JPH0554564A - Optical block transfer mechanism - Google Patents

Abstract

(57) [Summary] [Objective] In an optical disk device, a high-speed seek operation of the optical block is facilitated, and the positioning operation of the optical block to a specific track on the optical disk is quickly and qualified. Achieve thinning. [Structure] The four linear motors 7, 8, 9 and 10 arranged symmetrically with respect to the center of gravity of the optical block 11 cause the optical block 11 having an optical head to extend in the radial direction across the inner and outer circumferences of the optical disc 3. It was configured to be transferred.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical block transfer mechanism having an optical head for writing and / or reading information signals to and from a disk-shaped recording medium such as an optical disk or a magneto-optical disk.

[0002]

2. Description of the Related Art Conventionally, an optical disc recording and / or reproducing apparatus for writing and / or reading an information signal to and from a disc-shaped recording medium such as an optical disc or a magneto-optical disc has been proposed. As shown in FIG. 3, such an optical disc recording and / or reproducing apparatus has a chassis 102 supported in an outer casing 101, and holds an optical disc 103 on the chassis 102 while rotating the optical disc 103. ..

The rotation operation of the optical disk 103 is performed by the spindle motor 103 mounted on the chassis 102,
The optical disk 103 is mounted on the drive shaft of the spindle motor 103, and the optical disk 103 is mounted on the disk table 104.

In the radial direction of the optical disc 103, there is provided an optical block 105 having an optical head which is radially transported by the pair of linear motors 106 and 107 over the inner and outer circumferences of the optical disc 103.

Optical block 10 having the above optical head
5 includes a light source such as a semiconductor laser, a predetermined optical device including an objective lens 108 that guides a light beam emitted from the light source, a photodetector, and the like. And
By irradiating the optical disc with the light flux and detecting the reflected light from the optical disc, writing and / or reading of an information signal with respect to the optical disc is performed.

Two linear motors 106 and 107 are also provided.
Are each composed of a fixed member 109 and a moving member 110. The fixing member 109 of the linear motor is composed of a magnet or the like that forms a magnetic path together with upper and lower magnetic yokes. The moving member 110 is the coil 1
A bobbin 112 around which 11 is wound is provided. The bobbin 112 is connected to the bobbin 112 at two positions in the transfer direction of the optical block 105 via screw members and the coil 1
An energizing pin for 11 is provided.

The moving member 11 of the linear motor
Reference numeral 0 denotes two guide shafts 11 arranged to face each other in the radial direction of the optical disc 103 on the chassis 102.
3 and 114 are penetrated and supported to guide the optical block 105 toward the optical disc 103.

Therefore, in the transfer mechanism having the above structure, the coils 111 of the pair of linear motors 106 and 17 are arranged.
The bobbin 112, which is a moving part, is driven by simultaneously energizing the optical block 105, and the optical block 105 connected to the moving member 110 slides on the two guide shafts 113 and 114 to extend over the inner and outer circumferences of the optical disc 103. It is possible to read and write and / or write the information signal by transferring the information signal in the radial direction.

[0009]

By the way, in the above-mentioned optical block transfer mechanism, generally, the weight of the optical block including the optical head for writing and / or reading the information signal is relatively heavy. Therefore, with two linear motors for driving the optical block as in the conventional example, it is difficult to realize high-speed movement of the optical disk in the radial direction of the optical disk (so-called seek operation of the optical block). is there. In particular, when miniaturization and thinning are required, there is a limit to improving the performance of the linear motor, which is extremely difficult.

Therefore, in the conventional transfer mechanism, it is not impossible to increase the number of turns of the coil with respect to the bobbin or to increase the magnetic force of the magnet. However, increasing the number of turns of the coil increases the mass of the bobbin as the moving part of the linear motor, hinders quick drive movement operation and stop, and increasing the magnetic force of the magnet increases the There is a problem that the leakage magnetic flux from the magnet increases and the leakage magnetic flux may adversely affect the constituent elements of the optical head held by the optical block.

If a linear motor having a large shape is used in the above-mentioned conventional transfer mechanism, even if the driving force of the linear motor is increased, the positioning action of the optical block with respect to a specific track of the optical disk is not affected by the linear motor and the optical block. It has a drawback that it cannot be performed accurately due to the overrun of the above.

Further, in the mechanism for supporting the optical block at two points in the moving direction of the optical block, there is a risk that the optical block is tilted (yawing), and as a result, reading and writing and writing on the optical disk cannot be performed well. ing.
SUMMARY OF THE INVENTION It is an object of the present invention to solve the above problems and to provide an optical block transfer mechanism capable of realizing high-speed seek of an optical block and accurate and quick positioning.

[0013]

According to the present invention, there is provided an optical disk device comprising an optical block for holding an optical head,
A configuration is adopted which has four linear motors which are provided to drive the optical block in the radial direction of the disk-shaped recording medium and are arranged point-symmetrically with respect to the center of gravity of the optical block.

[0014]

In the present invention, the four linear motors are arranged symmetrically with respect to the position of the center of gravity of the optical block.
By appropriately controlling the drive of each linear motor, it is possible to perform high-speed seeking of the optical block.
Positioning to a specific track on the disk can be achieved quickly and properly.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A preferred embodiment of the present invention will be described below with reference to the drawings. As shown in FIG. 1, the present invention comprises a chassis 2 supported in an outer housing 1, and a rotation drive device 4 for holding and holding an optical disk 3 on the chassis 2 and rotating the same. ing.

The rotary drive device 4 has a spindle motor 5 attached to the chassis 2 and a disk table 6 attached to the drive shaft of the spindle motor 5. The optical disc 3 is placed and held on the disc table 6 and the disc table 6 is held.
When the spindle motor 3 is driven to rotate, the optical disc 3 held above is rotated together with the disc table 6.

Then, in the radial direction of the optical disc 3,
An optical block 1 having an optical head which is moved by four linear motors 7, 8, 9 and 10 over the inner and outer circumferences thereof.
1 is arranged.

The optical block 11 having the above-mentioned optical head is constructed by incorporating a light source such as a semiconductor laser, a predetermined optical device including an objective lens 12 for guiding a light beam emitted from the light source, a photodetector and the like. ing. Then, by irradiating the optical disk surface with laser light and detecting return light from the optical disk, writing and / or reading of an information signal to / from the optical disk is performed. Reference numeral 11a denotes a notch portion formed so as not to collide with the optical disc 3 when moving in the radial direction of the optical disc 3.

Further, the linear motors 7, 8, 9, 10
As shown in FIG. 2, each of the moving member 13 and the fixed member 2
It is composed of 0 and. The moving member 13 has a bobbin 1 having a coil 14 of a linear motor wound around one end thereof.
5 is provided in the bobbin 15, and screw holes 16 and 17 for coupling for coupling with the coupling portion of the optical block 11 are provided.
In addition to that, energizing pins 18 and 19 for the coil 14 are provided.

The fixed member 20 of the linear motor is provided with a pair of upper and lower magnetic yokes 21 and 22 connected to each other along the moving direction of the moving member 13. A magnet 23 that generates a magnetic field in a direction orthogonal to the moving direction of the moving member 13 is provided on the lower yoke 22 on a surface facing the upper yoke 21. The yoke 21 penetrates the bobbin 15 around which the coil 14 is wound, and the bobbin 15 is movable along the moving direction of the moving member 13. In this way, each linear motor 7, 8, 9, 10
Is a coil 14, a bobbin 15, magnetic yokes 21, 22,
The moving member 13 can be moved at a predetermined speed by controlling the current flowing through the coil 14, which is composed of a magnet 23 and the like.

The four linear motors 7, 8 and
9 and 10 each use a relatively low torque and small size. As shown in FIG. 1, the linear motors 7 and 8 are opposed to each other, and the linear motors 9 and 10 are opposed to each other so that the center of gravity of the optical block 11 is It is arranged so as to be point-symmetrical.

Each of the linear motors 7, 8, 9, 1 having the above structure
The guide member 24 and 25, which are arranged to face each other on the chassis 2, penetrate and support the moving member 13 of 0. That is, the moving member 11 of the linear motors 7 and 9 is attached to the guide shaft 24 by the moving member 1 of the linear motors 8 and 10.
The guide shaft 3 is pierced and supported by the guide shaft 25. The ends of the moving member 13 have screw holes 16 and 17 for connecting the bobbin 15 at the four corners of the optical block 11.
It is connected via a screw to. Regarding the driving of these linear motors 7, 8, 9 and 10, they should be controlled by a control system including a microcomputer so that only one of the four motors or three of them can be driven. Good to do.

Since the present invention is constructed as described above,
By energizing the coil 14, the moving member 13 having the bobbin 15 is driven, so that the optical block 11 connected to the linear motors 7, 8, 9, 10 at the four corners.
Can be radially transferred along the guide shafts 24 and 25 over the inner and outer circumferences of the optical disc 3.

In this case, at the time of high-speed seek operation of the optical block 11 at a position separated by a predetermined distance or more, the linear motors 7, 8, 9, 10 at the four corners arranged point-symmetrically with respect to the center of gravity of the optical block 11. By driving all of the above, the optical block 11 is accelerated / decelerated.
Further, the positioning operation of the optical block 11 to the specific track with respect to the optical disk 3 uses the linear motors 9 and 10 for driving toward the center of the optical disk 3, and the other pair of linear motors 7 and 8 moves toward the outer side of the optical disk 3. The linear motors 7, 8, 9, 1 are not used to drive all of them at the same time as in the conventional example.
It is possible to drive two sets of 0 in opposite directions (push / pull state). Therefore, the positioning operation to the specific track on the optical disc 3 can be performed accurately and quickly.

When the optical block 11 is moved by a minute stroke, accurate transfer can be achieved by driving only two linear motors. Further, by appropriately controlling the driving of, for example, a set of linear motors 7 and 10 or a set of linear motors 8 and 9 which are on a diagonal line with respect to the center of gravity of the optical block 11,
It is possible to suppress or correct the inclination (yawing) of the optical block 11 in the direction perpendicular to the plane.

[0026]

Since the present invention has the four linear motors arranged point-symmetrically with respect to the center of gravity of the optical block as described above, it is possible to achieve high-speed seek of the optical block. .. Further, since it is not necessary to increase the number of turns of the coil or to strengthen the magnet, each linear motor can be downsized. As a result, it is possible to reduce the size and thickness of the optical disk device, and it is possible to reduce the cost by improving the mass productivity of the linear motor.

Further, by appropriately combining and driving the four linear motors, the control range of the drive operation of the optical block can be expanded, so that the positioning operation of the optical block to the specific track on the optical disk can be performed accurately and quickly. be able to.

Furthermore, since the optical block is supported by four linear motors, the inclination (yawing) of the optical block can be effectively suppressed, and excellent information signal writing and / or reading can be performed.

[Brief description of drawings]

FIG. 1 is a plan view showing a transfer mechanism of an optical block according to the present invention.

FIG. 2 is a perspective view showing a linear motor.

FIG. 3 is a plan view showing a conventional optical block transfer mechanism.

[Explanation of symbols]

 3 ... Disk 11 ... Optical block 7, 8, 9, 10 ... Linear motor

[Procedure amendment]

[Submission date] June 5, 1992

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] Full text

[Correction method] Change

[Correction content]

[Document name] Statement

Patent application title: Optical block transfer mechanism

[Claims]

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical block transfer mechanism having an optical head for writing and / or reading information signals to and from a disk-shaped recording medium such as an optical disk or a magneto-optical disk.

[0002]

2. Description of the Related Art Conventionally, there has been proposed an optical disc recording and / or reproducing apparatus for writing and / or reading an information signal on a disc-shaped recording medium such as an optical disc or a magneto-optical disc. As shown in FIG. 3, such an optical disk recording and / or reproducing apparatus has a chassis 102 supported in an outer casing 101, and holds the optical disk 3 on the chassis 102 so as to be rotatable. ..

The rotating operation of the optical disk 3 includes a spindle motor 103 mounted on the chassis 102 and a disk table 104 mounted on the drive shaft of the spindle motor 103.
The optical disk 3 is mounted on the optical disk 4.

Then, a pair of linear motors 106 and 10 are provided so as to face the signal recording surface of the optical disc 3.
An optical block 105 having an optical head that is moved in the radial direction over the inner and outer circumferences of the optical disc 3 by means of 7 is arranged on the moving base 120.

Optical block 10 having the above optical head
Reference numeral 5 includes a light source such as a semiconductor laser, a predetermined optical device including an objective lens 108 for guiding a light beam emitted from the light source, a photodetector, and the like. Then, by irradiating the optical disc with a light beam and detecting the reflected light from the optical disc, writing and / or reading of an information signal with respect to the optical disc is performed.

The movable base 120 is the chassis 1
The optical disc 3 is supported by two guide shafts 113 and 114 arranged in parallel with each other in the radial direction of the optical disc 3 via a roller member. That is, the moving base 120 uses the roller members as the guide shafts 113, 1
The optical disc 3 is guided by the optical disc 14 and is movable in the radial direction of the optical disc 3. In this example, two roller members 12 are provided for the upper guide shaft 113 in the figure.
1, 122 is also the other guide shaft 114 on the lower side in the drawing.
On the other hand, the roller members 123 are each rollable.

Next, two linear motors 106, 107 for moving the moving base 120 in the length direction of the guide shafts 113, 114 are attached to both sides of the moving base 120. This linear motor 106, 10
7 is composed of a fixed member 110 and a moving member 109, respectively. The fixing member 110 of the linear motor is composed of a magnet or the like that forms a magnetic path with the upper and lower magnetic yokes. And a pair of fixing members 110,
110 are arranged on the chassis 102 in parallel with the guide shafts 113 and 114.

On the other hand, the moving member 109 is composed of a bobbin 112 around which a coil 111 is wound. An energizing pin to which the terminal of the coil 111 is connected is provided at the base end of the bobbin 112. The bobbin 112 of the moving member 109 is connected to the bobbin 112 on both sides of the moving base 120 by screwing the bobbin 112 at both sides with screw members 119. The moving members 109 and 109 attached to both sides of the moving base 120 are inserted and attached to the fixed members 110 and 110, respectively.

Therefore, the linear motors 106 and 107 are
Is configured such that the moving member 109 can be moved in the longitudinal direction of the fixed member 110 by applying a predetermined current to the coil 111 via the energizing pin.

In the optical block transfer mechanism having the above structure, the pair of linear motors 106, 1 as described above.
When the ends of the coils 111 of 07 are simultaneously energized and the moving member 109 is moved in the longitudinal direction of the fixed member 110, the roller members 121 mounted on the moving base 120 along with the moving members 109, 122 and 123 roll along the length direction of the two guide shafts 113 and 114, and the moving base 120 is moved. This moving base 1
By the movement of 20, the optical block 105 provided in the moving base 120 is moved in the radial direction over the inner and outer circumferences of the optical disc 3 to write and / or read an information signal on the optical disc 3. It can be carried out.

[0011]

In the above-mentioned optical block transfer mechanism, the weight of the optical block including the optical head for writing and / or reading the information signal is generally relatively heavy. Therefore, with two linear motors for driving the optical block as in the conventional example, it is difficult to realize high-speed movement of the optical disc in the radial direction of the optical disc (so-called seek operation of the optical block). is there. In particular, when miniaturization and thinning are required, there is a limit to improving the performance of the linear motor, which is extremely difficult.

Therefore, it is not impossible to consider increasing the number of turns of the coil with respect to the bobbin or increasing the magnetic force of the magnet to increase the thrust of the linear motor in the conventional transfer mechanism. However, increasing the number of turns of the coil increases the weight of the bobbin serving as the moving part of the linear motor and hinders quick movement operation and stop, and increasing the magnetic force of the magnet increases the magnetism. There is a problem that the leakage flux from the magnetic field increases, and this leakage flux may adversely affect the elements such as the optical head forming the optical block in the moving base.

If a linear motor having a large shape is used in the above-mentioned conventional transfer mechanism, the positioning action of the optical block to a specific track of the optical disk is not affected by the linear motor and the optical block even if the thrust of the linear motor increases. It has a drawback that it cannot be performed accurately due to the overrun of the above.

Further, in the moving direction 2 with respect to the optical block.
In the mechanism for driving the moving base at a certain position, there is a risk that tilting (yawing) of the optical block occurs, and as a result, writing and / or reading of the optical disk cannot be performed well. SUMMARY OF THE INVENTION It is an object of the present invention to solve the above problems and to provide an optical block transfer mechanism capable of realizing high-speed seek of an optical block and accurate and quick positioning.

[0015]

According to the present invention, there is provided an optical disk device comprising an optical block for holding an optical head,
The optical block is provided to drive the optical disk in the radial direction of the disk-shaped recording medium, and a configuration having four linear motors arranged point-symmetrically with respect to the center of gravity of the optical block is adopted.

[0016]

In the present invention, the four linear motors are arranged symmetrically with respect to the position of the center of gravity of the optical block.
By appropriately controlling the drive of each linear motor, it is possible to perform high-speed seeking of the optical block.
Positioning to a specific track on the optical disk can be achieved quickly and appropriately.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A preferred embodiment of the present invention will be described below with reference to the drawings. As shown in FIG. 1, the present invention has a chassis 2 supported in an outer housing 1, and a disk table 6 for holding an optical disk 3 on the chassis 2.
A spindle motor 5 for rotating the disk table 6 is provided. On the disc table 6,
The optical disc 3 is placed and held. The optical disc 3 held on the disc table 6 is rotated together with the disc table 6 by the spindle motor 5 being driven to rotate.

Then, the four linear motors 7, 8, 9 are arranged so as to face the signal recording surface of the optical disc 3.
A movable base 4 provided with an optical block 11 having an optical head that is moved by 10 over the inner and outer circumferences of the optical disc 3 is attached.

Optical block 11 having the above optical head
Includes a light source such as a semiconductor laser, a predetermined optical device including an objective lens 12 for guiding a light beam emitted from the light source, a photodetector, and the like. Then, by irradiating the optical disk surface with laser light and detecting return light from the optical disk, writing and / or reading of an information signal with respect to the optical disk is performed. It should be noted that, when the optical disk 3 is moved in the radial direction on the side of the moving base 4 facing the disk table 6,
The notch 4a is provided so as not to collide with the disc table 6.

The moving base 4 is supported by two guide shafts 24, 25 arranged in parallel with each other in the radial direction of the optical disk 3 on the chassis 2 via a roller member. That is, the movable base 4 is configured to be movable in the radial direction of the optical disc 3 by guiding the roller member to the guide shafts 24 and 25. In this example, the roller members 26 and 27 can roll on one upper guide shaft 24 in FIG. 1, and the roller member 28 can roll on the other lower guide shaft 25 in FIG. Has been done.

Next, as shown in FIG. 2, the four linear motors 7, 8, 9 and 10 for driving the moving base 4 in the longitudinal direction of the guide shafts 24 and 25 are respectively connected to the moving members 13 as shown in FIG. It is composed of a fixing member 20. The moving member 13 is provided with a bobbin 15 on one end of which a coil 14 of a linear motor is wound. The bobbin 15 has a connecting screw hole 1 for connecting to both sides of the moving base 4.
6 and 17, and energization pins 18 and 19 connected to the terminals of the coil 14 are provided.
That is, the ends of the wire drawn from the coil 14 are wound around the energizing pins 18 and 19 and soldered through the groove 15a of the bobbin 15, respectively. Then, the moving member 13 configured as described above is
The movable base 4 is attached so as to project laterally from two positions on both sides of the movable base 4. The moving member 13 is attached to the moving base 4 by being connected to the coupling screw holes 16 and 17 provided on the base end side of the bobbin 15 via a screw member 29.

Further, the fixing member 20 of the linear motor is 4
Corresponding to each moving member 13, a pair of two fixed members are arranged on the chassis 2 in parallel with the guide shafts 24 and 25. The fixed member 20 includes a pair of upper and lower magnetic yokes 21 along the moving direction of the moving member 13.
Both ends of 22 are connected and provided. A magnet 23 that generates a magnetic field in a direction perpendicular to the moving direction of the moving member 13 is provided on the lower magnetic yoke 22 on a surface facing the upper magnetic yoke 21. The bobbin 15 around which the coil 14 of the moving member 13 is wound is inserted through the magnetic yoke 21.

Therefore, the linear motors 7, 8, 9, 1
0 indicates each coil 14 via the energizing pins 18 and 19.
When a predetermined current is applied to the moving member 13,
Are movable in the length direction of the fixing member 20. Therefore, as described above, each linear motor 7, 8, 9, 10
Are the coil 14, the bobbin 15, and the magnetic yoke 2, respectively.
1, 22, a magnet 23, etc., and by controlling the current flowing through the coil 14, the moving base 4 can be driven in the radial direction of the optical disc 3 at a predetermined speed.

Here, the four linear motors 7, 8 and
Respectively low thrust and small size are used as 9 and 10, and the linear motors 7 and 8 are opposed to each other and the linear motors 9 and 10 are opposed to each other as shown in FIG. The optical blocks 11 are arranged so as to be point-symmetric with respect to the center of gravity of the optical block 11. In addition,
Regarding the driving of these linear motors 7, 8, 9 and 10, they can be controlled by a control system including a microcomputer, so that two of the four motors can be driven, or all four can be driven independently. It is good to be able to drive.

Since the present invention is constructed as described above,
By energizing the coil 14, the moving member 13 having the bobbin 15 is driven as a linear motor. By driving the moving member 13, the moving base 4 to which the linear motors 7, 8, 9, 10 are connected is driven along the length direction of the guide shafts 24, 25, and the moving base 4 is provided. The optical block 11 can be transferred in the radial direction over the inner and outer circumferences of the optical disc 3.

In this case, during high-speed seek operation of the optical block 11 in the movable base 4 to a position separated by a predetermined distance or more, the linear motors 7 and 8 arranged point-symmetrically with respect to the center of gravity of the optical block 11. , 9 and 10 are all driven to accelerate and decelerate the moving base 4. Further, the positioning operation of the optical block 11 to the optical disk 3 on a specific track is performed by driving the linear motors 9 and 10 toward the center of the optical disc 3, and the other pair of linear motors 7 and 8 is used to drive the optical disc 3 toward the outside. For example, the linear motors 7 and 8 are not driven at the same time as in the conventional example.
Two sets of 9 and 10 can be driven in opposite directions (push / pull state) and used. Therefore, the positioning operation to the specific track on the optical disc 3 can be performed accurately and quickly.

When the optical block 11 is moved by a minute stroke, accurate transfer can be achieved by driving only two linear motors. Further, by appropriately controlling the driving of, for example, a set of linear motors 7 and 10 or a set of linear motors 8 and 9 which are on a diagonal line with respect to the center of gravity of the optical block 11,
It is possible to suppress or correct the inclination (yawing) of the optical block 11 in the direction perpendicular to the plane.

[0028]

Since the present invention has four linear motors arranged point-symmetrically with respect to the center of gravity of the optical block as described above, it is possible to achieve high-speed seek of the optical block. Further, since it is not necessary to increase the number of turns of the coil or to strengthen the magnet, each linear motor can be downsized. As a result, it is possible to reduce the size and thickness of the optical disk device, and it is possible to reduce the cost by improving the mass productivity of the linear motor.

Further, by appropriately driving the four linear motors in combination, the control range of the drive operation of the optical block can be expanded, so that the positioning operation of the optical block to the specific track on the optical disk can be performed accurately and quickly. be able to.

Further, since the optical block is driven by four linear motors, the inclination (yawing) of the optical block can be effectively suppressed, and excellent information signal writing and / or reading can be performed.

[Brief description of drawings]

FIG. 1 is a plan view showing a transfer mechanism of an optical block according to the present invention.

FIG. 2 is a perspective view showing a linear motor.

FIG. 3 is a plan view showing a conventional optical block transfer mechanism.

[Explanation of Codes] 3 ... Disk 11 ... Optical Block 7, 8, 9, 10 ... Linear Motor

[Procedure Amendment 2]

[Document name to be corrected] Drawing

[Correction target item name] All drawings

[Correction method] Change

[Correction content]

[Figure 1]

[Fig. 2]

[Figure 3]

Claims (1)

[Claims] 1. An optical disk device, comprising: an optical block for holding an optical head; and an optical block, which is provided for driving and operating the optical block in a radial direction of a disk-shaped recording medium, and is point-symmetric with respect to the center of gravity of the optical block. An optical block transfer mechanism, comprising: four linear motors arranged.