JPH11339425A - Disc cartridge - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simplify the constitution with no need of a magnetic center hub to reduce the size, weight and cost by rotatably mounting a disc retainer on one surface facing a disc in a disc cartridge. SOLUTION: A recess 42 is formed into a disc-facing surface of an upper half 33, a hold plate 43 covering a part of the recess 42 is provided on its entire surface, a mounting part 44 of a disc retainer 41 is loosely mounted in a space defined by the upper half 33 and hold plate 43 and hence can be rotatably mounted in the upper half 33, a shutter is opened, a rotary spindle is inserted in an opened window hole to align a magnetic disc and position the orientation flat, a magnet buried in the top end of the rotary spindle attracts the disc retainer 41 to clamp the magnetic disc and the constitution of the magnetic disc is simplified because of no need of a magnetic center hub.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a disk cartridge for rotatably storing a disk, and more particularly to magneto-optical recording of information by applying a magnetic field from a magnetic head while irradiating a laser beam from an optical head. The present invention also relates to a disk cartridge suitable for rotatably accommodating a magnetic disk whose signal is reproduced by a magnetic head in a timely manner.

[0002]

2. Description of the Related Art As is well known, a magnetic recording / reproducing apparatus using a magnetic layer as a recording medium for information includes a magnetic recording / reproducing apparatus,
There is a magneto-optical recording / reproducing device.

A magnetic recording / reproducing apparatus includes a magnetic recording medium and a magnetic head. The magnetic recording medium travels in a state of contact or non-contact with the magnetic head. A signal is recorded on a magnetic layer, a signal is reproduced by picking up a magnetic signal recorded on a magnetic recording medium at room temperature with a magnetic head, and a magnetic field in an erasing direction is applied from the magnetic head to the magnetic layer at room temperature. To erase the signal. On the other hand, a magneto-optical recording / reproducing apparatus is configured to include a magneto-optical recording medium, an optical head, and a magnetic head or a magnet. While the recording medium is running, a laser beam is irradiated from the optical head to the magneto-optical recording medium to raise the temperature of the magnetic layer to near the Curie temperature or the compensation temperature, while applying a magnetic signal from the magnetic head or the magnet to the heated portion. The signal is recorded by irradiating low-level linearly polarized light along the recording track and detecting the change in the Kerr rotation angle of the reflected light corresponding to the arrangement of the reversed magnetic domains formed in the magnetic layer. Is to be reproduced. Signal erasing is performed by irradiating a laser beam from the optical head to the magneto-optical recording medium to raise the temperature of the magnetic layer to near its Curie temperature or compensation temperature.
This is performed by applying a magnetic field in the erasing direction from a magnetic head or a magnet to the heated portion.

The magnetic layer of a magnetic recording medium, for example, a flexible magnetic disk (floppy disk) or a hard disk is made of γ-Fe ₂ O ₃ powder, Co-containing Fe ₂ O ₃ powder,
Fe ₃ O ₄ powder, Co-containing Fe ₃ O ₄ powder, Fe powder,
A magnetic powder such as a Co powder or an Fe-Ni alloy powder is applied and dried together with a binder and an organic solvent or the like, or a powder of Co, Fe, Ni, a Co-Ni alloy, a Co-Cr alloy,
Co-P alloy, Co-Ni-P alloy, Al-Co alloy,
It is formed of a ferromagnetic material such as an Al-Ni-Co alloy formed by vacuum deposition, and has the advantages of high chemical stability, excellent corrosion resistance, and low cost. Further, the magnetic recording medium has a function of rewriting a previously recorded signal with a new signal by writing a new signal in an area where the signal is recorded, that is, an overwrite function, and has an effective transfer speed of the signal. Has the advantage of being faster. On the other hand, the recording density of the magnetic recording medium is limited by the gap width of the magnetic head, and thus has a disadvantage that the recording density cannot be increased.

On the other hand, the advantages and disadvantages of a magneto-optical recording medium are opposite to those of a magnetic recording medium. Signals are recorded by using a perpendicular magnetization film as a magnetic layer and forming fine inverted magnetic domains, so that high recording is achieved. Although the density can be obtained, the signal cannot be overwritten unless the film structure of the medium and the drive device are specially devised, and the effective transfer speed of the signal as in the magnetic recording / reproducing system cannot be obtained. As a magnetic layer of a magneto-optical recording medium, a rare earth-transition metal-based perpendicular magnetic film is currently considered to be most suitable. However, such a perpendicular magnetic film has low chemical stability and poor corrosion resistance. Another drawback is that the long-term storage of the signal is poor. If the magneto-optical recording / reproducing system is configured to be overwritable, the film structure of the medium and the drive device become complicated, and the system becomes expensive.
Further, in order to improve the corrosion resistance of the magneto-optical recording medium, a number of protective layers must be laminated, which also increases the cost.

[0006]

SUMMARY OF THE INVENTION In an information recording medium and an information recording / reproducing system, a recording capacity is high.
Excellent long-term storage, fast signal transfer speed,
It is particularly required that it can be implemented at low cost.

SUMMARY OF THE INVENTION The present invention has been made to solve such a technical problem, and has as its object to record and reproduce completely new information having the advantages of a magnetic recording / reproducing device and a magneto-optical recording / reproducing device. An object of the present invention is to provide a disk cartridge suitably applied to an apparatus.

[0008]

According to the present invention, in order to achieve the above object, first, in a disk cartridge for rotatably storing a disk, one surface of the disk cartridge facing the disk is provided inside the disk cartridge. The disc holder is rotatably mounted.

When the disk holder is rotatably mounted on the inner surface of the disk cartridge, it is not necessary to provide a magnetic center hub on the magnetic disk, so that the configuration of the magnetic disk is simplified and the recording / reproducing apparatus side is provided. As compared with the case where the clamp member of the magnetic disk is set, the size and weight of the recording / reproducing apparatus can be reduced, and the cost can be reduced.

In order to achieve the above object, the present invention has a second configuration in which a disk cartridge for rotatably storing a disk has an opening / closing structure for replacing the disk.

As described above, when the disk cartridge is configured so that the magnetic disk can be replaced as appropriate, a plurality of magnetic disks can be used with one disk cartridge, so that the storage space for the magnetic disk and the disk cartridge can be reduced. And a large number of magnetic disks can be stored in a storage space of a fixed capacity.

In the disk cartridge, windows for inserting a head may be opened on the disk facing surface, and each of these windows may be provided with a shutter which can be opened and closed independently. In this way, if each shutter can be opened and closed independently, unnecessary windows can be closed.
It is possible to effectively prevent dust from entering the disk cartridge.

In the window, an optical head and a magnetic head disposed opposite to each other can be inserted into different windows,
An optical head and a magnetic head arranged adjacent to each other can be inserted into the same window. According to the latter, the space required for setting the heads can be remarkably reduced as compared with the former, and the mechanism for moving the heads up and down can be significantly simplified.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First, the configuration of a magnetic recording / reproducing apparatus to which a disk cartridge of the present invention is applied and the configuration of a magnetic disk housed in a disk cartridge of the present invention will be described with reference to FIGS. explain. 1 is a configuration diagram of a first magnetic recording / reproducing apparatus, FIG. 2 is an enlarged cross-sectional view of a main part of FIG. 1, and FIGS. 3 to 9 are cross-sectional views illustrating a film structure of a magnetic disk.

As shown in FIGS. 1 and 2, a first magnetic recording / reproducing apparatus comprises a magnetic disk 1, an optical head 2 arranged on one side of the magnetic disk 1,
And the magnetic head 3 arranged on the opposite side through the optical head 2. As the optical head 2,
Except that an optical system for signal reproduction is not required, those conventionally applied to optical disk systems can be used as they are. As the magnetic head 3, a magnetic head conventionally applied to a magnetic recording / reproducing system can be used as it is. However, in the present apparatus, the track width can be set to a micron order or a submicron order, and accordingly, a smaller gap width is more preferable.

As the magnetic disk 1, those as exemplified in FIGS. 3 to 9 can be used.

The magnetic disk 1 shown in FIG. 3 has a preformat pattern such as a guide groove 11 for tracking the optical head 2 and the magnetic head 3 on one side and a prepit 12 for optically reading the address and the like of a recording area. A transparent water-permeable prevention film 14 and a transparent heat-insulating film 15
And a light-reflective magnetic film 16 are laminated in this order.
As the transparent substrate material, a resin material such as polycarbonate or polymethyl methacrylate is particularly suitable. As the transparent water-permeation preventing film 14, an inorganic material such as SiO ₂ is particularly suitable. As the transparent heat insulating film 15, SiN
Alternatively, an inorganic material such as a mixture of SiO ₂ and SiN is particularly suitable. As the magnetic film 16, (1) γ-Fe ₂
O ₃ powder, Co-containing Fe ₂ O ₃ powder, Fe ₃ O ₄ powder,
Co-containing Fe ₃ O ₄ powder, Fe powder, Co powder, Fe-
A magnetic powder such as a Ni alloy powder applied and dried together with a binder and an organic solvent, and (2) Co, Fe, Ni,
Co-Ni alloy, Co-Cr alloy, Co-P alloy, Co
-Ferromagnetic materials such as -Ni-P alloy, Al-Co alloy, Al-Ni-Co alloy formed by vacuum film formation; (3) Tb,
Rare earth elements such as Dy, Gd, Hf and Co, Fe, N
A spontaneously magnetized ferromagnetic perpendicular magnetic film made of an amorphous alloy mainly containing a transition element such as i or Cr can be used. If necessary, a lubricating protective film made of a mixed solution of a resin adhesive such as epoxy and a lubricant such as alumina or carbon (graphite powder) can be applied on the magnetic film 16.

In the magnetic disk 1 shown in FIG. 4, a transparent water-permeable prevention film 14, a transparent heat-insulating film 15, and a reflective film 17 are formed on the same pre-format pattern forming surface of the transparent substrate 13 as described above.
And the magnetic film 16 are laminated in this order. As a reflective film material, alumite, aluminum whose surface is only anodized, or Ti
-Al and the like are particularly preferred. For others, see Figure 3.
The description is omitted to avoid duplication.

The magnetic disk 1 shown in FIG. 5 is formed by laminating a reflective film 17 and a magnetic film 16 on a preformat pattern forming surface of a transparent substrate 13 in this order. Materials and the like suitable for each part are the same as those in the embodiment of FIG. 4, and therefore, description thereof will be omitted to avoid duplication.

In the magnetic disk 1 shown in FIG. 6, a transparent water-permeable preventing film 14, a reflecting film 17, a magnetic film 16, a lubricating protective film 18 Are laminated in this order. As described above, a mixed solution of a resin adhesive such as epoxy and a lubricant such as alumina or carbon can be used as the lubricating protective film material. For others, see FIG.
The description is omitted to avoid duplication.

In the magnetic disk 1 shown in FIG. 7, a transparent water-permeable preventing film 14, a magnetic film 16 and a reflective film 17 are laminated in this order on the same pre-format pattern forming surface of the transparent substrate 13 as described above. Become. For materials suitable for each part,
Since it is the same as the embodiment of FIG. 4, description will be omitted to avoid duplication.

In the magnetic disk 1 shown in FIG. 8, a transparent water-permeable preventing film 14, a light-to-heat converting layer 19, and a magnetic film 16
And the reflection film 17 are laminated in this order. Examples of the light-heat conversion layer material include organic dye materials such as cyanine dyes and phthalocyanine dyes, Te, Bi, Te-Se-Pb alloys,
A thin film such as an Au-Sn alloy can be used.
The other parts are the same as those in the embodiment of FIG. 4, and the description thereof will be omitted to avoid duplication.

In the magnetic disk 1 shown in FIG. 9, a transparent water-permeable prevention film 14, a transparent light-to-heat conversion layer 19, a reflection film 17, a magnetic film 16 And the protective film 18 are laminated in this order. Materials and the like suitable for each part are the same as those in the embodiment of FIG. 8, and therefore description thereof is omitted to avoid duplication.

As shown in FIG. 1, the magnetic disk 1 shown in FIGS. 3 to 9 is formed in a disk shape having a spindle hole 1a opened in the center. The guide groove 11 is formed in a spiral or concentric shape concentric with the spindle hole 1a. Pre-pit 1
2 is formed on the guide groove 11 or on a land between adjacent guide grooves. In this example, a preformat signal such as an address signal is recorded on the transparent substrate 13 in the form of the prepits 12, but it is of course possible to record it on the magnetic film 16 in the form of a magnetic signal.

As shown in FIG. 1, the magnetic disk 1 is mounted on a turntable 5 which is a medium drive unit of a drive device by inserting a tip of a rotary spindle 4 into a spindle hole 1a. The optical head 2 is provided on the transparent substrate side of the magnetic disk 1, and the magnetic head 3 is provided on the magnetic film 16 side of the magnetic disk 1. The distance between the disk surface of the magnetic disk 1 and the optical head 2, the contact pressure between the disk surface of the magnetic disk 1 and the magnetic head 3, and the relative position of the optical head 2 and the magnetic head 3 are determined by the magnetic disk 1. When mounted on the turntable 5, it is mechanically adjusted to a predetermined value. That is, the distance between the disk surface and the optical head 2 is adjusted near the focal length of the optical head 2, and the distance between the disk surface and the magnetic head 3 is adjusted.
Is adjusted to a predetermined value by a gimbal spring (not shown) on which the magnetic head 3 is mounted. Also,
The optical head 2 and the magnetic head 3 are positioned so that the gap of the magnetic head 3 is arranged on the optical axis of the optical head 2. The optical head 2 and the magnetic head 3 are integrally attached to a head frame 73, and are transported by the same amount in the same direction according to the rotation amount and the rotation direction of the feed screw 70 driven to rotate by the motor 72. . The motor 72 is controlled by a head feed control signal transmitted from a control device (not shown). Signal exchange between the optical head 2 or the magnetic head 3 and a controller (not shown) is performed via a signal controller 74. As shown in FIGS. 1 and 2, the magnetic recording / reproducing apparatus of the present embodiment irradiates a laser beam 6 from an optical head 2 along a guide groove (not shown) of a magnetic recording medium 1, and generates a tracking error based on the reflected light. The optical head 2 and the magnetic head 3 are tracked by obtaining a signal, and a desired information recording area is irradiated with a laser beam of a constant intensity for raising the temperature of the magnetic layer 16 from the optical head 2 while the magnetic head 3 is heated. By applying a pulse-like magnetic signal larger than the coercive force of the magnetic layer 16 to the magnetic layer 16, information can be recorded. During recording, it is ideal that the temperature of the magnetic layer 16 be raised to near the Curie temperature or the compensation temperature.
6, the magnetic signal strength required for recording information can be reduced as compared with the case where recording is performed at room temperature as in a normal magnetic disk. This is effective in lowering the output and increasing the recording capacity of the magnetic recording medium 1.

In reproducing information, the magnetic head 3 is positioned at a desired information recording area while tracking the optical head 2 and the magnetic head 3 by the above-described method, and a signal from the area is magnetically read. Can be done with

To erase information, the optical head 2
Then, while tracking the magnetic head 3 and irradiating a desired information recording area with a laser beam of a constant intensity for raising the temperature of the magnetic layer 16 from the optical head 2, the coercive force of the magnetic layer 16 when the temperature is raised from the magnetic head 3 This can be performed by applying a magnetic signal in a large erasing direction to the magnetic layer 16.

Next, the configuration of the second magnetic recording / reproducing apparatus is as follows.
This will be described with reference to FIGS. As shown in FIG. 10, in the magnetic recording / reproducing apparatus of this example, first and second magnets 21 and 22 having polarities opposite to each other are arranged on the magnetic layer 16 forming surface side via the magnetic disk 1. Along with
The magnet 21 on the opposite side via the magnetic disk 1,
First and second optical heads (objective lenses) 2a and 2b are disposed at positions opposing to each other, and a magnetic head 3 is disposed outside the positions where the first and second magnets are disposed. Do it. In FIG. 10, 23 is a laser light source, 2
4 is a beam splitter, 25 is a mirror, 26 is an optical modulator. Laser beam 6 emitted from laser light source 23
Is divided into two by the beam splitter 24. One of the split laser beams 6 is
The first optical head 2a is guided to a first objective lens optical head 2a arranged on the upstream side in the rotation direction of the magnetic disk 1, and is irradiated on the magnetic disk 1 as initialization light having a constant intensity from the first optical head 2a. The other of the split laser beams 6 is guided to an optical modulator 26 by a beam splitter 24, and intensity-modulated in a pulse shape by a predetermined information signal. The modulated light output from the optical modulator 26 is transmitted to the second optical head 2 disposed downstream of the magnetic disk 1 in the rotation direction.
b, and is emitted to the magnetic disk 1 as recording light from the second optical head 2b.

As the magnetic disk 1, those exemplified in FIGS. 3 to 9 described above can be used.

As the magnets 21 and 22, those having a magnetic field strength capable of applying a magnetic field larger than the coercive force of the magnetic film 16 to the magnetic film 16 when the temperature is raised are used. Specifically, (1) Co, Fe, Ni, Co-Ni
Alloy, Co-Cr alloy, Co-P alloy, Co-Ni-P
Alloys, Al-Co alloys, Al-Ni-Co alloys, etc., formed into strips and vertically magnetized; (2) γ-Fe ₂ O ₃
Powder, Co-containing Fe ₂ O ₃ powder, Fe ₃ O ₄ powder, Co
Fe ₃ O ₄ powder, Fe powder, Co powder, Fe-Ni
Magnetic powder, such as alloy powder, coated with a binder and an organic solvent, dried and perpendicularly magnetized; (3) Co, F
e, Ni, Co-Ni alloy, Co-Cr alloy, Co-P
Alloy, Co-Ni-P alloy, Al-Co alloy, Al-N
(4) Tb-Fe-Co alloy, Tb-Fe-Co- ferromagnetic material such as an i-Co alloy formed by vacuum deposition using a vacuum deposition method or a sputtering method and then perpendicularly magnetized.
Cr alloy, Tb-Fe-Co-Nb alloy, Gd-Dy-
Spontaneously magnetized ferromagnetic perpendicular magnetization films made of amorphous alloys mainly containing rare earth elements and transition elements, such as Fe-Co alloys, Tb-Gd-Fe-Co-Cr alloys, (5)
A spontaneously magnetized ferromagnetic perpendicular magnetization film similar to that described in (6) may be used in which the outer surface is coated with a corrosion-resistant material such as Ni, Co, or Cr. Among them, (2), (3), (4), (5)
Are particularly preferred.

The magnets 21 and 22 are respectively set in a band shape along the radial direction of the magnetic disk 1. Its width is
From micron order or submicron order to 50
Although it can be set to an arbitrary value up to the order of mm, preferably, the optical heads 2a and 2b and the magnets 21 and 2 when the magnetic disk 1 is mounted on the drive device.
The width is set to be larger than a value obtained by adding the variation width to the deviation width of the laser beam 6 from the length of the minimum magnetization domain to the deviation width. Further, the lengths of the magnets 21 and 22 are formed so as to cover at least the recording area of the magnetic disk 1. The magnets 21 and 22 do not necessarily need to be formed in a continuous shape, and may be fine magnets 21 and 22 arranged in a straight line. In this case, the length of each of the fine magnets 21 and 22 can be larger than the track pitch.

The magnets 21 and 22 are preferably arranged as close as possible to the disk surface, so that the surfaces of the magnets 21 and 22 are opposed to the disk surface at a desired narrow interval when the disk rotates. The height of the magnet mount 27 or the thickness (film thickness) of the magnets 21 and 22 is adjusted for use. The magnetic disk 1
The surface facing the magnet is coated with a film having excellent smooth wear resistance and heat resistance, and a film having excellent slip and wear resistance is formed on the surfaces of the magnets 21 and 22, and these films are formed. The magnets 21 and 22 can be brought into sliding contact with the disk surface via the intermediary.

The magnetic recording / reproducing apparatus of the present embodiment employs an optical head 2
a, a laser beam of a signal reproduction level is radiated along the guide groove 11 of the magnetic disk 1 and a tracking error signal is obtained from the reflected light to perform tracking of the optical heads 2a and 2b. The magnetic layer 16 is required to lower the coercive force of the magnetic layer 16 below the magnetic field intensity applied from the first magnet 21 at a portion facing the first magnet 21 disposed on the upstream side in the rotation direction of the magnetic disk 1. Laser beam of constant intensity and size (Fig. 1
1 is radiated from the optical head 2a to initialize the magnetic layer 16 in that portion.
The laser beam emitted from the magnetic layer 16 is positioned on the initialized track and at a portion facing the second magnet 22 disposed on the downstream side in the rotation direction of the magnetic disk 1 so as to reduce the coercive force of the magnetic layer 16. The laser beam modulated in intensity into a pulse having a magnitude necessary for lowering the magnetic field intensity applied from the second magnet 22 to the optical head 2b
Information can be recorded by irradiating from. That is, the second
The direction of magnetization of the magnet 22 is the first magnet 2
The magnetic field strength of the second magnet 22 is opposite to the direction of magnetization of the first magnet 22 and is adjusted to a magnitude capable of applying a magnetic field larger than the coercive force of the magnetic film 16 to the magnetic film 16 when the temperature is raised. Therefore, the temperature-raising portion (the portion irradiated with the high-level laser beam in the laser beam irradiation pattern shown by the broken line in FIG. 11) by the second optical head 2b is selectively turned on by the second magnet 22. The direction of the magnetization is reversed, and a signal is recorded on the magnetic film 16.

Reproduction of information can be performed by positioning the magnetic head 3 in a desired information recording area while tracking the magnetic head 3 by the above-described method, and magnetically reading out signals from the area.

Further, the information is erased by tracking the optical head 2a by the above-described method while facing the first magnet 21 disposed in the desired information recording area and upstream of the magnetic disk 1 in the rotation direction. This can be achieved by irradiating a laser beam of a constant intensity required to reduce the coercive force of the magnetic layer 16 below the magnetic field intensity applied from the first magnet 21 from the optical head 2a.

The magnetic recording / reproducing apparatus of the present embodiment does not require precise alignment between the optical head and the magnetic head, and thus is easier to assemble than the magnetic recording / reproducing apparatus of the first embodiment. There is.

In the example of FIG. 10, two optical heads 2 are used.
Although the optical heads a and 2b are used, as shown in FIG. 12, one optical head 2 is disposed almost in the middle of the two magnets 21 and 22, and the portion facing the first magnet 21 from the optical head and the The part facing the second magnet 22 is
The laser beams 6a and 6b may be irradiated. That is, the laser beam 6 emitted from the laser light source 23 is split into two by the beam splitter 24, one of which is directly incident on the optical head 2 via the mirror 25, and the other is incident on the optical head 2 via the optical modulator 26. Incident. In this way, a laser beam having a constant intensity and a laser beam whose intensity is modulated can be emitted together from one optical head (objective lens) 2.

Hereinafter, a configuration example of the disk cartridge according to the present invention will be described with reference to FIGS.

FIGS. 13 and 14 are views showing the first embodiment. FIG. 13 is a cross-sectional view in which the upper and lower parts are inverted, and FIG. 14 is a perspective view in which the upper and lower parts are inverted and partly cut away. In these figures, reference numeral 31 denotes a disk cartridge, and other parts corresponding to the above-mentioned respective figures are denoted by the same reference numerals. The disk cartridge 31 includes a lower half 32, an upper half 33, a magnetic disk 1 rotatably housed in a space formed by joining these two halves 32, 33, a lower half 32 and an upper half 3.
3, a shutter 34 slidably mounted along one side of the joined body, a magnet mount 27 provided on the inner surface of the upper half 33, and a magnet 21 provided on the surface of the magnet mount 27. , 22 mainly.

Each of the lower half 32 and the upper half 33 is formed in a shallow dish shape in which a joining wall 36 having a constant height is raised along three sides except the periphery on the side where the shutter 34 is mounted. A shutter 34 is provided on the inner surface of the side portion on the mounting side.
A guide projection 37 for attaching a slider 35 fixed integrally with the slider 35 and slidably holding the slider 35 is formed. The height of the guide projection 37 is lower than the height of the joining wall 36. When viewed from the side of the shutter mounting side, a window hole 38 is formed in the center of the lower half 32, extending from the vicinity of the guide projection forming side to the vicinity of the opposing periphery. A rotary spindle 4 for rotatingly driving the magnetic disk 1 through the hole 38, an optical head 2 for irradiating the magnetic disk 1 with a laser beam, and a magnetic head 3 for reading signals from the magnetic disk 1
Can be inserted. On the other hand, a magnet mounting base 27 is integrally provided in a portion extending from a substantially central part of the inner surface of the upper half 33 to a vicinity of the periphery on the guide projection forming side, and a magnet 2 is provided on the surface of the magnet mounting base 27.
1 and 22 are provided.

The lower half 32 and the upper half 33 are made of, for example, ABS resin, AS resin, vinyl chloride resin, polypropylene resin, polycarbonate resin, polyacrylate resin, polymethyl methacrylate resin, polytetrafluoroethylene resin, and these resin materials. It can be formed by using a material mixed with filler or carbon. The magnet mount 27 can be attached to the upper half 33 separately from the upper half 33. However, it is preferable that the magnet mount 27 be integrally formed with the upper half 33 for ease of manufacture.

The shutter 34 is formed in a flat plate shape capable of opening and closing a window hole 38, and a slider 35 for operating the shutter 34 from outside is attached to one end thereof. The slider 35 is formed with two concave grooves 39a and 39b in which the guide projections 37 formed on the lower half 32 and the upper half 33 can be gently inserted.
The shutter 34 is housed in the disk cartridge 31,
Further, by inserting the guide projections 37 into the concave grooves 39a and 39b, the combined body of the shutter 34 and the slider 35 is slidably attached to the disk cartridge 31, and the shutter 34 is slidable on the inner surface of the lower half 32. Is set to

A return spring (not shown) is stretched between the shutter 34 or the slider 35 and the lower half 32. Therefore, as long as the slider 35 is not operated from the outside, the window hole 38 is closed by the shutter 34, and entry of foreign matter such as dust is prevented. When the shutter 34 is driven in the opening direction against the elastic force of the return spring, the window hole 38 is opened, and the rotary spindle 4, the optical head 2, and the magnetic head 3 can be inserted into the disk cartridge 31. .

The shutter 34 and the slider 35 are
It can be formed using a resin material, a ceramic material, a metal material (particularly, stainless steel), or the like. Although the shutter 34 and the slider 35 can be mechanically connected to each other formed separately, it is more preferable that the shutter 34 and the slider 35 be integrally formed to facilitate manufacture.

In the disk cartridge of this embodiment, since the magnetic disk 1 is housed in the disk cartridge 31 and the magnets 21 and 22 are set on the inner surface of the disk cartridge 31, members for setting the magnets 21 and 22 are separately required. And the design of the system is easy. Also, optical heads 2 are provided on both sides thereof through a spindle hole 1a.
And the magnetic head 3, the recording or erasing of the signal by the optical head 2 and the magnets 21 and 22 and the reproduction of the signal by the magnetic head 3 can be simultaneously and independently performed, and the effective transfer of the signal is performed. It has the feature of high speed.

Next, a disk cartridge according to a second embodiment will be described with reference to FIGS. FIG. 15 is an exploded perspective view of the disk cartridge according to this embodiment, and FIG.
Is a perspective view seen from below, and FIGS. 17 to 19 are explanatory views of the disc holder. 15 and FIG.
Indicates a disc retainer, and other portions corresponding to the respective drawings described above are denoted by the same reference numerals.

As shown in FIGS. 15 and 16, in the magnetic recording / reproducing system of this embodiment, a disk holder 41 is provided at the center of the inner surface of the upper half 33, and the optical head 2 and the magnetic head 3 are adjacent to each other. It is characterized by having been set.
The disk holder 41 is formed on a disk having a diameter substantially equal to that of the turntable 5 using a material having at least a disk-facing surface provided with magnetism, and is rotatably attached to the center of the inner surface of the upper half 33.

As shown in FIG. 17, the disc holder 41 has a recess 42 formed in the disc-facing surface of the upper half 33 and a holding plate 43 for covering a part of the recess 42 on the front surface thereof. The mounting portion 44 of the disc holder 41 is gently provided in the space defined by the upper half 33 and the holding plate 43, so that the disk holder 41 can be rotatably mounted on the upper half 33. As shown in FIG. 18, a through hole 45 having a diameter smaller than the diameter of the disc holder 41 is formed in the upper half 33, and a shutter mounting groove 46 is formed in the disc holder 41. Can be rotatably attached to the upper half 33. FIG.
In FIG. 18 and FIG. 18, reference numeral 47 in the figure denotes a ferromagnetic plate. Further, as shown in FIG. 19, a concave portion 42 is formed on the outer surface of the upper half 33, and a holding plate 43 that covers a part of the concave portion 42 is provided on the surface thereof. By loosely mounting the mounting portion 44 of the disc holder 41 in the space defined by 43,
It can be rotatably attached to the upper half 33. In FIG. 19, reference numeral 48 in the figure indicates a magnet.

In this embodiment, the optical head 2 and the magnetic head 3 are set adjacent to each other. Therefore, it is sufficient to form the window hole 38 in the lower half 32 only in a portion extending from the substantially central portion to the vicinity of the periphery on the guide projection forming side. Other configurations are the same as those of the above-described embodiments. Therefore, the same reference numerals are given to portions corresponding to the drawings representing the respective embodiments, and description thereof is omitted.

In the disk cartridge of this embodiment, the shutter 3b is opened, and the rotary spindle 4 is opened through the opened window hole 38.
Is inserted, the rotary spindle 4 is inserted into the spindle hole 1a opened in the center of the magnetic disk 1, and the magnetic disk 1 is centered. The magnetic disk 1 is placed on the turntable 5, and the magnetic disk 1 is positioned in the surface direction. When this stage is reached, a magnet (not shown) embedded in the tip of the rotary spindle 4 attracts the disk presser 41, and the magnetic disk 1 is clamped by the attraction force. Therefore,
In the disk cartridge of the present embodiment, it is not necessary to provide a magnetic center hub on the magnetic disk 1. Therefore, the configuration of the magnetic disk 1 is simplified, and when the clamp member of the magnetic disk 1 is set on the recording / reproducing apparatus side. Compared to,
The recording / reproducing device can be reduced in size, weight, and cost. Further, in the case of this example, the optical head 2 and the magnetic head 3 are set adjacent to each other, so that the optical head 2 and the magnetic head 3 are set on the upper and lower sides of the magnetic disk 1 via the magnetic disk 1. Thus, the space required for setting the heads can be significantly reduced, and the mechanism for moving the heads up and down can be significantly simplified.

Next, the structure of the disk cartridge according to the third embodiment will be described with reference to FIGS. FIG. 20 is a sectional view of the disc cartridge according to the present embodiment, and FIG.
1 is an exploded perspective view, and FIG. 22 is a perspective view seen from below the upper half. In these figures, reference numeral 51 indicates a center hub, and other parts corresponding to the above-mentioned respective figures are denoted by the same reference numerals.

As shown in FIGS. 20 and 21, the disk cartridge of this embodiment has a magnetic center hub 51 set at the center of the magnetic disk 1 and a lower half 32.
A first window hole 38a for inserting the rotary spindle and the optical head 2 is formed in a portion extending from a substantially central portion to a portion near the periphery of the guide projection forming side, and the first window hole 38a is inserted through the central portion of the upper half 33. A second window hole 38b for inserting the magnetic head 3 is provided on the side symmetrical to the first window hole 38a. On the outer surface of the lower half 32 and the outer surface of the upper half 33, shutters 34a, 3
4b, magnets 21 and 22 are provided on a portion of the inner surface of the upper half 33 facing the first window hole 38a. In the disk cartridge of the present example, the transparent substrate 13 is oriented toward the optical head 2 and the magnetic layer 16
The disc cartridge 31 is housed in the drive device such that the disc cartridge 31 is directed toward the magnets 21 and 22 and the magnetic head 3.

Next, the structure of the disk cartridge according to the fourth embodiment will be described with reference to FIGS. FIG. 23 is a perspective view of the disc cartridge according to the present embodiment in an open state, FIG. 24 is a perspective view seen from below at the time of assembly, and FIG. 25 is a sectional view at the time of assembly. In these figures, parts corresponding to the above-mentioned figures are denoted by the same reference numerals.

As shown in FIGS. 23 and 24, the disk cartridge of this embodiment is characterized in that the disk cartridge 31 is configured to be openable and closable, so that the magnetic disks housed in the disk cartridge 31 can be replaced as appropriate. And On the inner surface of the lower half 32, a disk storage unit 6 is provided.
1 is recessed in a substantially circular shape, and the magnetic disk 1 has a disk holding portion 6 protruding from an outer peripheral portion of the disk storage portion 61.
2 is held. The left and right end portions 60a and 60b of the disk storage portion 61 are open to the side surfaces of the lower half 32, and the magnetic disk 1 can be easily grasped by putting fingers in the lower half 32. A window 38 for inserting a head and a rotary spindle extending in the radial direction of the magnetic disk 1 is opened in a part of the lower half 32, and a shutter for opening and closing the window 38 is provided on an outer surface of the lower half 32. 34 are applied. In addition,
Reference numeral 63 in FIGS. 24 and 25 indicates a shallow recess for accommodating the shutter 34. On the other hand, upper half 33
A disc holder 41 is provided at a central portion of the inner surface of the device, and magnets 21 and 22 are provided at a portion facing the window hole 38. As the disc holder 41, the same one as shown in FIGS. 17 to 19 can be used. In the disk cartridge of this example,
By inserting an optical head and a magnetic head through one window hole 38, information can be recorded, reproduced, and erased.

In the disk cartridge of this embodiment, the lower half 32 and the upper half 33 are configured to be openable and closable so that the magnetic disk 1 can be replaced as needed. can do. Therefore, the storage space for the magnetic disk 1 and the disk cartridge 31 can be reduced, and
A large number of magnetic disks 1 can be stored in a storage space of a fixed capacity.

Next, the structure of the disk cartridge according to the fifth embodiment will be described with reference to FIGS. 26 and 27.
FIG. 26 is an exploded perspective view of the disk cartridge according to this example, and FIG. 27 is a sectional view. In these figures, parts corresponding to the above-mentioned figures are denoted by the same reference numerals. The disc cartridge of this embodiment is characterized in that double-sided recording can be performed.

The disk cartridge 31 of this embodiment is similar to that of FIG.
As shown in FIG. 6 and FIG. 27, windows 18a and 18b of the same shape and the same size are opened at the opposing positions of the lower half 32 and the upper half 33, and the inner surfaces of the lower half 32 and the upper half 33 are independently formed. Openable and closable shutters 34a and 34b are provided. Disk holders 41a and 41b similar to those shown in FIGS. 17 to 19 are rotatably attached to portions of the inner surfaces of the shutters 34a and 34b corresponding to the center of the disk. Two portions of magnets 22a, 23a, 22b, and 23b are attached to portions corresponding to the movement range (omitted), respectively.

The disk cartridge 31 of this embodiment is the same as that shown in FIG.
As shown in FIG. 7, when the lower shutter 34b is opened and the rotary spindle 4 is inserted through the opened window hole 38b, the rotary spindle 4 is inserted into the spindle hole 1a opened at the center of the magnetic disk 1, and Centering of the disk 1 is performed. The magnetic disk 1 is a turntable 5
The magnetic disk 1 is placed on the magnetic disk 1 and positioned in the surface direction of the magnetic disk 1. When this stage is reached, the magnet 66 embedded at the tip of the rotary spindle 4 sucks the disk holder 41a, and the magnetic disk 1 is clamped by the attraction force. Therefore, by inserting the optical head 2 and the magnetic head 3 through the opened window hole 38b on the lower side, information can be recorded, reproduced, and erased on the lower surface of the double-sided recording type magnetic disk 1. If the magnetic disk is turned upside down and mounted on the rotating spindle 4,
In the same manner as described above, information recording, reproduction, and erasing operations on the other surface of the double-sided recording type magnetic disk 1 can be performed.

[0059]

According to the first, third, fourth and fifth aspects of the present invention,
Since the disk holder is rotatably mounted on the inner surface of the disk cartridge, there is no need to provide a magnetic center hub on the magnetic disk. This simplifies the configuration of the magnetic disk and clamps the magnetic disk on the recording / reproducing device. Compared with the case where members are set, the size and weight of the recording / reproducing apparatus can be reduced and the cost can be reduced.

According to the second, third, fourth, and fifth aspects of the present invention, since the disk cartridge is configured so that the magnetic disks can be replaced as appropriate, a plurality of magnetic disks can be used with one disk cartridge. The storage space for magnetic disks and disk cartridges can be reduced, and a large number of magnetic disks can be stored in a storage space of a fixed capacity.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of a configuration of a first magnetic recording / reproducing apparatus.

FIG. 2 is an enlarged sectional view of a main part of FIG.

FIG. 3 is a cross-sectional view illustrating a film structure of a magnetic disk.

FIG. 4 is a cross-sectional view illustrating a film structure of a magnetic disk.

FIG. 5 is a cross-sectional view illustrating a film structure of a magnetic disk.

FIG. 6 is a cross-sectional view illustrating a film structure of a magnetic disk.

FIG. 7 is a cross-sectional view illustrating a film structure of a magnetic disk.

FIG. 8 is a cross-sectional view illustrating a film structure of a magnetic disk.

FIG. 9 is a cross-sectional view illustrating a film structure of a magnetic disk.

FIG. 10 is a diagram illustrating the configuration of a second magnetic recording / reproducing apparatus.

FIG. 11 is a graph showing an irradiation pattern of a laser beam.

FIG. 12 is a configuration explanatory view showing a modified example of the second magnetic recording / reproducing device.

FIG. 13 is a cross-sectional view illustrating a first example of a disk cartridge, which is turned upside down.

14 is a partially broken perspective view of the disk cartridge of FIG.

FIG. 15 is an exploded perspective view showing a second example of the disk cartridge.

16 is a perspective view of the disc cartridge of FIG. 15 as viewed from below.

FIG. 17 is a cross-sectional view showing a first example of a disc holder.

FIG. 18 is a cross-sectional view showing a second example of the disc holder.

FIG. 19 is a cross-sectional view showing a third example of the disc holder.

FIG. 20 is a sectional view showing a third example of the disk cartridge.

21 is an exploded perspective view of the disk cartridge of FIG.

FIG. 22 is a perspective view of the upper half as viewed from below.

FIG. 23 is a perspective view showing a fourth example of the disc cartridge when it is developed.

24 is a perspective view of the disk cartridge of FIG. 23 as viewed from below.

FIG. 25 is a sectional view of the disc cartridge of FIG. 23;

FIG. 26 is an exploded perspective view showing a fifth example of the disk cartridge.

FIG. 27 is a sectional view of the disc cartridge of FIG. 26;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Magnetic disk 2 Optical head 3 Magnetic head 4 Rotating spindle 5 Turntable 6 Laser beam 11 Guide groove 12 Prepit 13 Transparent substrate 14 Water permeability prevention film 15 Thermal insulation film 16 Magnetic film 17 Reflection film 18 Protective film 19 Light-to-heat conversion film 21, 22 Magnet 27 Magnet mounting base 31 Disk cartridge

Claims (5)

[Claims] 1. A disk cartridge for rotatably storing a disk, wherein a disk holder is rotatably mounted on one surface of the disk cartridge facing the disk inside the disk cartridge. 2. A disk cartridge for rotatably storing a disk, wherein the disk cartridge has an opening / closing structure for replacing the disk. 3. The disk cartridge according to claim 1, wherein windows for inserting a head are respectively opened on two surfaces facing the disk, and shutters which can be opened and closed independently of each other are provided on each of these windows. A disk cartridge characterized by the above-mentioned. 4. The disk cartridge according to claim 3, wherein an optical head and a magnetic head disposed opposite to each other are inserted into the window. 5. The disk cartridge according to claim 3, wherein an optical head and a magnetic head disposed adjacent to each other are inserted into the window.