JPH0553005B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention relates to an information recording device, and more specifically, a disk having a magnetic film is rotated, and information signals are recorded on the magnetic film concentrically or spirally using a light beam. It relates to an information recording device. [Prior Art] Among the information recording devices described above, there is one generally referred to as a magneto-optical disk device, which uses a disk in which a thin film of ferromagnetic material is formed on a non-magnetic material as a recording medium. During recording, the magnetic film on the recording medium is magnetized in advance so as to be oriented in the perpendicular direction. Then, while an external magnetic field is applied, a light beam modulated according to the information is irradiated onto the magnetic film from a recording section composed of a laser light source, an imaging lens, and the like. The area irradiated with the light beam is
When the temperature is raised by light energy and reaches the Curie point temperature (approximately 160°C), the magnetization direction becomes disordered. Next, as the recording medium moves, the position of the light beam moves to another part, the temperature decreases,
It is remagnetized by external magnetic flux, with its magnetization direction reversed to that of its surroundings. In this way, information is stored in the magnetic film as a reversal of magnetization, forming a signal train. On the other hand, when reproducing (reading) information, a semiconductor laser in a reproducing section is oscillated, the light beam is polarized by a polarizer, and is irradiated onto a signal train formed on a magnetic film. Due to the magnetic Karr effect at that time,
The light beam is rotated and reflected according to the magnetization direction of the irradiated part. This reflected light is separated from the incident light by a beam splinter or the like in the reproduction section, guided to a light receiving element through an analyzer, and information is reproduced by detecting the magnetization direction from the polarization direction. Incidentally, the feature of magneto-optical disks is that they can be recorded and reproduced as well as re-recorded, and unnecessary information can be erased. When erasing recorded bits, the recording medium is rotated and a light beam is irradiated onto the recording bit part while tracking the recording bit string, and this part is raised to the Curie point once, and then the part of the recording medium other than the recording pits is erased. Erasing is performed by cooling while applying a direct current bias magnetic field in the same direction as the magnetization direction of the disc, in preparation for re-recording. Conventionally, there are permanent magnets and electromagnets as bias magnets that provide such a DC bias magnetic field.
In any case, the directions of the magnetic fields must be reversed during recording and erasing. Therefore, in the method of applying a DC bias magnetic field using a permanent magnet, the rotation direction of the magnet is directly reversed, and in the method of applying a DC bias magnetic field using an electromagnet, the direction of the current is indirectly reversed. The directions of the magnetic fields during erasing and during erasing were reversed. FIG. 7 is a perspective view showing the schematic structure of a conventional information recording device. A disk 1 is set in this information recording device 6 via a vibration isolating material 2 that prevents uneven rotation. Opposed to this disk 1, a bias magnet such as an electromagnet consisting of a yoke and a coil is attached to a predetermined position of a cover plate 5 made of synthetic resin or the like, so that information can be recorded or erased. There is. [Problems to be Solved by the Invention] However, in the conventional device described above, the cover to which the bias magnet is attached is connected to the device itself, so even though the vibration isolating material is provided, As the motor rotates at high speed, its vibrations are easily transmitted to the bias magnet, and due to the influence of other drive mechanisms, it is difficult to accurately maintain a constant distance between the disk surface and the bias magnet required during recording or erasing. There were times when I was unable to do so. For this reason, variations in magnetic flux density occur at erased or recorded positions on the disk surface, often resulting in improper magnetization of recorded bits. In some cases, accurate information was not recorded or erased, and erroneous information was obtained as shown in FIG. FIG. 8 is a diagram for explaining erasure of information. The recorded bits on the disk surface are "1" if they are magnetized diagonally as shown in the figure, and "0" if they are perpendicular.
A digital signal string in units of bits is formed. And the audio information [Shiya] is
Erasing processing is performed using the illustrated bit pattern. Normally, if the distance between the disk and the bias magnet is kept constant (step S1), all

It will be correctly erased as a digital signal sequence of [0], but the distance between the disk and the bias magnet will not be maintained constant (step S2).
As shown in the figure, magnetized bits remain and audio information is reproduced as erroneous information. Therefore, there has been a demand for the development of an information recording device that can perform reliable recording or erasing by always maintaining a constant distance between the disk and the bias magnet. [Embodiments] Hereinafter, specific embodiments of the information recording device of the present invention will be described with reference to the drawings. FIG. 1 is a perspective view showing a schematic structure of an embodiment of the present invention. The information recording device 10, which processes information on a disc-shaped disk at high speed, includes an optical head that detects information and converts it into an electrical signal, a storage, conversion, and playback circuit made into a small module using an IC, and various other components. It is equipped with a servo circuit that controls a servo actuator, and has a structure that allows information to be randomly recorded, reproduced, or erased on the disk surface. Then, the desired disk can be viewed from the outside in either the vertical or horizontal directions V~V' or U~U'.
In order to be installed at a predetermined information detection position 111 of the information recording device 10, the device has a cover 5 made of synthetic resin or the like that can be opened and closed in the vertical direction V to V' or the left and right direction U to U' as shown in the figure. It has a structure in which an attachment/detachment opening 4 is formed. and again,
The above device has a structure in which a mechanism for always maintaining a constant distance between the disk and the bias magnet, which will be described later, is built into the device. FIG. 2 is a perspective view showing the detailed structure and function of the disk up-and-down feeding mechanism and vibration-proofing mechanism according to one embodiment of the present invention. Here, in order to accurately fix the disk 1 in a predetermined position, it is necessary to press the disk 2 on the disk support plate 11 shown in FIG. 4 from above. For this reason, the inner hole 2aa of the disk
A clamp member 44 having an inner diameter that can be brought into close contact with the mounting plate 45 is attached to the mounting plate 45 via a bearing 48 shown in FIG.
is connected to. Also, as shown in the figure, so that the mounting plate 45 can be slid in the vertical direction from V to V',
Drive motors 20a and 20b such as servo motors,
It is equipped with a gear (pinion) 21 and a rack 22. A bias magnet 23 to which an appropriate DC bias magnetic field is applied for recording and reproduction.
is in close contact with a mounting plate 45, facing the disk 1. In the above configuration, its functions will be explained below. When setting the disk 1, align the inner hole 2aa of the disk 1 with the clamp member 44, and simultaneously rotate the motors 20a and 20b in the W direction to rotate the gear 21 and move the rack in the V' direction. Then, the disk is attached to a centering member 4, which will be described later.
9 through the bearing 48 and is set. At the same time as the disk 1 is clamped, the bias magnet 2 attached to the mounting plate 45
3 is brought close to the disk 1 and held stably at a constant distance from the disk surface. In the case of eject, reverse the above, move the motors 20a and 20b.
By rotating in the W′ direction, the disk can be easily ejected. FIG. 3 is a sectional view showing the structure of a disk clamping mechanism according to an embodiment of the present invention. Here, the center of the disc-shaped disk 1 is the rotation axis 47 of the drive motor 41 such as a spindle motor.
The structure is such that it is accurately set at the centers E to E', and no rotational deviation occurs. The disk 1 placed on the disk support plate 11 is brought into close contact with the positioning member 43 so as not to shift in the left and right directions U to U'. Also, disk 1 has upper and lower V~
By using the clamp member 44 and turntable 42 to cope with the vibration in the V' direction,
At points X and Y in the figure, there is a good degree of close contact. Furthermore, at point Z in the figure, the clamp member 44 and the centering member 4
9 are closely engaged with each other in a concave and convex structure, and rotational motion is smoothly transmitted to the clamp member 44 without deviation from the axial centers E to E'. In this case, the disk 1 has a rotation axis E~
It rotates at high speed around E', but since the bearing 48 is press-fitted into the clamp 44 as a buffer, its rotational movement is cut off.
It is not transmitted to the mechanism above the mounting plate 45. Further, the positioning member 43 is normally held in a lifted state by the spring 46, and when attached,
By contracting the spring 46, variations in the disk inner diameter and various parts can be absorbed. In this way, since the clamp member is in direct contact with the disk, the bias magnet, which is connected to and integrally interlocks with the mounting plate 45 attached to this clamp member, always maintains a predetermined distance from the disk 1. It is now possible to record and erase accurate information. FIG. 4 is a perspective view showing the detailed structure and loading function of the disk loading mechanism when the disk 1 is loaded from the loading/unloading port 4. A motor 61 is connected to a gear (pinion) 62, and the gear 62 and a rack 63 fixed to the guide member 57 are configured to mesh with each other. Moreover, the guide member 57
, a guide elongated hole 58 and a disk support plate 1 are provided with a guide elongated hole 58 whose sliding amount in the linear direction in each of the mounting direction U and the removal direction U' is determined according to the length of the hole.
1 by a predetermined sliding amount;
Furthermore, a fixing pin 66 is provided for fixing the disk support plate 11 by a predetermined sliding amount in the vertical V-V′ direction.
is equipped with. The disk support plate 11 has a lightweight double-shaped structure, and has a stable vertical V-shaped structure on its side plate.
To ensure sliding in the V′ direction, as shown,
It has a structure in which S-shaped elongated holes 68 (not shown in the figure, but there are four) with steps are opened. Then, the disk support plate 11 and the guide member 57
are designed to slide together in the U-U' direction. Further, a slide member 64 is provided at a predetermined information detection position of the information recording/reproducing apparatus so that the disk support plate 11 is accurately fixed when it is lowered in the V' direction.
Portions a1 and a2 in the figure are adapted to be engaged with each other and brought into close contact. In the above components, the same number of each element (for example, four in the case of the fixing pin 66) are provided at symmetrical positions in the sliding direction U to U',
Each element is integrated so that the disk support plate 11 can be operated smoothly. The mounting function of these configurations will be explained. The loading direction is the U direction, and a desired disk is currently placed on the disk support plate 11 and is about to be supplied to a predetermined information detection position of the information recording device. In this condition, W1 of motor 61
With the rotation in the direction, the gear 62 and the rack 63 are rotated and moved, and the guide member 57 is rotated in the mounting direction U.
It is guided by the fixing pin 59 and slid straight to a predetermined position. in this case,
The movement of the disk support plate 11 is prevented by the pivotally supported mounting pin 69 in FIG.
1 is stopped. On the other hand, the guide member 57 is slid to the position of the fixing pin 59 by the rotation of the motor 61, and along with this, the disk support plate 11 is moved downward along the S-shaped elongated hole 68.
The end face a2 of the slide member 64 is smoothly moved to V' and fixed to the end face a1 as shown in FIG.
are brought into close contact and fixed, and the mounting operation is completed. 5 and 6 are a perspective view and a front view for explaining the attachment/detachment function of the disk loading mechanism of the information recording apparatus of the present invention. The direction of attachment and detachment is
This is in the U' direction, and a disk for which information has been detected is currently placed on the disk support plate 11, and is about to be returned to the outside of the information recording apparatus for the next information detection. In this state, as shown in FIG. 6, the end surface a1 of the slide member 64 and the fifth
The disk support plate 11, which was fixed in a predetermined position with the mounting pins 69 shown in the figure, is attached to the motor 61 shown in FIG.
With the rotation in the W2 direction, the gear 62 and the rack 63 are rotated and moved, and the guide member 57 is slid linearly by a predetermined amount in the attachment/detachment direction U' while being guided by the fixing pin 59. Along with this, the fixing pin 66 is moved in the T direction in FIG.
It is moved along the long hole 68. On the other hand, the disk support plate 11 is supported by the slide member 64.
Since the movement in the U' direction is prevented, the fixing pin 66 is smoothly moved in the upward direction V along the end surface a1 by the movement height H, and becomes freely slidable in the U' direction. Thereafter, the disk support plate 11 and the guide member 57 are integrated. As the motor 62 rotates, it is accurately guided by the fixed pin 59,
It slides linearly in the attachment/detachment direction U' along the guide elongated hole 58, thus completing the attachment/detachment operation. The attachment/detachment mechanism and operation of the above-mentioned embodiment are as follows:
Although this is a disk method using a disk, a cartridge method using a cartridge containing a disk can also be easily performed using the same information recording device. In the above-described embodiments, an electromagnet is used as the bias magnet, but if an appropriate magnetic flux can be generated for recording or erasing, a permanent magnet or the like can also be easily applied to the information recording device of the present invention. ing. [Effects of the Invention] As described above, according to the information recording device of the present invention,
With a simple and inexpensive structure in which the clamp mechanism and bias magnet are linked, the disk and bias magnet can always be held at a predetermined distance in a well-balanced manner.
This has many advantages in that information can always be recorded and erased accurately and stably.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing a schematic structure of an embodiment of the present invention. FIG. 2 is a perspective view showing the detailed structure and function of the disk vertical feeding mechanism according to one embodiment of the present invention. FIG. 3 is a sectional view showing the structure of a disk clamping mechanism according to an embodiment of the present invention. FIG. 4 is a perspective view showing the detailed structure and mounting function of the disk loading mechanism of the present invention. Fifth
6 are a perspective view and a front view for explaining the attachment/detachment function of the disk loading mechanism of the present invention. FIG. 7 is a perspective view showing the schematic structure of a conventional information recording device. FIG. 8 is a diagram for explaining erasure of information. 1... Disc, 2... Vibration isolating material, 3, 23...
Bias magnet, 4... Attachment/detachment port, 5... Cover,
6... Conventional information recording device, 10... Information recording device of the present invention, 11... Disk support plate, 41...
Drive motor, 42... Turntable, 43...
Positioning member, 44... Clamping member, 45...
Mounting plate, 46... Spring, 47... Rotating shaft, 48...
... Bearing, 49 ... Centering member, 57 ... Guide member, 58 ... Guide elongated hole, 59 ... Fixing pin, 20, 61, 70 ... Motor, 21, 62,
71... Gear, 22, 63, 72... Rack, 6
4...Slide member, 66...Fixing pin, 68...
...Elongated hole, 69...Mounting pin, 100...Position detection circuit, 101...Comparison circuit, 102...Switching circuit, 103...Timer, 104...Amplifier.

Claims (1)

[Claims] 1 Consists of a turntable that rotates a disk-shaped recording medium, a clamp member that clamps the medium to the turntable, a bias magnet that applies a bias magnetic field to the medium, and an optical head that irradiates the medium with a light beam. , in the information recording device for recording information on the medium, the clamp member and the bias magnet are supported by the same mounting member, and the mounting member is moved by a driving means in conjunction with the clamping of the medium. An information recording device characterized in that a bias magnet is held close to a medium and held at a constant interval.