Patent US2546951A successfully refreshed from Google Patents.
Patent US4442474A successfully refreshed from Google Patents.
US4442474A
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US
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Capacitive pressure transducer
Assignee: Vickers Inc
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Filing: 1981-12-14
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Granted: 1984-04-10
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Expires: 2001-12-14
Abstract
Abstract In a capacitive pressure transducer of the type having a flexible diaphragm, a "dimple" like or concave surface is formed therein in order to provide an air gap between the flexible diaphragm and a relatively rigid plate. When pressure is applied to the diaphragm, the diaphragm deflects providing a measurable change in capacitance which varies as a function of the applied pressure.
Inventors
- 👤 Joannes N. M. de Jong
- 👤 Richard L. Earle
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 09:59
CPC Classifications
H; H01; H01G; H01G5/00; H01G5/16; G; G01; G01L; G01L9/00; G01L9/0041; G01L9/0072
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
117 words
A capacitive pressure transducer comprising: a housing; a threaded cylindrical diaphragm disposed in said housing and including a flexible plate having a concave surface region therein; a relatively rigid plate having a groove conductive plate dielectrically separated from said flexible plate and disposed in said housing with insulation therebetween to be substantially parallel to regions of said flexible plate external to said concave surface region such that an airgap is formed between said relatively rigid plate and said concave surface region; adapter means threaded into said cylindrical diaphragm for directing fluid to said flexible plate; a cover for said housing; and spring-screw means mounted on said cover for exerting an adjustable force on said relatively rigid plate.
Claim 2
Dependent Claim
117 words
A capacitive pressure transducer comprising: a housing; a threaded cylindrical diaphragm disposed in said housing and including a flexible plate having a concave surface region therein; a relatively rigid plate having a groove conductive plate dielectrically separated from said flexible plate and disposed in said housing with insulation therebetween to be substantially parallel to regions of said flexible plate external to said concave surface region such that an airgap is formed between said relatively rigid plate and said concave surface region; adapter means threaded into said cylindrical diaphragm for directing fluid to said flexible plate; a cover for said housing; and spring-screw means mounted on said cover for exerting an adjustable force on said relatively rigid plate.
Claim 3
Dependent Claim
24 words
A capacitive pressure transducer according to claim 1 wherein said relatively rigid plate is fabricated from a conductive material coated with a dielectric material.
Claim 4
Dependent Claim
19 words
A capacitive pressure transducer according to claim 1 further includes a metallic plate disposed on said relatively rigid plate.
Claim 5
Dependent Claim
30 words
A capacitive pressure transducer according to claim 3 wherein said conductive material of said relatively rigid plate is aluminum and said dielectric material is an anodized coating of said aluminum.
Claim 6
Dependent Claim
15 words
A capactive pressure transducer according to claim 1 wherein said dielectric material consists of mica.
References Cited (Backward Citations)
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Cited
US3222581A
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US3308357A
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US4091683A
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US4332698A
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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) | 1987-04-10 | 1987-10-10 | 1988-04-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-04-10 | 1991-10-10 | 1992-04-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-04-10 | 1995-10-10 | 1996-04-10 | $7700.00 | Window Closed / Lapsed |