JP2002288846A - Optical pickup and disk drive apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To take sufficient measures to deal with emission of heat by efficiently radiating heat from a heat source to the outside. SOLUTION: An optical pickup 7 includes a moving base 8 consisting of a conductive material, and moves, being guided by a pair of guide shafts 5 and 6 which consist of a conductive material. A first bearing part 10 which is brought into point contact with one guide shaft and which is slidably supported by the movable base, and a second bearing parts 11, 11 which are brought into surface contact with the other guide shaft and which are slidably supported by the movable base are provided. A supported member 13 is provided, which is supported by the moving base, and which consists of a conductive material having a third bearing part 13a being brought into surface contact with one of the guide shaft.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to the technical field of an optical pickup and a disk drive.
More particularly, to the art for a disk drive apparatus having an optical pickup and which moves by being guided by the pair of guide shafts made of a conductor having a moving base consisting of a conductor.

[0002]

2. Description of the Related Art There is a disk drive device for recording and reproducing information signals on and from a disk-shaped recording medium. Such a disk drive device has a pair of guide shafts in the radial direction of a disk-shaped recording medium mounted on a disk table. An optical pickup that is guided and moved.

An example of an optical pickup in a conventional disk drive will be described below (FIG. 11).
reference).

The moving base a of the optical pickup comprises a heat transfer member b formed of a material having good heat conductivity attached to a base c formed of a resin material. Is mounted. At one end of the heat transfer member b, cylindrical bearings e, e are integrally provided, and the bearings e, e are slidably supported in surface contact with the guide shaft f. The guide shaft f is also formed of a member having good thermal conductivity like the heat transfer member b.

The base c is provided integrally with a U-shaped bearing g located on the side opposite to the side where the bearings e and e are located, and the bearing g is pointed to the guide shaft h. It is slidably supported in contact.

In an optical pickup, guide shafts f and h are mounted, for example, in parallel with a chassis (not shown), but one of the bearings g is connected in consideration of a mounting error of the guide shafts f and h to the chassis. Formed into a character shape,
When the mobile base a is moved by being guided by the guide shaft f, to h, so as to absorb the mounting error in the movable in the direction perpendicular to the axial direction relative to the guide shaft h.

[0007]

By the way, in a disk drive device, various electronic components serving as heat sources for an optical pickup, for example, a semiconductor laser or a driving IC
Since the chips and the like are arranged, it is necessary to efficiently release the heat generated from these heat sources to the outside.

In the above-mentioned conventional disk drive device, a semiconductor laser d as a heat source is attached to the heat transfer member b, and the heat generated from the semiconductor laser d is transmitted to the heat transfer member b and the bearing portions e and e. It is transmitted to the guide shaft f and discharged to the outside.

However, since the other bearing part g is formed integrally with the base part c made of a resin material,
Heat is hardly dissipated from the other guide shaft h via the bearing g. Also, even if the bearing g is formed integrally with the heat transfer member b to increase the thermal conductivity, for example, the bearing g is in point contact with the guide shaft h, so that the thermal resistance is large, and the bearing g is The amount of heat dissipated via this is very small.

Therefore, the conventional disk drive apparatus has a problem that the amount of heat dissipation is small as a whole and sufficient heat generation measures cannot be taken.

It is therefore an object of the present invention to overcome the above-mentioned problems and to efficiently release heat from a heat source to the outside to take sufficient measures against heat generation.

[0012]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, an optical pickup and a disk drive device according to the present invention have a first base that is slidably supported by a moving base in surface contact with one guide shaft. A conductor having a bearing portion and a second bearing portion slidably supported in surface contact with the other guide shaft, and having a third bearing portion supported by the moving base and point-contacted by the other guide shaft; And a supported member comprising:

Therefore, in the optical pickup and the disk drive device according to the present invention, two heat transfer paths having a sufficient heat transfer amount are secured.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the optical pickup and the disk drive device of the present invention will be described with reference to the accompanying drawings.

The disk drive device 1 includes required members and mechanisms arranged in an outer casing 2 (see FIG. 1).
The outer casing 2 has a horizontally long opening (not shown).

A chassis (not shown) is arranged in the outer casing 2, and a spindle motor 3 is attached to the chassis. A disk table 4 is fixed to a motor shaft of the spindle motor 3.

The chassis is provided with parallel guide shafts 5 and 6 made of conductors, and supports a lead screw (not shown) which is rotated by a feed motor (not shown).

The optical pickup 7 has a moving base 8 made of a conductor, necessary optical elements arranged on the moving base 8, and a biaxial actuator 9 supported on the moving base 8, and both ends of the moving base 8 A first bearing 10 and a second bearing 11, 11 provided integrally with each other are slidably supported by guide shafts 5, 6, respectively.

The first bearing portion 10 has a U-shape when viewed in cross section, and the supported pieces 10a, 10a, 10
a (see FIG. 2). Supported pieces 10a, 10a
Sliding members 12, 12 each made of an insulator are attached to the contact surface side of the guide shaft 5 with the sliding member 12, and the sliding members 12, 12 are in point contact with the guide shaft 5. Therefore, almost no heat is transmitted between the movable base 8 and the guide shaft 5 via the first bearing 10.

A guide shaft 6 is inserted into a circular supported hole of the second bearing portions 11 and 11 and is supported in a state of being in surface contact with the guide shaft 6 (see FIG. 1).

On the side of the movable base 8 on which the first bearing portion 10 is provided, a supported member 13 made of a conductor is supported spaced apart in the axial direction of the guide shaft 5 (see FIGS. 1 to 4). ). The supported member 13 is provided with a third bearing portion 13a made of a conductor that is slidably supported by being in surface contact with the guide shaft 5 (see FIGS. 2 and 4).

The supported member 13 is supported by the movable base 8 via elastic members 14 and 14 made of an insulator. As described above, the supported member 13 is moved by the movable base 8 via the insulator.
Moving base 8 and supported member 13
Heat is hardly transmitted between the two. Further, since the supported member 13 is supported by the moving base 8 via the elastic members 14, 14, the supported member 13 can be moved in a direction in which the supported member 13 is separated from and brought into contact with the moving base 8.

One end of a flexible printed wiring board 15 is connected to the movable base 8 (see FIG. 1). The other end of the flexible printed wiring board 15 is connected to a drive control circuit board (not shown) provided It is connected. Accordingly, power supply to the biaxial actuator 9 of the optical pickup 7 and each optical element, transmission and reception of various signals, and the like are performed through the flexible printed wiring board 15.

At one end of the flexible printed wiring board 15, a projection 15a protruding toward the supported member 13 is provided, and the projection 15a is mounted on the supported member 13. A driving IC chip 16 which is a heat source having a large amount of heat is mounted on the protrusion 15a attached to the supported member 13.

A nut member (not shown) provided on the moving base 8 is screwed into a lead screw, and when the lead motor is rotated by a feed motor, the nut member is sent in a direction corresponding to the rotation direction of the lead screw, and an optical pickup is provided. 7 is moved in the radial direction of the disk-shaped recording medium 100 mounted on the disk table 4.

Required optical elements are arranged on the moving base 8 (see FIG. 5).

The optical elements include a semiconductor laser (light emitting element) 17, a grating element 18, a collimator lens 19, an anamorphic prism 20, a beam splitter 21, a rising mirror 22, and an objective lens 9a provided on a two-axis actuator 9, A front photodiode 23, a light detection element 24, a condenser lens 25, a multi-lens 26, and a photodiode (light receiving element) 27.

When the laser light is emitted from the semiconductor laser 17, the emitted laser light is diffracted by the grating element 18, divided into a main beam and two sub-beams, and is incident on a collimator lens 19, where the collimator lens 19 Is converted into a parallel light beam. The laser beam converted into a parallel light beam is shaped by an anamorphic prism 20 so that the divided beam has an aspect ratio. The shaped laser beam is incident on a beam splitter 21 and is directed to a rising mirror 22 and to a front photodiode 23. It is separated into incoming light.

The light directed to the rising mirror 22 is raised by the rising mirror 22, irradiates the recording surface of the disk-shaped recording medium 100 mounted on the disk table 4 via the objective lens 9a, and returns. Is again incident on the beam splitter 21 via the objective lens 9a and the rising mirror 22.

On the other hand, the amount of light directed to the front photodiode 23 is detected, and the amount of laser light emitted from the semiconductor laser 17 is controlled based on the detected amount so as to be constant.

The return light incident on the beam splitter 21 via the objective lens 9a and the rising mirror 22 is
Information reflected on the reflection surface of the beam splitter 21 and incident on the photodetector 24 and recorded on the recording surface of the disk-shaped recording medium 100 is separated as a polarization component. The return light is further incident on the condenser lens 25 and the multi-lens 26 in this order, and at this time, the recording information component of the disc-shaped recording medium 100, the focusing information component of the objective lens 9a, and the tracking information component of each divided beam are separated. It is to or coupled. The return light is incident on each light receiving surface of the photodiode 27 for each information component and is photoelectrically converted. Based on each information component, a control signal is sent to the biaxial actuator 9 and signal processing is performed.
0 reproduction or the like of the recorded information signals is made to.

When the optical pickup 7 is driven as described above, various electronic components serving as heat sources generate heat. In particular, the amount of heat generated by the semiconductor laser 17 from which laser light is emitted and the driving IC chip 16 is large.

The heat generated in the semiconductor laser 17 is mainly generated by the moving base 8 as a conductor and the second bearing 1.
It is transmitted to the guide shaft 6 via 1 and 11, and is discharged to the outside. On the other hand, heat generated in the driving IC chip 16 is mainly transmitted to the guide shaft 5 via the supported member 13 and the third bearing portion 13a, which are conductors, and is released to the outside.

At this time, as described above, the supported piece 10
Since the sliding members 12 and 12 made of an insulator are attached to the a and 10a and are in point contact with the guide shaft 5, between the movable base 8 and the guide shaft 5, the first bearing portion 10 is provided. Few heat is transmitted. Further, since the supported member 13 is supported by the moving base 8 via the elastic members 14 and 14 made of an insulator, the moving base 8 and the supported member 1 are supported.
Almost no heat is transmitted between the three.

As described above, in the disk drive device 1, the first heat-dissipating heat is transmitted from the movable base 8 to the guide shaft 6 via the second bearings 11, 11.
And the third bearing portion 13a from the supported member 13
And a second heat radiating path having a high heat radiating property through which heat is transmitted to the guide shaft 5 through the fins. Appropriate functions of the components can be ensured and the life of these electronic components can be extended.

Further, since two heat radiating paths having high heat radiating properties are secured, the amount of heat radiated from the surface of the moving base 8 is reduced, and an excessive rise in temperature inside the outer casing 2 of the disk drive device 1 is prevented. be able to.

In the disk drive 1, the supported member 13 is moved by the movable base 8 via the elastic members 14 and 14.
When the optical pickup 7 is moved in the radial direction of the disk-shaped recording medium 100, the supported member 13 follows the variation (dimension error) in the distance between the guide shafts 5 and 6 when the optical pickup 7 is moved in the radial direction. 8 is moved in the direction of coming and going.

Accordingly, the movement of the optical pickup 7 is not hindered, and the operation reliability of the optical pickup 7 can be ensured.

The driving IC chip 16 serving as a large heat source is mounted on the protrusion 15a of the flexible printed wiring board 15 mounted on the supported member 13, and the elastic members 14, 14 are formed of an insulator. Therefore, heat generated from the driving IC chip 16 is hardly transmitted to the moving base 8 and the semiconductor laser 17 is driven by the driving IC chip 16.
The heat generated by the C chip 16 does not affect the semiconductor chip 17 and the semiconductor laser 17 can be prevented from overheating.

Further, sliding members 12, 12 made of an insulator are provided on the first bearing 10, and the first bearing 10 is supported on the guide shaft 5 via the sliding members 12, 12. Therefore, heat generated from the driving IC chip 16 and transmitted to the guide shaft 5 is hardly transmitted to the moving base 8 via the first bearing portion 10, so that the semiconductor laser 17 can be further prevented from overheating. it can.

Next, an example in which heat generated from the semiconductor laser 17 attached to the movable base 8 is transmitted to the guide shaft 5 via the supported member 13 will be described (see FIGS. 6 and 7).

The semiconductor laser 17 is mounted on the movable base 8 on the side of the supported member 13. The semiconductor laser 17 is held by a laser holder 28, and the laser holder 28 is mounted on the moving base 8 by mounting screws 29, 29.

One end of an elastic sheet 30 made of a conductor is interposed between the laser holder 29 and the mounting surface of the movable base 8, and the other end of the elastic sheet 30 is attached to the supported member 13. ing.

The supported member 13 is an elastic member 3 made of a conductor.
It is supported by the moving base 8 via 1, 31.

The first bearing portion 10 of the movable base 8 is not provided with sliding members 12 made of an insulator.

The flexible printed wiring board 15 is not provided with a protrusion 15a protruding toward the supported member 13, and the driving IC chip 16 is moved, for example, toward the guide shaft 6 side of the flexible printed wiring board 15. It is mounted in the position where it was.

The heat generated in the semiconductor laser 17 is mainly due to the elastic sheet 30 as a conductor and the supported member 1.
The light is discharged from the guide shaft 5 to the outside via 3. on the other hand,
The heat generated in the driving IC chip 16 is mainly radiated from the guide shaft 6 to the outside via the moving base 8 and the second bearings 11, 11.

[0048] As described above, the heat generated in the semiconductor laser 17, primarily by way of the elastic sheet 30 and the support member 13 is a conductor released from the guide shaft 5 to the outside, the drive IC chip 16 The generated heat is radiated to the outside from the guide shaft 6 mainly through the moving base 8 and the second bearings 11, 11, so that sufficient heat is radiated by two heat radiation paths having high heat radiation. Thus, the heat radiation efficiency can be improved.

When the heat generated in the semiconductor laser 17 is released through the elastic sheet 30 as a conductor as described above, the moving base 8 is formed of a material having a low thermal conductivity, for example, a resin material. May be. If the moving base 8 is formed of a resin material, an inexpensive material can be used, so that the manufacturing cost of the disk drive device 1 can be reduced.

Next, an example in which a flexible printed wiring board 15 is used to connect the supported member 13 and the moving base 8 will be described (see FIGS. 8 to 10).

The supported member 13 is not connected via the elastic members 14 and 14.

At one end of the flexible printed wiring board 15, there is provided a protrusion 15a protruding toward the supported member 13, and between the movable base 8 and the supported member 13 of the protrusion 15a. Is formed as a slack portion 15b having a slack.

The movable base 8 is formed with a relief notch 8a at a position below one end of the slack portion 15b.

The supported member 13 has a relief notch 13b in a portion located below the other end of the slack portion 15b.

As described above, the flexible printed wiring board 1
By providing the slack portion 15b on the protrusion 15a of the zero, the optical pickup 7 follows the fluctuation (dimension error) of the distance between the guide shafts 5 and 6 when the optical pickup 7 is moved in the radial direction of the disk-shaped recording medium 100. The loosened portion 15b is expanded and contracted, and the supported member 13 is rotated in the direction around the guide shaft 5 (the θ direction shown in FIG. 8).

At this time, it is supposed that the slack portion 15b is displaced in the vertical direction as the slack portion 15b expands and contracts.
As described above, the escape notch 8a is formed in the movable base 8 at a portion located below one end of the slack portion 15b, and the supported member 13 is formed below the other end of the slack portion 15b. Since the escape notch 13b is formed in the located portion, interference between the slack portion 15b, the moving base 8, and the supported member 13 is avoided.

As described above, the slack portion 15b is provided on the protrusion 15a of the flexible printed wiring
If the supported member 13 is supported, the movement of the optical pickup 7 is not hindered, and the reliability of the operation of the optical pickup 7 can be ensured. In addition, it is not necessary to use the elastic members 14 and 14 to support the supported member 13 on the movable base 8, and accordingly, the manufacturing cost can be reduced by reducing the number of parts.

The specific shapes and structures of the respective parts shown in the above-described embodiments are merely examples of the embodiment of the present invention, and the technical features of the present invention are not limited thereto. The scope should not be construed as limiting.

[0059]

As is apparent from the above description, the optical pickup of the present invention has a moving base made of a conductor, a two-axis actuator supported on the moving base, and various electronic components serving as heat sources. with an optical pickup which moves by being guided by the pair of guide shafts made of a conductor in the radial direction of the disc-shaped recording medium mounted on the disc table, it is in point contact with the one of the guide shaft slidably in the moving base A first bearing portion supported and a second bearing portion slidably supported in surface contact with the other guide shaft, and supported by a moving base and in surface contact with the one guide shaft; A supported member made of a conductor having a third bearing portion is provided.

Accordingly, a first heat radiation path having high heat radiation from which the heat is transmitted from the movable base to the other guide shaft via the second bearing portion, and from the supported member via the third bearing portion. In addition, since a second heat-dissipating path with high heat-dissipation property to transfer heat to one guide shaft is secured, sufficient heat-dissipation is achieved, heat-dissipation efficiency is improved, and various electronic components serving as heat sources Functions can be ensured, and the life of these various electronic components can be extended.

Further, since two heat radiation paths having high heat radiation properties are secured, the amount of heat radiation from the surface of the moving base is reduced,
It is possible to prevent an excessive rise in temperature inside the outer casing of the device provided with the optical pickup.

According to the second aspect of the present invention, since the supported member is supported by the moving base via the elastic member, the pair of optical pickups is moved when the optical pickup is moved in the radial direction of the disk-shaped recording medium. The supported member is moved in the direction of moving away from the moving base following the fluctuation (dimension error) of the distance between the guide shafts, so that the moving operation of the optical pickup is not hindered and the operation reliability of the optical pickup is improved. Can be secured.

According to the third aspect of the present invention, since at least one heat source is disposed on the supported member and the elastic member is formed of an insulator, heat generated from the heat source disposed on the supported member is provided. Is hardly transmitted to the moving base, the heat generated from the heat source disposed on the supported member does not affect the heat source disposed on the moving base, and overheating of the heat source disposed on the moving base can be prevented.

In the invention described in claim 4, a sliding member made of an insulator is provided on the first bearing portion, and the first bearing portion is supported on the guide shaft via the sliding member. As a result, heat generated from the heat source disposed on the supported member and transmitted to one of the guide shafts is hardly transmitted to the moving base via the first bearing portion. Further overheating can be prevented.

The disk drive of the present invention comprises a disk table on which a disk-shaped recording medium is mounted and rotated, a moving base made of a conductor, a two-axis actuator supported on the moving base, and various heat sources. A disk drive having electronic components and moving in a radial direction of a disk-shaped recording medium mounted on a disk table, and a pair of guide shafts formed of conductors for guiding the optical pickup when the optical pickup is moved; A first bearing portion slidably supported by the movable base in point contact with the one guide shaft and a second bearing slidably supported in surface contact with the other guide shaft. And a supported member comprising a conductor having a third bearing portion supported by the moving base and in surface contact with one of the guide shafts. And wherein the digit.

Therefore, the first heat radiation path having high heat radiation from which the heat is transmitted from the moving base to the other guide shaft via the second bearing part, and the supported member via the third bearing part. In addition, since a second heat-dissipating path with high heat-dissipation property to transfer heat to one guide shaft is secured, sufficient heat-dissipation is achieved, heat-dissipation efficiency is improved, and various electronic components serving as heat sources Functions can be ensured, and the life of these various electronic components can be extended.

Further, since two heat radiation paths having high heat radiation properties are secured, the amount of heat radiation from the surface of the moving base is reduced,
Excessive temperature rise inside the outer casing of the disk drive device can be prevented.

In the invention described in claim 6, since the supported member is supported by the moving base via the elastic member, the pair of optical pickups is moved when the optical pickup is moved in the radial direction of the disk-shaped recording medium. The supported member is moved in the direction of moving away from the moving base following the fluctuation (dimension error) of the distance between the guide shafts, so that the moving operation of the optical pickup is not hindered and the operation reliability of the optical pickup is improved. Can be secured.

According to the seventh aspect of the present invention, at least one heat source is disposed on the supported member and the elastic member is formed of an insulator, so that the heat generated from the heat source disposed on the supported member is provided. Is hardly transmitted to the moving base, the heat generated from the heat source disposed on the supported member does not affect the heat source disposed on the moving base, and overheating of the heat source disposed on the moving base can be prevented.

In the invention described in claim 8, a sliding member made of an insulator is provided on the first bearing portion, and the first bearing portion is supported on the guide shaft via the sliding member. As a result, heat generated from the heat source disposed on the supported member and transmitted to one of the guide shafts is hardly transmitted to the moving base via the first bearing portion. Further overheating can be prevented.

[Brief description of the drawings]

FIG. 1 shows an embodiment of the present invention together with FIG. 2 to FIG. 10, and FIG. 1 is a schematic perspective view of a disk drive device.

FIG. 2 is an enlarged side view showing a main part with a partial cross section.

FIG. 3 is an enlarged plan view showing a main part.

FIG. 4 is an enlarged side view showing a state where a main part is partly in cross section and viewed from a side opposite to FIG. 2;

FIG. 5 is an enlarged perspective view illustrating a configuration of an optical element provided in the optical pickup.

6 shows an example in which heat generated in the semiconductor laser is released through the elastic sheet and the supported member together with FIG. 7, and FIG. 6 is an enlarged side view showing a part of the cross section.

FIG. 7 is an enlarged plan view showing a part in section.

8 shows an example in which a supported member is connected to a moving base via a flexible printed wiring board together with FIGS. 9 and 10, and FIG. 8 is an enlarged side view showing a part of the cross section.

FIG. 9 is an enlarged plan view.

FIG. 10 is an enlarged side view showing a part of the cross section as viewed from the opposite side to FIG. 8;

FIG. 11 is a schematic enlarged perspective view showing a part of a configuration of an optical pickup in a conventional disk drive device, with a part cut away.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Disk drive device, 4 ... Disk table, 5
... guide shaft, 6 ... guide shaft, 7 ... optical pickup, 8
... Moving base, 9 ... Two-axis actuator, 10 ... First
Bearing part, 11 ... second bearing part, 12 ... sliding member, 13
... Supported member, 13a ... Third bearing part, 14 ... Elastic member, 16 ... Drive IC chip (heat source), 17 ... Semiconductor laser (heat source), 31 ... Elastic member, 100 ... Disk recording medium

Claims (8)

[Claims] 1. A moving base comprising a conductor, a two-axis actuator supported on the moving base, and various electronic components serving as a heat source, and from a conductor in a radial direction of a disk-shaped recording medium mounted on a disk table. An optical pickup that is guided and moved by a pair of guide shafts, the first base being slidably supported by a moving base in point contact with one of the guide shafts, and being in surface contact with the other guide shaft. And a second bearing portion slidably supported by the movable base, and a supported member comprising a conductor having a third bearing portion supported by the moving base and in surface contact with the one guide shaft is provided. Optical pickup featured. 2. The optical pickup according to claim 1, wherein the supported member is supported by a movable base via an elastic member. 3. The optical pickup according to claim 2, wherein at least one heat source is disposed on the supported member, and the elastic member is formed of an insulator. 4. A sliding member made of an insulator is provided on said first bearing portion, and said first bearing portion is supported on a guide shaft via said sliding member. Item 4. The optical pickup according to item 3. 5. A disk having a disk table on which a disk-shaped recording medium is mounted and rotated, a moving base made of a conductor, a two-axis actuator supported on the moving base, and various electronic components serving as a heat source. A disk drive device comprising: an optical pickup that moves in a radial direction of a disk-shaped recording medium mounted on a table; and a pair of guide shafts formed of a conductor that guides the optical pickup when the optical pickup moves. A first bearing portion slidably supported by point contact with the one guide shaft and a second bearing portion slidably supported by surface contact with the other guide shaft. A disk drive provided with a supported member comprising a conductor having a third bearing portion supported by a base and brought into surface contact with one of the guide shafts. Breakfast apparatus. 6. The disk drive according to claim 5, wherein the supported member is supported by a movable base via an elastic member. 7. The disk drive device according to claim 6, wherein at least one heat source is arranged on the supported member, and the elastic member is formed of an insulator. 8. The apparatus according to claim 1, wherein a sliding member made of an insulator is provided on said first bearing portion, and said first bearing portion is supported on a guide shaft via said sliding member. Item 8. The disk drive device according to item 7.