JPH058327A - Preparation of containment case for recording medium and blade for ruled line with stopper - Google Patents

Abstract

PURPOSE:To obtain an excellent containment case which does not produce non-conforming article caused by cutting of a ruled line section and has no scattering of strength and to finish a smooth curved condition by beveling well corners of the containment case. CONSTITUTION:When a raw material sheet is prepd. from a plastic flat sheet 36, a contour line is formed by punching and at the same time, a ruled line for bending is formed by providing a cut without heating. Stoppers 38 for adjusting a depth of cutting are provided on both sides of a blade for the ruled line. It is possible thereby to prevent the remaining section at the ruled line part from becoming too thin. In addition, vicinities of parts where the front faces 42 of the stoppers 38 are brought into contact with the blade 34 for the ruled line are curved respectively in the direction departing from the blade 34 for the ruled line. Therefore, both edges of a cut groove forming a ruled line can be curved respectively.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a storage case for a recording medium such as a tape cassette or a floppy disk, and more particularly to a method for manufacturing a material plate and a ruled blade with a stopper used in the method.

[0002]

2. Description of the Related Art Conventionally, tape cassettes for audio, video, etc. are stored in a case made of plastic, paper, etc. for protection. If the surface of a recording medium such as a magnetic tape is dusty or the surface is scratched, the recording will be lost and erroneous recording or erroneous display will occur. Therefore, the storage case protects the tape cassette against transportation and storage, and after the consumer purchases it, puts it in and out and puts it in use. There is.

When assembling a sleeve type storage case as such a storage case, the following steps are usually taken. First, a large plastic flat plate is prepared, and the surface thereof is printed. Then, using a machine equipped with a sharp cutting blade for punching, a plastic flat plate is placed on the surface plate, the cutting blade is pushed down, and many material plates of the storage case are taken at a time. At that time, each material plate is cut from a plastic flat plate along the contour line of the development view of the storage case and punched.

Next, using a machine having a die and a platen on which a thick blade for pushing a muscle is installed for each sheet (one sheet) of these material plates, these blades and platen are Each is heated, the thick blade is pushed down, pressed against the surface of the material plate placed on the surface plate, and the groove is formed by performing the muscular pressing by the heat press. Therefore, a folding ruled line in the development view of the storage case is formed on the material plate.
Then, the material plate is put into a can-making machine, and predetermined portions are overlapped and welded while being bent, whereby a completed storage case is obtained.

However, even if a large number of material plates of the storage case are punched out from such a plastic flat plate at a time, if the muscles are pushed for each of the individual sheets thereafter, the burden is large and the work efficiency is poor and the product is expensive. It becomes a thing. Therefore, it is conceivable to punch and press the plastic plate at the same time. However, when the pressing is performed by hot pressing, heat is applied to the plastic material to soften and press the plastic material, so that expansion occurs in both directions near the pressing groove and the reaction groove of the material plate. Moreover, since the periphery of the material plate is regulated by a cutting blade or the like for punching, there is no place for the elongation to escape. As a result, the muscle pushing point is distorted, the dimensions are incorrect, and the deformation remains after cooling, which causes the case to be distorted.
The appearance quality is inferior.

Therefore, the present applicant has previously filed Japanese Patent Application No. 2-316.
As No. 662, when a material plate corresponding to the shape of the development view of the storage case for the recording medium is manufactured from a plastic flat plate, the flat plate is punched to form the contour line of the material plate, and at the same time, the flat plate is not heated. We have proposed a method of manufacturing products with excellent external appearance with good work efficiency and at low cost by adopting the process of making a notch of the required depth in the thickness direction and forming the folding ruled line of the material plate. .

At present, the cutting depth of such a folding ruled line is determined by punching out the machine, removing unevenness (the height adjusting portion of the cutting blade and the ruled line blade) provided on the back side of the cutting die, and pressing down the cutting die. I am adjusting. FIG. 11 is a front view showing a correspondence relationship between a cutting blade installed in a punching and cutting type, a ruled line blade and a plastic flat plate, and a cut state.
FIG. 6 is a perspective view showing a cut state of the ruled line blade and the plastic flat plate. In the figure, 10 is a punch, notch type, 12
Is a main body thereof, 14 is a cutting blade provided therein, 16 is a ruled line blade, 18 and 20 are uneven blades of the blades 14 and 16, and 22 is a chess board. To remove these irregularities 18, 20 are provided pawls such as tape, paper, aluminum plate, etc. in the respective support holes formed in the chess board 22, and the height of each blade 14, 16 (protrusion length downward from the main body 12). ) Respectively. Again 2
Reference numeral 4 is a large flat plate made of plastic, 26 is a cut portion thereof (outline of the material plate), and 28 is a cut groove (ruled line for bending the material plate). In addition, 30 is a reaction groove.

[0008]

However, when the plastic flat plate 24 is punched and cut using the punching and cutting die 10 in this manner, the thickness of the flat plate 24 and the machine are adjusted, and the cutting blade 14 is cut. Due to variations in durability (the degree of reduction of the cutting edge) and the like, the thickness between the cut groove 28 and the reaction groove 30 of the flat plate 24, that is, the residual thickness, tends to be thick or thin. If the thickness becomes larger than the standard residual meat, the can-making machine will become clogged or the adhesiveness will become a problem.
On the contrary, as the thickness decreases, it becomes easier to cut at the cut groove 28. If even a part of the ruled line portion is cut during bending, the storage case becomes a defective product, so it is more important to prevent the ruled line portion from being cut off.
On the other hand, if it is too thin, the strength will be poor and the storage case will be easily damaged during use. The cut groove 28
Since both edges are in a right-angled state, the ink printed on them is easily scraped off and the packaged film is also easily torn.

The present invention has been made in view of such conventional problems, and is for an excellent recording medium in which no defective product is generated due to the cutout of the folding ruled line portion and the strength does not vary. An object of the present invention is to provide a manufacturing method for obtaining a storage case, and a ruled line blade for chamfering a corner portion of the storage case to finish a smooth curved surface.

[0010]

In order to achieve the above object, in the method of manufacturing a storage case for a recording medium according to the present invention, a plastic flat plate 36 to a storage case 60 for a recording medium are used.
When manufacturing the material plate 50 corresponding to the shape of the developed view, the flat plate 36 is punched to form the contour line 52 of the material plate 50, and at the same time, a notch of a required depth is formed in the thickness direction of the flat plate 36 without heating. By performing the step, the ruled line 48 for bending the material plate 50 is formed. Then, the ruled line blade 34 forming the ruled line 48 is provided with stoppers 38 on both sides thereof for adjusting the cutting depth.

Further, it is preferable that the front surface 42 of the stopper 38 has a rounded shape in the vicinity of the contact point with the ruled line blade 34 in the direction away from the ruled line blade 34.

[0012]

If the stopper 38 for adjusting the cutting depth is provided on both sides of the ruled line blade 34 in the above-described structure, the front surface 42 of the stopper 38 acts as an obstacle at the time of cutting. Therefore, the cutting depth can be maintained at the distance between the front end of the ruled line blade 34 and the front surface 42 of the stopper 38, which is set in advance. In particular, if the pressing force of the punching / cutting die is set to be slightly higher, the material plate 50 is satisfactorily punched from the plastic flat plate 36, and it becomes easy to keep the cutting depth of the ruled line 48 constant. Further, as ruled line blades, objects having various cutting edge shapes can be used. Naturally, when a blade having a sharp edge is used, the cutting becomes easy, and the expansion to both sides generated at the time of the cutting becomes small, and the expansion easily returns to the original state when the blade is removed.

Further, the ruled line blade 3 on the front surface 42 of the stopper 38
When the vicinity of the contact point with 4 is rounded in the direction away from the ruled line blade 34, both edges 49 of the cut groove 44 forming the ruled line 48 are rounded, so that the corner portion 62 when bent is also excellent. Chamfered to give a smooth curved surface. For this reason, the appearance of the storage case 60 becomes excellent, the ink printed on it cannot be removed even by rubbing, and the packaged film or the like does not tear.

[0014]

Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a perspective view showing a state in which a plastic flat plate is cut by a ruled blade with a stopper installed in a punching and cutting type provided in a material plate manufacturing machine for a sleeve type storage case for a tape cassette to which the present invention is applied. FIG. 2 is a perspective view showing a state before cutting, and FIG. 3 is a perspective view showing a state after cutting. In the figure, 32 is a punching / cutting type equipped on a machine, 34 is a ruled blade with a stopper having a rectangular parallelepiped shape which is installed at a predetermined position, and 36 is a large plastic flat plate made of polypropylene, polyethylene terephthalate or the like. The ruled line blades 34 are integrally formed with the stoppers 38 on both sides to be formed symmetrically, and only the blade tip portion 40 thereof projects from the center of the lower surface along the longitudinal direction. The cutting edge portion 40 is thin, and a large curved surface is provided at the tip. Further, the punching / cutting die 32 is provided with a cutting blade (not shown) for punching, the tip of which projects at an acute angle at another predetermined position. In addition, if the ruled line blade 34 and the stopper 38 are integrally manufactured, readjustment of the ruled line blade 34 due to wear of the cutting blade can be performed in the same manner as the current unevenness removing work.

The front surface of the stopper 38, that is, the surface 42 of the ruled line blade 34 which faces the cutting edge direction is arranged at a right angle to the protruding direction of the cutting edge portion 40 to widen the area. Then, the front surface 42 becomes an obstacle to the notch for the plastic flat plate 36. Therefore, the front surface 42 of the stopper 38 and the cutting edge portion 40
The depth of cut can be adjusted by the distance L between the tips. Therefore, the distance L is first set in consideration of the depth of the reaction groove.
Further, the front surface 42 of the stopper 38 is rounded in the vicinity of its contact point with the ruled line blade 34 in the direction away from the ruled line blade 34 to the left and right. Incidentally, the stopper may be provided in the punching type, the cutting type or the equipment itself, but it is convenient to provide the stopper for each ruled line blade because the cutting depth can be adjusted individually.

When forming the material plate of the sleeve type storage case, first, as shown in FIG. 2, a plastic flat plate 36 is placed on a surface plate (not shown). Next, punch, notch type 3
Oil pressure is applied to 2 to push down each ruled line blade 34 and the cutting blade without heating. Then, as shown in FIG. 1, a cutting groove 44 for forming a ruled line is formed on the upper surface of the plastic flat plate 36 by the cutting edge portion 40 of the ruled line blade 34. At the same time, a reaction groove 46 is formed on the lower surface. Therefore, the hydraulic pressure is reduced to raise the ruled line blades 34 as shown in FIG. Then, the stopper 38
Since the front surfaces 42 of the cut grooves 44 are rounded, both edges 49 (49a, 49b) of the cut groove 44 are also rounded.

In this way, as shown in FIG. 4, for example, six material plates 50 are taken from the plastic flat plate 36. At that time, each material plate 50 as shown in FIG. 5 is cut and punched by the cutting blade along the contour line 52 of the development view of the storage case. At the same time, a ruled line 48 for folding the development view of the storage case is formed on each material plate 50 by cutting the ruled line blade 34. In addition, the punching and cutting die 32
By slightly increasing the pressing force of, the material plates 50 are satisfactorily punched out from the plastic flat plate 36, and it becomes easy to keep the depth of cut of the ruled lines 48 constant.

Since each of these material plates 50 has the shape of the development view of the sleeve type storage case, the ear flaps 54 (5)
4a, 54b), the front flap 56 (56a, 56b),
The back flap 58 (58a, 58b) and the like are provided. Therefore, when the tape is accommodated in a can making machine (not shown), the corresponding flaps are appropriately overlapped while being bent, and both side plates are welded to form a sleeve type case for storing a tape cassette as shown in FIG. 60 is completed.

In such a sleeve type storage case 60, since both edges 49 of each ruled line 48 in the material plate 50 are rounded, each corner portion 62 when bent is also smoothly chamfered and has a smooth curved surface. Finished in a shape. Therefore,
The appearance is excellent, the ink printed on the corners 62 cannot be removed by rubbing, and the packaged film or the like is not broken. If the front surface of the stopper is slightly tapered in the direction away from the ruled blade, it can be made inconspicuous as a scratch even if excessive pressure is applied. Furthermore, it is advisable to chamfer both edges of the front surface in order to prevent pressure damage.

FIG. 7 is a schematic view showing a blanking machine equipped with a similar blanking machine.
It is a perspective view which shows the other ruled line blade with a stopper installed in the cutting type. This machine also has a ruled blade 66 with a stopper at a predetermined position of the punching and cutting die 64 on the upper side,
A cutting blade (not shown) is installed, and a surface plate (not shown) is installed on the lower side.
Is equipped with. Therefore, by punching and cutting at the same time, it is possible to take out a large number of similar material plates of the sleeve type storage case from the plastic flat plate. However, the ruled line blade 66 and the stoppers 68 (68a, 68b) on both sides thereof are separate bodies. Incidentally, the stopper 68 is naturally harder than the flat plate made of plastic.

When the stoppers 68 are provided on both sides of the ruled line blade 66 in this way, and these stoppers 68 are removed and attached to the lower surface of the cutting die 64, each stopper 68 can be slid with respect to the cutting edge direction of the ruled line blade 66. The structure of
The positions of the front surfaces 70 (70a, 70b) can be adjusted appropriately. Therefore, an appropriate cutting depth is set according to the thickness and material of the plastic flat plate used. After that, the ruled line blade and the stopper may be integrally manufactured based on the obtained numerical values. In addition, each stopper 68
Is preferably provided continuously rather than partially attached to the ruled line blade 66.

FIG. 8 shows a punch equipped with a similar material plate manufacturing machine.
It is a perspective view which shows the other ruled line blade with a stopper installed in the cutting type. Also in this case, the ruled line blade 72 and the stoppers 74 (74a, 74b) on both sides are separate bodies. However, the bases of both stoppers 74 along the ruled line blade 72 are continuously punched out and penetrate the cutting die 76.

FIG. 9 shows a punch equipped with a similar material plate manufacturing machine,
It is a perspective view which shows the other ruled line blade with a stopper installed in the cutting type. Also in this case, the ruled blade 78 and the stoppers 80 (80a, 80b) on both sides are separate bodies. However, the base parts of both stoppers 80 are partially removed,
The cutting die 82 is penetrated.

In each of the above-mentioned embodiments, the blade edges of the ruled line blades are all thin blades and the curved surface of the tip is large. However, since the blades are provided with stoppers, various blade tips can be used. For example, as shown in FIG. 10, the tip is flat, has a small curved surface, or has a sharp projection. Needless to say, the sharper the blade edge is, the easier it is to make a cut, and the extension to both sides generated at the time of cutting is also small. The extension easily returns to the original state when the blade tip is pulled out.

[0025]

According to the present invention described above, since the stoppers for adjusting the cutting depth are provided on both sides of the ruled line blade, it is possible to prevent the remaining thickness of the ruled line portion from becoming too thin. Therefore, a defective product due to the cutout of the ruled line portion does not occur, and an excellent storage case for a recording medium having no variation in strength can be obtained.

Further, when the vicinity of the contact point with the ruled line blade on the front surface of the stopper is rounded in the direction away from the ruled line blade, both edges of the cut groove forming the ruled line are rounded, so that the recording medium is stored. The corners of the case are well chamfered to give a smooth curved surface. Therefore,
The appearance of the storage case for the recording medium becomes excellent, the ink printed on the storage case cannot be removed even by rubbing, and the packaged film or the like does not break.

[Brief description of drawings]

FIG. 1 is a perspective view showing a state in which a plastic flat plate is cut by a ruled blade with a stopper installed in a punching / cutting type provided in a material plate manufacturing machine for a sleeve type storage case for a tape cassette to which the present invention is applied. It is a figure.

FIG. 2 is a perspective view showing a state before cutting by the ruled line blade with the stopper.

FIG. 3 is a perspective view showing a state after cutting by the ruled line blade with the stopper.

FIG. 4 is a perspective view showing a state in which a large number of the material plates are taken from a plastic flat plate.

FIG. 5 is a perspective view showing the same material plate.

FIG. 6 is a perspective view showing a completed assembly state of the sleeve type storage case.

FIG. 7 is a perspective view showing a ruled line blade with a stopper for manufacturing a material plate of a sleeve type storage case for another tape cassette to which the present invention is applied.

FIG. 8 is a perspective view showing a ruled blade with a stopper for manufacturing a material plate of a sleeve type storage case for another tape cassette to which the present invention is applied.

FIG. 9 is a perspective view showing a ruled line blade with a stopper for manufacturing a material plate of a sleeve type storage case for another tape cassette to which the present invention is applied.

FIG. 10 is a front view showing various blade tip shapes of the ruled line blade with a stopper.

FIG. 11 is a front view showing a correspondence relationship between a cutting blade installed in a blanking and cutting die provided in a material manufacturing machine for a sleeve type storage case for a tape cassette, a ruled line blade, and a cutting and cutting state of a plastic flat plate. .

FIG. 12 is a perspective view showing a cut state of the ruled line blade and a plastic flat plate.

[Explanation of Codes] 32, 64, 76, 82 ...
6, 72, 78 ... Ruled blade 36 ... Plastic flat plate 38, 68, 74, 80 ...
Stopper 40 ... Blade edge 42 ... Front of stopper
44 ... Notch groove 46 ... Reaction groove 48 ... Bending ruled line
49 ... Edge of notch groove 50 ... Material plate 52 ... Contour line
60 ... Sleeve type storage case for tape cassette 62 ...
Corner

Claims (2)

[Claims] 1. When manufacturing a material plate corresponding to the shape of a development view of a storage case for a recording medium from a plastic flat plate,
For a recording medium, in which the flat plate is punched to form the contour line of the blank plate, and at the same time, a notch of the required depth is made in the thickness direction of the flat plate without heating to form the folding ruled line of the blank plate. A method of manufacturing a storage medium storage case, characterized in that stoppers for adjusting a cutting depth are provided on both sides of a ruled line forming the ruled line. 2. A ruled line blade with a stopper, characterized in that the vicinity of the contact point with the ruled line blade on the front surface of the stopper is rounded in the direction away from the ruled line blade.