JP2003016741A - Disk unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a highly reliable disk unit in which the influence of dynamic external vibration or external shock is sufficiently suppressed. SOLUTION: A head disk assembly 22 consisting of a disk 1, a spindle motor 2, a head, a head supporting mechanism section 3 and a movable plate 20 is mounted on a mounting section 7 via a supporting member 21. The head supporting mechanism section 3 is constituted of a head arm 4, a supporting block rockably attached to the free end of the head arm 4 and a head slider 102 attached to the supporting block. The supporting block is attached in such a way that the centroid of the supporting block including the head slider 102 coincides with the axis to be an oscillating center in the direction vertical to the disk face. At this time, the natural frequency of the head disk assembly 22 is set so as to be equal to or below half of the natural frequency of the head supporting mechanism section 3 in the direction vertical to the disk face.

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hard disk drive
Information on disk-shaped recording media such as
The present invention relates to a disk device that performs recording and reproduction of data. 2. Description of the Related Art In recent years, as information recording / reproducing devices, hardware
Magnetic disk devices represented by disk devices and optical disks
The use of disk-shaped recording media such as
It is very popular. In particular, hard disk drives
Personal computer utilizing the high speed of data transfer
It is widely used as an external storage device such as a computer. [0003] In the following, a small hard disk drive that has become popular in recent years will be described.
A disk device will be described as a first conventional example with reference to the drawings.
explain. FIG. 11 shows a hard disk according to Conventional Example 1.
It is sectional drawing of an apparatus. FIG. 12 shows a hardware according to the conventional example 1.
FIG. 3 is a diagram showing a head support mechanism constituting the disk device.
FIG. 12A is a perspective view, and FIG.
Indicated by. [0004] As shown in the example of FIG.
The disk drive has a base 3 which forms a closed housing.
07 and cover 308, and a magnetically recordable medium
High-speed rotation while holding disk 301 and disk 301
Spindle motor 302 to be
Magnetic head for reading and writing recorded data
And a head slider 303 mounted with a head (not shown).
Suspension 304 for holding a head slider 303
And the head slider 30 via the suspension 304
3 for swinging the disk 3 in the in-plane direction of the disk 301.
And a tutor 305. Where the head
Slider 303 and suspension 304 are integrated
It is generically called a head support mechanism. [0005] As shown in FIG.
Axis 306 of the motor 302 and the head actuator 30
5 and the center axis 309 are both attached to the base 307
Have been. Therefore, the spindle motor 302 and the head
In the actuator 305
The degree is constrained by base 307. FIG. 1 shows a head support mechanism shown in FIG.
2 will be described. As shown in FIG.
(Not shown), the head slider 303
If you cantilever through the flexure 402 with
It is attached to a load beam 403 shaped like a bridge. Fret
Kisha 402 and load beam 403 are formed of a thin metal plate
These are combined to form the suspension 304
Is composed. [0007] The load beam 403 is
At the end opposite to the end where 3 is attached, mount 4
04 to the head arm 405
You. The head arm 405 is the head actuator shown in FIG.
It is connected to the tutor 305. [0008] The head slider 303
The surface of the disk 301 is
The disk rises due to the air film formed by the rolling
It follows the surface of 301. At this time, floating by air film
The force and the biasing force of the load beam 403 are balanced,
The flying height of the head slider 303 is constant. As described above, the hard disk drive of the first conventional example is
The disk 301 of the head slider 303
Is generated by the rotation of the disk 301.
It is performed by a non-contact method using an air film
You. However, due to such a structure, external
To the hard disk drive
When acceleration is applied to the head support mechanism,
The head slider 303 and the disk 30 are
The phenomenon of contact between the storage device and the storage device occurs.
There is a problem that the reliability of the system is lost. For example, in FIG.
Acceleration from 301 toward head support mechanism (upward in the figure)
When the degree is applied, the head support mechanism is indicated by an arrow.
Thus, a downward inertial force F is generated. In this case, the inertia force F
Therefore, the air film on the disk 301 is compressed, and the amount of compression is
The surface of the disk 301 and the surface of the head slider 303
If the distance is larger than the minimum distance, contact occurs. Also outside
When the acceleration from the section is released, the reaction force of the air film and the load
Due to the reaction force due to the elastic force of the beam 403, the head slider
Ida 303 jumps greatly from the surface of disk 301
And then collides with the disk 301. For this reason, for example, Japanese Patent Application Laid-Open No. 9-82052
Japanese Patent Laid-Open Publication No. Hei 11-39808 discloses a hard disk drive.
Head support mechanism for improving the reliability of disk devices
To reduce the effect of external acceleration on the vehicle
Some have been proposed. Next, the effect of external acceleration is reduced.
Of a conventional hard disk drive for the purpose of
Will be described as Conventional Example 2 with reference to the drawings.
You. FIG. 13 shows a hard disk drive according to Conventional Example 2.
FIG. 13 is a diagram showing a head support mechanism to be constituted, and FIG.
Is a perspective view, and FIG. 13B is a cross-sectional view. What
The hard disk device according to Conventional Example 2 is shown in FIG.
11 except for the head support mechanism shown in FIG.
It is configured in the same manner as the hard disk drive according to the first example.
Have been. [0014] As shown in FIG.
The head support mechanism that makes up the hard disk drive
Load beam extension 406 and metal body 40 on beam 403
7 is provided in the configuration shown in FIG.
Different from the head support mechanism of the first example, other components
Are substantially the same. Note that the conventional example 1 shown in FIG.
The same components as those of the head support mechanism are denoted by the same reference numerals.
Description is omitted. Further, as shown in FIG.
At the tip of 405, a notch 405b is provided.
You. The load beam extension portion 406 is provided for the load beam 403.
And inside the notch 405b.
It fits in. The metal body 407 has a predetermined mass.
At the end of the load beam extension 406.
It is placed. Load beam extension 406 and metal body
In the design of 407, the center of gravity of the head support
Near the boundary between the arm 403 and the head arm 405,
Indicates a boundary line 4 between the load beam 403 and the mount unit 404
05a. As described above, the head support mechanism according to the related art 2
Has a load beam extension 406 and a metal body 407.
Shock, even if an external shock is applied.
Velocity acts near the center of rotation (near boundary line 405a)
It will be. For this reason, the movement of the head slider 303
The head slider 303 and the disk 30
Has the potential to reduce damage from collisions with
You. [0017] However, the conventional example
In the head support mechanism according to the second aspect, one head support mechanism is provided.
And consider its static mass balance.
It can be said that it is just taking into account. Therefore, the actual dynamic
If the effects cannot be sufficiently suppressed with respect to
There is a problem. This problem is explained below in detail
I do. If the acceleration applied from the outside is static,
Things (for example, gravitational acceleration
), The head support according to Conventional Example 2
In the holding mechanism, the moment on the head slider 303 side
And the moment on the metal body 407 side are within the boundary line 405a.
The head slider 303 and disk
No force acts on the air layer formed between the
It can be said. Therefore, the head slider 303 and the disk 3
01 is reduced. However, the actual hard disk drive
The impact acceleration applied to the vehicle is not static and changes with time.
It has the chemical Also, such shock acceleration
Is often a pulse with a duration of a few milliseconds
It is. Therefore, when such an impact acceleration is applied,
When examining the effects of
It has to be considered that the behavior is dynamic. [0020] From a dynamic point of view, shock acceleration in a vibration system
When force is applied, forced displacement occurs due to inertial force
And free vibration was excited, and the impact acceleration was released
It is well known that sometimes free vibrations remain.
The head support mechanism according to Conventional Example 2 is not completely rigid.
Therefore, a vibration system that has a degree of freedom due to elastic deformation
Need to be considered. FIG. 14 shows a hard disk drive according to the conventional example 2.
Explain the dynamic behavior of the head support mechanism that composes the
FIG. 4 is a schematic view for illustrating a head support mechanism according to a dynamic model.
Indicated by. As shown in FIG.
The slider 303 is attached to the tip of the
The end of the load beam extension 406 has a metal body 407
Is attached. The slider 303 corresponds to an air film
Linear spring 410 supported against the disk 301
ing. Also, the load beam 403 is located at the rotation center (boundary
(Line 405a). More movable
The center of gravity of the entire part coincides with the rotation center 405a. A broken line in FIG. 14A indicates a head support mechanism.
Shows the state when vibrated, and the head support mechanism
It has a natural vibration mode of the shape shown by the broken line. For example,
When the metal body 407 is displaced downward in FIG.
As shown in (b), the linear spring 410 has a force F in the tensile direction.
1 works. On the other hand, the metal body 407 is displaced upward in the drawing.
When the linear spring 410 is moved as shown in FIG.
Exerts a force F2 in the compression direction. Therefore, this unique mode
When the vibration of the arm is excited, the air spring 410
A periodic force that repeats compression is applied. Here, as an example, the dimensions of the head slider
Method is 1.2mm × 1.0mm × 0.3mm, Suspension
The length of the section (total length of the load beam) is 11mm
We assumed a simple head support mechanism and evaluated it.
U. Evaluation works on air film when impact acceleration is applied
The magnitude (absolute value) Fa of the applied force is used as a measure of impact resistance.
went. In addition, the evaluation was performed using the head support mechanism of the conventional example 1.
And the head support mechanism in Conventional Example 2
Was. Hereinafter, Fa is referred to as “air film disturbance force”.
You. FIG. 15 shows a head support mechanism of the first conventional example.
Is a graph showing the air film disturbance force calculated in FIG.
Numeral 16 denotes an empty space calculated for the head support mechanism of Conventional Example 2.
It is a graph which shows a puffy membrane disturbance force. FIG. 15 and FIG.
In the calculation of the graph shown in FIG.
1000 times the acceleration (9.8 × 10 ^Three m / se
c ^Two ) For 1 millisecond (ms)
You. [0025] As shown in FIG.
In the holding mechanism, the air film disturbance force Fa is applied while the impact force is being applied.
(From the start to 1 ms) at the maximum value of 75 mN (7.7
gf). This force is due to the forced displacement.
You. In addition, the vacancy after the release of the impact force (after 1 ms from the start)
The film disturbance is due to residual vibration. On the other hand, the head support of the second prior art shown in FIG.
In the holding mechanism, during the application of the impact force for 1 ms from the start,
And the air film disturbance force Fa is reduced compared to the conventional example 1.
I have. However, the impact force was released 1 ms after the start
Then, due to the effect of the remaining free vibration, the maximum value of Fa
Is 136 mN (13.9 gf).
Head support mechanism. The reason
Is the mass of the movable part in the head support mechanism of Conventional Example 2.
However, it is about twice as large as that of the head support mechanism of the conventional example 1.
This is because the vibrating mass is large. As described above, the head support mechanism of the conventional example 2
Considers the head support mechanism as one rigid body,
It only considers the balance of static force (mass)
So it is excited when a real dynamic external shock is applied
Turbulence acts on the air film due to free vibration.
U. As a result, the air film is compressed and the head slider 30
3 comes in contact with the disk 301 or the head slider
Collision with disk 301 after 303 jumped up greatly
Or to happen. That is, the head support of Conventional Example 2
Holding mechanism can sufficiently suppress the effects of dynamic external acceleration.
I can't say that. An object of the present invention is to solve the above-mentioned problem and to provide a dynamic
Can sufficiently suppress the effects of external vibration or external shock.
To provide reliable and reliable disk drives.
You. [0029] To achieve the above object,
The disk device according to the present invention has a disk-shaped recording medium.
A body, a recording medium drive for rotating the recording medium,
Recording of information on a recording medium and reproduction of information from the recording medium
Prints the head, which performs one or both of them, and the head
A head support mechanism for supporting above the medium, and recording
Movable play with medium drive and head support mechanism
And a head disk assembly including at least
Attach the movable plate to the mounting
Has a structure that is mounted via a support member attached
The head support mechanism is centered on an axis parallel to the surface of the recording medium.
A swing member configured to be swingable as a center axis, and a swing member
The head slide that is attached to the end of the
And the swinging member includes a head slider.
The center of gravity when mounted is aligned with the center axis and the surface of the recording medium.
They are positioned so that they match in the vertical direction,
Eigen vibration determined from disk assembly mass and support member rigidity
The number of movements is perpendicular to the surface of the recording medium in the head support mechanism.
Set to be less than half the natural frequency in the desired direction
It is characterized by having been done. The disk device according to the present invention has
External vibration or external impact
High reliability because the impact of the strike can be sufficiently suppressed
Sex can be provided. DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a disk drive according to the present invention will be described.
An example of the arrangement will be described with reference to the drawings. Figure 1
FIG. 4 is a cross-sectional view illustrating a cross-sectional configuration of a disk device according to the present embodiment.
FIG. FIG. 2 shows the configuration of the disk device shown in FIG.
FIG. FIG. 3 shows the configuration of the disk drive shown in FIG.
FIG. 3 is an enlarged perspective view showing a part of a head support mechanism to be moved.
You. FIG. 4 is an exploded view of a part of the head support mechanism shown in FIG.
FIG. As shown in the examples of FIGS. 1 and 2, this embodiment
The disk device according to the form is a small hard disk device
It is. The disk device according to the present embodiment
And a recording medium for rotating the recording medium 1.
A recording medium driving unit 2 for recording information on the recording medium 1
Perform one or both of the reproduction of information from the body 1
A head (not shown) and supporting the head above the recording medium 1
Head support mechanism 3 for holding the recording medium drive 2
And the movable plate 20 on which the head support mechanism is mounted.
Has a head disk assembly 22 including at least
You. In the example of FIGS. 1 and 2, the recording medium 1
It is a magnetic disk with a recording layer capable of recording air
(Hereinafter, the recording medium is referred to as a “disk”.) this
Therefore, the head is a magnetic head. Also, a recording medium driving unit
2 has the function of holding the disc 1 and rotating it at high speed.
(Hereinafter, the recording medium drive unit is
Described as “spindle motor”. ). Spindle mode
The center axis 6 of the tab 2 is fixed to the movable plate 20.
The spindle motor 2 is configured to be rotatable with respect to the center shaft 6.
The degree of freedom other than the rotation direction is
Is bound by As shown in FIGS. 1 and 2,
The head support mechanism 3 includes a head arm 4, a swing member,
And a head slider 102. However, FIG.
2 and FIG. 2, the swing member is not shown.
This will be described later with reference to FIGS. 3 and 4.
You. As shown in FIGS. 3 and 4 described below, the head
Attached to the rider 102. The head arm 4 is parallel to the surface of the disk 1.
One end is movable so that it can swing in
Attached to the door 20. In the example of FIGS. 1 and 2,
Attach the head arm 4 to the movable plate
This is performed via the actuator 5 and the central shaft 9. During ~
The mandrel 9 is fixed to the movable plate 20. Head A
The actuator is rotatably mounted on the central axis 9
The degree of freedom other than the rotation direction is
Therefore it is restrained. Therefore, the head arm 4 is
With the power from the head actuator 5 about the shaft 9
The head slider 102 can be moved to the radius of the disk 1
Can be transported in any direction. Further, as shown in the examples of FIGS.
The head disk assembly 22 is
The movable plate 20 on the mounting part 7 for mounting
It is mounted via the attached support member 21. FIG.
In the example of FIG. 2 and FIG. 2, the support member 21 is configured by a pair of leaf springs.
The head disk assembly is supported by the support member 21.
Thus, it is supported on the mounting section 7. The mounting part 7 is
Combine with the bar 8 to seal the head disk assembly 22
To configure a housing. Further, the support member 21 is provided at both ends thereof.
And the center is screwed to the convex portion 7a of the mounting portion 7
7 is fixed. Further, the support member 21 is provided at both ends and the middle.
The middle point with the center is screwed to the convex part 20a of the movable plate 20
And is fixed to the movable plate 20. With this configuration, the head disk assembly 2
Reference numeral 2 denotes a plate spring that is a support member 21 with respect to the mounting portion 7.
Displaceable in the bending direction (Z direction indicated by the arrow in FIG. 2)
It becomes. 1 and 2, the head disk assembly
22 has a mass of 10 g and the Z direction of the leaf spring which is the support member 21.
Direction rigidity is 6.0 × 10 ^Five N / m. Yo
And the head disk assembly 22 is
The natural frequency when vibrating in the direction is 389 Hz. The head support mechanism 3 and the head
The configuration will be described with reference to FIGS. Figure
As shown in the example of FIG.
04. The oscillating member 104 is flat with the disk 1 surface.
It is configured to be swingable about the axis 103c as the center axis.
You. In the example of FIG. 3, the shaft 103c is free of the head arm 4.
A pair of toes fixed at the ends parallel to the surface of the disc
(Hereinafter, the axis is referred to as “torsion bar”).
Put on. ). The swinging member 104 is the head slider 1
02 (hereinafter referred to as swinging).
The member is described as "support block". ), On axis 103c
Fixed. As shown in the example of FIG.
The head 101 for recording and reproducing information on the head is a head slider.
It is integrally mounted on the tip of the die 102. 102b
On the surface of the head slider 102 facing the disk 1.
The air lubrication surface 102b provided. Head slider
102 is on the end face opposite to the face facing the disc 1
Through a gimbal spring 103a constituting a gimbal mechanism.
And is attached to the support block 104. Here, the gimbal spring 103a, the support block
And the torsion bar 103c together
Suspension 109 is generically called. Thus, the head
The supporting mechanism is a suspension 109, a head slider
102 and the head arm 4. As shown in the example of FIG. 4, the suspension shown in FIG.
The plate 109 is a plate member 10 formed of a thin metal plate.
3 and the support block 104 and the head slider 102 are connected.
It is constituted by joining by means such as wearing. Heads
The rider 102 supports the support block 10 via the plate member 103.
4 will be attached. The plate member 103 has a gimbal mechanism.
Gimbal spring 103a, head slider joint 103
b, torsion bar 103c, head arm joint 10
3d, support block joint 103e, and torsion bar
For connecting the gimbal spring 103a to the first 103c
103f is integrally formed. These are metallic
It is manufactured collectively by etching the thin plate
I have. The gimbal spring 103a is made of metal.
Is made by forming a thin plate into a cross shape.
Function. Therefore, the head slider 102 is
As shown in FIG.
Rotational degree of freedom around the axis and a straight line b perpendicular to it
The support block 104
Is supported with a predetermined rigidity. The torsion bar 103c is also a thin plate spring.
As a torsion spring.
Sufficient rigidity in other directions compared to torsional rigidity around center axis
It will be big. In other words, the torsion bar 10
3c is the self-displacement in the rotation direction about the center axis.
Has freedom. Thickness and width of torsion bar 103c
And length are torsional rigidity around the central axis and bending in the thickness direction
The stiffness is set to a predetermined value. For this reason, the support block joint 103e and
Support plate joined to the plate member 103 at the connecting portion 103f.
The lock 104 is a torsion bar 103 as shown in FIG.
c indicates the degree of freedom of rotation about the axis indicated by the straight line c.
To support the head arm 4 with a predetermined rigidity.
And Therefore, the support block 104 is
4. A swinging motion about the shaft member 103c is performed on
be able to. Also, as described above, the head slider 1
02 is attached to the support block 104,
This swinging motion is caused by the support block 104 and the head slider 1.
02 is performed integrally. The torsion bar of the support block 104
The head slider 102 is attached to the
The center of gravity of the support block 104 when attached
That is, the center of gravity of the head slider 102 and the support block 104
And the center of gravity of the torsion bar 103c
The center axis (straight line c) is perpendicular to the surface of the disc 1.
In the same way. Examples of FIGS. 3 and 4
Then, the above composite center of gravity is the center of the torsion bar 103c.
It is located on the axis (straight line c). As described above, the disk device of the present embodiment
, The suspension 109 has a predetermined mass and structure.
By including a support block 104 made of
The rotational moment of the slider 102 is canceled.
It is configured as follows. Therefore, the quality of the support block 104
The amount and position of attachment to the torsion bar 103c are
Is set according to the moment by the slider 102.
You. It should be noted that in the examples of FIGS.
The spring 103a and the head slider 102 are
It is performed by means such as adhesion through the pacer 106.
You. The head arm joint 103d and the head arm 4
Is joined by means such as welding. However,
In the present embodiment, the joining method is limited to the above method.
Not something. Because of the above configuration, FIG.
The head support mechanism shown in FIG.
The disk 101 can follow the disk 1. Immediately
That is, the bottom surface of the head slider 102 with the rotation of the disk 1
Air as a highly rigid air spring on the air lubrication surface 102b
A film is formed, and the head slider 102
Levitates in a non-contact manner to imitate the recording surface. At this time,
The head 101 moves the gin
Two straight lines a and b of the valve spring 103a are set as center axes.
Follows with rotational degrees of freedom. On the other hand, the height of the surface of the disk 1
For fluctuations, mainly torsion of the torsion bar 103c
With the spring characteristic, that is, the degree of freedom of rotation about the straight line c as the central axis
Follow. In the present invention, the head supporting mechanism is used.
In the part, the rotational moment by the head slider 102 is struck.
If it is a configuration that can be erased, the configuration shown in FIGS.
However, the present invention is not limited to this. For example, support block 1
The head arm 4 itself is used as a swing member instead of
There is a configuration that works. In this case, the head slider 1
02 is attached to the head arm 4
The direction perpendicular to the disk 1 surface with respect to the swing center of the arm 4
The head slider 102
Can cancel the rotational moment. The axis serving as the swing center of the swing member is as follows.
As can be seen from Fig. 5 below, the vertical direction of the movable plate
It is sufficient if the head is provided so as to follow the movement of the head.
It may be provided at any position of the support mechanism 3 (head
The door support mechanism 3 is mounted on the movable plate 20.
Me). Therefore, the state in which the head arm 4 itself becomes a swinging member.
In this case, the axis that is the swing center is located in the head arm.
It may be provided in the space between
It may be provided at the joint with the heater 5. Next, according to the present embodiment shown in FIG.
If the disk drive receives an external impact,
The operation of the disk device will be described with reference to FIG. Figure
5 illustrates the dynamic behavior of the head support mechanism shown in FIG.
FIG. FIG. 5A shows the present embodiment.
FIG. 5B shows a dynamic model of the disk drive, and FIG.
First natural oscillation in the disk device according to the embodiment
FIG. 5C schematically shows the operation mode, and FIG.
A schematic diagram of the second natural vibration mode in a disk drive
Is shown. As shown in FIG. 5A, a head slider
And a first rigid body 202 corresponding to
The second rigid body 204 is a torsion bar (shaft member).
They are connected by corresponding beams 203. First rigid body 202
And the second rigid body 204 at the center of gravity C on the beam 203
The third rigid body 220 corresponding to the movable plate 20
It is simply supported. Therefore, the first rigid body 22
0, the second rigid body 204, the beam 203 and the center of gravity C
Will follow the movement of the rigid body. Also, this center of gravity point
The axis passing through C serves as the swing center of the swing member. Furthermore, the first
Between the rigid body 202 and the third rigid body 220,
First spring 230 corresponding to an air film generated by rotation
Is provided. These components are head disks
It corresponds to the assembly 22. Further, the third rigid body 220 serves as a support member.
Through a corresponding second spring 221, a fixed portion corresponding to the mounting portion is provided.
It is attached to the fixed part 207. Where the first rigid body
202, the second rigid body 204, and the third rigid body 220
These are m1, m2, and m3, respectively. The first spring 23
0, the stiffnesses of the second spring 221 are k1 and k2. What
Note that m3 is not the mass of the movable plate alone,
This corresponds to the mass of the entire disk assembly 22. Therefore, m3
Is set sufficiently large compared to the values of m1 and m2.
I have. Also, k1 is set to be sufficiently larger than k2.
ing. The first natural vibration mode shown in FIG.
Are a first rigid body 202, a second rigid body 204, and a third rigid body
A vibration module in which the body 220 vibrates in the Z direction
In FIG. 1, the head disk assembly 22 is
Vibration in the bending direction of the leaf spring as the support member 21
Is equivalent to Natural frequency in the first natural mode
f1 is m corresponding to the mass of the head disk assembly 22
3 and k2 corresponding to the rigidity of the support member.
In this embodiment, the frequency is set to 389 Hz as described above.
Have been. Further, the second natural vibration mode shown in FIG.
The bending direction is mainly the bending direction of the beam 203 (perpendicular to the disk surface).
In a different direction). Form of this implementation
In the disk device according to the embodiment, the head support mechanism 3
Is smaller than the mass of the entire head disk assembly 22.
Because it is sufficiently small, the vibration of the head support mechanism 3 is
Has little effect on the vibration of the disk assembly 22
I can say. Therefore, the second natural vibration mode is substantially a head.
This is equivalent to the natural vibration mode of the support mechanism 3 alone. FIG. 6 shows a specific example of the head support mechanism shown in FIG.
Vibration mode, ie, calculation result of the second natural vibration mode
FIG. Eigen of this second natural vibration mode
The frequency f2 is 1554 Hz. As mentioned above,
In the embodiment, the entire head disk assembly vibrates.
Is the natural frequency of the head support mechanism.
About 1/4 times the second natural frequency f2 which can be regarded as
Is set to Next, the present embodiment configured as described above
In a disk drive,
A description will be made as to whether the influence of the impact is reduced. In general,
When impact acceleration is applied to the vibration system,
Free vibration is excited when forced displacement occurs
Are known. Here, the forcible displacement is defined by the external acceleration.
Inertia force, that is, displacement caused by external force of the vibration system
When the external force is released, the displacement is also released. Again
Free vibration is the balance of internal force of a vibration system regardless of external force.
This is the natural vibration that occurs and the impact acceleration is released
(After the impact acceleration is released, the free vibration
Movement is called residual vibration). Therefore, in this embodiment,
Behavior of disk drive in forced displacement and residual vibration
I will explain separately. First, while the impact acceleration is being applied,
The behavior will be described. In the dynamic model shown in FIG.
For example, for example, when the impact acceleration is
It is assumed that the voltage is applied. At this time, each rigid body has
Inertia obtained by multiplying the quantities m1, m2, and m3 by the acceleration a
The forces F1, F2, F3 act downward in the drawing. As mentioned above
Thus, in the present embodiment, inertial forces F1 and F2 are heavy.
Because it is configured to be balanced at the center point C, around the point C
Considering the moment balance, the first spring (air
It is considered that the reaction force from the spring) 203 always becomes zero.
In other words, no force acts on the air spring. This
Does not matter whether the suspension is elastically deformed or not.
To establish. Therefore, the forced displacement due to the inertial force
It does not give any disturbance. Next, the effect of the residual vibration will be described.
Generally, the vibration system has the waveform of the applied external acceleration and the
It is known to make a specific response depending on the time. Yo
Therefore, the relationship between input acceleration and vibration system response is
In the field, it is studied as a shock response spectrum.
You. According to the research results, for a vibration system with one degree of freedom
When the input acceleration satisfies the following two conditions,
It has been clarified that seismic vibration is significantly suppressed.
The first condition is that the acceleration waveform is symmetric (for example, a half sinusoidal wave).
And triangular wave), the second condition is that the input acceleration
The duration is sufficiently long compared to the period of the natural vibration of the vibration system.
(Hereinafter, when these two conditions are combined, “residual vibration
Motion suppression condition)). On the other hand, the waveform of the input acceleration
(For example, sawtooth wave), residual vibration is suppressed.
It is not controlled. The present invention utilizes the knowledge to
This is to improve the impact resistance of the device. That is, the real
The head support mechanism in the embodiment has a near natural frequency.
External shock acceleration because it can be regarded as a vibration system with one degree of freedom
Degree waveform and duration satisfy the above-mentioned residual vibration suppression condition.
It is considered that residual vibration can be suppressed. But di
The impact acceleration on the disk device
Various depending on the structure of the host device to be mounted and how to use it
And cannot define itself.
I can't say that. Therefore, the disk according to the present embodiment
In the device, any external
When acceleration is applied, the force applied to the head support
Specify that the speed always satisfies the above-mentioned residual vibration suppression condition
The structure, ie, the head disk assembly 22 shown in FIG.
A structure supported by the mounting unit 7 via the member 21;
ing. This will be described below with reference to FIG. FIG. 7 shows the dynamic input of the disk drive shown in FIG.
It is a block diagram showing an output relation. In FIG. 7, the arrow
b is the input acceleration to the head disk assembly, that is, movable
Represents plate acceleration. Arrow c indicates the head disk group.
Displays the output from the solid to the air film, that is, the air film disturbance force.
You. Arrow a indicates the input acceleration (impact acceleration) to the device.
Represents According to the present embodiment, as shown in FIG.
The characteristics of the disk drive are in the front stage of the head disk assembly.
Defines the input acceleration b to the head disk assembly.
The point is that a mechanical resonator which is an element for this purpose is provided. What
The mechanical resonator referred to in this specification is a head disk assembly.
Refers to a structure in which the body is supported on the mounting part by a support member
(See FIG. 1). The mechanical resonator is shown in FIG.
By utilizing the resonance of the first natural vibration mode, the head
A predetermined frequency acceleration is applied to the disk assembly. Subordinate
Therefore, in the disk device according to the present embodiment,
When any external acceleration (impact acceleration) is applied to
Is excited, and the head disk assembly
It always makes a simple oscillation of 389 Hz. For this reason, the head support
Substantially a 389 Hz sinusoidal acceleration is applied to the mechanism 3.
Will be obtained. Here, first, the sinusoidal vibration has a symmetric waveform.
Second, it is regarded as vibration of the head support mechanism alone.
The second natural frequency f2 to be applied depends on the entire head disk assembly.
Set about 4 times the natural frequency f1 at which the body vibrates
Therefore, the above two conditions for suppressing residual vibration are
Is pleased. Therefore, the remaining free vibration is greatly reduced
Will be done. As described above, the mechanical resonator shown in FIG.
Has a function to regulate the acceleration input to the
ing. In addition, the disk drive according to the present embodiment
The input acceleration a is the acceleration of a given waveform and frequency.
plays the role of a mechanical filter that converts to b
Can also be said. As described above, the display in the present embodiment is
With the above-mentioned configuration, the
The effects of both displacement and residual vibration can be eliminated. Next, the disk drive according to the present embodiment
In order to clarify the effect of FIG.
Calculation of air film disturbance force and acceleration of movable plate
Was done. This calculation is performed in the following first and second modes.
This is done for two aspects. First aspect
Is the disk device shown in FIG. 1 according to the present embodiment.
You. In the second mode, the rigidity of the support member 21 is sufficiently high, and
The acceleration of the mounting portion 7 is transmitted to the movable plate as it is.
Disk device, that is, the effect of the support member 21 is not obtained.
(Not in the state without the mechanical resonator shown in FIG. 7)
Other than the above, the same as the disk device according to the present embodiment
It is a disk device. In the above calculation, the impact
The velocity (external acceleration) is the same as FIG. 15 and FIG.
1000 times the force acceleration (9.8 × 10 ^Three m / s
ec ^Two ), A sawtooth waveform is applied for 1 ms. FIG. 8 shows a disk drive according to this embodiment.
Film disturbance force calculated for the device (first mode)
7 is a graph showing acceleration of a movable plate and a movable plate. FIG.
(A) shows the result of calculating the air film disturbance force, and FIG.
(B) shows the result of calculating the acceleration of the movable plate.
I have. FIG. 9 does not show the effect of the support member.
Air film calculated for the disk device (second embodiment)
4 is a graph showing a disturbance force and an acceleration of a movable plate.
You. FIG. 9A shows the result of calculating the air film disturbance force.
FIG. 9B shows the result of calculating the acceleration of the movable plate.
Is shown. As shown in FIG. 9, the second mode (mechanical resonance
External acceleration)
During 1 ms, the operation of the head support mechanism described above
Thus, it can be confirmed that the forced displacement is suppressed. Only
1 ms after the external acceleration is released,
Disturbing force is generated in an oscillating manner and is affected by residual vibration
It is recognized that. Although residual vibration has occurred,
In the head support mechanism of the embodiment, the head
Since the mass is balanced near the slider,
The movable mass is much smaller than that of the conventional example 2.
You. Therefore, the air film disturbance force is up to 57 mN
(5.8 gf), which is 136 m of the conventional example 2 shown in FIG.
N (13.9 gf) is significantly reduced. On the other hand, as shown in FIG.
Head (with a mechanical resonator)
The acceleration acting on the lock assembly is sinusoidally shaped.
Can be confirmed. Therefore, as shown in FIG.
, Forced displacement during 1 ms when external acceleration is applied
Is suppressed and the external acceleration is released
The residual vibration after 1 ms has also been significantly reduced. FIG.
In (a), the maximum value of the air film disturbance force is 4.1 m.
N (0.42 gf), which is 3% of Conventional Example 2 described above.
To a degree. In other words, compared to Conventional Example 2,
It can be said that the impact resistance is improved about 33 times. FIG. 10 shows a head device according to the present embodiment.
The effect of the natural frequency f1 of the disk assembly (mechanical resonator)
It is the graph shown. In FIG. 10, the horizontal axis is the head support.
Natural frequency f2 of the holding mechanism unit and head disk assembly
(Mechanical resonator) to the natural frequency f1 (frequency ratio (f
2 / f1)). The vertical axis indicates the maximum air film disturbance force.
The value is normalized with the state without mechanical resonator as 1,
That is, the air disturbance force in the second mode shown in FIG.
The relative value of the air turbulence force calculated with the large value as 1.
You. The calculation of the graph shown in FIG.
This is done by changing the value of 1 (natural vibration
The number f2 is a fixed value (1554 Hz)), and the natural frequency f1 is
The change depends on the support member 21 (leaf spring) shown in FIGS.
To change the flexural rigidity by using various shapes
Has gone by. Calculation of the graph shown in FIG.
In FIG. 15 also, the impact acceleration (external acceleration)
As in FIG. 16, the magnitude is 1000 times the gravitational acceleration.
(9.8 × 10 ^Three m / sec ^Two ) For 1ms for sawtooth waveform
Is applied. As shown in FIG. 10, the frequency ratio (f2 / f
If 1) is 2 or more, calculate the maximum value of the air film disturbance force.
Can be reduced to 50% or less of the state without mechanical resonator.
Call Furthermore, if the frequency ratio (f2 / f1) is 4 or more,
For example, it can be seen that it can be suppressed to 10% or less. The simulation shown in FIGS.
The disk device according to the present embodiment
Force displacement due to external impact acceleration and residual vibration
It can be confirmed that both can be reduced. Yo
Therefore, in the disk device according to the present embodiment,
The shock resistance has been greatly improved compared to conventional disk units.
It can be said that. In general, an insulator or vibration insulation
Using a member called the body to reduce the effect of external vibration
Although there is a prior art, the mechanical resonator in the present invention is
Are completely different in purpose and function from the prior art.
Because of the prior art insulator or vibration isolation
The damping structure using the edge is used for the impact acceleration input to the device.
The goal is to reduce the amount of decay, decrease the decay, and shorten the decay time.
It is the target. In contrast, the machine of the present invention
The resonator measures the impact acceleration to the device with the specified waveform and frequency.
It is intended to convert the
Reduction, attenuation, and reduction of the decay time are not necessarily the objectives.
Absent. For example, as can be seen from FIG.
The maximum value of the impact acceleration applied to the device is 1000G
Of the acceleration acting on the head disk assembly
The maximum value is almost the same, and the acceleration is reduced.
No. In addition, attenuation is also performed in the time direction
It can be said that it has not been done. In the present embodiment,
Even under such conditions, as shown in FIG.
The effect that the disturbance force can be significantly reduced is obtained. This
Therefore, the mechanical resonator according to the present embodiment has
Different from conventional technology using insulator or vibration insulator
It is clear that it is a technology. It should be noted that the above-described directory according to the present embodiment is
In the disk device, in order to clarify the difference from the conventional technology,
Dare to reduce or attenuate the impact acceleration due to the mechanical resonator
It is configured to have no conditions. However, in the present invention
Disk device is limited to such a configuration
Instead, use a configuration that can reduce or attenuate acceleration.
Can also be. For example, in parallel with a leaf spring serving as a support member or
A structure in which a material with a large damping effect is inserted in series
You can also. Furthermore, instead of leaf springs, viscoelastic properties
Using a support member made of a material having
The movable plate and the mounting part are connected
You can also. In this embodiment, a hard disk drive
However, the present invention is not limited to this.
Not something. In the present invention, for example, the optical head is
Optical disk device mounted on the Ida
No. As described above, the disk drive according to the present invention
According to the location, when an impact acceleration is applied from the outside,
Compared to the conventional disk drive, the head and the recording medium
Touching can be avoided. Therefore, the disk according to the present invention is
Using a disk device, for example, storage of a hard disk device
By configuring the device, the reliability against external shocks is greatly improved.
An improved storage device can be provided.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a cross-sectional view showing an example of a cross-sectional configuration of a disk device according to the present embodiment. FIG. 2 is a plan view showing the configuration of the disk device shown in FIG. FIG. 4 is an enlarged perspective view showing a part of a head support mechanism part of the disk device shown in FIG. 4; FIG. 4 is an exploded perspective view showing a part of the head support mechanism part shown in FIG. FIG. 6 is a schematic view for explaining the dynamic behavior of the head support mechanism shown in FIG. 6. FIG. 6 is a perspective view showing the calculation result of the natural vibration mode of the head support mechanism shown in FIG. 3. FIG. FIG. 8 is a block diagram showing the mechanical input / output relationship of the apparatus. FIG. 8 is a graph showing the air film disturbance force and the acceleration of the movable plate calculated for the disk apparatus according to the embodiment. Discs according to the present embodiment except for those not present FIG. 10 is a graph showing the air film disturbance force and the acceleration of the movable plate calculated for the same disk device as the device. FIG. 10 is a graph showing the effect of the natural frequency of the head disk assembly (mechanical resonator) in the present embodiment. FIG. 11 is a cross-sectional view of a hard disk drive according to Conventional Example 1; FIG. 12 is a view showing a head support mechanism configuring the hard disk drive according to Conventional Example 1; FIG. 13 is a head support configuring a hard disk drive according to Conventional Example 2; FIG. 14 is a schematic diagram for explaining the dynamic behavior of a head support mechanism constituting the hard disk drive according to Conventional Example 2. FIG. 15 is an air film calculated for the head support mechanism of Conventional Example 1. FIG. 16 is a graph showing a turbulence force. FIG. 16 is a graph showing an air film turbulence force calculated for the head support mechanism of Conventional Example 2. [Description of Signs] 1 Recording medium (disk) 2 Recording medium drive (spindle motor) 3 Head support mechanism 4 Head arm 5 Head actuator 6 Center axis 7 Mounting section 7a Projection section of mounting section 8 Cover 9 Center axis 20 Movable plate 20a Movable plate Part 21 support member 22 head disk assembly 101 head 102 head slider 102b air lubrication surface 103 plate member 103a gimbal spring 103b head slider joint 103c shaft member (torsion bar) 103d head arm joint 103e support block joint 103f joint 104 Support block 106 Spacer 109 Suspension 202 First rigid body 203 Beam 204 Second rigid body 207 Fixed part 220 Third rigid body 221 Second spring 230 First spring

   ────────────────────────────────────────────────── ─── Continuation of front page    (72) Inventor Shio Den             Matsushita Electric, 1006 Kadoma, Kazuma, Osaka             Sangyo Co., Ltd. F term (reference) 5D059 AA01 BA01 CA21 CA25 CA26                       DA11 EA08                 5D068 AA01 BB01 CC12 EE01 GG03

Claims (1)

Claims: 1. A disk-shaped recording medium, a recording medium driving unit for rotating the recording medium, and recording of information on the recording medium and reproduction of information from the recording medium. A head for performing one or both of them, a head support mechanism for supporting the head above the recording medium, and a movable plate on which the recording medium driving unit and the head support mechanism are mounted The disk assembly
The head disk assembly has a structure in which the head disk assembly is mounted via a support member attached to the movable plate, and the head support mechanism has an axis parallel to a surface of the recording medium. A rocking member configured to be rockable as a central axis, and at least a head slider mounted on the end of the rocking member and mounting the head, wherein the rocking member is
The center of gravity when the head slider is attached is arranged so as to coincide with the center axis in a direction perpendicular to the surface of the recording medium, and natural vibration determined by the mass of the head disk assembly and the rigidity of the support member The disk device is characterized in that the number is set to be equal to or less than half the natural frequency of the head support mechanism in the direction perpendicular to the surface of the recording medium.