Piezoelectric/electrostrictive device having mutually opposing end surfaces and method of manufacturing the same

• US 6,498,419 B1
• Filed: 03/13/2000
• Issued: 12/24/2002
• Est. Priority Date: 10/01/1999
• Status: Expired due to Fees

• Current Assignee: NGK Insulators Limited
• Original Assignee: NGK Insulators Limited
• Inventors: Takeuchi, Yukihisa, Kimura, Koji, Ikeda, Koji, Nanataki, Tsutomu, Shibata, Kazuyoshi
• Primary Examiner(s): Patel, Tulsidas
• Assistant Examiner(s): Zarroli, Michael C.
• Application Number:
  US09/524,042
• Time in Patent Office: 1,016 Days
• Field of Search: 310/321, 310/328, 310/330, 310/331, 310/367, 310/368, 735/041.3
• US Class Current: 310/321
• CPC Class Codes: H10N 30/05 Manufacture of multilayered piezoelectric or electrostrictive devices, or parts thereof, e.g. by stacking piezoelectric bodies and electrodes
• CPC Class Codes: H10N 30/204 using bending displacement, e.g. unimorph, bimorph or multimorph cantilever or membrane benders
• CPC Class Codes: H10N 30/2043 connected at their free ends, e.g. parallelogram type
• CPC Class Codes: Y10T 29/42 Piezoelectric device making

Abstract

A piezoelectric/electrostrictive device comprises a pair of mutually opposing thin plate sections, a movable section, and a fixation section for supporting the thin plate sections and the movable section. A piezoelectric/electrostrictive element is arranged on at least one thin plate section of the pair of thin plate sections. A hole is formed by the inner walls of the pair of thin plate sections, the movable section and the fixation section. A central portion of the movable section is cut off to form mutually opposing end surfaces in the movable section.

Claims

1. A piezoelectric/electrostrictive device comprising:

a pair of mutually opposing thin plate sections, each lying in its own respective plane with the two planes being parallel to one another, a movable section, and a fixation section for supporting said thin plate sections and said movable section;

one or more piezoelectric/electrostrictive elements arranged on at least one thin plate section of said pair of thin plate sections and extending onto one of said fixation section and said movable section; and

a hole formed by both inner walls of said pair of thin plate sections, an inner wall of said movable section, and an inner wall of said fixation section, wherein;

any one of said movable section and said fixation section has mutually opposing end surfaces.

2. The piezoelectric/electrostrictive device according to claim 1, wherein:

a cutoff section is provided on any one of said movable section and said fixation section; and

a part of said cutoff section constitutes said mutually opposing end surfaces.

3. The piezoelectric/electrostrictive device according to claim 1, wherein said thin plate section, said movable section, and said fixation section are composed of a ceramic substrate integrated into one unit by simultaneously sintering a ceramic green stack and cutting off unnecessary portions.

4. The piezoelectric/electrostrictive device according to claim 3, wherein said piezoelectric/electrostrictive element has a film-shaped configuration, and it is integrated with said ceramic substrate by means of sintering.

5. The piezoelectric/electrostrictive device according to claim 1, wherein a gap is formed between said mutually opposing end surfaces.

6. The piezoelectric/electrostrictive device according to claim 1, wherein said device has such a structure that internal residual stress, which has been generated in said thin plate section and/or said piezoelectric/electrostrictive element during production, is released by forming said mutually opposing end surfaces.

7. 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.

8. A piezoelectric/electrostrictive device comprising:

a pair of mutually opposing thin plate sections, a movable section, and a fixation section for supporting said thin plate sections and said movable section;

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

a hole formed by both inner walls of said pair of thin plate sections, an inner wall of said movable section, and an inner wall of said fixation section, wherein;

any one of said movable section and said fixation section has mutually opposing end surfaces; and

a member, which is different from a constitutive member of any one of said movable section and said fixation section, is interposed between said mutually opposing end surfaces.

9. The piezoelectric/electrostrictive device according to claim 8, wherein said member is organic resin.

10. A piezoelectric/electrostrictive device comprising:

a pair of mutually opposing thin plate sections, a movable section, and a fixation section for supporting said thin plate sections and said movable section;

one or more piezoelectric/electrostrictive elements arranged on at least one thin plate section of said pair of thin plate sections, said piezoelectric/electrostrictive element including a piezoelectric/electrostrictive layer and a pair of electrodes formed on said piezoelectric/electrostrictive layer, 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; and

a hole formed by both inner walls of said pair of thin plate sections, an inner wall of said movable section, and an inner wall of said fixation section, wherein;

any one of said movable section and said fixation section has mutually opposing end surfaces.

11. A piezoelectric/electrostrictive device comprising:

a pair of mutually opposing thin plate sections, each lying in its own respective plane with the two planes being parallel to one another, a movable section, and a fixation section for supporting said thin plate sections and said movable section;

one or more piezoelectric/electrostrictive elements arranged on at least one thin plate section of said pair of thin plate sections and extending onto one of said fixation section and said movable section, wherein said piezoelectric/electrostrictive element has a piezoelectric/electrostrictive layer and a pair of electrodes formed on both sides of said piezoelectric/electrostrictive layer, and one electrode of said pair of electrodes is formed on at least said thin plate section; and

a hole formed by both inner walls of said pair of thin plate sections, an inner wall of said movable section, and an inner wall of said fixation section, wherein;

any one of said movable section and said fixation section has mutually opposing end surfaces.

12. A piezoelectric/electrostrictive device comprising:

a pair of mutually opposing thin plate sections, a movable section, and a fixation section for supporting said thin plate sections and said movable section;

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

a hole formed by both inner walls of said pair of thin plate sections, an inner wall of said movable section, and an inner wall of said fixation section; and

a gel material filling said hole, wherein;

any one of said movable section and said fixation section has mutually opposing end surfaces.