JPH0411950B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an improvement of a jacket for a flexible disk for magnetic recording, particularly for a flexible disk for perpendicular magnetic recording.

(Prior art and its problems) Flexible disk drivers for magnetic recording are provided with pads to hold down the jacket and improve contact between the magnetic recording medium (hereinafter simply referred to as the medium) and the head. At the part where the pad contacts the jacket, there is a strong contact between the liner provided on the jacket and the medium on the inside of the jacket. Compared to conventional magnetic recording media, perpendicular magnetic recording media have a disadvantage in that the metal surface of the magnetic material is exposed on the surface, so scratches caused by pad pressure appear more prominently, which adversely affects magnetic recording and reproduction.

To explain this with reference to the drawings, FIG. 4 is a sectional view of the flexible disk 3 housed in the driver, showing the positional relationship between the pad 1, the jacket 2, etc. 5 is a liner that covers the inside of the jacket 2, 10 is a pad holder fixed inside the driver, and 4 is a driver collector.
FIG. 5 shows, in a plan view, the portion in which the pad 1 comes into contact. FIG. 6 shows that the pad 1 is in contact with the jacket 2, and the jacket 2 is in contact with the pad receiver 10.
FIG. 3 is an enlarged cross-sectional view of the portion when the flexible disk 3 is sandwiched between the flexible disk 3 and the flexible disk 3. FIG. However, deformation (curving) of the jacket 2 and liner 5
is exaggerated. The liner 5 strongly contacts the flexible disk 3 at the location where the pad 1 is in contact with it, causing damage to the media and uneven rotation.

Conventionally, the material of the liner 5 is PET (polyethylene terephthalate) or 25% to 50% of this.
The material mixed with PP (polypropylene) is used, so the coefficient of friction is not low and the lubricity is poor.

(Object of the Invention) An object of the present invention is to solve these conventional disadvantages and to provide a new jacket that can be used in a flexible disk for perpendicular magnetic recording without causing any damage to the disk.

(Structure of the Invention) The present invention provides a liner made of a material with a low coefficient of friction and/or high lubricity at a portion of the inside of the jacket that contacts the disk at the location where the jacket holding pad of the floppy disk driver comes into contact. The above objective has been achieved.

(Embodiment) FIGS. 1 and 2 are an enlarged cross-sectional view of a pad abutting part and a developed view of a jacket 2 according to an embodiment of the present invention, in which 20 is a norishiro, 6 is a low friction coefficient and /Or a highly lubricating liner with liner 5 on the inside of the jacket in the area where pad 1 comes into contact, which is slightly wider than the area where pad 1 comes into contact.
Alternatively, it may be provided on the liner 5.
By providing the liner 6 here, even if pressure is applied by the pad 1, the coefficient of friction between the sheet 6 and the medium 3 is small, so damage to the medium 3 and occurrence of uneven rotation can be avoided. FIG. 3 shows another embodiment of the installation of the liner 6. In addition, although the liner 6 was made to coexist with the liner 5 in the embodiment, it may be advantageous to use the liner 6 as the entire liner because it reduces the number of manufacturing steps. Examples of the material of the liner 6 include a Teflon resin thin film,
Examples include adhesion of a carbon-based material layer. The material thickness of the liner 6 is selected to be an appropriate value in consideration of peeling and abrasion of the film. Usually, a liner similar to the conventional liner 5 is selected. There is no limit to the method of attaching the liner of the present invention to the jacket body made of vinyl chloride or the like, such as by welding or adhesion, and there is no limit to the attachment area or attachment pattern of the two different sheets.

In an experiment using the jacket of the embodiment shown in FIG. 2, it was confirmed that the increase in dropout could not be counted even after 3 million passes at a rotational speed of 300 rpm. When the same disk used in the above experiment was placed in a conventional jacket and the test was conducted under the same conditions as above, an increase in dropout was observed from around 100,000 passes, and there were scratches of several μm on the disk surface. It has been observed that this occurs,
The usefulness of the present invention was confirmed.

Note that when the liner 6 and the liner 5 are used together, the recording area is always cleaned because of their high lubricity and high cleaning performance.

(Effects of the Invention) As described above, the present invention has the effect of stabilizing disk rotation and preventing damage to the disk surface. The industrial value of the present invention is extremely high as it has many advantages such as improved reliability and service life of flexible disks.

[Brief explanation of drawings]

FIG. 1 is a partially enlarged sectional view of an embodiment of the present invention.
Figures 2 and 3 are developed views of the jacket. FIG. 4 is a sectional view when a floppy disk is housed in the drive. FIG. 5 is a partially enlarged plan view of the conventional structure. FIG. 6 is a partially enlarged sectional view of a conventional conventional device. 1...pad, 2...jacket body, 3...
Disk, 4...Collection, 5...Liner, 6
...high lubricity and/or low coefficient of friction liner.

Claims (1)

[Claims] 1. In a jacket used for a flexible disk for magnetic recording, at least the inner part of the jacket that contacts the disk at the place where the jacket holding pad of the floppy disk driver comes into contact has a low coefficient of friction and/or high lubricity. A jacket for a flexible disk for perpendicular magnetic recording, characterized by having a liner made of material.