JPH0538433Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a center core of a disk-shaped recording medium, and particularly relates to a center core of a disk-shaped recording medium, and in particular, to a center core of a disk-shaped recording medium, and in particular to a center core of a disk-shaped recording medium, and in particular to a center core of a disk-shaped recording medium, and in particular to a center core of a disk-shaped recording medium. The present invention relates to a center core of a disk-shaped recording medium on which information is reproduced.

[Conventional technology]

Recently, imaging devices such as solid-state image sensors and image pickup tubes,
In combination with a recording device that uses a magnetic disk, which is inexpensive and has a relatively large storage capacity, as a recording medium, the subject is still photographed purely electronically and recorded on a rotating magnetic disk, and the images are played back using a separate television system or An electronic still camera system that uses a printer or the like has been developed and is attracting attention.

The magnetic disks used in such systems are used in the form of magnetic recording cartridges. A magnetic recording cartridge rotatably stores a magnetic disk for magnetically recording still image information, etc.
This magnetic recording cartridge is used by being attached to a magnetic recording device built into an electronic camera or a reproducing device that may be integrated with or separate from the magnetic recording device. When installing a magnetic recording cartridge into a magnetic recording device or reproducing device in an electronic camera, connect the center hole provided in the center core of the magnetic disk in the magnetic recording cartridge directly to the rotational drive shaft of the magnetic recording or reproducing device. Mounting the magnetic recording cartridge is troublesome and inconvenient, and there is a possibility that the magnetic recording cartridge cannot be correctly mounted on the magnetic recording or reproducing apparatus.

In order to eliminate such troubles, two types of magnetic recording cartridge attachment/detachment devices have been proposed in the past. It is composed of an upper lid and a bucket that is integrally formed with the upper lid or is pivotally supported on the main body or the upper lid, and the magnetic recording cartridge in the bucket is inserted into the bucket and then closed. A magnetic disk can be attached to the rotational drive shaft of the main body of the device. Further, the second magnetic recording cartridge attachment/detachment device includes:
When the recording cartridge is inserted halfway into the slot-like opening, the recording cartridge can be automatically pulled into the apparatus and the magnetic disk of the recording cartridge can be chucked. Both of these two types of attachment/detachment devices have a center core pushing mechanism which will be described later. Further, a center core is provided at the center of the magnetic disk, and the rotation drive shaft is fitted into the center hole of the center core to rotate the magnetic disk within the magnetic recording cartridge.

By the way, the center core of the magnetic disk must be accurately attached to the rotational drive shaft. If this attachment is insufficient, the magnetic disk may cause eccentric rotation or uneven rotation, making it difficult for the magnetic head to accurately record signals on the magnetic disk. Not only is there a risk that the data will not be played back, but there is also a risk that it will have an adverse effect on the magnetic disk, magnetic head, etc. For this reason, the center core of conventional magnetic disks has a tapered surface for positioning and a resin elastic piece formed in the center hole into which the drive shaft is inserted, and the center core is pressed against the drive shaft with a predetermined pressing force. Then, the drive shaft is positioned on the tapered surface by the biasing force of the elastic piece, and the center core is accurately mounted on the drive shaft.

However, the resin elastic piece has low durability and heat resistance and may be plastically deformed, causing misalignment of the magnetic disk and eccentric rotation of the magnetic disk. In order to solve this problem,
Japanese Patent No. 138063 proposes a center core that uses a metal leaf spring instead of a resin elastic piece. This metal plate spring supports both ends of the metal plate spring in the center hole of the center core into which the rotation drive shaft of the magnetic recording/reproducing device is inserted, and the rotation drive shaft inserted into the center hole is inserted into the center core. It is characterized in that it is pressed against a tapered surface formed on the opposing surface of.

[Problem that the invention attempts to solve]

However, in order to obtain the elastic force of a conventional metal leaf spring, the distance between the tapered surface and the leaf spring is made smaller than the diameter of the drive shaft, making chucking difficult. For this reason, a center core pushing mechanism was required. Further, since the flat surface of the leaf spring comes into contact with the rotary drive shaft, a relatively large frictional force (ie, insertion resistance) is generated between the rotary drive shaft and the leaf spring when the magnetic recording cartridge is installed in the reproducing apparatus. Therefore, in order to reliably chuck the center core into the reproducing apparatus, the center core pushing mechanism of the reproducing apparatus requires a relatively large center core pushing force, which has the disadvantage of increasing costs.

Further, since a large load is applied to the spindle motor via the center core, there is a drawback that the bearing of the spindle motor is easily damaged.

Furthermore, there is a proportional relationship between the insertion resistance of the leaf spring and the chucking force, and in order to reduce the insertion resistance, it is necessary to reduce the chucking force below a limit value. As a result, there was a drawback that the center core could not be accurately positioned against the attraction force of the chucking magnet of the regenerator.

The present invention was developed in view of the above circumstances, and reduces costs by reducing the center core pushing force of the center core pushing mechanism of the playback device without reducing the chucking spring force, or by eliminating the need for the center core pushing mechanism. It is an object of the present invention to provide a center core of a disk-shaped recording medium.

[Means for solving problems]

In order to achieve the above object, the present invention has a center hole that is formed at the center of a magnetic disk and can be inserted into the rotation drive shaft of a magnetic recording/reproducing device, and the disk is attached to the rotation drive shaft through this center hole. In the center core of a disk-shaped recording medium, a contact member that contacts the rotational drive shaft is provided in the center hole, and the contact member is rotatably supported with elasticity in the direction of the rotational drive shaft. It is characterized by

[Effect]

According to the present invention, since the contact member that holds the rotary drive shaft in the chucking state is rotatably supported, the insertion resistance of the rotary drive shaft can be reduced without reducing the chucking spring force.

〔Example〕

Preferred embodiments of the center core of the disk state recording medium according to the present invention will be described in detail below with reference to the accompanying drawings.

FIG. 4 is a plan view of the magnetic recording cartridge in which the magnetic recording cartridge is stored, and FIG. 5 is a sectional view taken along the line A--A in FIG. 4. As shown in FIG. 4, the hard case of the magnetic recording cartridge 10 has a substantially rectangular shape, and a magnetic disk 12 on which still image information and the like are recorded is rotatably housed inside the hard case. A center core 14 as a reinforcing member is provided at the center of the magnetic disk 12, and the center core 14 is exposed to the outside through a circular opening 16 of the magnetic recording cartridge 10. The magnetic recording cartridge 10 has a window 18 in which a magnetic head (described later) is located, and this magnetic head window 18 is opened and closed by a slideable shutter 20. That is, before the magnetic recording cartridge 10 is inserted into a bucket, which will be described later, the shutter 20 closes the window 18 and closes the magnetic disk 1.
When the shutter 20 is inserted into the bucket, the shutter 20 moves downward in FIG. .

Further, as shown in FIG. 5, by using a metal core plate 30 as a part of the center core 14 and disposing a magnet 22B on the receiving surface 22A of the rotating shaft 22, the rotating shaft 22 can be attached to the center hole 15. It can be inserted reliably.

As shown in FIGS. 1A and 1B, the core plate 30 is formed into a disk shape, and a core block 32 made of resin is fixed to the center thereof. Tapered surfaces 15B, 15B are formed on the inner circumferential surface 15A of the center hole 15 of the core block 32, and the inclined surface of the rotary drive shaft 22 abuts on these tapered surfaces. Further, a slit 38 is formed in the core block 32, and protrusions 38A, 38A are formed at both ends of the slit 38.

The leaf spring 34 has both ends disposed within the slits 38 and can bend with the projections 38A, 38A as fulcrums.
The core block 32 has a slit 38 and an inner peripheral surface 15A.
The long hole 40 is formed to open to the
As shown in FIG. 1C, the wall surface of the plate spring 34 is tapered to make the opening width of the long hole 40 on the plate spring 34 side
The diameter of the metal ball 35 is larger than that of the long hole 4 on the opposite side.
The opening width of the contact member 30 is made smaller than the diameter of the metal ball 35.
5 is pressed against a leaf spring 34 and supported rotatably within a long hole 40.

The operation of the center core of the disk-shaped recording medium according to the present invention constructed as described above will be explained.

First, when the magnetic recording cartridge is stored in the playback device and the rotary drive shaft 22 is inserted into the central hole 15, the rotary drive shaft 22 comes into contact with the metal ball 35 and the plate spring is released, as shown in FIG. 1B. 34 is received via the metal ball 35. metal ball is
Since the rotary drive shaft 22 rotates as it is inserted, the insertion resistance of the rotary drive shaft 22 is reduced. At this time, the rotary drive shaft 22 is accurately chucked because it receives the biasing force of the leaf spring having chucking spring force.

Although metal balls were used in the embodiment, the ball is not limited to this, and as shown in FIG. 2, a cylindrical roller 41 with tapered ends may be used.

Further, although the leaf spring and the metal ball were used in the above embodiment, the present invention is not limited to this, and as shown in FIGS. 3A and 3B, a pin-shaped chucking spring 42 may be rotatably supported on the core block 32. good. In this case, since the number of parts is reduced compared to the above embodiment, it is possible to reduce costs.

[Effect of idea]

As explained above, according to the center core of the disk-shaped recording medium according to the present invention, it is possible to reduce the insertion resistance of the rotational drive shaft without reducing the chucking spring force, so that it is possible to reliably use the magnetic recording/reproducing device. In addition, the center core pushing force of the center core pushing mechanism of this playback device can be reduced, or the center core pushing mechanism can be made unnecessary. Therefore, it is possible to reduce the cost of the center core pushing mechanism, and to eliminate disadvantages such as damage to the spindle motor bearing when the center core pushing force is large.

[Brief explanation of the drawing]

1A is a plan view of the magnetic recording cartridge according to the present invention, FIG. 1B is a sectional view taken along line AA in FIG. 1, FIG. 1C is a detailed view of B in FIG. FIG. 3A is a plan view showing another embodiment of the magnetic recording cartridge according to the present invention;
3B is a cross-sectional view taken along the line C-C in FIG. 3A, FIG. 4 is a plan view of a magnetic recording cartridge in which the magnetic recording cartridge according to the present invention is housed, and FIG. 5 is taken along the line A-A in FIG. 4. FIG. 10... Magnetic recording cartridge, 12... Magnetic disk, 14... Center core, 15... Center hole, 15A... Inner peripheral surface, 15B... Tapered surface, 2
2... Rotation drive shaft, 34... Leaf spring, 35... Metal ball, 40... Roller, 42... Chatting spring.

Claims (1)

[Claims for Utility Model Registration] A disc-shaped recording medium has a center hole formed at the center thereof and can be inserted into a rotational drive shaft of a recording/reproducing device,
In the center core of the disk-shaped recording medium that is attached to the rotation drive shaft through the center hole, a contact member that contacts the rotation drive shaft is provided in the center hole, and the contact member is rotatably attached to the rotation drive shaft. A center core of a disk-shaped recording medium characterized by being elastically supported in the direction of.