US3820402A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrical pressure transducer
Assignee: General Electric Co
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Filing: 1973-03-20
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Granted: 1974-06-28
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Expires: 1993-03-20
Abstract
Abstract An electrical pressure transducer is described which responds to total pressure changes by variations in relative humidity changing the electrical impedance of a humidity sensing element. The pressure transducer has a sensing element which is sensitive to relative humidity, an enclosure surrounding the sensing element, a pair of electrical leads extending outwardly from the enclosure, a gas with a relative humidity within the enclosure, and pressure means associated with the enclosure to change the volume of the confined gas thereby varying the relative humidity of the gas.
Inventors
- 👤 L Interrante
- 👤 S Mitoff
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 10:13
CPC Classifications
F; F16; F16C; F16C11/00; F16C11/04; F16C11/06; F16C11/0619; F16C11/0623; F16C11/0628; F16C11/0633; F16C11/0638; B; B62; B62D; B62D7/00; B62D7/16; G; G01; G01L; G01L9/00; G01L9/0033; G01L9/0035; F16C2326/00; F16C2326/20; F16C2326/24
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
95 words
An electrical pressure transducer which comprises a humidity sensing element responsive to variations in atmospheric water content by electrical impedance changes, a gas-tight enclosure surrounding the sensing element, a pair of electrical leads connected to the sensing element and extending outwardly from the enclosure, a gas with a relative humidity confined within the gas-tight enclosure and in contact with the sensing element, and pressure means associated with the enclosure adapted to change the volume of the confined gas thereby varying the relative humidity of the gas and changing the electrical resistance of the sensing element.
Claim 2
Dependent Claim
95 words
An electrical pressure transducer which comprises a humidity sensing element responsive to variations in atmospheric water content by electrical impedance changes, a gas-tight enclosure surrounding the sensing element, a pair of electrical leads connected to the sensing element and extending outwardly from the enclosure, a gas with a relative humidity confined within the gas-tight enclosure and in contact with the sensing element, and pressure means associated with the enclosure adapted to change the volume of the confined gas thereby varying the relative humidity of the gas and changing the electrical resistance of the sensing element.
Claim 3
Dependent Claim
19 words
An electrical pressure transducer as in claim 1, in which the electrical impedance changes are changes in electrical resistance.
Claim 4
Dependent Claim
17 words
An electrical pressure transducer as in claim 1, in which the gas has a predetermined relative humidity.
Claim 5
Dependent Claim
142 words
An electrical pressure transducer which comprises a humidity sensing element responsive to variations in atmospheric water content by electrical impedance changes comprising an electrically insulating substrate, a pair of spaced apart interdigitated electrodes positioned on one surface of the substrate, an electrical lead in contact with each of the electrodes, and a thin film of chloromethylated quaternized polystyrene containing from 3.3 to 8.6 percent chlorine adhering to the electrode surface of the sensor, a gas-tight enclosure surrounding the sensing element, the electrical leads extending from the electrode outwardly through the enclosure, a gas with a relative humidity confined within the gas-tight enclosure and in contact with the sensing element, and pressure means associated with the enclosure adapted to change the volume of the confined gas thereby varying the relative humidity of the gas and changing the electrical resistance of the sensing element.
Claim 6
Dependent Claim
142 words
An electrical pressure transducer which comprises a humidity sensing element responsive to variations in atmospheric water content by electrical impedance changes comprising an electrically insulating substrate, a pair of spaced apart interdigitated electrodes positioned on one surface of the substrate, an electrical lead in contact with each of the electrodes, and a thin film of chloromethylated quaternized polystyrene containing from 3.3 to 8.6 percent chlorine adhering to the electrode surface of the sensor, a gas-tight enclosure surrounding the sensing element, the electrical leads extending from the electrode outwardly through the enclosure, a gas with a relative humidity confined within the gas-tight enclosure and in contact with the sensing element, and pressure means associated with the enclosure adapted to change the volume of the confined gas thereby varying the relative humidity of the gas and changing the electrical resistance of the sensing element.
Claim 7
Dependent Claim
22 words
An electrical pressure transducer as in claim 4, in which the electrically insulating substrate of the sensing element is a dense alumina.
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) | 1977-06-27 | 1977-12-27 | 1978-06-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-06-27 | 1981-12-27 | 1982-06-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-06-27 | 1985-12-27 | 1986-06-28 | $7700.00 | Window Closed / Lapsed |