JP2000123521A - Disk cartridge - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the signal recording surface of an optical disk from being scratched by preventing it that the optical disk is floated up to be incliningly moved and abutted on a disk case even when the disk receives a dropping shock in the disk cartridge provided with a disk case housing the optical disk and an outer case in which the disk case is to be loaded. SOLUTION: An optical disk 1 having a hub 6 at the under surface of a disk main body 5 is housed in the inside of a disk case 2. Then, the hub 6 of the disk 1 is received with the hub hole 14 of the disk case 2 and, moreover, the hub 6 is pushed down with a spring 15 to be energized and the disk 1 at the time of nonuse is positioned and held. A holding protrusion 20 preventing the inclined movement of the disk 1 is projectingly provided annularly at the periphery of the hub 6 confronted with the peripheral wall of the opening of the hub hole 14.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a disk cartridge in which a disk represented by a magneto-optical disk or a phase change optical disk is incorporated in a disk case.

[0002]

2. Description of the Related Art For example, various disk cartridges are distributed as backup or storage of a large amount of computer data or as an information recording medium for distributing audio and video information, and the signal recording capacity thereof is gradually increasing. It tends to increase. Optical disk cartridges such as MOs and PDs have a storage capacity of 230 to 640 megabytes, and DVDs have a storage capacity of about 5 gigabytes.

[0003]

The improvement in the recording capacity as described above has been realized by increasing the signal recording density. For example, the track pitch is reduced and the pit length is further reduced to improve the signal recording density. As the signal recording density is improved in this manner, a read / write error that can be ignored until then may be recognized as an unrecoverable burst error. In a next-generation optical disk, which is expected to have a recording capacity of about 10 gigabytes on one side as well as a DVD, a burst error is expected to occur due to slight dirt or damage on the signal recording surface.

In a conventional disk cartridge,
By arranging the optical disk in the cartridge case and closing the signal read / write window provided in the cartridge case with a shutter, it is possible to prevent foreign substances from adhering to the signal recording surface or preventing the signal recording surface from being damaged. In many cases, the shutter can only be opened when loaded in a disk drive for dust and protection.
However, with a small amount of knowledge, the shutter can be easily opened in a non-use state, and in such a case, there is room for adhesion of foreign matter and damage to the signal recording surface.

Therefore, in a next-generation optical disk cartridge, a disk for reading and writing signals is accommodated in a disk case, and then the entire disk case is loaded into an outer case so that the shutter cannot be operated in an unused state. . And in the disc case,
A method of having a shutter for opening and closing the signal reading / writing window, and loading the outer case into the disk drive, pulling out the disk case from the outer case, loading the disk case to a predetermined position, and opening the shutter has been studied. By taking such protective measures, artificial staining or damage of the signal recording surface is temporarily eliminated. However, this is not enough, and care must be taken in handling and care should be taken to prevent the signal recording surface from being damaged due to rough handling.

For example, when the disk cartridge drops from a high place or collides vigorously with another object, the disk tilts or the disk case is bent and deformed by the kinetic inertia force, thereby causing the disk case to deform. The inner wall and the signal recording surface of the optical disk come into contact with each other violently. In particular, the sliding concave portion of the shutter, which must be thinner than other portions, is more likely to bend and deform than other portions. As described above, in the situation where the case wall collides with the signal recording surface, the signal recording surface is damaged by abrasion, or the plastic powder generated by the contact is attached to the signal recording surface. By the way, in the case of the disc, the inner surface of the case is kept constant in thickness, and the outer surface of the shutter needs to be flush with the surface of the case.The sliding area of the shutter is recessed from the surface of the case. The wall thickness of the slide recess must be thinner than other portions.

An object of the present invention is to reliably prevent the disk case from coming into contact with the signal recording surface even when a strong external force is applied due to careless handling or rough handling. Thus, it is possible to prevent the signal recording surface of the disk from being damaged or being stained by the adhesion of the plastic powder, thereby improving the reliability of the disk cartridge. Thus, another object of the present invention is to provide a disk cartridge suitable for an optical disk having a high signal recording density.

[0008]

As shown in FIGS. 1 and 2, a disk cartridge according to the present invention comprises:
Read / write disk 1 having hub 6 on the lower surface of the disk
And a disk case 2 for accommodating the disk 1 in a rotatable state. The disc 1 in the unused state is pressed down and urged by a spring 15 disposed between the hub 6 and the disc case 2, and the hub 6 is received and held by a hub hole 14 provided in the disc case 2. The hub 6 and the hub hole 14 are engaged with each other via the tapered surfaces 6a and 14a having a tapered shape, and the signal recording surface of the disk main body 5 faces the inner surface wall of the disk case 2 via the gap E. Positioning is maintained. One of the peripheral wall of the opening inside the case of the hub hole 14 and the lower surface of the disk 1 facing the peripheral wall of the opening is in contact with the wall surface facing the disk 1.
The holding projection 20 for preventing the tilting of the ring is protruded annularly.

The holding projection 20 is provided on the hub 6 as shown in FIG.
Are formed integrally with the hub 6 around the periphery of the hub. And hub hole 14
A restricting protrusion 21 for receiving the peripheral surface of the holding protrusion 20 and restricting the disk 1 from floating in the radial direction is provided on the peripheral wall of the opening inside the case.

As shown in FIG. 5, the holding projection 20 is annularly protruded from the peripheral wall of the opening inside the case of the hub hole 14, and
May be formed on the lower surface of the disk main body 5 surrounding the peripheral surface of the holding projection 20 so as to restrict the radial movement of the disk 1.

As shown in FIG. 4, the inner surface of the disk case 2 which faces the peripheral edge portion 25 of the disk body 5 comes into contact with the edge portion 25 prior to the other case wall surface, and the signal of the disk body 5 An inclined wall 26 for preventing the recording surface from being damaged is formed. The radial width B of the inclined wall 26 is equal to the radial clearance G between the disk 1 and the disk case 2.
Can be set to twice or more.

[0012]

The hub 6 and the hub hole 14 have tapered surfaces 6a and 14
a, the disc 1 does not tilt in the normal state because the hub 6 is pressed down and biased by the spring 15. However, for example, when the disk cartridge receives a drop impact, the disk 1 tends to float up and tilt from the hub hole 14 against the urging force of the spring 15. However, if the disc 1 slightly tilts,
For example, a disk 1 that is received on a wall facing one side of a peripheral edge of a holding projection 20 provided on a hub 6 and is about to tilt.
, The disc 1 immediately returns to the proper standby posture. Incidentally, in a state in which a part of the peripheral edge of the holding projection 20 is received by the opposing wall surface, that is, in a state where the disc 1 is slightly lifted and tilted, the holding projection 2
Since a return moment having the radius value of the peripheral edge diameter of 0 as the moment arm acts on the disk 1, the disk 1 can be reliably returned even when a larger external force is received. The disc 1 may float up so as to move in parallel with the positioning and holding state,
In this case, at the same time when the external force is released, the disk 1 is returned to the original position by receiving the urging force of the spring 15, and the signal recording surface does not come into contact with the disk case 2.

When the holding projection 20 is provided integrally with the hub 6, several kinds of hubs 6 having different protrusion dimensions are prepared, so that several kinds of different distances between the signal recording surface and the disk case 2 are provided. When configuring the disk cartridge, the disk case 2 can be used as a common component, and the manufacturing cost of the disk cartridge can be reduced accordingly.

According to the disk cartridge having the disk case 2 provided with the regulating protrusions 21, the disk 1 is formed in the hub hole 1.
4. When the user intends to lift and tilt from the
The peripheral surface of the disk 1 is received by the restricting projection 21 so that the disk 1 can be restricted from moving in the radial direction. Further, the disc 1 can be returned to an appropriate standby posture and held by restricting the displacement of the center between the hub 6 and the hub hole 14 when the disc 1 is tilted to return.

When the holding projection 20 is provided on the periphery of the opening of the hub hole 14, similarly to the case where the holding projection is provided on the hub 6, the tilting of the disk 1 is prevented to prevent the signal recording surface from being damaged. it can. Further, the restriction recess 24 formed in the disk main body 5 is received and restricted by the peripheral surface of the holding projection 20 as in the case of the above-described restriction projection 21, so that the disk 1 can be prevented from moving in the radial direction.

When the disk cartridge receives a drop impact or the like, the disk case 2 may be flexed and deformed by a kinetic inertia force. However, if the disk case 2 is slightly bent and deformed, the inclined wall 26 provided on the inner surface thereof comes into contact with the edge portion 25 of the disk 1 prior to the other case wall surface. Therefore, even if the disk case 2 is bent and deformed, the disk 1 tilts along with the deformation of the disk case 2. Therefore, the inner surface of the case does not contact the signal recording surface of the disk 1.

The disk 1 has room to be displaced in the radial direction within the disk case 2 by the clearance G, and even when the disk 1 is displaced by the clearance G,
In order to allow the edge portion 25 to be received by the inclined wall 26, the width dimension B is set to be at least twice the marginal gap dimension G.

[0018]

1 to 3 show a first embodiment of a disk cartridge according to the present invention. In FIG. 2, a disc cartridge comprises a disc-shaped optical disc (disc) 1 from which information signals can be read and written, and an optical disc 1
Are rotatably accommodated, an outer case 3 accommodating the disk case 2 removably, a lock mechanism 4 provided between the outer case 3 and the disk case 2, and the like.

The optical disk 1 comprises a disk body 5 and a hub 6 bonded and fixed to the lower surface of the disk body 5. The disk main body 5 is formed by using a disk in which a signal recording layer and a protective layer are formed on one side of a polycarbonate substrate as a constituent element, and is configured as a single-sided recording type using only one disk, or 2 formed with half the thickness of
It can be configured as a double-sided recording type by laminating two disks. In the signal recording layer, for example, information signals of the magneto-optical recording system are recorded at a high density.

The disc case 2 is formed by joining an upper case 2a and a lower case 2b, each of which is plastically molded, in a lid-to-cover manner, and opens a signal read / write window 7 near one side of the upper and lower cases 2a and 2b. The window 7 can be opened and closed by a slidable shutter 8. The shutter 8 has a pair of main walls 9 for opening and closing the upper and lower signal reading / writing windows 7.
9 and a side wall 10 connecting the side edges of the two main walls 9
And a plastic molded product obtained by integrally molding the above. In order to make the outer surfaces of the upper and lower main walls 9 and 9 flush with the upper and lower surfaces of the disk case 2, the sliding area of the shutter 8 is formed as a thin sliding recess 11 by being recessed. The recess depth of the slide recess 11 is set to be equal to or slightly larger than the wall thickness dimension of the main wall 9. The shutter 8 is closed and biased by a spring 12 built in the disk case 2 without permission.

In FIG. 1, a hub hole 14 for receiving and holding the hub 6 is opened at the center of the lower surface of the lower case 2b constituting the disk case 2. Hub 6 and hub hole 1
4 is engaged with the lower tapered surface 6a, 14a. Further, the entire optical disc 1 is urged down by a compression coil type spring 15 disposed between the hub 6 and the upper case 2a. Therefore, the optical disc 1 when not in use is positioned and held concentrically with the hub hole 14 and in a state where the disc main body 5 faces the inner wall of the lower case 2b in parallel with a small gap E therebetween. That is, the urging force of the spring 15 and the tapered surfaces 6a and 14a
, The optical disk 1 is in a state where play in the vertical and radial directions is restricted.

The outer case 3 is a rectangular box-shaped case for accommodating the disk case 2, and an entrance 16 is opened on one side of the peripheral surface. Similarly to the disk case 2, the outer case 3 is formed by joining plastically formed upper and lower cases 3a and 3b so as to cover each other.
The entrance 16 is covered with a lid 17 that can swing and open. The lid 17 is opened by loading the outer case 3 into the disk drive to open the entrance 16.

In order to prevent the disc case 2 loaded in the outer case 3 from being inadvertently pulled out, the two
A lock mechanism 4 is provided between the three. The lock mechanism 4 includes a lock claw 4a provided on the outer case 3 side,
And an engagement hole 4b provided on the side of the disk case 2.
When the outer case 3 is inserted and loaded into the disk drive, the lock claw 4a is unlocked against the spring by the release claw on the disk drive side to allow the disk case 2 to be removed.

When the disk cartridge is accidentally dropped from a high place, the optical disk 1
There is a possibility that the signal recording surface may abut against the inner wall of the disk case 2 by tilting or displacing in the radial direction against the pressing force of the disk case 2. In such a case, in order to prevent the signal recording surface of the disk main body 5 from being damaged, an optical disk is provided on one of the peripheral wall of the opening inside the case of the hub hole 14 and the lower surface of the optical disk 1 facing the peripheral wall of the opening. 1
The holding projection 20 for preventing the tilting of the ring is protruded annularly. In this embodiment, the holding projection 20 is formed integrally with the hub 6.

In FIG. 1, the hub 6 is made of a plastic molded product having an inverted truncated cone and a magnetic attraction plate 18 embedded and fixed to the lower end surface thereof, and a receiving seat 19 for the spring 15 on the upper surface.
Are recessed. The holding projection 20 is formed so as to protrude in a flange shape continuously from the outer peripheral upper edge of the hub 6, and the lower surface of the holding projection 20 contacts the opening peripheral wall of the hub hole 14 to secure the gap E. I have. That is, the holding projection 2
In a state where the lower surface of O is received and supported by the peripheral wall of the opening, the tapered surfaces 6a and 14a engaging with each other are opposed to each other with a minute gap therebetween. The hub 6 has a tapered surface 6a.
Occupies the entire hub peripheral surface below the protruding base end of the holding projection 20, whereas the tapered surface 1 of the hub hole 14
4a is formed only in the upper half of the hub hole 14, and the remaining lower half side hole 14b is formed as a circular hole that matches the lower end diameter of the tapered surface 14a. The lower end surface of the hub 6 is located slightly above the lower opening surface of the hole 14b.

In addition to the holding projection 20, a ring-shaped regulating projection 21 is provided on the peripheral wall of the opening inside the case of the hub hole 14. The inner peripheral surface of the regulating protrusion 21 is opposed to the outer peripheral surface of the holding protrusion 20 with a small gap therebetween, and regulates the optical disk 1 from moving in the radial direction beyond this gap. The upper end surface of the regulating protrusion 21 is opposed to the lower surface of the disk main body 5 via a minute gap. Note that the inner edge of the signal recording area of the disk main body 5 is located outside the diameter range of the outer peripheral surface of the regulating protrusion 21.

As described above, when the holding projection 20 received and supported by the peripheral wall of the opening of the hub hole 14 is provided on the lower surface of the optical disk 1, the optical disk 1 is subjected to a drop impact as shown in FIG. Hub hole 1 against 15 biasing force
4. When the user intends to lift and tilt from the
Of the optical disc 1 is received by the peripheral wall of the opening of the hub hole 14 and opposes the force of the optical disc 1 to tilt, so that even if the optical disc 1 can be slightly tilted, the optical disc 1 can immediately return to an appropriate standby posture. . At this time, since a return moment acts on the optical disc 1 with the radius value of the peripheral edge diameter of the holding protrusion 20 as a moment arm and the tension of the spring 15 as a restoring force, the optical disc 1 is returned only by the tension of the spring 15 alone. Optical disk 1 more reliably than
Can be restored.

When the optical disk 1 rises from the hub hole 14 and tilts, the hub 6 tends to move in the direction of the external force. However, even if the hub 6 is slightly displaced and moved, the peripheral surface thereof is received by the regulating protrusion 21, so that the optical disc 1
In the radial direction can be suppressed by the amount of radial gap between the two projections 20 and 21. Therefore, when the optical disc 1 is returned and tilted toward the hub hole 14 by the urging force of the spring 15, the hub 6 is smoothly returned and engaged with the hub hole 14.

When the disk cartridge is subjected to a drop impact, a part of the disk case 2, for example, the slide concave portion 11 may be bent and deformed, and its inner wall may come into contact with the optical disk 1 to damage the signal recording surface. is there. In order to prevent the signal recording surface from being damaged in such a case, an inclined wall 26 is formed on the inner surface of the disk case 2 facing the peripheral edge portion 25 of the disk body 5 as shown in FIG. Specifically, using a partition wall 27 provided inside the case along the periphery of the optical disc 1, an inclined wall 26 is integrally formed at an inner corner portion of the protruding base end. The optical disc 1 has room for displacement in the radial direction by the gap between the peripheral surface and the partition wall 27. Therefore, the width B in the radial direction of the inclined wall 26 is set to be at least twice as large as the allowance gap G. The degree of inclination of the inclined wall 26 is set based on the vertical gap between the disk main body 5 and the inner wall of the lower case 2b in the unused state. Specifically, when the optical disc 1 is positioned and held in the hub hole 14, the edge portion 25
Is set so as to be adjacent to the inclined wall 26 via a small margin. As a precaution, the inclined wall 26 can also be formed on the side of the upper case 2a.

When the disk case 2 is flexed and deformed, for example, by receiving a drop impact, the inclined wall 26 comes into contact with the edge portion 25 before the other case wall surface. Therefore, even if the slide recess 11 and the like are largely bent and deformed in a direction approaching the positioned and held disk body 5, the disk body 5 is accompanied by the case wall and slightly tilts while resisting the urging force of the spring 15. However, the signal recording surface does not come into contact with the case wall. When the external force is released and the case wall returns to the original state, the disk body 5 is pushed back to the original position by the spring 15. Since the edge portion 25 is outside the signal recording area, there is no problem even if the inclined wall 26 hits.

(Second Embodiment) FIG. 5 shows a second embodiment of the present invention. In this case, the holding projection 20 is provided as a ring-shaped projection on the peripheral wall of the opening inside the case of the hub hole 14. I have. At the center of the lower surface of the disk main body 5, a mounting seat 23 for the hub 6 is formed in a recess, and the inner bottom wall of the mounting seat 23 is received and held by the upper end surface of the holding projection 20. The diameter of the inner peripheral surface of the mounting seat 23 is set slightly larger than the diameter of the outer peripheral surface of the holding projection 20.
By receiving at 0, it is possible to prevent the optical disc 1 from shifting significantly in the radial direction. As can be understood from this, the mounting seat 23 also serves as a regulating recess 24 that regulates the radial movement of the optical disc 1. The tapered surface 14 a on the hub hole 14 side extends to the upper end of the holding projection 20. Since the other configuration is the same as that of the first embodiment, the same reference numerals are given to the same members, and the description is omitted. The restriction recess 24 can be formed in a ring groove shape outward from the joint surface of the hub 6 to the disk body 5.

In the first and second embodiments, the regulating projection 21 and the regulating recess 24 can be omitted when the gap E is sufficiently large. The holding projection 20 can be formed integrally with the disk body 5. In the second embodiment, the regulating protrusion 21 can be formed integrally with the disk main body 5 after the regulating recess 24 is omitted. The present invention can be applied to a disk cartridge in which the outer case 3 is omitted. The holding projection 20 and the regulating projection 21 are each formed in a series of ring shapes,
It can be formed in an intermittent ring shape.

[0033]

According to the present invention, the holding projection 20 is provided on one of the inner wall of the opening of the hub hole 14 and the lower surface of the disk 1 facing the inner wall, so that the disk 1 can be moved by the drop impact. 14, the holding projection 20 or the holding projection 20 applies the force in the tilting direction.
The disc 1 can be received on the wall opposite to it, so that the disc 1 can be prevented from further tilting. Therefore, even if the disc cartridge receives a strong force due to careless handling or rough handling, etc. It is possible to reliably prevent the disk 1 from tilting and its signal recording surface from coming into contact with the disk case 2 and being damaged. Thereby, the reliability of the disk cartridge can be improved, and a disk cartridge suitable for an optical disk having a particularly high signal recording density can be obtained.

[Brief description of the drawings]

FIG. 1 is a sectional view taken along line AA in FIG.

FIG. 2 is an internal plan view of the disk cartridge.

FIG. 3 is a cross-sectional view showing a tilted state of the disk.

FIG. 4 is a sectional view of a main part of the disk cartridge.

FIG. 5 is a sectional view showing another embodiment of the holding projection.

[Explanation of symbols]

 Reference Signs List 1 disk (optical disk) 2 disk case 5 disk body 6 hub 6a tapered surface 14 hub hole 14a tapered surface 20 holding projection 21 regulating projection

Claims (7)

[Claims] 1. A disk 1 having a hub 6 on a lower surface of a disk main body 5 for reading and writing a signal, and a disk case 2 for accommodating the disk 1 in a rotatable state. The hub 6 is pressed down and urged by a spring 15 disposed between the hub 6 and the disk case 2, and is received and held by a hub hole 14 provided in the disk case 2. Ball-shaped tapered surface 6a
A disk cartridge that is engaged and held via the first hole 14a and positioned and held in a state where the signal recording surface of the disk body 5 faces the inner wall of the disk case 2 via the gap E; A holding projection 20 is provided on one of the inner peripheral wall of the opening and the lower surface of the disk 1 facing the opening peripheral wall so as to protrude in a ring shape in contact with the opposite wall to prevent the disk 1 from tilting. Disc cartridge. 2. A holding projection 20 is provided on the periphery of the hub 6.
2. The disc cartridge according to claim 1, wherein the disc cartridge is formed integrally with the disc cartridge. 3. A regulating projection 21 which receives the peripheral surface of the holding projection 20 and regulates the radial movement of the disk 1 on the peripheral wall of the opening inside the case of the hub hole 14. Disk cartridge. 4. The disk cartridge according to claim 1, wherein the holding projections 20 are annularly projecting from the peripheral wall of the opening inside the hub hole 14. 5. A restricting recess 24 for restricting radial movement of the disk 1 is provided on the lower surface of the disk main body 5 surrounding the hub 6 so as to abut against the peripheral surface of the holding projection 20. Disk cartridge. 6. The signal recording surface of the disk body 5 is scratched on the inner surface of the disk case 2 facing the peripheral edge portion 25 of the disk body 5 by contacting the edge portion 25 prior to the other case wall surface. 6. The disc cartridge according to claim 1, wherein an inclined wall 26 for preventing sticking is formed. 7. The radial width B of the inclined wall 26 is equal to the radial clearance G between the disk 1 and the disk case 2.
7. The disk cartridge according to claim 6, wherein the value is set to twice or more of the following.