Patent US4949121A successfully refreshed from Google Patents.
Patent US5031453A successfully refreshed from Google Patents.
US5031453A
Expired / Lapsed
US
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System and method of error reduction for differential capacitive transducers
Assignee: Simmonds Precision Products Inc
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Filing: 1989-12-21
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Granted: 1991-07-16
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Expires: 2009-12-21
Abstract
No abstract record available.
Inventors
- 👤 Bruce R. Kline
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 20:22
CPC Classifications
G; G01; G01F; G01F23/00; G01F23/22; G01F23/26; G01F23/263; G01F23/268; G01F23/266
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
220 words
A method of determining the position of the upper surface of liquid fuel in a tank, comprising providing a ramp generator, amplifier means, liquid fuel in a tank, a first transducer means, a comparator, a switch means and a counter, said first transducer comprising a variable capacitor, said amplifier means having contacts, said amplifier means and said ramp generator being connected to said variable capacitor, said variable capacitor being positioned within said tank in contact with said liquid fuel, said liquid fuel having an upper surface, said amplifier means being connected to said switch means, said switch means being connected to said comparator and said counter, operating said ramp generator to provide voltage ramps, switching said switch means between said contacts in response to said voltage ramps to provide a first and a second signal set comprising first and second signals, each of said signals in said first set being substantially equal and opposite in magnitude to each of said signals in said second set, in each said set the time between said first and second signals being related to the position of said upper surface of said liquid fuel within said tank, determining said position of said upper surface of said liquid fuel from said times between said first and second signals of said first and said second sets.
Claim 2
Independent Claim
220 words
A method of determining the position of the upper surface of liquid fuel in a tank, comprising providing a ramp generator, amplifier means, liquid fuel in a tank, a first transducer means, a comparator, a switch means and a counter, said first transducer comprising a variable capacitor, said amplifier means having contacts, said amplifier means and said ramp generator being connected to said variable capacitor, said variable capacitor being positioned within said tank in contact with said liquid fuel, said liquid fuel having an upper surface, said amplifier means being connected to said switch means, said switch means being connected to said comparator and said counter, operating said ramp generator to provide voltage ramps, switching said switch means between said contacts in response to said voltage ramps to provide a first and a second signal set comprising first and second signals, each of said signals in said first set being substantially equal and opposite in magnitude to each of said signals in said second set, in each said set the time between said first and second signals being related to the position of said upper surface of said liquid fuel within said tank, determining said position of said upper surface of said liquid fuel from said times between said first and second signals of said first and said second sets.
Claim 3
Dependent Claim
12 words
The method of claim 1 wherein said transducer means comprises a capacitor.
Claim 4
Dependent Claim
13 words
The method of claim 2 wherein said capacitor comprises a readily rotatable plate.
Claim 5
Dependent Claim
37 words
The method of claim 3 wherein said transducer means further comprises a first, a second, and a third voltage amplifier, said first, second and third voltage amplifiers each being connected to said first and second transimpedance amplifiers.
Claim 6
Dependent Claim
17 words
The method of claim 1 wherein said transducer means comprises a first and a second transimpedance amplifier.
Claim 7
Dependent Claim
15 words
The method of claim 1 wherein said comparator means is connected to an optical source.
Claim 8
Dependent Claim
15 words
The method of claim 6 wherein said optical source is connected to an optical fiber.
Claim 9
Dependent Claim
15 words
The method of claim 7 wherein said optical fiber is connected to an optical detector.
Claim 10
Dependent Claim
13 words
The method of claim 8 wherein said detector is connected to a display.
Claim 11
Dependent Claim
48 words
The method of claim 1 further comprising providing a third signal in each of said first and second signal sets, the distribution in time of said second and said third signals in each said signal set being related to the position of said upper level of said fuel.
Claim 12
Dependent Claim
20 words
The method of claim 1 further comprising a second transducer means, said second transducer means being connected to said comparator.
Claim 13
Dependent Claim
11 words
The method of claim 11 wherein said transducers are capacitive transducers.
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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) | 1994-07-15 | 1995-01-14 | 1995-07-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-07-15 | 1999-01-14 | 1999-07-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-07-15 | 2003-01-14 | 2003-07-16 | $7700.00 | Window Closed / Lapsed |