JPH0330945B2 - - Google Patents

Description

[Detailed Description of the Invention] [Summary] The present invention provides a sealed magnetic disk device that includes:
The rotation shaft support means of the magnetic disk rotation mechanism is comprised of a central fixed shaft whose both ends are supported and fixed between the base body side and the cover body side constituting the airtight housing, and a central fixed shaft that is pivotally supported via a bearing to the fixed shaft and is magnetically supported. It is equipped with a hub mechanism that holds the disk medium, and a hollow rotating shaft to which the rotor of the drive motor is directly connected to one end. This not only prevents resonance of the plurality of magnetic disk media mounted on the central fixed shaft 23 via the hub mechanism, but also improves the ease of assembling the device. By isolating the stator from the medium atmosphere using a relatively thin non-magnetic isolation member, the device can be easily completely sealed.

[Industrial application field]

The present invention relates to improvements in magnetic disk devices, and in particular, in a sealed magnetic disk device, the rotating shaft support means of a magnetic disk rotation mechanism is made into a double support structure that is easy to assemble, and the rotating shaft support structure is designed to improve vibration resistance. It is related to.

A magnetic disk device generally includes a plurality of magnetic disk media mounted on a rotating spindle of a disk rotation mechanism via a hub mechanism, and at least one magnetic head for each magnetic disk medium surface. It consists of a head access mechanism that positions the magnetic head at a predetermined track position on the corresponding magnetic disk medium surface, and further includes a rotating spindle, a plurality of magnetic disk media attached to the hub mechanism, an access mechanism that supports the magnetic head, etc. is placed in an airtight housing to prevent dust and the like from the outside air from entering the atmosphere surrounding the magnetic disk medium.

The rotary spindle of the disk rotation mechanism in such conventional magnetic disk devices is often supported by the connected rotary drive motor, which is a so-called one-end support system. When the head actuator is operated at high speed in order to perform high-speed processing of recording and reproducing information, the disturbance generated at that time causes relative vibration between the rotating spindle and the base body, which causes problems in the recording and reproducing operations. There are problems that have a negative impact, and there is a desire to resolve these problems.

[Conventional technology]

In order to solve the above-mentioned problems, a magnetic disk device as shown in FIG. 2 has been proposed.

That is, in this conventional magnetic disk device, a plurality of magnetic disk media 1 are mounted on a rotating spindle 3 of a disk rotating mechanism via a hub mechanism 2.
A double support system is adopted in which one end is supported on the base body 4 side constituting the airtight housing, and the other end is supported on the cover body 5 side via a bearing 6, respectively.This system provides rigidity against vibrations. This prevents relative vibration between the rotating spindle and the base body caused by the high-speed operation of the head actuator 7.

In this case, a magnetic fluid seal 8a is provided between the rotating spindle 3 and the base body 4 side and the cover body 5 side.
8b is provided, and the hub mechanism 2 inside the cover body 5
The plurality of magnetic disk media 1 attached to the head, the head actuator 7 supporting the magnetic head, etc. are completely sealed from the outside air. Reference numeral 9 denotes a rotation drive motor directly connected to the rotation spindle 3 and disposed outside the base body 4.

[Problem that the invention seeks to solve]

By the way, in the case of such a conventional magnetic disk device, when assembling the device, the rotating spindle 3 is in an unstable free-standing state where it is merely pivotally supported on the base body 4 side via a bearing 6. Another problem is that it is not easy to assemble the other end of the rotary spindle 3 to the cover body 5 via a bearing 6 and to have both sides supported.

In addition, since part of the sealing between the inside of the cover body 5 and the outside air is achieved by the magnetic fluid seals 8a and 8b, pressure fluctuations in the disk atmosphere inside the cover body 5 while the magnetic disk medium 1 is being driven to rotate may cause
There is a disadvantage that the magnetic fluid seals 8a, 8b are destroyed. Therefore, in order to eliminate this inconvenience, a dustproof filter 1 is installed on the cover body 5 side as shown in the figure.
It is necessary to provide a ventilation hole 10 with a
It was difficult to create a completely sealed structure.

The present invention has been made to solve the above-mentioned conventional problems, and its purpose is to facilitate assembly of a rotating spindle system and to prevent vibrations caused by high-speed operation of the head actuator. ,
It is an object of the present invention to provide a novel magnetic disk device which has sufficient rigidity and also has a completely sealed structure inside a cover body.

[Means for solving problems]

In order to achieve the above object, the present invention connects the lower end of the central fixed shaft 23 to the base body 24, as shown in FIG.
A dual support structure is adopted in which the upper end is fixed to the cover body 25.

A hub mechanism 22 holding a plurality of magnetic disk media 21 is attached to the fixed shaft 23, and a hollow rotating shaft 30 to which a rotor 29a of a drive motor 29 is directly connected to the lower end is connected via a bearing 26. Seals such as magnetic fluid seals 28a and 28b, for example, magnetic fluid seals 28a and 28b, are provided between both ends of the central fixed shaft 23 and the rotating shaft 30 to isolate the space containing the bearing 26 from the medium atmosphere.

Further, the base body 24 is provided with a stator 29b that pairs with the rotor 29a of the drive motor 29 provided at the lower end of the rotating shaft 30, and the stator 29b
A relatively thin non-magnetic isolation member 31 for isolating the stator 29b from the atmosphere on the rotor 29a side is provided between the stator 29b and the rotor 29a so as to cover the stator 29b. A nearby base body 24 is provided with a heat radiation hole 32 that communicates with the outside from the stator 29b side.

[Effect]

In such a device configuration, the central fixed shaft 2
Since one end of 3 is mechanically fixed to the base body 24, assembly of the device is facilitated, and a dual support structure is adopted in which the central fixing shaft 23 is fixed on the base body 24 side and the cover body 25 side. Therefore, sufficient rigidity is maintained even against vibrations generated due to high-speed operation of the head actuator 27, and resonance is prevented. Also, the magnetic fluid seal 28
Since the disk atmosphere is not sealed by a and 28b, a completely sealed structure can be easily realized.

Furthermore, since the thin non-magnetic isolation member 31 provided between the stator 29b and the rotor 29a allows them to be placed close to each other, the rotational efficiency of the drive motor 29 does not decrease. Furthermore, the heat generated in the stator (winding part) 29b covered with this non-magnetic isolation member 31 is dissipated through the heat radiation holes 32, so the heat causes temperature fluctuations such as temperature differences within the sealed housing. There's nothing to do.

Further, since the rotor 29a of the drive motor 29 is disposed at a sufficiently distant position from the magnetic disk medium 21 by the hollow rotating shaft 30, the magnetic field generated by the rotor (magnet) is transmitted to the magnetic disk medium 21. It has no effect on

〔Example〕

Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a sectional view of a main part of an embodiment of a magnetic disk device according to the present invention.

In the figure, reference numeral 23 denotes a central fixed shaft whose one end is fixed to a base body 24. A hub mechanism 22 holding a plurality of magnetic disk media 21 is attached to the fixed shaft 23, and a drive motor is attached to the lower end. 29
A hollow rotating shaft 30 to which a rotor 29a is directly connected.
is pivotally supported via a bearing 26.

Magnetic fluid seals 28a and 28b are provided between both ends of the central fixed shaft 23 and the rotating shaft 30 to isolate the space containing the bearing 26 from the medium atmosphere, and the other end of the central fixed shaft 23 is provided with a cover body 25. It has a double support structure fixed to the

Further, the base body 24 is provided with a stator 29b that pairs with the rotor 29a of the drive motor 29 provided at the lower end of the rotating shaft 30, and the stator 29b
9b and the rotor 29a, the stator 29b
A thin plate-shaped non-magnetic isolation member 31 made of ceramics or resin material is provided to isolate the disc from the disk medium atmosphere, and the base body 24 near the stator 29b has heat radiation holes that communicate with the outside from the stator 29b side. 32 are provided.

In the figure, a head actuator 27 supports at least one magnetic head for each recording surface of the plurality of magnetic disk media 1 and positions the magnetic head at a predetermined track position on the corresponding recording surface of the medium. 33 is a magnetic seal that magnetically removes fine metal powder scattered from the rotor 29a of the drive motor 29.

In the magnetic disk device configured in this way, the lower end of the central fixed shaft 23 is mechanically fixed to the base body 24, so that assembly of the device is facilitated, and the central fixed shaft 23 is fixed at both ends. Since it has a support structure, sufficient rigidity is maintained even against vibrations generated due to high-speed operation of the head actuator 27, and the head actuator 27 is attached to the central fixed shaft 23 via the hub mechanism 22. This prevents the plurality of magnetic disk media 1 from resonating.

Further, the magnetic fluid seals 28a and 28b isolate the bearing 26 from the disk medium atmosphere and prevent dust, lubricating grease, etc. from the bearing 26 from entering the disk medium atmosphere. Since it is not used to seal the atmosphere, a completely sealed structure can be easily realized.

Heat generated from the windings of the stator 29b of the drive motor 29, which is a larger source of heat, is released to the outside air through the heat radiation holes 32, thereby preventing the temperature of the disk medium atmosphere from rising.

In addition, the drive motor 29 for rotating the medium is connected to the rotor 2.
9a is provided at a position sufficiently distant from the magnetic disk medium 21, and the rotor 29a and stator 29
Since the drive motor 29 and the drive motor 29 are arranged close to each other, the magnetic field from the drive motor 29 does not affect the magnetic disk medium 21, and the drive efficiency of the motor 29 does not decrease.

Incidentally, if a pressure difference occurs between the space between the central fixed shaft 23 and the rotating shaft 30 and the disk medium atmosphere side, the rotating shaft 30 may be provided with a communication hole equipped with a dust removal filter.

〔Effect of the invention〕

As is clear from the above description, according to the magnetic disk device according to the present invention, the vibration generated due to the high-speed operation of the head actuator causes the Not only is it possible to prevent the magnetic disk media from resonating, but also the ease of assembling the device is improved. Furthermore, it has many excellent practical effects, such as being able to easily realize a completely sealed structure that is clean and has little temperature fluctuation, and is extremely advantageous when applied to this type of magnetic disk device.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a main part showing an embodiment of a magnetic disk device according to the present invention, and FIG. 2 is a sectional view of a main part of a conventional magnetic disk device. In FIG. 1, 21 is a plurality of magnetic disk media, 22 is a hub mechanism, 23 is a central fixed shaft, and 24 is a hub mechanism.
is a base body, 25 is a cover body, 26 is a bearing, 27 is a head actuator, 28a, 28
b is a magnetic fluid seal, 29 is a drive motor, 29a
is a rotor, 29b is a stator, 30 is a rotating shaft, 31
Reference numeral 32 indicates an isolation member, 32 a heat radiation hole, and 33 a magnetic seal.

Claims (1)

[Scope of Claims] 1. In an apparatus configuration in which a magnetic disk medium 21, a rotation mechanism for rotating the medium, and a magnetic head for recording and reproducing information on the medium are arranged in an airtight housing, the medium rotation mechanism described above A central fixed shaft 23 whose both ends are supported and fixed to a base body 24 and a cover body 25 constituting an airtight housing; A hollow rotating shaft 30 is attached with a hub mechanism 22 that holds the
and seals 28a and 28b provided between both ends of the central fixed shaft 23 and the hollow rotating shaft 30 so as to isolate the space between them including the bearing 26 from the medium atmosphere; and the hollow rotating shaft 30. A rotor 29a provided at the lower end of the shaft 30 and a rotor 29a provided on the base body 24.
and a stator 29b provided in close proximity to the drive motor 29, the stator 2 of the drive motor 29 being mounted on the base body 24.
A relatively thin isolation member 31 is provided between the stator 29b and the rotor 29a to isolate the stator 29b from the media atmosphere, and a relatively thin isolation member 31 is provided to isolate the stator 29b from the media atmosphere. A magnetic disk device characterized in that a heat radiation hole 32 is provided to allow heat to escape.