Piezoelectric/electrostrictive device

• US 7,345,406 B2
• Filed: 08/17/2005
• Issued: 03/18/2008
• Est. Priority Date: 01/18/2001
• Status: Expired due to Fees

• Current Assignee: NGK Insulators Limited
• Original Assignee: NGK Insulators Limited
• Inventors: Ikeda, Koji, Shibata, Kazuyoshi
• Primary Examiner(s): Dougherty; Thomas M.
• Application Number:
  US11/206,252
• Publication Number:
  US 20060061238A1
• Time in Patent Office: 944 Days
• Field of Search: 310/328, 310/333, 310/348
• US Class Current: 310/333
• CPC Class Codes: G11B 5/5552 using fine positioning means for track acquisition separate from the coarse (e.g. track changing) positioning means
• CPC Class Codes: H10N 30/2043 connected at their free ends, e.g. parallelogram type

Abstract

A piezoelectric/electrostrictive device that includes a base 11 having a pair of right and left movable parts 11a, 11b and a fixing part 11c disposed at one end thereof as well as piezoelectric/electrostrictive elements 12a, 12b disposed on the sides of the movable parts 11a, 11b of the base 11 is fabricated to have a construction with fewer components. The piezoelectric/electrostrictive device having a construction with fewer components is provided by adopting a base 11 having an integral structure formed by bending an original plate stamped into a shape that delineates a plane development of the base, as the base of the piezoelectric/electrostrictive device. In addition, in this piezoelectric/electrostrictive device, piezoelectric/electrostrictive elements are arranged on inner sides of a pair of left and right movable parts. Accordingly, destruction of the piezoelectric/electrostrictive element can hardly occur and high reliability of the piezoelectric/electrostrictive device is achieved.

Claims

1. A piezoelectric/electrostrictive device comprising:

a base being constructed with one sheet of flat plate, the base having a fixing part of a flat plate shape, a mounting part that is separate from the fixing part and having a flat plate shape, and a pair of left and right movable parts, the pair of movable parts each being supported at one end side thereof by each side edge of the fixing part and at the other end side thereof by each side edge of the mounting part, the respective movable parts being erect by a predetermined height from the side edges of the fixing part and the mounting part to face each other and extend along the side edges of the fixing part and the mounting part; and

a piezoelectric/electrostrictive element arranged on an inner side of at least one of the pair of left and right movable parts, a first end of the piezoelectric/electrostrictive element extending to a position on the inner side of the at least one of the pair of left and right movable parts, the position overlapping the side edge of the fixing part,

wherein (i) La is a distance measured along a respective movable part between a boundary of the respective movable part and the fixing part and a boundary of the respective movable part and the mounting part, (ii) Lb is a distance measured along the respective movable part between the boundary of the respective movable part and the mounting part to a second end of the piezoelectric/electrostrictive element opposite the first end, and (iii) a value of the equation (1−

Lb/La) is from 0.5 to 0.8.

2. A piezoelectric/electrostrictive device according to claim 1, wherein a piezoelectric/electrostrictive element is further provided on an outer side of at least one of the pair of left and right movable parts.

3. A piezoelectric/electrostrictive device comprising:

a base being constructed with one sheet of flat plate, the base having a fixing part of a flat plate shape, a mounting part that is separate from the fixing part and having a flat plate shape, a pair of left and right movable parts, the pair of movable parts each being supported at one end side thereof by each side edge of the fixing part and at the other end side thereof by each side edge of the mounting part, the respective movable parts being erect by a predetermined height from side edges of the fixing part and the mounting part to face each other and extend along the side edges of the fixing part and the mounting part, a first receiving part extending from a mid portion between the one end side and the other end side of at least one of the pair of left and right movable parts in parallel with a flat surface of the base, and a second receiving part extending from at least one of the side edges of the fixing part in parallel with the flat surface of the base, and

a piezoelectric/electrostrictive element disposed at one end side thereof on the second receiving part and at the other end side thereof on the first receiving part so as to connect the first receiving part and the second receiving part.