US3676722A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Structure for bimorph or monomorph benders
Assignee: Motorola Solutions Inc
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Filing: 1971-04-15
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Granted: 1972-07-11
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Expires: 1991-04-15
Abstract
Abstract Bimorph benders comprised of a pair of piezoelectric wafers with a center vane of conductive material disposed therebetween or monomorph benders comprised of one piezoelectric wafer and one wafer of piezoelectrically inactive material with a center vane of conductive material disposed therebetween have one portion rigidly held in place and another portion coupled to move or be moved by a mechanical load thereby applying a distribution of bending forces to the bender. By selectively constructing the center vane so that the stiffness of the assembly varies in proportion to the magnitude of the bending force applied to the bender and by bending the wafers to conform to the shape of the center vane, increased coefficient of electromechanical coupling, strength, high frequency response, and linearity result.
Inventors
- 👤 Hugo W Schafft
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 13:56
CPC Classifications
H; H04; H04R; H04R17/00
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
298 words
A piezoelectric bender suitable for being attached and effectively operated between a movement restricting structure and a mechanical load, this operation creating bending forces of different magnitudes in predetermined incremental portions of the bender, such bender including in combination: a first circular member formed from piezoelectric material with at least first and second diametrically opposed edge portions being mechanically coupled to one of the movement restricting structure and the mechanical load, and a third portion intermediate said edge portions and which is mechanically coupled to the other of the movement restricting structure and the mechanical load, said first circular member being comprised of a plurality of integral incremental circular portions each having a different stiffness, said stiffnesses becoming proportionally greater toward said edge portions than the Magnitudes of the bending forces; first signal conducting means affixed to said first member for applying electrical signals thereto or deriving electrical signals therefrom; and a second circular member having first and second surfaces, said first surface being mechanically coupled to said first member, said second member further having first and second edge portions and a third portion of said second member being intermediate said edge portions thereof, said first, second and third portions of said second member being connected to said first, second and third portions, respectively, of said first member, said second member having integral, incremental portions constructed to have incremental stiffnesses which are greatest at said third portion of said second member and which decrease to where said incremental stiffnesses are least at said edge portions of said second member, said incremental portions of said first and second circular members cooperating to cause the composite stiffness of each of the predetermined incremental portions of the piezoelectric bender to be proportional to the magnitude of the bending forces applied thereto.
Claim 2
Dependent Claim
298 words
A piezoelectric bender suitable for being attached and effectively operated between a movement restricting structure and a mechanical load, this operation creating bending forces of different magnitudes in predetermined incremental portions of the bender, such bender including in combination: a first circular member formed from piezoelectric material with at least first and second diametrically opposed edge portions being mechanically coupled to one of the movement restricting structure and the mechanical load, and a third portion intermediate said edge portions and which is mechanically coupled to the other of the movement restricting structure and the mechanical load, said first circular member being comprised of a plurality of integral incremental circular portions each having a different stiffness, said stiffnesses becoming proportionally greater toward said edge portions than the Magnitudes of the bending forces; first signal conducting means affixed to said first member for applying electrical signals thereto or deriving electrical signals therefrom; and a second circular member having first and second surfaces, said first surface being mechanically coupled to said first member, said second member further having first and second edge portions and a third portion of said second member being intermediate said edge portions thereof, said first, second and third portions of said second member being connected to said first, second and third portions, respectively, of said first member, said second member having integral, incremental portions constructed to have incremental stiffnesses which are greatest at said third portion of said second member and which decrease to where said incremental stiffnesses are least at said edge portions of said second member, said incremental portions of said first and second circular members cooperating to cause the composite stiffness of each of the predetermined incremental portions of the piezoelectric bender to be proportional to the magnitude of the bending forces applied thereto.
Claim 3
Dependent Claim
50 words
The piezoelectric bender of claim 1 wherein said second member is comprised of homogeneous material having a thickness which is greatest at said third portion of said second member and which thickness continuously decreases to where it is least at said first and second edge portions of said second member.
Claim 4
Dependent Claim
15 words
The piezoelectric bender of claim 1 wherein said first circular member is substantially bowl shaped.
Claim 5
Dependent Claim
25 words
The piezoelectric bender of claim 1 wherein said third portion of said first circular member is located about the center of said first circular member.
Claim 6
Dependent Claim
106 words
The piezoelectric bender of claim 1 further including: a third circular member formed from piezoelectric material; second signal conducting means affixed to said third member for applying electrical signals thereto or deriving electrical signals therefrom; said second member being comprised of conductive material, said second surface of said second member being mechanically and electrically coupled to said third circular member to provide an electrical interconnection between said first and third members; and said first and said third members being polarized to move in opposite radial directions in response to an electrical potential being applied across said second member and said first and second signal conducting means.
Claim 7
Dependent Claim
15 words
The piezoelectric bender of claim 5 wherein said third circular member is substantially bowl shaped.
Claim 8
Dependent Claim
124 words
A piezoelectric bender, including in combination: at least a first bowl shaped element having an open end, said first element being comprised of piezoelectric material and having a pair of opposing faces; first electrode means affixed to at least one of said opposing faces; a resilient member having a center and first and second diametrically opposed edges and first and second sides with a plurality of raised portions having apices on at least said first side thereof, said apices having heights which are greatest at the center of said resilient member and which heights decrease from said center out toward the edge of said resilient member, said apices on the first side of said resilient member being affixed to said first bowl shaped element.
Claim 9
Dependent Claim
124 words
A piezoelectric bender, including in combination: at least a first bowl shaped element having an open end, said first element being comprised of piezoelectric material and having a pair of opposing faces; first electrode means affixed to at least one of said opposing faces; a resilient member having a center and first and second diametrically opposed edges and first and second sides with a plurality of raised portions having apices on at least said first side thereof, said apices having heights which are greatest at the center of said resilient member and which heights decrease from said center out toward the edge of said resilient member, said apices on the first side of said resilient member being affixed to said first bowl shaped element.
Claim 10
Dependent Claim
56 words
The piezoelectric bender of claim 7 wherein the open end of said first bowl shaped element is circular in shape, said resilient member is similar in shape to said shape of said open end and said raised portions on said resilient member are in the form of a three dimensional spiral having a gradually changing height.
Claim 11
Dependent Claim
36 words
The piezoelectric bender of claim 7 wherein said resilient member is circular in shape and said raised portions each lie within concentric circles of different radii which are centered about said center of said resilient member.
Claim 12
Dependent Claim
78 words
The piezoelectric bender of claim 7 further including: a second bowl shaped element having an oPen end; and said resilient member having a plurality of raised portions having apices on said second side thereof having heights which are greatest at the center of said resilient member and which decrease from said center out toward the edges of said resilient member, said apices on the second side of said resilient member being affixed to said second bowl shaped element.
Claim 13
Dependent Claim
38 words
The piezoelectric bender of claim 10 wherein said second bowl shaped element is comprised of piezoelectric material and said resilient member is made from electrically conductive material thus providing electrical contact between said first and second piezoelectric elements.
Claim 14
Dependent Claim
133 words
A bimorph bender including in combination: a pair of circular bowl shaped piezoelectric elements each having opposing inner faces with corresponding inner electrodes thereon; a circular center vane positioned between the inner faces of said pair of piezoelectric elements and acting to space the same apart in fixed relationship, said center vane having a central part and a peripheral part with corrugations located on said central part having apex portions on alternate sides thereon, said apex portions being in electrical contact with said inner electrodes; and said corrugations further being in the form of a spiral having an amplitude which is greatest at the center of the central part and which amplitude continually decreases along the length of the spiral to where said amplitude is least at the edge of said central part.
Claim 15
Dependent Claim
133 words
A bimorph bender including in combination: a pair of circular bowl shaped piezoelectric elements each having opposing inner faces with corresponding inner electrodes thereon; a circular center vane positioned between the inner faces of said pair of piezoelectric elements and acting to space the same apart in fixed relationship, said center vane having a central part and a peripheral part with corrugations located on said central part having apex portions on alternate sides thereon, said apex portions being in electrical contact with said inner electrodes; and said corrugations further being in the form of a spiral having an amplitude which is greatest at the center of the central part and which amplitude continually decreases along the length of the spiral to where said amplitude is least at the edge of said central part.
Claim 16
Dependent Claim
31 words
The bimorph bender of claim 12 wherein said center vane is comprised of conductive material which makes electrical contact between said inner faces of said pair of bowl shaped piezoelectric elements.
Claim 17
Dependent Claim
17 words
The bimorph bender of claim 12 wherein said peripheral part of said center vane includes radial corrugations.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-07-11 | 1976-01-10 | 1976-07-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-07-11 | 1980-01-10 | 1980-07-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-07-11 | 1984-01-10 | 1984-07-11 | $7700.00 | Window Closed / Lapsed |