Claims
- 1. A matrix type actuator as a piezoelectric/electrostrictive actuator in which a plurality of piezoelectric/electrostrictive elements each consisting of a piezoelectric/electrostrictive body and at least one pair of electrodes are formed on a thick ceramic substrate, said actuator being activated by the displacement of said piezoelectric/electrostrictive bodies,
characterized in that said piezoelectric/electrostrictive elements are joined to said ceramic substrate into respective unified bodies, and are two-dimensionally arranged independently of each other.
- 2. A matrix type actuator according to claim 1, wherein said electrodes are formed on the side surfaces of said piezoelectric/electrostrictive bodies disposed on said ceramic substrate in said piezoelectric/electrostrictive elements.
- 3. A matrix type actuator according to claim 2, wherein said piezoelectric/electrostrictive elements are expanded/contracted vertically to the main surface of said ceramic substrate in the displacement of said piezoelectric/electrostrictive bodies due to a transverse effect of an electric field induced strain.
- 4. A matrix type actuator according to claim 2, wherein conditions of crystal grains in the wall surfaces of the piezoelectric/electrostrictive bodies of said piezoelectric/electrostrictive elements, where said electrodes are formed on the wall surfaces, is that the crystal grains suffering a transgranular fracture is less than 1%.
- 5. A matrix type actuator according to claim 2, wherein the degree of profile for the surfaces of the piezoelectric/electrostrictive bodies in said piezoelectric/electrostrictive elements is approximately 8 μm or less.
- 6. A matrix type actuator according to claim 2, wherein the surface roughness Rt of the wall surfaces of the piezoelectric/electrostrictive bodies in said piezoelectric/electrostrictive element is approximately 10 μm or less.
- 7. A matrix type actuator according to claim 1, wherein said piezoelectric/electrostrictive elements are formed on said ceramic substrate by alternately laminating a plurality of stratiform piezoelectric/electrostrictive bodies, and a plurality of stratiform electrodes.
- 8. A matrix type actuator according to claim 7, wherein said piezoelectric/electrostrictive elements are expanded/contracted vertically to main surface of said ceramic substrate in displacement of said piezoelectric/electrostrictive bodies due to a longitudinal effect of the electric field induced strain.
- 9. A matrix type actuator according to claim 7, wherein a thickness per layer of said piezoelectric/electrostrictive body in said piezoelectric/electrostrictive elements is 100 μm or less.
- 10. A matrix type actuator according to claim 7, wherein number of layers being composed of said piezoelectric/electrostrictive body in said piezoelectric/electrostrictive element is 10 to 100.
- 11. A matrix type actuator according to claim 1, wherein said piezoelectric/electrostrictive body is formed of a material selected from the group consisting of piezoelectric ceramics, electrostrictive ceramics, and antiferroelectric ceramics and a composite material of at least one of said ceramic materials and a piezoelectric polymer.
- 12. A matrix type actuator according to claim 1, wherein said ceramic substrate and said piezoelectric/electrostrictive elements are made of same material.
- 13. A matrix type actuator according to claim 1, wherein electrode terminals are disposed on the surface opposite to the surface on which said piezoelectric/electrostrictive elements are arranged in said ceramic substrate, and said electrodes and said electrode terminals are wired to each other via through holes or via holes formed in said ceramic substrate.
- 14. A method for manufacturing a matrix type actuator, in which a plurality of piezoelectric/electrostrictive elements consisting of a piezoelectric/electrostrictive body and at least one pair of electrodes are two-dimensionally arranged on a thick ceramic substrate; characterized in that said method comprising:
a step A for obtaining ceramic green lamination structure having through apertures, wherein a plurality of ceramic green sheets including piezoelectric/electrostrictive material as a main component are prepared, said ceramic green sheets are machined with a punch and a die to form apertures at predetermined positions and laminated, and thus the through apertures are formed by connecting said apertures to each other; a step B for preparing ceramic green substrates forming a ceramic substrate; a step C for obtaining a sintered lamination structure by laminating said ceramic green lamination structure and said ceramic green substrate and then by sintering and unifying them; and a step D for slicing said sintered lamination structure at the portion corresponding to the ceramic green lamination structure obtained at least said step A; said method further comprises a process for forming a plurality of independent piezoelectric/electrostrictive elements on the ceramic substrate.
- 15. A method for manufacturing a matrix type actuator according to claim 14, wherein said step A includes,
a first substep for forming first apertures in a first ceramic green sheet with said punch, a second substep for raising said first ceramic green sheet in contact with a stripper in the state of not withdrawing said punch from said first aperture, a third substep for raising said punch in such a manner that the front ends of said punch are withdrawn slightly from the lowest part of said first green sheet raised, a fourth substep for forming second apertures in a second ceramic green sheet with said punch, a fifth substep for raising said second green sheet together with said first ceramic green sheet, and a sixth substep for raising said punch in such a manner that the front ends of said punch are withdrawn slightly from the lowest part of said second ceramic green sheet, whereby the lamination is carried out by repeating the fourth substep to sixth substep, and then the ceramic green lamination structure having through apertures formed by the connection of the apertures can be obtained.
- 16. A method for manufacturing a matrix type actuator according to claim 14, wherein further a step for filling the through apertures of said sintered lamination structure at the portion corresponding to said ceramic green lamination structure with a filler is interposed between said step C and said step D.
Priority Claims (3)
Number |
Date |
Country |
Kind |
2000-391715 |
Dec 2000 |
JP |
|
2001-108986 |
Apr 2001 |
JP |
|
2001-189718 |
Jun 2001 |
JP |
|
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation in part of U.S. patent application Ser. No. 09/900,742 filed on Jul. 6, 2001.
Continuation in Parts (1)
|
Number |
Date |
Country |
Parent |
09900742 |
Jul 2001 |
US |
Child |
09952483 |
Sep 2001 |
US |