Piezoelectric/electrostrictive device and method of manufacturing same

• US 20040017133A1
• Filed: 05/30/2003
• Published: 01/29/2004
• Est. Priority Date: 10/01/1999
• Status: Abandoned Application

• Current Assignee: NGK Insulators Limited
• Original Assignee: NGK Insulators Limited
• Inventors: Nanataki, Tsutomu, Ikeda, Koji, Kimura, Koji, Takeuchi, Yukihisa, Shibata, Kazuyoshi
• Application Number:
  US10/448,984
• Publication Number:
  US 20040017133A1
• Time in Patent Office: Days
• US Class Current: 310/320
• CPC Class Codes: H10N 30/053 by integrally sintering piezoelectric or electrostrictive bodies and electrodes
• CPC Class Codes: H10N 30/2042 Cantilevers, i.e. having one fixed end
• CPC Class Codes: H10N 30/2043 connected at their free ends, e.g. parallelogram type
• CPC Class Codes: H10N 30/302 Sensors
• CPC Class Codes: H10N 30/501 having a non-rectangular cross-section in a plane parallel to the stacking direction, e.g. polygonal or trapezoidal in side view

Abstract

A piezoelectric/electrostrictive device including a pair of mutually opposing thin plate sections and a fixation section for supporting the thin plate sections. A piezoelectric/electrostrictive element is arranged on each of the pair of thin plate sections. Movable sections, having mutually opposing end surfaces, are formed proximate the ends of the thin plate sections. A distance between the end surfaces is not less than a length of the movable sections.

Claims

1. A piezoelectric/electrostrictive device comprising:

a pair of mutually opposing thin plate sections;

a fixation section for supporting said thin plate sections;

movable sections provided at first end portions of said pair of thin plate sections; and

one or more piezoelectric/electrostrictive elements arranged on at least one thin plate section of said pair of thin plate sections, wherein

said movable sections are formed from a material which is different from the material of said thin plate sections.

2. The piezoelectric/electrostrictive device according to claim 1, wherein said movable sections comprise an adhesive member provided between said first end portions of said pair of thin plate sections.

3. The piezoelectric/electrostrictive device according to claim 1, wherein said movable sections include mutually opposing surfaces.

4. The piezoelectric/electrostrictive device according to claim 3, wherein a gap is formed between said mutually opposing surfaces of said movable sections.

5. The piezoelectric/electrostrictive device according to claim 1, wherein said first end portions of said pair of thin plate sections have mutually opposing end surfaces;

and

a distance (Lc) between said mutually opposing end surfaces is not less than a length (Df) of said first end portions of said thin plate sections.

6. The piezoelectric/electrostrictive device according to claim 1, wherein said thin plate sections and said fixation section are composed of a ceramic substrate integrated into one unit by co-firing a ceramic green laminate and cutting off unnecessary portions.

7. The piezoelectric/electrostrictive device according to claim 6, wherein said piezoelectric/electrostrictive element has a film-shaped configuration, and is integrated with said ceramic substrate by means of sintering.

8. The piezoelectric/electrostrictive device according to claim 5, wherein a gap is formed between said mutually opposing end surfaces of said first end portions of said pair of thin plate sections.

9. The piezoelectric/electrostrictive device according to claim 4, further comprising a member having substantially the same composition as a constitutive member of said movable sections, or a plurality of members which are compositionally different therefrom, interposed between said mutually opposing end surfaces of said movable sections, and an area of a surface of said member opposed to said mutually opposing end surfaces is substantially the same as an area of said mutually opposing end surfaces.

10. The piezoelectric/electrostrictive device according to claim 5, wherein said device has such a structure that internal residual stress, which has been generated in at least one of said thin plate sections and said piezoelectric/electrostrictive element during production, is released by forming said mutually opposing end surfaces of said first end portions of said thin plate sections.

11. The piezoelectric/electrostrictive device according to claim 1, wherein said piezoelectric/electrostrictive element has a piezoelectric/electrostrictive layer and a pair of electrodes formed on said piezoelectric/electrostrictive layer.

12. The piezoelectric/electrostrictive device according to claim 11, wherein said piezoelectric/electrostrictive element is constructed in a stacked form comprising a plurality of units each including said piezoelectric/electrostrictive layer and said pair of electrodes.

13. A piezoelectric/electrostrictive device according to claim 9, further comprising a hole formed by both inner walls of said pair of thin plate sections, inner walls of said movable sections, inner walls of said plurality of members and an inner wall of said fixation section, and said hole is filled with a gel material.