JPH05342505A - Bias magnetic field applying device for magneto-optical disk device - Google Patents

Abstract

(57) [Abstract] [PROBLEMS] To provide a bias magnetic field applying device for a magneto-optical disk device capable of performing magnetic field modulation overwrite without trouble even when a 5.25-inch ISO standard disk cartridge is used. A magnetic head for applying a bias magnetic field to a magneto-optical disk is mounted on a magnetic head carriage that moves in the radial direction of the magneto-optical disk. , A cantilever whose base is fixed to the magnetic head carriage
Support the load beam at the free end of the load beam , and orient this cantilevered load beam so that its base is located on the disk rotation center side of the magneto-optical disk and its free end is located on the outer peripheral side. Bias magnetic field applying device for a specified magneto-optical disk device.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to application of a bias magnetic field to a magneto-optical disk device in which a magnetic head for applying a bias magnetic field to the magneto-optical disk is mounted on a carriage that moves in the radial direction of the magneto-optical disk. Regarding the device.

[0002]

2. Description of the Related Art For example, a magneto-optical disk device capable of repetitively recording information on a magneto-optical disk emits a laser beam of high power emitted from an optical head toward a recording layer of the loaded magneto-optical disk. Continuously converge, raise the temperature to the Curie temperature, and apply a bias magnetic field by the bias magnetic field generator (magnetic head) in the temperature rising state to align the magnetization direction of the magnetic body in the same direction as at initialization. After that, the bias magnetic field is reversed to intermittently converge the laser light having a large power on the recording layer, thereby reversing the magnetization direction and recording the information.

In the magneto-optical disk device of the type in which the magneto-optical disk is rotated for erasing and recording as described above,
IS for 5.25 inch discs, as shown in FIG.
The O-standard (international standard) disk cartridge 11 can be used. This disk cartridge 11 is
A double-sided disc conforming to the ISO standard format is loaded, and an opening 11a is formed in the radial direction of the loaded double-sided disc from the disc rotation center C side to the outer wall portion 11b. When the disc cartridge 11 is loaded in the magneto-optical disc device, a large-sized fixed type bias electromagnet (or permanent magnet) 18
Is inserted over substantially the entire area of the opening 11a. In this state, a bias magnetic field is applied to the loaded magneto-optical disc.

In the magneto-optical disk device having such a structure, in order to rewrite the information of one track, it is necessary to rotate the magneto-optical disk for erasing and recording respectively, which is a disadvantage that the recording speed is slow. Therefore, recently, by selectively applying a magnetic field of S or N to a minute region corresponding to a region where laser light is focused, it is possible to rewrite information by rotating the disc once. A modulation overwrite type magneto-optical disk device has been proposed.

By the way, the ISO standard disc cartridge 11 is loaded with only a double-sided disc as described above, but the disc cartridge 11 has a thinner single-sided disc (single disc) than the double-sided disc. It is practically possible to load and use 12. That is, in the above-described magneto-optical disk device of the magnetic field modulation overwrite type, it is necessary to apply a high-speed modulated magnetic field to the magneto-optical disk 12 in order to realize rapid overwrite. Load a single-sided disc into the disc cartridge 11,
It can be considered to be used for the magnetic field modulation overwrite type magneto-optical disk device.

In this case, in order to apply a high-speed modulated magnetic field to the magneto-optical disk 12, it is necessary to reduce the size of the magnetic head and bring it extremely close to the disk recording layer. Therefore, as shown in the figure, for example, a magnetic head mounting portion 16 that is movable in the radial direction of the magneto-optical disk 12.
A cantilevered flexure 15 having its base portion positioned on the outer side in the radial direction and fixed thereto is attached, and a magnetic head 25 is supported at the tip of the flexure 15 to provide an air floating type structure.

However, in such a structure, since there is almost no dimensional allowance, when the magnetic head 25 is moved toward the outer peripheral side of the magneto-optical disk 12, the flexure 15 has its rear portion at the outer wall portion of the disk cartridge 11. 1
The magnetic head 25 cannot be properly moved with respect to the outer peripheral track of the magneto-optical disk 12 because it is brought into contact with the outer peripheral track 1b, and magnetic field modulation overwrite cannot be performed in the recording area of the outer peripheral track. Occurs.

[0008]

SUMMARY OF THE INVENTION The present invention is based on the above-mentioned awareness of problems.
It is an object of the present invention to provide a bias magnetic field applying device for a magneto-optical disk device that can perform magnetic field modulation overwrite without trouble even when a 25-inch ISO standard disk cartridge is used.

[0009]

SUMMARY OF THE INVENTION The present invention, which achieves the above objects, therefore comprises:
In a bias magnetic field applying device for a magneto-optical disk device, wherein a magnetic head for applying a bias magnetic field to the magneto-optical disk is mounted on a carriage that moves in the radial direction of the magneto-optical disk, the magnetic head is composed of The cantilevered plate-like member fixed to the carriage is supported at the free end of the cantilever, and the base of the cantilevered member is located at the disk rotation center side of the magneto-optical disk, and the free end of the cantilever is The feature is that the direction is determined so as to be located on the outer peripheral side.

[0010]

The present invention will be described below with reference to the illustrated embodiments.
9 is a plan view showing a magneto-optical disk device 20 of the magnetic field modulation overwrite type to which the present invention is applied.
Is a side view thereof. The magneto-optical disk device 20 has a cartridge holder 22, and the cartridge holder 22 is configured so that an ISO standard disk cartridge 11 containing a 5.25-inch magneto-optical disk 12 can be inserted. The magneto-optical disk device 20 also moves the optical head (objective lens actuator) 24 in the radial direction of the magneto-optical disk 12 along the optical head section 21 and the linear bearing 51 (FIG. 7) fixed to the optical head section 21. An optical head carriage 23 for moving the magnetic head 25 and a magnetic head carriage 26 for moving the magnetic head 25 in the radial direction of the magneto-optical disk 12 are provided.

The cartridge holder 22 includes the optical head section 2.
It is configured to be movable up and down with respect to 1, and is at a position away from the optical head portion 21 when the disc cartridge 11 is attached and detached. When the disc cartridge 11 is inserted, the disc cartridge 11 moves toward the optical head portion 21. The magneto-optical disk 12 can be set at a predetermined position.

Outside the cartridge holder 22, the guide rollers 50 provided on the optical head portion 21 are slidable in the directions of arrows A and B in FIG. Guide cam plate 35
Is provided. The left and right guide cam plates 35 respectively have substantially crank-shaped holder cam grooves 40 and 42 and head cam grooves 41 and 43 formed at four positions. Left and right fixed cam plates 49 are provided outside the guide cam plate 35, and the left and right fixed cam plates 49 have holder cam grooves 40, 42 of the left and right guide cam plates 35.
Also, vertical guide cam grooves 45, 46, 47 are formed in the vertical direction so as to correspond to the head cam groove 41.

On the left and right side surfaces of the cartridge holder 22 with respect to the disc moving direction, cam pins 36,
38, the cam pin 36 is inserted into the holder cam groove 40 and the vertical guide cam groove 45, and the cam pin 38 is inserted into the holder cam groove 42 and the vertical guide cam groove 47. Cam pins 37 and 39 are provided on the left and right side surfaces of the magnetic head carriage base 28. The cam pins 37 are inserted into the head cam groove 41 and the vertical guide cam groove 46, and the cam pin 39 serves as the head cam. It is inserted into the groove 43. In addition, 54 in FIG. 9 is
This is the shutter of the disk cartridge 11.

A rack plate 59 and a switch operating plate 60 are fixed to the guide cam plate 35. The optical head portion 21 is provided with a drive motor 61 and a gear box 62 for transmitting the rotation of the drive motor 61. The rotation of the drive motor 61 is transmitted through the pinion gear 63 to the rack plate 5.
9 is transmitted as a linear motion. Therefore, when the drive motor 61 is driven, the guide cam plate 35 moves to the rack plate 59.
Via arrow to move in the direction of arrow A in FIG. As a result, the disc cartridge 11 includes the guide pins 36 and 38, the holder cam grooves 40 and 42, and the vertical guide cam groove 45.
By the action with 47, the lower surface thereof descends until it comes into contact with the upper surface 50a of the guide roller 50 serving as a reference surface provided on the optical head portion 21, and at the same time, the magnetic head carriage base 28 moves with the guide pins 37, 39. Cam groove for holder 4
1 and 43 and the action of the vertical guide cam groove 46,
It is lowered to a predetermined position.

The main body of the apparatus has first, second and third detection switches 65, 66 and 6 corresponding to the switch operation plate 60.
7 is provided. These detection switches 65, 6
6, 67 are switch levers 65a, 66a,
67a. Detection switches 65, 66, 67
Is a switch operation plate 6 that moves together with the guide cam plate 35.
The switch lever 65a, 66a, 67a is pressed or released by 0 to turn it on or off, and the position of the guide cam plate 35 is detected based on this. By this detection, it is detected which state the disk cartridge 11 and the magnetic head carriage base 28 are currently in. That is, in the switch operating plate 60, the first detection switch 65 is turned off and the second detection switch 66 and the third detection switch 67 are turned on in the state of FIG. 4, and the first detection switch 65 is turned on in the state of FIG. And the third detection switch 67 are turned off and the second detection switch 66 is turned on. In the state of FIG. 6, the first detection switch 65 is turned on and the second detection switch 66 and the third detection switch 67 are turned on. It has been turned off. By discriminating these different bit signals by the discriminating circuit, it is possible to discriminate whether the magneto-optical disk device 20 is at the detaching position, the mid-loading position, or the recording / reproducing position.

As shown in FIG. 7, the optical head carriage 23 is supported by a linear bearing 51 so as to be movable along the radial direction of the magneto-optical disk 12.
Coil 52 fixed to both ends of optical head carriage 23
Are driven around a magnetic circuit 53 by a linear motor. The linear bearing 51 includes a fixed member 71, a movable member 72, and a ball 73 interposed between the fixed member 71 and the movable member 72. The fixed member 71 is a member that is attached to the optical head portion 21 side and that is formed in a substantially U-shape and is elongated. The movable member 72 is attached to the optical head carriage 23 side and compared to the fixed member 71. Then, it is a member that is narrow and substantially U-shaped and long. Rolling grooves are formed on the opposed side surfaces of the fixed member 71 and the movable member 72, and a ball 73 is fitted between the opposed rolling grooves.

Further, the optical head carriage 23 uses the objective lens for the light flux from the laser light source to produce the magneto-optical disk 12.
To read the magneto-optical recording signal by receiving the reflected light from the magneto-optical disk 12 during reproduction, and converging the laser light onto the magneto-optical disk 12 with a power higher than during reproduction to record the temperature of the recording layer. The Curie temperature is raised and information is overwritten on the recording layer in cooperation with the magnetic head 25.

Further, as shown in FIG. 7, the magnetic head carriage 26 is movably supported by a linear bearing 55 attached to the magnetic head carriage base 28 along the radial direction of the magneto-optical disk 12.
Coil 5 fixed to both ends of magnetic head carriage 26
6 is driven by a linear motor configured by arranging 6 around the magnetic circuit 57. The linear bearing 55 is composed of a fixed member 75, a movable member 76, and a ball 77 interposed between the fixed member 75 and the movable member 76. The fixing member 75 is a member that is attached to the optical head portion 21 side and that is formed in a substantially U shape and is elongated.
The movable member 76 is a member that is attached to the optical head carriage 23 side, is narrower than the fixed member 75, and is formed in a substantially U shape and long. Rolling grooves are formed on the opposite side surfaces of the fixed member 75 and the movable member 76, and a ball 77 is fitted between the facing rolling grooves.

At the end of the magnetic head carriage 26, two sets of photo reflectors 3 each having a light emitting / receiving element are provided.
0 and 31 are provided, and a reflection plate 32 is attached to the tip of the reflection plate holding portion 27 extending in the moving direction of the optical head carriage 23. Both carriages 23, 2
No. 6 is set so that the positions of both heads 24 and 25 coincide when the outputs from the two light receiving elements become equal.

The optical head carriage 23 is also driven in the radial direction of the magneto-optical disk 12 by a signal from an external control device such as a computer, and the magnetic head carriage 26.
Is controlled by a synchronizing circuit (not shown) so that the outputs from the two light receiving elements become equal. This allows
The magnetic head carriage 26 can be moved in synchronization with the optical head carriage 23.

1 to 3 are enlarged views of the periphery of the magnetic head 25, respectively. On the back surface of the magnetic head carriage 26, a cantilever flexure (plate-shaped member) 15 is fixed by a fixing screw 69 with its base located on the disk rotation center 12a side of the magneto-optical disk 12. A magnetic head 25 is attached to the free end of the flexure 15 facing the outer peripheral side of the magneto-optical disk 12. The flexure 15 has a
The magnetic head pressing plate 70 bends downward until it comes into contact with the magnetic head pressing plate 70, and as shown in FIG.
In this state, when the drive motor 61 is driven, the guide cam plate 35 slides, whereby the disc cartridge 11 is lowered to a predetermined position. After that, since the magneto-optical disk 12 is rotated, the air floating magnetic head 25 approaching the disk 12 thereafter is
When it receives the wind pressure due to the rotation of the disk, it warps upward, and comes into a state of approaching the surface of the disk 12 at a very close distance as shown in FIG.

At this time, the magnetic head 25, which is moved in the radial direction on the magneto-optical disk 12 in the disk cartridge 11, has its base positioned on the disk rotation center side of the magneto-optical disk 12 as described above. Since it is attached to the free end of the cantilever flexure 15,
There is no inconvenience such as contacting the rear portion of the flexure 15 with the outer wall portion 11b. That is, as described in this embodiment,
A 5.25-inch I / O device is used for a magneto-optical disk device that can rewrite information by rotating the magneto-optical disk once.
Even when the SO standard disk cartridge 11 is used, magnetic field modulation overwriting can be performed in all recording areas without any trouble.

[0023]

As described above, according to the present invention, the magnetic head is supported on the free end of the cantilevered plate member whose base is fixed to the carriage, and the cantilevered plate member is Even if a 5.25-inch ISO standard disk cartridge is used, all recording is done because the base is located on the disk rotation center side of the magneto-optical disk and the free end is located on the outer peripheral side. In the area, it is possible to overwrite the magnetic field modulation without any trouble.

[Brief description of drawings]

FIG. 1 is a side view of an essential part showing a state in which a magneto-optical disk device of this embodiment is in a removable position.

FIG. 2 is a side view showing a state at a recording / reproducing position in FIG.

FIG. 3 is a plan view showing a main part of FIG.

FIG. 4 is a side view showing a state in which the magneto-optical disk device of the embodiment is in a removable position.

FIG. 5 is a side view showing a state in which the magneto-optical disk device of the embodiment is in the loading midway position.

FIG. 6 is a side view showing a state in which the magneto-optical disk device of the embodiment is in a recording / reproducing position.

7 is a diagram showing the magneto-optical disk device of FIG. 4 viewed from the direction of arrow D in FIG.

8 is a diagram showing the magneto-optical disk device of FIG. 6 viewed from the direction of arrow D in FIG.

FIG. 9 is a plan view showing the entire magneto-optical disk apparatus of the same embodiment.

FIG. 10 is a side sectional view of an ISO standard disk cartridge.

[Explanation of symbols]

 11 disk cartridge 12 magneto-optical disk 12a disk rotation center 15 flexure (plate-shaped member) 20 magneto-optical disk device 21 optical head part 22 cartridge holder 23 optical head carriage 24 optical head 25 magnetic head 26 magnetic head carriage 70 magnetic head pressing plate

─────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] August 30, 1993

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] 0002

[Correction method] Change

[Correction content]

[0002]

2. Description of the Related Art For example, in a conventional magneto-optical disk device capable of repeatedly recording information on a magneto-optical disk, a via layer is provided toward a recording layer of the loaded magneto-optical disk.
Bias for initialization by magnetic field generator (magnetic head)
After applying a magnetic field, the laser light with high power emitted from the optical head is continuously focused to produce a magneto-optical disk.
Raise the temperature of the recording layer to the Curie temperature ,
After the coercive force is eliminated, the recording layer is cooled during the cooling process.
Magnetization direction is the same as the initialization bias magnetic field,
After so-called initialization, the magnetic field is reversed to intermittently converge high power laser light on the recording layer, thereby reversing the direction of magnetization and recording information.

[Procedure Amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0006

[Correction method] Change

[Correction content]

In this case, in order to apply a high-speed modulated magnetic field to the magneto-optical disk 12, it is necessary to reduce the size of the magnetic head and bring it extremely close to the disk recording layer. Therefore, as shown in the figure, for example, a magnetic head mounting portion 16 that is movable in the radial direction of the magneto-optical disk 12.
The cantilevered load beam 15 whose base is located at the outer side in the radial direction is fixed to the load bead.
A structure in which the magnetic head 25 is supported at the tip of the frame 15 and is of an air floating type can be considered.

[Procedure 3]

[Document name to be amended] Statement

[Correction target item name] 0007

[Correction method] Change

[Correction content]

However, in such a structure, since there is almost no dimensional allowance, when the magnetic head 25 is moved toward the outer peripheral side of the magneto-optical disk 12, the load beam 15 causes the rear part thereof to the outer wall of the disk cartridge 11. Part 1
The magnetic head 25 cannot be properly moved with respect to the outer peripheral track of the magneto-optical disk 12 by being brought into contact with the outer peripheral track 1b, and magnetic field modulation overwrite cannot be performed in the recording area of the outer peripheral track. Occurs.

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0021

[Correction method] Change

[Correction content]

1 to 3 are enlarged views of the periphery of the magnetic head 25, respectively. On the back surface of the magnetic head carriage 26, a cantilevered load beam (plate-shaped member) 15 is fixed by a fixing screw 69 with its base located on the disk rotation center 12a side of the magneto-optical disk 12. Load
A magnetic head 25 is attached to the free end of the beam 15 facing the outer peripheral side of the magneto-optical disk 12. When the load beam 15 is in the detached position of FIG.
The magnetic head pressing plate 70 bends downward until it comes into contact with the magnetic head pressing plate 70, and as shown in FIG.
In this state, when the drive motor 61 is driven, the guide cam plate 35 slides, whereby the disc cartridge 11 is lowered to a predetermined position. After that, since the magneto-optical disk 12 is rotated, the magnetic head 2 having an air floating slider surface that approaches the disk 12 thereafter.
5 is the load from the load beam 15 and the rotating magneto-optical device.
Stable at the position where the wind pressure by the disc 12 is balanced,
It becomes substantially parallel to the disk 12, and as shown in FIG.
The disk 12 is brought into close proximity to the surface of the disk 12 at a very short distance.

[Procedure Amendment 5]

[Document name to be amended] Statement

[Name of item to be corrected] 0022

[Correction method] Change

[Correction content]

At this time, the magnetic head 25, which is moved in the radial direction on the magneto-optical disk 12 in the disk cartridge 11, has its base positioned on the disk rotation center side of the magneto-optical disk 12 as described above. Cantilever road
Since it is attached to the free end of the beam 15,
The inconvenience of bringing the rear portion of the load beam 15 into contact with the outer wall portion 11b does not occur. That is, as described in this embodiment,
A 5.25-inch I / O device is used for a magneto-optical disk device that can rewrite information by rotating the magneto-optical disk once.
Even when the SO standard disk cartridge 11 is used, magnetic field modulation overwriting can be performed in all recording areas without any trouble.

[Procedure Amendment 6]

[Document name to be amended] Statement

[Correction target item name] Explanation of code

[Correction method] Change

[Correction content]

[Description of Reference Signs] 11 disk cartridge 12 magneto-optical disk 12a disk rotation center 15 load beam (plate-shaped member) 20 magneto-optical disk device 21 optical head unit 22 cartridge holder 23 optical head carriage 24 optical head 25 magnetic head 26 magnetic head carriage 70 Magnetic head holding plate

[Procedure Amendment 7]

[Document name to be corrected] Drawing

[Name of item to be corrected] Figure 7

[Correction method] Change

[Correction content]

[Figure 7]

[Procedure Amendment 8]

[Document name to be corrected] Drawing

[Correction target item name] Figure 8

[Correction method] Change

[Correction content]

[Figure 8]

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Isao Okuda 2-36-9 Maenocho, Itabashi-ku, Tokyo Asahi Kogaku Kogyo Co., Ltd.

Claims (1)

[Claims] 1. A bias magnetic field applying apparatus for a magneto-optical disk apparatus, wherein a magnetic head for applying a bias magnetic field to a magneto-optical disk is mounted on a carriage that moves in the radial direction of the magneto-optical disk. The base is supported on the free end of the cantilevered plate member fixed to the carriage, and the cantilevered plate member is located at the base of the magneto-optical disk on the disk rotation center side. A bias magnetic field applying device for a magneto-optical disk device, characterized in that the direction is determined so that the free end portion is located on the outer peripheral side.