JPH04189786A - Holising case for recording medium and manufacture thereof - Google Patents

Abstract

PURPOSE:To manufacture a housing case for recording medium with an excellent appearance grade, with a favorable work efficiency and cheap cost by a method wherein a score process is used by applying a notch with a specified depth in the thickness direction of a sheet without heating, using a blank for which a contour line is punched from plastic flat sheet, and folding lines are applied by a score process to form a spraed-out sketch of the case. CONSTITUTION:Each bland 38 is cut and punched by a cutting blade along a contour line 40 of a spread-out aketch for a housing case. At the same time, on each blank 38, score process is applied along folding lines 42 of the spread- out sketch for the housing case by a notching blade 30. This score process is cutting which is performed in the thickness direction of the sheet without heating, and at a symmetrical location of the grooves 44 on the rear suuface, reaction grooves 46 are also formed. For the notching blade 30, a thin blade is used to make it easier to place a notch on a plastic flat sheet 36. The notching blade 30 is equipped with a flat surface 32 at the leading end to prevent the notch from becoming extremely sharp. By this method, cut off spots are not generated, and the adjustment for.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a storage case for recording media such as tape cassettes and floppy disks, and a method for manufacturing the same.

2. Description of the Related Art Traditionally, audio and video tape cassettes are protected by being stored in plastic, paper, or other cases when not in use. When a recording medium such as a magnetic tape has dust attached to its surface or is scratched, records may be lost and erroneous recording or display may occur. Therefore, it is necessary to prevent such occurrences. Therefore, before the storage case reaches the consumer, it protects the stored tape cassette from transportation and storage, and after the consumer has purchased it, the tape cassette can be taken out and put in for use. Furthermore, the structure has been designed with consideration given to workability.

To assemble such a storage case, for example, a sleeve-type storage case, first a large plastic flat plate is prepared. Then, using a mold 10 with cutting blades 12 for punching each having an acute angle protruding tip disposed at a predetermined location of the mold 10 as shown in FIG.
Each cutting blade 12 is placed on a plastic flat plate 14 placed on the
Push down in the direction of the arrow and remove many material plates from the storage case at once. For example, as shown in FIG. 7, six material plates 16 are taken. At that time, each material plate 1 as shown in FIG.
6 are cut and punched from a flat plastic plate 14 along the outline 18 of the developed view of the storage case.

Next, for each of these raw material plates 16 (one sheet), a mold having a thick blade 20 with a flat tip and a surface plate 22 as shown in FIG. 150″C1 surface plate 2
2 to 90°, push down the thick blade 20 in the direction of the arrow, press it against the surface (outer surface) of the material plate 16 placed on the surface plate 22, apply creases with a hot press to form grooves 24, and bend. make it easier At this time, a shallow groove 26 is formed on the back surface of the material plate 16 at a corresponding position due to the reaction. Incidentally, in the case of a flat paper plate, grooves are formed on the surface due to creasing, and ridges are formed on the back surface. In this way, the bending line 28 of the developed view of the storage case as shown in FIG. 10 is formed on each blank plate 16. Note that surface printing is also performed for each sheet. Therefore, the blank plate 16 is put into a can making machine, and while being bent, predetermined parts are overlapped and welded to obtain a completed storage case.

Problems to be Solved by the Invention However, such a large plastic flat plate 1
Even if a large number of storage case material plates 16 are punched out at one time from 4, if each sheet is then stamped and printed, it is a heavy burden and the work efficiency is poor, and the product becomes expensive. Become. Therefore, it is conceivable to perform punching and creasing simultaneously on the large plastic flat plate 14.

However, when creasing is performed using a heat press, the plastic material is heated and softened before being pressed, so as shown in FIG. Elongation occurs in the direction of the arrow.

Moreover, the periphery of the material plate 16 is restricted by the cutting blade 12 for punching, etc., and there is no place for the elongation to escape.

As a result, the creases are distorted and dimensional errors occur, and the deformation remains even after cooling, resulting in a distorted case and poor appearance quality.

The present invention has been made in view of these conventional problems, and it is an object of the present invention to provide a method for manufacturing a storage case for recording media with excellent appearance quality at a high work efficiency and at a low cost.

Means for Solving the Problems Means for achieving the above object will be explained below with reference to FIGS. 1 and 2, which correspond to embodiments.

This storage case for recording media is made by using a material plate 38 which is produced in the form of a developed view of the case by punching out contour lines 40 from a flat plastic plate 36 and stamping the bending lines 42. Then, as the creasing, cuts 44 of a required depth are made in the thickness direction of the plate without heating.

Moreover, as a method for manufacturing the storage case, punching and creasing are performed simultaneously.

Furthermore, a thin blade 30 having a flat surface 32 or a curved surface at the tip is used for the above-mentioned creasing.

Effect When configured as described above, and when the cut 44 of the required depth is made in the thickness direction of the plate as a crimp without heating, no heat is applied to the plastic flat plate 36, so naturally distortion due to heat will occur. Therefore, the bending portion 42 can be accurately cut. Therefore, processes such as bending, overlapping, welding, etc. necessary for subsequent can manufacturing can be performed accurately. Moreover, since plastic material is used, it is stronger than paper even though it is thinner, and it does not absorb moisture from the cut points 40 and notches 42.
suitable for use.

Furthermore, if punching and creasing are performed at the same time, it is convenient because the plastic flat plate 36 can be handled as a large size and can be subjected to processing such as printing as a pre-process. Moreover, from the large plastic flat plate 36, a plurality of blank plates 38 having a plurality of bending lines 42 are punched out at once in the shape of a developed view of the case.

Furthermore, when the thin blade 30 having a flat or curved tip is used, it is easy to cut into the plastic flat plate 36 because of the thin blade, and there is little elongation on both sides, and when the blade is pulled out, the plastic material inherently has the same properties as the plastic material. Due to its elasticity, it can easily return to its original state. Furthermore, since the tip has a flat surface 32 or a curved surface, it is possible to prevent extremely sharp cuts, and even if the cut is made deeply, no cut points occur, making it easy to adjust the depth.

Example Hereinafter, the present invention will be described in detail based on the accompanying drawings.

FIG. 1 is a partial perspective view showing the process of manufacturing a material plate for a sleeve-type storage case for tape cassettes to which the present invention is applied. In the figure, 30 is a cutting blade for thin creasing having a flat surface 32 at the tip, which is disposed at a predetermined location of the mold, and 34 is a surface plate made of an iron plate of the mold. This mold is equipped with a cutting blade for punching, the tip of which projects at an acute angle, at another predetermined location. Therefore, polypropylene (P
P), a large plastic plate made of polyethylene terephthalate (PET), etc. is placed, and each cutting blade 30. By pressing down on the cutting blade, you can remove many material plates from the storage case at once. For example, as shown in FIG. 2, six blank plates 38 can be taken from a plastic flat plate 36. that time,
Each material plate 38 as shown in FIG. 3 is cut and punched by a cutting blade along the contour line 40 of the developed view of the storage case. At the same time, the cutting blade 30 is placed on each material plate 38.
Stretching is performed along the bending line 42 of the developed view of the storage case. Note that if punching and creasing are performed at the same time, the plastic flat plate 36 can be handled as it is and printing can be performed as a pre-process, thereby improving work efficiency.

This creasing is a cut made in the thickness direction of the plate without heating, and a reaction groove 46 is also formed at a symmetrical position on the back surface of the groove 44. The depth of the cut groove 44 is varied depending on the thickness and material of the plate. The thickness of the plate is 350μ
m to 1000 μm, but if the depth of the cut is small, the case tends to return and become drum-shaped. Therefore, a thin blade is used for the cutting blade 30 to make it easier to cut into the plastic flat plate 36. Furthermore, when the blade is made thinner, the stretching to both sides that occurs when making a cut will be slight, and when the blade is handled, it will easily return to its original state due to the inherent elasticity of plastic. Further, the cutting blade 30 is provided with a flat surface 32 at the tip to prevent the cutting from becoming extremely sharp. Therefore, even if the cut is made as deep as 50% to 90% of the thickness, no cut points will be generated, and the depth can be easily adjusted. By the way, polypropylene is not only inexpensive, but also highly durable against temperature.
No cutting occurs due to stiffness at the bending point at low temperatures, making it suitable for use as a flat plate material.

When the cuts are made in the thickness direction of the plate as a crimp in this way, no heat is applied to the plastic material, so naturally no distortion occurs due to heat, and the cut grooves 44 are precisely placed at the bending points 42.
can be formed. Then, the subsequent processes such as bending, overlapping, and welding required for can manufacturing can be performed accurately, resulting in a good finish. In addition, since the material plate 38 has the shape of the developed view of the case, the ear flaps 48 (48a, 48b), the front flaps 50 (50a, 50b), and the back flaps 52 (
52a, 52b>, etc. Therefore, by placing the tape in a can making machine (not shown), folding it, overlapping the corresponding flaps as appropriate, and welding them together to form both side plates, a sleeve-like shape for storing tape cassettes as shown in Fig. 4 was created. Case 54 is completed.

Since this storage case 54 is made of plastic material, it is stronger than paper even though it is thinner, and it does not absorb moisture from the cut points 40 and cut points 42, making it suitable for use.

Note that on the opening sides of the front and back plates 56 and 58, notches 60 (60a, 60b) are provided on both edges for hooking fingers to tape cassettes (not shown) stored therein.

FIG. 5 is a partial perspective view showing the process of manufacturing a material plate for another sleeve-type storage case for tape cassettes to which the present invention is applied. This mold is also provided with a cutting blade 62 for pressing and a cutting blade (not shown) for punching at predetermined locations on the upper side, and a surface plate 64 on the lower side. Therefore, by performing punching and creasing at the same time, a large number of storage case material plates 66 can be similarly removed from a plastic flat plate. At this time, since the cutting blade 62 is a thin blade with a curved surface 68 at its tip and a thinner body, it becomes easy to cut into the -layer, and the depth can also be easily adjusted.

According to the present invention, which has been described in detail, only by making cuts in the plastic flat plate without applying heat, accurate creasing can be performed without causing distortion due to heat. Therefore, it is easy to carry out the subsequent can manufacturing process accurately, the finish is good, and a product with excellent appearance quality can be obtained. Moreover, since it is made of plastic material, it is strong and does not absorb moisture, making it suitable for use.

In addition, by performing punching and creasing simultaneously, these pre-processes can be performed on a large plastic flat plate, and many blanks can be manufactured at once in the shape of a case development, improving work efficiency. will improve and products will become cheaper.

Furthermore, if a thin blade with a flat or curved tip is used,
This is advantageous because it is easy to cut into a plastic flat plate, and the depth can be easily adjusted without leaving any deformation.

[Brief explanation of drawings]

FIG. 1 is a partial perspective view showing the simultaneous punching and creasing process for producing a blank plate for a sleeve-type storage case for tape cassettes to which the present invention is applied. FIG. 2 is a perspective view showing a state in which a large number of the same raw material plates are taken from a plastic flat plate, and FIG. 3 is a perspective view showing the same raw material plates. FIG. 4 is a perspective view showing the sleeve-type storage case in an assembled state. FIG. 5 is a partial perspective view showing the simultaneous punching and creasing process for manufacturing a blank plate for another tape cassette storage case to which the present invention is applied. FIG. 6 is a front view showing a mold for punching a material plate of a conventional sleeve-type storage case for tape cassettes from a flat plastic plate. FIG. 7 is a perspective view showing a state in which a large number of the same raw material plates are punched out from a plastic flat plate, and FIG. 8 is a perspective view showing the same raw material plates. Fig. 9 is a partial perspective view showing the creasing process for producing the material plate for the sleeve type storage case, Fig. 10 is a perspective view showing the same material plate, and Fig. 11 shows the condition of the same material plate during the creasing process. FIG. 30.62... Cutting blade 32... Plane 36...
Plastic flat plate 40...Contour line 42...Bending line 44...Notch 68...Curved surface Patent applicant T.D.K. Co., Ltd. Agent Patent attorney Dai Yanagisawa Work No. 1 (2) 60 cuts Blade 32 flat surface 34 surface plate filter 8 material plate 44 depth of cut 46 reaction groove 36 plasti, resin flat plate 38 material plate 40 contour line 42
Bending line Figure 3 38 Laminated wood board 40 Contour line 42 Bending line 48 Ear flap,
50 table hula 7. 52 back side flat, 54 sleeve type storage case 56.58 positive, back plate 60
Finger rests are notched Fig. 5 62 Cutting blade 64 Surface plate 66 Curved plate 68 Curved surface Fig. 7 Fig. 8 Fig. 9 Fig. 2 Fig. 10

Claims (3)

[Claims] (1) In a storage case for recording media that uses a material plate manufactured by punching out the outline from a plastic flat plate and creasing the bending lines to create the shape of the case's developed view, the creasing is performed without heating. A storage case for recording media, characterized in that a cut is made to a required depth in the thickness direction of the board. (2) The method for manufacturing a storage case for a recording medium according to item 1, characterized in that punching and creasing are performed simultaneously. (3) The method for manufacturing a storage case for a recording medium according to item 2, wherein a thin blade having a flat or curved tip is used for the creasing.