JPH0519232B2 - - Google Patents

Description

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

[Conventional technology]

In the case of conventional disk cartridges, the third
As shown in the figure, disk 1 and this disk 1
A hub 2 fixed to the center of the disc 1 and a liner 3 made of non-woven fabric that performs a cleaning action on the disc 1 are arranged in an exterior case 4 made of hard synthetic resin,
A head hole 5 is provided in the outer case 4 to enable contact between a head (not shown) and the disk 1.
There is also a structure in which a hub hole 6 is formed to expose the hub 2 to the outside of the outer case 4.

The nonwoven fabric liner 3 in the disk cartridge has a central hole 3a and a notch 3b so as not to come into contact with the hub 2 and the head, and the liner 3 as a whole is approximately C-shaped. In pattern P, the peripheral side of the liner 3 was bonded to the outer case 4 by thermal 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 was determined solely from the viewpoint of ease of mold production, but in this welding pattern P, there are parts on the circumferential side of the liner 3 where the length of the joint part a is different. Was. However, when a bonding method using ultrasonic welding is adopted, as a characteristic of ultrasonic welding, energy tends to be concentrated if the bonded part a is short, and energy tends to be diffused if the bonded part a is long. teeth,
The degree of welding is smaller when the joint portion a is longer than when the joint portion a is short. Therefore, the joint part a
The deformation of the liner differed from part to part, and in some places the outer case 4 was bulged inward, and on the other hand, there were places where the adhesive strength between the liner 3 and the outer case 4 was insufficient. As a result, when the disk 1 rotates, the liner 3 at the raised portion due to contact with the disk 1
As shown in Fig. 4, the liner 3 may float or roll up due to the deformation of the liner and the places where the adhesive strength is insufficient, which causes fluctuations in the rotational torque of the disk 1, and The liner 3 flutters due to friction with the disk 1, and fibers are pulled out and adhere to the surface of the disk 1, causing an adverse effect on recording and reproduction.

[Problem that the invention seeks to solve]

The present invention solves the above-mentioned problems of the prior art, 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 To provide a disk cartridge in which a liner is firmly and reliably adhered to an outer case, and prevents recording/reproducing failures caused by damage to the liner.

[Means for solving problems]

In order to solve the above-mentioned problems, the present invention provides a disk in which an outer case made of synthetic resin is provided with a disk, a hub fixed to the center of the disk, and a nonwoven fabric liner that cleans the surface of the disk. In the cartridge, the joining portions of the outer circumferential side and the inner circumferential side of the nonwoven fabric liner and the outer case were formed into substantially radial lines of equal length and ultrasonically welded to join the nonwoven fabric liner and the outer case.

〔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 is made of hard synthetic resin.
A hub hole 6 is formed in the center, and a rectangular head hole 5 is formed below the center. As is well known, this exterior case 4 includes an upper case 4a and a lower case 4b.
It is made up of a pair of cases joined together, and has a disk 1 inside, and is made of a nonwoven fabric made of thermoplastic synthetic resin fibers such as rayon, polypropylene, or polyester, which comes in contact with the top and bottom surfaces of the disk 1 to perform a cleaning action. A pair of liners 3 are interposed between the upper case 4a (lower case 4b) and the liner 3, and the liner 3 is connected to the upper case 4a (lower case 4b).
b) an extrusion member 7 slightly protruding from the inner surface, and an end surface exposed to the outside of the outer case 4 from the hub hole 6;
A hub 2 fixed to the center of the disk 1 is also disposed.

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

In this embodiment, the welding pattern Q between the liner 3 and the outer case 4 is as shown in FIG.
The liner 3 is made up of a number of joint parts b that are substantially radial and have equal length axes on the circumferential side of the liner 3, and the density of the joint part b at the joint part of the outer corner A of the notch part 3b is particularly high. , is formed to be higher than the joint portion b of the other joint locations. Further, if the joint part b of the side part B of the liner 3 of the notch 3b is made the same as the radial direction of the joint part b in the circumferential part of the liner 3, the joint part cannot be formed at this side part B, so the circumference The radial direction is different from the radial direction of the joint portion in the section. However, the side part B
The axial length of each joint portion b in the circumferential portion is the same as the length of each joint portion b in the circumferential portion.

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 the other joint parts b, which further improves the bonding strength compared to the conventional welding pattern Q. Since the adhesive strength is increased compared to the liner 3 of the disk cartridge, it is possible to prevent the liner 3 from turning over when the disk 1 is rotated.

In addition, when ultrasonic welding is employed as a welding method, the axial lengths of joint parts b in the welding pattern Q are made equal, so that the degree of diffusion and concentration of ultrasonic waves is the same in each joint part. Therefore, the state of the joint portion, that is, the welded state and the deformed state, becomes uniform, the joint state does not partially bulge, and the liner 3 does not protrude abnormally.

Since the axial lengths of the joint parts b are made equal in this way, the liner 3 does not protrude into 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 You can eliminate problems caused by deformation or rolling up.

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, and therefore the rotational torque of the disk 1 will be constant, and the liner 3 will be The fibers of the liner 3 that have been caused by deformation or curling are no longer pulled out, and the causes of adverse effects on recording and reproduction of the disk 1 can be reduced.

The gist of the present invention resides in that the joint portion between the peripheral 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 part b of the outer peripheral corner part A.

[Effects of the Invention] As explained above, the present invention makes it possible to equalize the degree of adhesion, that is, the deformation and adhesive strength at each bonding point, even if the nonwoven fabric liner and the exterior case are bonded together by ultrasonic welding, and the nonwoven fabric To provide a disk cartridge which can prevent deformation and curling of the liner, keep the rotating torque of the disk constant, reduce the bad influence of the liner on the disk, and achieve good recording and reproduction.

[Brief explanation of the drawing]

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 liner It is an explanatory view showing a deformed state. 1...Disc, 2...Hub, 3...Nonwoven fabric liner, 4...Exterior case, Q...Welding pattern,
b... Joint location.

Claims (1)

[Claims] 1. A disk cartridge comprising a synthetic resin outer case, a disk, a hub fixed to the center of the disk, and a nonwoven fabric liner that cleans the surface of the disk, wherein the outer peripheral side of the nonwoven fabric liner and 1. A disk cartridge characterized in that the nonwoven fabric liner and the outer case are joined by ultrasonic welding to form a substantially radial and equal-length line at a joining portion between the inner circumferential side and the outer case.