JPS61210576A - Flexible magnetic disc - Google Patents

Abstract

PURPOSE:To improve the positioning accuracy and rotation stability by provid ing a specific ring to a loading hole and a peripheral part. CONSTITUTION:The rings 4, 5 made of a hard material thicker than a disc 1 are provided respectively to the peripheral part and the outer circumferential part of the loading hole 2a of a flexible disc 1 provided with a magnetic layer 3. The positioning accuracy in loading the disc 1 is improved by the ring 4, the centrifugal force attended with rotation is increased by the ring 5 to improve the flatness of the disc 1, allowing to improve the rotating stability. Thus, the disc is rotated at high speed and the transmission density is increased.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a flexible magnetic disk formed by forming a magnetic layer on the surface of a flexible disk-shaped base material.

(Prior Art) A conventional flexible magnetic disk has a structure in which a magnetic layer is formed on the surface of a flexible, thin, disc-shaped base material made of molded resin by means such as coating.

(Problems to be Solved by the Invention) However, because conventional flexible magnetic disks are thin, they are easily affected by vibrations from other sources, and have poor rotational stability, resulting in Since the position easily fluctuates, there is a limit to the recording density, and since high-speed rotation cannot be performed, there is a problem that the transmission density is poor.

(Means for Solving the Problems) The flexible magnetic disk of the present invention is provided by providing a ring made of a hard material and thicker than the base material in the mounting hole and the outer circumference of the disk. By improving and reinforcing the positioning accuracy at the mounting hole, increasing the centrifugal force generated by rotation with the outer ring, and stretching the base material to improve one-rotation stability, recording density and transmission density are improved. This achieved an improvement in

(Embodiment) FIGS. 1 and 2 show an embodiment of a flexible magnetic disk according to the present invention, and the flexible magnetic disk 1 has a disk shape made of a flexible resin such as polyethylene terephthalate. A magnetic layer 3 is provided on one side of the base material 2 or on both sides as shown in the figure.
is applied directly or through a base material by a thin film forming technique such as vapor deposition or sputtering, and is applied from the base material 2 to the front and back sides of the periphery of the mounting hole 2a on the inner periphery of the disk 1 and the outer periphery. A ring 4.5 that is thick and made of hard molded resin or a metal plate is bonded with adhesive 6 as shown in the figure.
or heat welding or third
As shown in the figure, the ring 4' in the mounting hole 28 and the outer ring 5' are fixed by mechanical connection such as screws 7 and female threads 8 or fitting. Furthermore, as shown in FIG. 4, if the rings 4 and 5 are formed by resin molding, productivity is good and dynamic balance is also good.

With such a configuration, the outer rings 5, 5' act as weights, and the centrifugal force generated with rotation becomes large, and the base material 2 is pulled toward the outer circumference and is pulled toward the inner circumference. Rings 4 and 4' have a reinforcing effect, increasing the flatness of the surface.
Since the surface accuracy is improved and rotational stability is obtained, the relative positional accuracy between the head and the magnetic layer 3 is improved.
Since the distance between tracks can be reduced in consideration of the relative positional deviation between the head and the disk, recording density can be improved. Furthermore, since the moment of inertia of the disk is increased, rotational stability is improved and high-speed rotation is possible, so transmission density can be increased.

(Effects of the Invention) As described above, the flexible magnetic disk of the present invention is provided with a ring made of a harder material and thicker than the base material in the mounting hole and outer circumference of the disk. Therefore, the ring in the mounting hole plays the role of improving positioning accuracy, and the outer ring increases the flatness due to the increase in centrifugal force that accompanies rotation, and improves one-rotation stability. Since the relative positional accuracy between the head and the head is improved, the storage density is improved. Furthermore, according to the present invention, one rotation stability is improved by increasing the moment of inertia of the disk.

However, since high-speed rotation is possible, the transmission speed is improved.

Further, since the disk of the present invention has flexibility, it has the advantage that both a floating head and a contact head can be used.

[Brief explanation of drawings]

FIG. 1 is a plan view showing one embodiment of the flexible magnetic disk of the present invention, FIG. 2 is an enlarged cross-sectional view taken along line EE in FIG. 1, and FIGS. 3 and 4 are other embodiments of the present invention. It is a sectional view showing an example.

Claims (1)

[Claims] A flexible magnetic disk is formed by forming a magnetic layer on the surface of a disc-shaped base material made of a flexible resin, and the mounting hole and outer circumference of the disc are thicker than the base material. A flexible magnetic disk characterized by having a large ring made of a hard material.