JPS62184685A - Magnetic disc device - Google Patents

Abstract

PURPOSE:To easily replace a gas adsorbing agent without deteriorating the reliability by containing the gas adsorbing agent to the atmosphere side in a flow path leading to a breathing hole and a breathing filter provided to an enclosed structure. CONSTITUTION:A containing box 107 incorporating the gas adsorbing agent 106 such as activated carbon is provided to the outside of the breathing hole 100, a high performance filter 101 and a pre-filter 102, and a flow path leading to the breathing hole 100 and the high performance filter 101 is constituted of a vent hole 108 formed to the box 107 to enter the adsorbing agent 106 into the flow path. The adsorbing agent 106 can be replaced while a cover 2 of the magnetic disk device is coupled to the base 1. Even if the containing box 107 is removed, since the high performance filter 101 acts onto the breathing hole 100, the replacement of the gas adsorbing agent 106 is executed not in a cleaned environment such as a complete clean room and it is executed easily even at a location where the magnetic disc device is placed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a sealed magnetic disk device with improved reliability.

[Prior art]

The recording density of a magnetic disk device increases as the distance between the magnetic disk medium surface and the recording/reproducing head (the flying clearance of the magnetic disk) decreases, so currently the flying clearance of the magnetic head is becoming smaller and smaller. It's coming. It is no exaggeration to say that progress in magnetic disk drives is due to improvements in technology for maintaining even smaller flying gaps stably and with high reliability. Keeping the inside of a magnetic disk device that houses a magnetic disk medium and a magnetic head in a completely clean state is one of the most important issues for stable flying of the magnetic head.

To achieve this, recent magnetic disk drives adopt a structure in which the magnetic disk medium, magnetic head, magnetic head positioning mechanism, etc. are housed in a sealed structure to prevent dust from entering from the outside. .

FIG. 3 is a sectional view schematically showing this type of conventional magnetic disk device with a closed structure. Reference numeral 1 indicates a base, and reference numeral 2 indicates a cover, and their joints are sealed with O-rings, gaskets, etc., and both form a closed container. 3
4 is a spindle hub, 4 is a magnetic disk medium stacked on the spindle hub 3, and 5 is a spindle shaft. 6 is a bearing that supports the spindle shaft 5 with respect to the base 1, and 7 is a magnetic fluid sealing mechanism that seals the gap between the base 1 and the spindle shaft 5.

8 is a rotor of the spindle motor, 9 is a stator of the spindle motor, 10 is a magnetic head positioning mechanism, and 11 is a bed arm on which a magnetic head (not shown in FIG. 3) is mounted at the tip.

On the other hand, 100 is a breathing hole that maintains the internal pressure of the sealed structure at the same pressure as the outside air, 101 is a high-performance filter (breathing filter) that removes dust from the air that enters and exits through the breathing hole 100, and 102 is a breathing hole 100 and High performance filter 1
This is a pre-filter that protects 01.

In such a magnetic disk drive, the connecting portion of the sealed structure is an O-ring or a gasket as described above, and the gap between the base 1 and the spindle shaft 5 is sealed with a magnetic fluid, so that the breathing hole 100 and the high Performance filter 1
01, the interior is completely shut off from the outside air except for the pre-filter 102.

The breathing hole 100 is provided in order to make the internal pressure, which changes during operation and stop of the magnetic disk device or in response to changes in environmental temperature, approximately equal to the outside air, and is designed to adjust the internal pressure distribution caused by the rotation of the magnetic disk medium 4. By placing the container near the lowest pressure point, the pressure inside the sealed container can always be maintained at a slightly positive pressure relative to the outside air while the device is operating, thereby preventing dust from entering from the outside. This allows for even more complete prevention.

Air entering through the breathing holes 100 is filtered by high performance filters (multiplexed if necessary);
This prevents dust from entering the inside of the magnetic disk drive.

However, it cannot be used against organic solvent mist emitted from wax used to clean floors, ultrafine dust such as toner used in laser printers, or trace amounts of corrosive gas contained in automobile exhaust gas. However, the above-mentioned filter using filter paper has the disadvantage that it cannot be filtered, but instead passes through the filter.

When such fine particles are mixed in, the fine particles adhere to and grow on the magnetic disk medium or the magnetic head, and there is a risk that the magnetic head and the magnetic disk medium will come into contact with each other, causing a so-called head crash. In addition, if corrosive gas gets mixed in, there is a risk that it will not only cause electrical problems such as poor continuity of internal components, but also various problems such as internal dust generation due to corrosion of parts and deterioration of magnetic media characteristics. There is.

As one method to solve this drawback,
No. 2273 discloses a magnetic disk device in which a filter containing activated carbon is installed in an air flow path in a closed room formed by a cover.

FIG. 4 is a cross-sectional view schematically showing the structure, and 103 is a storage box for activated carbon 104 installed inside the cover 2, and 105 is a storage box provided in the storage box 103 to prevent the activated carbon 104 from being discharged from the air hole. It is a filter (filter paper).

With this configuration, outside air entering through the breathing hole 100 flows into the inside of the magnetic disk device via the activated carbon 104. Activated carbon adsorbs minute mist and specific gases, so even if the aforementioned particles or gases are mixed into the outside air, they can be removed.

However, if harmful mists or fine particles mixed in the outside air are identified, activated carbon can be installed to efficiently adsorb them, but especially when corrosive gases are targeted, the environment in which the magnetic disk drive is installed Depending on the type of corrosive gas,
The concentration often differs, and even if the installation location is the same, the environmental conditions of the building where it is installed may be different, for example, due to the construction of a new factory nearby, etc.
Or it may change due to sudden increase in traffic volume, etc.

By the way, there are various kinds of gas adsorbents such as activated carbon, depending on the adsorbed gas. For example, ordinary activated carbon has extremely low adsorption capacity for low-boiling hydrocarbons, ammonia, NO9, etc. Furthermore, for example, in order to deodorize ammonia, an adsorbent whose material is treated with sulfuric acid is suitable. In this way, the importance of selecting the most suitable activated carbon depending on the target gas is shown, for example, in the literature "Air Cleaner Vol. 10 No. 6 P.
12" etc. are also detailed.

In the conventional magnetic disk drive equipped with a filter containing activated carbon as shown in Fig. 4, when it becomes necessary to change the type of activated carbon in response to changes in the external environment, or when the concentration of harmful gases contained in the outside air increases. If it becomes necessary to replace the activated carbon due to increased adsorption capacity, the activated carbon filter is installed inside the cover 2, so if the activated carbon filter is installed inside the cover 2, replace the cover 2 with the base 1
It is necessary to remove it from the

That is, since the sealed container kept in a clean state must be completely opened to the outside air, this work must be carried out in the same cleaning environment as the disk device assembly factory. Usually, there is no completely lean room at the location where the magnetic disk drive is installed, and in this case, the magnetic disk drive must be taken back to the factory and the above-mentioned work must be carried out.

Furthermore, opening and reconnecting the joint between the base 1 and the cover 2 of the magnetic disk drive causes a slight distortion in the base I, and there is a risk that the reproducibility of the head positioning mechanism 10, which performs precise positioning, will be significantly deteriorated. be.

That is, it is known that the performance of the head positioning mechanism 10, which positions the recording track with submicron precision, deteriorates due to minute deformations caused by temperature rise, and engineers in this field call it a "thermal off". This is an important technical issue as a countermeasure against thermal tracks, but once the base and cover are combined, the distortion state becomes different when they are released and recombined, resulting in the same off-track as the above-mentioned "thermal off-track". Become. Therefore, when the base and cover are recombined, it is usually necessary to re-initialize the various information recorded on the magnetic disk medium.

As explained above, the conventional apparatus has the serious drawback that the work required to replace the activated carbon is enormous, and the replacement time and replacement cost are extremely large.

[Purpose of the invention]

The object of the present invention is to solve the above-mentioned conventional drawbacks, and to provide a magnetic material that allows the gas adsorbent to be replaced extremely easily and without impairing reliability, even if it becomes necessary to replace the gas adsorbent. The objective is to provide a disk device.

[Structure of the invention]

To this end, the present invention accommodates a magnetic disk medium for recording information and a magnetic head for recording and reproducing information on the medium in a sealed structure, and adjusts the air pressure inside the sealed structure to be approximately equal to the outside air. In a sealed magnetic disk drive equipped with a breathing hole and a breathing filter that filters out dust that enters through the breathing hole, a flow path is provided that leads from the outside air to the breathing hole and the breathing filter, and the It is constructed by storing a gas adsorbent on the outside air side.

〔Example〕

Examples of the present invention will be described below. FIG. 1 is a sectional view showing one embodiment of the present invention, and the same parts as shown in FIGS. 3 and 4 are given the same reference numerals. In this embodiment, a storage box 1 containing a gas adsorbent 106 such as activated carbon is placed on the outside of the breathing hole 100, the high-performance twister 101, and the pre-filter 102, that is, on the outside of the cover 2.
07 is provided, and this storage box 107 is provided with a ventilation hole 1 that communicates with the outside air.
08, and the ventilation hole 108 constitutes a flow path leading from the outside air to the breathing hole 100 and the high-performance filter 101, and the gas adsorbent 106 enters the flow path.

Because of this structure, when it becomes necessary to replace the gas adsorbent 106, the cover 2 of the magnetic disk drive
Replacement work can be performed while the base 1 remains connected to the base 1. That is, as shown in FIG.
The storage box 107 of No. 6 is installed externally on the cover 2, and even when the storage box 107 is removed, the high-performance filter 101 is still functioning for the breathing hole 100, so it is easy to replace the gas adsorbent 106. It does not need to be in a clean environment such as a completely clean room, and can be easily carried out at the location where the magnetic disk device is installed. Furthermore, even if the item is taken back to the factory, the replacement work can be carried out with the cover 2 and base 1 still connected, so there is no need to initialize the recorded information as described above, so the replacement time and cost are reduced. It has the advantage of being done.

FIG. 2 is a partial view of essential parts showing another embodiment of the present invention. In this example, a gas adsorbent 106 is stored in a storage box 109 that also functions as a pre-filter 102', and a ventilation hole 111 that communicates with the outside air is formed in a lid 110 that closes the storage box 109. The ventilation hole 111 can also be provided in the storage box 109 so as to communicate with the outside air.

In this example as well, the same function as in the case of FIG.
This can be easily done by opening the lid 110 of the breather 9, and since the high performance filter 101' that closes the breathing hole 10 is functioning, no dust will get inside.

Various other modifications can be considered to the storage structure of the gas adsorbent, but when replacing the gas adsorbent or the storage box containing the gas adsorbent, contamination may occur through the breathing hole provided in the sealed structure. Any structure is sufficient as long as it can function as a filter capable of filtering out dust, and for example, the structure shown in FIG.
Needless to say, it may be arranged in

〔Effect of the invention〕

As explained above, according to the present invention, a gas adsorbent that efficiently adsorbs gases harmful to magnetic disk drives is provided in a sealed structure from the outside air, and is provided in a flow path leading to a breathing hole and a breathing filter. Because of this arrangement, even if it becomes necessary to replace the gas adsorbent in response to changes in the external environment, there is an advantage that the replacement work can be performed extremely easily and without impairing reliability.

[Brief explanation of drawings]

O' Fig. 1 is a sectional view of a sealed magnetic disk device according to one embodiment of the present invention, Fig. 2 is a partial sectional view showing the main parts of a magnetic disk device of another embodiment, and Fig. 3 is a conventional one. FIG. 4 is a sectional view of a sealed magnetic disk device with a conventional activated carbon filter. DESCRIPTION OF SYMBOLS 1...Base, 2...Cover, 3...Spindle hub 4...Magnetic disk medium, 5...Spindle shaft 6...Bearing, 7...Magnetic fluid seal mechanism, 8
... Rotor of spindle motor, 9... Stator of spindle motor, 10... Magnetic head positioning mechanism, 11... Head arm. 100.100'...breathing hole, 101.101'...
・High performance filter (breathing filter)・102.102・
...Prefilter, 103...Activated carbon storage box, 1゜...Activated carbon, 105...Filter, 106...Gas adsorbent, 107...Gas adsorbent storage box, 108.
... Ventilation hole formed in the storage box, 109 ... Storage box with a pre-filter function, 110 ... Lid of the storage box, 1
11...Vent hole formed in the lid. Agent Patent Attorney Tsuneaki Nagao Figure 1 101'100'102' 2 Figure 8

Claims (1)

[Claims] (1) A magnetic disk medium for recording information and a magnetic head for recording and reproducing information on the medium are housed in a sealed structure, and a breathing hole is provided to adjust the air pressure inside the sealed structure to be approximately equal to the outside air. and a breathing filter for filtering dust that enters through the breathing hole, a flow path leading from outside air to the breathing hole and the breathing filter is provided, and a flow path is provided on the outside air side of the flow path. A magnetic disk device characterized by containing a gas adsorbent.