JPH06231534A - Disk drive - Google Patents

Abstract

PURPOSE:To provide a disk drive whose bearings are protected from damage by fixing disks on opposite sides of a flange of a hub using a clamping means to offset the stress acting when they are fixed. CONSTITUTION:Magnetic disks 3, 4 are fixed on opposite sides of a flange 8 of a hub 1 by clamp means of a male screw 6 and a female screw 7. Accordingly, a stress acting when the disks 3, 4 are fixed is cancelled at both ends of the flange 8 of the hub 1 in a direction of a rotating axis 42, and influence to the hub 1 to a shaft 2 is eliminated. Therefore, bearings 13, 14 are not affected by influence of a moment of an unbalanced force due to the stress, not damaged, and generation of vibration, noise is prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording disk drive device for rotationally driving a recording disk such as an optical / magnetic disk.

[0002]

2. Description of the Related Art As a recording member, for example, there is a magnetic disk drive device for rotating and driving a magnetic disk to read / write information. An example of such a magnetic disk drive device is disclosed in Japanese Patent Application Laid-Open No. 62-287466. In this device, a plurality of magnetic disks formed by punching the central portion are stacked and mounted on a hub having a substantially bowl shape. A pair of bearings are mounted between the hub and the bracket so that the hub is relatively driven by a rotor magnet provided inside the hub and an armature provided inside the bracket. . Along with this, the magnetic disk fixed integrally with the hub is rotationally driven.

[0003]

By the way, in order to mount a plurality of magnetic disks on a hub and fix the hub integrally with the hub,
A clamp member is used. However, when the clamp member is fixed to the hub by screwing, the stress acting on the hub by screwing acts on the bearing as a moment of unbalanced force, resulting in damage to the bearing. As a result, vibrations and noise are generated in the bearing, which may lead to read / write failures in the magnetic disk drive device.

The present invention has been made in view of the above problems existing in the prior art. The problem is that even if a plurality of recording disks are stacked on a hub and mounted, It is an object of the present invention to provide a highly reliable recording disk drive device that does not damage a bearing that rotatably supports a hub, and thus has a small vibration and noise and does not cause a read / write failure of a recording disk.

[0005]

In order to achieve the above object, the recording disk drive apparatus of the present invention is provided by the following means. That is, a recording disk having a flat plate shape and having a coaxial hole formed in the center thereof, a hub member to which the hole of the recording disk is externally fitted and mounted, and the recording disk being the hub. A recording disk drive comprising: clamp means for pressing and fixing to a member; and drive means for rotationally driving the hub member; the hub member extends radially outwardly over the entire circumference. The recording disk, the recording disk is held by abutting the flange portion to both ends in the rotation axis direction,
The recording disk drive device is clamped and fixed by the clamp means via the collar portion.

[0006]

The plurality of recording disks are fixed by being clamped by the clamp means via the collar portion provided on the hub. At this time, the stress acting when the recording disc is clamped and fixed by the clamp means acts to cancel the recording discs held at both ends of the flange portion in the direction of the rotation axis. Then, the stress is similarly canceled at both ends of the flange portion provided so as to intervene in these recording disks. Therefore, substantially no stress acting on the collar portion in the direction of the rotation axis is exerted by the clamping means, and thus the hub integrated with the collar portion is not affected.
Therefore, the bearing that rotatably supports the hub does not receive the moment of unbalanced force due to such stress and is not damaged.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a recording disk drive device according to the present invention will be described with reference to FIGS. Figure 1
FIG. 3 is a cross-sectional view of a main part showing a part of a first embodiment of a magnetic disk drive device that rotationally drives a magnetic disk, for example. The first embodiment shows a magnetic disk drive device in which two magnetic disks are mounted and rotationally driven. It should be noted that, in the figure, a portion for rotationally driving the magnetic disk is shown, and illustrations of other magnetic heads, actuators and the like are omitted. In FIG. 1, magnetic disks 3 and 4
Each has a thin plate shape, and a coaxial hole (center hole) is formed at the center thereof. A plurality of holes for mounting and fixing to the hub 1 described later are provided at the edges of the center holes of the magnetic disks 3 and 4.

The member 2 is a shaft as a stationary member, and is made of iron material. Both ends of the shaft 2 are fixed to upper and lower base members constituting the present driving device. The upper base member 9 is attached to the upper portion of the shaft 2 and is inserted into a hole 23 (not shown) provided in the upper end of the shaft 2.
It is fixed integrally by screwing the mounting screw. A hole 20 is provided in the lower base member 10, and the shaft 2 is press-fitted and fixed in the hole 20.
At the lower part of the shaft 2, there is a stepped portion 11 which is formed coaxially with a diameter corresponding to the hole 20, and is mounted at this portion.

A pair of bearings 13 and 14 are mounted on the shaft 2, and the hub 1 is rotatably supported via the bearings 13 and 14. The hub 1 has a substantially cylindrical shape formed coaxially with the rotation axis 42 and is made of a magnetic stainless material. The flange portion 8 is integrally formed on the outer peripheral surface 28 of the hub 1. The collar portion 8 forms the maximum outer diameter of the hub 1 and is formed so as to project outward in the radial direction over the entire circumference, and also in the longitudinal direction of the hub 1 (direction of the rotation axis 42).
Is located substantially in the center. The thickness of the collar portion 8 is set so that the magnetic disks 3, 4 when mounted
It is set according to the required clearance dimension between them. Further, both end portions of the flange portion 8, that is, the upper end portion 24 and the lower end portion 25, respectively, form a plane defined substantially at right angles to the rotation axis 42. Therefore, the central holes of the magnetic disks 3 and 4 are coaxially fitted to the outer peripheral surface 28 of the hub 1, and the height dimension is positioned by the collar portion 8. The two magnetic disks 3 and 4 mounted on the flange 8 are defined in a state perpendicular to the rotation axis 42.

The collar 8 is provided with a plurality of holes 38 which are formed so as to penetrate in the direction of the rotation axis 42. Hole 3
The flanges 8 are arranged at equal intervals in the circumferential direction, and correspond to holes provided at the edges of the magnetic disks 3 and 4 at the center. Therefore, when the magnetic disks 3 and 4 are held in the collar portion 8 and screwed through the hole portion 38 by the clamping means by the male screw 6 and the female screw 7, the magnetic discs 3 and 4 pass through the collar portion 8. It is pinched and fixed. Male screw 6
A seal member 41 is attached to the end surface of the female screw screwed with the seal member 41. This is provided so that when the male screw 6 and the female screw are screwed together, biting scraps are generated and are not scattered into the magnetic disk indoor space 35. In this way, the magnetic disks 3 and 4 are fixed to the collar portion 8 and the hub 1
Will be supported as a unit. The portion 27 provided at the lower end of the hub 1 is a locking hole formed to prevent rotation of the hub 1 when fixing the magnetic disks 3 and 4 to the hub 1. A protruding member (not shown) is fitted into the locking hole 27 to fix the magnetic disks 3 and 4 in a state where the rotation of the hub 1 is restricted.

A rotor magnet 44 is annularly arranged at a substantially central portion of the inner peripheral surface 19 of the hub 1. The rotor magnet 44 has N poles and S poles with a predetermined number of magnetic poles in the circumferential direction.
The poles are magnetized alternately. This rotor magnet 4
The armature 15 is arranged on the outer peripheral surface 18 of the shaft 2 so as to face the inner surface 4 (inward in the radial direction). The armature 15 is composed of a stator core 17 in which a required number of electromagnetic steel sheets are laminated, and an armature coil 16 wound around the stator core 17. The coil lead wire 26 of the armature coil 16 is led out of the drive device through the through hole 12 formed in the shaft 2. The rotor magnet 44 and the armature 15 constitute drive means for rotationally driving the hub 1. When a predetermined electric signal is applied to the coil lead wire 26, the hub 1 and the shaft 2 are driven by their electromagnetic action. And are driven to rotate relative to each other.

Annular members 21 and 22 are provided on the upper and lower ends of the pair of bearings 13 and 14, that is, on the outer sides of the bearings 13 and 14 in the direction of the rotation axis 42, respectively.
Each of the annular members 21 and 22 is in contact with and fixed to the inner peripheral surface 19 of the hub 1. Then, for example, the annular member 21
The inner peripheral surface 29 of the tip, which projects radially inward, is arranged so as to face the outer peripheral surface 18 of the shaft 2 with a slight gap. The same applies to the annular member 22. Therefore, the annular members 21, 22 and the outer peripheral surface 18 of the shaft 2 form a labyrinth seal structure. For this reason, the lubricant and unclean air existing in the space 34 inside the hub 1 will not be absorbed by the magnetic disk indoor space 35.
Leakage is prevented.

The feature of the present embodiment is that, in the configuration described above, the magnetic disks 3 and 4 are clamped at both ends of the collar portion 8 of the hub 1 by the clamping means by the male screw 6 and the female screw 7. It was fixed. Therefore, the stress acting when the magnetic disks 3 and 4 are clamped and fixed by the clamp means is canceled at both ends of the collar portion 8 of the hub 1 in the direction of the rotation axis 42, and the hub 1 is influenced by the shaft 2. Never. Therefore, hub 1
The pair of bearings 13 and 14 that rotatably support is not affected by the unbalanced force moment due to such stress. In this way, the bearings 13 and 14 are not damaged and vibration and noise are prevented from occurring.

Next, a second embodiment of the recording disk drive device of the present invention will be described with reference to FIG. Figure 2
FIG. 2 is a cross-sectional view showing a state in which six magnetic disks are mounted, in which the magnetic disks are rotationally driven as in FIG. 1.
Note that, in FIG. 2, the upper and lower base members and the like constituting the present drive device are omitted. Then, the contents overlapping with the parts already explained are omitted, and different parts will be explained. In FIG. 2, both ends of the collar portion 62 of the hub 52, that is, the upper end portion 85 and the lower end portion 86 are
Three magnetic disks 63, 64, 65 and 6 respectively
6, 67, 68 are attached. Further, spacers 78, 79 and 80, 81 are interposed between these magnetic disks. These magnetic disks are clamped by a male screw 71 and a female screw 70 which are clamp means 69,
It is integrally fixed to the hub 52. In the case of the second embodiment as well, as in the first embodiment, the magnetic disk is sandwiched by the clamp means 69 via the collar portion 62 and fixed to the hub 52.

The member 48 inside the hub 52 is provided.
And 56 are magnetic fluid sealing devices. The magnetic fluid sealing devices 48 and 56 are fixed to the inner peripheral surface 51 of the hub 52 via holding members 50 and 55 formed of a non-magnetic material (for example, an aluminum material). The internal space 74 of the hub 52 and the indoor space 75 of the magnetic disk are sealed by the magnetic fluids 49 and 57 held in the gap between the shaft 46 and the outer peripheral surface 47.

As described above, the second embodiment also has the same characteristics as the first embodiment, and the stress exerted by the clamp means 69 has an effect on the bearings 53 and 54 that rotatably support the hub 52. Never give. In particular, when a large number of magnetic disks are stacked and fixed to the hub as in the second embodiment, this configuration is extremely effective. In addition,
Various mounting numbers can be selected in addition to the above-described embodiment in which three magnetic disks are symmetrically arranged on the rotation axis 73 via the collar portion 62. Correspondingly, the height position of the collar portion 62 can be changed as appropriate.

The embodiment of the recording disk drive device according to the present invention has been described above in detail, but the present invention is not limited to this, and may be freely modified within the scope of the present invention. For example, although the example of screwing with a male screw and a female screw is used as the clamping means, a cylindrical member for engagement having different inner diameters is used, and an uneven portion formed by an elastic member is engaged. It can be freely selected, for example. The shape and thickness of the collar portion can be set freely.

[0018]

Since the recording disk drive device of the present invention has the above-mentioned structure, it has the following effects. Even if multiple recording discs are stacked on the hub and mounted, the bearings that rotatably support the hub are not damaged, and thus vibration and noise are small, which may cause read / write failures of the recording discs. Therefore, a highly reliable recording disk drive device can be obtained.

[Brief description of drawings]

FIG. 1 is a fragmentary sectional view showing a part of a recording disk drive device according to a first embodiment of the present invention.

FIG. 2 is a cross-sectional view of essential parts showing a part of a recording disk drive device according to a second embodiment of the present invention.

[Explanation of symbols]

1, 52, hub 2, 46 shaft 13, 14, 53, 54 bearing 8, 62 collar portion 5, 69 clamp means 44, 77 rotor magnet 15, 76 armature 3, 4, 63, 64, 65, 66, 67 , 68 magnetic disk

Claims (1)

[Claims] 1. A recording disk having a flat plate shape and having a coaxial hole formed in the center thereof, a hub member to which the hole of the recording disk is fitted and mounted, and the recording disk. A recording disk drive device comprising: a clamp means for pressing and fixing the hub member to the hub member; and a drive means for rotationally driving the hub member. The recording disk has a flange portion formed so as to project over the circumference, and the recording disk is held by abutting the flange portion on both ends in the direction of the rotation axis, and clamping by the clamp means via the flange portion. A recording disk drive device characterized in that it is fixed.