Piezoelectric actuator and information storage apparatus
AssigneeFujitsu Limited
InventorsKazuaki Kurihara, Masaharu Hida, Tsuyoshi Mita, Shigeyoshi Umemiya, Michinori Kutami
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Abstract
There are disclosed a piezoelectric actuator which can obtain large displacement at low voltage, which is small-sized and lightweight, and whose manufacture cost is low, and a small-sized lightweight information storage apparatus in which the piezoelectric actuator is incorporated, and which is provided with a small inertia moment during head driving and a high recording density. A piezoelectric actuator 200 includes a center body 200a and two spiral arms 200b, and two arms 200b are entirely in rotation symmetry and nonlinear symmetry.
Claims3
A piezoelectric actuator comprising:
- at least one driving portion provided with a lamination structure including at least one piezoelectric layer of a piezoelectric material and a plurality of electrode layers for holding the piezoelectric layer, the lamination structure being compressible and extendible in a thickness direction of the lamination structure;
- and
- a holding portion for holding a plurality of said driving portions in an arrangement of rotation symmetry and nonlinear symmetry in a predetermined common plane.
An information storage apparatus comprising:
- a head portion on which a head for performing at least one of information recording and information reproduction with respect to a predetermined information storage medium is mounted;
- an arm portion for holding the head portion in such a manner that the head mounted on said head portion is disposed in the vicinity of or in contact with said information storage medium;
- an arm portion actuator for driving said arm portion to move the head mounted on the head portion held by the arm portion along said information storage medium;
- and
- a head portion actuator for rotating said head portion with respect to said arm portion and centering on a gravity center of the head portion,
- wherein said head portion actuator comprises:
- at least one driving portion provided with a lamination structure including at least one piezoelectric layer of a piezoelectric material and a plurality of electrode layers for holding the piezoelectric layer, the lamination structure being compressible and extendible in a thickness direction of the lamination structure;
- and
- a holding portion for holding a plurality of said driving portions in an arrangement of rotation symmetry and nonlinear symmetry in a predetermined common plane.
Dependencies are inferred from the claim text.