JPH065598B2 - Magnetic disk device - Google Patents

Description

Description: (a) Technical Field of the Invention The present invention relates to a magnetic disk device, and more particularly, to a lubricating property of a lubricating film coated on the surface of a magnetic disk mounted in the device and a floating of a magnetic head. The present invention relates to a device configuration capable of always maintaining a stable state.

(b) Background of Technology In a magnetic disk device, in recent years, high density recording has been achieved by thinning the magnetic film of the magnetic disk or lowering the flying height of the magnetic head with respect to the magnetic disk. In addition to the low flying height of the magnetic head, the magnetic head is in contact with the surface of the magnetic disk when stopped.
The so-called CSS (Contact S
As the adoption of the (tart stop) method progresses, the contact and sliding at the time of starting and stopping the rotation of the magnetic disk are likely to cause head crush such as wear and damage on the magnetic head and the surface of the magnetic disk. It is common practice to apply a lubricant to the surface of the disk or to apply a surface treatment such as coating a lubricant film.

(c) Problems with Prior Art Meanwhile, by adopting the CSS method, the magnetic disk device is being changed to a hermetic type in order to prevent a head crash caused by mixing of dust. However, in such a sealed magnetic disk device, a temperature rise of 60 to 70 ° C. is unavoidable in the device due to windage loss due to the high speed rotation of the magnetic disk, and the magnetic disk surface is applied due to the temperature rise. There is a problem that the lubricating film evaporates and disappears, and its lubricating characteristics deteriorate, and there is a demand for a lubricating film having excellent heat resistance that can solve such a problem.

However, in response to such claims, typical lubricants that have been conventionally used are, for example, hydrocarbons such as paraffin, higher fatty acids, and higher fatty acid esters, or fluorocarbon-based oils that are fluorides thereof, such as Si. There are silicone-based oils that consist of -Si bond groups. These lubricants are
Or, it is used in a complex form, but a hydrocarbon-based lubricant, especially a lubricating film made of higher fatty acid or its ester compound, has excellent lubricating properties, and therefore has a very remarkable effect in improving lubricating durability. On the other hand, there is a drawback in that the heat resistance is inferior such that it gradually evaporates and disappears in an atmosphere of about 60 ° C. and then loses lubricity. Further, a lubricating film made of a fluorocarbon oil or a silicone oil has excellent heat resistance, but has a drawback in that the lubricating characteristics are inferior. An ultra-thin lubricating film with excellent heat resistance cannot be obtained, making it difficult to achieve high-density recording without head crash problems.

Therefore, the inventors of the present invention suppress the scattering and disappearance of a lubricating film made of a higher fatty acid, which has poor heat resistance on the surface of the magnetic disk under a temperature rise, by filling the sealing device with a vapor of a lubricant made of a higher fatty acid, for example. Then, a method that can maintain its lubricity stably over a long period of time was previously proposed.

However, in such a method, when the vapor of the lubricant is generated and filled in the sealing device, there is a phenomenon that the lubricant fine particles are scattered and adhere to the magnetic disk surface together with the generated lubricant vapor. However, there is a drawback that the flying state of the magnetic head becomes unstable.

(d) Object of the invention In order to solve the above-mentioned conventional drawbacks, in order to prevent the lubricating film on the surface of the magnetic disk from scattering and disappearing due to a temperature rise in the device, a lubricant evaporation source provided An object of the present invention is to provide a magnetic disk device that prevents the fine particles of the agent from scattering, maintains the durability of the lubricating film on the surface of the magnetic disk at a high temperature at all times, and stabilizes the flying state of the magnetic head. It is what

(e) Configuration of the invention According to the present invention, according to the present invention, in a magnetic disk device comprising a magnetic disk mounted on a rotary drive mechanism and sealing the magnetic disk with an airtight container, in the airtight container, A circulating agent evaporation source that generates a lubricant vapor by being exposed to the environment of a hot air flow generated near the surface of the magnetic disk when the magnetic disk is driven to rotate, and a lubricant fine particle scattering prevention at the circulating agent evaporation source. This is achieved by providing a magnetic disk device characterized by being provided with means.

(f) Embodiments of the Invention Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a sectional view conceptually showing one embodiment of a magnetic disk device according to the present invention. In the figure, reference numeral 1 denotes a magnetic disk having a surface facing a magnetic head 2 coated with a lubricating film (not shown), and 3 a hub mechanism in which a plurality of magnetic disks 1 are integrally supported and mounted on a disk rotation drive mechanism 6. Reference numeral 4 denotes a central ventilation hole formed at the center of the hub mechanism 3.
Is a ventilation small hole that communicates with the central ventilation hole 4 to let out a circulating atmosphere between the magnetic disks 1, 7 is a head positioning mechanism, 8 is an airtight container, and 10 is a central ventilation hole 4 of the hub mechanism 3.
It is a circulation atmosphere circulation portion provided in the base portion 9 so as to communicate with the. A lubricant that easily evaporates by being exposed to a hot air flow generated by windage when the magnetic disk 1 rotates at high speed as shown in FIG. A lubricant 22 made of behenic acid, which is one of the higher fatty acids, is contained in the container 21, and a means for preventing scattering of lubricant fine particles, for example 0.3 μm, is provided in the opening portion thereof.
A lubricant evaporation source 11 provided with a particle scattering prevention filter (Kondo Kogyo: absolute filter, etc.) 23 capable of capturing particles of m or less with a probability of 99.97% or more is installed. 12 is a dustproof filter.

By configuring the magnetic disk device in this way, when the disk rotation drive mechanism 6 is driven to rotate the magnetic disk 1 at a high speed, the hot air flow generated by the wind loss during the high speed rotation is indicated by the arrow in the figure. As shown in the drawing, the temperature inside the airtight container 8 rises by circulating, and the lubricant evaporation source 11 exposed to the circulating hot air stream is also heated and the lubricant 22 evaporates.

At this time, the fine particles of the lubricant are also scattered, but the fine particles of the lubricant are captured by a filter 23 for preventing dispersion of the fine particles attached to the opening of the container 21, and only the lubricant vapor is circulated in the circulation atmosphere provided in the base portion 9. From the portion 10 through the central ventilation hole 4 of the hub mechanism 3, it flows out between the magnetic disks 1 through the respective ventilation small holes 5 communicating with the hub mechanism 3, and the airtight container 8 is filled.

Therefore, the vapor pressure of the lubricating film on the surface of each rotating magnetic disk 1 evaporates due to the temperature rise due to windage and the vapor pressure of the lubricant vapor are substantially in equilibrium, and the lubricating film on the surface of each magnetic disk 1 is in equilibrium. Is maintained in a steady state with good lubrication properties. Conventionally, when the particle scattering prevention filter 23 is not applied, when the lubricant particles adhere to the surface of the magnetic disk 1 and the magnetic head passes through the adhered portion, the magnetic head 2 instantaneously contacts the surface of the magnetic disk 1. There is a phenomenon in which the magnetic head 2 is attracted and the floating state of the magnetic head 2 becomes unstable. This phenomenon can be detected by attaching an AE sensor to the magnetic head 2 side. Further, when the adhesion of the lubricant fine particles to the surface of the magnetic disk further progresses, destabilization of the flying state of the magnetic head 2 increases, and finally a head crash failure occurs on the surface of the magnetic disk 1. According to the present invention, such an inconvenient problem is solved and the flying state of the magnetic head with respect to the magnetic disk can be always stabilized.

Incidentally, in the above examples, as an example of the case where a filter is used as the scattering preventing means for capturing the scattered lubricant fine particles, the present invention is not limited to this example, for example, the slits are staggered. What is necessary is just to be able to capture the lubricant fine particles, such as by forming the lubricant fine particles in a multi-stage configuration. Further, in this embodiment, the lubricant vapor is provided between the magnetic disks 1 from the circulation atmosphere circulation portion 10 provided in the base portion 9 through the central ventilation hole 4 of the hub mechanism 3 and the respective ventilation small holes 5 communicating therewith. Although the description has been made for the magnetic disk device having the circulating circulation path, it is needless to say that the present invention can be applied to a sealed magnetic disk device having no such airflow circulation path.

(g) Effects of the Invention As is apparent from the above description, according to the magnetic disk device of the present invention, the lubricating film on the surface of the magnetic disk mounted in the sealing device and being rotationally driven by the simple improved structure. Can always be maintained in a steady state having good lubrication characteristics, and the flying state of the magnetic head with respect to the magnetic disk can be always stabilized. Therefore, it is extremely advantageous when applied to a magnetic head having a low flying height and a sealed magnetic disk device adopting a CSS method or the like.

[Brief description of drawings]

FIG. 1 is a sectional view conceptually showing one embodiment of the magnetic disk device according to the present invention, and FIG. 2 is a lubricant evaporation provided with a means for preventing scattering of lubricant fine particles installed in the magnetic disk device of FIG. It is an expanded sectional view showing a source. In the drawings, 1 is a magnetic disk coated with a lubricating film,
2 is a magnetic head, 3 is a hub mechanism, 4 is a central ventilation hole, 5 is a ventilation small hole, 6 is a disk rotation drive mechanism, 7 is a head positioning mechanism, 8 is an airtight container, 9 is a base part, and 10 is a circulating atmosphere. A flow path, 11 is a lubricant evaporation source, 12 is a dustproof filter, 21 is a container, 22 is a lubricant, and 23 is a particle scattering prevention filter.

Claims (1)

[Claims] 1. A magnetic disk mounted on a rotary drive mechanism,
In a magnetic disk device in which the magnetic disk is hermetically sealed by an airtight container, by exposing the airtight container to the environment of a hot air flow generated near the surface of the magnetic disk as the magnetic disk is driven to rotate. A magnetic disk device comprising a lubricant evaporation source for generating a lubricant vapor, and a lubricant particle scattering prevention means attached to the lubricant evaporation source.