JPH07264801A - Rotation mechanism and disk device - Google Patents

Abstract

(57) [Abstract] [PROBLEMS] To provide a rotating mechanism and a disk device that prevent slipping between a spindle and a bearing inner ring and prevent occurrence of off-track and head crash, and shortening of the life of the bearing. To aim. [Structure] A rotating body 11 fitted and supported on a shaft 10 via a ball bearing 13, a drive source 19 for rotating the rotating body 11 around a vertical shaft 10, a shaft 10 and a ball bearing.
And a slip prevention means (18) for preventing slip of the contact surface of the inner ring (16) preloaded in the thrust direction.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotating mechanism such as a magnetic disk and a disk device, and more particularly to a rotating mechanism and a disk device which prevent a spindle and a ball bearing inner ring from slipping.

Recently, a magnetic disk device for writing / reading information on / from a magnetic disk by a magnetic head is widely used as a peripheral device of a computer. Such devices tend to be compact, high-density, large-capacity, and high-speed access, and along with this, high-density disks with a narrow track pitch are mounted. Precision is required for the rotation of and the swinging of the head arm. In addition, the outer ring rotation of the ball bearing has become mainstream with the downsizing, so that the inner ring of the ball bearing is preloaded.

Therefore, if the frictional force between the inner ring of the spindle and the ball bearing is insufficient, there is a possibility that the inner ring will be displaced, which causes off-track due to the eccentricity of the rotation of the magnetic disk, shortens the service life due to abrasion, and causes dust. It is the cause of the outbreak. Then, the method of solving this is desired.

[0004]

2. Description of the Related Art A magnetic disk device is described in Japanese Patent Application No. 03-006055 filed by the present applicant, and a conventional example will be described below with reference to FIGS.

FIGS. 9A and 9B are a plan view and a side view of the magnetic disk device. As shown in the figure, the magnetic disk device is composed of a disk assembly section 1a and an actuator section 2a.

The disk assembly unit 1a includes a housing 11a supported by a spindle 10a via ball bearings (hereinafter referred to as bearings) 13a and 13b, and a plurality of magnetic disks.
3a, 3b, and so on are stacked and attached at equal pitches, and are clamped by the disc clamp 12 at the upper end. Also spindle 10b
Is fixed to the base frame 14 at the lower end. A motor M1 is provided around the spindle 10a between the bearings 13a and 13b, and the drive of the motor M1 rotates the housing 11a to rotate the magnetic disks 3a, 3b.

The actuator portion 2a has a magnetic head at the tip.
It is composed of an actuator 21a having a head arm 22a that holds a plurality of springs 20a, 20b, which carry 4a, 4b, and a voice coil motor (VCM: oscillating motor), and is fixed to the base frame 14 at the lower end. The actuator 21a is supported by the spindle 24a thus formed via bearings 23a and 23b.

The magnetic heads 4a, 4b, are assembled so that the surfaces of the magnetic disks 3a, 3b ,.
Therefore, due to the rotation of the magnetic disks 3a, 3b,-, the magnetic heads 4a, 4b, at the tips of the springs 20a, 20b, -float slightly above the surface of the magnetic disks 3a, 3b,-, and the actuator portion 21a.
Is reciprocally rotated in the directions of arrows A and B to be positioned on the target track, and the magnetic heads 4a, 4b.
Information is written / read to / from 3a, 3b.

Here, the bearings 13a, 13b, 23a, 23
Explaining how to use b, bearings 13a, 13b, 23a, 23
b is the rotation of the magnetic disks 3a, 3b, ─ and the actuator
In order to support the rotation of 21a, the inner rings of the bearings 13a and 23a are preloaded so that the inner ring and the outer ring are pressed against the balls.

That is, in FIG. 10, a part of the disk assembly portion 1a is omitted and the peripheral portions of the bearings 13a and 13b are enlarged and shown. The outer ring 15a of the bearing 13a is press-fitted into the housing 11a and the inner ring of the bearing 13a is pressed. 16a is fitted into the spindle 10a with a clearance (for example, a clearance of 3 to 12 μm), and the outer ring 15b of the bearing 13b is bonded to the housing 11a, and the inner ring 16b of the bearing 13b is bonded to the spindle 10a with a semi-curing adhesive.

Then, two disc springs 17a, 17b which face each other and are stacked above the bearing 13a are fitted on the spindle 10a, and the upper side is pressed by the sleeve S1 to make the disc springs 17a, 17b.
A preload is applied to the inner ring 16a in the thrust direction at the inner bottom surface of b, and the inner ring 16a, the ball B1, and the outer ring 15a are pressed against each other,
Along with this, the inner ring 16b, the ball B2, and the outer ring 15b are pressed against each other.

Further, in FIG. 11, a part of the actuator portion 2a is omitted and the peripheral portions of the bearings 23a and 23b are enlarged and shown. The outer ring 25a of the bearing 23a is the actuator 21a.
The inner ring 26a of the bearing 23a is pressed into the spindle 24
The outer ring 25b of the bearing 23b is fitted to the actuator 21a and the inner ring 26b is fitted to the actuator 21a.
Are bonded to the spindle 10a with a semi-curable adhesive.

Then, two disc springs 27a, 27b, which are stacked facing each other, are fitted on the inner ring 26a, and the upper side is pressed by the sleeve S2, and a preload is applied to the inner ring 26a at the inner peripheral lower surface of the disc springs 27a, 27b. The outer ring 25a, the ball B3, and the inner ring 26a are pressed against each other, and accordingly, the outer ring 25b, the ball B4, and the inner ring 26a.
b presses each other.

Further, in the magnetic disk device in which the diameters of the magnetic disks 3a, 3b, -are 5 inches or more, the spindles 10a, 24a are further added.
By embedding the coil springs C1 and C2 and the pressing pins P1 and P2 in the radial direction, the inner rings 16a and 26a of the bearings 13a and 23a are preloaded in the radial direction to prevent rattling and eccentricity.

In the magnetic disk device in which the diameters of the magnetic disks 3a, 3b, -are 3.5 inches or less, the inner ring and the outer ring are bonded with a semi-curable adhesive. The reason is that the diameter of the spindles 10a and 24a may be too small to embed the coil springs C1 and C2 and the pressing pins P1 and P2 in the spindles 10a and 22a, but since the rotating body is small, the inner rings 16a and 26a and the spindles
The eccentricity of the outer rings 15a, 25a due to the sliding of 10a, 24a is small,
This is because the influence of the eccentricity of the magnetic disks 3a, 3b, ... Or the actuator 21a is small and can be omitted. In other words, it is not necessary to set the inner ring in a free state unlike a large-sized magnetic disk device.

[0016]

According to the above-mentioned conventional method, the outer rings 15a, 25a of the bearings 13a, 23a are fastened to the housing 11a, the actuator 21a by press fitting, and the inner rings 16a, 25a.
26a is in a free state with a gap fitted to the spindles 10a, 24a, and the outer rings 15b, 25b and inner rings 16b, 26b of the bearings 13b, 23b are made of a semi-hardening adhesive for the housing 11a and the actuator 21a. Bonded, inner ring 16
Preload is applied to a and 26a in the thrust direction.

Further, in a device in which the diameters of the magnetic disks 3a, 3b, -are 5 inches or more, the inner rings 16a, 26a are also preloaded in the radial direction. However, in such a structure, since the inner rings 16a, 26a of the bearings 13a, 23a are in a free state, the friction force between the spindle and the inner ring becomes insufficient, and the inner rings 16a, 26a of the bearings 13a, 23a rotate. As a result, the eccentricity of the outer rings 15a, 25a causes rotational vibration and displacement, which causes the magnetic head to shift from the track of the magnetic disk during seek, resulting in off-track. There is a problem that an error occurs, and the bearings 13a and 23a are worn, so that the life of the bearings is shortened and the head crashes due to the generation of dust.

The present invention provides a rotating mechanism and a disk device capable of preventing the inner ring between the spindle and the bearing from being displaced, thereby preventing vibration noise, off-track and head crash, and shortening the life of the bearing. Has an aim.

[0019]

1 and 2 are principle diagrams of the present invention. FIG. 1 is a principle diagram corresponding to claim 1, and FIG. 2 is a principle diagram corresponding to claim 2.

1) Means Corresponding to Claim 1 In FIG. 1, 10 is a shaft, 13 is a ball bearing, 16 is an inner ring, 11 is a rotating body fitted and supported by the shaft 10 via a ball bearing 13, 19 Is a drive source for rotating the rotating body 11 about the shaft 10, and 18 is a slip preventing means for preventing the contact surfaces of the shaft 10 and the inner ring 16 preloaded in the thrust direction of the ball bearing 13 from sliding. 2) Means corresponding to claim 2 In FIG. 2, 3 is a disk, 4 is a head, and 10A is the first.
Vertical axis, 13A is the first ball bearing, 16A is the first
Inner ring, 23 is a second ball bearing, 24 is a second vertical shaft, 26 is a second inner ring, 11 is a first vertical shaft 10A fitted and supported by a first ball bearing 13A, and the disk 3
A disk rotating body that holds and rotates the head horizontally; 22 is a head arm provided on the head rotating body 21 and having the head 4 at the tip; 21 has a head arm 22; and a second ball on the second vertical shaft 24. A head rotating body that is supported via a bearing 23 and that rotates the head arm 22, 18 is a first vertical shaft 10A.
And the contact surface of the first inner ring 16A, which is preloaded in the thrust direction of the at least one first ball bearing 13A, and the thrust direction of the second vertical shaft 24 and the at least one second ball bearing 23. It is a slip prevention means for preventing the contact surface of at least one of the contact surfaces of the second inner ring 26 from slipping.

Therefore, the rotating head 4 is opposed to a predetermined position on the surface of the rotating disk 3, and information is recorded or reproduced by the head 4 on the surface of the disk 3.

[0022]

Operation 1) Operation corresponding to claim 1 When the rotating body 11 is rotated by the drive of the drive means 19, the slip prevention means 18 prevents the contact surfaces of the shaft 10 and the inner ring 16 of at least one ball bearing 13 from sliding. Therefore, the eccentricity of the outer ring of the ball bearing 13 is prevented, and accordingly, the vibration of the rotating body 11 and the displacement of the rotation position are prevented, so that vibration noise is generated, the life of the ball bearing 13 is shortened due to wear, and dust is generated. Can be prevented.

2) Corresponding action to claim 2 When the disk 3 rotates and the head 4 rotates, the slip preventing means 18 includes the first vertical shaft 10A and at least one first shaft.
Contact surface of inner ring 16A of second ball bearing 13A, second vertical shaft 24 and at least one second ball bearing 23
Since the sliding of at least one of the contact surfaces of the first ball bearing 13A and the second ball bearing 23 is prevented, the eccentricity of the outer ring of at least one of the first ball bearing 13A and the second ball bearing 23 is prevented. Seek and data errors due to vibration and off-track of at least one of rotation are prevented, high density and high speed access are possible, and vibration noise, bearing life shortening and dust generation are prevented. can do.

[0024]

Embodiments 1 to 5 in which the present invention is applied to the magnetic disk device described in the conventional example will be described below with reference to FIGS. The same reference numerals denote the same objects throughout the drawings.

Further, Example 1 corresponds to Claims 1, 2 and 3 of the present invention, and Examples 2, 3 and 4 correspond to Claims 1 and 2 of the present invention. The fifth embodiment corresponds to claims 1, 2, and 4 of the present invention.

1) First Embodiment FIGS. 3 and 4 are block diagrams showing a first embodiment of the present invention.
4 is a side sectional view of the disk assembly portion, and FIG. 4 is a side sectional view of the actuator portion.

The spindle 10a, housing 11a, and
The bearings 13a and 13b, the disc springs 18a and 18a, and the motor M1 are
Corresponding to the vertical shaft 10, the rotating body 11, the ball bearing 13, the slip prevention means 18 and the drive source 19 of FIG. 1, the spindle 10a and the bearings 13b and 13c of FIG. 3 correspond to the first vertical shaft of FIG.
It corresponds to 10A and the first ball bearing 13A respectively.

The actuator 21a, bearings 23b and 23c, disc springs 28a and 28b and swing motor M2 shown in FIG.
Corresponding to the rotating body 21, the ball bearing 13, the slip prevention means 18 and the drive source 19 of FIG. 4, respectively, and the bearings 13a and 13b, the actuator 21a, the bearings 23a and 23b and the spindle of FIG.
Reference numeral 24a denotes a first ball bearing 13A, a head rotating body 21, a second ball bearing 23 and a second vertical shaft 24 shown in FIG.
The inner ring 16c and the inner ring 26c in FIG. 4 correspond to the first inner ring 16A and the second inner ring 26 in FIG. 2, respectively.

As shown in FIG. 3, the disc springs 18a, 18b for preloading the inner ring 16c of the bearing 13c of the disk assembly 1b, the portion where the inner ring 16c and the sleeve S3 are in contact, that is, the disc spring 18a,
The upper and lower surfaces a and b inside 18b, the upper surface c of the inner ring 16c and the lower surface d of the sleeve S3 are roughened.

As shown in FIG. 4, the actuator section
Belleville springs 28a, 28 for preloading the inner ring 26c of the bearing 23c of 2a
The portions where b contacts the inner ring 26c and the sleeve S4, that is, the upper and lower surfaces A and B inside the disc springs 28a and 28b, the upper surface C of the inner ring 26c and the lower surface D of the sleeve S4 are roughened.

The roughening method is carried out, for example, by processing the areas a to d and A to D on the surfaces a to d and A to D which are in contact with each other with sandpaper having a mesh size of medium or more or sandpaper having a viscosity of 300 or less. Make the surface rough.

With this structure, the housing 11a is rotated by driving the motor M1 and the swing motor M2,
When the head arm 21a rotates, the disc springs 18a, 18b, 28
Friction increases due to contact between the rough surfaces of a, 28b and the inner rings 16c, 26c and sleeves S3, S4, and the spindles 10a, 24a and inner rings
Sliding of 16c and 26c is prevented respectively.

2) Second Embodiment FIG. 5 is a constitutional view showing a second embodiment of the present invention, FIG. 5 (a) is a side sectional view of a disk assembly portion, and FIG. The rubber 18c and the groove 100 of FIG. 5 correspond to the slip prevention means 18 of FIGS.

As shown in FIG. 5, a groove 100 is provided on the spindle 10b of the disk assembly portion 1c, and a member made of a material having a high coefficient of friction, such as rubber 18c, is provided so as to slightly project from the upper surface of the groove 100. Is fitted.

Since the bearing has such a structure,
The inner ring 16a of 13a is preloaded by the disc springs 17a and 17b, and when the housing 11a is rotated by the drive of the motor M1, the friction between the rubber 18c and the inner ring 16a is large. Sliding is prevented.
Although not shown, the actuator unit can be similarly applied.

3) Third Embodiment FIG. 6 is a constitutional view showing a third embodiment of the present invention, FIG. 6 (a) is a side sectional view of a disk assembly portion, and FIG.

Coil springs 18A to 18D and counterbore holes shown in FIG.
101a to 101d and 160a to 160d correspond to the slip prevention means 18 shown in FIGS. As shown in FIG. 6, counterbore holes 101a to 101d, 160a to 160d are provided on the opposing surfaces of the sleeve S5 of the disc assembly portion 1d and the inner ring 16d of the bearing 13d, respectively.
Coil springs 18A to 18D are inserted into the respective springs after being compressed to a predetermined elastic force.

With such a structure, the coil spring
18A-18D always apply preload to the inner ring 16d,
When the housing 11a is rotated by driving the motor M1, the lateral stiffness of the coil springs 18A to 18D prevents the spindle 10a and the inner ring 16d from slipping. Although not shown, the actuator unit can be similarly applied.

4) Fourth Embodiment FIG. 7 is a side sectional view showing a fourth embodiment of the present invention. The keyways 102a, 162a and the key 18d in FIG. 7 correspond to the slip prevention means 18 in FIGS.

As shown in FIG. 7, key grooves 102 and 161 are provided at positions facing the spindle 10c of the disk assembly portion 1e and the inner ring 16e of the bearing 13e, and the key 18d is inserted and joined to the key grooves 102 and 161. Where the keyway 16
In order to make effective the preload in the thrust direction by the disc springs 17a, 17b, 1 is formed large so as to have a gap above the key 18d as shown in the figure.

With this structure, when the housing 11a is rotated by the drive of the motor M1, the spindle 10a and the inner ring 16d are engaged by the engagement of the key 18d and the key grooves 102, 161.
Are prevented from slipping and rotate together. Although not shown, the actuator unit can be similarly applied.

5) Fifth Embodiment FIG. 8 is a side sectional view showing a fifth embodiment of the present invention. The recess 103 and the adhesive 18e in FIG. 8 correspond to the slip prevention means 18 in FIGS.

As shown in FIG. 8, the spindle 10d of the disk assembly portion 1f is provided with a shallow and wide area recess 103,
The semi-hardening adhesive 18e injected into the recess 103 bonds the spindle 10d and a part of the inner ring 16a of the bearing 13a.

With such a structure, when the housing 11a is rotated by the drive of the motor M1, the spindle
Since 10d and the inner ring 16a are bonded by the adhesive 18e, the spindle 10d and the inner ring 16a are prevented from sliding. Although not shown, the actuator unit can be similarly applied.

In the second, fourth and fifth embodiments described above, the slip preventing means (rubber,
Although keys and adhesives) are provided, it is needless to say that they may be provided both above and below.

In the above example, the friction is generated or fixed on the upper surface or the upper portion of the inner ring to prevent rotation, but the opposed surfaces of the spindle and the inner ring may be roughened. But,
Considering the balance of the upper and lower bearings and the height accuracy, the method of this embodiment is preferable.

In the above example, the case where the radial preload is applied to the bearing has been described, but the invention can be similarly applied to the case where the radial preload is not applied. Also, I explained the case of the device that made the inner ring of the bearing free.
The same can be applied to a structure in which the outer ring is in a free state and a preload is applied to the outer ring side.

In the above example, the case of the magnetic disk device has been described, but the present invention can be similarly applied to an optical disk device, a floppy disk device and the like.

[0049]

As described above, according to the present invention, in claim 1, when the rotating body is rotated by the driving of the driving means, the contact surface between the vertical shaft and the inner ring of at least one ball bearing is caused by the slip preventing means. Since the outer ring of the ball bearing can be prevented from eccentricity, vibration and displacement of the rotational position due to eccentricity of the rotating body, shortening of life due to wear of the ball bearing and generation of dust can be prevented. .

In the second aspect, when the disk rotates and the head rotates, the slip preventing means includes the first vertical axis and the contact surface of the inner ring of the at least one first ball bearing and the second vertical axis. Since the contact surface of at least one of the contact surfaces of the at least one second ball bearing is prevented from slipping, eccentricity of the outer ring of at least one of the first ball bearing and the second ball bearing is prevented, and the disc Seek and data errors due to off-track due to vibration and / or eccentricity of at least one of rotation and head rotation are prevented, high density and high speed access are possible, vibration noise is generated, and life is shortened due to wear of bearings. Also, it is possible to prevent the generation of dust.

According to the third aspect of the present invention, the contact surface between the preload spring and the inner ring is made rough so that the inner ring of the shaft and the ball bearing can be easily prevented from slipping. In claim 4,
By fixing a part of the contact surfaces of the inner ring of the shaft and the ball bearing with an adhesive, it is possible to easily prevent the inner ring of the shaft and the ball bearing from slipping. There is an effect.

[Brief description of drawings]

FIG. 1 is a principle diagram corresponding to claim 1 of the present invention.

FIG. 2 is a principle diagram corresponding to claim 2 of the present invention.

FIG. 3 is a configuration diagram showing a first embodiment of the present invention (No. 1)

FIG. 4 is a configuration diagram (part 2) showing the first embodiment of the present invention.

FIG. 5 is a configuration diagram showing a second embodiment of the present invention.

FIG. 6 is a configuration diagram showing a third embodiment of the present invention.

FIG. 7 is a side sectional view showing a fourth embodiment of the present invention.

FIG. 8 is a side sectional view showing a fifth embodiment of the present invention.

FIG. 9 is a configuration diagram showing a magnetic disk device to which the present invention is applied.

FIG. 10 is a side sectional view showing a disk assembly portion of a conventional example with a part thereof omitted.

FIG. 11 is a side sectional view showing an actuator of a conventional example with a part thereof omitted.

[Explanation of symbols]

1a to 1f are disk assembling parts, 2a and 2b are actuator parts, 3,3a and 3b are magnetic disks, 4,4a,
4b is a magnetic head, 10 is an axis,
10A is the first vertical axis, 10a to 10d, 24a and 24b are spindles, 11 is a disk rotating body, 13 is a ball bearing,
13A is the first ball bearing, 13a to 13e,
23a to 23c are bearings, 16 is an inner ring, 16A is a first inner ring,
16a to 16e, 26a, 26b are inner rings, 17a, 17b, 1
8a, 18b, 27a, 27b, 28a, 28b are disc springs, 18 is a slip prevention means,
18c is rubber, 18d is key,
18e is an adhesive, 18A to 18D are coil springs,
19 is a drive means, 21 is a head rotating body,
21a is an actuator, 22 and 22a are head arms, 23 is a second ball bearing, 23a and 23a
b is the bearing, 24 is the second vertical axis, 24a
Is the spindle, 26 is the second inner ring, 100
Is a groove, 101a to 101d, 160a to 16
0d is a counterbore hole, 102 and 161 are keyways, 10
3 is a dent, M1 is a motor, M2 is a swing motor

Claims (4)

[Claims] 1. A rotating body (11) fitted and supported by a shaft (10) via a ball bearing (13), and a drive source (1) for rotating the rotating body (11) about the shaft (10). 1
9) and a slip prevention means (18) for preventing the contact surface of the inner ring (16) preloaded in the thrust direction of the shaft (10) and the ball bearing (13) from being slipped. Rotation mechanism. 2. A disk rotating body (11) which is inserted and supported by a first vertical shaft (10A) through a first ball bearing (13A) and which horizontally holds and rotates the disk (3), and a tip thereof. A head arm (22) having a head (4) is supported by a second vertical shaft (24) through a second ball bearing (23) and rotates the head arm (22). The moving head (4) is provided with a moving body (21), and the rotating head (4) is opposed to a predetermined position on the surface of the rotating disk (3). A disk device for recording or reproducing data, wherein the first vertical axis (10A) and at least one of the first vertical axis (10A)
Contact surface of the first inner ring (16A) preloaded in the thrust direction of the first ball bearing (13A), and the thrust direction of the second vertical shaft (24) and at least one of the second ball bearings (23) Preventing means (1) for preventing the contact surface of at least one of the contact surfaces of the second inner ring (26) which is preloaded by
A disk device characterized by having 8). 3. The slip prevention means (18) is provided with the inner ring (1).
6), or the contact surface between the preload spring and the inner ring (16) for preloading at least one of the first inner ring (16A) and the second inner ring (26), or the preload spring and the first inner ring ( 16A) and at least one of the second inner ring (26) has a rough contact surface, and the rotating mechanism and the disk device according to claim 1 or 2. 4. The rotation mechanism and disk device according to claim 1, wherein the slip prevention means (18) fixes a part of the contact surface with an adhesive.