JPS606940Y2 - Disk cassette for recording and playback - Google Patents

Description

[Detailed Description of the Invention] In the present invention, a shutter is slidably attached to a flat cassette housing in which a disk-shaped recording medium is rotatably housed and has a head insertion hole, and the shutter is slid in a predetermined direction. In particular, the present invention relates to a recording/reproducing disk cassette configured such that the head insertion hole can be opened or closed.

FIG. 1 shows this type of conventional recording/reproducing disk cassette, in which a circular flexible magnetic disk 1 with a magnetic layer formed on one (or both) sides is arranged in a pair of upper and lower cassettes made of, for example, a plastic material. It is rotatably housed in a flat cassette housing 2 consisting of halves 2a*2b.

A recess 3 is formed in each of the upper and lower cassette halves 2a and 2b, and a long hole 4 for inserting a pad and a long hole 5 for inserting a head are provided at corresponding positions above and below these recesses 3, respectively.

Further, in the recess 3 of the cassette housing 2, a shutter 9 having a rectangular cross section and having an open lower opening 8 corresponding to the long holes 4 and 5, respectively, slides in the directions of arrows A and B in FIG. It is installed freely.

Although not shown, the cassette housing 2 is provided with a shutter guide section.

Then, the shutter 9 is slid in the direction of the arrow A to open the lower part of the shutter 9, and the shutter 9 is moved through the elongated hole 4 of the cassette housing 2.
When the disk cassette is mounted on a recording/reproducing device with the long holes 4 and 5 open, the magnetic disk 1 inside the cassette housing 2 is driven to rotate at high speed, and the long holes 4 and 5 are stacked on top of each other. A pad and a magnetic head (none of which are shown) are brought into contact with the magnetic disk 1 via the magnetic disk 5 to sandwich it.

The magnetic head is then moved in sliding contact with the magnetic disk 1 in the radial direction, thereby recording information on the magnetic disk 1 or reproducing information recorded on the magnetic disk 1.

Note that when the disk cassette is not in use, the shutter 9 is moved in the direction of arrow B and the long holes 4,
By closing the magnetic disk 5, it is possible to prevent inconveniences such as fingers or the like touching the magnetic disk 1 or dust adhering to the magnetic disk 1.

By the way, the shutter 9 used in conventional disk cassettes is made by bending a plate-like member made of stainless steel, aluminum, etc. into a box-shaped cross section, as shown in FIG. It is composed of a lower plate part 9a and an upper plate part 9b which face each other, and a connecting plate part 9c which connects these to each other at one end.

Note that the lower plate part 9a and the connecting plate part 9C are bent at almost a right angle, but the connecting plate part 9C and the upper plate part 9b are bent at an acute angle, so that they are not inserted into the cassette. In this state, the entire upper plate portion 9b is inclined toward the lower plate portion 9b.

The shutter 9 has such a configuration for the following reasons.

That is, the upper and lower cassette halves 2a and 2b of the cassette housing 2
is usually made of plastic (synthetic resin), and the cassette housing 2 is constructed quite flat, so the upper plate 11 and lower plate 12 of the cassette housing 2 are on the inside, as shown in FIG. It is easy to be curved and remain in that state.

Therefore, when the shutter 9 is configured to have a completely U-shaped cross section, when the shutter 9 is attached to the cassette housing 2, the tips of the lower plate part 9a and the upper plate part 9b are (open end) protrudes outward from the recess 3 of the cassette housing 2.

In this case, not only does the external appearance of the disc cassette become very unsightly, but also there are major inconveniences such as hands, clothes, etc. getting caught in this protruding part and causing damage.

In order to eliminate this inconvenience, conventionally, the shutter 9 is constructed as shown in FIG. 3, so that even if the cassette housing 2 is curved as shown in FIG. , 9b are directed inward toward each other so as not to protrude outward from the recess 3.

However, not all cassette housings 2 are curved as shown in FIG. 3, and some are not curved.

When the shutter 9 configured as shown in FIG. 2 is attached to the uncurved cassette case 2, the top plate portion 9b of the shutter 9 is moved by the top plate 11 of the cassette case 2 as shown in FIG. Since it is further energized and moved in the direction of arrow C than in the case, the gap at the portion indicated by the symbol α is narrowed.

As a result, the contact area between the upper plate part 9b and the upper plate 11 becomes larger, and the pressing force of the upper plate part 9b against the upper plate 11 becomes even stronger.

For this reason, the shutter 9 cannot be smoothly slid with respect to the cassette housing 2 with a relatively small sliding force.

In addition, the strongest pressure force is applied to point P, which is relatively closest to the bent portion 13 of the contact portion between the upper surface plate portion 9b and the upper plate 11 mentioned above, and furthermore, from the bent portion 13 Since the distance to point P becomes shorter, a considerably large pressure bonding force acts on the upper plate 11 from the upper plate 9b at this point P.

As mentioned above, the cassette housing 2 is made of synthetic resin with relatively low hardness, and the shutter 9 is made of stainless steel, which has relatively high hardness, so the cassette housing 2 corresponds to the point P by the shutter 9. There is a drawback in that the straight line part 1 (see Figure 1) has been shaved off, making it look very unsightly.

The present invention was devised in view of the above-mentioned actual situation, and it is possible to smoothly slide the shutter with respect to the cassette housing with a relatively small sliding force, and it is possible to move the shutter smoothly by sliding the shutter. It is an object of the present invention to provide a recording/reproducing disk cassette constructed so as not to damage the cassette housing.

An embodiment of the present invention will be described below with reference to FIGS. 5 to 9.

Note that in FIGS. 5 to 9, parts common to those in FIGS. 1 to 4 are given the same reference numerals and their explanations will be omitted.

As shown in FIG. 5, a disk cassette is composed of a circular flexible magnetic disk 1 and a cassette housing 2 made up of a pair of upper and lower cassette halves 2a and 2b welded together. The magnetic disk 1 described above is rotatably housed inside.

The magnetic disk 1 is, for example, a polyester film with a magnetic layer formed on the lower surface thereof.

Also, approximately in the center of this magnetic disk 1 is a circular opening 1.
A flange 17a of the dish-shaped core bar 17 is formed in the opening 16 using double-sided adhesive tape (not shown) or the like.
are integrally combined.

The above-mentioned core bar 17 is made of a magnetic material such as iron, and has a spindle insertion hole 18 in its center, and a rotary drive pin insertion hole 19 at a position remote from the insertion hole 18.

On the other hand, the upper cassette half 2a is provided with a long hole 4 for inserting a pad, and the lower cassette half 2b is provided with a long hole 5 for head insertion so as to correspond to the above-mentioned long hole 4.

Further, a circular opening 20 for inserting a rotational drive shaft is formed in the lower cassette half 2b, and a core metal 17 is provided within this opening 20.
The convex portion 17b is rotatably fitted into the convex portion 17b.

Furthermore, liner sheets 22 and 23 made of non-woven fabric or the like are interposed between the upper cassette half 2a and the magnetic disk 1 and between the lower cassette half 2b and the magnetic disk 1, respectively. 23 allows the magnetic disk 1 to rotate smoothly.

The liner sheet 22 is provided with a long hole 24 for inserting a pad, which corresponds to the long hole 4 of the upper cassette half 2a, and the liner sheet 23 is provided with a circular central opening 25 for inserting a spindle and a long hole of the lower cassette half 2b. Elongated holes 26 for head insertion corresponding to 5 are provided respectively.

When the disk cassette is installed in a recording/reproducing device (not shown), the rotary drive shaft 2 is rotated as shown in FIG.
At the same time, the center spindle 30 and the rotation drive pin 31 are inserted into the insertion holes 18 and 19 of the core bar 17, respectively.

As a result, the rotational driving force of the rotational drive shaft 28 is transferred to the core metal 17.
In turn, the signal is transmitted to the magnetic disk 1.

On the other hand, a tape pad (not shown) presses against the magnetic disk 1 via the elongated holes 4 and 24, and a magnetic head (not shown) presses against the magnetic disk 1 via the elongated holes 5 and 26, respectively, to hold it therebetween.

As the magnetic disk 1 is driven to rotate,
A magnetic head and a tape pad are moved in the radial direction of the magnetic disk 1 to perform predetermined recording or reproduction.

Furthermore, in the disc cassette of this embodiment, a shutter 34 is attached to the recess 3 provided in the cassette housing 2.

This shutter 34 is made by bending a single plate-like member made of stainless steel, aluminum, etc., and as shown in FIGS.
A first plate portion) 35, an upper plate portion (second plate portion) 36 facing substantially parallel to the lower plate portion 35, and these plate portions 35 and 36 are connected to each other at one end thereof. The connecting plate portion (third plate portion) 37 has a narrow width.

Therefore, the shutter 34 as a whole has a rectangular cross section.

Further, the above-mentioned upper surface plate portion 36b and lower surface plate portion 36a are provided with long holes 7 and 8 for inserting pads and magnetic heads, respectively.

In this embodiment, the above-mentioned upper plate part 36 includes a parallel plate part 36a whose one end is connected to the connecting plate part 37 and extends substantially parallel to the lower plate part 35, and this parallel plate part 36a. and an inclined plate part 36b which is bent at a central point 39 substantially parallel to the connecting part of the connecting plate part 37, that is, the bent part 38, and is inclined toward the lower surface plate part 35.

Note that the bent portions 38 at both upper and lower ends of the connecting plate portion 37
．． 40 has a nearly right angle shape.

Therefore, the distance between the inclined plate part 36b and the lower plate part 35 becomes gradually narrower as it approaches the open end from the bent part 39.

Further, the bent portion 39 in the upper plate portion 36 is linear as shown in FIG.

Although not shown in the drawings, the cassette housing 2 is provided with a guide section consisting of a guide groove or the like, and the shutter 34 is guided by this guide section.

If the shutter 34 having such a configuration is used, the shutter 34 can be placed in a preferable state regardless of whether or not the upper plate 11 and the lower plate 12 of the cassette housing 2 are curved. (In other words, it can be installed without damaging the appearance).

That is, even if the upper plate 11 and lower plate 12 of the cassette housing 2 are each curved inward as shown in FIG. Since the width between the lower plate part 35 and the inclined plate part 36b is narrow as described above, the amount of deformation of the upper plate 11 and the lower plate 12 in the thickness direction of the cassette housing 2 can be absorbed. .

Therefore, the above-mentioned shutter 34 can fully accommodate the curved cassette housing 2.

In this case, the bent portion 39 of the upper plate portion 36 of the shutter 34 will protrude somewhat from the recess 3 of the cassette housing 2, but even the open ends of the upper plate portion 36 and the lower plate portion 35 will not fit into the recess. As long as it does not protrude from point 3, the overall appearance of the disc cassette will not be spoiled.

Further, when the above-mentioned shutter 34 is attached to the recess 3 of the uncurved cassette housing 2 as shown in FIG. 9, the narrow open end of the shutter 34 is widened.

At this time, the entire surface of the lower plate portion 35 of the shutter 34 is lightly pressed onto the lower plate 12 of the cassette housing 2.

On the other hand, the upper surface plate portion 36 of the shutter 34 is elastically deformed around the bent portions 40 and 38, and as a result, the open end portion of the inclined plate portion 36 is pressed against the upper plate 11 of the cassette housing 2 by its elastic force. The parallel plate portion 36a of the upper plate portion 36 is slightly lifted from the upper plate 11 while being lightly crimped.

In this case, the gap indicated by the symbol β in FIG.
The contact area between the inclined plate part 36b of the shutter 34 and the upper plate 11 of the cassette housing 2 becomes larger as it becomes narrower than in the case shown in FIG. , the sliding force required to slide the shutter 34 is relatively light.

Furthermore, point Q, where the strongest pressure force acts among the contact portions between them, is far away from the bending portion 38 (ie, the center of rotation), so the pressure force is much weaker than in the past.

Therefore, the upper plate 11 of the cassette housing 2 corresponding to the Q point
There is no risk that the portion will be scraped off by the sliding movement of the shutter 34.

When this was confirmed through experiments, the following results were obtained.

The shutter 9 of the conventional structure and the shutter 34 of the embodiment were respectively attached to the same cassette casing, and the sliding force was measured, and this measurement was applied to a large number of cassette cassettes (including those without curves and those with curves). As a result, in the case of the shutter 9 of the conventional structure, it is 150 to 40
A sliding force of 0 g was required.

On the other hand, in the case of the shutter 34 of the example, the sliding force was 100 g or less for all the cassette cases.

Therefore, it has been confirmed through experiments that the shutter 34 of this embodiment can produce the effects described above.

Although the present invention has been described above with reference to one embodiment, the present invention is not limited to this embodiment, and various modifications and changes can be made based on the technical idea of the present invention.

As described above, the present invention provides a shutter to be attached to a cassette case, which includes a flat first plate part, a second plate part facing substantially parallel to the first plate part, and a shutter attached to the cassette case. and second
and a third plate part connected to each other at one end thereof, and the second plate part is bent at a point substantially parallel to the connecting part of the third plate part. A slanted plate portion is provided on the side of the first plate portion.

Therefore, since the inclined plate part is provided at the connecting part (bending part) of the second and third plate parts, that is, at a location far from the center of rotation of the second plate part, the recording/reproducing method of the present invention According to the disc cassette for use with the disc cassette, it is possible to adapt the shutter to a curved cassette housing, and even in the case of a non-curved cassette housing, the sliding force required to slide the shutter can be reduced. This makes it possible to achieve extremely smooth sliding movement, and it is also possible to reliably prevent a portion of the cassette casing from being scraped off by the shutter as the shutter slides.

[Brief explanation of drawings]

1 to 4 are for explaining a conventional recording/reproducing disk cassette. FIG. 1 is a perspective view of this disk cassette, FIG. 2 is a sectional view of the shutter, and FIG. 3 is a sectional view of the shutter. 1 is a sectional view taken along the line ■-■ in FIG. 1, and FIG. 4 is an enlarged sectional view of essential parts showing a state in which a shutter is attached to a non-curved cassette housing. 5 to 9 show an embodiment of the present invention, in which FIG. 5 is an exploded perspective view of a recording/reproducing disk cassette;
FIG. 6 is a sectional view showing the disk cassette installed in a recording/reproducing device, FIG. 7 is a sectional view of the shutter, and FIG. 8 is a sectional view showing the shutter attached to a curved cassette housing. FIG. 9 is an enlarged sectional view of a main part showing a state in which a shutter is attached to a cassette housing without curvature. In addition, in the symbols used in the drawings, 1...
・Magnetic disk, 2...Cassette case, 5...
...Elongated hole for head insertion, 8...Opening, 34
...Shutter, 35...Bottom plate part,
36... Upper surface plate part, 36a... Parallel plate part, 36b... Inclined plate part, 37... Connection plate part, 3B, 40, 41. ...Bending part, 39
......It is a bent part.

Claims (1)

[Scope of utility model registration request] A shutter is slidably attached to a flat cassette housing in which a disk-shaped recording medium is rotatably housed and has a head insertion hole, and the head insertion hole is opened or closed by sliding the shutter in a predetermined direction. In a recording/playback disc cassette configured to allow
The shutter includes a first plate portion having a flat plate shape, a second plate portion facing the first plate portion substantially parallel to the first plate portion, and one end of the first and second plate portions. and a third plate portion connected to each other at a portion thereof, and the second plate portion is bent at a location substantially parallel to the connecting portion of the third plate portion to form the first plate portion. A disc cassette for recording and reproducing, characterized in that it has an inclined plate portion that is inclined toward the side.