JP2000090598A - Optical disk drive - Google Patents

Abstract

(57) [Problem] To prevent breakage of an optical member at the time of transportation of an optical disk device or the like with a simple configuration. In an optical disk device for moving a carriage having an optical head along a recording surface of an optical disk, a voice coil for moving the carriage when a cartridge containing the optical disk is not loaded at a loading position in the optical disk device. The motor was configured to short-circuit both ends of the coil.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical disk device.

[0002]

In recent years, the areal recording density has become 1
Optical disk devices exceeding 0 Gbit / (inch) 2 are being developed. In recent years, in order to enable high-speed data access, an optical disk device has been developed in which an optical unit including a module such as a light source is fixed to the device main body, and only the objective optical system is mounted on the movable portion, thereby reducing the weight of the movable portion. ing. The movable portion is guided by a guide rail or the like so as to slide smoothly along the recording surface of the optical disk, and is configured to move straight at a high speed by a powerful voice coil motor.

[0003] Since the movable part can slide smoothly, the movable part may be inadvertently moved due to vibration or tilt applied to the optical disk apparatus when transporting the optical disk apparatus.
In such a case, the movable portion collides with a stopper or the like, and the impact may damage the optical head. Therefore, the conventional optical disk device is provided with a dedicated fixing mechanism for fixing the movable portion to the optical disk device body during transportation. However, when such a dedicated fixing mechanism is provided, there is a problem that the device configuration of the optical disk device becomes complicated.

SUMMARY OF THE INVENTION In view of the circumstances described above, an object of the present invention is to prevent the optical head from being damaged during transportation of an optical disk device with a simple configuration.

[0005]

In order to solve the above-mentioned problems, an optical disk apparatus according to the present invention comprises an optical head, a carriage on which the optical head is mounted, and a voice coil motor for moving the carriage along the recording surface of the optical disk. And a short-circuit means for short-circuiting both ends of the coil of the voice coil motor when the cartridge is not at the loading position.

With this configuration, when the optical disk device is transported, the cartridge is not at the loading position, and thus both ends of the coil are short-circuited. If the carriage moves in such a state, an induced electromotive force is generated in the coil, and the induced electromotive force reduces the moving speed of the carriage. Therefore, even if the carriage hits a stopper or the like, the impact at that time is reduced. Thus, damage to the optical head and the like mounted on the carriage can be prevented.

In particular, the stronger the magnetic circuit of the voice coil motor is, the greater the induced electromotive force flows through the coil disposed in the magnetic circuit, and the greater the effect of reducing the impact. Further, since there is no need to provide a dedicated fixing mechanism for fixing the carriage to the optical disk device main body (when the optical disk device is transported), the device configuration is simplified.

More specifically, the short-circuit means includes: (1) a switch pressed by the cartridge when the cartridge moves to the loading position; and (2) two contacts electrically connected to both ends of the coil. And a surface. The switch is configured to short-circuit both ends of the coil by contacting the two contact surfaces.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS First, an embodiment of the present invention will be described. FIG. 1 is a perspective view showing the basic configuration of the optical disk device of this embodiment. As shown in FIG. 1, the optical disk device holds the optical disk 2 rotatably on a rotation shaft 22 a of a spindle motor 22. Optical disk 2
Has a recording surface on its lower surface. In the following description, a direction perpendicular to the surface of the optical disk 2 is referred to as a “vertical direction”.

The optical disk device 1 includes a carriage 3 that moves linearly in the radial direction of the optical disk 2 along a recording surface (lower surface) of the optical disk 2, and a device main body 1 of the optical disk device 1.
The fixed optical unit 7 is fixed to a. The carriage 3 is equipped with an objective lens 10 for converging a laser beam on the recording surface of the optical disc 2.

The optical disk 2 is accommodated in a cartridge 2a (not shown in FIG. 1) which is a thin rectangular case. FIG. 2 illustrates an insertion path of the cartridge 2a into the optical disk device 1. The cartridge 2a is inserted horizontally from the insertion opening 1b formed in the apparatus main body 1a to the back of the apparatus main body 1a ("insertion position" in the figure). Thereafter, the sheet is conveyed to a loading position located below the insertion position. At this loading position, recording and reproduction of information on the optical disk 2 are performed.

FIG. 3 is a perspective view showing a main part of the optical disk device 1. The carriage 3 is guided linearly in the radial direction of the optical disk 2 (FIG. 1) by a pair of guide rails 41 fixed to the apparatus main body 1a (FIG. 1).

A pair of driving coils 42 are fixed to both sides of the carriage 3. The pair of coils 42 are connected to each other in series. Also, a pair of guide rails 41
A pair of center yokes 43 parallel to the guide rails 41 are provided on both sides of the center rail. A U-shaped side yoke 44 is connected to each of the center yokes 43. Center yoke 43 and side yoke 44 connected
Constitutes four sides of a rectangle, and the magnet 45 is arranged inside the four sides.

The coil 42, the yokes 43 and 44, and the magnet 45 constitute a so-called voice coil motor 4. When an electric current is applied to the coil 42, the carriage 3 reciprocates in the radial direction of the optical disk 2 (FIG. 1) by the action of the magnetic field formed by the magnet 45.

Next, the optical system of the optical disk device 1 of this embodiment will be described. In the fixed optical unit 7, a semiconductor laser 18, a collimating lens 20, a composite prism assay 21, an imaging lens 23, a data detection / tracking detection sensor 24, and an APC sensor 25 are arranged.

The divergent laser beam emitted from the semiconductor laser 18 is converted into a parallel beam by the collimating lens 20. The cross-sectional shape of the parallel light beam is an elliptical shape due to the characteristics of the semiconductor laser 18, and it is inconvenient to narrow the laser light beam onto the optical disc 2 minutely. For this reason, the incident surface 21a of the composite prism assay 21 has a predetermined inclination with respect to the incident optical axis, and refracts the incident light to shape the cross-sectional shape of the parallel light beam from an oval shape to a substantially circular shape. . Further, a deflection mirror 26 is provided in the fixed optical unit 7 to guide the laser beam 13 emitted from the composite prism assay 21 to the carriage 3.

The light beam from the fixed optical unit 7 is reflected upward by a rising mirror 31 provided inside the carriage 3 and converged on the recording surface of the optical disk 2 by an objective lens 10 provided above the carriage 3. I do.
Focusing control for adjusting the focal position of the objective lens 10 to the recording surface of the optical disk 2 is performed.
The description of fine tracking control and the like for finely adjusting the position of the light spot formed on the optical disc is omitted.

The returning laser beam 13 reflected from the optical disk 2 returns in the reverse direction to the forward path,
The reflected light is incident on the composite prism assay 21.
The half mirror surface 21b of the composite prism assay 21
Transmitted light and data detection / tracking detection sensor 24
Generates reflected light toward the source and separates the laser beam on the return path. The data detection / tracking detection sensor 24 is a composite sensor that reads data information recorded on the optical disc 2 and outputs a data signal, and outputs a tracking error signal. Note that to be precise, the tracking error signal and the data signal are generated by a head amplifier circuit (not shown) and sent to a control circuit or an information processing circuit.

Next, a description will be given of a shock absorbing mechanism of the carriage 3 according to the first embodiment. As shown in FIG. 3, the coil 42 of the voice coil motor 4 for moving the carriage 3 includes an FPC board (flexible printed circuit board) 5.
Is connected to the terminal unit 6 attached to the apparatus main body 1a (FIG. 1).

FIG. 4 is a plan view showing the terminal section 6. The pair of coils 42 (FIG. 3) are connected in series with each other, and the plus and minus terminals thereof are connected to the lead patterns 61 and 62 of the terminal unit 6 via the FPC board 5, respectively. These lead patterns 61, 62
It is connected to a power supply unit (not shown) for driving the voice coil motor 4 (FIG. 3). Land portions 63 and 64, which are portions having a predetermined area, are connected to the lead patterns 61 and 62 of the terminal portion 6, respectively.

As shown in FIG. 3, a switch 8 is provided near the terminal section 6. The switch 8 has a swing lever 81 that is swingably attached to the apparatus main body 1a via a bracket 89. The swing lever 81 is formed of a conductive member, and one end in the longitudinal direction thereof is in contact with the above-mentioned lands 63, 64 (FIG. 4), and the projections 83, 84 (also formed of a conductive member). Are formed. The end of the swing lever 81 opposite to the protrusions 83 and 84 is bent upward to form an angle portion 82.

FIGS. 5 and 6 show the operation principle of the shock absorbing mechanism of the first embodiment. The switch 8 is arranged at a position where it contacts the bottom surface of the cartridge 2a from above when the cartridge 2a is loaded to the loading position (FIG. 2) of the optical disk device 1. The swing lever 81 is urged by a spring 85 in the clockwise direction in the figure (the direction in which the projections 83 and 84 come into contact with the lands 63 and 64).

When information is not recorded / reproduced (including when the optical disk device is transported), the cartridge 2a is not at the loading position but at the insertion position (FIG. 2) or is removed from the optical disk device 1. Have been.
In this case, as shown in FIG.
Is not in contact with the angle portion 82 of the switch 8,
The swing lever 81 is at a position where the swing lever 81 swings clockwise in the drawing (by the urging force of the spring 85). That is, the projections 83 and 84 are in contact with the lands 63 and 64.

Since the swing lever 81 and the projections 83 and 84 are both formed of conductive members, when the projections 83 and 84 of the switch 8 contact the lands 63 and 64, the lead patterns 61 and 62 are short-circuited. . That is, both ends of the coil 42 are short-circuited as shown in FIG.

As described above, since both ends of the coil 42 are short-circuited, the carriage 3 is not used when the optical disk apparatus 1 is transported.
, An induced electromotive force is generated in the coil 42. Since the induced electromotive force acts in the direction of decreasing the moving speed of the carriage 3, even if the carriage 3 hits a stopper (not shown), the impact can be reduced.

On the other hand, when information is recorded / reproduced, the cartridge 2a is located at the loading position. In this case, as shown in FIG. 6A, since the cartridge 2a is in contact with the angle portion 82 of the switch 8 from above, the swing lever 81 is at a position which has swung counterclockwise in the figure. That is, the projections 83 and 84 and the lands 63 and 6
4 away. Therefore, both ends of the coil 42 are not short-circuited (FIG. 6B), and the carriage 3 can be driven by power supply from a power supply mechanism (not shown).

As described above, according to the optical disk device of the present embodiment, when the carriage 3 suddenly moves during transportation of the optical disk device 1 or the like, the impact applied to the carriage 3 can be reduced. Therefore, it is possible to prevent the objective lens 10 and the like mounted on the carriage 3 from being damaged. Further, since there is no need to provide a mechanism for fixing the carriage 3 to the apparatus main body 1a so as not to move, the apparatus configuration can be simplified.

Although only one coil 42 is shown in FIGS. 5B and 6B, this is because two coils 42 provided on both sides of the carriage 3 (FIG. 3) are connected in series. , And can be electrically regarded as one coil.

Next, a second embodiment of the present invention will be described. FIG. 7 is a diagram illustrating a switch 80 according to the second embodiment. In the second embodiment, the position where the cartridge 2a is inserted horizontally from the insertion slot 1b ("insertion position" in FIG. 2) is the loading position. The switch operation is performed by the horizontal movement of the cartridge 2a.
The switch 80 of this embodiment has a mountain-shaped angle portion 86 having a predetermined inclined surface 86a and a gentle upper end 86b. The switch 80 is the same as the switch 8 of the first embodiment except for the configuration of the angle part.

FIGS. 8 and 9 show the operation principle of the shock absorbing mechanism of the second embodiment. When the cartridge 2a is loaded to the loading position, the leading end surface of the cartridge 2 first comes into contact with the inclined portion 86a of the angle portion 86 of the switch 80, and swings the swing lever 81 counterclockwise in the figure (FIG. 8A). ). When the cartridge 2a reaches the loading position, the bottom surface of the cartridge 2 comes into contact with the upper end 86b of the angle portion 86 of the switch 80 (FIG. 9A).

When information is not recorded / reproduced,
As shown in FIG. 8A, since the cartridge 2a does not contact the angle portion 86 of the switch 8, the swing lever 81
Is located at a position pivoted clockwise in the figure (by the urging force of the spring 85), and the projections 83, 84 are in contact with the lands 63, 64. That is, both ends of the coil 42 are short-circuited (FIG. 8).
(B)).

On the other hand, when information is recorded / reproduced, the cartridge 2a is located at the loading position. In this case, as shown in FIG. 9A, the cartridge 2a contacts the angle portion 86 of the switch 8 from above,
Since the swing lever 81 is at a position where the swing lever 81 swings counterclockwise in the figure, the projections 83 and 84 are separated from the lands 63 and 64. Therefore, both ends of the coil 42 are not short-circuited (FIG. 9).
(B)), the carriage 3 can be driven by power supply from a power supply mechanism (not shown).

As described above, similarly to the first embodiment, the second
According to the optical disk device of the embodiment, when the carriage suddenly moves during transportation of the optical disk device or the like, the impact applied to the carriage can be reduced.
Further, since it is not necessary to provide a mechanism for fixing the carriage to the apparatus main body so as not to move, the apparatus configuration can be simplified.

[0034]

As described above, according to the optical disk apparatus of the present invention, even if the carriage is inadvertently moved during transportation of the optical disk apparatus, the impact applied to the carriage can be reduced. It is possible to prevent the optical member mounted on the device from being damaged. Further, since there is no need to provide a dedicated fixing mechanism for fixing the carriage to the optical disk apparatus main body, the apparatus configuration is simplified.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an optical disk device of an embodiment.

FIG. 2 is a schematic diagram of the optical disk device of FIG.

FIG. 3 is a perspective view showing a main part of the optical disk device of FIG. 1;

FIG. 4 is a plan view showing a terminal portion of the optical disc device of FIG. 1;

FIG. 5 is a schematic view showing the operation of the shock absorbing mechanism of the first embodiment.

FIG. 6 is a schematic view showing the operation of the shock absorbing mechanism of the first embodiment.

FIG. 7 is a perspective view illustrating a structure of a switch according to a second embodiment.

FIG. 8 is a schematic view showing the operation of the shock absorbing mechanism of the second embodiment.

FIG. 9 is a schematic view showing the operation of the shock absorbing mechanism of the second embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Optical disk apparatus 2 Optical disk 3 Carriage 4 Voice coil motor 42 Coil 6 Terminal part 61, 62 Lead pattern 63, 64 Land part 8 Switch 81 Swing lever 82 Angle part 83, 84 Projection 7 Fixed optical unit 10 Objective lens

Claims (8)

[Claims] An optical head having an objective lens for condensing a light beam on a recording surface of the optical disk; a carriage having the optical head mounted thereon; and a voice coil motor for moving the carriage along the recording surface of the optical disk. An optical disk device that reads at least information on the recording surface in a state where a cartridge containing the optical disk is loaded at a predetermined loading position in the optical disk device, wherein the cartridge is not at the loading position An optical disk device, further comprising short-circuit means for short-circuiting both ends of the coil of the voice coil motor. 2. When the carriage moves with both ends of the coil short-circuited, an induced electromotive force is generated in the coil, and the induced electromotive force reduces the moving speed of the carriage. The optical disk device according to claim 1. 3. The short-circuit means comprises: a switch that moves in conjunction with the movement of the cartridge to the loading position; and two contact surfaces electrically connected to both ends of the coil. 3. The optical disk device according to claim 1, wherein the switch contacts the two contact surfaces to short-circuit both ends of the coil. 4. 4. The switch is separated from the contact surface when the cartridge is at the loading position, and is in contact with the contact surface when the cartridge is not at the loading position. The optical disk device according to claim 3. 5. The optical disk apparatus according to claim 3, wherein the switch is pushed by the cartridge and moves when the cartridge moves to the loading position. 6. The optical disk device according to claim 3, wherein the contact surface is formed on a flexible wiring board for supplying power to the coil. 7. The switch has a swing lever,
7. The optical disk device according to claim 3, wherein: 8. The optical disk device according to claim 1, wherein the carriage moves straight in a radial direction of the optical disk device.