JPH01128284A - Recording medium cassette - Google Patents

Abstract

PURPOSE:To prevent the occurrence of large load fluctuation in a driving system by giving a protrusion provided on a part of the inner surface of a cassette case with facing nearly the center part of a rotary driving body or a recording medium. CONSTITUTION:The protrusion 7 is integrally generated on a position which is almost coincident with the rotational axis of the magnetic disk 3 in the inner surface of an upper case 1. The protrusion 7 is integrally generated by a mold processing at the time of shaping the upper case 1. The protrusion 7 is provided on the center position of a center hub. When the cassette case, especially the upper case 1 is deformed and the center part is recessed with such constitution, the protrusion 7 is abutted on the center and the other parts are not brought into contact with a drive pin 6. Since the protrusion 7 is abutted on the center of a center hub 4, namely, the rotary center position of the magnetic disk 3, large load fluctuation does not occur in the driving system connected to a spindle axis 5 even if the protrusion is brought into contact with the center hub.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a recording medium cassette, and particularly to a recording medium cassette that stores a disc-shaped recording medium therein.

[Prior Art] Conventionally, optical disks, magnetic disks, records with physical grooves, and the like have been known as devices using disc-shaped recording media. In recent years, optical discs,
Magnetic disks are widely used for digital recording of sounds, images, characters, numbers, etc.

Particularly, for optical disks and magnetic disks, a configuration is known in which a disk serving as a recording medium is stored in a cassette and the entire cassette is loaded into a device. FIGS. 5 and 6 show the structure of a conventional recording medium cassette that accommodates a 3.5-inch magnetic disk.

In FIG. 5, reference numeral 1.2 denotes an upper case and a lower case of a cassette made of plastic or the like, in which the magnetic disk 3 is rotatably housed.

A center hub 4 is attached to the center of the flexible magnetic disk 3, and is rotated via the center hub 4 by a spindle 5 of a magnetic disk device inserted into the cassette through the opening 2a of the lower case 2. . The center hub 4 and the spindle 5 are coupled by a drive pin 6 eccentrically provided on the upper surface of the spindle 5.

[Problem to be solved by the invention] In the case of Fig. 5, the upper case 1 and the lower case 2 are fixed, and b
Since the n-air disk 3, center hub 4, and spindle 5 are rotationally driven, it is desirable that the rotating parts do not come into contact with the inside of the cassette case. Therefore, in the structure shown in FIG. 5, in the normal driving state, the magnetic disk 3 is rotated in a position where it slightly rises above the lower case 2, and the upper surfaces of the drive pins 6 and center hub 4 are connected to the upper case 2.
There are four circular parts 1 on the inner surface of the upper case 1 to prevent contact with the
A is provided.

Furthermore, as shown in FIG. 6, a structure has also been proposed in which the shaft 5a of the spindle 5 is extended and brought into contact with the upper case 1 to rotationally drive the magnetic disk. With the structure shown in FIG. 6, the center of rotation of the spindle shaft 5a contacts the upper case 1, and the drive bin 6 is prevented from contacting the upper case 1.

However, in the conventional structure shown in Figs. 5 and 6, if the cassette case made of plastic or the like is distorted, the eccentric drive pin 6 hits the inner surface of the upper case, causing a load on the disk drive motor. This may cause fluctuations in the disk rotation speed, making it impossible to perform normal recording and playback, or the sliding between the drive bin 6 and the cassette case may generate shavings, causing foreign matter inside the cassette case and damaging the magnetic disk. There was some danger.

The above problems are not limited to magnetic disk cassettes, but also apply to cassette cases that house recording medium disks of other types.

[Means for Solving the Problems] In order to solve the above problems, the present invention includes a cassette case and a rotational drive member housed inside the cassette case and inserted into the inside from a predetermined opening of one cassette case. The present invention employs a configuration including a disc-shaped recording medium that is rotationally driven by a cassette case, and a protrusion provided on a part of the inner surface of the cassette case facing the rotational drive unit side or substantially the center of the recording medium.

[Function] According to the above configuration, even if the cassette case is deformed, the protrusion provided on a part of the inner surface of the cassette case contacts the center of the rotating part, and the rotating part is prevented from contacting the cassette case. Prevented.

[Example] Hereinafter, the present invention will be described in detail based on the example shown in the drawings.

FIG. 1 shows the structure of a magnetic disk cassette as an embodiment of a recording medium cassette employing the present invention. In the following embodiments, the same reference numerals are given to the same or corresponding members as in the above-mentioned conventional example, and detailed explanation thereof will be omitted.

In the structure shown in FIG. 1, the magnetic disk 3 on the inner surface of the upper case 1
A protrusion 7 is integrally formed at a position substantially coinciding with the rotation axis. The protrusion 7 is integrally formed by molding or the like when the upper case 1 is molded. As shown in FIG. 2, the protrusion 7 is provided at the center of the center hub 4. As shown in FIG.

According to this structure, when the cassette case, especially the upper case 1, is deformed and its central portion is depressed as shown in FIG. 3, the protrusion 7 comes into contact with the center of the center hub 4 and the other parts There is no contact with the drive pin 5. Protrusion 7
Since it is in contact with the center of the center hub 4, that is, the center of rotation of the magnetic disk 3, even if it comes into contact with the center hub, there will be no large load fluctuation on the drive system connected to the spindle shaft 5. This does not significantly affect the disk rotation speed. Furthermore, since the drive pin 6 is prevented from coming into contact with the inner surface of the upper case 1, the magnetic disk 3 is prevented from being damaged by shavings or the like from the upper case 1. Furthermore, the protrusion 7 can be easily formed by molding, etc., and there is no need to process the spindle shaft which requires precision as in the conventional example shown in FIG.

FIG. 4 shows a modification of the above embodiment.

In the structure shown in FIG. 4, instead of the protrusion 7, a sphere 8 made of plastic, metal, etc. is rotatably attached.

According to such a structure, even if the cassette case is deformed, the sphere 8 comes into contact with the center hub 4, and as described above, the drive pin and other rotating parts are prevented from coming into contact with the inside of the cassette case. In this case, since the sphere 8 is rotatably attached to the upper case 1, the increase in load on the rotational drive system can be made smaller than in the previous embodiment.

The above example illustrates the structure of a magnetic disk cassette that stores a flexible magnetic disk, but the same structure can also be applied to a cassette case that stores a recording medium disk using other recording/playback methods or a recording medium disk that has some degree of rigidity. can do.

[Effects of the Invention] As is clear from the above description, according to the present invention, rotation is performed by a cassette case and a rotary drive member housed inside the cassette case and inserted into the inside from a predetermined opening of the cassette case. Since the configuration includes a disk-shaped recording medium to be driven and a protrusion provided on a part of the inner surface of the cassette case facing the rotational drive member or substantially the center of the recording medium, the cassette case Even if the cassette is deformed, the protrusion provided on the inner surface of the cassette case contacts the approximate center of the rotating part, preventing other parts from contacting the inner surface of the cassette case, thereby increasing the load on the recording medium drive system. This has the excellent effect of suppressing fluctuations in the rotational speed of the recording medium, suppressing the generation of shavings on the cassette case, and preventing damage to the recording medium.

[Brief explanation of the drawing]

Fig. 1 is a sectional view showing the structure of a magnetic disk cassette employing the present invention, Fig. 2 is an explanatory diagram of the structure shown in Fig. 1 seen from above, and Fig. 3 is the effect of the protrusion provided on the upper case. FIG. 4 is a cross-sectional view showing different embodiments of the magnetic disk cassette of the present invention, and FIGS. 5 and 6 are cross-sectional views showing different conventional structures. 1... Upper case 2... Lower case 3... Magnetic disk 4... Center hub 5... Spindle 6... Drive bin 7... Protrusion
8... Sphere NI+/

Claims (1)

[Claims] a cassette case, a disc-shaped recording medium housed inside the cassette case and rotationally driven by a rotational drive member inserted into the cassette case from a predetermined opening; A recording medium cassette characterized by having a protrusion provided on a part of the inner surface of the cassette case substantially facing the center part.