JPS60202538A - Magnetic disk - Google Patents

Abstract

PURPOSE:To improve the durability of a magnetic disk with no reduction caused in the film thickness of a lubricant even after working of a long period of time, by forming a groove of 0.2-0.5mm. width and 0.1-0.2mm. depth between an inner circumference clamp part and the most inner circumference floating assuring area part of a magnetic head in order to hold the lubricant. CONSTITUTION:A groove 3 is formed between an inner circumference clamp part and the most inner circumference area for assurance of head floating over a round of a disk 1. In this case, a diamond tool having a 0.08-0.4mm. blade edge diameter is used. Then a lubricant is applied sufficiently into the groove 3 and onto a magnetic film by a dipping or splaying method, and the optimum thickness is secured on the surface of the magnetic film by a wiping method. Thus a sufficient amount of lubricant is held in the groove 3. The thickness of a lubricant film is kept at about 95% initial value after 600hr for a magnetic disk medium containing a groove of 0.5mm. width and 0.1mm. thickness. Both a magnetic disk and a magnetic head are not injured despite >=50,000 CSS frequencies.

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field) The present invention relates to a magnetic disk, and particularly to a magnetic disk for use in a magnetic disk device of the Contact Starts V7 (hereinafter abbreviated as C88) system. □ (Prior Art) The C180,000 type magnetic disk device used for the external S storage device of a computer is used for the purpose of improving performance.

The magnetic disk used for this purpose is coated with a Jl agent in order to prevent the magnetic film from being worn out and damaged by magnetic contact. However, magnetic disks rotate at high speeds in order to shorten data access time and maintain a stable head flying height.

Therefore, when a magnetic disk storage device operates for a long time,
The problem is that the lubricant on the surface of the magnetic disk is scattered by the influence of centrifugal force, and the lubricant film becomes thinner than enough to prevent wear and damage caused by the magnetic head, increasing the risk of head cracking. □If extra lubricant was applied in consideration of the amount of lubricant that would be scattered during manufacturing, the magnetic head and magnetic disk would stick together, and the magnetic disk would not rotate when the magnetic disk drive was started. In some %A, the magnetic head vibrates even when it rotates, causing damage to the magnetic disk.
There are drawbacks to giving.

(Object of the Invention) The object of the present invention is to form a lubricant retaining groove between the circumferential clamp part and the magnetic head floating innermost circumferential guarantee area, so that the lubricant is only dispersed in an amount that is dispersed by centrifugal force during use. By automatically supplying the VH to the disk, this problem can be solved and a reliable high VH magnetic disk tube can be provided.

(Structure of the Invention) According to the present invention, a depth of 0.1 to 0.2 for holding #l lubricant is provided between the inner peripheral clamp portion and the innermost magnetic head floating guaranteed region s0.
Form a groove with a width of 5 mm and a width of 0.2 to 0.5 mm.
A magnetic disk with a characteristic characteristic is obtained.

(Example) Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a plan view of an embodiment of the present invention, and shows an inner peripheral clamp s2.
In order to form a groove 3t over one circumference of the disk between the innermost peripheral area 40 that guarantees head flight. Groove 3 has a cutting edge diameter of 0.08 to 0.
Processed with 4-O tire mondo pite. The lubricant is applied to the grooves and abrasive coating by spraying. Apply a cloth and wipe to obtain the optimum film thickness on the magnetic coating surface. However, 111f is enough for Hisashi.
lt agent is retained.

Next, the effects will be explained. The acceleration conditions for the acceleration test were derived from a theoretical analysis of the fluid film thickness t on the rotating disk and a friend theory solution.

Here, h is the film thickness in 1 hour, hQ is the initial film thickness, and the number of revolutions is multiplied by 3 (11000r,
p, m, ), external source [t-2 times (120'c) 1 Compared to normal use, the kinematic viscosity is t'/10.

纂2I! Q represents the change in the thickness of the synovial film over time for the conventional grooveless magnetic disk medium. After 600 hours, it becomes about /4 compared to the initial value. With a film thickness of this level, the number of times 088 was applied was several thousand times and the crack was 1.

The GA diagram shows the change in stagnation over time for a magnetic disk medium in which grooves with a radius of α5 and a depth of 0.1− are formed.

After 600 hours, the initial value of Meikosha was 095msigt, and the magnetic disk and magnetic head were not damaged even after 50,000 or more CSS operations.
．． 3 shows the change in the lubricant film thickness of the magnetic disk medium with the 05- ridge formed over time. (When the elapsed time reaches 10 hours, the lubricant film thickness suddenly increases and is about twice as large.) Since the lubricant film thickness is greater than 0, which causes an adhesion phenomenon between the magnetic disk and the magnetic head, the groove dimensions are 1;o, 2 to 0. 5 wm.

Depth: 0.1-0.2*w+ is optimal.

(Effects of the Invention) According to the present invention, as explained above, one radius α2 to α5■, #l and αl to 0.2-0 grooves are formed between the magnetic disk crank part and the innermost circumferential area for guaranteeing the flying of the magnetic head. By forming this, the lubricant OX thickness does not decrease even after long-term operation.
Endurance 1i, oJL (A nil disk is obtained.

[Brief explanation of drawings]

Prostitute 1 is a dud @ magnetic disk 1! Example plane-1 2nd
Figures 4 to 4 are detailed explanatory diagrams of the present invention. 1...Magnetic disk medium, 2...Baclumph s. 3...Groove, 4...The most circular area where the floating head is guaranteed. 1 side 'VJ2'

Claims (1)

[Claims] A depth of 0.1 to 0.2 mm for lubricant retention between the inner crank 1 part and the innermost magnetic head floating guarantee area, 5O12 to 0
．． 5) A magnetic disk characterized in that #1It-forms nine.