US6511851B1
Expired / Lapsed
US
⏱️ 0.0 years remaining
Identifying changes in composition of liquids
Assignee: KAIKU 2007 Ltd
•
Filing: 1998-04-16
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Granted: 2003-01-28
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Expires: 2018-04-16
Abstract
Abstract A method for identifying a change in the composition of a liquid, comprising the steps of applying a time varying electrical or electromagnetic input signal to the liquid in a range of frequencies encompassing a resonant frequency of an electrical circuit comprising the liquid; measuring an impedance quantity of the electrical circuit comprising the liquid by means of the output signal as a function of the frequency of the time varying electrical or resonant frequency input signal in said range of frequencies; determining a resonant frequency of the electrical circuit comprising the liquid; after a change in the composition of the liquid, measuring variation in the impedance quantity at or near to the previously determined resonant frequency of the electrical circuit comprising the liquid; and relating the variation in the impedance quantity at or near to the resonant frequency of the electrical circuit comprising the liquid to a change in the composition of the liquid.
Inventors
- 👤 Peter Alfred Payne
- 👤 Richard Mark Dowdeswell
- 👤 Mohammed El Hassan Amrani
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 03:31
CPC Classifications
G; G01; G01N; G01N27/00; G01N27/02; G01N27/023; G01N33/00; G01N33/02; G01N33/14; G01N33/18; G01N33/1826; G01N33/26; G01N33/28
Claims Analysis
Total Claims: 42
Claim 1
Independent Claim
155 words
A method for identifying a change in the composition of a liquid, comprising the steps of: applying a time varying electrical or electromagnetic input signal to the liquid in a range of frequencies encompassing a resonant frequency of an electrical circuit comprising the liquid; measuring an impedance quantity of the electrical circuit comprising the liquid by means of the output signal as a function of the frequency of the time varying electrical or electromagnetic input signal in said range of frequencies; determining a resonant frequency of the electrical circuit comprising the liquid; after a change in the composition of the liquid, measuring a variation in the impedance quantity at or near to the previously determined resonant frequency of the electrical circuit comprising the liquid; and relating the variation in the impedance quantity at or near to the resonant frequency of the electrical circuit comprising the liquid to a change in the composition of the liquid.
Claim 2
Independent Claim
155 words
A method for identifying a change in the composition of a liquid, comprising the steps of: applying a time varying electrical or electromagnetic input signal to the liquid in a range of frequencies encompassing a resonant frequency of an electrical circuit comprising the liquid; measuring an impedance quantity of the electrical circuit comprising the liquid by means of the output signal as a function of the frequency of the time varying electrical or electromagnetic input signal in said range of frequencies; determining a resonant frequency of the electrical circuit comprising the liquid; after a change in the composition of the liquid, measuring a variation in the impedance quantity at or near to the previously determined resonant frequency of the electrical circuit comprising the liquid; and relating the variation in the impedance quantity at or near to the resonant frequency of the electrical circuit comprising the liquid to a change in the composition of the liquid.
Claim 3
Dependent Claim
29 words
A method according to claim 1 in which the time varying electrical input signal is an ac input signal and the frequency of the ac input signal is varied.
Claim 4
Dependent Claim
36 words
A method according to claim 1 in which the step of measuring the impedance quantity comprises a time to frequency domain transformation on the output signal or on the combination of the input and output signal.
Claim 5
Dependent Claim
15 words
A method according to claim 1 in which the time varying input signal is periodic.
Claim 6
Dependent Claim
30 words
A method according to claim 1 wherein the electrical input signal is applied via one or more electrodes or windings which are not in direct electrical contact with the liquid.
Claim 7
Dependent Claim
26 words
A method according to claim 5 in which the one or more electrodes or windings are encased within a non-conductive material, and disposed in the liquid.
Claim 8
Dependent Claim
17 words
A method according to claim 1 in which an inductor is used to adjust the resonant frequency.
Claim 9
Dependent Claim
16 words
A method according to claim 1 in which the input signal is a microwave electromagnetic signal.
Claim 10
Dependent Claim
22 words
A method according to claim 1 further comprising the step of analysing the measurement of the impedance quantity with artificial intelligence means.
Claim 11
Dependent Claim
17 words
A method according to claim 9 in which the artificial intelligence means comprises an artificial neural network.
Claim 12
Dependent Claim
28 words
A method according to claim 1 comprising the step of analysing the measurement of the impedance quantity with reference to a look up table or algorithm based system.
Claim 13
Dependent Claim
27 words
A method according to claim 9 in which the step of analysing the measurement of the impedance quantity accounts for the effect of temperature on the measurement.
Claim 14
Dependent Claim
15 words
A method according to claim 1 in which the temperature of the liquid is controlled.
Claim 15
Dependent Claim
29 words
A method according to claim 1 in which the change in the composition of the liquid is caused by the presence of one or more impurities in the liquid.
Claim 16
Dependent Claim
12 words
A method according to claim 1 in which the liquid is water.
Claim 17
Dependent Claim
28 words
A method according to claim 1 in which measurements are made at a plurality of locations, and data relating to the measurements are relayed to a central location.
Claim 18
Dependent Claim
12 words
A method according to claim 1 in which the liquid is non-conducting.
Claim 19
Dependent Claim
12 words
A method according to claim 17 in which the liquid is oil.
Claim 20
Dependent Claim
15 words
A method according to claim 18 in which the quality of the oil is monitored.
Claim 21
Dependent Claim
26 words
A method according to claim 1 in which the change in composition of the liquid is caused by the presence of a microorganism in the liquid.
Claim 22
Dependent Claim
16 words
A method according to claim 1 in which the liquid is a beverage or a foodstuff.
Claim 23
Dependent Claim
60 words
Apparatus for assessing the composition of a liquid comprising: electrical signal applying means adapted to apply a time varying electrical signal to the liquid; and measuring means for measuring an impedance quantity at, or near to, the resonant frequency of an electrical circuit comprising the liquid so that the resonant frequency, or varitions in the resonant frequency, can be detected.
Claim 24
Dependent Claim
60 words
Apparatus for assessing the composition of a liquid comprising: electrical signal applying means adapted to apply a time varying electrical signal to the liquid; and measuring means for measuring an impedance quantity at, or near to, the resonant frequency of an electrical circuit comprising the liquid so that the resonant frequency, or varitions in the resonant frequency, can be detected.
Claim 25
Dependent Claim
19 words
Apparatus according to claim 22 in which the electrical signal applying means applies an ac signal of variable frequency.
Claim 26
Dependent Claim
14 words
Apparatus according to claim 23 in which the measuring means comprises an impedance analyser.
Claim 27
Dependent Claim
23 words
Apparatus according to claim 22 in which the measuring means performs a time to frequency domain transformation of the time varying electrical signal.
Claim 28
Dependent Claim
14 words
Apparatus according to claim 25 in which the time varying electrical signal is periodic.
Claim 29
Dependent Claim
20 words
Apparatus according to claim 22 in which the electrical signal applying means is in direct electrical contact with the liquid.
Claim 30
Dependent Claim
24 words
Apparatus according to claim 27 in which the electrical signal applying means comprises at least two electrodes in direct electrical contact with the liquid.
Claim 31
Dependent Claim
25 words
Apparatus according to any of claims 22 to 26 in which the electrical signal applying means is not in direct electrical contact with the liquid.
Claim 32
Dependent Claim
28 words
Apparatus according to claim 29 in which a portion of the electrical signal applying means is encased within a non-conductive material, said portion being disposed in the liquid.
Claim 33
Dependent Claim
17 words
Apparatus according to claim 29 in which the electrical signal applying means are positioned around the liquid.
Claim 34
Dependent Claim
17 words
Apparatus according to claim 29 in which the electrical signal applying means comprises one or more electrodes.
Claim 35
Dependent Claim
17 words
Apparatus according to claim 29 in which the electrical signal applying means comprises at least two windings.
Claim 36
Dependent Claim
20 words
Apparatus according to claim 22 further comprising temperature control means adapted to maintain the liquid at a substantially constant temperature.
Claim 37
Dependent Claim
18 words
Apparatus according to claim 22 further comprising artificial intelligence means for analysing the measurement of an impedance quantity.
Claim 38
Dependent Claim
16 words
Apparatus according to claim 35 in which the artificial intelligence means is an artificial neural network.
Claim 39
Dependent Claim
20 words
A method as claimed in claim 1 wherein the time varying electrical input signal is a time varying electrical current.
Claim 40
Dependent Claim
18 words
The method according to claim 1 wherein the electrical circuit comprising the liquid is an open electrical circuit.
Claim 41
Dependent Claim
26 words
The method according to claim 1 wherein the electrical circuit comprising the liquid further comprises a container in which the liquid is contained and two electrodes.
Claim 42
Dependent Claim
22 words
The method according to claim 1 further comprising generating a time varying electrical or electromagnetic input signal in a closed oscillatory circuit.
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 2006-01-27 | 2006-07-29 | 2007-01-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2010-01-27 | 2010-07-29 | 2011-01-28 | $3760.00 | Window Closed / Lapsed |
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