JPS5812176A - Floppy disk cassette - Google Patents

Abstract

PURPOSE:To ensure the use of both surfaces of a floppy disk for a magnetic recorder/reproducer for the single side use, by providing an opening part for detection of the index hole at a part of a cassette and securing the use of the cassette although it is turned over. CONSTITUTION:An opening part 3 for detection of the index hole is provided at a part of a cassette 1 storing a floppy disk 2, and as a result the cassette 1 can be used although it is turned over. For instance, the opening part 3 is set at a position as shown in the diagram. Then the index holes 4a and 4b are set with a shift of phase secured to the turning direction of a floppy disk 2. Then a detecting means like a light emitting element, a photodetecting element, etc. is provided to detect the holes 4a and 4b. When the surface A is used, the detecting signal produced through the hole 4a is delivered first as shown by A in the diagram. The producing sequence of the signal is reversed in the case of the use of the surface B. MAking use of this fact, the discrimination is performed between the surface and back sides of the disk 2.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a floppy disk cassette, and more particularly to a floppy disk cassette in which both sides of the floppy disk can be used by flipping the floppy disk cassette over.

A floppy disk is a magnetic recording medium in the form of a disk, and is quite flexible, so it is housed in a cassette made of cardboard, synthetic resin, or the like. There are two types of floppy disks: one for single-sided disks and one for double-sided disks. Single-sided disks are for one side only, and index holes are provided at asymmetric positions on the front and back sides. Also, for double-sided disks, the magnetic recording/reproducing device side (Nifloppy disk) has a double-sided magnetic head structure, and the index hole is also in an asymmetrical position, just like for single-sided disks, making it impossible to use them upside down. It is.

In the case of a double-sided floppy disk, it is possible to use it by creating another opening on the cassette side opposite each index hole and turning it over, but the magnetic recording/reproducing device cannot distinguish between the front and the back. In addition, there were two openings for detecting the index hole.If the front and back sides were to be discriminated, a signal had to be generated by other means.

FIG. 1 shows a conventional example of such a structure.

That is, the floppy disk cassette, which is indicated by the reference numeral 1 in Figure 1, has upper and lower covers, -
Stack 1a and lb and insert floppy disk 2 between them.
Adopts a structure that maintains the Upper and lower covers 1a, l
An opening 1c into which a drive device for clamping and rotating the floppy disk 2 is fitted is formed in the center of b, and a rectangular opening 1d into which a magnetic head is inserted and scanned is formed. There is. Further, index openings 3a and 3b are formed on both sides of the opening 1C.
Using these openings, the index hole 4 formed on the floppy disk side is detected. With this structure, when the A side is used, the index hole is detected by the light emitting element 6 and the light receiving element 7 arranged above and below it through the opening 3a, and when the B side is used upside down, the index hole is detected by the opening 3b. are using. Reference numeral 5 indicates a display label.

If such a structure is adopted, both sides of the floppy disk can be used as described above, but C2, which discriminates between the front and the back, needs to generate a discrimination signal by other means, making the device complicated and expensive. It becomes a thing.

The present invention has been made in order to eliminate the above-mentioned drawbacks of the conventional art, and it is possible to use both sides of a floppy disk with a magnetic recording/reproducing device incorporating a single-sided magnetic head. To provide a floppy disk cassette having a C2 configuration so that front and back sides can be discriminated.

In order to achieve the above-mentioned object, the present invention provides a predetermined position I of the cassette: one opening for index hole detection is provided on both the front and back, so that the cassette can be used upside down. is adopted.

Hereinafter, the present invention will be described in detail based on embodiments shown in the drawings.

Figure 2 (B) illustrates one embodiment of the present invention, and parts C that are the same as those in the first section to C) in the figure are given the same reference numerals.

In this embodiment, a force is applied between the opening 1C of the floppy disk cassette 1 and the display label 5, and the center of the opening 1D is connected to the inside of the opening IC at a position closer to the opening 1C. An opening 3 for detecting the index hole is provided on the line ≦2 I, z, and C2 is provided so that the index hole 4 can be detected on the line ≦2, and the floppy disk cassette 1 can be used upside down. If such a structure is adopted, it is not possible to use both sides of a .zeta.2 floppy disk cassette by using a device incorporating a single-sided magnetic head, which allows the use of both sides of the floppy disk.

The force 1 shown in Fig. 3 (B) is configured so that it can even detect the front and back sides.

In this embodiment, the opening 3 for detecting the index hole is provided at the same position as shown in FIG. With this structure, if detection means such as a bifurcated optical element and a light receiving element are provided to detect the index holes 4a and 4b, then A.
When a surface is used, as shown in FIG. C second, B side
, the order in which the signals are generated is reversed.

If the signal thus obtained is input to the D flip-flop circuit shown in FIG. 6, a side signal indicating which side is being used can be obtained.

In this example, when the A side is used, the signal is at a low level, and when the B side is used, the signal is at a high level. Further, as the index signal, either one of the detection signals of the index holes 4a and 4b may be used.

In this way, both the front and back sides of the floppy disk cassette can be used without providing only one opening for index detection, and it is also possible to detect which side is being used.

FIGS. 4(A) and 4(B) show two other embodiments of the present invention.

In this embodiment, index holes 4a and 4b having different sizes are provided along the rotational direction of the floppy disk 2 facing the index hole detection opening 3 provided in a part of the floppy disk force set. It is. In this example, 4a>4b.

These index hole detection mechanisms have a structure shown in FIG. That is, one side of the cassette (the bifurcated optical element 6 and the light receiving element 7 are arranged and made to face the index holes 4a and 4b).

On the other side C2 of the cassette, a concave mirror 8b is arranged facing the light projecting element 6, and on the light receiving element 7 side, a plane mirror 8 receives the reflection from the concave mirror 8b and guides the reflected light to the C bifurcated light element 7.
A is provided.

Such a structure C=more index hole 4a.

4b, a difference occurs in the amount of light received by the light receiving element 7, which appears as a voltage change. Therefore, it is possible to reliably detect which direction the floppy disk is rotating, that is, which side is currently being used.

FIGS. 8(A) to 1c) show the detection circuit and detection signal. The detection circuit has two comparators C1 and C2, and the output from the light receiving element 7 is sent to each comparator C1.
, C2's child terminals (two people are connected, and the reference voltage V is manually applied to one terminal side. Based on this circuit structure, if the light receiving element 7 (second index hole 4a, 4b is detected) , the voltage waveform at point a in FIG. 8(3) is as shown in FIG. 8fB). A1 indicates when the light source is large and the light receiving element is small, and A2 indicates when the light source is small and the light receiving element is large. When these signals are input to a comparator C1 set with a slice level S for detecting sides A and B, and a comparator C2 set with a slice level S1 for index detection, a side signal and an index signal are obtained, respectively.This side signal SD and index signal IN are shown in FIG. 8(C).

Note that in FIG. 8 CA), point b indicates the slice level for A and B plane detection, and point 0 indicates the slice level for index detection.

If such a detection method is adopted, the rotation method of the floppy disk will not be affected in any way.

As is clear from the above description (2), according to the present invention, by providing one opening for index hole detection, a device incorporating a single-sided magnetic head is used to read both sides of a floppy disk cassette. It has the excellent effect of being able to use the same method, and also being able to reliably and easily detect the exposed front and back sides.

[Brief explanation of the drawing]

This is to explain some embodiments of the invention, and FIG. 2 (At
, (B) is a plan view and a side view showing one embodiment of the present invention, FIG. 3 (A), (B) is a plan view and side view showing another embodiment of the present invention, and FIG. 4 (A ), (B) are plan views and side views explaining another embodiment of the present invention, and FIGS. 5(A) and CB) are index holes obtained by the embodiment shown in FIG. 3(A) al. A diagram showing the waveform of a detection signal. FIG. 6 is a block diagram of a floppy disk front/back detection circuit based on the signal shown in FIG. 5. FIG. 7 is an index hole detection mechanism according to the embodiment shown in FIG. 4. 8(A) to 8(C) are respectively a block diagram of the index signal processing circuit according to the embodiment shown in FIG. 4, an output waveform diagram, and a side signal and index signal sliced and waveform-shaped at a predetermined level. FIG. 1... Floppy disk cassette 2... Floppy disk 3... Index hole detection openings 4a, 4b.
... Index hole 6 ... Light emitting element 7 ... Light receiving element. Figure 3 Figure 5@1 Figure 6

Claims (1)

[Claims] (+1) One opening for detecting an index hole is provided in a part of a cassette containing a floppy disk, so that the cassette can be used even if it is turned upside down. Floppy disk cassette. (2) Two index holes facing the index hole detection opening are provided with different shapes or arrangements, and a potential difference or phase difference is generated in the detection signal by the index hole detection means C2. The floppy disk cassette according to claim 1, wherein the floppy disk cassette is configured to detect the front and back sides of the floppy disk cassette.