JP3026194B2 - Recording device and fine positioning device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording device and a fine positioning device, and more particularly, to a recording device and a fine positioning device capable of realizing high-speed and high-resolution access.

[0002]

2. Description of the Related Art FIG. 6 is a schematic diagram showing an example of a conventional hard disk drive. This hard disk device 5
00 is a head slider 5 having a tapered flat shape.
01, a head portion 502 formed on a side surface of the head slider 501, a suspension 503 for holding the head slider 501, a carriage 504 for mounting the suspension 503, and a rotating shaft 50 of the carriage 504.
5, a voice coil motor (VCM) 506 for swinging the carriage 504, and a magnetic disk 507. The magnetic disk 507 includes the spindle shaft 50
It is fixed at 8. These are respectively arranged on a base and housed in a frame (all are not shown). The head slider 501 is provided on the magnetic disk 507.
Floating due to the rotation of.

At present, the recording density per unit area in a hard disk drive is increasing at an accelerated rate. Until now, the increase in recording density has been about 25% per year, but in recent years it has reached about 60%. Accordingly, a head positioning mechanism that enables high-speed and high-resolution access is required. In response to these requirements, for example, a technique for reducing the translational force acting on the pivot shaft by using two voice coil motors, a technique using a two-stage actuator for coarse movement and fine movement, and the like have been developed.

[0004]

However, in realizing high-speed and high-resolution access, the conventional hard disk device 500 has a problem that the entire device vibrates due to a seek reaction force, and seek time is increased. . In addition, there is a problem that positioning accuracy is reduced due to backlash or non-linear behavior of the bearing (rotating shaft 505).

[0005] Further, as the recording density increases, the tendency of downsizing of the hard disk drive will be promoted in the future. However, in the above-mentioned conventional hard disk drive 500, the VCM 506 is used for positioning the head section 502. ,
There is a problem that it is difficult to reduce the size of the device.

Accordingly, the present invention has been made in view of the above, and an object of the present invention is to provide a compact recording apparatus and a minute positioning apparatus which can realize high-speed and high-resolution access.

[0007]

According to another aspect of the present invention, there is provided a recording apparatus that records data on a recording medium and reproduces the data recorded on the recording medium. A suspension for fine movement, a suspension for coarse movement which is integrated with the suspension for fine movement and supports the fine movement suspension so as to be swingable in the scanning direction of the recording medium, and a beam part having one end fixed and the other end free. A first driving unit that is formed and provided with a piezoelectric body for each beam portion, vibrates the beam portion to contact the beam portion with the fine movement suspension, and drives the fine movement suspension; By forming a beam portion in both directions and providing a piezoelectric body for each beam portion, vibrating the beam portion and bringing the beam portion into contact with the coarse movement suspension. Second driving the dynamic suspension
And a drive unit.

The operation of the first and second drive units will be described. When a piezoelectric body is provided on the beam and a voltage is applied to the piezoelectric body, the beam vibrates. The vibrated beam portion comes into contact with the suspension for fine movement or coarse movement, and the head portion swings due to a lateral component force. The spring constants of the fine movement suspension and the coarse movement suspension are set based on their shapes and materials so that the head portion moves without difficulty. If such a beam is provided in both directions, the head can be moved in both directions. A voltage having a resonance frequency is applied to the beam. The moving speed and the resolution are determined by such conditions as the frequency and the amplitude of the beam.

As described above, by using the first drive unit and the second drive unit, the seek operation and the following operation can be performed efficiently. For example, the seek operation is performed by the second drive unit, and the following operation is performed by the first drive unit. Further, the first drive unit and the second drive unit may be used together to perform a seek operation or a following operation. In addition, since control is performed using two actuators, the first drive unit and the second drive unit, there is no need to switch between seek control and following control. Next, since the suspension for fine movement and the suspension for coarse movement are integrated, the structure is simple and the manufacture becomes easy. Also,
Since the mounting process can be omitted, product accuracy is improved.

[0010] Next, a recording apparatus according to a second aspect of the present invention includes a head unit for recording data on a recording medium and reproducing the data recorded on the recording medium, a fixing unit for fixing the recording medium to a frame side, and A coarse movement suspension integrally provided on the fixed portion via a first support portion, a fine movement suspension integrally provided on the coarse movement suspension via a second support portion, and holding a head portion; A free long beam portion is formed bidirectionally, a piezoelectric body is provided for each beam portion, and the beam portion is vibrated to bring the beam portion into contact with the fine motion suspension, thereby driving the fine motion suspension. (1) a driving portion and a short beam portion having one end fixed and the other end free, are formed bidirectionally, and a piezoelectric body is provided for each beam portion; A second driving unit for driving the coarse suspension by contacting, those having a.

The second drive section has a long beam, and is suitable for large movement. The first driving section drives the head section by the vibration of the short beam section, and thus is suitable for minute movement. Therefore, the seek operation and the following operation can be efficiently performed by performing the seek operation by the second drive unit and the following operation by the first drive unit. Further, since the coarse movement suspension and the fine movement suspension are integrally formed, the structure is simple and the manufacture is easy. In addition, since the mounting step can be omitted, the product accuracy is improved. Further, since the fine movement suspension and the device degree suspension can be formed into a plate-like structure, the structure can be manufactured by a semiconductor process and can be made compact.

Next, a fine positioning device according to a third aspect of the present invention provides a fine positioning device, a coarse movement suspension integrally provided on the fixed portion via a first support portion, and a second support portion on the coarse movement suspension. A fine movement suspension and a beam part having one end fixed and the other end free are formed bidirectionally and a piezoelectric body is provided for each of the beam parts, and the beam part is vibrated to make the beam part and the fine movement A first drive unit for driving the fine movement suspension by contacting the suspension and a beam portion having one end fixed and the other end free are formed bidirectionally, and a piezoelectric body is provided for each beam portion to vibrate the beam portion. And a second drive unit that drives the coarse motion suspension by bringing the beam portion into contact with the coarse motion suspension.

The operating principle of the beam is as described above. By using the long beam and the short beam together, the seek operation and the following operation can be performed efficiently, and high-speed and high-resolution access can be realized. . Further, since the coarse movement suspension and the fine movement suspension are integrally formed, the structure is simple and the manufacture is easy. In addition, since the mounting step can be omitted, the product accuracy is improved.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the drawings. The present invention is not limited by the embodiment.

FIG. 1 is a schematic assembly diagram showing a hard disk drive according to an embodiment of the present invention. FIG. 2 shows FIG.
FIG. 3 is an enlarged view showing the driving unit shown in FIG. FIG. 3 is a partial sectional view of the hard disk device shown in FIG. The hard disk device 100 includes a magnetic disk 2 attached to a spindle shaft 1, a fixed portion 3 fixed to a main body frame (not shown), a first support portion 4 extending from the fixed portion 3,
Coarse suspension 5 supported by the first support 4
And a second support 6 extending from the coarse suspension 5
A fine movement suspension 7 supported by the second support 6, a head slider 8 fixed to the fine movement suspension 7, a head 9 formed on a side surface of the head slider 8, a fine movement suspension 7 and a coarse movement suspension 5, a driving unit 10 arranged below the driving unit 10,
And a power supply 12 for driving.

The head slider 8, the fine movement suspension 7, and the coarse movement suspension 5 constitute a flying head mechanism. The magnetic disk 2 has a magnetic recording layer formed by applying an oxide on the disk base surface,
Any of magnetic materials sputtered may be used. The magnetic layer of the magnetic disk 2 is thin and has high coercive force;
It is preferable that the magnetic material has fine particles and a uniform surface. A ferrite head, MIG (Metal In
Gap) head, thin film head, MR (Magneto Resistiv)
e) Any of the heads may be used. MR head is suitable for high recording density. Note that a head using near-field light may be used instead of the magnetic head.

The coarse movement suspension 5 and the fine movement suspension 7 (suspension) have an integral structure together with the fixed part. Further, the suspension is a plate-like body formed by a processing process. The coarse movement suspension 5 has a quadrangular shape with a hollow portion. A first support portion 4 extends from one side of the coarse suspension 5 and is connected to the fixed portion 3. Also, a second support portion 6 extends from one side of the coarse movement suspension 5 inside,
It is connected to the suspension 7 for fine movement. Stainless steel or copper-based material is used for the material of the suspension.

The first support and the second support regulate the width of the extending support according to the swinging distance of the coarse movement suspension 5 and the fine movement suspension 7, and determine the spring constant. In this embodiment, the spring constant is 1 gf
/ Mm or less is desirable.

The driving section 10 includes a first driving section 110 for driving the fine movement suspension 7 and a coarse movement suspension 5.
And a second driving unit 120 for driving the driving. The first drive unit 110 and the second drive unit 120 are formed on the same drive unit substrate 101. On the drive unit substrate 101 relating to the first drive unit 110, fine movement beams 111 fixed at one end and free at the other end are formed bidirectionally (fine positioning device). The direction in which the fine movement beam 111 is formed is substantially the same as the radial direction of the magnetic disk 2. The fine movement beam 111 is formed to face the fine movement suspension 7. When the fine movement beam 111 vibrates, a part thereof comes into contact with the fine movement suspension 7. The fine movement beam 111 is formed using a photofabrication technique such as etching. By using a non-machining process, deformation, stress, and mechanical stress generated at the time of working formation can be eliminated, and function and reproducibility are stabilized. Also, the piezoelectric elements 1 are provided on the back side of the fine movement beam 111, respectively.
12 are on display.

Similarly, the driving substrate 101 relating to the second driving unit 120 is also provided with the coarse motion beam 12 fixed at one end and free at the other end.
1 are formed bidirectionally. However, since the coarse motion beam 121 is used for coarse motion, it is longer than the fine motion beam 111. The coarse movement beam 121 is formed to face the coarse movement suspension 5. Coarse beam 121
Vibrates, so that a part thereof comes into contact with the coarse suspension 5. Also, on the back side of the coarse motion beam 121,
Each has a piezoelectric element 122 spread thereon.

The piezoelectric elements 112 and 122 generate a stress or a displacement in accordance with an applied voltage, generate a resonance phenomenon in accordance with the frequency of the applied voltage, and exhibit a characteristic that a voltage is generated in accordance with an applied pressure. It is. For the piezoelectric elements 112 and 122 of this example, thin-film lead zircon titanate having a high piezoelectric constant is used. Further, barium titanate, lithium niobate, lead zirconate titanate, or the like may be used.
Also, instead of these piezoelectric ceramics, a functionally graded material or lithium niobate can be used.

The piezoelectric elements 112 and 122 are formed by a thin film forming process. This is because it is suitable for mass production.
In addition, since the size of the beam portion is small, the manufacture is easy. The beams 111 and 121 and the piezoelectric element 112,
122 may be integrated by bonding. The bonding interface at this time must be very thin and hard, tough, and have a small resistance value near the resonance frequency after bonding. For example, a polymer adhesive represented by hot melt and epoxy resin is used as the adhesive. Note that the beam portions 111 and 121 are of a unimorph type using one piezoelectric element 112 or 122, but may be of a bimorph type using two piezoelectric elements or a multimorph type using four or more piezoelectric elements. good.

The power supply 12 is connected to the piezoelectric element 1 via a wiring.
Power is supplied to the power supply 12 and 122. The seek / following control unit 11 controls the supply voltage based on a servo signal from the head unit 9.

Next, the operation of the hard disk device 100 will be described. First, the operating principle of each beam unit is shown in FIG. By applying a drive voltage of a specific frequency to the piezoelectric elements 112, 122, the piezoelectric elements 112, 12
2 expands and contracts in the direction of arrow A in the figure. Due to this expansion and contraction, the beam 1
11 and 121 vibrate in the direction of arrow B in the figure. Beam 11
When the beams 1 and 121 vibrate, the tips of the beams 111 and 121 come into contact with the suspensions 5 and 7. The contact direction is not perpendicular to the suspensions 5 and 7, but the arrow C in the figure.
It is the direction shown by. The suspensions 5 and 7 are bent by the force of the lateral force component Ch. This causes the suspensions 5, 7 to move laterally. Further, the specific frequency is matched with a natural frequency according to the size and shape of the beam portions 111 and 121. If it is set near the resonance frequency, the beam portions 111, 1
This is because a maximum amplitude of 21 is obtained. Fine beam 11
1 and the coarse motion beam portion 121 have different lateral force components due to the difference in length. For this reason, the movement amount of the fine movement suspension 7 by the fine movement beam portion 111 becomes fine, and the movement amount of the coarse movement suspension 5 by the coarse movement beam portion 121 becomes large.

Usually, positioning control in the hard disk drive 100 is performed by access speed control (seek control) and follow-up positioning control (following control). In the access speed control process, the head is moved at high speed from the current track to the target track. Next, in the following positioning control process, the head is made to precisely follow the track.

In the magnetic disk drive 100, the access speed control and the follow-up positioning control are performed in parallel, the access operation is performed at high speed by using the second drive unit 120, and the follow-up positioning operation is performed by the first drive This is performed precisely using the unit 110. Note that it is not always necessary to clearly separate the roles of the two, and the first driving unit 110 may be used for the access operation.

FIG. 5 is a block diagram of the positioning control system. In the seek / following control unit 11, first,
Detect the current head position. Subsequently, an operation amount is obtained based on the detected head position. The phase compensator controls the phase of the signal of the operation amount. The power amplifier amplifies the signal of the operation amount controlled by the phase controller. Then, the second driving unit 120 is driven according to the operation amount. Next, after the seek operation is performed, a track error signal is detected, and an operation amount is obtained based on the detected track error. The phase compensator controls the phase of the signal of the operation amount. The power amplifier amplifies the signal of the operation amount controlled by the phase controller. Then, the first driving unit 110 is driven according to the operation amount of the track error signal. By the seek operation and the following operation, a control amount with respect to the target value is obtained. Part of this control amount is converted into a signal of the same type as the target value signal, and is fed back to the input side.

[0028]

As described above, according to the recording apparatus of the present invention (claim 1), the fine movement suspension and the coarse movement suspension are integrally formed, and the first drive section for driving the fine movement suspension and the coarse movement suspension are provided. A second drive unit for driving the suspension. For this reason, switching between seek control and following control becomes unnecessary, and seek operation and following operation can be performed efficiently, so that high-speed and high-resolution access can be realized. Also,
The structure is simple, manufacturing is easy, and product accuracy is improved.

Next, a recording apparatus according to the present invention (Claim 2)
Comprises a fine movement suspension and a coarse movement suspension integrally, and a first drive section for driving the fine movement suspension and a second drive section for driving the coarse movement suspension are provided. Further, the beam portion of the first drive unit was shortened, and the beam portion of the second drive unit was lengthened. Therefore, the seek operation and the following operation can be efficiently performed by performing the seek operation by the second drive unit and the following operation by the first drive unit. Further, since the coarse movement suspension and the fine movement suspension are integrally formed, the structure is simple and the manufacture is easy. In addition, since the mounting step can be omitted, the product accuracy is improved. Furthermore, it can be made compact.

Next, in the fine positioning device according to the present invention (claim 3), the fine movement is performed by the first drive unit and the coarse movement is performed by the second drive unit, so that the seek operation is performed by the second drive unit. And the following operation can be performed by the first driving unit. Therefore, the seek operation and the following operation can be performed efficiently, so that high-speed and high-resolution access can be realized.

[Brief description of the drawings]

FIG. 1 is a schematic assembly diagram showing a hard disk drive according to Embodiment 1 of the present invention.

FIG. 2 is an enlarged view showing a driving unit shown in FIG.

FIG. 3 is a partial sectional view of the hard disk device shown in FIG.

FIG. 4 is an explanatory view showing the operation principle of each beam unit.

FIG. 5 is a block diagram showing a positioning control system.

FIG. 6 is a perspective view showing the structure of a conventional hard disk drive.

[Explanation of symbols]

 REFERENCE SIGNS LIST 100 hard disk drive 1 spindle shaft 2 magnetic disk 3 fixing part 4 first support part 5 coarse movement suspension 6 second support part 7 fine movement suspension 8 head slider 9 head part 10 drive part 11 seek / following control part 12 power supply 101 drive Substrate 110 First driving unit 111 Beam for fine movement 112 Piezoelectric element 120 Second driving unit 121 Beam for coarse movement 122 Piezoelectric element

────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Yoko Suzuki 1-8-1 Nakase, Mihama-ku, Chiba-shi, Chiba Seiko Instruments Inc. (56) References JP-A-62-214564 (JP, A) JP-A-4 -140074 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G11B 21/02 H02N 2/00 G05D 3/00

Claims (3)

(57) [Claims] 1. A recording and reproducing apparatus for recording and reproducing information on a recording medium.
It has a function to move the raw head to a predetermined position on the recording medium.
In example was the positioning mechanism, and a head portion for reproducing the data recorded in the recording and storage medium of data on the recording medium, and fine control suspension for holding a head portion, the fine control suspension becomes integral with fine control suspension A suspension for coarse movement that is swingably supported in the scanning direction of the disk diameter of the recording medium; and a bidirectionally formed beam portion having one end fixed and the other end free, and a piezoelectric body provided for each beam portion to vibrate the beam portion A first drive section for driving the fine movement suspension by contacting the beam section with the fine movement suspension, and a bidirectionally formed beam section having one end fixed and the other end free, and a piezoelectric body for each beam section. A second drive for driving the coarse movement suspension by vibrating the beam and bringing the beam into contact with the coarse movement suspension And a recording unit. 2. A piezoelectric providing a long beam portion has one end fixed and the other end free to the beam portion each thereby forming a two-way, to said beam portions by vibrating contacting the suspension the beam portion and flutter a first driving unit for driving the coarse movement suspension by the piezoelectric provided for each said beam portion short beam portion has one end fixed and the other end free so as to form a two-way, the beam to vibrate the beam portion parts and a second driving unit for driving the fine moving suspension by contacting the fine-movement suspension recording apparatus according to claim 1, further comprising a. A coarse movement suspension provided integrally with the fixed part via a first support part; a fine movement suspension provided integrally with the coarse movement suspension via a second support part; piezoelectric provided for each said beam portion a long beam portion has one end fixed and the other end free so as to form a two-way, flutter suspension by causing said beam portions to vibrate contacting the suspension the beam portion and flutter a first driving unit for driving the one end fixed and the other end of the piezoelectric arranged freely and the short beam portion to the beam portion each thereby forming a two-way, the beam portion by vibrating the beam portion and the fine-movement suspension fine positioning device characterized by comprising a second driving unit for driving the fine moving suspension by contacting and.