JPH08255453A - Magnetic disk cartridge - Google Patents

Abstract

PURPOSE: To improve the dimensional accuracy of a cassette shell, and to impart an auto-loading function in a magnetic disk cartridge. CONSTITUTION: A pair of at least guide grooves 10, 10 extended along the direction of the insertion of a magnetic disk cartridge 1 to a magnetic-disk cartridge driving device are made on the external surface of a cassette shell 3 at approximately symmetric places. Tooth-shaped sections 10a being engaged with a driving gear section for an auto-loading fitted on the magnetic-disk cartridge driving device side and enabling automatic-mounting and dismounting of the magnetic disk cartridge 1 to the magnetic-disk cartridge driving device are formed to the bases of the guide grooves 10, 10.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic disk cartridge, and more particularly to an improvement of a cassette shell of a magnetic disk cartridge having a cassette shell rotatably containing a magnetic disk.

[0002]

2. Description of the Related Art In a magnetic disk cartridge, a magnetic disk for magnetically recording an analog or digital signal is freely rotatable in a thin cassette shell composed of a pair of plastic cassette shell halves which are joined and fixed to each other. The cassette shell, which is built in, has a substantially square upper surface slightly larger than the magnetic disk, a bottom surface having an opening for exposing the center core supporting the center of the magnetic disk, and extends between the upper surface and the peripheral edge of the bottom surface. It is formed in a flat prismatic shape (substantially square shape) consisting of narrow side surfaces. The magnetic disk cartridge is provided with a magnetic head insertion slot into / from which magnetic heads for magnetic recording / reproduction come in and out on both sides of the magnetic disk from the outside or come close to each other. An open / close shutter is provided to prevent dust and the like from entering at the time.

A liner made of non-woven fabric is attached to the inner surface of the cassette shell facing the magnetic disk so that the surface of the magnetic disk is not damaged when the magnetic disk rotates. It is designed to wipe off dust and the like adhering to.

[0004]

In recent years, 50 of magnetic disk cartridges (3.5-inch floppy disks), which have been widely used in the past, have been introduced by a new high-density recording system.
Magnetic disk cartridges with double the recording capacity have been developed. In such a magnetic disk cartridge, in order to increase the recording density and the transfer rate, the disk of the magnetic disk is rotated at a much higher speed than the conventional one, and at the time of recording / reproducing a signal, it is extremely higher than the magnetic head. Positional accuracy is required. Further, in order to further increase the effective recording capacity, a so-called auto-loading function has been strongly demanded, in which a plurality of large-capacity magnetic disk cartridges can be automatically exchanged without human labor.

Further, in such a magnetic disk cartridge, a magnetic head insertion opening having a size capable of being exposed to both sides of the magnetic disk is provided on one side surface of the cassette shell, and the magnetic head for recording and reproducing is described above. It is configured to be inserted from the magnetic head insertion port and to be recorded and reproduced in the vicinity of a magnetic disk rotating at high speed. Therefore, the cassette shell needs to have a predetermined thickness into which the magnetic head can be inserted.

On the other hand, since the magnetic disk that rotates at a high speed inside the cassette shell is made of a flexible material, it is necessary to suppress fluttering at the time of rotation. Dimensions (generally the thickness of the magnetic disk and liner plus some clearance) are required. In order to realize this dimension with high precision, the cassette shell needs to have sufficient rigidity, and for that purpose, the cassette shell needs to have sufficient thickness.

For the above reasons, it is necessary to increase the thickness of the cassette shell, for example, twice or more as compared with the thickness (about 3 mm) of the cassette shell of the conventional 3.5 inch floppy disk. Yes, according to this,
The plate thickness of the pair of cassette shell halves themselves, which are joined and fixed to each other to form the cassette shell, is also considerably large.

However, the cassette shell having such a thick structure is heavy in weight and requires a large amount of material and a long molding time in manufacturing, which not only causes an increase in cost, but also "Sink" on the thick part
A problem that cannot be overlooked is the adverse effect on quality, which is caused by deformation called "," which deteriorates dimensional accuracy and appearance.

A first object of the present invention is to provide a magnetic disk cartridge with an auto-loading function for a magnetic disk cartridge driving device.

A second object of the present invention is, in addition to the first object, to reduce the weight of the cassette shell and improve the productivity and quality of the magnetic disk cartridge as described above.

[0011]

In the magnetic disk cartridge according to the present invention, at least a pair of guide grooves extending along the insertion direction of the magnetic disk cartridge into the magnetic disk cartridge drive device are provided on the outer surface of the cassette shell at substantially symmetrical positions. It is characterized in that it is provided in.

Further, in the magnetic disk cartridge according to the present invention, an automatic loading drive gear portion provided on the magnetic disk cartridge driving device side is engaged with the bottom surface of the guide groove to automatically drive the magnetic disk cartridge to the driving device. An automatic loading function can be imparted by providing a tooth-shaped portion that allows the mechanical attachment / detachment along the guide groove.

When the tooth portion is provided on the bottom surface of the guide groove, one end of the guide groove is opened only on the side surface of the cassette shell where the magnetic head insertion opening is provided.
The other end of the guide groove is preferably closed.

It is preferable that the guide groove has a substantially trapezoidal shape in which a cross section taken along a plane orthogonal to its extension direction opens outward.

[0015]

In the magnetic disk cartridge according to the present invention, the guide groove is provided with a tooth-shaped portion which meshes with the drive gear portion for auto-loading provided on the magnetic disk cartridge driving device side. It is possible to add an auto loading function to the cartridge.

Then, one end of the guide groove is opened only on the side surface of the cassette shell where the magnetic head insertion opening is provided, and the other end of the guide groove is closed.
Only the magnetic disk cartridge can be loaded with the magnetic head insertion port facing the magnetic disk cartridge drive unit, and the opposite direction cannot be loaded. Can be prevented.

Further, since at least a pair of guide grooves are provided on the outer surface of the cassette shell, that portion is thinned, so that the weight of the cassette shell is reduced and the productivity is improved by shortening the molding time. In addition, it is possible to improve dimensional accuracy and appearance quality inside the cassette shell.

The guide groove has a substantially trapezoidal shape in which the cross-section taken along a plane orthogonal to the extension direction thereof is opened outward, so that the resin flow at the time of molding the cassette shell half is improved. You can

[0019]

Embodiments of the magnetic disk cartridge according to the present invention will be described below with reference to the accompanying drawings.

1 and 2 show an embodiment of a magnetic disk cartridge according to the present invention. FIG. 1 is a perspective view,
FIG. 2 is a sectional view taken along the line II-II in FIG.

The magnetic disk cartridge 1 comprises a cassette shell 3 which rotatably houses a magnetic disk 2 therein. The cassette shell 3 is formed by plastic molding and is a pair of upper and lower cassette shell halves. It is composed of four and five. On one side of the cassette shell 3, a magnetic recording / reproducing head is attached to the magnetic disk 2.
Magnetic head insertion port 3 for approaching both sides of the
a is provided, and the magnetic head insertion port 3a is provided here.
A shutter member 6 having a U-shaped cross section for opening and closing is attached slidably in a manner biased toward a closed position by a spring (not shown). Note that FIG. 1 shows a state (closed position) in which the magnetic head insertion opening 3a is closed by the shutter member 6.

In one of the cassette shell halves 4 located on the lower side in the figure, a circular opening 4a exposing a center core 7 for fixing and supporting the central portion of the magnetic disk 2 is exposed.
The doughnut-shaped liner 8 made of a nonwoven fabric having a circular hole 8a having a diameter slightly larger than that of the circular opening 4a is attached to the inner surface 4b of the cassette shell half 4 by ultrasonic welding or the like. There is. Further, on the inner surface of the other cassette shell half 5 located on the upper side in the figure, a donut-shaped liner 9 made of a non-woven fabric having a circular hole 9a for avoiding interference with the flange portion 7a of the center core 7 is provided. It is attached in the same manner as in No. 8.

In the figure, the central portion of the upper surface of the cassette shell half 5 located on the upper side is a label sticking area 5a, and a drive unit (not shown) of the magnetic disk cartridge 1 is provided on both sides of the label sticking area 5a. The guide grooves 10, 10 extending along the inserting direction of the magnetic disk cartridge 1 with respect to
Thin portions 5b, 5b are formed at the bottoms of the guide grooves 10, 10.

Although one end of each of the guide grooves 10 and 10 is open on the side surface 5c of the cassette shell half 5 where the magnetic head insertion opening 3a is provided, on both sides of the sliding area of the shutter member 6. , The other ends of the guide grooves 10, 10 terminate on the upper surface of the cassette shell half 5,
There is no opening on the side surface 5d of the cassette shell half 5 opposite to the magnetic head insertion opening 3a side.

As shown in FIG. 2, the guide grooves 10 and 10 have a substantially trapezoidal shape in which a cross section along a plane orthogonal to the extending direction thereof is open outward, whereby a cassette is formed. The flow of the resin at the time of molding the shell half 5 is made good, the molding strain is alleviated, the releasability from the molding die is improved, the strain applied to the cassette shell half is reduced, and the accuracy is improved.

On the bottom surface of the guide groove 10, 10, a tooth-shaped portion 10 for engaging the magnetic disk cartridge 1 with a driving gear portion for automatic loading provided on the driving device side.
a is provided along each of the guide grooves 10 and 10 to enable automatic attachment / detachment of the magnetic disk cartridge 1 to / from the drive device.

In the construction of the embodiment of the magnetic disk cartridge according to the present invention, the guide grooves 10, 10 are provided.
A toothed portion 1 that meshes with a drive gear portion for auto loading provided on the magnetic disk cartridge drive device side.
By providing 0a, in addition to providing the magnetic disk cartridge with the auto-loading function, it is possible to obtain the effect of improving the dimensional accuracy by thinning the cassette shell 3.

Then, one end of the guide grooves 10 and 10 is opened only on the side surface 5c of the cassette shell half 5 where the magnetic head insertion opening 3 is provided, and the other ends of the guide grooves 10 and 10 are closed so that the magnetic field is reduced. It is possible to only load the magnetic disk cartridge 1 with the head insertion opening 3a facing the magnetic disk cartridge drive device, and to prevent the magnetic disk cartridge 1 from being loaded in the opposite direction, thereby preventing an erroneous insertion operation.

The guide grooves 10 and 10 may be provided not on the cassette shell half 5 side but on the lower cassette shell half 4 side, or may be provided on both the cassette shell halves 4 and 5.

[Brief description of drawings]

FIG. 1 is a perspective view of a magnetic disk cartridge according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along line II-II in FIG.

[Explanation of symbols]

 1 magnetic disk cartridge 2 magnetic disk 3 cassette shell 3a cassette shell magnetic head insertion opening 4, 5 cassette shell half 4a opening for exposing the center core 5a cassette shell half label attachment area 5b cassette shell half thin portion 5c cassette shell half Side surface 6 Shutter member 7 Center core 8,9 Liner 10 Guide groove 10a Toothed portion 10a of guide groove

Claims (4)

[Claims] 1. A cassette shell composed of a pair of cassette shell halves that are rotatably housed in a magnetic disk and are coupled to each other, and a magnetic head insertion opening opened and closed by a shutter member is provided on one side surface of the cassette shell. A magnetic disk cartridge, wherein one cassette shell half is provided with an opening for exposing a center core for fixing and supporting the center of the magnetic disk, wherein the cassette shell has an outer surface with respect to a magnetic disk cartridge driving device. A magnetic disk cartridge, wherein at least a pair of guide grooves extending along the inserting direction of the magnetic disk cartridge are provided at substantially symmetrical positions. 2. A tooth that meshes with a drive gear portion for auto-loading provided on the magnetic disk cartridge drive device side on the bottom surface of the guide groove to enable automatic attachment / detachment of the magnetic disk cartridge to / from the drive device. 2. The magnetic disk cartridge according to claim 1, wherein a groove is provided along the guide groove. 3. The one end of the guide groove is opened on the side surface of the cassette shell on which the magnetic head insertion opening is provided, and the other end of the guide groove is closed. The magnetic disk cartridge described. 4. The guide groove according to claim 1, wherein the guide groove has a substantially trapezoidal shape in which a cross section taken along a plane orthogonal to the extension direction thereof opens outward. Magnetic disk cartridge.