JPH0121558B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Technical Field of the Invention The present invention relates to a magnetic disk device, and in particular, to constantly improve the lubricating properties of a lubricating film coated on the surface of a magnetic disk mounted in the device in a steady state. The present invention relates to an apparatus configuration that allows maintenance of the following conditions.

(b) Background of the Technology In recent years, in magnetic disk devices, attempts have been made to increase the recording density by making the magnetic film of the magnetic disk thinner or multilayered, and lowering the flying height of the magnetic head. In addition to lowering the flying height of the magnetic head, the magnetic head is in contact with the surface of the magnetic disk when stopped, and as the rotational speed increases, the magnetic head is slightly raised.
As the so-called CSS (Contact Start Stop) method is increasingly adopted, head crushing such as wear and damage on the surface of the magnetic head and magnetic disk is likely to occur due to contact sliding when starting and stopping rotation. It is common practice to apply special surface treatments such as applying a lubricant to the disk surface or coating it with a lubricant film.

(c) Prior art and problems By the way, as the recording density of magnetic disk devices increases, lowering the flying height of the magnetic head becomes more and more important, and the lubricating film applied to the surface of the magnetic disk is gradually becoming thinner. requires an extremely thin lubricant film of around 100Å with excellent lubrication durability. On the other hand, with the adoption of the CSS method, magnetic disk devices are being shifted to sealed types in order to prevent head crashes caused by contamination with dust. However, in such a sealed magnetic disk device, the temperature inside the sealed device rises due to air friction caused by the high-speed rotation of the magnetic disk, so the atmosphere inside the device is usually controlled by a self-circulation air cooling method. Even so, the temperature inside the device inevitably rises to 60-70℃, and due to this temperature rise, the lubricant film on the magnetic disk surface evaporates and disappears, causing the lubrication to deteriorate. There is a disadvantage that the characteristics deteriorate, and there is a strong demand for heat resistance that can eliminate this disadvantage.

However, in response to these demands, typical lubricants conventionally used to form a lubricant film on the surface of a magnetic disk include paraffin,
There are hydrocarbons such as higher fatty acid alcohols, higher fatty acids, and higher fatty acid esters, fluorocarbon oils that are their fluorides, and silicone oils that have Si-Si bond groups.These lubricants can be used alone or in combination. However, among the above lubricants, hydrocarbon-based lubricants, especially the lubricating film formed by higher fatty acids and their esters, have excellent lubricating properties and can improve lubrication durability. However, on the other hand, it has the disadvantage of poor heat resistance, such as gradual evaporation and loss of lubricity in an atmosphere of about 60°C. In addition, lubricating films formed with fluorocarbon oils, silicone oils, etc. have excellent heat resistance properties, but they all have film properties with only advantages and disadvantages, such as poor lubrication properties. There is.

Therefore, it is not only extremely difficult to obtain an ultra-thin lubricant film with excellent lubrication durability and heat resistance for high recording density, but also magnetic disks coated with such a lubricant film cannot be used as sealed magnetic disks. When used in a disk device, it has been difficult to perform stable high-density recording or reproduction without head crash failure.

(d) Purpose of the Invention In view of the above-mentioned conventional drawbacks, the present invention suppresses evaporation and disappearance of the lubricant film on the surface of a magnetic disk rotated in a sealed magnetic disk device, thereby maintaining the lubricant film with always good lubrication properties. It is an object of the present invention to provide a novel magnetic disk device that can maintain a steady state having the following characteristics.

(e) Structure of the Invention According to the present invention, the present invention provides an apparatus structure in which a magnetic disk integrally supported by a hub mechanism is attached to a rotational drive mechanism, and the magnetic disk is sealed in an airtight container. By providing a magnetic disk device characterized in that a lubricant vapor generation source and a heating means for heating the generation source to generate lubricant vapor are provided in the airtight container. achieved.

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

The drawing is a sectional view of a main part conceptually showing an embodiment of a magnetic disk device according to the present invention. In the figure, 1 is a magnetic disk whose surface facing the magnetic head is coated with a lubricant film (not shown); 2 is a hub mechanism in which a plurality of magnetic disks 1 are integrally supported and is attached to a disk rotation drive mechanism 5; Reference numeral 3 indicates a central ventilation hole drilled in the center of the hub mechanism 2, 4 indicates a small ventilation hole that communicates with the center ventilation hole 3 and allows circulating atmosphere to flow out between each magnetic disk 1, 6 indicates a head positioning mechanism, and 7 indicates a The airtight storage container 8 is a circulating atmosphere distribution hole provided in the base portion 9 so as to communicate with the central ventilation hole 3 bored in the center of the hub mechanism 2. A source container 11 containing a lubricant generating source 10 that generates lubricant vapor at a temperature of ~70° C. and a heating means 12 such as an electric heater are arranged integrally. Further, a filter 13 is disposed on the right side of the lubricant generating source 10 as shown in the figure.

Note that in general, in a magnetic disk device, the temperature of the surface of the magnetic disk 1 after starting rotation becomes considerably higher than the temperature of the atmosphere surrounding the magnetic disk 1 when it quickly rises, and the temperature of the surface of the magnetic disk 1 increases rapidly. Even when the temperature of the magnetic disk 1 remains constant, it is about 5 to 10 degrees Celsius higher than the temperature of the atmosphere surrounding the magnetic disk 1, that is, the temperature of the atmosphere that has risen due to air friction caused by the high speed rotation of the magnetic disk 1. . Therefore, in the magnetic disk device configured as described above, the disk rotation drive mechanism 5 is driven to rotate the magnetic disk 1.
At the same time as the lubricant vapor generating source 10 is heated by the heating means 12, the lubricant vapor can be evaporated. The amount of the generated lubricant vapor increases as the magnetic disk 1 rotates at high speed, and as shown by the arrow in the figure, the lubricant vapor circulates and flows into the circulating atmosphere distribution hole 8 provided in the base portion 9. Along with the air flow, the lubricant vapor passes through the filter 13 to remove dust such as lubricant, large particles of lubricant vapor, etc., and becomes clean lubricant vapor. The liquid flows out between the magnetic disks 1 through the small ventilation holes 4 communicating with the magnetic disks 1 and circulates in the airtight container 7 so as to surround the magnetic disks 1.

In this case, from the time when the magnetic disk 1 starts rotating until the temperature rise becomes gradual, the magnetic disk 1 is heated so that the amount of evaporation of the lubricant vapor is greater than the predetermined amount of evaporation during steady high-speed rotation. By controlling the temperature of the means 12 by a program control method or the like, and by arranging a temperature sensor 14 for controlling the temperature of the heating means 12 close to the magnetic disk 1, the temperature increase of the magnetic disk 1 can be coped with. This makes it possible to control the amount of evaporation of lubricant vapor.

Therefore, the vapor pressure of the circulating lubricant vapor surrounding the lubricant film on the surface of each rotating magnetic disk 1 and the vapor pressure when the lubricant film evaporates due to temperature rise due to air friction during high-speed rotation are approximately: It becomes an equilibrium state,
As a result, the lubricating film on the surface of each rotating magnetic disk 1 can be easily maintained in a steady state with good lubrication properties.

In the above embodiment, the lubricant is applied not only to the surface of the magnetic disk 1 inside the airtight container 7 but also to other functional parts.
The lubricating film is so thin that it does not impair the functionality of the device. Furthermore, if a porous member with a large surface area and good impregnability is separately disposed in the circulating atmosphere distribution hole 8 provided in the base portion 9, the lubricant vapor that fills the airtight container 7 is required. If the amount becomes excessive, it is possible to adjust and stabilize the amount of steam by absorbing it into the member.

(g) Effects of the Invention As is clear from the above explanation, the structure of the magnetic disk device according to the present invention can lubricate the surface of the magnetic disk installed in the device and being rotated by a simple improved configuration. It has the excellent advantage that evaporation and loss of the film is suppressed, and the thickness and lubricating properties of the lubricating film can always be maintained in a good steady state. Therefore, it is extremely advantageous to apply this type of magnetic disk device or a sealed magnetic disk device that uses a low-flying magnetic head, a CSS method, or the like.

[Brief explanation of drawings]

The drawing is a sectional view of a main part conceptually showing an embodiment of a magnetic disk device according to the present invention. In the drawings, 1 is a magnetic disk coated with a lubricating film, 2 is a hub mechanism, 3 is a center ventilation hole, 4 is a small ventilation hole, 5 is a disk rotation drive mechanism, 6 is a head positioning mechanism, 7 is an airtight container, Reference numeral 8 indicates a circulating atmosphere distribution hole, 9 indicates a base portion, 10 indicates a lubricant vapor generation source, 11 indicates a source container, 12 indicates heating means, 13 indicates a filter, and 14 indicates a temperature sensor.

Claims (1)

[Claims] 1. In an apparatus configuration in which a magnetic disk integrally supported by a hub mechanism is attached to a rotational drive mechanism, and the magnetic disk is sealed in an airtight container, a lubricant source and a lubricant are provided in the airtight container. A magnetic disk device comprising a heating means for heating a lubricant generating source to generate lubricant vapor.