US 11,716,033 B2
Vibration-driven energy harvesting element and vibration-driven energy harvesting device
Hiroshi Toshiyoshi, Tokyo (JP); Hisayuki Ashizawa, Sayama (JP); and Masahiro Morita, Sayama (JP)
Assigned to The University of Tokyo, Tokyo (JP); and Saginomiya Seisakusho, Inc., Tokyo (JP)
Appl. No. 17/53,598
Filed by The University of Tokyo, Tokyo (JP); and SAGINOMIYA SEISAKUSHO, INC., Tokyo (JP)
PCT Filed Apr. 19, 2019, PCT No. PCT/JP2019/016865
§ 371(c)(1), (2) Date Nov. 6, 2020,
PCT Pub. No. WO2019/216165, PCT Pub. Date Nov. 14, 2019.
Claims priority of application No. 2018-090196 (JP), filed on May 8, 2018.
Prior Publication US 2021/0234478 A1, Jul. 29, 2021
Int. Cl. H02N 1/08 (2006.01); B81B 3/00 (2006.01)
CPC H02N 1/08 (2013.01) [B81B 3/0086 (2013.01); B81B 2203/0163 (2013.01)] 10 Claims
OG exemplary drawing
 
1. A vibration-driven energy harvesting element that outputs an alternating current power from output lines of the vibration-driven energy harvesting element, due to vibration from outside, comprising:
an intermediate electrode that is not connected to the output lines of the vibration-driven energy harvesting element;
a plurality of electret electrodes, each electret electrode being arranged to face the intermediate electrode and having an electret on at least a part of a surface of the electret electrode on a side facing the intermediate electrode;
a holding unit that holds the intermediate electrode and the plurality of electret electrodes such that the intermediate electrode and the plurality of electret electrodes can vibrate with respect to each other;
a circuit powered from the vibration-driven energy harvesting element; and
a charge injector that injects a charge having characteristics opposite to a charge of the electrets formed in the surfaces of the plurality of electret electrodes, to the intermediate electrode and connects the intermediate electrode to the circuit powered from the vibration-driven energy harvesting element,
wherein each of the plurality of electret electrodes has an output connected to a respective input of the circuit powered from the vibration-driven energy harvesting.