Piezoelectric energy harvester having planform-tapered interdigitated beams

United States Patent

May 24, 2011
View the Complete Patent at the US Patent & Trademark Office
Vibrational Energy Converters
Embodiments of energy harvesters have a plurality of piezoelectric planform-tapered, interdigitated cantilevered beams anchored to a common frame. The plurality of beams can be arranged as two or more sets of beams with each set sharing a common sense mass affixed to their free ends. Each set thus defined being capable of motion independent of any other set of beams. Each beam can comprise a unimorph or bimorph piezoelectric configuration bonded to a conductive or non-conductive supporting layer and provided with electrical contacts to the active piezoelectric elements for collecting strain induced charge (i.e. energy). The beams are planform tapered along the entirety or a portion of their length thereby increasing the effective stress level and power output of each piezoelectric element, and are interdigitated by sets to increase the power output per unit volume of a harvester thus produced.
Kellogg; Rick A. (Tijeras, NM), Sumali; Hartono (Albuquerque, NM)
Sandia Corporation (Albuquerque, NM)
December 1, 2008
310/339 ; 310/329;
H01L 41/113 (20060101);
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT The United States Government has certain rights in this invention pursuant to Department of Energy Contract No. DE-AC04-94AL85000 with Sandia Corporation.