US3663842A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Elastomeric graded acoustic impedance coupling device
Assignee: Boeing North American Inc
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Filing: 1970-09-14
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Granted: 1972-05-16
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Expires: 1990-09-14
Abstract
Abstract An ultrasonic probe has a solid, flexible, elastic, graded acoustical impedance coupling device having fine geometrical and naturally shaped, metal and glass component powders, with their characteristic acoustic impedance values, disposed in graded varying concentrations in solid, elastomeric silicones, polyurethane, or the like low acoustic impedance, solid elastomers, providing a shaped, composite matrix coupling or a delay line. The graded matrix of component fine shaped powder in an elastomer provides a proximate matching impedance adjacent to the interface with the flat piezoelectric transducer at one device end, and a similar matching impedance near the interface to the inspected workpiece at the other device end, with intermediate low-loss graded impedance values inbetween. When a lens is employed, an effective tapered impedance can be obtained at the interface with the test article by graduating the solid concentrations primarily at the workpiece end. The elasticity of the device provides close conformation with the inspected workpiece surface, and reduces the acoustic reflection due to surface roughness and irregularities.
Inventors
- 👤 Darrow L Miller
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 02:39
CPC Classifications
B; B06; B06B; B06B1/00; B06B1/02; B06B1/06; B06B1/0644; B06B1/0662; B06B1/067; G; G01; G01N; G01N29/00; G01N29/22; G01N29/28; G10; G10K; G10K11/00; G10K11/002; G10K11/02
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
111 words
A coupling system for an ultrasonic probe having a piezoelectric element thereon, said system comprising: an elastomeric mass operatively affixed to said piezoelectric element to transmit ultrasonic signals from said element to a workpiece through said mass: a powdered particulate of hard material having an acoustic impedance value from about 1.7 X 106 to about 10.0 X 106 gram/cm.2-sec. dispersed in said elastomeric mass nonuniformly, the amount of said particulate being sufficient both to increase the acoustic velocity of said signals through said mass and to increase the density of said mass, the greatest concentration of said particulate being proximate a first surface of said mass farthest from said piezoelectric element.
Claim 2
Dependent Claim
111 words
A coupling system for an ultrasonic probe having a piezoelectric element thereon, said system comprising: an elastomeric mass operatively affixed to said piezoelectric element to transmit ultrasonic signals from said element to a workpiece through said mass: a powdered particulate of hard material having an acoustic impedance value from about 1.7 X 106 to about 10.0 X 106 gram/cm.2-sec. dispersed in said elastomeric mass nonuniformly, the amount of said particulate being sufficient both to increase the acoustic velocity of said signals through said mass and to increase the density of said mass, the greatest concentration of said particulate being proximate a first surface of said mass farthest from said piezoelectric element.
Claim 3
Dependent Claim
57 words
The structure set forth in claim 1 above, wHerein: said first surface of said elastomeric mass is adapted to contact a workpiece surface, and said concentration of said particulate is in an amount sufficient to provide an acoustic impedance in said elastomeric mass at said first surface thereof substantially equal to the acoustic impedance of said workpiece.
Claim 4
Dependent Claim
68 words
The structure set forth in claim 2 above, wherein: said piezoelectric element contacts a second surface of said elastomeric mass, and said powdered particulate is further concentrated in a portion of said elastomeric mass closest to said second surface thereof, and in an amount sufficient to produce an acoustic impedance in said elastomeric mass at said second surface substantially equal to the acoustic impedance of said piezoelectric element.
Claim 5
Dependent Claim
75 words
In an ultrasonic probe: a piezoelectric transducer for originating ultrasonic signals, a lens in contact with said transducer for focusing said signals, an elastomeric mass adapted at one end thereof to contact a workpiece surface and secured at its opposite end thereof to said lens for transmitting said focused signals to said workpiece surface, and a quantity of powdered material integrally contained and disposed within a portion of said elastomeric mass proximate said workpiece surface.
Claim 6
Dependent Claim
75 words
In an ultrasonic probe: a piezoelectric transducer for originating ultrasonic signals, a lens in contact with said transducer for focusing said signals, an elastomeric mass adapted at one end thereof to contact a workpiece surface and secured at its opposite end thereof to said lens for transmitting said focused signals to said workpiece surface, and a quantity of powdered material integrally contained and disposed within a portion of said elastomeric mass proximate said workpiece surface.
Claim 7
Dependent Claim
58 words
The structure set forth in claim 4 above, wherein: said quantity of powdered material is dispersed non-uniformly from a maximum concentration at a surface of said elastomeric mass adapted to contact said workpiece surface and tapering to a minimum concentration sufficient to produce a substantial change of the index of refraction between said elastomeric mass and said lens.
Claim 8
Dependent Claim
35 words
The structure set forth in claim 4 above, wherein: said workpiece surface is non-planar, and said portion of said elastomeric mass is shaped to provide a contoured surface oppositely corresponding to said non-planar workpiece surface.
Claim 9
Dependent Claim
68 words
An acoustic coupling device or delay line comprising: a shaped, solid, flexible, elastic, composite matrix, said matrix having fine geometrical or naturally shaped metal and siliceous powders of graded, controlled, acoustic impedance values disposed in a solid, elastomeric composition, said matrix having the mixture ratio value of metal and glass powder to elastomer concentration adapted to provide a uniform acoustic impedance match to proximate an adjacently disposed workpiece.
Claim 10
Dependent Claim
68 words
An acoustic coupling device or delay line comprising: a shaped, solid, flexible, elastic, composite matrix, said matrix having fine geometrical or naturally shaped metal and siliceous powders of graded, controlled, acoustic impedance values disposed in a solid, elastomeric composition, said matrix having the mixture ratio value of metal and glass powder to elastomer concentration adapted to provide a uniform acoustic impedance match to proximate an adjacently disposed workpiece.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-05-16 | 1975-11-15 | 1976-05-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-05-16 | 1979-11-15 | 1980-05-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-05-16 | 1983-11-15 | 1984-05-16 | $7700.00 | Window Closed / Lapsed |