JPH0192988A - Disk device - Google Patents

Abstract

PURPOSE:To keep low moisture for a long time without incurring a large sized device or increase in number of replacement of a moisture absorbing agent by providing the 1st moisture absorbing vessel formed by storing a moisture absorbing agent having a high moisture absorbing rate into a vessel having vent holes and the 2nd moisture absorbing vessel formed by storing a moisture absorbing agent whose moisture absorbing rate is not decreased into the similar vessel. CONSTITUTION:A spindle 3 supporting a disk 2 turnably, a head and its positioning mechanism are fitted to a base 1 and they are enclosed in the inside of a medium package 5 comprising the base 1 and a cover 4. The vent hole 6 is provided with the 1st moisture absorbing agent vessel 9 absorbing moisture invaded externally from outer air via a throttle 8 and the moisture absorbing agent 13 having a high moisture absorbing rate at a high moisture is stored therein. The vent hole 7 connects to the 2nd moisture absorbing vessel 15 to absorb the moisture in the inside of the medium vessel 5 through the throttle 14 and a moisture absorbing agent 17 whose moisture absorbing rate is not decreased at a low moisture is stored therein. Thus, a low moisture is maintained for a long time with a small amount of moisture absorbing agent without incurring a large sized device or increase in the number of replacement of the moisture absorbing agent.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a disk device, and more particularly to a structure suitable for keeping the humidity in a container housing a disk and a head low for a long period of time.

[Conventional technology]

In recent years, in order to obtain a larger storage capacity, disk devices have increasingly adopted continuous thin film media using the plating or sputtering method, which can increase the recording density per area. There are various types of magnetic materials that can be used as thin film media, but when a metal element such as Th''l CrlNi is used as a medium, corrosion of these materials poses a major problem in terms of information preservation. It is known that the presence of moisture has a large effect on the corrosion of metal materials.
To keep the media in perfect condition without corrosion for a long time.

It is necessary to store the medium in a sealed container and to keep the humidity inside the container as low as possible regardless of the environment around the device.

On the other hand, a light-loaded head with a small load is used to press against the disk surface, and when the disk is stopped, the head stops in contact with the disk surface, and when the disk rotates, the head starts floating. C8S
) type disk device, the head and disk are in close contact with each other while the disk is stopped.

In this situation, the support spring of the head may be damaged by the tangential force applied to the head when the disk starts rotating, or the disk surface may be damaged by the reaction of the support spring when the head is forcibly pulled away from the disk surface. Adsorption phenomena may occur. The ease with which this adsorption phenomenon occurs depends largely on the surface roughness of the disk surface and the surrounding humidity; the higher the humidity, the higher the humidity.

Also, if the surface roughness is small, adsorption becomes easier regardless of whether the medium is a conventional coating type or a continuous thin film medium. Therefore, in order to prevent this adsorption phenomenon, it is desirable that the humidity inside the container be low.

In view of the above, the conventional device is
As described in Japanese Patent Application No. 57170, the media container is provided with a constriction that communicates with the outside air, and a moisture absorbent is placed in the container that is connected to the media container through the constriction, thereby limiting the amount of moisture that enters the container from the outside air. The moisture inside the container is absorbed by a moisture absorbent to keep the inside of the container at low humidity for a long period of time. Or as described in Japanese Patent Application Laid-Open No. 60-147984,
A ventilation hole is provided inside the media container that connects with the outside air through a moisture absorbent.

Moisture intrusion from the outside air is restricted and air made low in humidity by a moisture absorbent is allowed to flow into the container.

[Problem that the invention seeks to solve]

In the above conventional technology, in order to make the moisture absorbent work and keep the inside of the container at low humidity for a long period of time, a restriction is provided in the breathing hole between the outside air and the moisture absorbent container and the medium container. A restriction is provided to limit the amount of moisture passing through each person. However, no consideration is given to the characteristics of the amount of water absorbed by the moisture absorbent relative to the relative humidity of the surroundings, and in order to maintain low humidity for a long period of time, the amount of moisture absorbent required is large. It is necessary to increase υ
In order to avoid increasing the size and the number of replacements, the humidity inside the container must be set to a certain level.

An object of the present invention is to provide a disk device that can maintain low humidity for a long period of time without increasing the size of the device or increasing the number of times the desiccant is replaced.

c. Means for deciding the problem] The above purpose is to use two types of moisture absorbing agents, such as silica gel, which have different characteristics of water absorption with respect to the surrounding relative humidity. Select a material (Type B for silica gel) and a material whose water absorption rate does not decrease even in an environment with low relative humidity (Am for silica gel), and use the former as a moisture absorbent for moisture that enters into the recording medium container from the outside air. The first moisture absorbent container is connected with a ventilation hole each having a restriction, and the latter is connected to the medium container by a ventilation hole having a restriction. This is achieved by storing the moisture absorbent in the second container.

[Effect]

A moisture absorbent contained in the moisture absorbent container between the outside air and the media container absorbs moisture that enters the media container with the atmosphere flowing through the breathing hole or by diffusion. Here, the moisture absorbent is selected from a type that has a high water absorption rate at high relative humidity, as shown by the water absorption characteristics as B in Figure 2. It acts strongly when the humidity is high. And since it has a high water absorption rate, this is combined with the fact that we have installed a restriction in the ventilation hole of the container.

The moisture absorbing effect can be maintained for a long period of time without using a large amount of moisture absorbent in a high humidity environment.

On the other hand, the moisture absorbent stored in a container connected only to the media container does not have a low water absorption rate even in an environment with low relative humidity, as shown by A in Figure 2. It also absorbs moisture and keeps the relative humidity inside the container low. The moisture inside the medium container that enters from the outside air is reduced to a relative humidity of about 50 degrees or less by the first moisture absorbent, and between the first moisture absorbent container and the medium container and between the medium container and the second moisture absorbent. A constriction provided in the vent hole between the second moisture absorbent container controls the moisture that enters the second moisture absorbent container by diffusion, so that a large amount of moisture absorbent is transferred to the second moisture absorbent container. Even if you don't use it! The relative humidity inside the body container can be kept low for a long period of time.

〔Example〕

An embodiment of the present invention will be described below with reference to FIG. In the figure, a spindle 3 that rotatably supports a disk 2, a head, and its positioning mechanism (not shown) are attached to a base 1.

They are sealed inside a media container 5 consisting of a base 1 and a cover 4. The base 1 is provided with ventilation holes 6°7. A first moisture absorbent container 9 for absorbing moisture entering from the outside air is connected to the ventilation hole 6 through a diaphragm 8t. The moisture absorbent container 9 is placed in contact with the outside air through the aperture 10 on the opposite side of the base 10.

A filter 11, 12 is provided inside the aperture, and a moisture absorbent 13, which has a high water absorption rate at high humidity, is placed between them. A second moisture absorbent container 15 for absorbing moisture inside the medium container 5 is connected to the ventilation hole 7 via a diaphragm 14 , and a filter 16 . Furthermore, a moisture absorbing agent 17 whose water absorption rate does not decrease even when the internal pressure of the filter 16 is low and humidity is stored.

Expansion and contraction of the air inside the container due to temperature changes in the medium container 5 and
Container associated with device operations such as starting and stopping the disc.

Due to internal pressure fluctuations, outside air flows through the restriction 10 through the first moisture absorbent container 9 and into the medium container 5 .

(Hereinafter referred to as breathing action.) At this time, the dust in the outside air is removed by the filter 12, and the dust generated from the moisture absorbent 13 is further removed by the filter 11.

The inside of the medium container 5 is kept clean. If the relative humidity of the outside air is high, the moisture that enters into the medium container 5 due to the above-mentioned breathing effect or the diffusion effect through the aperture 10.8 is absorbed by the moisture absorbent 13 and is therefore absorbed by the medium through the moisture absorbent container 9. The relative humidity of the air flowing into the container 5 has decreased to approximately 50% or less. Moisture absorbent 1 stored in second moisture absorbent container 15
Since the water absorption rate of No. 7 does not decrease at low humidity, the inside of the desiccant container 15 is maintained at a relative humidity of almost 0 degrees, and the
By appropriately selecting the dimensions of 4, the relative humidity within the media container 5 can be maintained at a desired value between 0 and 3 Gfi.

Moreover, the amount of moisture passing through the aperture 8 is suppressed to a very small amount by the action of the moisture absorbent 13 in the first moisture absorbent container, so even if the amount of moisture absorbent 17 is not large, it remains in the moisture absorbent container 15 for a long period of time.
Can maintain low humidity inside. The filter 16 removes dust from the moisture absorbent 17 to prevent it from entering the inside of the medium container 5, thereby maintaining the cleanliness inside the medium container.

〔Effect of the invention〕

As described above, according to the present invention, the moisture inside the medium container of a closed disk device is provided between the outside air and the medium container and by being directly connected to the medium container. Two types of hygroscopic agents with different water absorption characteristics stored in two hygroscopic containers can adapt to and absorb the surrounding relative humidity, so a small amount of hygroscopic agent can reduce the size of the equipment and the number of times the hygroscopic agent must be replaced. The effect is that low humidity can be maintained for a long period of time without causing an increase in humidity.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view of an embodiment of the present invention, and FIG. 2 is an explanatory diagram showing an example of the water absorption rate of a moisture absorbent used in the present invention. 5...medium container, 8. jD...Shibaku S9...1st
moisture absorbent container, 13... moisture absorbent, 14... squeeze bottle, 1
5... Second moisture absorbent container, 17... Moisture absorbent.

Claims (1)

[Claims] 1. In a disk device consisting of a disk and head for recording and reproducing information, and a media container that seals off the mechanical part including the disk and head from the outside air, it has a high water absorption rate and absorbs a large amount of water in a high humidity environment. A first moisture absorber in which a moisture absorbent capable of adsorption is housed in a container having a vent connected to the outside air on one side and the medium container on the other side through a diaphragm, and the water absorption rate does not decrease even in a low humidity environment. and a second moisture absorber in which a moisture absorbent is housed in a container having a ventilation hole connected to the inside of the medium container through a diaphragm.