JP2001202644A - Driving device for information recording medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a driving device for an information recording medium which can realize reduction in space, cost reduction, and low power consumption. SOLUTION: The driving device has a skew adjustment part 150 for moving an optical part 1 in the inclined direction according to the inclination state of a disk-like information recording medium, when the disk-like information recording medium 90 is mounted. The skew adjustment part 150 is equipped with a rotating body 14 which has a cam groove 15 holding a supporting member for supporting the optical recording/reproducing part 1, a moving body 170 engaging mechanically to rotate the rotating body 14, and a shape memory alloy member 200 for movement operation which moves the optical recording/ reproducing part 1 according to the inclination state of the disk-like information recording medium in the inclined direction by linearly moving the moving body 170 by power-on, rotating the rotating body 14, and guiding a supporting member 8a for supporting the optical part 1 by the cam groove 15.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a drive device for an information recording medium for recording or reproducing information by rotating a disk-shaped information recording medium.

[0002]

2. Description of the Related Art Recently, as recording media for various data and programs used for personal computers and the like, disk-shaped disks such as a CD-ROM (read only memory using a compact disk) and an MO (magneto-optical) disk. An information recording medium (hereinafter, referred to as a “disk”) is known. Such a disk is rotated at a predetermined speed after being loaded into the disk drive device, and then the optical pickup reads data or the like recorded on the signal surface.

By the way, when reading data or the like recorded on a disk, a disk drive capable of rotating the disk at a speed higher than a standard speed (1 × speed) for the purpose of improving the reading efficiency. Devices are known. In such a disk drive device, the rotational speed of the disk is reduced to a standard speed (200 to 5).
For example, 4 × speed, 6 × speed, 8
The data reading efficiency is improved by increasing the transfer rate of the reproduced data by using a high-speed rotation such as a double speed,..., 32 times.

[0004]

In this type of disk drive, the optical pickup can be moved in the tilt direction in order to perform so-called skew correction according to the tilt state of the mounted disk. ing. Japanese Patent Application Laid-Open No. H11-328837 discloses a disk drive device of this type, which is provided with a skew motor and a plurality of gears in order to perform skew correction of an optical pickup. The skew motor used is a large columnar motor having a so-called rotor and stator, and it is difficult to reduce the size, cost, and power consumption of the drive device. Accordingly, an object of the present invention is to provide a drive device for an information recording medium that can solve the above-mentioned problems and can achieve a reduction in space, cost, and power consumption.

[0005]

According to a first aspect of the present invention, there is provided an information recording medium drive device for recording or reproducing information by rotating a disk-shaped information recording medium. An optical unit that records information on a recording medium or reproduces information on the disc-shaped information recording medium; and an inclination of the disc-shaped information recording medium when the disc-shaped information recording medium is mounted. And a skew adjustment unit for moving the optical unit in a direction in which the optical unit is inclined according to a state.
A rotating body having a cam groove holding a support member for supporting the optical unit, and a moving body that is mechanically engaged to rotate the rotating body, by energizing,
By moving the moving body linearly and rotating the rotating body, a supporting member for supporting the optical unit is guided by the cam groove, and the optical member is guided according to the tilt state of the disc-shaped information recording medium. And a shape memory alloy member for moving operation for moving the section in a direction of inclination.

According to the first aspect, the optical unit records information on a disk-shaped information recording medium and reproduces information on the disk-shaped information recording medium. The skew adjustment unit moves the optical unit in a direction in which the optical unit is tilted in accordance with the tilt state of the disk-shaped information recording medium when the disk-shaped information recording medium is mounted. The rotating body of the skew adjustment unit has a cam groove holding a support member for supporting the optical unit. The moving body is mechanically engaged to rotate the rotating body. The shape memory alloy member for the moving operation, when energized, linearly moves the moving body and rotates the rotating body, so that the support member for supporting the optical unit is guided by the cam groove and the disc-shaped information is formed. The optical unit is moved in a direction in which the optical unit is inclined according to the state of inclination of the recording medium. This eliminates the need for a large motor, which was conventionally required, and uses a very small shape memory alloy member as compared to the motor to move the support member for supporting the optical unit, thereby allowing the optical unit to move. Skew adjustment can be performed. By using such a shape memory alloy member, it is possible to reduce the space, cost, and power consumption as compared with using a conventional motor.

According to a second aspect of the present invention, in the information recording medium drive device according to the first aspect, the supporting member for supporting the optical section is formed by connecting the optical section to the disc-shaped information recording medium in a radial direction. This is the feed axis when sending to. In claim 2, the support member for supporting the optical unit is a feed shaft for feeding the optical unit in the radial direction of the disc-shaped information recording medium.

According to a third aspect of the present invention, in the information recording medium drive device according to the first aspect, the rotating body has a gear, the moving body has a rack, and the gear and the rack mesh with each other. I have. According to the third aspect, the gear of the rotating body mechanically meshes with the rack of the moving body, so that the linear movement of the moving body can be easily converted into the rotating movement of the rotating body.

According to a fourth aspect of the present invention, in the information recording medium drive device according to the first aspect, the rotating body is urged in a first rotational direction by an urging member with respect to a fixed portion. The rotating body rotates in a second rotation direction opposite to the first rotation direction against the urging force of the urging member with the movement of the moving body. In claim 4, the rotating body is normally urged by the urging member in the first rotation direction. However, the skew of the optical unit is adjusted by rotating the rotating body in the second rotation direction against the urging force of the urging member with the movement of the moving body.

According to a fifth aspect of the present invention, in the drive device for an information recording medium according to the first aspect, when the rotation of the rotating body is prevented, the rotating body is engaged with the moving body. It has a lock operation unit for releasing the engagement. According to the fifth aspect, the lock operation section engages with the moving body, thereby preventing rotation of the rotating body and positioning the feed shaft after the skew adjustment.

According to a sixth aspect of the present invention, in the information recording medium drive device according to the fifth aspect, the lock operation section includes a lock member for engaging a portion of the moving body,
A shape memory alloy member for locking different from the shape memory alloy member for moving operation, wherein the shape memory alloy member for locking operation for retracting the lock member from a portion of the moving body by energizing Have. According to the sixth aspect, the lock member of the lock operation unit engages with the part of the moving body. The shape memory alloy member for locking is configured to retreat the lock member from a portion of the moving body when energized. Thus, the locked state of the moving body can be released, and the skew adjustment of the optical unit can be performed again.

According to a seventh aspect of the present invention, in the information recording medium drive device according to the sixth aspect, a plurality of the parts are formed at equal intervals on the moving body.

According to an eighth aspect of the present invention, in the information recording medium drive device according to the seventh aspect, the portion of the moving body is a concave portion or a convex portion.

According to a ninth aspect of the present invention, in the information recording medium drive according to the fourth aspect, one end of the shape memory alloy member for the moving operation is fixed by press-fitting using a boss in the moving body. The other end of the shape memory alloy member for the moving operation is fixed by press fitting using a boss on the fixing portion side. In the ninth aspect, one end of the shape memory alloy member for the moving operation is fixed to the moving body using a boss. Similarly, the other end of the shape memory alloy member for the moving operation is fixed to the fixed portion using a boss. Since the shape memory alloy member is strong in the compressed state by press-fitting, there is no problem even if it is simply fixed by press-fitting.

[0015]

Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings. Note that the embodiments described below are preferred specific examples of the present invention,
Although various technically preferable limits are given, the scope of the present invention is not limited to these modes unless otherwise specified in the following description.

FIG. 1 shows a preferred embodiment of a drive device for an information recording medium according to the present invention. This drive device is a device for driving an optical disk which is an example of a disk-shaped information recording medium. Drive device 100 of FIG.
For example, a disc 90 such as an optical disc loaded in a CD-DA (Compact Disc Digit)
AL-AUDIO), CD-type discs such as CD-ROM, and DVD (DIGITAL VERSATIL)
E DISC / DIGITAL VIDEO DIS
A disk called C) is conceivable. Of course, the present invention can be applied to a drive device corresponding to another type of disk.

The disk 90 shown in FIG.
And a constant linear velocity (CLV) or a constant angular velocity (CA) by the spindle motor 6 during the reproducing operation.
V). Then, data recorded in a pit form on the disk 90 is read by the optical pickup 1 as an optical unit.

The laser light from the laser diode 4 in the optical pickup 1 is applied to the recording surface of the disk 90 from the objective lens 2 via an optical system (not shown).
The objective lens 2 is held by a biaxial mechanism 3 so as to be movable in a tracking direction and a focus direction. Tracking and focus control of laser light are performed by the operation of the biaxial mechanism 3.

The reflected light information of the laser light from the disk 90 is detected by the detector 5 from the objective lens 2 via an optical system (not shown), and the detector 5 supplies an electric signal corresponding to the amount of received light to the RF amplifier 21.

The RF amplifier 21 generates a necessary signal based on a signal from the detector 5. For example, it generates an RF signal as reproduction data, a focus error signal FE for servo control, a tracking error signal TE, and the like.

Various signals generated by the RF amplifier 21 are:
It is supplied to the binarization circuit 25 and the servo processor 31.
The reproduced RF signal from the RF amplifier 21 is converted to a binarization circuit 25.
Supplied to The focus error signal FE, the tracking error signal TE, and the like are supplied to the servo processor 31.

The reproduced RF signal obtained by the RF amplifier 21 is binarized by a binarization circuit 25, so that, for example, EFM
The signal is supplied to the decoder 26 as a signal (8-14 modulated signal; when the disk 90 is a CD disk) or an EFM + signal (8-16 modulated signal; when the disk 90 is a DVD disk). Decoder 26
Performs EFM demodulation, etc., and if necessary,
The information read from the disc 90 by performing OM decoding or the like is reproduced.

The servo processor 31 includes an RF amplifier 21
From the focus error signal FE, the tracking error signal TE, and the spindle error signal SPE from the decoder 26 or the system controller 30, various servo drive signals for focus, tracking, sled, and spindle are generated to execute the servo operation.

In response to the focus error signal FE and the tracking error signal TE, a focus drive signal and a tracking drive signal are generated, and the two-axis driver 18
To supply. The two-axis driver 18 drives the two-axis mechanism 3 in the optical pickup 1. Thereby, a tracking servo loop and a focus servo loop by the optical pickup 1, the RF amplifier 21, the servo processor 31, and the two-axis driver 18 are formed.

The servo processor 31 sends a spindle error signal SPE to the spindle motor driver 19.
Is supplied, and the CAV rotation or CLV rotation of the spindle motor 6 is executed.

The rotation speed of the spindle motor can be set to a high speed such as double speed, quadruple speed, and octuple speed when the normal speed is set to 1 × speed.

The FG 27 generates a frequency pulse (FG pulse) corresponding to the rotation speed of the spindle motor 6 and supplies it to the servo processor 31. For example, six FG pulses are generated for one rotation of the spindle motor 6.

The sled mechanism 8 shown in FIG. 1 indicates the parts such as the main shaft 8a, the sled motor 8b, the sled transmission gears 8c, 8d and 8e shown in FIG. By driving the sled motor 8b of the sled mechanism 8 of FIG. 2 according to the sled drive signal by the sled driver 17 of FIG. 1, the optical pickup 1 performs an appropriate sliding movement in the A direction.

The system controller 30 receives the movement information TKC from the thread sensor 10 and the optical pickup 1
The speed signal SLv of the optical pickup 1 is generated and supplied to the servo processor 31. At the same time, rough position information of the optical pickup 1 obtained from the movement information TKC is supplied to the servo processor 31.

The servo processor 31 generates a thread error signal from the speed signal SLv from the system controller 30 and the tracking error signal TE from the RF amplifier 21 and the like. A drive signal is generated and supplied to the thread driver 17. The sled driver 17 drives the sled mechanism 8 according to the sled drive signal to control the feed of the optical pickup 1.

The laser diode 4 of the optical pickup 1 shown in FIG. The servo processor 31 generates a laser drive signal for performing laser emission of the optical pickup 1 at the time of reproduction or the like based on an instruction from the system controller 30, and supplies the laser drive signal to the laser driver 20.

Various operations such as servo and decoding as described above are controlled by a system controller 30 formed by a microcomputer. For example, operations such as playback start, end, and track access (seek)
This is realized by the system controller 30 controlling the operations of the servo processor 31 and the optical pickup 1.

Next, with reference to FIG. 2, the structure of a drive for reproducing a disk (so-called mechanical deck) of the information recording medium drive device 100 will be described. On the sub-chassis main body 11 of the mechanical deck, various mechanisms necessary for driving and reproducing the disc are provided. The loaded disk 90 is mounted on the turntable 7, and the disk 90 is rotated by the rotation of the turntable 7 by the spindle motor 6.

The optical pickup is provided with an optical system for irradiating the rotating disk 90 with laser light and extracting information from the reflected light, and a laser light source. In the optical pickup 1, the objective lens 2 serves as an output end of the laser beam, and faces the disk 90 as shown in the figure.

The optical pickup 1 is slidable in the disk radial direction by the sled mechanism shown in FIG.
Therefore, a main shaft 8a and a sub shaft 12 are provided on both sides of the optical pickup 1. The main shaft 8a passes through the holder portion 8g of the optical pickup 1 and the sub shaft 12 passes through the holder portion 12g on the opposite side.
a can be moved in the shaft direction while being supported by the sub-shaft 12.

As a mechanism for moving the optical pickup 1 on the shaft, a thread motor 8b and thread transmission gears 8c, 8d, 8e are provided, and a rack gear 8f is mounted near the holder 8g of the optical pickup 1. ing. When the thread motor 8b is rotationally driven, its rotational force is transmitted to the thread transmission gears 8c, 8d,
8e. The thread transmission gear 8e is a rack gear 8f
The transmitted rotational force moves the optical pickup 1 in the shaft direction. Therefore, the optical pickup 1 is moved in the shaft direction, that is, in the disk radial direction by the forward / reverse rotation of the sled motor 8b.

The optical pickup 1 is movable in the tilt direction so as to perform so-called skew correction according to the tilt state of the loaded disk. Therefore, one end of the main shaft 8a is held by the sub-chassis body 11 by the holding portion 8h, and the other end is in a cam groove 15 formed in the skew gear 14.

In FIG. 2, a skew adjustment unit 150 is mounted on the drive device 100. The skew adjustment unit 150 adjusts the skew of the optical pickup 1 as an optical reproducing unit in the Z direction by moving the main shaft 8a as a feed shaft and a support member in the Z direction. Thereby, the optical pickup 1 is moved around the sub-shaft 12 in the Z direction, which is the tilt direction, in accordance with the tilt state of the disk 90 loaded on the turntable 7 of the spindle motor 6 to perform the skew correction. It can be carried out.

The skew adjusting section 150 will be described in detail below. As shown in FIG. 3, the skew adjustment unit 150 roughly includes the rotating body 14, the moving body 170, the shape memory alloy member 200 for moving operation, and the like.
As shown in FIGS. 2 and 3, the skew adjusting unit 150
It is provided on the basis of the side plate 199 which is a fixing portion.
The side plate 199 is integrally fixed to the sub-chassis 11 in FIG. 2 and is provided upright on the rear side of the rotating body 14. The side plate 199 is preferably made of an electrical insulator such as plastic.

In FIGS. 3 and 5, the rotating body 14 is a disk, and is adapted to rotate about the central axis 14A in the first rotation direction R1 or the second rotation direction R2.
The rotating body 14 is desirably made of an insulating material such as plastic. The rotating body 14 has a cam groove 15. The cam groove 15 is formed so as to be eccentric about the center axis 14A. The end of the main shaft 8a is inserted into the cam groove 15. In addition, as shown in FIG. 1, the rotating body 14 is prevented from falling off by a retaining ring PG. Cam groove 1
The shape of 5 is a circular arc shape as shown in FIGS. The main shaft 8a has a central axis 14A in FIG.
When the rotating body 14 rotates in the first rotation direction R1 or the second rotation direction R2, the main shaft 8a
The eccentric state of the cam groove 15 causes the cam groove 15 to move up and down along the Z direction, that is, the radial direction of the rotating body 14.

A gear 14B is provided on the rear side of the rotating body 14 in FIG.
Has been fixed. As shown in FIG. 3 and FIG.
Is set smaller than the diameter of the rotating body 14. This gear 14B is preferably made of an electrical insulator such as plastic. The gear 14B and the rotating body 14 can be formed integrally, or the gear 14B and the rotating body 1 can be formed integrally.
4 can be molded separately and then integrated with an adhesive or the like. As shown in FIGS. 3 and 8, the rotating body 14 and the side plate 19
9, a torsion coil spring 260 as an urging member is set. One end 261 of the torsion coil spring 260 is pin 262 with respect to the rotating body 14 and the gear 14B.
Has been fixed through. However, the torsion coil spring 2
The other end 263 of the 60 is fixed to the side plate 199 via a pin 264. The torsion coil spring 260 normally urges the rotating body 14 and the gear 14B in the first rotation direction R1 in FIG.

Next, the moving body 170 and the shape memory alloy member 200 for moving operation in FIG. 3 will be described. Moving object 1
70 is preferably made of a conductor, for example. The moving body 170 is a plate-shaped member, and is arranged in parallel with the side plate 199 as shown in FIGS. 3 and 5, and the moving body 170 is moved along the guide 171 of FIG.
It is provided so as to be movable in two directions. Moving object 1
A rack 173 is provided above 70. The rack 173 is engaged with the gear 14B of the rotating body 14. On the lower side of the moving body 170, for example, a concave portion 1
74 are provided. The portions 174 are formed, for example, at equal intervals along the T1 direction. Site 17
4 are preferably formed at a pitch corresponding to the pitch at which the racks 173 are formed. A guide groove 176 is formed in an intermediate portion of the moving body 170 along the T1 direction. A large hole 177 is formed at one end of the guide groove 176. A boss 180 is provided at one end of the moving body 170.
Is provided. This boss 180 and the central boss 18
Between them, a shape memory alloy member 200 for moving operation is attached. FIG. 9 shows an example of a cross-sectional structure taken along line FF in FIG.

The boss 184 of FIG. 9 is directly fixed to the moving body 170. The boss 180 is screwed and fixed to the boss 184. One end 201 of the shape memory alloy member 200 is located between the bosses 180 and 184 in FIG.
It is fixed by press fitting as shown in FIG. The other end 202 of the shape memory alloy member 200 is connected to the boss 1 as shown in FIG.
Also between 81 and another boss 185 is fixed by press fitting. The boss 185 is the guide groove 1 of the moving body 170.
It just goes to 76. However, the shaft portion 181A of the boss 181 is screwed and fixed to the side plate 199.
Therefore, the bosses 181, 185 and the shape memory alloy member 200
Is fixed to the side plate 199 without moving its position. Another boss 187 also has a side plate 199
3, but passes through the guide groove 176 of the moving body 170 as shown in FIG.
70 is in electrical contact.

The bosses 180 and 185 in FIG. 9 are made of an electrical insulator such as plastic. On the other hand, the boss 184, the boss 181 and the boss 187 are made of a conductive material. As the conductive material, a metal or a resin coated with a metal can be used. As a result, from the energization control unit 200 in FIG. 3, for example, the shape memory alloy member 2 for operation is operated as shown in FIG.
00 can be energized. First, the energizing section 200
9 passes through the boss 181, the shape memory alloy member 200, the boss 184, and the moving body 170 in FIG.
Then, the process returns to the energization control unit 200 in FIG.

Thus, when the shape memory alloy member 200 for moving operation is energized, the shape memory alloy member 200 exerts a tensile force. The shape memory alloy member 200 is shown in FIG.
When the pulling force is exerted at
Move in the direction. An example of the movement is shown in FIG. As described above, when the moving body 170 moves in the T1 direction,
The rotating body 14 can rotate against the urging force of the torsion coil spring 260 along the second rotation direction R2.
Thereby, the main shaft 8a is lifted in the Z direction along the cam groove 15, so that the main shaft 8a
2, that is, skew correction in the Z direction of the optical pickup 1 in FIG. 2 can be performed. By changing the amount of energization from the energization control unit 200 to the shape memory alloy member 200 for the moving operation, the degree of the tensile force of the shape memory alloy member 200 can be adjusted, so that the second rotation direction R2 of the rotating body 14 can be adjusted. , The skew correction amount of the main shaft 8a in the Z direction can be adjusted.

Next, a boss 330 is provided on the side plate 199 as shown in FIG. The boss 330 fixes one end of the lock member 340. Lock member 340
Are mechanically engaged with the portion 174 of the moving body 170. The lock member 340 is formed by the shape memory alloy member 400 for locking operation along the direction E in the region 1.
74. One end of the shape memory alloy member 400 is fixed to the lock member 340, and the other end is fixed to the boss 350. The energization method for the shape memory alloy member 400 is as follows. The energization control unit 200 includes the boss 330 and the boss 35
0, and the shape memory alloy member 400
Is supplied with current through the bosses 350 and 330. When an electric current passes through the shape memory alloy member 400, a tensile force is exerted, so that the lock member 340 retreats from the portion 174 around the boss 330 along the direction E and becomes the state shown in FIG. The lock member 340 has a function of positioning and fixing the moving body 170 in the direction of T1 or T2 since the lock member 340 is engaged with the corresponding portion 174.

Shape memory alloy member 2 for moving operation described above
00 and the following shape memory alloy member 400 for lock operation can be employed. The shape memory alloy member 200 and the shape memory alloy member 400 exhibit superelasticity by being energized together and exhibit a function as a tension coil spring. The shape memory alloy member 200 and the shape memory alloy member 400 are made of, for example, Ti (titanium), Ni
It is an alloy member made of (nickel) and Cu (copper).
However, the present invention is not limited to this.
0,400 may be an alloy of Ni and Ti.

Next, an example of the operation of the skew adjusting unit 150 in the above-described information recording medium drive device 100 will be described. For example, in FIG. 3, an example will be described in which the skew correction of the main shaft 8a in the Z direction is performed by changing the state of the moving body 170, for example, to the state of the moving body 170 as shown in FIG. Moving object 1 in FIG.
The locking member 340 is engaged with the portion 174 of the 70, and in this state, the moving body 170 is fixed in the T1 direction and the T2 direction.

FIG. 11 shows the power supply control unit 200 shown in FIG.
Shows an example of a time chart in which a drive signal S1 is supplied to a shape memory alloy member 200 for a moving operation, and an energization control unit 200 supplies an unlock signal S2 to a shape memory alloy member 400 for a lock operation. I have. First, when the energization control unit 200 of FIG. 3 supplies a current that is the lock release signal S2 to the shape memory alloy member 400, the lock member 34
0 retreats from the part 174 along the E direction. Thus, the moving body 170 can move in the direction of T1 or T2.

Next, when the energization control unit 200 shown in FIG. 3 supplies a drive signal S1 shown in FIG. 11 to the shape memory alloy member 200 for the moving operation, the shape memory alloy member 200 exerts a pulling force to move. The body 170 moves in the T1 direction.
Accordingly, the rotating body 14 rotates against the biasing force of the torsion coil spring 260 along the second rotation direction R2.
Therefore, since the main shaft 8a is guided along the cam groove 15, the main shaft 8a rises in the Z direction so as to approach the central axis 14A.
The shape memory alloy member 200 exerts a tensile force in accordance with the magnitude of the current which is the drive signal S1, so that the moving amount of the moving body 170 in the T1 direction is
It may be adjusted according to the skew correction amount in the direction.
Thereafter, by turning off the lock release signal S2 shown in FIG. 11, the tensile force of the shape memory alloy member 400 shown in FIG. 3 is released, and the lock member 340 fits into the corresponding position 174 as shown in FIG. Put in. With this, moving body 1
The movement of the rotating body 14 in the T1 direction or the T2 direction can be stopped, and the rotation of the rotating body 14 can also be prevented.

As described above, according to the present invention, since the skew of the main shaft 8a can be adjusted by using the shape memory alloy member, it is possible to use a conventionally used large electromagnetic columnar motor. In comparison, drive device 1
00 can be significantly reduced in size, and cost and power consumption can be reduced. From this, it is possible to secure the thinness and high reliability of the drive device 100.

Each of the bosses in FIGS. 3 and 9 is press-fitted, caulked or adhered to the moving body 170 or the side plate 199.
Can be fixed. Also, the shape memory alloy member 20
The energization amount to 0,400 in FIG. 11 can be increased stepwise in one step, two steps, three steps as shown in FIG. , The angle of the skew correction can be obtained, and locking is performed by the lock member 340 at that position. Conversely, only the shape memory alloy member 400 is energized, and the moving body 170 is moved in the T2 direction by the torsion coil spring 260 by gradually increasing the number of steps to one, two, and three. I can earn. In order to shorten the access time, as shown in FIG.
A large amount of current may flow only at the rise of the first stage.

The present invention is not limited to the above embodiment. In the above example, the disc is a read-only disc such as a CD-ROM. However, when a disk that can perform both recording and reproduction is used as the disk, an optical pickup for recording and reproduction is used. In this case, the optical pickup has an element for recording information on the disk, for example, a laser light source for recording or a magneto-optical recording unit for performing magneto-optical recording, and the optical pickup is an optical recording / reproducing unit. is there.

[0054]

As described above, according to the present invention,
Space, cost, and power consumption can be reduced.

[Brief description of the drawings]

FIG. 1 is a system diagram of a drive device for an information recording medium according to the present invention.

FIG. 2 is a perspective view showing a mechanical part of the drive device.

FIG. 3 shows a skew adjustment unit of the drive device;
The figure seen from the E direction in FIG.

FIG. 4 is a diagram illustrating an example after adjustment by a skew adjustment unit.

FIG. 5 is a perspective view showing the structure of a skew adjustment unit.

FIG. 6 is a front view showing a shape example of a rotating body.

FIG. 7 is a perspective view showing an example of the shape of a rotating body.

FIG. 8 is a perspective view showing a torsion coil spring between a rotating body and a side plate.

FIG. 9 is a diagram showing an example of a cross-sectional structure taken along line FF of FIG. 3;

FIG. 10 is an enlarged view showing a state in which the shape memory alloy member is attached to the boss.

FIG. 11 is a time chart showing an example of energizing a shape memory alloy member.

FIG. 12 is a time chart showing another example of energization.

[Explanation of symbols]

1 optical pickup (optical part), 8a main shaft (supporting member), 14 rotating body, 15
Cam groove, 100 drive device, 150 skew adjustment unit, 170 moving body, 199 side plate (fixed portion), 200 shape memory alloy member for moving operation, 260 ... Torsion coil springs (biasing members), 40
0: Shape memory alloy member for lock operation

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Takashi Igarashi 6-35 Kita Shinagawa, Shinagawa-ku, Tokyo F-term within Sony Corporation (reference) 5D118 AA08 AA13 BA01 CD04 FB00

Claims (9)

[Claims] An information recording medium drive device for recording or reproducing information by rotating a disk-shaped information recording medium, wherein the information is recorded on the disk-shaped information recording medium, An optical unit that reproduces information on a disc-shaped information recording medium; and a direction in which the optical unit is inclined in accordance with an inclination state of the disc-shaped information recording medium when the disc-shaped information recording medium is mounted. A skew adjusting unit for moving the rotator, the skew adjusting unit comprising: a rotating body having a cam groove holding a support member for supporting the optical unit; and A moving member that is mechanically engaged with the moving member, by energizing, moving the moving body linearly and rotating the rotating body, thereby forming a supporting member for supporting the optical unit; A shape memory alloy member for a moving operation for guiding the optical section in a direction in which the optical section is tilted in accordance with a tilted state of the disc-shaped information recording medium guided by a cam groove. Drive device. 2. The information recording medium drive according to claim 1, wherein the support member for supporting the optical section is a feed shaft for feeding the optical section in a radial direction of the disc-shaped information recording medium. apparatus. 3. The information recording medium drive device according to claim 1, wherein the rotating body has a gear, the moving body has a rack, and the gear and the rack mesh with each other. 4. The rotating body is urged by a biasing member in a first rotation direction with respect to a fixed portion.
2. The information recording medium drive device according to claim 1, wherein the moving member rotates in a second rotation direction opposite to the first rotation direction against a biasing force of the biasing member. 5. The information recording medium according to claim 1, further comprising: a lock operation section that engages with the moving body when the rotation of the rotating body is prevented, and releases the engagement when the rotating body rotates. Drive device. 6. The lock operation section is a lock member for engaging with a part of the moving body, and a lock shape memory member different from the shape memory alloy member for the move operation, and is configured to be energized. The information recording medium drive device according to claim 5, further comprising: a shape memory alloy member for the lock operation for retracting the lock member from a portion of the moving body. 7. The information recording medium drive device according to claim 6, wherein a plurality of the portions are formed at equal intervals on the moving body. 8. The drive device for an information recording medium according to claim 7, wherein the portion of the moving body is a concave portion or a convex portion. 9. One end of the shape memory alloy member for the moving operation is fixed by press-fitting using a boss in the moving body, and the other end of the shape memory alloy member for the moving operation is the fixing portion. The drive device for an information recording medium according to claim 4, wherein the side is fixed by press-fitting using a boss.