Remote-operated integrated microactuator, in particular for...

Details Remote-operated integrated microactuator, in particular for... Remote-operated integrated microactuator, in particular for...

1999-07-20

2004-10-26

Miller, Brian E. (Department: 2652)

Dynamic magnetic information storage or retrieval

Head mounting

For adjusting head position

C360S294600

Reexamination Certificate

active

06809907

ABSTRACT:

TECHNICAL FIELD
The present invention relates to a remote-operated integrated microactuator. In particular, an integrated microactuator according to the present invention may be advantageously, but not exclusively, used to actuate read/write transducers of hard disks.
BACKGROUND OF THE INVENTION
As is known, hard disk actuating devices having a dual actuation stage recently have been proposed for fine control of a position of a read/write head with respect to a hard disk to be read or written.
FIGS. 1 and 2
schematically show an example of a known hard disk actuating device
1
with a dual actuation stage. Shown in detail in
FIG. 1
, the hard disk actuation device
1
comprises a motor
2
(also called “voice coil motor”)to which at least one suspension
5
formed by a lamina is fixed in projecting manner. At its free end, the suspension
5
has an R/W (read/write) transducer
6
(see
FIG. 2
) (also called a “slider”)disposed when in an operative condition to face a surface of a hard disk
7
(see FIG.
1
). The R/W transducer
6
is rigidly connected to a coupling (called a “gimbal”
8
), via a microactuator
9
interposed between the gimbal
8
and the R/W transducer
6
. On one of its lateral surfaces, the RIW transducer
6
, formed by a ceramic material body (e.g., AITiC), further has a read/write head
10
(which is magneto/resistive and inductive) that forms the read/write device proper.
In the actuating device
1
, a first actuation stage is formed by the motor
2
that moves a unit including the suspension
5
and the R/W transducer
6
across the hard disk
7
during track seeking. A second actuation stage is formed by the microactuator
9
that finely controls the position of the R/W transducer
6
during tracking.
An embodiment of a microactuator
9
of a rotary electrostatic type is shown in diagrammatic form in
FIG. 3
, with the microactuator
9
shown only in part, given its axial symmetry. The microactuator
9
comprises a stator
17
, which is integral with a die accommodating the microactuator
9
and bonded to the gimbal
8
, and a rotor
11
, intended to be bonded to the R/W transducer
6
and capacitively coupled to the stator
17
.
The rotor
11
comprises a suspended mass
12
of substantially circular shape and a plurality of movable arms
13
extending radially towards the outside from the suspended mass
12
. Each movable arm
13
has a plurality of movable electrodes
14
extending in a substantially circumferential direction and spaced at a same distance from each other. The rotor
11
further comprises anchoring and elastic suspension elements (shown as springs
15
in
FIG. 3
) for supporting and biasing of the rotor
11
through fixed regions
16
.
The stator
17
comprises a plurality of fixed arms
18
a
,
18
b
extending radially inward and each bearing a plurality of fixed electrodes
19
. In particular, associated with each movable arm
13
is a pair of fixed arms formed by a fixed arm
18
a
and a fixed arm
18
b
. Fixed electrodes
19
of each pair of fixed arms
18
a
,
18
b
extend towards an associated movable arm
13
and are intercalated or interleaved with the movable electrodes
14
. The fixed arms
18
a
are all disposed on a same side of the respective movable arms
13
(on the right side in the example shown in
FIG. 3
) and are all polarized at a same potential via biasing regions
20
a
. Similarly the fixed arms
18
b
are all disposed on the other side of the respective movable arms
13
(on the left side in the example shown in
FIG. 3
) and are all biased at a same potential through biasing regions
20
b
. The fixed arms
18
a
and
18
b
are biased at different potentials to generate two different potential differences with respect to the movable arms
13
and cause the rotor
11
to rotate in one direction or the other. The known arrangement shown in
FIG. 2
does, however, have several disadvantages. The microactuator
9
is subject to intense mechanical stresses due to impacts of the RIW transducer
6
against the hard disk
7
that may damage the microactuator
9
. Furthermore, the microactuator
9
is exposed to an external environment, and therefore is not protected from extraneous particles present in the environment that may compromise its satisfactory operation. Also, biasing voltages supplied to the microactuator
9
to obtain desired movements of the R/W transducer
6
have relatively high values (of the order of 80 V) which may cause electrostatic interference in the direction of the R/W transducer
6
.
SUMMARY OF THE INVENTION
An advantage of the present invention is to provide an integrated microactuator which overcomes the disadvantages of the proposed microactuators described above.
Embodiments of the invention provide an integrated microactuator comprising a motor element, the motor element including a stator element and a rotor element coupled reciprocally thereto. The integrated microactuator further comprises a separate actuator element and a transmission structure interposed between the motor element and the actuator element to transmit a movement of the motor element into a corresponding movement of the actuator element.


REFERENCES:
patent: 3789378 (1974-01-01), Bonzano et al.
patent: 4065677 (1977-12-01), Micheron et al.
patent: 5025346 (1991-06-01), Tang et al.
patent: 5151763 (1992-09-01), Marek et al.
patent: 5216631 (1993-06-01), Sliwa, Jr.
patent: 5233213 (1993-08-01), Marek
patent: 5428259 (1995-06-01), Suzuki
patent: 5438469 (1995-08-01), Rudi
patent: 5477097 (1995-12-01), Matsumoto
patent: 5521778 (1996-05-01), Boutaghou et al.
patent: 5631514 (1997-05-01), Garcia et al.
patent: 5657188 (1997-08-01), Jurgenson et al.
patent: 5995334 (1999-11-01), Fan et al.
patent: 0 482 205 (1992-04-01), None
patent: 0 533 095 (1993-03-01), None
patent: 0 578 228 (1994-01-01), None
patent: 0 578 228 (1994-01-01), None
patent: 0 613 124 (1994-08-01), None
patent: 0 840 291 (1998-05-01), None
patent: 07-177773 (1995-07-01), None
patent: WO 93/21536 (1993-10-01), None
patent: WO 95/34943 (1995-12-01), None
Tang et al., “Laterally Driven Polysilicon Resonant Microstructures,”Sensors and Actuators.(20):25-32, Nov. 15, 1989.
Starr, “Squeeze-Film Damping in Solid State Accelerometers,”IEEE Solid-State Sensor an Actuator Workshop, pp. 44-47, Jun. 1990.
Gianchandani et al., “Batch Fabrication and Assembly of Micromotor-Driven Mechanisms With Multi-Level Linkages,”Micro Electro Mechanical Systems, IEEE, pp. 141-146, 1992.
Lee et al., “Polysilicon Micro Vibromotors,”Micro Electro Mechanical Systems, IEEE, pp. 177-182, Feb. 4-7, 1992.
Fujita et al., “Position Control of An Electrostatic Linear Actuator Using Rolling Motion,”Mechatronics, vol. 2, No. 5, pp. 495-502, Oct. 1992.
Zhang et al., “Viscous Air Damping in Laterally Driven Microresonators,”IEEE Workshop No. 7, pp. 199-204, Jan. 25, 1994.
Fan et al., “Magnetic Recording Head Positioning at Very High Track Densities Using a Microactuator-Based, Two-Stage Servo System,”Transactions on Industrial Electronics, IEEE, 42(3):222-233, Jun. 1995.
Moesner et al, “Electrostatic Devices For Particle Micro-Handling,” IEEE, pp. 1302-1309, 1995.
Imamura et al., “Transverse Mode Electrostatic Microactuator For MEMS-Based HDD Slider,”IEEE, pp. 216-221, 1996.
Horsley et al., “Angular Micropositioner For Disk Drives,”IEEE MEMS '97 WorkshopNagoya, Japan.
Veijola et al., “Mode for Gas Film Damping in a Silicon Accelerometer,” 1997International Conference on Solid-State Sensors and Actuators, pp. 1097-1100, Jun. 16-19, 1997.
Pannu et al., “Accelerometer Feedforward Servo For Disk Drives.” Presented at theAdvanced Intelligent Mechatronics-International Conference, Tokyo, Japan, Jun. 1997.
Aggarwal, “Design and Control of Micro-Actuators For High Density Disk Drives,”Thesis Graduate Division—University of California at Berkeley, May 1997.
Aggarwal et al., “Micro-Actuators For High Density Disk Drives,”American Control Conference, 1997.
Peter Mee et al, “Only Clean Drives Are Good Drives,”Data Storage, pp. 77-80, Sep. 1997.

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