US4388828A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Liquid gaging system sensor calibration
Assignee: Honeywell Inc
•
Filing: 1980-05-14
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Granted: 1983-06-21
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Expires: 2000-05-14
Abstract
Abstract The present invention is part of a liquid gaging system and comprises an apparatus for measuring and storing a value related to an unwetted capacitance of a capacitive sensor, the stored value being available for use in liquid measurements. Included is a capacitive sensor for mounting in a tank, the sensor having an unwetted capacitance variable in dependence on manufacturing tolerances. The sensor capacitance is also related to stray capacitance in the system. The invention further includes apparatus for measuring the sensor unwetted capacitance including the sensor capacitance contributed by the stray capacitance in the system. The apparatus for measuring is connected to the sensor. The invention also comprises apparatus for storing a value related to the sensor unwetted capacitance measured by the apparatus for measuring, the apparatus for storing being connected to the apparatus for measuring.
Inventors
- 👤 William R. Dougherty
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 12:19
CPC Classifications
G; G01; G01F; G01F23/00; G01F23/22; G01F23/26; G01F23/263
Claims Analysis
Total Claims: 24
Claim 1
Independent Claim
126 words
In a liquid gaging system, an apparatus for measuring and storing a value related to an unwetted capacitance of a capacitive sensor, the stored value being available for use in liquid measurements, comprising: a capacitive sensor for mounting in a tank, the sensor having an unwetted capacitance variable in dependence on manufacturing tolerances, the sensor capacitance also being related to a stray capacitance in the system; processor means having digital-to-analog converter means for automatically determining the sensor unwetted capacitance including the sensor capacitance contributed by the stray capacitance in the system, the processor means being connected to the sensor; and means for storing a value related to the sensor unwetted capacitance determined by the processor means, the means for storing being connected to the processor means.
Claim 2
Dependent Claim
126 words
In a liquid gaging system, an apparatus for measuring and storing a value related to an unwetted capacitance of a capacitive sensor, the stored value being available for use in liquid measurements, comprising: a capacitive sensor for mounting in a tank, the sensor having an unwetted capacitance variable in dependence on manufacturing tolerances, the sensor capacitance also being related to a stray capacitance in the system; processor means having digital-to-analog converter means for automatically determining the sensor unwetted capacitance including the sensor capacitance contributed by the stray capacitance in the system, the processor means being connected to the sensor; and means for storing a value related to the sensor unwetted capacitance determined by the processor means, the means for storing being connected to the processor means.
Claim 3
Dependent Claim
22 words
The apparatus of claim 1 wherein the means for storing comprises means for storing a digital number related to the sensor capacitance.
Claim 4
Dependent Claim
14 words
The apparatus of claim 2 wherein the means for storing comprises a non-volatile memory.
Claim 5
Dependent Claim
22 words
The apparatus of claim 2 or 3 wherein the sensor comprises a capacitive probe having an essentially uniform capacitance per unit length.
Claim 6
Dependent Claim
20 words
The apparatus of claim 1 wherein the sensor comprises a capacitive probe having an essentially uniform capacitance per unit length.
Claim 7
Dependent Claim
22 words
The apparatus of claim 5 wherein the means for storing comprises means for storing a digital number related to the sensor capacitance.
Claim 8
Dependent Claim
14 words
The apparatus of claim 6 wherein the means for storing comprises a non-volatile memory.
Claim 9
Dependent Claim
15 words
The apparatus of claim 2 or 3 wherein the sensor comprises a capacitive dielectric sensor.
Claim 10
Dependent Claim
13 words
The apparatus of claim 1 wherein the sensor comprises a capacitive dielectric sensor.
Claim 11
Dependent Claim
22 words
The apparatus of claim 9 wherein the means for storing comprises means for storing a digital number related to the sensor capacitance.
Claim 12
Dependent Claim
14 words
The apparatus of claim 10 wherein the means for storing comprises a non-volatile memory.
Claim 13
Dependent Claim
136 words
In a liquid gaging system, an apparatus for measuring and storing a value related to an unwetted capacitance of a capacitive sensor, the stored value being available for use in liquid measurements, comprising: a plurality of capacitive sensors for mounting in a tank, each sensor having a capacitance variable in dependence on manufacturing tolerances, the capacitance of each sensor also being related to a stray capacitance in the system; means for selectively measuring the unwetted capacitance of an individual sensor including the capacitance of the individual sensor contributed by the stray capacitance in the system, the means for selectively measuring being connected to the sensors; and means for storing a value related to the sensor unwetted capacitance measured by the means for selectively measuring, the means for storing being connected to the means for selectively measuring.
Claim 14
Dependent Claim
136 words
In a liquid gaging system, an apparatus for measuring and storing a value related to an unwetted capacitance of a capacitive sensor, the stored value being available for use in liquid measurements, comprising: a plurality of capacitive sensors for mounting in a tank, each sensor having a capacitance variable in dependence on manufacturing tolerances, the capacitance of each sensor also being related to a stray capacitance in the system; means for selectively measuring the unwetted capacitance of an individual sensor including the capacitance of the individual sensor contributed by the stray capacitance in the system, the means for selectively measuring being connected to the sensors; and means for storing a value related to the sensor unwetted capacitance measured by the means for selectively measuring, the means for storing being connected to the means for selectively measuring.
Claim 15
Dependent Claim
22 words
The apparatus of claim 12 wherein the means for storing comprises means for storing a digital number related to the sensor capacitance.
Claim 16
Dependent Claim
14 words
The apparatus of claim 13 wherein the means for storing comprises a non-volatile memory.
Claim 17
Dependent Claim
26 words
The apparatus of claim 13 or 14 wherein at least one of the sensors comprises a capacitive probe having an essentially uniform capacitance per unit length.
Claim 18
Dependent Claim
24 words
The apparatus of claim 12 wherein at least one of the sensors comprises a capacitive probe having an essentially uniform capacitance per unit length.
Claim 19
Dependent Claim
22 words
The apparatus of claim 16 wherein the means for storing comprises means for storing a digital number related to the sensor capacitance.
Claim 20
Dependent Claim
14 words
The apparatus of claim 17 wherein the means for storing comprises a non-volatile memory.
Claim 21
Dependent Claim
19 words
The apparatus of claim 13 or 14 wherein at least one of the sensors comprises a capacitive dielectric sensor.
Claim 22
Dependent Claim
17 words
The apparatus of claim 12 wherein at least one of the sensors comprises a capacitive dielectric sensor.
Claim 23
Dependent Claim
22 words
The apparatus of claim 20 wherein the means for storing comprises means for storing a digital number related to the sensor capacitance.
Claim 24
Dependent Claim
14 words
The apparatus of claim 21 wherein the means for storing comprises a non-volatile memory.
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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) | 1986-06-20 | 1986-12-20 | 1987-06-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-06-20 | 1990-12-20 | 1991-06-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-06-20 | 1994-12-20 | 1995-06-21 | $7700.00 | Window Closed / Lapsed |