JPH06325564A - Magnetic disc unit - Google Patents

Abstract

PURPOSE:To prevent head crash due to the fine particles of drying agent by making a drying agent case located in the base plate of magnetic disc unit of a silicone rubber which passes the steam molecules. CONSTITUTION:A case 7 containing a drying agent 10 is made of a moisture permeable silicone rubber and disposed in a base plate 6. The interior of the base plate 6 is less moist than the interior of the case 7 and the difference of steam pressure appears between the interior and the exterior of the case 7. Consequently, the steam in the base plate 6 permeates the case 7 and absorbed by the drying agent 10 thus dehumidifying the interior of the base plate 6. The case 7 passes the steam molecules but does not pass the particles of drying agent having the diameter larger than that of the steam molecule. This structure prevents the head crash caused by the fine particles of drying agent.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic disk device which hermetically houses a magnetic disk, a magnetic head and a magnetic head positioning mechanism.

[0002]

2. Description of the Related Art FIG. 2 is a sectional view showing an example of a conventional magnetic disk device.

As shown in FIG. 2, a conventional magnetic disk device which hermetically houses a magnetic disk, a magnetic head, and a magnetic head positioning mechanism is a magnetic disk 11 mounted on a spindle 12 and rotating at a high speed. A magnetic head 13 for writing or reading information while floating while maintaining a minute gap between the magnetic disk 11 held by the arm 14 and the magnetic disk 11 rotating, and the magnetic head 13 is moved by moving the arm 14. Of the magnetic disk 11, the magnetic head 13, and the carriage 1.
5 is housed in the base plate 16 in a sealed manner.

A desiccant case 17 containing a desiccant 20 is contained in the base plate 16 for dehumidifying the inside. The desiccant case 17 is provided with a vent hole 18 communicating with the inside of the base plate 16, and an air filter 19 is attached to the vent hole 18.

The desiccant case 17 is formed of a plastic having almost no moisture permeability, and therefore the desiccant case 17 is formed.
The flow of gas between the inside of the base plate and the inside of the base plate 16 is
Only done via the vents 18 and the air filters 19. As the air filter 19, in order to prevent the desiccant 20 from scattering inside the base plate 16, a filter having a high dust collection efficiency is used.

The desiccant case 17 containing the desiccant 20 in the base plate 16 is housed in
By dehumidifying the inside of the base plate 16 with the desiccant 20, the magnetic disk 11 and the magnetic head 13 are
This is to prevent the adsorption of and by the magnetic disk 1
If the magnetic head 13 and the magnetic head 13 are attracted to each other, a high frictional force may be generated and the magnetic disk 11 may be damaged (this is called head crash).

[0007]

As described above, the conventional magnetic disk device is provided with a vent hole in the desiccant case in order to allow gas to flow between the desiccant case and the base plate. An air filter is attached to the pores to prevent the desiccant from scattering inside the base plate. However, even if an air filter with high dust collection efficiency is used, the dust collection efficiency is still 100%. %, Fine particles of desiccant debris permeate the air filter and scatter into the base plate, which penetrates between the magnetic disk and the magnetic head and causes a head crash. There is a problem.

[0008]

A magnetic disk device according to the present invention comprises a base plate for housing a magnetic disk, a magnetic head, and a magnetic head positioning mechanism, and a desiccant case housed in the base plate and containing a desiccant. In the magnetic disk device including the above, at least a part of the desiccant case is formed of a silicon rubber having moisture permeability of water vapor molecules.

[0009]

Embodiments of the present invention will now be described with reference to the drawings.

FIG. 1 is a sectional view showing an embodiment of the present invention.

The structure and operation of the magnetic disk 1, spindle 2, magnetic head 3, arm 4 and carriage 5 of the embodiment shown in FIG. 1 are the same as the structure and operation of the parts corresponding to the conventional example shown in FIG. And
It is housed in the base plate 6 in a sealed manner.

In order to dehumidify the inside of the base plate 6, a desiccant case 7 in which a desiccant 10 is hermetically sealed and incorporated.
Is housed. The desiccant case 7 is made of moisture-permeable silicon rubber.

Since the interior of the desiccant case 7 is dehumidified by the action of the desiccant 10, it has a lower humidity than the interior of the base plate 6. Therefore, inside the desiccant case 7 and inside the base plate 6 (outside the desiccant case 7)
And a difference in water vapor pressure is generated between the water vapor and the water vapor. In this way, the inside of the base plate 6 is dehumidified.

Desiccant case 7 made of silicone rubber
Has moisture vapor permeability of water vapor molecules, but does not permeate particles having a diameter larger than that of water vapor molecules, such as fine particles of desiccant fragments. Therefore, it is possible to prevent the head crash due to the fine particles of the desiccant.

[0015]

As described above, in the magnetic disk device of the present invention, the desiccant case is formed of the silicone rubber having the moisture permeability of water vapor molecules, so that the head crash due to the fine particles of the desiccant is completely prevented. Therefore, there is an effect that a highly reliable magnetic disk device can be obtained.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention.

FIG. 2 is a cross-sectional view showing an example of a conventional magnetic disk device.

[Explanation of symbols] 1/11 Magnetic disk 2/12 Spindle 3/13 Magnetic head 4/14 Arm 5/15 Carriage 6/16 Base plate 7/17 Desiccant case 10/20 Desiccant 18 Vent hole 19 Air filter

Claims (2)

[Claims] 1. A magnetic disk device comprising: a base plate for housing a magnetic disk, a magnetic head, and a magnetic head positioning mechanism; and a desiccant case housed in the base plate and containing a desiccant therein. A magnetic disk device, wherein at least a part of the magnetic disk device is formed of silicon rubber having moisture vapor permeability. 2. The magnetic disk drive according to claim 1, wherein the entire desiccant case is made of silicone rubber.