JPH0711907B2 - Disco Cartridge - Google Patents

Description

The present invention relates to a disc cartridge in which a disc is rotatably housed in an outer cover having a liner lined therein, and an improvement is made to a form of attaching the liner to the outer cover. . The disk is a concept that broadly includes magnetic disks and optical disks.

[Conventional technology]

For example, FIG. 2 illustrates a conventionally known magnetic disk cartridge (a so-called floppy disk), in which a disc is placed inside a jacket A in which a flexible outer cover 2 is lined with a non-woven liner 1. -Shaped magnetic disk 3 is rotatably enclosed, and a head window 4, a central window 5, an index hole 6 and the like are punched and formed in the jacket A.

FIG. 3 is a development view of the jacket A, in which the whole of the thermoplastic synthetic fiber non-woven liner 1 is partially shown on the inner surface of the outer cover 2 made of vinyl chloride or its copolymer sheet. The peripheral edges of the opening of the non-woven fabric liner 1 which are spot heat-welded and face the head window 4, central window 5 and index hole 6 are designated by P ₁ and P _2.
・ As shown by P ₃ , heat welding is performed in an annular pattern with a high welding density. Such a form in which the portions indicated by the symbols P ₁ , P _2, and P ₃ are heat-welded with a constant width is known in Japanese Patent Publication No. 58-56170. When the entire non-woven fabric liner 1 is partially heat-welded and lined on the outer cover 2, instead of spot heat-welding in the illustrated example, heat-welding may be performed using an appropriate linear pattern or the like.

More specifically, after the non-woven liner material is heat-welded to the outer cover material in the same manner as described above, the outer cover material is trimmed and the head window 4 and the like are punched and cut into the developed state shown in FIG. Is made.

As the non-woven liner 1, a non-woven fabric in which 80% rayon fiber and 20% polypropylene fiber are mixed is generally used. However, this non-woven fabric liner containing polypropylene fibers is difficult to wear and has poor durability.

Therefore, in order to improve this point, it has been proposed by the present applicant to use a non-woven fabric containing polyester fiber having excellent abrasion resistance in place of the conventional polypropylene fiber, for example, a non-woven fabric in which polyester fiber and rayon fiber are mixed. Proposed earlier. Japanese Patent Application No. 60-49436 is that.

[Problems to be solved by the invention]

In this kind of disc cartridge, head window 4, central window 5 and index hole 6
At the periphery of the non-woven fabric, the non-woven fabric liner 1 is densely heat-welded to the outer cover 2 as indicated by the symbols P ₁ , P _2, and P ₃ because the fibers of the non-woven fabric liner 1 are frayed, that is, the fluffs emerge. This is to prevent This prevention of fluffing is strongly required especially around the head window 4.

A problem with such a conventional example is that when the non-woven fabric liner 1 is densely heat-welded to the outer cover 2 under the heat and pressure around the head window 4, remarkable welding marks are generated on the outer cover 2 side. This is a point that the external shape is deteriorated to give an image of a poor product, and in fact, the rotation performance of the disk 3 is seriously adversely affected. That is, when attention is paid to the spot heat-welding portion P in FIG. 1, it is also known from the fact that a welding mark is largely present on the outer cover 2 side and has an uneven shape. However, since the spot heat welding is limited to a small area due to the partial spot heat welding, it is only allowed when limiting this.

Further, when the above-described non-woven fabric liner made of polypropylene fiber is used, the cuttability is good, so that the fluff can be prevented relatively well. However, when the above-mentioned polyester fiber-based non-woven liner is used to improve wear resistance, the elastic modulus is high and the shear strength is too high. I have a problem to do. In addition, since the polyester fiber has a high melting point, even if the generated fluff is burned off instantaneously with a flame, new thermal deformation occurs up to the opening peripheral edge of the vinyl chloride outer cover 2 having a lower melting point. They tend to get it.

[Object of the Invention]

Focusing on such a fact, the present invention has a basic object to prevent fluff from coming out from the liner 1 lined around the head window 4 which is a particularly problematic part of the opening provided in the outer cover 2.

Further, a specific object of the present invention is to prevent the outer cover 2 from being deformed and prevent the fluff from coming out of the liner 1.

Another object of the present invention is to perform the lining work of the liner 1 on the outer cover 2 with high efficiency and to improve the productivity.

Still another object of the present invention is that the wear resistance of the liner 1 itself can be arbitrarily improved, and the outer cover 2 is not deformed, thereby improving durability and manufacturing accuracy. It should be easy to plan.

[Means for solving problems]

Conventionally, it was considered that fluff cannot be prevented from coming out from the liner 1 unless the peripheral edge of the opening of the liner 1 facing the head window 4 of the outer cover 2 is strongly heat-welded with a considerably wide width. Therefore, the welding deformation on the outer cover 2 side is unavoidable. However, this not only causes the outer cover 2 to be deformed, but also promotes the occurrence of fluff when using a liner made of a certain kind of fiber, such as a non-woven liner containing the polyester fiber. I noticed that it also became. The present invention has been proposed from this point of view.

That is, the present invention is predicated on a disk cartridge in which the disk 3 is rotatably built in the outer cover 2 which is lined with the liner 1.

Here, the lining of the liner 1 with respect to the outer cover 2 includes a bonding method using an adhesive. However, most preferably, the outer cover 2 is made of a thermoplastic synthetic resin material, and the liner 1 is also a non-woven fabric made of a thermoplastic synthetic fiber,
The liner 1 is spot-heat-welded to the outer cover 2 as shown by the symbol P in FIGS. 1 and 3, or is partially heat-welded with another linear pattern or the like.

The disc cartridge shown in FIG. 2 has an outer cover 2
Was made of flexible vinyl chloride sheet,
The present invention is a disc cartridge in which a liner 1 is lined in a hard outer cover 2 and a disc 3 is mounted inside (a disc cartridge represented by so-called CFD or MFD).
Also target.

According to the present invention, in the disk cartridge having the above-mentioned basic structure, at least the peripheral portion of the opening of the liner 1 facing the head window 4 among the openings provided in the outer cover 2 is below the melting point of the nonwoven fabric liner 1 side. It is required that the outer cover 2 is compressed by a hot press method of heating and pressing at a temperature without leaving a heat welding mark on the outer cover 2 side. In FIG. 1, reference numeral 7 indicates the compression processing portion, and in the illustrated example, the portions indicated by the reference numerals P ₁ , P ₂ , P ₃ are the compression processing portion 7.

The compression processing portion 7 of the liner 1 does not need to be formed in an annular shape over the entire peripheral edge of the opening of the head window 4. Second
In the example of FIG. 3 and FIG. 3, the long side portions of the head window 4 in the shape of a long hole facing each other, in other words, the portion corresponding to the recording width of the disk 3 (the left and right long sides of the head window 4 in FIG. 2). It is sufficient that it is formed only in a certain area of (part).

The fiber bulk density of the compression processing part 7 in the liner 1 is 0.9.
As described above, it is desirable that there are few inter-fiber voids and they are in close contact with each other. The liner 1 is a non-woven fabric containing 50% by weight or more of polyester fiber in order to secure its own abrasion resistance, for example, 50% polyester fiber and 50% rayon fiber.
A non-woven fabric is preferably used.

Here, the fiber bulk density of the liner 1 is represented by the ratio Y / X of the specific gravities of the polymer material that is the fiber material forming the liner 1, where X is the specific gravity and Y is the apparent specific gravity of the liner 1. It also means the volume ratio of voids between fibers to the volume of the liner 1.

By the way, in the disk cartridge as shown in FIG.
Generally, as shown in FIG. 3, a liner 1 is attached to the outer cover 2.
The whole is partially lined by spot heat welding or the like, the compression processed portion 7 is formed at that time, and then both 1 and 2 are punched to form an opening such as a head window 4. Alternatively, the compression processing portion 7 is formed when the head window 4 is punched. However, in the case of a disk cartridge in which the outer cover 2 is a hard case body, the outer cover 2
The liner 1 having the opening corresponding to the head window 4 and the compression-processed portion 7 formed on the peripheral edge of the opening is positioned and lined on the head window 4 provided at.

However, with the liner 1 superposed on the outer cover 2, the compression processing part 7 is applied to the liner 1 by the hot press method.
When forming the, make sure that the outer cover 2 does not have welding marks. That is, the pressing force and the heating temperature are adjusted to instantaneously heat and press the liner 1 side. However, the form in which the compression processing portion 7 is heat-welded to the outer cover 2 shallowly is not positively excluded.

Of course, it is desirable to form the compression processing portion 7 also on the peripheral portion of the opening of the liner 1 which faces the central window 5 and the index hole 6, but this point is not particularly limited, and depending on the target disk cartridge. The compression processing part 7 is arbitrarily formed.

〔The invention's effect〕

According to the present invention as described above, at least the peripheral edge portion of the opening of the liner 1 facing the head window 4 is compressed with respect to the outer cover 2 so that the constituent fibers are in close contact with each other as compared with other portions. Then, it is cut to obtain an opening corresponding to the head window 4. Therefore, the shearing stress for cutting is accurately transmitted to each fiber, and the compression processing part 7
There is no displacement between the fibers at the cutting edge, and therefore the fibers do not fluff out from the cutting opening. Head wind 4
The cutting edge of the liner 1 facing the front is finished neatly and has no fuzz. In addition, the welding deformation around the head window 4 of the outer cover 2 unlike the conventional example does not occur, and it can be manufactured with high accuracy.

As a result, even when the embodiment in which the liner made of polyester fiber having excellent wear resistance and high shear strength is lined, dropout due to fiber fluff can be avoided,
A highly accurate disc cartridge with excellent durability can be obtained. In particular, in the case of a liner containing polyester fibers, even if fluff comes out during cutting, the fluff is not included in the outer cover 2 even if the fluff comes out during cutting. However, the fact that the head window 4 does not come out due to elastic restoration during cutting also helps prevent fuzzing.

〔Example〕

On the inner surface of the outer cover 2 made of a vinyl chloride sheet with a thickness of 200 μm, 50% polyester fiber with a specific gravity of 1.5 and a specific gravity of
A non-woven fabric liner 1 having a basis weight of 48 g / m ² and an apparent thickness of 270 μm (hence, the fiber bulk density is 0.7) mixed with 1.3% rayon fiber 50% was overlaid and placed on the outer cover 2 as indicated by symbol P in FIG. The whole non-woven liner 1 was partially spot-heat-welded. At that time, in the peripheral portion of the portion where the head window 4, the central window 5, and the index hole 6 should be opened, the corresponding portion of the non-woven liner 1 (P _1.
The portions indicated by P ₂ and P ₃ ) are heated at 250 ° C. from the liner side so that the thickness is 180 μm and the fiber bulk density is 0.92 to form the compression-processed portions 7 as shown in FIG. . The compression processed portion 7 is not heat-welded to the outer cover 2 due to the difference in melting point.

Next, the outer cover 2 was cut into a predetermined outer shape, and closing margins 8a, 8b, and 8c were formed around the three sides of the half part, and openings such as the head window 4, the central window 5, and the index hole 6 were punched out. .

Thus, the outer cover 2 lined with the non-woven fabric liner 1 is folded inward from the center through the folding curve L, and the opposing closing margins 8a and 8b are folded back and heat-welded to form a rectangular bag-shaped jacket A. By inserting the disk 3 from the insertion port and folding back the remaining closing margin 8c,
The magnetic disk cartridge shown in the figure was obtained.

[Brief description of drawings]

FIG. 1 is a sectional view taken along the line BB in FIG. 3, FIG. 2 is a plan view showing an example of a disk cartridge to which the present invention is directed, and FIG. 3 is a plan view showing its jacket in a developed state. 1 ... Liner, 2 ... Outer cover, 3 ... Disk, 4 ... Head window, 7 ... Compression processing part.

Claims (2)

[Claims] 1. A disc cartridge comprising a disc (3) rotatably contained in an outer gover (2) having a liner (1) lined therein, wherein the liner (1) contains 50% or more of polyester fiber. The outer cover (2) is made of non-woven fabric, the outer cover (2) is made of vinyl chloride or a copolymer sheet thereof, and at least the opening peripheral portion of the non-woven fabric liner (1) facing the head window (4) provided on the outer cover (2) is
The non-woven fabric liner (1) is compressed by a hot press method in which heat is applied from the non-woven fabric liner (1) side without leaving a heat-welding mark on the outer cover (2) side. A disk cartridge having a bulk density set to 0.9 or more. 2. The disk cartridge according to claim 1, wherein the liner (1) is made of a non-woven fabric in which 50% polyester fiber and 50% rayon fiber are mixed.