JPS62175986A - Fixed magnetic disk device - Google Patents

Abstract

PURPOSE:To record and reproduce information with high density, and to prevent the drop of the reliability of information by enclosing the gas having a low viscosity into a container for holding hermetically the inside, and providing as a part of the container, a pressure variation absorbing plate which is deformed by a pressure difference between the external pressure and the internal pressure of the container and eliminates this pressure difference. CONSTITUTION:Air of a pressure absorbing chamber 3a and a device chamber 100a is discharged from a low viscosity gas enclosing port 3b, and in turn for instance, gas having a low viscosity gas such as gaseous helium, etc., as a composition, or a low viscosity gas is injected, and the low viscosity gas enclosing port 3b is sealed by a sealing tool 6. When the internal pressure of a fixed magnetic disk device 10 becomes larger than the external pressure, a pressure variation absorbing plate 3 is extended to the air side, namely, the opposite side to the pressure absorbing chamber 3a, and absorbs and releases the rising of the internal pressure. On the other hand, when the internal pressure of the fixed magnetic disk device 10 becomes smaller than the external pressure, the pressure variation absorbing plate 3 is extended to the inside of the fixed magnetic disk device 10, namely, the pressure absorbing chamber 3a side, and the drop of the internal pressure is released.

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention relates to a low-viscosity gas used to finely control the flying height of a flying slider of a magnetic disk drive using the principle of a dynamic pressure gas axis. The present invention relates to a fixed magnetic disk device that maintains a stable atmosphere composition.

[Conventional technology]

Figure 3 shows, for example, a conventional air-sealed type fixing device described in Nikkei Electronics (February 25, 1985, pp. 169-190, "Small Winchester disk device rapidly rising on the steps of increasing capacity"). 1 is a schematic cross-sectional view of a magnetic disk device. In the figure, 100 is a box-shaped sealed lower container with an opening at the top, 101 is a sealed upper container that covers the opening, and both are connected using a rubber packing 102 and a fastener 103. Forms an airtight container. 104 is a motor such as a spindle motor, and 105 is a rotating shaft 10 of the motor 104.
41 is a magnetic disk mounted thereon; 106 is a signal control unit for signal control as a control circuit for a fixed magnetic disk device;
107 is a helad arm, 108 is a flying slider attached to the tip of the head arm 107, and 109 is a magnetic head provided on the flying slider 108.

110 is a fixed magnetic disk device, numbers 100 to 1
It is composed of the components indicated by 09. Note that cords (not shown) such as a power cord are externally connected to the main body of the magnetic disk drive, but these cords are connected directly or via connectors, and their airtightness is maintained sufficiently.

Next, the operation will be explained. The motor 104 rotates under the control of the signal control unit 106, and the magnetic disk 105 also rotates. Due to the viscous air resistance caused by the rotation of the magnetic disk 1050, the floating slider 108 flies a short distance away from the surface of the magnetic disk 105.

Due to the floating of this flying slider 108, the magnetic head 109
The magnetic disk 105 also floats, and its magnetic gap is positioned at a small distance from the recording surface of the magnetic disk 105. In this state, the magnetic disk 105 is
Recording and reproduction of information is performed. At this time, of course, the magnetic head 105 moves in the radial direction of the magnetic disk 1050 by moving the head arm 107 in the radial direction of the magnetic disk 1050 under the control of the signal control unit 106.
50, located on two predetermined points.

Such an air-sealed fixed magnetic disk device 110
Here, for convenience of assembly, the sealed container is divided into two parts, a sealed lower container 100 and a sealed upper container 101, and the sealed lower container 100 and the sealed upper container 101 are sealed by a highly elastic rubber packing 102. . In this case, the fixed magnetic disk device 110 inside the packing 102
The atmosphere inside and the atmosphere outside Patsukin 102 are both K.
l! Since the composition is the same as that of air, which is 79% elemental and 21% oxygen, the temperature of the fixed magnetic disk drive 110 may rise due to the drive/stop of the fixed magnetic disk drive 110, or the fixed magnetic disk drive 1
The composition of the atmosphere inside the fixed magnetic disk drive 110 does not change due to temperature changes at the installation location of the fixed magnetic disk drive 110.

In addition, in order to prevent dew condensation inside the fixed magnetic disk unit f110, it is necessary to place a desiccant inside.In this case, moisture will enter through the packing 102, but the material of the packing 102 A dry state can be maintained by appropriately selecting the width and amount of desiccant.

By the way, using such a device, the floating slider 108
In order to record information at high density by stably controlling the flying height of the magnetic head 109 to be smaller than the flying height by air, the Japan Society of Mechanical Engineers 932nd Annual Conference Proceedings A350-2 (1985 For example, it is possible to use a low-viscosity gas such as helium gas sealed inside the fixed magnetic disk drive 110, as described in 103 Slider Floating Characteristics in a Helium-Air Mixed Gas (August 24, 2013). .

[Problem that the invention seeks to solve]

Conventional fixed magnetic disk drives are configured as described above, so if the flying height of the flying slider is kept small and stable, then a low-viscosity gas such as helium gas is filled in the drive. Since the composition of the surrounding atmosphere and the low-viscosity gas inside the device are greatly different, the low-viscosity gas tends to gradually escape into the atmosphere outside the device.In particular, the internal pressure due to the heat generated when the drive Φ of the magnetic disk device itself stops. When the internal pressure increases and decreases due to a rise and fall in air pressure or a change in ambient temperature, low-viscosity gas tends to escape to the atmosphere outside the device or enter the device, causing the atmosphere inside the device to deteriorate over a long period of time. It is difficult to prevent changes in composition, and there are problems in that the flying height of the flying slider gradually increases over a long period of time, degrading the performance of the device.

The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a fixed magnetic disk device that can maintain the composition of the gas atmosphere within the device over a long period of time without causing any change in composition.

[Means for solving problems]

The fixed magnetic disk device according to the present invention houses a main body of the device for recording and reproducing information inside and keeps the inside airtight from the outside. A pressure fluctuation absorbing plate is provided as a part of the container, which is filled with a low viscosity gas and deforms due to the pressure difference between the external pressure and the internal pressure of the container to eliminate this pressure difference.

[For production]

The fixed magnetic disk device according to the present invention has a structure that allows the gas inside the container to expand and contract due to heat release when the main body of the device is driven and stopped, or due to the expansion and contraction of the gas inside the container due to changes in the temperature of the installation environment. Absorbs pressure changes by deforming the pressure fluctuation absorption plate and changing the volume of the container, eliminating pressure differences between the inside and outside of the container, and preventing the low viscosity gas sealed inside the container from leaking out of the container. .

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a cross-sectional side view showing a schematic configuration of a fixed magnetic disk device according to an embodiment of the present invention.

In this figure, the parts with the same symbols as those in FIG. 3 are the same as those in the prior art, and therefore their explanation will be omitted. 1 is a sealed upper container having holes 2 for gas inflow and outflow, the edge of which is balanced with the edge of a sealed lower container 100 via a gasket 102, and is secured using a fastener 103 such as a bolt. The upper opening of the sealed lower container 100 is covered by being integrally combined with the lower sealed container 100. Reference numeral 3 denotes a pressure fluctuation absorbing plate disposed at the upper part of the sealed upper container 1, and is made of, for example, a thin aluminum plate, rising in a step-like manner from the center to the periphery, and further extending to the outer periphery. It's going down like a staircase.

This pressure fluctuation absorbing plate 3 is fixed on the sealed upper container 1 using the above-mentioned fastener 103, and its periphery is fixed to the sealed upper container 1 with an adhesive or the like for airtightness. The pressure absorption chamber 3a formed by the pressure fluctuation absorbing plate 3 and the sealed upper container 1 formed in this way is the device chamber 1 formed by the sealed lower container 100 and the sealed upper container 1 and K.
00a through hole 2. Reference numeral 4 designates a lid body as a container-shaped protective cover having a hole 5, the edge of which abuts against the upper surface of the periphery of the sealed upper container l, and the abutting surface is airtightly fixed using an adhesive or the like. Pressure fluctuation absorption plate 3
is covered and protected. Reference numeral 10 denotes a fixed magnetic disk device, which is composed of the above-mentioned components.

FIG. 2 is a top view showing the detailed structure of the above-mentioned pressure fluctuation absorbing plate and the like. In the figure, 3b is a low viscosity gas inlet provided in the pressure fluctuation absorbing plate 3, and 6 is a low viscosity gas inlet 3b.
It is a sealing tool for sealing.

Next, only the main parts of the method of assembling this device will be explained.

First, the lid body 4 is not attached, and the air in the pressure absorption chamber 3a and the device chamber 100a is discharged from the low-viscosity gas filling port 3b, and instead, a gas having a composition of low-viscosity gas such as helium gas is used. Or low viscosity gas is injected. After this injection, the low viscosity gas filling port 3b is sealed with a sealing tool 6, and an adhesive or the like is used in addition to the airtight 1. The pressure of this injected gas is desirably 1 atm, which is the same as the external pressure at room temperature. A lid 4 is then placed on the sealed upper container 1.

Normally, in the fixed magnetic disk device 10, internal pressure in the device chamber 100a increases due to internal heat generation when the motor 104 and the like are driven.
Or it is exposed to changes in internal pressure due to changes in ambient temperature outside the device. Under such conditions, when the internal pressure of the fixed magnetic disk drive 10 becomes higher than the external pressure, the pressure fluctuation absorbing plate 3 expands toward the atmosphere, that is, the opposite side from the pressure absorbing chamber 3a, and absorbs the increase in internal pressure. and relax. On the other hand, when the internal pressure of the fixed magnetic disk device 10 becomes smaller than the external pressure,
The pressure fluctuation absorbing plate 3 extends inside the fixed magnetic disk device 10, that is, toward the pressure absorbing chamber 3a side, and alleviates a drop in internal pressure.

In this way, the difference between the internal pressure of the fixed magnetic disk device 10 and the atmospheric pressure (external pressure) is minute, and only the escape of low-viscosity gas due to the concentration difference needs to be considered. To prevent the low viscosity gas from escaping due to the concentration difference, a rubber material with low permeability to the low viscosity gas is used as the packing 102, and the width of the pressure fluctuation absorbing plate 3 and the sealing part of the packing 102 (the moving distance of the low viscous gas) is adjusted. Just make it bigger.

Examples of the above-mentioned low-viscosity gas include helium gas and hydrogen gas, which is stable and has excellent cooling properties. For example, when helium gas is used, it is preferable to select and use a material with low gas permeability, such as butadiene or acrylonitrile rubber, as the material for the packing 102. For example, the gas permeability coefficient of substances for helium gas is described in ``Materials and Moisture Handbook'' (Kyoritsu Publishing), edited by the Polymer and Moisture Absorption Committee of the Society of Polymer Science and Technology, pages 370 to 377. In addition to this, an inert gas such as argon may be used as the low-viscosity gas, or a combination of the above-mentioned gases (including air) may be appropriately combined and mixed.

In this example, aluminum was used as the pressure fluctuation absorbing plate due to its light weight, but any metal member that is not permeable to low viscosity gases and has excellent resistance to repeated stress may also be used. Any sheet metal can be used.

In addition, the shape of the pressure fluctuation absorbing plate is a groove shape that is a combination of uneven shapes, but it is also possible to use a spring shape, for example, if it can be deformed in response to pressure fluctuations, and a metal that is impermeable to the internal atmospheric gas. As long as this method is used, it can be used with the same effect as the above embodiment.

〔Effect of the invention〕

As described above, 1. According to the present invention, the low-viscosity gas atmosphere, which is essential for minutely controlling the flying height of the head slider, which is a means of increasing the density of fixed magnetic disk drives, can be maintained at a stable composition for a long period of time. Since the structure is configured so that high-density recording and reproduction of information is possible, the reliability of the information does not decrease, and high reliability can always be obtained.

[Brief explanation of drawings]

Fig. 1 is a cross-sectional side view of a fixed magnetic disk device showing a schematic configuration of an embodiment of the present invention, Fig. 2 is a top view of a pressure fluctuation absorbing plate, and Fig. 3 is a conventional air-tight fixed magnetic disk drive. FIG. 1 is a schematic cross-sectional view of the device. In the figure, 1 is a whistle-sealing upper container, 2 is a hole, 3 is a pressure fluctuation absorption plate, 3b is a low-viscosity gas filling port, 6 is a sealing device, 10 is a fixed magnetic disk device, 100 is a sealed lower container, 102
103 is a fastener, 104 is a basket, 105
106 is a magnetic disk, 106 is a signal control unit, 107 is a helad arm, 108 is a flying slider, and 109 is a magnetic head. In addition, in the figures, the same reference numerals indicate the same or equivalent parts. Figure 1 throw 1: 嘗Igosha i5 container - 2:)shi3: l] Yoka 'hensujishiri9gshirimata [10:fixed j
& Viewing Te'isk device Figure 2 3b 3b: A 6, rice 8 = 1, 1 student's book seal Ro 6: village tool Figure 3 ■ 100: Mitsukei 1 subordinate p container 1o2: ノ\°・Shikin 103: Koboko 104: Motor 105: Stone j! IX, Disc 108: ：Mu-hi, Slider 109: Stone Cooking Song, 7th ζ'

Claims (6)

[Claims] (1) A device main body that records and reproduces information on the magnetic disk using a magnetic head that levitates from the magnetic disk due to the airflow generated when the magnetic disk rotates; a fixed magnetic disk device comprising a container that keeps the interior airtight, the container being filled with a low-viscosity gas that makes the flying height of the magnetic head with respect to the magnetic disk smaller than that of air; A fixed magnetic disk device characterized in that a pressure fluctuation absorbing plate is used as a part of the container, which deforms due to a pressure difference between the inside and outside of the container to eliminate the pressure difference. (2) The fixed magnetic disk device according to claim 1, wherein the low-viscosity gas contains at least one type of inert gas. (3) The fixed magnetic disk device according to claim 1 or 2, wherein the low viscosity gas contains hydrogen gas. (4) The fixed magnetic disk device according to any one of claims 1 to 3, wherein the pressure fluctuation absorbing plate has a plurality of groove shapes. (5) The fixed magnetic disk device according to any one of claims 1 to 4, wherein the pressure fluctuation absorbing plate is made of an aluminum conductive plate. (6) The pressure fluctuation absorbing plate has an externally exposed portion covered with a protective cover having at least one hole, and external pressure is introduced through the hole. The fixed magnetic disk device according to any one of Items 1 to 5.