Patent US5869189A successfully refreshed from Google Patents.
US5869189A
Expired / Lapsed
US
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Composites for structural control
Assignee: Massachusetts Institute of Technology
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Filing: 1996-07-26
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Granted: 1999-02-09
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Expires: 2016-07-26
Abstract
Abstract Composites for actuating or sensing deformation. In embodiments, the composites have a series of flexible, elongated piezoelectric fibers arranged in a parallel array with adjacent fibers separated by relatively soft polymer. The piezoelectric fibers have a common poling direction transverse to their axial extension. The composite further includes flexible conductive material along the axial extension of the fibers for imposing or detecting an electric field.
Inventors
- 👤 Nesbitt W. Hagood, IV
- 👤 Aaron A. Bent
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 07:06
CPC Classifications
H; H10; H10N; H10N30/00; H10N30/702; B; B64; B64C; B64C27/00; B64C27/54; B64C27/72; H10N30/80; H10N30/85; H10N30/852; B64C2027/7205; B64C2027/7211; B64C2027/7222; H10N30/20; H10N30/204; H10N30/208; Y; Y02; Y02T; Y02T50/00; Y02T50/30; Y10; Y10T; Y10T428/00; Y10T428/31504; Y10T428/31678; Y10T428/31692
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
149 words
A composite for actuating or sensing deformation of a structural member, comprising: a series of flexible, elongated electro-ceramic fibers arranged in a parallel array, each fiber substantially in parallel with each other, with adjacent fibers separated by relatively soft deformable polymer having additives to vary the electric or elasticity properties of the polymer, each fiber having a common poling direction, and said composite having a length and width greater than a thickness of the composite and axial extension of said fibers being along the length of said composite, said composite further including flexible conductive electrode material along the axial extension of said fibers for imposing or detecting electric fields, said electrode material having an interdigitated pattern forming electrodes of opposite polarity that are spaced alternately and configured to apply a field having compounds along the axis of the fibers, said polymer being interposed between said electrode and said fibers.
Claim 2
Dependent Claim
149 words
A composite for actuating or sensing deformation of a structural member, comprising: a series of flexible, elongated electro-ceramic fibers arranged in a parallel array, each fiber substantially in parallel with each other, with adjacent fibers separated by relatively soft deformable polymer having additives to vary the electric or elasticity properties of the polymer, each fiber having a common poling direction, and said composite having a length and width greater than a thickness of the composite and axial extension of said fibers being along the length of said composite, said composite further including flexible conductive electrode material along the axial extension of said fibers for imposing or detecting electric fields, said electrode material having an interdigitated pattern forming electrodes of opposite polarity that are spaced alternately and configured to apply a field having compounds along the axis of the fibers, said polymer being interposed between said electrode and said fibers.
Claim 3
Dependent Claim
15 words
The composite of claim 1 wherein said additives increase the dielectric constant of the polymer.
Claim 4
Dependent Claim
16 words
The composite of claim 1 wherein the polymer has a Young's modulus of about 6 GPa.
Claim 5
Dependent Claim
28 words
The composite of claim 1 or 3 wherein the polymer has a Young's modulus that is at least five times less than the Young's modulus of the fibers.
Claim 6
Dependent Claim
14 words
The composite of claim 1 wherein said elongated electro-ceramic fibers comprise a piezoelectric material.
Claim 7
Dependent Claim
13 words
The composite of claim 1 wherein the fibers have a circular cross section.
Claim 8
Dependent Claim
13 words
The composite of claim 1 wherein the fibers have a rectangular cross section.
Claim 9
Dependent Claim
21 words
The composite of claim 1 wherein the additives are selected from the group consisting of graphite, metal, ceramic, and electro-ceramic materials.
Claim 10
Dependent Claim
13 words
The composite of claim 1 further comprising reinforcement fibers disposed within the polymer.
Claim 11
Dependent Claim
27 words
The composite of claim 9 wherein the reinforcement fibers are along the length of the composite and oriented transverse to the axial extension of the electro-ceramic fibers.
References Cited (Backward Citations)
US4330730A
Cited
US4407054A
Cited
US4400642A
Cited
US4565940A
Cited
US4626730A
Cited
US4613784A
Cited
US4933230A
Cited
US4849668A
Cited
US4868447A
Cited
US4868566A
Cited
US5083466A
Cited
US5095762A
Cited
US5101669A
Cited
US4958100A
Cited
WO1991012953A1
Cited
US5220296A
Cited
US5291090A
Cited
US5340510A
Cited
US5656882A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2002-02-08 | 2002-08-10 | 2003-02-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2006-02-08 | 2006-08-10 | 2007-02-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2010-02-08 | 2010-08-10 | 2011-02-09 | $7700.00 | Window Closed / Lapsed |