Piezoelectric/electrostrictive device and method of manufacturing same

• US 6,883,215 B2
• Filed: 11/05/2003
• Issued: 04/26/2005
• Est. Priority Date: 10/01/1999
• Status: Expired due to Fees

• Current Assignee: NGK Insulators Limited
• Original Assignee: NGK Insulators Limited
• Inventors: Kimura, Koji, Takeuchi, Yukihisa, Nanataki, Tsutomu
• Primary Examiner(s): Tugbang, A. Dexter
• Assistant Examiner(s): Nguyen, Tai Van
• Application Number:
  US10/702,391
• Publication Number:
  US 20040091608A1
• Time in Patent Office: 538 Days
• Field of Search: 29/253.5, 295/94, 298/30, 298/31, 294/17, 294/12, 298/962.2, 310/324, 310/328, 310/358
• US Class Current: 29/25.35
• 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 30/2043 connected at their free ends, e.g. parallelogram type
• CPC Class Codes: Y10T 29/42 Piezoelectric device making
• CPC Class Codes: Y10T 29/49005 Acoustic transducer
• CPC Class Codes: Y10T 29/49126 Assembling bases
• CPC Class Codes: Y10T 29/49128 Assembling formed circuit to base
• CPC Class Codes: Y10T 29/49574 Musical instrument or tuning fork making
• CPC Class Codes: Y10T 29/49789 Obtaining plural product pieces from unitary workpiece
• CPC Class Codes: Y10T 29/49798 Dividing sequentially from leading end, e.g., by cutting or breaking

Abstract

A piezoelectric/electrostrictive device includes 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. One or more piezoelectric/electrostrictive elements are arranged on the pair of thin plate sections. A hole is formed by both inner walls of the pair of thin plate sections, an inner wall of the movable section, and an inner wall of the fixation section. At least one thin plate section of the pair of thin plate sections is previously bent in a direction to make mutual approach so that it has an inwardly convex configuration to the hole.

Claims

1. A method for producing 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, said method comprising the steps of;

producing a ceramic substrate having said thin plate sections and said hole;

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

cutting off a predetermined portion after forming said piezoelectric/electrostrictive element on at least said thin plate section to produce said piezoelectric/electrostrictive device in which at least one thin plate section of said pair of thin plate sections is previously bent in a direction to make mutual approach.

2. A method for producing 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, said method comprising the step of;

cutting off a predetermined portion after forming said piezoelectric/electrostrictive element on at least said thin plate section to produce said piezoelectric/electrostrictive device in which at least one thin plate section of said pair of thin plate sections is previously bent in a direction to make mutual approach.

3. A method for producing 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, said method comprising the step of;

cutting off a predetermined portion after forming said piezoelectric/electrostrictive element on at least said thin plate section to produce said piezoelectric/electrostrictive device in which said pair of thin plate sections are previously bent in directions to make mutual approach.

4. A method for producing 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, said method comprising the steps of;

integrally sintering a ceramic green laminate including at least a first ceramic green sheet having a window for forming at least said hole and second ceramic green sheets to be formed into said thin plate sections to produce a ceramic laminate including portions to be formed into said thin plate sections denting inwardly;

forming said piezoelectric/electrostrictive element on at least an outer surface of a portion of said ceramic laminate to be formed into said thin plate section; and

producing a ceramic substrate formed with at least said piezoelectric/electrostrictive element in which said pair of thin plate sections are bent in directions to make mutual approach, by means of at least a one time cutoff treatment of at least a portion of said ceramic laminate formed with said piezoelectric/electrostrictive element.

5. The method for producing said piezoelectric/electrostrictive device according to claim 4, wherein said first and second ceramic green sheets have a difference in sintering shrinkage speed and/or sintering shrinkage amount.

6. The method for producing said piezoelectric/electrostrictive device according to claim 4, wherein:

said step of forming said piezoelectric/electrostrictive element is performed in accordance with a film formation method; and

at least any one of a pair of electrodes and/or a piezoelectric/electrostrictive layer is integrated by sintering with at least said outer surface of said portion to be formed into said thin plate section.

7. The method for producing said piezoelectric/electrostrictive device according to claim 4, further comprising the step of exposing said hole by means of a cutoff treatment of at least a portion of said ceramic laminate.