left and right stoppers do not change, and the contact positions are the same. This has the effect of reducing the risk of leading to an increase in stress of the wire due to the moxibustion of the cover.

In addition, when the lens position is adjusted in the tangential direction to move the entire objective lens mechanism, the stopper is integrally displaced with the frame, thereby ensuring a positional relationship that is always parallel to the contact portion of the lens holder, thereby preventing the occurrence of wire deformation. The effect can be obtained.

In addition, the abutment portion is formed to be integrally formed between the upper and lower support portions of the left and right sides of the lens holder, which is excellent in strength.

Claims (4)

An objective lens driving device which supports an actuator movable part, which is composed of a lens holder for supporting an objective lens, so as to be displaceable with respect to a frame. And a stopper on each of the upper and lower left and right sides of the actuator frame, and the stopper abuts on the abutting part, thereby limiting the operation beyond the prescribed direction in the disc direction of the movable part. . The method of claim 1, An objective lens driving device, wherein abutting portions are provided on both left and right sides of the lens holder for supporting the actuator movable portion so as to be displaceable with respect to the frame. The method of claim 2, And the abutting portion is integrally formed between the upper and lower support portions of the left and right side surfaces of the lens holder and disposed. The method of claim 1, The stopper uses a steel plate and at the same time installs a claw having a tension, and is attached to the actuator frame by the claw.

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