JP2002008250A - Optical head device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical head device where external vibrations transmitted from a guide shaft to a device frame side can be controlled without lowering the precision of the slide part of the device frame sliding along the guide shaft and without raising the cost of the same. SOLUTION: A triangular expanding part 62 is formed in the device frame 6 of the optical head device 1, and the slide part 9 which slides along the main guide shaft 7 is formed at the end of the part 62. A damping material housing part 63 is formed in a position near the slide part 9 within the expanding part 62, and is filled with a damping material 64 consisting of gel-like resin. In such a case, unlike a case that a buffer material is inserted between the slide part 9 and the guide shaft 7, the vibrations transmitted from the guide shaft 7 to the device frame 6 are controlled without lowering the precision of the slide part and without raising the costs of the same.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a compact disc (CD) and a digital versatile disc (DVD).
The present invention relates to an optical head device used for reproduction of an optical recording medium such as an optical head. More specifically, the present invention relates to an optical head device having an earthquake-resistant structure in which external vibration is not transmitted to the objective lens side via the device frame.

[0002]

2. Description of the Related Art Generally, an optical head device used for reproducing an optical disk (optical recording medium) such as a CD or a DVD has
Consisting of an objective lens for converging laser light on an optical recording medium, a lens holder holding the objective lens, a lens actuator for moving the lens holder in the tracking direction and the focusing direction, and an apparatus frame on which the lens actuator is mounted. Have been.
Also, the device frame is formed with a sliding portion that slides along the guide shaft on both sides so that the device frame can move in the radial direction of the optical recording disk along the pair of guide shafts.

[0003] The guide shaft is generally mounted on an optical disk reproducing apparatus or the like on which an optical head device is mounted. Therefore, the vibration of the driving part mounted on the reproducing apparatus, the rotational vibration of the optical disk, and the like are transmitted to the optical head device via the guide shaft, and the controllability of the servo mechanism of the optical head device is hindered. There is.

In order to prevent such external vibrations from entering the optical head device, it has been proposed to arrange a buffer member between the guide shaft and a sliding portion of the device frame which slides on the guide shaft. ing. For example, the actual opening 61-69
No. 59 proposes a configuration in which an annular buffer member is inserted between an inner peripheral surface of a shaft hole formed in a slide portion on the apparatus frame side and a guide shaft passed therethrough. I have.

[0005]

However, such a conventional vibration preventing mechanism has the following problems.
First, by inserting a buffer, external vibrations can be prevented from being transmitted to the optical head device. However, since the buffer is inserted into the sliding portion, it is difficult to manufacture the sliding portion with high accuracy. In addition, since the cushioning material is inserted into the sliding portion, the structure of the portion is complicated, which leads to an increase in cost.

Further, since it is necessary to use an apparatus frame provided with a slide portion into which a buffer member is inserted, when adopting an existing optical head device, the design of the slide portion of the apparatus frame is largely changed. It is necessary and inconvenient.

SUMMARY OF THE INVENTION An object of the present invention is to propose an optical head device provided with a vibration absorbing mechanism which can be easily applied to an existing slide portion without lowering the precision of the slide portion of the device frame and increasing the cost. is there.

[0008]

In order to solve the above-mentioned problems, the present invention provides a lens actuator for moving an objective lens with respect to an optical recording medium in at least one of a tracking direction and a focusing direction, and this lens actuator comprises: An optical head device having an attached device frame, characterized in that the optical head device has a vibration absorbing material storage portion formed inside the device frame and a vibration absorbing material stored in the vibration absorbing material storage portion.

Here, the device frame includes a slide portion slidable along a guide shaft for sliding the device frame in a radial direction of the optical recording medium, and the vibration absorbing material housing is provided near the slide portion. It is desirable that the parts are arranged.

As described above, according to the present invention, since the vibration absorbing material is housed inside the device frame, the processing accuracy of the slide portion of the device frame is not reduced and the cost is not increased.
External vibrations entering through the guide shaft can be attenuated. In addition, since the vibration absorbing material accommodating portion is formed inside the device frame, when the present invention is applied to an existing device frame, it is not necessary to change the external dimensions of the device frame, so that the present invention can be easily applied. .

Here, if a fluid is employed as the vibration absorbing material, the vibration absorbing material can be easily filled from the outside into the vibration absorbing material accommodating portion inside the apparatus frame by using an injection device such as a dispenser.

Next, in addition to or in place of the above-described configuration, a vibration absorbing material accommodating portion is formed inside the guide shaft on which the sliding portion of the device frame slides along the axial direction of the guide shaft. Here, a configuration in which the vibration-absorbing material is housed can also be adopted.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of an optical head device to which the present invention is applied will be described below with reference to the drawings.

FIG. 1 is an exploded perspective view of an optical head device according to an embodiment of the present invention. The optical head device 1 of the present example is C
This is for reproducing the optical recording disk 2 such as D or DVD. The optical head device 1 includes an objective lens 3 for converging laser light on an optical recording medium, a lens holder 4 holding the objective lens 3, and a magnetically driven type for moving the lens holder 4 in a tracking direction and a focusing direction. Lens actuator 5 and device frame 6 to which lens actuator 5 is attached
It is composed of The main frame slide portion 9 and the sub shaft slide portion 10 which slide along the main guide shaft 7 and the sub guide shaft 8 indicated by imaginary lines so that the device frame 6 can reciprocate in the radial direction of the optical recording disk 2. Are formed on both sides of the device frame 6.

A rectangular actuator mounting hole 61 penetrating in the thickness direction of the device frame 6 is formed in which the lens actuator 5 is mounted.
The lens actuator 5 has a flat box-shaped actuator yoke 51 whose upper side is open, and the rotation slide shaft 52 of the lens holder 4 stands vertically from the center of this bottom plate portion. I have. The lens holder 4 is movable along the axis 52 in the focusing direction and is rotatable about the axis 52 in the tracking direction.

Lens actuator 5 and lens holder 4
Between them, a tracking magnetic drive circuit and a focusing magnetic drive circuit including a drive coil and a drive magnet are configured. Since these mechanisms are publicly known, further description is omitted in this specification.

Here, the main shaft slide portion 9 has a pair of shaft holes 91 and 92 through which the main guide shaft 7 slidably penetrates, and protrudes in a triangular shape in the device frame 6 adjacent thereto. A rectangular parallelepiped-shaped vibration-absorbing material storage portion 63 is cut out inside the portion 62 that is located. The vibration absorbing material storage section 63 stores a vibration absorbing material 64 made of a gel-like or fluid resin or the like.

In the optical head device 1 having this configuration, when an external vibration is transmitted from the main guide shaft 7 to the device frame 6, the vibration absorbing member 64 operates as described below to suppress the vibration of the device frame. When the device frame 6 vibrates, the built-in vibration absorbing material 64 is gel-like or fluid, so the phase of the vibration is delayed, and the device frame 6 vibrates in a phase opposite to that of the device frame 6. Therefore, the vibration absorbing material functions as an active damper, and the vibration of the device frame 6 is effectively suppressed.

It is to be noted that a vibration absorbing material 64 having a gel or fluidity is formed inside the apparatus frame 6.
3 can be easily filled by using an injection device such as a dispenser.

In this embodiment, the vibration absorbing member is disposed near the main shaft slide portion 9 that slides along the main guide shaft 7. In addition to this configuration, the vibration absorbing member is disposed near the sub shaft slide portion 10. A vibration absorbing material storage section may be formed in the device frame, and the vibration absorbing material may also be filled here.

Next, the vibration absorbing material may be filled or housed in the main guide shaft 7 or the sub guide shaft 8. In the example shown in FIG. 2, a vibration absorbing material storage section 71 having a circular cross section is formed inside the main guide shaft 7A over a predetermined length along the axis 7a, and is filled with a vibration absorbing material 72. The other configuration is the same as that shown in FIG. Thus, even if the vibration absorbing material is stored inside the main guide shaft 7A, the same vibration damping effect and prevention effect as in the above case can be obtained.

In addition to the main guide shaft, a similar vibration-absorbing material storage portion can be formed on the side of the sub-guide shaft 8 so that the vibration-absorbing material can be stored therein.

[0023]

As described above, the optical head device of the present invention employs a structure in which a vibration absorbing material storage portion is formed inside the device frame or inside the guide shaft, and the vibration absorbing material is stored therein. ing. Therefore, unlike the case where a buffer material or the like is inserted between the device frame and the guide shaft to suppress vibration, the vibration is transmitted from the outside via the guide shaft without lowering the accuracy of the sliding portion of the device frame and increasing the cost. Vibration can be effectively suppressed. Further, since there is no need to change the external dimensions of the device frame, the structure according to the present invention can be easily applied.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view showing an optical head device to which the present invention is applied.

FIGS. 2A and 2B are a partial perspective view and a partial sectional view showing a main part of an optical head device to which the present invention is applied.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Optical head device 2 Optical recording disk 3 Objective lens 4 Lens holder 5 Lens actuator 51 Actuator yoke 52 Sliding rotation axis 6 Device frame 61 Actuator mounting hole 62 Overhanging part 63, 71 Vibration absorbing material storage 64, 72 Vibration absorbing material

Claims (5)

[Claims] 1. An optical head device comprising: a lens actuator for moving an objective lens in at least one of a tracking direction and a focusing direction with respect to an optical recording medium; and an apparatus frame to which the lens actuator is attached. An optical head device comprising: a vibration-absorbing material storage section formed inside the vibration-absorbing material storage section; 2. The device frame according to claim 1, wherein the device frame includes a slide portion slidable along a guide shaft for sliding the device frame in a radial direction of the optical recording medium. An optical head device, wherein the vibration-absorbing material storage section is disposed. 3. The optical head device according to claim 1, wherein the vibration absorbing member is a fluid. 4. The apparatus according to claim 1, further comprising a guide shaft for reciprocating the device frame in a radial direction of the optical recording medium, wherein the guide shaft includes:
An optical head device, wherein a vibration absorbing material housing portion is formed along the axial direction of the guide shaft, and the vibration absorbing material is housed in the vibration absorbing material housing portion. 5. A lens actuator for moving an objective lens in at least one of a tracking direction and a focusing direction with respect to an optical recording medium, a device frame on which the lens actuator is mounted, and a radius of the device frame, the radius of the optical recording medium. An optical head device having a guide shaft for reciprocating in a direction, wherein a vibration absorbing material storage portion is formed inside the guide shaft along the axial direction of the guide shaft, and the vibration absorbing material is stored in the vibration absorbing material storage portion. An optical head device, wherein the optical head device is stored.