JP2790901B2 - Tracking mirror actuator device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a tracking mirror actuator device, and more particularly, to a wiring structure for a rotation driving coil of a tracking mirror.

(Prior Art) As is well known, an optical pickup that forms a minute spot of laser light on an optical recording medium such as an optical disk to record / reproduce and erase information has an angle adjustment of a tracking mirror. A mechanism for accurately tracing the beam spot on the optical disk is provided.

FIG. 4 is a plan view of an actuator device of the above-described tracking mirror.
A movable unit 1 for adjusting the rotation of a tracking mirror to correct a track deviation is provided.

The movable section 1 includes a tracking mirror 2, a mirror support 3 to which the mirror 2 is fixed, and drive coils 4 located at both ends of the mirror support 3.

The above-described tracking mirror 2 has a lower surface fixed to a support member 5 (see FIG. 5) formed of a viscoelastic material in the figure, and this support member 5 has one end on the lower surface of the above-mentioned tracking mirror 2 and the other. The end is fixed to the base 6 of the pickup device.

One end of a yoke 7 forming a magnetic circuit is inserted into the drive coil 4, and one side of the drive coil 4 is positioned inside a magnetic gap 9 set by the yoke 7 and the magnet 8. doing.

The movable section 1 having such a structure generates a rotational moment about the rotation center axis J by setting the direction of the current flowing through the drive coil 4, and this moment causes the rotation about the rotation center axis J. By rotating, the tracking mirror 2 is tilted and displaced.

On the other hand, a wiring for applying a current is connected to the drive coil 4 described above, and the wiring structure is such that a lead wire 10 is located on the rotation center axis of the movable unit 1 and is integrated. A structure has been proposed in which a portion on the central axis is configured to be twisted so that a change in rotational moment accompanying rotation of the movable portion 1 is reduced to zero or minimum (for example, Japanese Utility Model Laid-Open No. 63-1233).
No. 6).

(Problems to be Solved by the Invention) However, in the above-described wiring structure, there is a possibility that the rotary lead wire 10 of the movable portion 1 is disconnected.

That is, when the movable part 1 rotates, local torsional force acts on the lead wire 10 located on the rotation center axis in a concentrated manner, as shown in FIG. Therefore, the lead wire 10 located on the rotation center axis is liable to cause fatigue failure due to torsion due to repetition of rotation, and in the worst case, is disconnected.

Therefore, in order to solve such a problem, it is necessary to increase the resistance against local torsion by sufficiently increasing the length of the lead wire 10 located on the rotation center axis. With such a structure, a space for extending the lead wire in the direction of the rotation axis is required inside the tracking mirror actuator device, and the device is correspondingly increased in size.

In addition, when it is necessary to provide a rotation angle detection mechanism for the movable portion in the tracking mirror actuator device,
Parts necessary for the mechanism are added to the movable part 1, but the parts required for the mechanism are mainly provided on the back side of the tracking mirror 2 of the movable part 1, It becomes difficult to dispose the support member 5 on the back side of the part 1.

That is, in such a case, since the support member 5 is desirably provided on the rotation center axis of the movable section 1, the lead wire 10 cannot be positioned on the rotation center axis of the movable section 1.

Further, in the above-described tracking mirror actuator device, when the support member 5 is made of a viscoelastic material and provided on the back side of the movable unit 1, the movable unit 1 moves very much in directions other than the rotation direction when performing the tracking operation. Since the structure becomes easy, there is a problem that the mirror moves harmfully due to the influence of disturbance or the like. As a support method that eliminates such a problem, a method is provided in which a support mechanism (bearing, leaf spring) having sufficiently large rigidity in each direction other than rotation for performing a tracking operation is provided on the rotation center axis of the movable unit 1. However, in this case, if a lead wire is provided on the rotation center axis of the movable unit 1, there is no space for providing a support mechanism for suppressing the unstable movement of the movable unit 1, and as a result, In some cases, it may not be possible to eliminate movements other than the one rotation direction.

Therefore, for these reasons, it is difficult to prevent a disconnection accident by increasing the length of the lead wire on the rotation axis of the movable part, and it is difficult at present.

Further, the positioning of the lead wire on the rotation center axis itself is very restrictive.

Therefore, an object of the present invention is to disconnect a lead wire used for wiring without increasing a space on a rotation axis of a movable portion required for wiring in view of the problem of the wiring structure in the conventional tracking mirror actuator device described above. An object of the present invention is to provide a tracking mirror actuator device having a structure capable of preventing an accident from occurring.

(Means for Solving the Problems) In order to achieve this object, the present invention is provided in an optical information recording / reproducing apparatus for recording / reproducing and erasing information by forming a minute spot on an optical information recording medium. A tracking mirror actuator device used for performing the spot tracking operation, wherein a driving force generation unit of a movable unit including the tracking mirror and / or a rotation angle detection mechanism of the movable unit and a base side of the optical information recording / reproducing device The power supply unit is provided with a structure to electrically connect with a lead wire, and the lead wire is fixed at a position most distant from the rotation center axis in the movable portion or in the vicinity of the position. It is characterized in that it has a wiring structure that is wound around the rotation center axis by at least a half turn and fixed to the base.

Further, the present invention is characterized in that the lead wire is a sufficiently thin wire formed by twisting a plurality of wires.

(Operation) According to the present invention, when the movable portion is rotated, local bending does not occur with respect to the lead wire, so that bending is caused in the entire length direction and a concentrated torsional force is generated. Do not let it.

Further, according to the present invention, a stranded wire having a diameter sufficiently smaller than that of a single lead wire can provide a highly flexible lead wire.

(Embodiment) Hereinafter, an embodiment of the present invention will be described in detail with reference to FIGS.

FIG. 1 is a plan view corresponding to FIG. 4 showing a tracking mirror actuator device according to an embodiment of the present invention, in which the same components as those shown in FIG. 4 are denoted by the same reference numerals. Is put in front.

The feature of the present embodiment is that even if the lead wire connected to the drive coil of the movable part and / or the rotation angle detection mechanism of the movable part in the tracking mirror actuator device is positioned other than the center axis of the movable part, the rotation of the movable part can be achieved. To minimize the change in rotational moment associated with the motor, prevent breakage of the lead wire, and greatly improve the degree of freedom in designing the support mechanism for the movable part and the installation of the rotation angle detection mechanism. On the point.

That is, in FIG. 1, the movable portion 1 is rotatably supported by a support member 11 arranged at a position aligned with the rotation center axis, and one end of the support member 11 is supported by the mirror support 3 and The other end is fixed to a support 12 provided on the base 6, respectively.

An LE for detecting the rotation angle of the mirror B is provided on the mirror support 3 on the back side of the tracking mirror 2.
A D14 is provided, and a PSD 14 is provided at a position on the base 6 side facing the LED 13. Therefore, when the movable part 1 of the tracking mirror actuator device rotates around the rotation center axis J, the LED 13 also rotates integrally, so that P
Since the difference signal at the PSD 14 fluctuates due to a change in the light amount with respect to the SD 14, the rotation angle of the movable unit 1 can be detected by detecting this fluctuation.

On the other hand, between the movable part 1 and the base 6 of the tracking mirror actuator device, a driving coil 4 and an LED 1 are provided.
There is a wiring structure for supplying power to 3, and this structure uses two lead wires 10 each for the drive coil 4 and for the LED 13.

That is, the above-described lead wire 10 has four apex corners (reference numerals 1A, 1A in the figure) corresponding to positions farthest from the rotation center axis J in the movable part 1 having a rectangular shape in plan view.
B, 1C, and 1D), which is temporarily fixed in the middle, further extended therefrom, passes over the support member 11 on the rotation center axis J, and then sandwiches the rotation center axis J, As shown in the figure, it is fixed on the base 6 at a position opposite to the temporarily fixed portion (in the figure, reference numerals 6A, 6B, 6C,
6D position).

The above-described fixing of the lead wire 10 is performed by, for example, a viscoelastic material such as a silicone resin, so that the influence of the load concentration generated in the lead wire 10 and the fixing portion is reduced to prevent disconnection due to fatigue fracture. .

Since the present embodiment has the above-described structure, when the movable unit 1 rotates, one of the lead wires 10 which is allowed on the rotation center axis J according to the rotation direction is slackened and the other is stretched in the opposite direction. Therefore, when the movable portion 1 rotates in this manner, the rotational force acts on the lead wire 10 as a force in the extension direction, and by this action, the entire portion in the length direction is not subjected to local torsion. Tension deformation, in other words, bending deformation occurs in the entire extension direction.

According to the present embodiment, local stress concentration of the lead wire 10, particularly concentration of torsional force can be avoided by making the movable portion of the lead wire 10 sufficiently long without increasing the wiring space in the tracking mirror actuator device. Therefore, fatigue fracture can be reduced, and thereby a disconnection accident can be prevented.

In addition, since it is fixed at a symmetrical position with respect to the rotation center axis and the overall length is sufficiently long, the change in the rotation moment when the movable part rotates, in other words, the rotation suppressing action can be minimized, In addition, the balance with respect to the rotation of the movable part can be well maintained.

In the above-described embodiment, sufficient flexibility can be ensured by using a structure in which the lead wire 10 is formed by twisting a plurality of sufficiently thin wires so that the above-described effects can be further promoted.

FIG. 3 is a side view showing another embodiment of the present invention. In this embodiment, similarly to the case shown in FIG. And a portion further extended from the fixed portion is wound around the rotation center axis J by about one turn and then fixed to the base 6.

According to this embodiment, compared to the wiring structure shown in FIG.
By further increasing the length of the movable portion of the lead wire 10, that is, the extension portion that is linked to the rotation of the movable portion 1, local concentration of rotational force can be reduced.

In the above-described embodiment, the case where the number of the lead wires 10 is four in total has been described. However, it is needless to say that the present invention is not limited to such a case. For example, there is no rotation angle detecting mechanism. In this case, it is sufficient for the drive coil only, and furthermore, when the drive coil is configured by a moving magnet installed on the base side, it is also possible to use only the rotation angle detection mechanism. In such a case, it is desirable that the fixed portion of the movable portion be symmetrical with respect to the position of the center of gravity of the movable portion.

Further, in the above-described embodiment, the structure of the viscoelastic material itself is used as the structure of the fixing portion. However, the present invention is not limited to this. For example, the lead wire is fixed using solder or an adhesive, and Thus, the cushioning effect may be obtained by covering the periphery of the solder or the adhesive with a viscoelastic material.

(Effect of the Invention) As described above, according to the present invention, the middle of the lead wire is fixed at or near the position farthest from the rotation center axis in the movable part, and the extension is fixed to the base after passing through the rotation center axis. Therefore, the length of the movable portion of the lead wire can be made sufficiently long. Therefore, the force acting upon rotation of the movable portion acts not on the local portion of the lead wire but on the entire length direction, and thereby it is possible to prevent the fatigue failure caused by the local load concentration.

According to the present invention, the length of the above-described lead wire is
This is possible without increasing the space for the wiring structure in the tracking mirror actuator device.

Further, according to the present invention, by improving the flexibility of the lead wire, the force required for the bending deformation of the lead wire can be reduced. Accordingly, it is possible to minimize the influence of the rotation inhibiting force on the movable portion that occurs when the lead wire is deformed, minimize the change in the rotational moment, and prevent the balance of the movable portion from rotating against being deteriorated.

[Brief description of the drawings]

FIG. 1 is a plan view for explaining a main part of a tracking mirror actuator device according to an embodiment of the present invention, FIG. 2 is a cross-sectional view taken along a line II-II in FIG. 1, and FIG. FIG. 4 is a side view for explaining another embodiment of the present invention, FIG. 4 is a plan view corresponding to FIG. 1 for explaining a main part of a conventional tracking mirror actuator device, and FIG. FIG. 6 is a cross-sectional view taken in the direction indicated by reference numeral VV, and FIG. 6 is a perspective view for explaining the operation of the wiring structure in the main part shown in FIG. 1 ... movable part, 1A, 1B, 1C, 1D ... fixed position on the movable part side
2 ... Tracking mirror, 4 ... Drive coil, 6 ...
Base, 6A, 6B, 6C, 6D: fixed position on base side, 7: yoke, 8: magnet, 10: lead wire, J: rotation center axis.

Claims (2)

(57) [Claims] 1. A tracking mirror provided in an optical information recording / reproducing apparatus for recording / reproducing and erasing information by forming a minute spot on an optical information recording medium, and used for performing the spot tracking operation. In the actuator device, a driving force generation unit of the movable unit including the tracking mirror and / or a rotation angle detection mechanism of the movable unit is electrically connected to a power supply unit provided on a base side of the optical information recording / reproducing device by a lead wire. After fixing the middle of the lead wire at the position farthest from the rotation center axis in the movable portion or in the vicinity of the position, the lead wire is wound around the rotation center axis by at least a half turn, and then the base portion is A tracking mirror actuator device comprising a wiring structure fixed to the tracking mirror actuator. 2. The tracking mirror actuator device according to claim 1, wherein the lead wire is formed by twisting a plurality of sufficiently thin wires.