JPS63146284A - Disk cartridge - Google Patents

Abstract

PURPOSE:To improve the anti-medium characteristics as well as the welding accuracy with a disk cartridge by using the thermoplastic synthetic resin to a cartridge case and a nonwoven fabric containing both acrylic fiber and hot- melt fiber layers to a cleaning sheet respectively and attaching the nonwoven fabric to the inner surface of the cartridge case. CONSTITUTION:A cartridge case 1 is made of an oblong case sheet material 4 of hard polyvinyl chloride, for example, and contains three bonding edge parts 5a, 5b and 5c at an end part of the case 1. While an oblong cleaning sheet material 6 having an approximately same size as the material 4 is fixed by welding onto one side of the material 4. The sheet 6 uses a nonwoven fabric containing an acrylic fiber layer 3a and a hot-melt fabric layer 3b and is attached to the inner surface of the case 1 with the layer 3b set opposite to the side of the case 1. Thus it is possible to obtain a cartridge containing a cleaning sheet which is excellent in the ant-medium characteristics and the fixing properties to a cartridge case.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a disk cartridge such as a magnetic disk cartridge, which uses a flexible cartridge case or a cartridge case made of hard synthetic wood, and is used for cleaning. It concerns the seat.

[Conventional technology]

A magnetic disk cartridge includes a cartridge case having a magnetic head insertion slot and a rotation drive hole, a flexible magnetic disk rotatably housed within the cartridge case, and a cleaning sheet supported on the inner surface of the cartridge case. It is mainly composed of.

[Problem that the invention seeks to solve]

By the way, conventional cleaning sheets for magnetic disk cartridges are made of nonwoven fabrics such as mixed fibers of rayon and polypropylene, mixed fibers of rayon and polyethylene terephthalate, or polyethylene terephthalate fibers. It was fixed to the inner surface of the cartridge case with adhesive.

However, cleaning sheets made of fibers as described above do not have good cleaning properties for magnetic disks, and may cause scratches on the surface due to sliding contact with the magnetic disk, or may cause fibers to be removed from the cleaning sheet due to sliding contact with the magnetic disk. There are problems such as the fibers falling off and adhering to the magnetic disk or magnetic head, adversely affecting the recording and reproducing characteristics.

The purpose of the present invention is to solve the drawbacks of such prior art,
To provide a disk cartridge which has a cleaning sheet with excellent media-resistance properties and which has high welding accuracy between the cartridge case and the cleaning sheet.

[Means for solving problems]

In order to achieve the above-mentioned object, the present invention comprises: (1) a cartridge case made of, for example, a flexible sheet material or a molded body of hard synthetic resin; a flexible disk rotatably housed within the cartridge case; The object of the present invention is a disk cartridge including a cleaning sheet thermally welded and supported on the inner surface of the cartridge case.

In the present invention, the cartridge case is made of thermoplastic synthetic resin, and the cleaning sheet is made of two layers of nonwoven fabric, an acrylic fiber layer and a heat-melt fiber layer, and the heat-melt fiber layer is placed on the side of the cartridge case. The cartridge case is characterized in that a cleaning sheet is welded and supported on the inner surface of the cartridge case so as to face each other.

[Embodiments of the invention]

Specific media properties of the cleaning sheet include, for example, cleaning properties against disks such as magnetic disks, scratch resistance against the disk, and degree of deterioration of fibers of the cleaning sheet due to sliding contact with the disk. As a result of various studies on nonwoven fabrics that have excellent media resistance properties, they found that nonwoven fabrics mainly composed of acrylic II fibers are a good enemy.

However, even this non-woven fabric mainly composed of acrylic fibers is not without some problems.

If you try to weld this nonwoven fabric mainly made of acrylic fibers to the inner surface of the cartridge case using a method that takes a relatively long heating time, such as a normal heat press, the fibers will shrink and melt due to the characteristics of acrylic fibers. As a result, the welding strength of the cleaning sheet to the cartridge case is insufficient, and repeated sliding contact between the disks may cause the cleaning sheet to separate from the cartridge case. In addition, hard lumps are formed on the surface of the cleaning sheet, which deteriorates the cleaning performance of the disk and causes severe scratches on the disk, thereby eliminating the above-mentioned characteristics of acrylic fibers.

In consideration of this point, the present invention solves the above-mentioned problems by making the cleaning sheet from a 2M nonwoven fabric consisting of acrylic fibers and a heat-melting fiber layer, and by welding the heat-melting fiber layer to the inner surface of the cartridge case. It is something.

Examples of thermoplastic synthetic resins used in the cartridge case include polyvinyl chloride, ABS resin, polyacetal resin, polystyrene resin, etc.
A desired cartridge case is formed by making it into a jacket shape or by injection molding as described below.

The above-mentioned magnetic disk is made of a base film made of polyester or polyimide, and a magnetic thin film is formed on one or both sides of the base film by an appropriate method such as coating, vapor deposition, or sputtering, and has appropriate flexibility. There is.

The structure of the cleaning sheet fixedly supported on the inner surface of the cartridge case will be explained in detail using the first specific example.

Figures 1 to 4! ! FIG. 1 is a diagram for explaining a magnetic disk cartridge according to a first embodiment of the present invention.

Figure 1 is a bottom view of the magnetic disk cartridge, Figure 2 is an exploded view of the cartridge case and cleaning sheet of the magnetic disk cartridge, Figure 3 is an enlarged sectional view of the cleaning sheet, and Figure 4 is the cleaning sheet attached to the cartridge case. FIG.

The magnetic disk cartridge is composed of a cartridge case 1, a sheet-like flexible magnetic disk 2 rotatably housed within the cartridge case 1, and a cleaning sheet 3 fixed to the inner surface of the cartridge case 1. There is.

As shown in FIG. 2, the cartridge case 1 is made of a rectangular case sheet material 4 made of, for example, hard polyvinyl chloride, and has three bonding edges 5a, 5 at one end.
b, 5e are provided.

A rectangular cleaning sheet material 6 having approximately the same width is fixed to one side of the case sheet material 4 by welding.

The two square parts 4a, 4b and 6a, 6b of the case sheet material 4 and the cleaning sheet material 6 divided by the center folding line X (imaginary m) have the center hole 7 of the magnetic disk 2 (see FIG. 1). Center hole with a larger diameter than 7
A rotation drive hole 8 for exposing the peripheral part of the magnetic head insertion hole 9. Circumferential position of magnetic disk 2! A detection hole 10 for detecting In and correct tracking, a notch 11 for detecting whether side A or B of the magnetic disk cartridge, etc. are formed at symmetrical positions.

As shown in the figure, after placing the cleaning sheet material 6 on the case sheet material 4, welding 12 in spots over almost the entire surface of the cleaning sheet material 6,
Said rotation drive hole 8. Magnetic head insertion port 9. Detection hole 10
and linear welding 13 around the notch 11 K
Therefore, the cleaning sheet material 6 is fixed to the case sheet material 4 without losing its flexibility and elasticity. In this case, the cleaning sheet material 6 does not necessarily need to be welded 12 in spots over the entire surface, but it is only necessary that the cleaning sheet material 6 is fixed to the extent that it does not easily separate from the case sheet material 4.

After that, fold the cleaning sheet material 6 in half from the center fold 1slX described above with the cleaning sheet material 6 on the inside, and fold it into the square part 4.
Of the bonding edges 5a, 5b, 5e provided on the side b, the bonding edges 5a, 5c facing each other are folded over the outside of the other square portion 4a, and the first By partially welding 14 as shown in the figure, a bag-like body with one side open is created.

A magnetic disk 2 punched from a sheet-like raw material is inserted into this bag-like body, and then the remaining bonding edge 5b is folded over the outside of the square portion 4a and welded 14, thereby forming a magnetic disk cartridge. Finish assembly.

As shown in FIG. 3, the cleaning sheet 3 is composed of two layers: the side facing the magnetic disk 2 is an acrylic fiber layer 3a, and the side facing the cartridge case 1 is a heat-melting fiber layer 3bT.

Acrylic fiber is a synthetic fiber containing about 85% or more acrylonitrile, and is copolymerized with acrylic ester, vinyl acetate, styrene sulfonic acid, etc. to improve friction strength and dyeability.

Acrylic fibers are most similar to wool among synthetic fibers, and have excellent flexibility and soft touch. The tensile strength of acrylic fiber (stable) is approximately 2.5 to 5.0 g.
/D, the elongation rate is about 25-50%, the elongation modulus (at 3% elongation) is about 90-95%, the specific gravity is about 1.14-1.17, and the fineness is about 1-6 denier. be done.

The heat-melting fiber layer 3b is made of polyester, for example.

It is composed of heat-meltable fibers such as polyamide, polyvinyl chloride, ethylene-vinyl acetate copolymer, and vinyl chloride-vinyl acetate copolymer.

Hot melt am fiber layer b 171K sa Lt 0.02m
+s more than teTo! If it is thinner than this, heat weldability will be poor.

In addition, if the thickness is less than twice that of the acrylic fiber layer 3a, the cushioning properties of the cleaning sheet as a whole will be good.
And the mass of fibers melted during welding forms the acrylic fiber layer 3a.
The cleaning properties of the acrylic fiber layer 6a can be maximized without coming out on the surface and damaging the disc.

It is possible to prevent occurrences such as dropouts.

For example, by passing this cleaning sheet material 6 between rollers with knurling on the curved surface (emboss processing), the cleaning sheet material 6 is formed as shown in FIG.
A large number of depressions and depressions 23 are formed on the surface. Note that in FIG. 2, the unevenness 23 is omitted to simplify the drawing. The cleaning sheet material 6 constructed in this manner is welded in spots 12 and linearly welded 13 to the case sheet material 4 as described above.

The following specific example will be described.

(Example) Cotton made of 1.5 denier acrylic fibers alone was blown with water or air to intertwine, and then 1.5 denier polyester fiber was interlaced in the same manner. After that, these were passed through a hot roll and heat treated, so that the acrylic fiber layer was 0.15 mm and the polyester fiber layer was 0.15 mm.
．． 05+wm, basis weight 35g/rd, thickness 0.2
Make 0mm cleaning sheet material.

This cleaning sheet material was made into a case sheet material made of a polyvinyl chloride sheet with a thickness of 0.25-1.

200°C with the polyester fiber layers facing each other.
After heat welding and opening a predetermined portion, bending and fusing were performed to manufacture a cartridge case.

(Comparative Example 1) In the example, the weight per tsubo is 35 g/bo and the thickness is 0.02 m.
A cartridge case was manufactured in the same manner as in the previous example using a cleaning sheet material made of acrylic fibers of m.

(Comparative Example 2) Basis weight is 35g/rrf, thickness is 0.02mm, 1.5
80% denier rayon fiber and 22% polypropylene fiber
Using a mixed cleaning sheet material consisting of 0%
A cartridge case was manufactured in the same manner as in the previous example.

The adhesion between the cartridge case and the cleaning sheet, the presence or absence of protruding fibers at the opening, and the presence or absence of running scratches on the magnetic disk were investigated for these cartridge cases and summarized in the following table.

The weldability is determined by welding cleaning sheet materials in spots on the case sheet material at intervals of 711I11 for each of the samples.

Peel off part of this cleaning sheet material in a strip shape of about 1cm wide, leaving the other end firmly attached to the case sheet material.Next, put the case sheet material up and the cleaning sheet material down. By doing so, the part peeled off from the case sheet material hangs down from the case sheet material, and a weight is applied to the hanging part to apply a load in the direction that the cleaning sheet material peels from the case sheet material, and the amount of the load is gradually reduced. The load (g) was measured when the fixed part of the cleaning sheet material (#11 fixed part) started to peel off from the case sheet material.

To check whether there are any fibers protruding from the opening or whether there are running scratches on the magnetic disk, enclose a magnetic disk in the cartridge case of each sample, attach it to a recording/playback device, and continuously hit it for 24 hours without head contact. The presence or absence of protruding fibers and running scratches were examined.

As is clear from the test results, it can be seen that the welding properties, cutting properties, and abrasion resistance of magnetic disks of the embodiments of the present invention are superior to those of the comparative examples.

5 to 9 are for explaining a magnetic disk cartridge according to a second embodiment of the present invention, FIG. 5 is an exploded perspective view of the disk cartridge, and FIG. 6 is a cleaning sheet attached to the upper case. FIG. 7 is a plan view showing the state in which the cleaning sheet is adhered to the lower case, and FIG. 8 is an enlarged cross-sectional view of the vicinity of the magnetic head insertion port showing the state in which this magnetic disk cartridge is used. , FIG. 9 is an enlarged sectional view of the vicinity of the elastic piece of this magnetic disk cartridge.

The magnetic disk cartridge is stored in the cartridge case 26.
, a magnetic disk 27 rotatably housed therein, and a shutter 28 slidably supported by a cartridge case 26 .

The cartridge case 26 includes an upper case 26a and a lower case 2.
6b, which are molded from hard synthetic resin such as ABS resin.

An opening 29 for inserting a rotational drive shaft is formed approximately in the center of the lower case 26b, and a rectangular head insertion opening 3 is formed near the opening 29.
Similarly, a head insertion port 30 is provided in the upper case 26a. Near the front surfaces of the upper case 26a and the lower case 26b, as shown in FIG. The magnetic head insertion port 30 is opened in the.

As shown in FIG. 6, counterbore-shaped recesses 42 and 42 are formed on the inner surface of the upper case 26a and on both left and right sides of the magnetic head insertion opening 30, respectively.

The vertical width W1 of the recess 42 is approximately equal to the cap (vertical width) W2 in the longitudinal direction of the magnetic head insertion port 30, and the horizontal width W of the recess 42 is
3 is regulated to be at least 0.3 times the cap (width) W4 in the direction orthogonal to the longitudinal direction of the magnetic head insertion port 30, preferably in the range of 0.5 to 1.5 times.

On the upstream side of the magnetic head insertion port 30 in the disk rotation direction in the upper case 26a, there are a large number of linearly extending protrusions 4.
3 are provided, of which two on both sides are protrusions 43 on the inside.
It's slightly higher than that.

An arc-shaped regulating rib 44 for regulating the storage position of the magnetic disk 27 is protruded from the inner surface of the upper case 26a, and a part of the regulating rib 44 passes through the end of the recess 42.
It also serves as a reinforcement for the surrounding area.

As shown in FIG. 6, a substantially C-shaped cleaning sheet 45 having the same structure as in the previous embodiment is inserted inside the regulating rib 44. An opening 46 provided at a position corresponding to the magnetic head insertion opening 30 of the cleaning sheet 45
The width @W5 is designed to be slightly larger than the width W4 of the magnetic head insertion port 30. By placing the cleaning sheet 45 on the inner surface of the upper case 26a, the recesses 42 and protrusions 43 are also covered, and the cleaning sheet 4
5 is welded to the upper case 26a.

As described above, since the recess 42 of the upper case 26a has a sufficient width, the opening 46 of the cleaning sheet 45 is wide enough as shown in FIG. The a-edge can be welded 47 within the recess 42 .

As shown in FIG. 7, a protruding support portion 48 and a protruding protrusion 49 for preventing sticking are provided on the inner surface of the lower case 26m at a position substantially facing the protrusion 43 of the upper case 26a.

As shown in FIGS. 7 and 9, the base portion 51 of the elastic piece 50 formed by bending a plastic sheet is attached to the inner surface of the lower case 26b and near the support portion 48 by appropriate means such as adhesive or heat fusion. The free end 52 of the fixed zero elastic piece 50 is supported by the support portion 48 to maintain its inclined state.

A regulating rib 44 is also protruded from the inner surface of the lower case 26b, and a cleaning sheet 45 is disposed inside the regulating rib 44. The width W5 of the opening 46 provided in the cleaning sheet 45 at a position corresponding to the magnetic head insertion opening 30 is designed to be slightly larger than the width W4 of the magnetic head insertion opening 30. By placing the cleaning sheet 45 inside the lower case 26b as shown in FIG.
0 is covered, and the peripheral portion of the cleaning sheet 45 is welded 47 to the lower case 26b, but the welding 47 is omitted near the 1 elastic piece 50.

When a magnetic disk cartridge is assembled by combining the upper case 26a and the lower case 26b.

As shown in FIG. 9, the lower case 26b is
The cleaning sheet 45 is partially lifted up, and the lifting is pushed down by the protrusion 43 provided on the upper case 26a, so that the magnetic disk 27
is elastically held between the upper and lower cleaning sheets 45 and 45.

As the magnetic disk 27 rotates, the cleaning sheet 45 cleans the surface of the disk.

FIG. 8 is a diagram showing how the magnetic disk cartridge is used, and numeral 53 in FIG. 1 is a magnetic head.

In this example as well, as in the case where the case sheet material made of hard vinyl chloride is used, the welding properties are lower than those using the cleaning sheet material made of other materials.
It has been confirmed that the cutting performance, cleaning performance, and scratch resistance of magnetic disks are all excellent.

〔Effect of the invention〕

In the present invention, as described above, the media layer facing the disk in the cleaning sheet is composed of an acrylic fiber layer. This acrylic fiber has excellent flexibility among synthetic fibers, does not damage the surface of the disk that rotates once, does not become fluffy, and has a high cleaning effect. In addition, since the fibers have good force-tightening properties, when a disk cartridge is manufactured by cutting, a portion of the fibers does not protrude inward from, for example, the periphery of the head insertion opening or rotational drive hole.

In particular, if fibers protrude toward the head insertion port, errors may occur during recording or reproduction. As mentioned above, acrylic fibers have excellent cutting properties, so there are no errors caused by fibers sticking out.

Also, the cleaning sheet is fixed to the inner surface of the cartridge case using heat-melting fibers.

The welding strength of the cleaning sheet is high, so there is no need to worry about the cleaning sheet peeling off from the cartridge case.

As described above, it is possible to provide a disk cartridge having a cleaning sheet with excellent properties such as anti-media properties and adhesion properties to a cartridge case.

[BRIEF DESCRIPTION OF THE DRAWINGS] FIGS. 1 and 4 are for explaining a magnetic disk cartridge according to a first embodiment of the present invention. FIG. 1 is a bottom view of the magnetic disk cartridge, and FIG. 2 is a bottom view of the magnetic disk cartridge. FIG. 3 is an enlarged sectional view of the cleaning sheet, FIG. 4 is a plan view of the cleaning sheet before it is attached to the cartridge case, and FIG. 5 is a developed view of the cartridge case and cleaning sheet of the magnetic disk cartridge. An exploded perspective view of a magnetic disk cartridge according to a second embodiment of the invention, FIG. 6 is a bottom view of the upper case of the magnetic disk cartridge with a cleaning sheet attached, and FIG. 7 [2I is an exploded perspective view of the magnetic disk cartridge with a cleaning sheet attached. 8 is a plan view of the lower case, and FIG. 8 is an enlarged sectional view of the vicinity of the magnetic head insertion port showing the usage state of this magnetic disk cartridge. FIG. 9 is an enlarged sectional view of the vicinity of the elastic piece of this magnetic disk cartridge. 1... Cartridge case, 2... Magnetic disk, 3... Cleaning sheet, 3a
... Acrylic fiber layer, 3b ... Heat-melting fiber layer, ... 1, 2 ... Spot welding, 1
3... Linear welding, 26... Cartridge case, 26a... Upper case, 26b...
... lower case, 27 ... magnetic disk, 45
...Cleaning sheet, 47...Welding. Figure 1 ~ 0, Vz Figure 6 Figure 7

Claims (1)

[Claims] (1) A disk cartridge comprising a cartridge case, a disk rotatably housed within the cartridge case, and a cleaning sheet welded and supported on the inner surface of the cartridge case, wherein the cartridge case is made of thermoplastic synthetic resin. The cleaning sheet is composed of two layers of nonwoven fabric, an acrylic fiber layer and a heat-melt fiber layer, and the heat-melt fiber layer is in contact with the cartridge case side, and the cleaning sheet is welded and supported on the inner surface of the cartridge case. A disc cartridge featuring: