JPS5928281A - Magnetic disk device - Google Patents

Abstract

PURPOSE:To realize a miniature structure and a low cost and at the same time to reduce oscillation and noise for a magnetic disk device, by providing an open air path between the inside of the disk device and the open air and at the same time attaching an air filter at an edge of an airway at a part where a gap is minimum. CONSTITUTION:A rotor 4 has eccentricity to a non-rotary part 5, and therefore P1>P2 is satisfied between pressures P1 and P2 at the gap of the rotor 4 and the part 5. While P2<P3<P1 is obtained for the pressure P3 at the part where the airways 6 and 7 are opened by varying the distance l of eccentricity. In other words, the open air flows into a magnetic disk device through an open air path 7. In this case, the dust, etc. are got rid of by the function of an air filter 8 attached at an edge of the path 7. Thus the extremely clear air is supplied into the disk device. It is needed to flow the air equal to the inflow quantity to outside. For this purpose, the airway 6 is effective. The air generated inside the disk device and including dust, etc. is discharged outside the disk device via the airway 6.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a magnetic disk device, and particularly to a magnetic disk device that can maintain air cleanliness inside the magnetic disk device.

In general, a magnetic disk drive is a device that reads and writes magnetic records by floating a magnetic head through a small gap by air that circulates around a magnetic disk that rotates at high speed.

The history of the development of magnetic disk devices is rooted in improving recording density and reducing costs, and preventing so-called head crashes from occurring is especially important for increasing reliability. It is a matter of great interest.

Head clarity means that a magnetic head collides with a magnetic disk due to dust floating in the air, and as a result, it becomes impossible to read or write magnetic recording. Therefore, the air inside the device must be kept clean at all times, and various efforts have been made for this purpose.

Most conventional magnetic disk drives use an airful one-way system to clean the air inside the magnetic disk drive, in which clean air is forcibly fed in from the outside using a near blower, etc., and its purpose is to clean the inside of the drive, especially the disks. The goal was to create positive pressure around the rotating mechanism relative to the outside air.

In other words, in general, the area around the disk rotation mechanism tends to have a negative pressure with respect to the outside air, and if grease is removed from the bearings of the disk rotation mechanism, this will lead to dust entering from the outside air, making it difficult to clean the air inside the device. I can't imagine it (・.

For this reason, conventional magnetic disk devices are equipped with a blower or the like outside the device as a means for forcibly feeding clean air from outside.

However, such a magnetic disk device has the disadvantage of increasing the size of the device and causing vibration and noise problems when blowing air.

SUMMARY OF THE INVENTION An object of the present invention is to provide a magnetic disk device that can be made smaller and cheaper, and can reduce vibration and noise.

That is, an object of the present invention is to eliminate the above-mentioned drawbacks of the conventional example, to provide a magnetic disk device that promotes miniaturization and cost reduction of the device, and can also strongly reduce vibration and noise problems. There is a particular thing.

The magnetic disk device of the present invention includes a magnetic disk that rotates integrally with a shaft, a rotating body that rotates integrally with the shaft and the magnetic disk, and an airtight cover that accommodates the magnetic disk in cooperation with a cover. The interior of the magnetic disk drive is comprised of a cylindrical cavity eccentric to the rotary body, and a cylindrical cavity is provided on the side with a smaller gap between the rotor and the rotor in order to ventilate the cavity and the inside of the magnetic disk drive. a non-rotating part in which a second air passage is provided on a larger side of the first air passage, and the incoming air supplied from the hollow part through the first air passage is cleaned and supplied to the inside of the magnetic disk device. It is configured to include an air filter for

That is, in the magnetic disk device of the present invention, on the side where the magnetic disk rotation mechanism section is exposed to the outside air, the non-rotating portion surrounding the rotating body has an elliptical shape that is eccentric with respect to the center of the rotating body, In addition, in the non-rotating part where the gap between the rotating body and the non-rotating part is the maximum and the minimum, a ventilation passage connecting the inside of the magnetic disk device and the outside air exists, and the gap is the minimum. The ventilation path of the section is configured with an air filter interposed at one end.

Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a cross-sectional view of a magnetic disk drive showing one embodiment of the present invention, and in particular, it is also a structural view schematically showing the corpse of a rotating mechanism section.

A cover 3 covers the magnetic heads 2 arranged on the surface of the magnetic disk 1, and isolates the inside of the magnetic disk device from the outside air. The mechanism for rotating the magnetic disk 1 usually includes a disk mounting section and a shaft 8. There is a rotating part composed of parts called a shaft part including a bearing 9, a rotor part, a pulley part, etc., and the shaft 8 is provided with a rotating body 4 that rotates integrally with the magnetic disk 1.

Furthermore, although the base plate mainly occupies that position, the non-rotating portion 5 forms the outer contour of the rotating body 4 exposed to the outside of the magnetic disk device.

FIG. 2 is a bottom view of the magnetic disk drive shown in FIG. 1 viewed from below, and the center O' of the non-rotating part 5 is offset by a distance of 2 from the center 0 of the rotating body 4. represents. Furthermore, the ventilation path 6 through which the inside of the magnetic disk drive and the outside air communicate is located at the longest point of the gap in the cylindrical cavity 10 formed in the radial direction between the rotating body 4 and the non-rotating section 5, and similarly, the shortest point A ventilation passage 7 is provided. In addition, air passage 7
An air filter 8 is interposed at one end.

Based on the above structure, when the rotating body 4 rotates, air flows in the direction of the arrow shown in the figure. This air flow will be explained in detail below.

Since the rotating body 4 and the non-rotating part 5 are eccentric, the pressure P in the gap between the two is P 1 > P
A relationship t arises. In other words, a wider gap will produce a lower pressure.

On the other hand, the pressure P at the part where the ventilation passage 6-6.7 opens inside the magnetic case holder can be changed to *Pt<Pa<P by changing the eccentric distance 1.

relationship can be obtained. The air flow will then follow the arrows in the figure. That is, outside air flows into the magnetic disk drive through the ventilation path 7. At this time, the air filter 8 interposed at one end of the ventilation path 7 acts to trap dust and other particles, so extremely clean air flows into the magnetic disk drive. This will flow into the inside of the device. As for the flow of air, it is necessary to flow the air out to the outside by the amount that flows in, and for this purpose, the ventilation path 6 becomes effective. Air including dust generated inside the device flows out from the ventilation path 6 to the outside of the device.

To put it simply, these operations utilize the pressure difference created by the action of an eccentric pump outside the device, and function equivalent to the forced air circulation effect from the outside using a blower, etc. found in conventional magnetic disk drives. It can be said that it has the following.

In addition to the operational effects described above, the advantage of the present invention is that it requires only a very simple design change, that is, a change in the position of the circular portion of the non-rotating portion 5. Of course, the circular shape of the non-rotating portion 5 is not limited to the base plate, but it is clear that the same effect can be obtained by using a cylindrical shape made of silver or gold, or an elliptical shape instead of an eccentric circle.

By providing a rotating body in place of an air blower, the magnetic disk device of the present invention can circulate the inside of the magnetic disk device while rotating integrally with the magnetic disk, making it possible to reduce the size and cost as well as reduce vibration and noise. It has the effect of reducing the

In other words, the magnetic disk device of the present invention has a structure that creates an air flow that allows clean air to flow in from outside the device and dust generated from the disk rotation mechanism etc. to flow out to the outside air, so that the air inside the device can be kept clean. This has the effect of avoiding accidents such as head crashes and increasing the reliability of the magnetic disk device.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing one embodiment of the present invention, and FIG.
FIG. 3 is a bottom view of the embodiment shown in the figure. DESCRIPTION OF SYMBOLS 1... Magnetic disk, 2... Magnetic head, 3... Cover, 4... Rotating body, 5...
・・・Non-rotating part, 6... Ventilation path, 7...
・Vent passage, 8... Air filter, 8...
・Shaft, 9... Group ・Bearing, 10...
Cavity, Pl, P2. P...Pressure!・Old・
・Eccentricity distance. 9 - Figure 1 Figure 2

Claims (1)

[Claims] A magnetic disk that rotates integrally with a shaft, a rotating body that rotates integrally with the shaft and the magnetic disk, and a cover cooperate to configure an airtight inside of the magnetic disk device that accommodates the magnetic disk. A cylindrical cavity is eccentric with respect to the rotating body, and the first ventilation passage is arranged on the side with a smaller gap to the rotating body and on the larger side in order to ventilate the cavity and the inside of the magnetic disk device. a non-rotating part provided with a second air passage; and an air filter for cleaning incoming air supplied from the cavity through the first air passage and supplying the purified air to the inside of the magnetic disk device. A magnetic disk device characterized by: