Patent US4462262A successfully refreshed from Google Patents.
US4462262A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fluid flow sensing system
Assignee: Honeywell Inc
•
Filing: 1982-03-31
•
Granted: 1984-07-31
•
Expires: 2002-03-31
Abstract
Abstract A system for detecting changes in the electrical conductivity or capacitance of a fluid occasioned by the passage of a follower element is disclosed which includes a hollow fluid passage such as a flowmeter through which a fluid is caused to pass and is provided with at least one follower element of similar cross sectional shape to that of the passage and of a size slightly smaller than the passage which is free to move along the passage and has electrical conductance or capacitance properties substantially different from the fluid. At least one electrically-conductive sensor is disposed in the passage in electrical communication with the fluid. A detector circuit is utilized to sense changes in conductance or capacitance through said fluid in accordance with the presence of said follower element in the conductive path.
Inventors
- 👤 Joseph Kahnke
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 20:58
CPC Classifications
G; G01; G01F; G01F1/00; G01F1/05; G01F1/056; G01F1/704
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
202 words
A system for detecting changes in the electrical resistance or capacitance of a volumetric path through a field occasioned by the passage of a follower element comprising: a hollow fluid passage adapted to conduct a fluid; a follower element in said fluid of similar cross sectional shape to that of the passage and of the size slightly smaller than said passage such that the follower element is free to move along said passage, said follower element having electrical properties different from said fluid; a single electrode current sensor disposed in said passage in electrical communication with said fluid; a source of high frequency AC current connected to said sensor; detector circuit means connected to said sensor which detects changes in the AC electrical signal from said sensor in the presence of said follower element wherein said detector circuit further comprises a series resonant circuit including said source of high frequency AC current connected in series with an induction means and capacitive and resistive means associated with the flow of an electrical signal from said sensor through said fluid; means for detecting the change in the electrical signal produced by a change in either said capacitance or resistance characteristics of said detector circuit.
Claim 2
Independent Claim
202 words
A system for detecting changes in the electrical resistance or capacitance of a volumetric path through a field occasioned by the passage of a follower element comprising: a hollow fluid passage adapted to conduct a fluid; a follower element in said fluid of similar cross sectional shape to that of the passage and of the size slightly smaller than said passage such that the follower element is free to move along said passage, said follower element having electrical properties different from said fluid; a single electrode current sensor disposed in said passage in electrical communication with said fluid; a source of high frequency AC current connected to said sensor; detector circuit means connected to said sensor which detects changes in the AC electrical signal from said sensor in the presence of said follower element wherein said detector circuit further comprises a series resonant circuit including said source of high frequency AC current connected in series with an induction means and capacitive and resistive means associated with the flow of an electrical signal from said sensor through said fluid; means for detecting the change in the electrical signal produced by a change in either said capacitance or resistance characteristics of said detector circuit.
Claim 3
Dependent Claim
20 words
System according to claim 1 wherein said means for detecting the change in the electrical signal is a diode means.
Claim 4
Independent Claim
19 words
The system according to either of claims 1 or 2 wherein said induction means comprises a high "Q" inductor.
References Cited (Backward Citations)
US2349992A
Cited
US2288838A
Cited
US3444322A
Cited
US3385311A
Cited
GB1439598A
Cited
US3862100A
Cited
US4157660A
Cited
US4183060A
Cited
US4089220A
Cited
US4164866A
Cited
US4404860A
Cited
US4343191A
Cited
US4331036A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-07-31 | 1988-01-30 | 1988-07-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-07-31 | 1992-01-30 | 1992-07-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-07-31 | 1996-01-30 | 1996-07-31 | $7700.00 | Window Closed / Lapsed |