Laser machining of electroactive ceramics

• US 7,205,707 B2
• Filed: 05/26/2005
• Issued: 04/17/2007
• Est. Priority Date: 03/09/1999
• Status: Expired due to Term

• Current Assignee: Mide Technology Corporation (Totalenergies Se)
• Original Assignee: Mide Technology Corporation (Totalenergies Se)
• Inventors: Masters, Brett P., Rodgers, John P., van Schoor, Marthinus C.
• Primary Examiner(s): Dougherty; Thomas M.
• Application Number:
  US11/138,803
• Publication Number:
  US 20060006769A1
• Time in Patent Office: 691 Days
• Field of Search: 310330-332, 310367-369, 310/371
• US Class Current: 310/367
• CPC Class Codes: H10N 30/085 by machining
• CPC Class Codes: H10N 30/097 by sintering
• CPC Class Codes: H10N 30/204 using bending displacement, e.g. unimorph, bimorph or multimorph cantilever or membrane benders

Abstract

Laser beam machining is applied to form arbitrarily shaped electroactive ceramics for transducers (e.g., electromechanical sensors and actuators). One particularly preferred embodiment of the invention comprises machining parallel grooves in a ceramic plate to improve flexibility. The grooves provide strain relief in bending by relieving Poisson strains transverse to the direction of bending. This embodiment offers the further benefit that planar anisotropy or directionality is introduced in the transducer. The machining process of the invention further enables the production of more complex geometries than those currently known in the art. Because of the flexibility of the machining process, virtually any desired transducer shape may be produced.

Claims

1. An electromechanical device, comprising

a substantially planar ceramic electroactive member having grooves defined on a planar surface of the member and defining ridges therebetween, whereby the grooves are adapted and constructed to reduce transverse strains generated by bending such that the member is capable of bending to conform to a curved surface while maintaining electrical connections between adjacent ridges.

2. The electromechanical device of claim 1, wherein the device is an electromechanical sensor or actuator.

3. The electromechanical device of claim 1, wherein the device can conform to a curved surface having a radius of curvature no greater than 0.25″

.

4. The electromechanical device of claim 1, wherein the grooves are substantially parallel and the member can conform to a cylindrical surface.

5. The electromechanical device of claim 1, wherein the grooves are substantially concentric and the member can conform to a spherical surface.