JP2000113478A - Objective lens drive assembly - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve assembly workability and to enhance production efficiency by providing the drive assembly with coils for respective driving an objective lens in a focusing direction and a tracking direction and projectingly providing the outer peripheral surface of an objective lens holding body 4 for holding the objective lens with coil winding guides and directly winding the coils thereto. SOLUTION: The opposite two surfaces on the long side of the outer peripheral surface of the objective lens holding body 4 are projectingly provided with the coil winding guides 14 for winding the focusing coils 8 and the opposite two surfaces on the short side with the coil winding guides 15 for winding the tracking coils 9. The focusing coils 8 and the tracking coils 9 are respectively directly wound around the winding guides 14 and 15 to be projectingly disposed on the outer peripheral surface of the objective lens holding body 4. The coil winding guides 14 and 15 are molded of a resin integrally with the objective lens holding body 4. These guide are respectively projected perpendicularly from the outer peripheral surface of the objective lens holding body 4 and are formed in continuation with the front ends of the axial central parts to be wound with the coils.

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 device for performing focusing and tracking operations of an objective lens in an optical device of an optical recording / reproducing apparatus.

[0002]

2. Description of the Related Art FIG. 1 shows an optical device used in an optical recording / reproducing apparatus. This optical device includes various elements (laser diode) for irradiating a laser beam on a signal recording surface of an optical disc to perform optical recording and reproduction on an optical device base 1 supported movably in a radial direction of the optical disc. , A photodetector, a beam splitter, etc.).

[0003] Reference numeral 2 denotes an objective lens for irradiating a laser beam emitted from a laser diode on a signal recording surface of an optical disk by focusing the laser beam. The objective lens 2 performs focusing and tracking operations on a signal recording surface of an optical disk by an objective lens driving device 3 provided on the optical device base 1.

FIG. 2 shows the configuration of the objective lens driving device 3. The objective lens 2 is fixedly held by an objective lens holder 4 having a rectangular housing. The objective lens holder 4 is formed of a resin material, and has a center hole 5 formed in the center thereof. The objective lens 2 is attached to one end of the objective lens holder 4 away from the center hole 5.

On the other hand, reference numeral 6 denotes a metal base fixed on the optical device base 1, and the objective lens holder 4 has a center hole 5 formed in a support shaft 7 erected perpendicularly to the center of the base 6. In a state of being inserted and fitted, the objective lens 2 is supported so as to be movable in the optical axis direction (focusing direction) and in a direction perpendicular to the optical axis direction (tracking direction).

As shown in FIG. 3, focusing coils 8 are attached to two opposing surfaces on the long side of the outer peripheral surface of the objective lens holder 4 and two opposing surfaces on the short side. A tracking coil 9 is attached to the surface.

The base 6 has yokes 10 and 11 erected from the base 6 so as to face the focusing coil 8 and the tracking coil 9, respectively. Magnets 12 and 13 are provided on the inner surfaces of the yokes 10 and 11, respectively. The magnetic circuit is formed between the focusing coil 8 and the tracking coil 9 by being fixed.

In this configuration, when the focusing coil 8 is energized, the objective lens holder 4 is moved in the optical axis direction of the objective lens 2 by the magnetic force between the focusing coil 8 and the magnet 12. When the focusing adjustment operation of the objective lens 2 is performed and the tracking coil 9 is energized, the objective lens holder 4 is moved by the magnetic force between the tracking coil 9 and the magnet 13 in the optical axis direction of the objective lens 2. And the tracking adjustment operation of the objective lens 2 is performed.

Conventionally, in the objective lens driving device 3 constructed as described above, the focusing coil 8 and the tracking coil 9 are wound individually and adhered to the outer peripheral surface of the objective lens holder 4 with an adhesive or the like. Was to be installed.

[0010]

As described above, in the conventional objective lens driving device, when the focusing coil 8 and the tracking coil 9 are mounted, the step of winding each of them independently and the step of winding each of them are performed. Requires a step of bonding to the outer peripheral surface of the device, which results in poor assembly workability and a problem in production efficiency. The present invention has been made to solve such a problem.

[0011]

According to the present invention, there is provided an objective lens driving apparatus comprising a coil for driving an objective lens in a focusing direction and a tracking direction, wherein the objective lens is held. A coil winding guide protrudes from the outer peripheral surface of the objective lens holder, and a coil is wound directly on the guide and attached.

With this structure, the coil can be easily attached in the assembling process of the objective lens driving device, so that the assembling workability is improved,
Production efficiency is improved.

[0013]

Embodiments of the present invention will be described below in detail with reference to the drawings. The present invention is shown in FIG.
The present invention is applied to an optical device as shown in FIG.

Here, again, the configuration of the optical device of FIG. 1 will be described. This optical device is provided on an optical device base 1 supported movably in the radial direction of the optical disc.
The optical disk is mounted with various elements (laser diode, photodetector, beam splitter, etc.) for irradiating a laser beam onto the signal recording surface of the optical disc to perform optical recording and reproduction.

Reference numeral 2 denotes an objective lens for irradiating the laser light emitted from the laser diode on the signal recording surface of the optical disc by squeezing it. The objective lens 2 performs focusing and tracking operations on a signal recording surface of an optical disk by an objective lens driving device 3 provided on the optical device base 1.

FIG. 2 shows the configuration of the objective lens driving device 3. The objective lens 2 is fixedly held by an objective lens holder 4 having a rectangular housing. The objective lens holder 4 is formed of a resin material, and has a center hole 5 formed in the center thereof. The objective lens 2 is attached to one end of the objective lens holder 4 away from the center hole 5.

On the other hand, reference numeral 6 denotes a metal base fixed on the optical device base 1. The objective lens holder 4 has a center hole 5 formed in a support shaft 7 which is provided upright at the center of the base 6. In a state of being inserted and fitted, the objective lens 2 is supported so as to be movable in the optical axis direction (focusing direction) and in a direction perpendicular to the optical axis direction (tracking direction).

As shown in FIG. 3, focusing coils 8 are attached to two opposing surfaces on the long side on the outer peripheral surface of the objective lens holder 4, and two opposing surfaces on the short side. A tracking coil 9 is attached to the surface.

The base 6 has yokes 10 and 11 erected from the base 6 so as to face the focusing coil 8 and the tracking coil 9, respectively. Magnets 12 and 13 are provided on the inner surfaces of the yokes 10 and 11, respectively. The magnetic circuit is formed between the focusing coil 8 and the tracking coil 9 by being fixed.

In this configuration, when the focusing coil 8 is energized, the objective lens holder 4 is moved in the optical axis direction of the objective lens 2 by the magnetic force between the focusing coil 8 and the magnet 12. When the focusing adjustment operation of the objective lens 2 is performed and the tracking coil 9 is energized, the objective lens holder 4 is moved by the magnetic force between the tracking coil 9 and the magnet 13 in the optical axis direction of the objective lens 2. And the tracking adjustment operation of the objective lens 2 is performed.

In the objective lens driving device 3 configured as described above, in particular, in the present invention, coil winding guides 14 and 15 are protruded from the outer peripheral surface of the objective lens holder 4 as shown in FIGS. Each of these has a focusing coil 8
And a structure in which the tracking coil 9 is directly wound.

That is, in this embodiment, the objective lens holder 4
A coil winding guide 14 around which the focusing coil 8 is wound protrudes from two opposing surfaces on the long side of the outer peripheral surface of the motor, and a tracking coil 9 is provided on two opposing surfaces on the short side. A coil winding guide 15 around which is wound is provided.

The coil winding guides 14 and 15 are formed integrally with the objective lens holder 4 by resin molding. Each of the coil winding guides 14 and 15 projects vertically from the outer peripheral surface of the objective lens holder 4 to form a shaft center around which the coil is wound. Portions 14a and 15a, and a flange portion 14 formed continuously with the ends of the shaft core portions 14a and 15a and serving as a guide plate for winding a coil with a constant thickness.
b and 15b.

The coil winding guides 14 and 15
By directly winding the focusing coil 8 and the tracking coil 9 respectively, the coils 8 and 9 are securely attached to the objective lens holder 4 in a well-formed winding shape.

As described above, in the objective lens driving device of this embodiment, the focusing coil 8 and the tracking coil 9 are wound directly on the coil winding guides 14 and 15 protruding from the outer peripheral surface of the objective lens holder 4, respectively. Since the structure is turned, both coils 8 and 9 can be easily attached in the assembling process.

That is, in the past, when attaching the two coils 8 and 9, a step of winding each of them individually and a step of bonding them to the outer peripheral surface of the objective lens holder 4 were required. In this case, the coils 8 and 9 need only be wound directly around the coil winding guides 14 and 15 on the outer peripheral surface of the objective lens holder 4, so that the conventional bonding step is not required.
As a result, the assembly workability is improved, the production efficiency is improved, and the cost is reduced.

Moreover, in this structure, the coil winding guide 14
Since the parts 15 and 15 are formed integrally with the objective lens holder 4, the number of parts does not increase, which is more advantageous in reducing costs.

Although the embodiment of the present invention has been described above, it goes without saying that the present invention is not limited to this embodiment.

[0029]

As described above, the present invention relates to an objective lens driving device including coils for driving an objective lens in a focusing direction and a tracking direction, respectively, and an outer peripheral surface of an objective lens holder for holding the objective lens. The coil winding guide is protruded from the coil, and the coil is wound directly on the coil guide. This allows the coil to be easily attached in the assembly process of the objective lens driving device. Efficiency is improved, which is advantageous for cost reduction.

[Brief description of the drawings]

FIG. 1 is a perspective view of an optical device.

FIG. 2 is a perspective view of an objective lens driving device in the optical device.

FIG. 3 is a perspective view of an objective lens holder in the objective lens driving device.

FIG. 4 is a perspective view of an objective lens holder showing an example of an embodiment of the present invention.

FIG. 5 is a plan view of the same.

[Explanation of symbols]

2 ‥‥ objective lens, 3 ‥‥ objective lens drive, 4 ‥‥
Objective lens holder, 8 ° focusing coil, 9
{Tracking coil, 14, 15} Coil winding guide, 14a, 15a {Shaft core, 14b, 15b}
‥ Flange

Claims (3)

[Claims] 1. An objective lens driving device comprising a coil for driving an objective lens in a focusing direction and a tracking direction, respectively, wherein a coil winding guide protrudes from an outer peripheral surface of an objective lens holding body holding the objective lens. An objective lens driving device, wherein the coil is wound directly around the objective lens driving device. 2. The objective lens driving device according to claim 1, wherein the coil winding guide is formed integrally with the objective lens holder. 3. The coil winding guide projects vertically from an outer peripheral surface of the objective lens holder, and is formed continuously with a shaft core around which the coil is wound and a tip of the shaft core. 2. The objective lens driving device according to claim 1, further comprising a flange portion serving as a guide for winding the coil with a constant thickness.