JPS60133578A - Storage device of magnetic disc - Google Patents

Abstract

PURPOSE:To reduce the titled device at its size and cost and to collect foreign particles in a case completely and rapidly by setting up a conical dust filtering mechanism, arranging its outer periphery side adjacently to a magnetic disc and sealing its inner periphery side with cover. CONSTITUTION:The conical dust filtering mechanism 41 is constituted of a conical member 44 having an air inflow hole 43, a filter 42, etc. and fixed to the cover 18 of a sealing body 13. The outer periphery side is arranged close to the surface of the magnetic disc 11 so that the foreign particles do not flow backward and air containing foreign materials passes through the filter 42 completely, and the inner periphery side is sealed tightly with the cover 18 so that dust does not flow into the inner periphery side. In said constitution, the air passed from the outer periphery through the filter 42 passes through the disc 11 to form a self circulation air system. Consequently, the device can be reduced at its size and cost and the foreign particles in the sealing body can be collected completely and rapidly.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a magnetic disk storage device having a foreign particle filtering mechanism, and in particular to a conical disk storage device that efficiently removes foreign particles inside a self-circulating magnetic disk storage device. The present invention relates to a magnetic disk storage device having a shaped foreign particle filtering mechanism.

[Background of the invention]

In recent years, small magnetic disk storage devices using 8-inch, 5-inch, and 3-inch diameter magnetic disks have become popular as storage devices for small-scale computers. This kind of magnetic disk storage device has the same physical and electrical interface as a floppy disk device, so it is possible to design and develop a high-density, large-capacity magnetic disk storage device that is extremely miniaturized and compact. It must be. Such miniaturized high-density, large-capacity magnetic disk storage devices are technically more difficult than large-sized magnetic disk storage devices. Under these circumstances, 5-inch magnetic disk storage devices with small capacity and relatively slow access times have entered the market. The demand for compact, energy-saving equipment is becoming increasingly strong, and each company is cutting back on its development.

Encapsulating body of a head disk assembly of a magnetic disk storage device using a hard magnetic disk (hereinafter referred to as T-(D)
(referred to as A) must be clean. Further, foreign particles must not be generated inside the HDA or foreign particles must not enter from the outside. This is because the magnetic disk surface and the magnetic head surface are floating due to the air bearing effect that maintains a flying height of 0.5 μm, and in this way, the magnetic disk surface and the magnetic head surface, which are rotating at high speed in close proximity t7. If foreign particles are present between the two, the magnetic disk surface will be damaged, making it impossible to read or write information to the magnetic disk surface through the magnetic head. For this purpose HDA
Normally, the parts stored inside the chamber are subjected to ultrasonic washing and cleaning, and all assembled parts are assembled in a very clean atmosphere in a dust-proof room. A certain amount of foreign particles are present even in a device that has been assembled, and this significantly impairs the reliability of the device, so it is necessary to remove even a very small amount of foreign particles. The conventional dust filtration mechanism of this type of magnetic disk storage device is mainly based on a self-circulating air system. This self-circulating air system circulates air (bumping effect) using the pressure difference between the inner and outer circumferences of the magnetic disk rotating at high speed within the HDA. One type of dust filtering mechanism is a method in which a flat dust filtering mechanism is provided above the magnetic disk assembly to purify the air inside the HDA sealed body. Such a mechanism is used, for example, in
° as described in Publication No. 9349.

In this method, since the filtration mechanism has a flat plate structure, the filtration efficiency (completely and quickly removing foreign particles) is poor, and it is difficult to quickly clean the inside.

That is, it is difficult to increase the internal circulation efficiency and circulate to the filtration mechanism as quickly as possible to completely remove it. In addition, since the magnetic disk is a flat plate, if a certain amount of space is not left between the upper disk surface and the lower surface of the filtration mechanism, the high-speed rotation of the magnetic disk will cause a lot of wind damage, which will cause internal heat generation. Further, such an opening prevents foreign particles from passing through the dust filtering mechanism.

There is a drawback that foreign particles flow backward between the upper disk surface and the lower surface of the filtration mechanism, reducing filtration efficiency. Another method is to provide a cube-shaped dust filtering mechanism within the HDA enclosure to purify the air within the enclosure.

In this method, the filtration mechanism has a cubic structure (prismatic or cylindrical, etc.), so it is not possible to increase the planar area. For this reason, since the filtering mechanism is formed by folding several layers of filter media, the filtering mechanism itself becomes large. In a small magnetic disk storage device with a diameter of 5 inches or 3 inches, the volume inside the sealing body is very small, so it is difficult to accommodate the filtration mechanism bent into several layers in this small sealing body. It is very difficult due to the relationship. In addition, if we try to reduce the number of folded layers of the filter material and make the shape compact so that such a filtration mechanism can be accommodated in a 5-inch diameter or a sealed body of a 5-inch diameter magnetic disk storage device, the dust filtration mechanism must be able to maintain an appropriate air volume. When the particles pass through, the resistance becomes large, resulting in a large pressure loss, resulting in poor internal circulation efficiency and foreign particle complement efficiency, making it impossible to achieve the original purpose of the magnetic disk storage device.

In addition, in devices with a cubic dust filtering mechanism, the casing forming the cubic dust filtering mechanism and the end surfaces of the four materials (the surfaces in contact with the casing), which have a folded structure, are completely sealed with an adhesive around the edges. must be completely sealed. Furthermore, when adhering, it is very difficult and requires a lot of man-hours because the end faces are not flat. For this reason, the filtration mechanism itself becomes very expensive, making it unsuitable for use with 8-inch, 5-inch, or 3-inch diameter magnetic disk drives because they must be manufactured at a very low cost.

Next, regarding the drawbacks of the air circulation system of conventional equipment, dc! I will post it. It is necessary to completely circulate the air inside the HD A in order to remove foreign particles within the confining body and to maintain a constant temperature within the confining body. This circulation method is limited by the height of the device itself (to ensure compatibility with floppy disk devices), and a method is adopted in which the material is circulated on the base side of the confining body located at the bottom of the device. In this method, air flows in from the bottom of the hub attached to the spindle shaft, multiple through holes are provided on the side of the hub, and multiple through holes are provided in the multiple disc spacers to draw the internal air. The main thing is what circulates.

However, with this method, there is a very negative pressure between the outer diameter of the spindle housing and the hub, so the high speed rotation of the spin bearing causes oiliness in the base oil of the bearing grease or foreign particles from the outside to enter the HDA sealing body. It would be redundant to be exiled.

Therefore, in these methods, as a means to prevent this drawback,
Expensive ferrofluid seals are used instead of labyrinth sealing mechanisms. The disadvantage of using this magnetic fluid seal is that the rotating seal part forms a magnetic circuit between the spindle shaft and the spindle housing, and the magnetic fluid seals the seal, but the number of parts required to form the magnetic circuit is large. This increases the number of steps required and the number of man-hours required. This results in a very expensive device. Furthermore, when the magnetic fluid is flowed into the magnetic circuit section, it is very difficult to flow the magnetic fluid into the magnetic circuit because there is only a very small space, and if the appropriate amount is not injected, the magnetic fluid will leak and scatter during rotation. Since this magnetic fluid contains magnetic powder in the oil, evaporation and scattering of the base oil occur. Therefore, when used for a long time, the magnetic fluid sealing effect decreases and the sealing effect is no longer achieved.

Unless a sealing mechanism such as a labyrinth is added to prevent this evaporation and scattering, the reliability of the sealed body will be significantly impaired, and it will also become very expensive.

Furthermore, since the magnetic fluid seal is in contact with the spindle shaft through magnetic fluid, variations in viscous torque occur, resulting in variations in motor rise and fall times, and uneven rotation due to temperature changes.

Further, since a plurality of through holes are provided on the side surface of the hub, there are drawbacks such as a decrease in hub rigidity and a cause of servo head vibration. As mentioned above, conventional devices have various drawbacks.

[Purpose of the invention]

A first object of the present invention is to provide a magnetic disk storage device having a conical dust filtration mechanism that can quickly and completely collect foreign particles within the sealing body of a head disk assembly.

A second object of the present invention is to store a storage tr
It is an object of the present invention to provide a magnetic disk storage device having a dust d1 detection mechanism which is small and has a flat conical shape so as to be highly functional.

A third object of the present invention is to provide a magnetic disk storage device that improves the air circulation system within the sealed body and has a dust filtering mechanism at an optimal position to improve filtering efficiency. be.

A fourth object of the present invention is to provide a magnetic disk storage device which improves the labyrinth sealing mechanism within the sealing body and prevents foreign particles from completely entering the sealing body.

A fifth object of the present invention is to provide a magnetic disk storage device that has a small and simple shape, has a small number of parts, is inexpensive, and has a highly reliable dust filtering mechanism and air circulation system. .

A sixth object of the present invention is to provide a highly reliable, compact, large-capacity, inexpensive magnetic disk storage device that is compatible with floppy disk devices.

[Summary of the invention]

In order to achieve these objects, the magnetic disk storage device according to the present invention improves the air circulation system and labyrinth sealing mechanism within the sealing body of the head disk assembly, and has a novel conical dust filtration mechanism. .

The conical dust filtration mechanism is composed of a member having a flat conical shape, a flat plate of a donut-shaped filter P material, and a sealing member, and is close to the magnetic disk surface at a distance from the outside of the magnetic disk to the inner periphery of the magnetic disk. The first feature is that the magnetic disk is configured to be separated from the surface of the magnetic disk at the side. A second feature of the present mechanism is that the flat conical member is provided with an air inlet hole, and the conical member is configured to have a head access hole. Furthermore, this organization
A fifth feature is that the conical member is configured to have a backflow prevention vertical part around the head access hole. A fourth feature of the present mechanism is that it is disposed at a central position facing the upper magnetic disk of the magnetic disk assembly.

Furthermore, a fifth feature of the present magnetic disk storage device is that the cylindrical spindle housing, which is the first member of the spindle housing, and the hub constitute a labyrinth sealing mechanism with simple irregularities. Furthermore, this device includes a disk spacer, a guide section for the hub surface, a magnetic disk, and a hub shape that allows air to flow from the top of the hub fixed to the top of the spindle, and a magnetic disk. The sixth feature is that the device is configured such that an appropriate circulating air volume can be obtained by the fixing disk clamp.

, [Embodiment of the Invention] Hereinafter, an embodiment of a magnetic disk drive having a dust filtering mechanism according to the present invention will be described in detail with reference to the drawings.

In the magnetic disk storage device according to this embodiment, as shown in FIGS. 1 and 2, a magnetic disk assembly 1 is fixedly attached to a rotation drive section 2. As shown in FIGS. The rotation drive section 2 is constructed by integrally forming a magnetic disk drive motor 3 and a spindle section 4.

In addition, a pair of ultra-precision bearings 6,
7 supports the spindle shaft 5 above and below, and the bearing 6
, 7 in the radial and axial directions, suppressing vibration of the spindle shaft 5, and increasing the rigidity of the bearings 6.7, an appropriate preload is applied by a spring 8. The spindle housing 9 includes an iron-based cylindrical spindle housing 10 which is a first member.
It has an integral structure in which the aluminum alloy part 101, which is the second member, is cast simultaneously (or may be joined by shrink fitting).

This housing 9 is fixed to a base 10 with a plurality of screws. In order to fix the plurality of magnetic disks 11 to the rotary drive section 2 configured as described above, a hub 12 is fastened to the upper part of the spindle shaft 5 by shrink fitting or the like. In order to prevent the oily base oil of the bearing grease from scattering due to the high speed rotation of the bearings 6 and 7, the grease material is selected for the part with the hub 12, and wild range grease with low oily base oil is used. At the same time, a thermal contact labyrinth 200 (a sealing mechanism formed by a combination of concavities and convexities with a small gap between the inner and outer diameter parts of the upper part of the cylindrical spindle housing 100, which is the first member of the spindle housing, and the hub 12) is provided, and the head disk assembly is The structure is such that oil does not flow into the sealing body 15.

This labyrinth structure 200 has a spindle housing 9
Increasing the machining accuracy of the inner and outer diameters of the upper part of the first member 100, and further increasing the machining accuracy of the corresponding hub 12, making the labyrinth gap 14 as small as possible to improve the sealing effect, and further reducing the labyrinth resistance. In order to increase the length of the labyrinth gap 14 as much as possible, the part forming the labyrinth gap 14 should be as long as possible and the oily pool 15 should be 1! ! ! Several units are designed to maximize the sealing effect. In addition, the labyrinth structure 200 has been simplified and designed with machinability in mind, making it extremely inexpensive and at the same time making it possible to improve the labyrinth resistance by approximately 1.5 times compared to conventional methods. became. In addition, as an internal air circulation method to remove foreign particles in the sealing body 15 of the head disk assembly and to keep the temperature in the sealing body 13 constant, circulation is performed on the cover 18 side opposite to the base 1°. I try to do that. In this method, since air is not caused to flow from the lower part of the hub 12, it is possible to provide an inexpensive and economical device without the various technical harms mentioned above.

As this means, a plurality of magnetic disks 1 are mounted on the hub 12.
1 and a plurality of disk spacers 16 positioning guide part 1
9, and these guide parts 19 have a convex shape and function as an impeller to obtain an appropriate circulating air volume.
A gate-shaped inclined portion 20 corresponding to the flow rate of air is provided at a position between the positioning guide portions 19 on the surface of the knob 12, and this inclination is not open at the upper part of the magnetic disk assembly 1 since the suction air flow is large. The lower part has a large part area, and the lower part has a slope to reduce the opening area for the suction air volume rate, and has a wall thickness and a rib ++g shape that does not reduce hub rigidity, and furthermore, it passes through such an inclined part 20 and is properly A plurality of through holes 17 are provided in the plurality of disk spacers 16 so that the air volume can be circulated.
and a disk clamp 2 for positioning and fixing the magnetic disk 11 and disk spacer 16.
1 is also provided with a plurality of holes 22. For this reason hub 1
Since circulation is possible without providing a through hole for circulation in the hub 12, the rigidity of the hub 12 is not reduced.

Moreover, since air circulation does not occur between the outer diameter of the spindle housing 9 and the hub 12, the spindle portion (bearing side) does not become under negative pressure. Therefore, the labyrinth structure 200
Thus, it is possible to completely prevent internal contamination of the bearings 6 and 7 due to oily scattering of the grease base oil and to prevent external foreign particles from entering the sealing body 15 through the spindle portion 4. It is clear that such a configuration facilitates self-circulation of air from above due to rotation of the magnetic disk assembly 1 within the encapsulant 13.

In order to make the base 10 highly rigid, the end face of the base is raised as shown in the figure, and a gasket 39 is attached to the concave groove portion of the raised portion to form a sealing member. The reason why it is placed in the fourth section is to allow the packing 59 to be deflected to an amount that does not cause permanent deformation (deflection of about 20 to 50% of the packing thickness).

A cover 18 is fixed on the base 10 via the packing 39 to form a sealing body 13. Furthermore, a breathing filter 40 is installed in the center of the spindle part 4 of the cover 18 to prevent external dust from flowing out from the spindle part 4 due to changes in the volume of air inside the sealing body 13 due to changes in temperature or pressure. The breathing filter d0 in parentheses is directed to the airflow pressure loss of the spindle section 4 (
resistance).

If this is not done, external dust and the like will flow into the seal 13 through a gap in the bearing section of the spindle section 4.

In order to quickly and completely collect foreign particles within the sealing body 13 configured as described above, the novel conical dust filtering mechanism 4 of the present invention is used.
1 is fixed to the cover 18. This conical dust filtration mechanism 41 is mounted so that its center is located at the center of the spindle part 4 and can be used in conjunction with the air circulation system, so that it can be attached to the uppermost magnetic disk 11 of the magnetic disk assembly 1 and the cover. Due to the necessity of storing the magnetic disk 11 in a very narrow space with the magnetic disk 18 to increase filtration efficiency, the outer peripheral side of the magnetic disk 11 is designed to prevent foreign particles from flowing back and to allow air containing foreign particles to completely pass through the filter section 42. The inner circumferential side of the magnetic disk 11, which is located close to the surface of the magnetic disk 11, has a conical shape and is sealed with a cover 18 via a sealing gasket 47 to prevent dust from being carried away. By adopting such a configuration, the area of the r material of the filter 42 can be maximized in a plane, so that pressure loss is reduced and air circulation is facilitated. This conical filtration mechanism 41 is composed of a conical member 44 having a plurality of air inflow holes 43 and a filter 42.
The periphery of 2 is adhesively fixed with an adhesive. Since this is bonded in a flat shape, the bonding work is easy, and since the air flow hole 43 of the conical member 44 can be made large, there is little pressure loss, and the shape can be easily created by drawing and can be made flat. A high-performance dust filtration mechanism that can be stored in a narrow space at a very low cost can be obtained. Also, inside the sealing body 13, a plurality of magnetic heads 23 are installed at desired track addresses on the surface of each magnetic disk 11, which is a recording medium of the magnetic disk assembly 1.
It has a high-speed access positioning mechanism 24 for stably accessing the track address at high speed, positioning it with high precision, and reading and writing information of a desired track address. This high-speed access positioning mechanism 24 includes an access arm 26 on which a plurality of magnetic heads 23 are mounted on one end of a carriage 25.
A voice coil section 27 is engaged with the other end of the carriage 25, and has a rotary positioning mechanism that swings around a pivot shaft 2 as a rotation axis. For this purpose, the conical member 44 has a forward access hole 4 through which the magnetic head 23 accesses the surface of the magnetic disk.
5, and in order to prevent the air flow containing foreign particles from flowing backward at the head access hole 45 without passing through the filter 42, a downwardly downward portion 46 is provided near the G1% disk surface 11. It is molded around the access hole 45. The air circulating in the sealing body 13 for removing foreign particles flows in the direction of the arrow in FIG. 2, and the collection and filtration of foreign particles is completed. FIG. 6 shows an exploded perspective view of this embodiment of the conical dust filtering mechanism of the present invention. FIG. 4 shows an exploded perspective view of another embodiment, in which the circulating air flow hole portion of the conical member 4B has a portion 49 cut into the shape shown and an opening 50 formed by the cutting and bending. , the filter 42, the mounting parts 51, 52, 53, and the packing 47 are the same as those shown in FIG. 5, but the circulation efficiency is much improved compared to the structure shown in FIG.

〔Effect of the invention〕

As described above, according to the present invention, in addition to improving the air circulation system within the sealed body and the labyrinth sealing mechanism, by adopting a new conical dust filtration mechanism, foreign particles inside the sealed body can be completely and quickly complemented. It becomes possible to improve the filtration efficiency, and it is possible to provide an inexpensive magnetic disk storage device that is compatible with floppy disk devices and is a highly reliable, small, large-capacity magnetic disk device, which is the original objective.

[Brief explanation of the drawing]

FIG. 1 is a plan view showing an embodiment of a magnetic disk storage device according to the present invention, and FIG. 2 is a sectional view taken along the line A--A in FIG. FIG. 3 shows an exploded perspective view of an embodiment of the conical dust filtering mechanism of the present invention. FIG. 4 shows an exploded perspective view of a conical dust filtering mechanism according to another embodiment. [Explanation of symbols] 1... Magnetic disk assembly, 2... Rotation drive unit, 3... Magnetic disk drive motor, 9... Spindle housing, 10... Base, 1
DESCRIPTION OF SYMBOLS 1... Magnetic disk, 12... Hub, 200... Labyrinth structure, 15... Oil flow pool, 16... Disk spacer, 2... Magnetic head, 24... High-speed access positioning mechanism, 41...・Conical dust filtration mechanism, 42...filter, I43...air flow hole, 44...
- Conical member, 45...Access hole, 46...Down-down part, 47...Seal gasket. 1 figure f2 figure 73 figure f4 figure

Claims (1)

[Claims] In a magnetic disk device that self-circulates air by rotating a plurality of magnetic disks housed in a sealed body of a head disk assembly, a conical dust filtration system combines a flat conical member and a flat filter seven-seal packing. A mechanism, which is close to the magnetic disk surface on the outer circumferential side of the magnetic disk, is away from the magnetic disk surface on the inner circumferential side of the magnetic disk, and has an air flow hole and a head access hole in the flat conical member, and A magnetic disk storage device characterized in that the conical member has an upright portion around the head access hole and a conical dust removal mechanism disposed at a central position facing the upper magnetic disk of the magnetic disk assembly. Device.