Piezoelectric/electrostrictive device and method of manufacturing same

• US 6,448,693 B1
• Filed: 09/25/2000
• Issued: 09/10/2002
• 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, Nanataki, Tsutomu
• Primary Examiner(s): Dougherty, Thomas M.
• Application Number:
  US09/669,441
• Time in Patent Office: 715 Days
• Field of Search: 310/328, 310/330, 310/344, 310/331
• US Class Current: 310/328
• 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 29/49789 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 fixing section for supporting the thin plate sections and the movable section. Piezoelectric/electrostrictive elements are arranged on at least one thin plate section of 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 fixing section. The piezoelectric/electrostrictive device further includes at least one beam section extending from the inner wall of the movable section to the inner wall of the fixing section.

Claims

1. A piezoelectric/electrostrictive device having a pair of mutually opposing thin plate sections, a movable section, and a fixing section for supporting said thin plate sections and said movable section, said piezoelectric/electrostrictive device comprising:

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 fixing section, wherein

at least one beam section is provided extending from said inner wall of said movable section to said inner wall of said fixing section.

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

surfaces of said thin plate sections, on which said piezoelectric/electrostrictive elements are formed, are designated as side surfaces of said thin plate sections, and a width of said side surfaces of said thin plate sections in the minor side direction is designated as the width of said thin plate sections, wherein

a width of said beam section is at least ⅕ of said width of said thin plate sections.

3. A piezoelectric/electrostrictive device according to claim 1, wherein

surfaces of said thin plate sections, on which said piezoelectric/electrostrictive elements are formed, are designated as side surfaces of said thin plate sections, and

a length of said side surfaces of said thin plate sections in the major side direction is designated as a length Le of said thin plate sections, wherein

a ratio (Le/Tb) of said length Le of said thin plate sections to a total thickness Tb of said beam section is from 5 to 200.

4. A piezoelectric/electrostrictive device according to claim 1, wherein

said thin plate sections, said movable section and said fixing section comprise an integrated ceramic substrate formed by co-firing a ceramic green laminate, followed by cutting off unnecessary portions.

5. A piezoelectric/electrostrictive device according to claim 4, wherein

said piezoelectric/electrostrictive elements are of a film form and integrated with said ceramic substrate by firing.

6. A piezoelectric/electrostrictive device according to claim 1, wherein

said piezoelectric/electrostrictive elements have a piezoelectric/electrostrictive layer and a pair of electrodes formed on said piezoelectric/electrostrictive layer.

7. A piezoelectric/electrostrictive device according to claim 6, wherein

said piezoelectric/electrostrictive elements are constructed by laminating a plurality of said piezoelectric/electrostrictive layers and said pair of electrodes.

8. A piezoelectric/electrostrictive device according to claim 1, wherein

said hole is filled with a gel-like material.