Power generator

Patent metadata

Field	Value
Publication number	US-9780281-B2
Application number	US-201414322099-A
Country	US
Kind code	B2
Filing date	Jul 2, 2014
Priority date	Jan 5, 2012
Publication date	Oct 3, 2017
Grant date	Oct 3, 2017

Abstract

A power generator includes layered-polymer piezoelectric element that is arranged on an object to be a heat source and a vibration source, and that generates electric power according to vibration transmitted from the object; a first heat conductor containing a flexible material that is arranged on the object, and that conducts heat from the object. The power generator includes a second heat conductor that is arranged on the first heat conductor and the layered-polymer piezoelectric element, and that conducts heat from the first heat conductor. Furthermore, the power generator includes a thermoelectric element that is arranged on the second heat conductor so as to be layered on the second heat conductor on the layered-polymer piezoelectric element, and that generates electric power according to inner temperature difference between temperature on a heat absorbing side obtained by the second heat conductor and temperature on a heat releasing side.

First claim

What is claimed is:

1. A power generator comprising:
a vibration conversion element that is arranged on an object to be a heat source and a vibration source, and that generates electric power according to vibration transmitted from the object;
a heat conductor that is arranged on the object, and that conducts heat from the object; and
a thermoelectric conversion element that is arranged so as to be layered on a mounting surface of the vibration conversion element on an opposite side to a mounting surface on a side of the object, and that generates electric power according to inner temperature difference between temperature on a heat absorbing side obtained by heat conduction of the heat conductor and temperature on a heat releasing side.

2. The power generator according to claim 1 , wherein
the heat conductor includes
a first heat conductor that is arranged on the object, and that includes a flexible part that conducts heat from the object; and
a second heat conductor that is arranged on a mounting surface of the first heat conductor on an opposite side to a mounting surface on a side of the object, and is arranged between the vibration conversion element and the thermoelectric conversion element, and that conducts heat from the first heat conductor to the thermoelectric conversion element.

3. The power generator according to claim 1 , wherein
a resonance frequency of the power generator is set lower than a vibration frequency of the object.

4. The power generator according to claim 3 , wherein
a resonance frequency of the vibration conversion element is set lower than a resonance frequency of the thermoelectric conversion element.

5. The power generator according to claim 1 , further comprising
a heat releasing unit that is arranged on a mounting surface of the thermoelectric conversion element on an opposite side to a mounting surface on a side of the vibration conversion element, and that releases heat of the thermoelectric conversion element and applies pressure to the vibration conversion element toward a side of the object through the thermoelectric conversion element.

6. The power generator according to claim 1 , wherein
the vibration conversion element is a layered piezoelectric element that uses a polymer piezoelectric material.

7. The power generator according to claim 1 , wherein
the vibration conversion element is any one of a moonie piezoelectric element and a cymbal piezoelectric element.

8. The power generator according to claim 1 , wherein
the thermoelectric element has a structure that n-type semiconductors and p-type semiconductors are alternately arranged and connected in series.

9. The power generator according to claim 2 , wherein
the first heat conductor is any one of
a complex of a conductive material and a flexible material, the conductive material being any one of metal and ceramic, the flexible material being synthetic resin;
an aggregate of any one of metallic fibers and ceramic fibers; and
a metallic spring.

Assignees

• Fujitsu Ltd

Inventors

• Kurihara Kazuaki

Classifications

• H02N2/18

  producing electrical output from mechanical input, e.g. generators (for measurement devices G01) · CPC title

• H01L41/1138

  Electricity · mapped topic

• H02N2/186 Primary

  Vibration harvesters · CPC title

• H01L41/083

  Electricity · mapped topic

• H01L35/32 Primary

  Electricity · mapped topic