JPS61115286A - Disc cartridge - Google Patents

Abstract

PURPOSE:To obtain a secure adhesion of the liner and external case, by making peripheral part of the unwoven fabric liner and adhesive pat of the external case radial and same size and adhering them by ultrasonic wave welding. CONSTITUTION:The welding pattern Q of a liner 3 and an external case 4 is so designed that welding is done almost radially towards the peripheral parts and many joining parts of same axis length form a joining part (b), and the density of joining part (b) of outside angle A of a notch 3b is higher than joining parts (b). When fusion welding or ultrasonic wave welding is applied, the deposition density of the outside corner A of the notch 3b is increased and becomes stronger than other joining parts (b), and further the deposition strength is also increased. Therefore the occurrence of peeling off of the liner 3 caused by the rotation of a disc 1 can be prevented. Since the axis length of each joining part is designed to be the same length, there is no protrusion of the liner 3 when the disc 1 rotates, failures such as deformation of the liner 3 due to the concentration of stress at and peeling off at the protrusive part are solved, and the causes to give an adverse effects to recording/reproducing the disc 1 are reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a disk cartridge rotatably containing a disk serving as an information medium.

[Conventional technology]

As shown in FIG. 3, a conventional disk cartridge includes a disk 1, a hub 2 fixed to the center of the disk 1, and a liner 3 made of nonwoven fabric that cleans the disk 1.

A head hole 5, which is disposed in an exterior case 4 made of hard synthetic resin, is provided in the exterior case 4 to enable contact between a head hole (not shown) and the disk 1.

Some devices have a structure in which a hub hole 6 or the like is formed to expose the hub 2 to the outside of the outer case 4.

The nonwoven fabric liner 3 in the disk cartridge is:
A central hole 3a and a notch 3b are formed so as not to contact the hub 2 and the head, and the liner 3 as a whole is approximately C-shaped. was bonded to the exterior case 4 by heat welding or ultrasonic welding. The welding pattern P is formed so that the joint parts a of the joints between the exterior case 4 and the liner 3 have their axes parallel to each other, are tilted in a certain direction, and have equal gaps. be.

The shape of the welding pattern P described above is 2 exclusively i! Il! This welding pattern P was determined from the viewpoint of ease of production.
-, there were parts on the circumferential side of the liner 3 where the lengths of the joints a were partially different. However, when a bonding method using ultrasonic welding is adopted, the characteristics of ultrasonic welding are that if the bonding area a is short, energy will be concentrated;
When the is long, the energy tends to diffuse, as a concrete phenomenon.

The degree of welding is smaller when the joint portion a is longer than when the joint portion a is short. Therefore, the deformation of the joint part a varies depending on the part, and in some places the outer case 4 bulges inward, and on the other hand, there are places where the adhesive strength between the liner 3 and the outer case 4 is insufficient. As a result, when the disk 1 rotates, the liner 3 is deformed in the raised portion due to contact with the disk 1, and the liner 3 is lifted up or rolled up from areas where the adhesive strength is insufficient, as shown in FIG. These causes fluctuations in the rotational torque of the disk 1, and also cause the liner 3 to flutter due to its contact with the disk l, causing fibers to be pulled out and attached to the surface of the disk l, adversely affecting recording and playback. was.

[Problem that the invention seeks to solve]

The present invention solves the problems of the prior art described above, namely, when using ultrasonic welding to bond the liner and the exterior case, fluctuations in the rotational torque of the disk resulting from uneven adhesion between the liner and the exterior case, or The purpose of the present invention is to provide a disk cartridge in which the liner is firmly and reliably adhered to the outer case while preventing the occurrence of recording/reproducing defects caused by damage to the liner.

[Means for solving problems]

In order to solve the above-mentioned problems, one aspect of the present invention is to bond the nonwoven fabric liner and the exterior case by ultrasonically welding the joint portion between the circumferential side of the nonwoven fabric liner and the exterior case in a radial and equal length manner. be.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 1 and 2. Incidentally, members having the same functions as those explained in FIGS. 3 and 4 are given the same reference numerals.

That is, the outer case 4 made of hard synthetic resin has a hub hole 6 in the center, and a rectangular head hole 5 below the center.
It is formed. This exterior case 4 is formed by joining a pair of cases, an upper case 4a and a lower case 4b, as is well known, and has a disk 1 inside and a disk 1 inside.
Rayon, which performs a cleaning action by contacting the top and bottom surfaces of
A pair of liners 3 made of a nonwoven fabric of thermoplastic synthetic resin fibers such as polypropylene or polyester are interposed between the upper case AaC (lower case 4b) and the liner 3, and the liner 3 is connected to the upper case 4a (lower case 4b). The pressing member 7 slightly bulges out from the inner surface of the hub hole 6, and the end surface thereof is exposed to the outside of the outer case 4 from the hub hole 6.

Katsu Disc 1! A fixed hub 2 is arranged in the center.

As is well known, the nonwoven fabric liner 3 has an arc-shaped shape at a position facing the hub hole 6 and the head hole 5, respectively, in order to prevent contact between the hub 2 and the head (not shown) and the liner 3. a central hole 3a forming a shape, and a notch 3b forming a rectangular shape.
It has a substantially C-shape with a pair of ears 3c formed on the sides.

In this embodiment, the welding pattern Q between the liner 3 and the exterior case 4 is as shown in the first pattern.

The liner 3 is formed with a number of joint portions that are approximately radial and have equal length axes on the circumferential side thereof.

In particular, the density of the joint at the joint at the outer corner A of the notch 3b is higher than that at the other joints. Also, the side B of the liner 3 of the notch 3b
If the radial direction of the joint part is the same as the radial direction of the joint part at the circumferential part of the liner 3, the joint part cannot be formed on this side 115B. It's Nishide. However, the axial length of each joint part in the side part B is the same as the length of each joint part in one circumferential part.

Therefore, when heat welding or ultrasonic welding is performed using the welding pattern Q, the welding density at the outer corner A of the notch 3b increases, and the adhesive strength increases compared to other joint parts, and furthermore, compared to the conventional disk cartridge. Since the adhesive strength is increased compared to the liner 3, it is possible to prevent the liner 3 from turning over when the disk 1 rotates.

In addition, especially when ultrasonic welding is employed as a welding method, the joining portion in the welding pattern Q is $+! 1
The ultrasonic wave spreads because m lengths are made equal lengths.

The degree of concentration can be made the same in each joint part, the state of the joint part, that is, the welding state and the deformation state, is uniform, there is no bump in the joint state in some parts, and there is no abnormal protrusion of the liner 3. does not occur.

Since the axial lengths of the joint parts are made equal in this way, the liner 3 does not protrude from the rotating part of the disk 1 as in the conventional case, and therefore, concentrated stress is applied to the protruding part, causing the liner 3 to Problems such as deformation and rolling up can be resolved.

As mentioned above, by adopting the welding pattern Q of this embodiment, deformation and curling of the liner 3 due to the rotation of the disk will not occur, so the rotational torque of the disk 1 will be constant, and the deformation of the liner 3 will not occur. In addition, the fibers of the liner 3 that have been caused by curling are no longer pulled out, and the causes of adverse effects on recording and reproduction of the disc 1 can be reduced.

The gist of the present invention resides in that the joint portion between the circumferential side portion of the nonwoven fabric liner 3 and the exterior case 4 is made substantially radial so that the length of the joint portion is equal.
There is no need to increase the density of the joint portion of the outer peripheral corner portion A of b.

〔Effect of the invention〕

As explained above, 1. Even if the nonwoven fabric liner and the exterior case are bonded by ultrasonic welding, the degree of adhesion at each bonding location, that is, the deformation, and the bonding strength can be made uniform, and the deformation of the nonwoven fabric liner and the N1tL can be made uniform. It is possible to prevent the occurrence of such problems, the rotational torque of the disk becomes constant, and the negative influence of the liner on the disk can be reduced.

It is possible to provide a disk cartridge that can perform good recording and playback.

[Brief explanation of drawings]

FIG. 1 is a plan view showing the inside of a disk cartridge according to the present invention, FIG. 2 is a side sectional view thereof, FIG. 3 is a plan view showing the inside of a conventional disk cartridge, and FIG. 4 is a deformation of the liner. It is an explanatory diagram showing a state. 1...Disk, 2...Hub, 3...
...Nonwoven fabric liner, 4...Exterior case, Q.
...Welding pattern, b...Joint location. Figure 7 Figure 2

Claims (1)

[Claims] In a disk cartridge comprising an outer case made of synthetic resin, a disk, a hub fixed to the center of the disk, and a nonwoven fabric liner that cleans the surface of the disk, the peripheral side of the nonwoven liner and the outer case are provided. What is claimed is: 1. A disk cartridge characterized in that a nonwoven fabric liner and an exterior case are bonded together by ultrasonic welding with the joining portions substantially radial and of equal length.