U.S. patent application number 10/964934 was filed with the patent office on 2005-05-05 for magnetostriction device.
Invention is credited to Ohashi, Yoshio, Uryu, Masaru.
Application Number | 20050092131 10/964934 |
Document ID | / |
Family ID | 34420177 |
Filed Date | 2005-05-05 |
United States Patent
Application |
20050092131 |
Kind Code |
A1 |
Ohashi, Yoshio ; et
al. |
May 5, 2005 |
Magnetostriction device
Abstract
A magnetostriction device is made such that an impregnated
composition material, such as phenol resin, a resin in which an
inorganic material such as silica is dispersed into a phenol resin,
an epoxy based resins or an acrylic resin is impregnated and caked
into holes of a magnetostrictive sintered material manufactured by
a powder metallurgy method. This magnetostriction device has
improved mechanical strength against an external force.
Inventors: |
Ohashi, Yoshio; (Kanagawa,
JP) ; Uryu, Masaru; (Chiba, JP) |
Correspondence
Address: |
Jay H. Maili
Cooper & Dunham LLP
1185 Avenue of the Americas
New York
NY
10036
US
|
Family ID: |
34420177 |
Appl. No.: |
10/964934 |
Filed: |
October 14, 2004 |
Current U.S.
Class: |
75/246 ;
148/301 |
Current CPC
Class: |
H01L 41/20 20130101 |
Class at
Publication: |
075/246 ;
148/301 |
International
Class: |
H01F 001/08 |
Foreign Application Data
Date |
Code |
Application Number |
Oct 29, 2003 |
JP |
P2003-369396 |
Claims
1. A magnetostriction device comprising an impregnated composition
material impregnated into and caked into holes of a
magnetostrictive sintered material manufactured by a powder
metallurgy method.
2. A magnetostriction device comprising a magnetostrictive sintered
material of Tb.sub.0.3Dy.sub.0.7Fe.sub.2 made of powder ground from
Fe.sub.2Tb, Fe.sub.2Dy by a powder metallurgy method, and an
impregnated composition material being impregnated and caked into
holes of said magnetostrictive sintered material.
3. the magnetostriction device according to claim 1 or 2, wherein
said impregnated composition material is one of phenol resin, a
resin in which an inorganic material such as silica is dispersed
into a phenol resin, an epoxy based resin, and an acrylic
resin.
4. A magnetostriction device according to claim 1 or 2, wherein
said impregnated composition material has a powder-like material
with a high magnetic permeability dispersed thereto.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a magnetostriction device
for use with a magneto-machine transducer device such as a
magnetostriction actuator and a magnetostriction piezoelectric
transducer.
[0003] 2. Description of the Related Art
[0004] The magnetostriction device using the magnetostrictive
sintered material manufactured by the powder metallurgy method has
a small volume density of approximately 80% as compared with a
magnetostriction device manufactured by a single crystal method of
a unidirectional solidification method. The reason for this is that
this magnetostrictive sintered material has holes formed thereon
and that these holes occupy approximately 20% of the whole volume
of the magnetostrictive sintered material.
[0005] Therefore, the magnetostriction device using this
magnetostrictive sintered material has a magnetic permeability
smaller than that of the magnetostriction device manufactured by
this single crystal method or the unidirectional solidification
method. Furthermore, the above magnetostriction device using this
magnetostrictive sintered material encounters with a disadvantage
that it is weak against external force such as when it is easily
broken with application of pre-stress.
SUMMARY OF THE INVENTION
[0006] In view of the aforesaid aspect, it is an object of the
present invention to provide a magnetostriction device in which
mechanical strength against external force can be improved.
[0007] It is another object of the present invention to provide a
magnetostriction device in which a magnetic permeability can be
improved.
[0008] According to an aspect of the present invention, there is
provided a magnetostriction device in which an impregnated
composition material is impregnated into and caked into holes of a
magnetostrictive sintered material manufactured by a powder
metallurgy method.
[0009] According to other aspect of the present invention, there is
provided a magnetostriction device in which a magnetostrictive
sintered material of Tb.sub.0.3Dy.sub.0.7Fe.sub.2 is made of powder
ground from Fe.sub.2Tb, Fe.sub.2Dy by a powder metallurgy method,
an impregnated composition material being impregnated and caked
into holes of the magnetostrictive sintered material.
[0010] According to a further aspect of the present invention,
there is provided a magnetostriction device, wherein the
impregnated composition material is phenol resin or resin in which
an inorganic material such as silica is dispersed into phenol
resin, epoxy based resin or acrylic resin.
[0011] In accordance with yet a further aspect of the present
invention, there is provided a magnetostriction device, wherein the
impregnated composition material has a powder-like material with a
high magnetic permeability dispersed thereto.
[0012] According to the present invention, since the impregnated
composition material is impregnated into the holes of the
magnetostrictive sintered material, it is possible to improve the
mechanical strength of this magnetostriction device.
[0013] Also, the magnetostriction device according to the present
invention has the powder-like material with the high magnetic
permeability dispersed into the above-mentioned impregnated
composition material.
[0014] Further, according to the present invention, since the
impregnated composition material in which the powder-like material
with the high magnetic permeability is dispersed is impregnated and
caked into the holes of the magnetostrictive sintered material, the
mechanical strength of this magnetostriction device can be improved
and the magnetic permeability thereof also can be improved.
[0015] Furthermore, according to the present invention, the
mechanical strength of the magnetostriction device manufactured by
the powder metallurgy method can be improved and the magnetic
permeability thereof also can be improved.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] FIG. 1 is a perspective view showing a magnetostriction
device according to an embodiment of the present invention.
[0017] FIG. 2 is a diagram showing examples of characteristic
curves indicating measured results of magnetostrictive properties
of a magnetostriction device; and
[0018] FIG. 3 is a schematic cross-sectional view showing an
example of an actuator using a magnetostriction device.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0019] A magnetostriction device according to the embodiments of
the present invention will be described with reference to the
drawings.
[0020] In this embodiment, first, a magnetostrictive sintered
material having a predetermined shape is formed by a powder
metallurgy method similar to the related art. More specifically,
Fe.sub.2Tb, Fe.sub.2Dy are ground in the atmosphere of Ar gas to
produce powder of a particle size of approximately 10 .mu.mesh as a
binary alloy of a rare earth-3d element having a large magnetic
anisotropy.
[0021] Next, after the above powder was mixed well, the resulting
product is processed by a magnetic press treatment under the
magnetic field ranging of from 10 to 15 kOe and thereby a pressed
powder molded material having a predetermined shape is
manufactured. In this case, it is possible to manufacture a pressed
powder molded material having an arbitrary shape.
[0022] Further, this pressed powder molded material is temporarily
sintered in the atmosphere of Ar gas with pressure of 1.1 at the
temperature ranging of from 1200.degree. C. to 1250.degree. C. for
30 minutes. After that, the resultant product was sintered at the
temperature ranging of from 900.degree. C. to 1100.degree. C. for
200 hours and thereby a magnetostrictive sintered material 10
having a predetermined shape shown in FIG. 1 was manufactured.
[0023] The resultant magnetostrictive sintered material 10 is a
Tb.sub.0.3Dy.sub.0.7Fe.sub.2 alloy and magnetic properties of 1.2
ppm were obtained under the magnetic field less than 1 kOe as shown
by the curve a in FIG. 2.
[0024] According to the embodiment of the present invention, it is
possible to manufacture the magnetostrictive sintered material 10
with the arbitrary shape and the high magnetic properties at a
relatively low manufacturing cost. The magnetostrictive sintered
material 10 manufactured by this powder metallurgy method has
innumerable extremely small holes 10a as shown in FIG. 1.
[0025] In this embodiment, this magnetostrictive sintered material
10 was processed by the following treatment.
INVENTIVE EXAMPLE 1
[0026] The impregnated composition material was impregnated into
this magnetostrictive sintered material 10 and cured by using
impregnation phenol resin (manufactured by Sumitomo Bakelite
Company Limited under the trade name of "PR-9183B") as the
impregnated composition material as follows.
[0027] First, the magnetostrictive sintered material 10 is rinsed
in the pre-treatment process. After that, this magnetostrictive
sintered material 10 is set within a tank and this tank is
evacuated to let an air out of the holes 10a of the
magnetostrictive sintered material 10. After that, the impregnation
phenol resin that is the impregnated composition material is
injected into this tank and this magnetostrictive sintered material
10 is dipped into this impregnation phenol resin.
[0028] After that, this impregnation phenol resin is impregnated
into the holes 10a of the magnetostrictive sintered material 10 by
returning the tank to the atmospheric pressure.
[0029] Next, the magnetostrictive sintered material 10 is taken out
of the tank and extra impregnation phenol resin is removed from the
surface of the magnetostrictive sintered material 10 by rinsing.
Thereafter, the resultant product is dried at 150.degree. C. in the
air and impregnation phenol resin in the holes 10a is cured. Thus,
the impregnation and curing treatment is completed.
[0030] When flexural strength of the magnetostriction device in
which impregnation phenol resin was impregnated and cured into the
holes 10a of the magnetostrictive sintered material 10 was measured
by a three-point flexural measurement method, the flexural strength
of this magnetostriction device was about 28 MPa, and it could be
confirmed that the flexural strength of the magnetostriction device
according to the present invention is large as compared with
flexural strength of 23.4 MPa of a magnetostriction device made of
a magnetostrictive sintered material in which this impregnation
phenol resin is not impregnated and cured into the holes 10a.
INVENTIVE EXAMPLE 2
[0031] Impregnation phenol resin (manufactured by Sumitomo Bakelite
Company Limited under the trade name of "PR-9183B") is used as a
impregnated composition material, and powder (particle size thereof
lies in a range of from 5 to 20 microns) of iron (that is, iron
equivalent to S15C), which is a ferromagnetic material, is
dispersed into this impregnation phenol resin with a weight ratio
of "5" of impregnation phenol resin to "1" of iron powder. This
mixed impregnation phenol resin product is impregnated and cured
into the holes 10a of the magnetostrictive sintered material 10 as
follows.
[0032] First, the magnetostrictive sintered material 10 is rinsed
in the pre-treatment process. After that, this magnetostrictive
sintered material 10 is set within in a tank and this tank is
evacuated to let an air out of the holes 10a of the
magnetostrictive sintered material 10. After that, the impregnation
phenol resin in which the powder of the ferromagnetic material was
dispersed is injected into this tank and this magnetostrictive
sintered material 10 is dipped into the impregnation phenol resin
into which the powder of the ferromagnetic material was
dispersed.
[0033] After that, the impregnation phenol resin in which the
powder of the ferromagnetic material was dispersed is impregnated
into the holes 10a of this magnetostrictive sintered material 10 by
returning the tank into the atmospheric pressure.
[0034] Next, the magnetostrictive sintered material 10 is taken out
of the tank and extra impregnation phenol resin in which the powder
of the ferromagnetic material was dispersed is removed from the
surface of the magnetostrictive sintered material 10 by rinsing.
Thereafter, the resultant product is dried at 150.degree. C. in the
air and the impregnation phenol resin in which the powder of the
ferromagnetic material was dispersed in the holes 10a is cured.
Thus, the impregnation and curing treatment is completed.
[0035] When flexural strength of the magnetostriction device in
which impregnation phenol resin in which the powder of the
ferromagnetic material was dispersed was impregnated and cured into
the holes 10a of the magnetostrictive sintered material 10 was
measured by a three-point flexural measurement method, the flexural
strength of this magnetostriction device was about 30 MPa, and it
could be confirmed that the flexural strength of the
magnetostriction device according to the present invention is large
as compared with flexural strength of 23.4 MPa of the
magnetostriction device made of the magnetostrictive sintered
material in which this impregnation phenol resin is not impregnated
and cured.
[0036] Also, it could be confirmed that the magnetic permeability
of the magnetostriction device in which the impregnation phenol
resin in which the ferromagnetic material powder was dispersed is
impregnated and cured into the holes 10a of this magnetostrictive
sintered material 10 is increased approximately 5% as compared with
that of the magnetostriction device in which the impregnation
phenol resin in which this ferromagnetic material was dispersed is
not impregnated and cured into the holes 10a of this
magnetostrictive sintered material 10.
[0037] As described above, according to the embodiments of the
present invention, the mechanical strength of the magnetostriction
device manufactured by the powder metallurgy method can be improved
and the magnetic permeability of the magnetostriction device
manufactured by this powder metallurgy method also can be
improved.
[0038] While the impregnation phenol resin was used as the
impregnated composition material in the above-mentioned examples,
the present invention is not limited thereto and phenol resin,
resin in which an inorganic material such as silica is dispersed
into phenol resin, epoxy based resin or acrylic resin can be used
as the above-mentioned impregnated composition material.
[0039] While the iron was used as the ferromagnetic material in the
above-mentioned examples, the present invention is not limited
thereto and other suitable materials such as permalloy and
magnetite can be used as the above-mentioned ferromagnetic
material.
[0040] According to the present invention, there is provided a
magnetostriction device in which an impregnated composition
material is impregnated into and caked into holes of a
magnetostrictive sintered material manufactured by a powder
metallurgy method.
[0041] According to the present invention, there is provided a
magnetostriction device in which a magnetostrictive sintered
material of Tb.sub.0.3Dy.sub.0.7Fe.sub.2 is made of powder ground
from Fe.sub.2Tb, Fe.sub.2Dy by a powder metallurgy method, an
impregnated composition material being impregnated and caked into
the holes of the magnetostrictive sintered material.
[0042] Further, according to the present invention, there is
provided a magnetostriction device, wherein the impregnated
composition material is phenol resin or resin, resin in which an
inorganic material such as silica is dispersed into phenol resin,
epoxy based resin or acrylic resin.
[0043] Further, according to the present invention, there is
provided a magnetostriction device, wherein the impregnated
composition material has a powder-like material with a high
magnetic permeability dispersed thereto.
[0044] According to the present invention, since the impregnated
composition material is impregnated into the holes of the
magnetostrictive sintered material, it is possible to improve
mechanical strength of this magnetostriction device.
[0045] Also, the magnetostriction device according to the present
invention has the powder-like material with the high magnetic
permeability dispersed into the above-mentioned impregnated
composition material.
[0046] Further, according to the present invention, since the
impregnated composition material in which the powder-like material
with the high magnetic permeability is dispersed is impregnated and
caked into the holes of the magnetostrictive sintered material, the
mechanical strength of this magnetostriction device can be improved
and the magnetic permeability thereof also can be improved.
[0047] Furthermore, according to the present invention, the
mechanical strength of the magnetostriction device manufactured by
the powder metallurgy method can be improved and the magnetic
permeability thereof also can be improved.
[0048] Having described preferred embodiments of the invention with
reference to the accompanying drawings, it is to be understood that
the invention is not limited to those precise embodiments and that
various changes and modifications could be effected therein by one
skilled in the art without departing from the spirit or scope of
the invention as defined in the appended claims.
* * * * *