U.S. patent number 10,720,856 [Application Number 16/170,461] was granted by the patent office on 2020-07-21 for composite actuator device driven by an electrostatic attractive force when a voltage is applied.
This patent grant is currently assigned to Korea Institute of Science and Technology. The grantee listed for this patent is KOREA INSTITUTE OF SCIENCE AND TECHNOLOGY. Invention is credited to Youngsu Cha, Kahye Song.
United States Patent |
10,720,856 |
Cha , et al. |
July 21, 2020 |
Composite actuator device driven by an electrostatic attractive
force when a voltage is applied
Abstract
A composite actuator device includes a composite material that
is configured to be driven by applying power thereto and that is
composed of a silicone; and from 1 to 20 wt % of an iron oxide
mixed in the silicone; and a metal plate that is spaced apart from
the composite material by a predetermined distance. When the power
is applied, the composite actuator is driven toward the metal plate
by an electrostatic attractive force. Preferably, the composite
actuator device has a resonance frequency of 3.+-.0.1 Hz.
Inventors: |
Cha; Youngsu (Seoul,
KR), Song; Kahye (Seoul, KR) |
Applicant: |
Name |
City |
State |
Country |
Type |
KOREA INSTITUTE OF SCIENCE AND TECHNOLOGY |
Seoul |
N/A |
KR |
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Assignee: |
Korea Institute of Science and
Technology (Seoul, KR)
|
Family
ID: |
69640160 |
Appl.
No.: |
16/170,461 |
Filed: |
October 25, 2018 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20200076328 A1 |
Mar 5, 2020 |
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Foreign Application Priority Data
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Sep 4, 2018 [KR] |
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10-2018-0105390 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H02N
1/006 (20130101); C08K 3/22 (20130101); C08K
3/22 (20130101); C08L 83/04 (20130101); C08K
2003/2275 (20130101) |
Current International
Class: |
H02N
1/00 (20060101); C08K 3/22 (20060101); H01L
41/09 (20060101) |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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2 542 271 |
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Feb 2014 |
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EP |
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10-1095024 |
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Dec 2011 |
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KR |
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10-1790880 |
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Oct 2017 |
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KR |
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10-1812445 |
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Dec 2017 |
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KR |
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Other References
L Z. Chen et al., "Electrothermal actuation based on carbon
nanotube network in silicone elastomer", Applied Physics Letters,
2008, pp. 263104, vol. 92. cited by applicant .
Cevher Ak et al., "A New Analytical Model to Estimate the Voltage
Value and Position of the Pull-In Limit of a MEMS Cantilever",
Micromachines, 2016, pp. 1-12, vol. 7, No. 53. cited by
applicant.
|
Primary Examiner: Martin; Edgardo San
Attorney, Agent or Firm: Rabin & Berdo, P.C.
Claims
What is claimed is:
1. A composite actuator device, comprising: a composite actuator
that comprises a silicone; and from 1 to 20 wt % of iron oxide
particles that are mixed in the silicone and that have a lump
shape; and a single electrode that is connected to one end of the
composite actuator and that has an electrical polarity configured
to charge polarize the iron oxide particles when a voltage is
applied between the electrode and an external object that is spaced
apart from the composite actuator and that has an opposite
electrical polarity such that the composite actuator is driven to
move toward the external object by an electrostatic force between
the iron oxide particles and the external object.
2. The composite actuator device according to claim 1, wherein the
iron oxide is Fe.sub.3O.sub.4.
3. A composite actuator device, comprising: a composite actuator
including a silicone; and from 1 to 20 wt % of iron oxide mixed in
the silicone, the composite actuator being configured to be driven
by applying a power thereto, and a metal plate installed to be
spaced apart from the composite actuator by a predetermined
distance, wherein the iron oxide is Fe.sub.3O.sub.4, and wherein,
when power is applied, the composite actuator is driven toward the
metal plate by an electrostatic attractive force.
4. The composite actuator device according to claim 2, wherein the
iron oxide is present in an amount of from 4.9 to 5.1 wt %.
5. The composite actuator device according to claim 2, wherein the
composite actuator device has a resonance frequency of 3.+-.0.1
Hz.
6. The composite actuator device according to claim 1, wherein the
external object is a metal plate.
7. The actuator device according to claim 3, wherein the composite
actuator includes the iron oxide in an amount of 4.9 to 5.1 wt
%.
8. The actuator device according to claim 3, wherein the composite
actuator has a resonance frequency of 3.+-.0.1 Hz.
Description
CROSS-REFERENCE TO RELATED APPLICATION
This application claims priority to Korean Patent Application No.
10-2018-0105390, filed on Sep. 4, 2018, and all the benefits
accruing therefrom under 35 U.S.C. .sctn. 119, the contents of
which in its entirety are herein incorporated by reference.
BACKGROUND
1. Field
The present disclosure relates to a composite actuator device, and
more particularly, to a composite actuator device driven by an
electrostatic force using charge polarization of an iron oxide and
a silicone composite.
2. Description of the Related Art
As an example of a flexible actuator, an electroactive polymer
(EAP) actuator is known in the art.
The EAP refers to an `electroactive polymer` that shrinks when
electricity is transmitted, and the EAP is used for artificial
limbs for disabled persons who require muscle movement, airship
wings, artificial heart valves, and artificial skins of fish
robots.
The electroactive polymer (EAP) actuator is driven by electrical
stimulation and chemical stimulation such as optics and heat.
In addition, the EAP actuator includes a dielectric and an elastic
actuator, and the electric field-induced activation reaction is
triggered by an electrostatic attraction force between two charged
conductive layers.
An ion EAP actuator operates by the movement of ions within a
polymer. The ion EAP actuator varies discretely due to small
changes in external variables, temperature, solvent quality and pH.
Examples of the ion EAP include polymer electrolyte gel, conductive
polymer and bucky gel actuators.
Recently, research on new materials and its manufacturing has been
continued, and it is required to develop actuators capable of
improving thermal stability and mechanical performance of
materials.
SUMMARY
The present disclosure is directed to providing an actuator device,
which may improve thermal stability and mechanical performance of
materials.
In one aspect, there is provided a composite actuator device,
comprising a composite actuator including a silicone and an iron
oxide disposed to be mixed inside the silicone, the composite
actuator being configured to be driven by applying a power thereto,
wherein the composite actuator includes the iron oxide in an amount
of 1 to 20 wt %.
In an embodiment of the present disclosure, the iron oxide may be
Fe.sub.3O.sub.4.
In another embodiment of the present disclosure, the composite
actuator device of the present disclosure may further comprise a
metal plate installed to be spaced apart from the composite
actuator by a predetermined distance, wherein when a power is
applied, the composite actuator may be driven toward the metal
plate by an electrostatic attractive force.
Preferably, the composite actuator may include the iron oxide in an
amount of 4.9 to 5.1 wt %.
The composite actuator may have a resonance frequency of 3.+-.0.1
Hz.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a diagram showing an example of a composite actuator
device, where an electrostatic force is generated at the composite
actuator of the present disclosure by charge polarization.
FIG. 2 is a diagram showing an example of the composite actuator
device according to the present disclosure.
FIG. 3A is a diagram showing a state of the composite actuator
before operation.
FIG. 3B is a diagram showing an example where the composite
actuator is driven toward a metal plate.
FIG. 3C is a diagram showing another example where the composite
actuator is driven toward the metal plate.
FIG. 4 is a table showing a displacement at each concentration of
iron oxide of the composite actuator at a resonance frequency.
DETAILED DESCRIPTION
Hereinafter, the embodiments disclosed in this specification will
be described in detail. Here, identical or similar components are
denoted by identical or similar reference symbols and not described
in detail again. In the following description, the word "unit" used
in terms is selected or endowed only in consideration of ease
naming and does not have any distinguishable meaning or role. In
addition, in the following description of the embodiments of the
present disclosure, any detailed description of related arts can be
omitted if it is determined that the gist of the embodiments
disclosed herein can be obscured by the same. Moreover, it should
be understood that the accompanying drawings are just for better
understanding of the embodiments disclosed herein and are not to be
construed as limiting the scope of the present disclosure. The
scope of the present disclosure should be understood as including
all changes, equivalents and alternatives thereof.
Terms having an ordinal such as "first" and "second" can be used
for explaining various components, but the components are not
limited by the terms. These terms are just used for distinguishing
any component from another.
In case it is mentioned that any component is "connected" to
another component, the component may be connected directly to
another component, but it should be understood that any other
component can be further interposed between them.
The singular expressions are intended to include the plural forms
as well, unless the context clearly indicates otherwise.
In this specification, the term such as "include" and "have" is
just to specify the presence of features, integers, steps,
operations, elements, parts or components thereof, stated in the
specification, but does not preclude the presence or addition of
one or more other features, integers, steps, operations, elements,
parts or components thereof.
First, a composite actuator device 100 according to the present
disclosure includes a composite actuator 10.
The composite actuator 10 includes a silicone 13 and an iron oxide
17, and the composite actuator 10 is configured to be driven by
applying a power thereto.
When a power is applied, charges are polarized at the iron oxide
17, and the silicone 13 is driven by an electrostatic force between
an electrode of an external panel and the iron oxide.
The iron oxide 17 is disposed to be mixed inside the silicone 13.
When a power is applied to polarize charges, the iron oxide 17
generates an electrostatic attractive force to the external
panel.
For example, the iron oxide 17 may be formed by solidifying
together with the silicone 13 so that it is distributed inside the
silicone 13 here and there in a lump shape.
FIG. 1 shows an example where the iron oxide 17 is disposed in the
silicone 13 to be distributed inside the silicone 13 here and there
in a lump shape, and an electrostatic force is generated by charge
polarization of the iron oxide 17.
In the composite actuator 10, the amount of the iron oxide 17 is 1
to 20 wt %. For example, the amount of the iron oxide 17 may be 4.9
to 5.1 wt %. In addition, in the composite actuator device 100 of
the present disclosure, the iron oxide 17 may be an iron oxide 17
with a chemical formula Fe.sub.3O.sub.4.
A power source may be electrically connected to the composite
actuator 10 to apply a power thereto.
The composite actuator device 100 of the present disclosure may
further include a metal plate 20. When a power is applied, the
composite actuator 10 may be driven toward the metal plate 20 by
the electrostatic attractive force.
The metal plate 20 may be disposed in parallel to the composite
actuator 10. So, when a power is applied, the composite actuator 10
is driven to move close to the metal plate 20.
The metal plate 20 may be made of, for example, aluminum (Al).
Powers with different polarities are preferably applied to the
metal plate 20 and the composite actuator 10.
FIG. 2 shows an example where electrodes 10a, 20a of different
polarities are connected to the composite actuator 10 and the metal
plate 20.
In addition, the composite actuator 10 preferably has a resonance
frequency of 3.+-.0.1 Hz in order to allow maximum actuation of the
composite actuator 10.
Due to this configuration, the composite actuator device 100 of the
present disclosure is driven by means of an electrostatic force
using charge polarization.
FIG. 3A shows a state before the composite actuator 10 operates,
FIG. 3B shows an example where the composite actuator 10 is driven
toward the metal plate 20, and FIG. 3C shows an example where the
composite actuator 10 is driven to vibrate toward the metal plate
20.
FIG. 4 shows a displacement at each concentration of the iron oxide
17 of the composite actuator 10, at the composite actuator device
100 according to the present disclosure. Here, the iron oxide 17
has a displacement of 3.1 mm at a concentration of 1 wt %, a
displacement of 3.92 mm at a concentration of 1.5 wt %, a
displacement of 4.29 mm at a concentration of 2 wt %, a
displacement of 4.98 mm at a concentration of 2.5 wt %, a
displacement of 5.19 mm at a concentration of 5 wt %, a
displacement of 4.94 mm at a concentration of 10 wt %, and a
displacement of 4.78 mm at a concentration of 20 wt %.
From the results in FIG. 4, it can be found that a maximum
displacement is generated when the iron oxide 17 has a
concentration of about 5 wt %.
Meanwhile, the composite actuator device 100 of the present
disclosure may be utilized for patient rehabilitation, soft robot
parts, continuum robots, small drilling devices, and vibration
generation or tactile feedback devices.
The composite actuator device of the present disclosure may be
driven by an electrostatic force between an electrode of an
external panel and the composite as charges are polarized at an
iron oxide in the composite actuator when a voltage is applied
thereto.
The composite actuator device of the present disclosure may be
utilized for patient rehabilitation, soft robot parts, continuum
robots, small drilling devices, and vibration generation or tactile
feedback devices.
The composite actuator device 100 described above is not limited to
the configuration and method of the embodiments described above,
and the embodiments may be modified in various ways by selectively
combining all or a part of the embodiments.
It will be apparent to those skilled in the art that the present
disclosure can be embodied in other specific forms without
departing from the essential characteristics of the present
disclosure. Accordingly, the above detailed description should be
considered in all respects as illustrative and not restrictive. The
scope of the present disclosure shall be determined by rational
interpretation of the appended claims, and all changes within the
equivalence scope of the present disclosure shall fall within the
scope of the present disclosure.
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