JPS58199482A - Closed type magnetic disk device - Google Patents

Abstract

PURPOSE:To perform quick balancing with even abrupt variation in atmospheric pressure and to prevent intrusion of the dust, by balancing the pressure in a closed container with the external pressure through an expandible bag body. CONSTITUTION:A closed container 1 containing a magnetic disk device communicates with an atmospheric pressure balancing device 2 through a communicating tube 7. The container 2a of the balancing device 2 communicates with the atmospheric pressure through an outside air communication tube 8. The closed container 1 keeps pressure balance with the outside air through the bag body 13 such as bellows having a return spring 14 which expands and contracts according to the pressure in the container. Further, a filter 9 is provided in a communication hole for the communication between the inside of the bag body 13 and the outside air; this filter has large dust filtering effect even if its air resistance is large. Abrupt variation in pressure is dealt with by the expansion and contraction of the bag body 13, which returns at a low speed to its initial position by the return spring body.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a so-called sealed magnetic disk device, which is a magnetic disk device housed in a sealed container.

Generally, this type of sealed magnetic disk drive houses a magnetic disk drive including an i-disk, a magnetic head, a magnetic disk drive device, etc. in a sealed container, and is stored in a clean atmosphere that prevents dust from entering from the outside. The sealed container mentioned above not only prevents dust from entering from outside, but also has the function of maintaining an equilibrium between the air pressure inside and outside the container. I need to have it.

Therefore, changes in the pressure inside and outside the sealed container may occur □ suddenly or slowly. In the former case, changes occur when the magnetic disk begins to rotate and when it stops. In the latter case, it occurs when the temperature rises due to the heat generated by each component of the magnetic disk drive, when air expands and contracts during cooling, and when atmospheric pressure changes due to weather changes. Easy to do.

In this way, if the pressure difference between the inside of the sealed container housing the magnetic disk drive and the outside becomes large, the magnetic head may not be able to fly off the magnetic disk in a stable state when the magnetic disk rotates, or the magnetic head may Since lubricating oil is likely to enter the disk drive device, for example from the spindle, etc., in conventional sealed L-shaped magnetic disk drives of this type, a pressure balance device is installed in the closed container to balance the air pressure inside and outside. .

Such a pressure equalization device may include, for example, providing a relatively small through hole in a part of the wall of a closed container that penetrates the inside and outside.
This through hole 1 is often equipped with a filter to filter dust contained in the outside air flowing through it. However, in such a pressure balancing device, if the thickness of the filter is increased in order to increase the dust filtration effect of the filter, the air resistance passing through the filter increases significantly. If a sudden change in the air pressure occurs, it becomes impossible to follow this change and quickly bring the air pressure inside and outside the closed container into equilibrium. Therefore, in the above-mentioned conventional pressure equalization device, a thin filter with low air resistance is used to improve air circulation, making it easy for dust to enter the inside of the closed container. There are drawbacks that can cause malfunctions such as magnetic and \RAD crashes.

This invention was made with attention to this point, and when the pressure change inside and outside the sealed container housing the magnetic disk device occurs slowly, the pressure change inside and outside the sealed container. Even if a sudden occurrence of air pressure occurs, the air pressure inside and outside the sealed container can be quickly balanced by following this situation, and the airtight container is equipped with a pressure equalization device that has an excellent dust filtration effect. The purpose of this project is to provide a compact magnetic disk device.

That is, both FIGS. 1 and 2 show one embodiment of the present invention, with FIG. 1 being a front view of a sealed magnetic disk device showing a cross section of a sealed container, and FIG. 2 showing a pressure equalization device. In this diagram, (1) is a closed container, (2) is a pressure equalization device, and (3) is a spindle (4) via a belt (5).
The spindle (4) has a bearing (6) on the bottom plate of the closed container (11).
The magnetic disk Ql11 is rotatably supported through the magnetic disk Ql11 and is detachably mounted thereon.

(The force is a communication pipe that communicates the inside of the closed container (11) and the inside of the container (2a) of the pressure equalization device (21) with each other, and the inner end of this communication pipe (7) on the closed container (1) side is connected to the It extends to the vicinity of the spindle (4) and the bearing (6).(8) is connected to the container (2) of the pressure equalization device (2).
a) An outside air circulation pipe for letting outside air in and out of the interior; 03 is a magnetic/rad drive unit for moving the magnetic head 011 corresponding to the magnetic disk a to the target track; 031 is the air pressure equalization device (2); A communication pipe (7) whose one end is fixed to one side wall in the container (2a) and projects into the container (2a).
A bag body made of a bellows or the like that is expanded by the pressurized air in the sealed container +11 flowing in from the airtight container +11 and contracted by a return spring body portion to be described later, αa is the free end of this bag body a3 and the other side wall of the container (2a). A return spring body (9) is made of a metal coil spring or the like and is stretched between the bag body α3 and expands or contracts the bag body α3 to hold it for a predetermined length ζ. The filter (9) attached to the communicating hole is one that has relatively high air resistance but has an extremely good dust filtration effect.

The pressure balance device in the hermetic, closed magnetic disk device of the present invention is configured as described above, and the second section is divided into two sections: whether the magnetic disk device in the closed container (1) is stopped or not;
Alternatively, it indicates a state during steady operation. Now, when the spindle (41) of the stopped magnetic disk device starts to rotate, the air pressure in the airtight container (11, especially in the vicinity of the spindle (4) drops rapidly, but
Since the air inside 31 is rapidly sucked into the closed container +11 through the communicating pipe port, the air pressure inside and outside of this closed container (1) can be balanced.

In this way, the air inside the bag (J3) is sucked into the airtight container (1).Thus, as shown in FIG. However, when the spindle (4) of the magnetic disk drive reaches steady rotation, the bag body a3 begins to expand due to the return tension force of the return spring body, sucking outside air through the filter (9). While doing so, the vehicle returns to the state shown in the second section at low speed.

Next, when the spindle (41) of the Yamaki disk device, which had been rotating steadily, begins to stop, the air pressure in the sealed container m, especially near the spindle (4), rises rapidly, but the pressurized air is transferred to the communication pipe ( 7) into the bag body 03), and the bag body Q31 is further expanded from the state shown in Figure 2), as shown in FIG. can be done. And the spindle (41
When the bag body OJ completely stops, the bag body OJ changes from the state shown in FIG. 2 10I to the second
It returns to the state shown in the figure at low speed.

The above explanation is based on the sealed □ container containing the magnetic disk device +
This explains the operation when a sudden change in the pressure inside and outside of 11 occurs. Since outside air is sucked in or discharged through the filter (9) at a low speed, there is no problem even if the air resistance of the filter (9) is large in order to increase the dust filtration effect.

As mentioned above, the sealed magnetic disk device of the present invention has the following features:
Not only when the pressure change inside and outside the sealed container that houses the magnetic disk drive occurs slowly, but also when the pressure change inside and outside the sealed container suddenly changes, the pressure inside and outside the sealed container is adjusted accordingly. Not only can it follow this and achieve rapid equilibrium, but it also has an excellent dust filtration effect.
This makes it possible to prevent the occurrence of pressure differences between the inside and outside of the sealed container and the occurrence of various failures due to the infiltration of dust, thereby significantly contributing to improving the reliability of sealed magnetic disk drives.

In the above-mentioned embodiment, a problem was described in which a bellows was used as the bag body 03, but a similar effect can be obtained by using something like a bag-like diaphragm that expands and contracts. As for the spring body u41, we have described the case where a metal coil spring is used, but the bag body (+3
It goes without saying that the same effect can be obtained even if the bag body OJ is made to have an elastic force and the bag body OJ is expanded by its own restoring force.

[Brief explanation of the drawing]

Each of the figures shows an embodiment of the present invention; Fig. 1 is a front view of a sealed magnetic disk device showing a section of the sealed container, and Fig. 2 is a section diagram illustrating the operation of the pressure equalization device. be. In the drawing, (1) is a closed container, (2j is a pressure balance device, (
2a) is a container, (3) is a drive motor, (4) is a spindle, (7) is a communication tube, (8) is an outside air distribution tube, (9) is a filter, OQ is a magnetic disk, all is a magnetic head, (
12 is a magnetic/rad drive device, 03 is a bag body, and a41 is a return spring body. Note that the same reference numerals in the figures indicate the same parts. Agent Shin Kuzuno - Figure 1 Sat

Claims (1)

[Scope of Claims] An airtight container housing a magnetic disk device inside the il+ and a bag telescopically housed in a container that communicates with outside air are communicated with each other via a communication pipe, and the airtight container When the air pressure inside the airtight container decreases, the air inside the bag is rapidly sucked into the airtight container to balance the air pressure inside and outside the airtight container, and when the air pressure inside and outside the airtight container is balanced, the bag is expanded. A sealed magnetic disk device characterized in that outside air is sucked into the bag through a filter. (2) The sealed magnetic disk device according to claim 1, characterized in that a telescopic bellows is used as the bag. (31) The sealed magnetic disk device according to claim 1, wherein a return spring body such as a metal coil spring is used to extend the bag body.