Power generator

Patent metadata

Field	Value
Publication number	US-10312833-B2
Application number	US-201515305314-A
Country	US
Kind code	B2
Filing date	Feb 19, 2015
Priority date	Apr 23, 2014
Publication date	Jun 4, 2019
Grant date	Jun 4, 2019

Abstract

A power generator 1 includes a magnetostrictive rod 2 through which lines of magnetic force pass in an axial direction thereof, a beam member 73 having a function of generating stress in the magnetostrictive rod 2, and a coil 3 arranged so that the lines of magnetic force pass inside the coil 3 in an axial direction of the coil 3. The beam member 73 is arranged along the magnetostrictive rod 2 and configured to allow one end portion and the other end portion of the magnetostrictive rod 2 to approach to each other to generate compressive stress in the magnetostrictive rod 2. Further, in the power generator 1, it is preferable that a gap between the beam member 73 and the magnetostrictive rod 2 on the side of the one end portion of the magnetostrictive rod 2 is larger than a gap between the beam member 73 and the magnetostrictive rod 2 on the side of the other one end portion of the magnetostrictive rod 2 in a side view.

First claim

What is claimed is:

1. A power generator comprising:
a magnetostrictive rod through which lines of magnetic force pass in an axial direction thereof, the magnetostrictive rod formed of a magnetostrictive material;
a coil arranged so that the lines of magnetic force pass inside the coil in an axial direction of the coil whereby a voltage is generated in the coil due to variation of density of the lines of magnetic force; and
a bias stress generating mechanism for generating compressive stress in the magnetostrictive rod in a natural state,
wherein the magnetostrictive rod has one end portion and the other end portion, and
wherein the power generator is configured to generate the voltage in the coil due to the variation of the density of the lines of magnetic force when the other end portion of the magnetostrictive rod is displaced with respect to the one end portion of the magnetostrictive rod in a direction substantially perpendicular to the axial direction of the magnetostrictive rod to expand and contract the magnetostrictive rod, wherein the bias stress generating mechanism includes a beam member which is arranged along the magnetostrictive rod and allows the one end portion and the other end portion of the magnetostrictive rod to approach to each other to generate the compressive stress in the magnetostrictive rod.

2. The power generator as claimed in claim 1 , wherein a gap between the beam member and the magnetostrictive rod on the side of the other end portion of the magnetostrictive rod is smaller than a gap between the beam member and the magnetostrictive rod on the side of the one end portion of the magnetostrictive rod in a side view.

3. The power generator as claimed in claim 1 , wherein the beam member is formed of a non-magnetic material.

4. The power generator as claimed in claim 1 , wherein the magnetostrictive rod includes two or more of magnetostrictive rods arranged side by side, and
wherein the two or more of magnetostrictive rods are arranged so as not to overlap with the beam member in a planar view.

5. The power generator as claimed in claim 4 , wherein the beam member is arranged between the magnetostrictive rods in the planar view.

6. The power generator as claimed in claim 1 , wherein the bias stress generating mechanism further includes a magnetic member provided on the side of the other end portion of the magnetostrictive rod and a magnet for attracting the magnetic member so as to generate the compressive stress in the magnetostrictive rod.

7. The power generator as claimed in claim 1 , further comprising:
a first block body including a receiving portion for receiving the one end portion of the magnetostrictive rod, the first block body formed of a magnetic material; and
a second block body including a receiving portion for receiving the other end portion of the magnetostrictive rod, the second block body formed of a magnetic material.

8. The power generator as claimed in claim 1 , wherein the coil is wound around the magnetostrictive rod.

Assignees

• Mitsumi Electric Co Ltd

Inventors

• Furukawa Kenichi
• Numakunai Takayuki

Classifications

• H01L41/125

  Electricity · mapped topic

• H02K1/34

  Reciprocating, oscillating or vibrating parts of the magnetic circuit · CPC title

• H02K3/28

  Layout of windings or of connections between windings (windings for pole-changing H02K17/06, H02K17/14, H02K19/12, H02K19/32) · CPC title

• H02N2/18 Primary

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

• H10N35/101

  with mechanical input and electrical output, e.g. generators, sensors · CPC title