Flexure microactuator

Dynamic magnetic information storage or retrieval – Head mounting – For adjusting head position

Reexamination Certificate

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

Reexamination Certificate

active

06222706

ABSTRACT:

BACKGROUND OF THE INVENTION
The present invention relates to a flexure microactuator, and more particularly to a high resolution head positioning mechanism having a piezoelectric element for moving a flexure carrying a slider to selectively move the head on the slider radially with respect to a rotatable disc.
The density, or radial spacing, between concentric data tracks on magnetic discs continues to increase, requiring greater precision in head positioning. Conventionally, head positioning is accomplished by operating an actuator arm with a large-scale actuator motor, such as a voice coil motor, to position a head on a flexure at the end of the actuator arm. The large-scale motor lacks sufficient resolution to effectively accommodate high track-density discs. Thus, a high resolution head positioning mechanism is necessary to accomplish the more densely spaced tracks.
One promising design for high resolution head positioning involves employing a high resolution microactuator in addition to the conventional low resolution actuator motor, thereby effecting head positioning through dual-stage actuation. Various microactuator designs have been considered to accomplish high resolution head positioning. However, these designs all have shortcomings that limit the effectiveness of the microactuator. For example, where the microactuator was implemented directly on the slider, the complexity of slider design was increased and noise generated by the microactuator and by signal paths to it was induced into the head. New fabrication techniques had to be developed to integrate the slider and microactuator into a single structure. Where the microactuator was to be formed by thin-film wafer techniques onto the flexure, the entire flexure assembly had to be redesigned because the microactuator required a silicon substrate support and conventional gimbaling flexures were not constructed of silicon. Where the microactuator was implemented at the head mounting block (where the actuator arm connects to the head suspension load beam), high forces were required from the microactuator to move the mass associated with the head suspension at a speed (frequency) large enough to accommodate rapid track access. If the force was not great enough, the microactuator operated with lower natural frequency than was desirable, and track settling time was sacrificed. Therefore, the prior designs did not present ideal microactuator solutions.
There is a need in the art for a simple microactuator design to provide efficient high resolution head positioning in a dual-stage actuation system, that can be implemented by readily available manufacturing processes.
BRIEF SUMMARY OF THE INVENTION
The present invention is a mechanism for positioning a transducing head with respect to a selected radial track of a rotatable recording disc in a disc drive. The disc drive includes an actuator arm and a suspension load beam connected to the actuator arm. A plate is hingedly attached to the suspension load beam. A flexure is attached to the plate, and a slider supporting the transducing head is attached to the flexure. A microactuator is attached to the plate, and is operable in response to electrical control signals to move the plate relative to the load beam in the general plane of the load beam to selectively radially position the transducing head proximate to the selected track on the rotatable recording disc. In one form of the invention, the hinged attachment between the load beam and the plate is formed by a hinged portion of the load beam, distortable in response to operation of the microactuator to move the plate.


REFERENCES:
patent: 3678482 (1972-07-01), Billawala
patent: 3924268 (1975-12-01), McIntosh et al.
patent: 4374402 (1983-02-01), Blessom et al.
patent: 4605977 (1986-08-01), Matthews
patent: 4620251 (1986-10-01), Gitzendanner
patent: 4651242 (1987-03-01), Hirano et al.
patent: 4724500 (1988-02-01), Dalziel
patent: 4764829 (1988-08-01), Makino
patent: 4853810 (1989-08-01), Pohl et al.
patent: 4914725 (1990-04-01), Belser et al.
patent: 5021906 (1991-06-01), Chang et al.
patent: 5034828 (1991-07-01), Ananth et al.
patent: 5055969 (1991-10-01), Putnam
patent: 5065268 (1991-11-01), Hagen
patent: 5079659 (1992-01-01), Hagen
patent: 5105408 (1992-04-01), Lee et al.
patent: 5177652 (1993-01-01), Yamaguchi et al.
patent: 5189578 (1993-02-01), Mori et al.
patent: 5255016 (1993-10-01), Usui et al.
patent: 5276573 (1994-01-01), Harada et al.
patent: 5303105 (1994-04-01), Jorgenson
patent: 5333085 (1994-07-01), Prentice et al.
patent: 5521778 (1996-05-01), Boutaghou
patent: 5552809 (1996-09-01), Hosono et al.
patent: 5570261 (1996-10-01), Frater et al.
patent: 5623461 (1997-04-01), Sohmuta
patent: 5650894 (1997-07-01), Ikeda
patent: 5657188 (1997-08-01), Jurgenson et al.
patent: 5734526 (1998-03-01), Symons
patent: 5867347 (1999-02-01), Knight et al.
patent: 5898544 (1999-04-01), Krinke et al.
patent: 5936805 (1999-08-01), Imaino
patent: 6069771 (2000-05-01), Boutaghou et al.
patent: 0 412 221 B1 (1989-11-01), None
patent: 63-122069 (1988-05-01), None
patent: 2-263369 (1989-04-01), None
patent: 4-134681 (1992-05-01), None
patent: 4-368676 (1992-12-01), None
patent: 5-094682 (1993-04-01), None
patent: 6-020412 (1994-01-01), None
patent: 7-085621 (1995-03-01), None
“Silicon Micromachined Electromagnetic Microactuators for Rigid Disk Drives” by Tang et al,IEEE Transactions on Magnetics, vol. 31, No. 6, Nov. 1995.
“Magnetic Recording Head Positioning at Very High Track Densities Using a Microactuator-Based, Two-Stage Servo System” by Fan et al.,IEEE Transactions on Industrial Electronics, vol. 42, No. 3, Jun. 1995.
“A Flexural Piggyback Milli-Actuator for Over 5 Gbit/in2Density Magnetic Recording” by Koganezawa et al,IEEE Transactions on Magnetics, vol. 32, No. 5, Sep. 1996.
“Transverse Mode Electrostatic Microactuator for MEMS-Based HDD Slider” by Imamura et al,IEEE1996.
“An Experiment for Head Positioning System Using Submicron Track-width GMR Head” by Yoshikawa et al.,IEEE Transactions on Magnetics, vol. 32, No. 5, Sep. 1996.
“Micro Electrostatic Actuators in Dual-Stage Disk Drives with High Track Density” by Tang et al.,IEEE Transactions on Magnetics, vol. 32, No. 5, Sep. 1996.
“Piezoelectric Microactuator Compensating for Off-Track Errors in Magnetic Disk Drives” by Imamura et al,Advance Information Storage Systems, vol. 5, pp 119-125.
“A Dual-Stage Magnetic Disk Drive Actuator Using a Piezoelectric Device for a High Track Density” by Mori et al.,IEEE Transactions on Magnetics, vol. 27, No. 6, Nov. 1991.
“Dynamic Loading Criteria for 3½ Inch Inline HDD Using Multilayer Piezoelectric Load/Unload Mechanism” by Kajitani et al.,IEEE Transactions on Magnetics, vol. 27, No. 6, Nov. 1991.
“Design, Fabrication, and Testing of Silicon Microgimbals for Super-Compact Rigid Disk Drives” by Temesvary et al.,Journal of Microelectromechanical Systems, vol. 4, N.

LandOfFree

Say what you really think

Search LandOfFree.com for the USA inventors and patents. Rate them and share your experience with other people.

Rating

Flexure microactuator does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Flexure microactuator, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Flexure microactuator will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFUS-PAI-O-2523789

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.