US3979958A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus for determining interface levels in ground cavities or containers containing liquid or gel-like material
Assignee: PPG Architectural Coatings Canada Inc
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Filing: 1976-01-13
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Granted: 1976-09-14
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Expires: 1996-01-13
Abstract
Abstract An apparatus is provided for determining the location of a liquid-liquid or a liquid-gas interface in tanks or cavities and has particular use in determining the position of the explosive collar level in boreholes charged with water gel explosives. The apparatus consists of a sensing element which may be lowered into a cavity. Air is exhausted from the sensing element into the surrounding medium. Any restriction to air flow caused by the surrounding medium causes an increase in air pressure which increase signals the presence of an interface.
Inventors
- 👤 Wladimir Janssen
- 👤 Harley Corey Prime
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 05:03
CPC Classifications
G; G01; G01F; G01F23/00; G01F23/14; G01F23/16; G01F23/161
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
144 words
An apparatus for determining an interface level in cavities or containers containing liquid material comprising: a. an elongated sensing element having a side wall annd being adapted for lowering into a liquid-containing cavity, said sensing element having two gas-conducting channels therethrough, said channels terminating in vertically spaced-apart exhaust ports in the said side wall; b. separate gas conduit means adapted to deliver pressurized gas at a constant flow rate into each of said channels and through said exhaust ports; c. pressure monitoring means associated with said gas conduits whereby any change or variation in gas pressure in or between said conduits caused by a restriction of gas flow from said exhaust ports may be sensed; and d. means associated with said pressure monitoring means whereby a signal may be generated when a change or variation in gas pressure in or between said conduits occurs.
Claim 2
Independent Claim
144 words
An apparatus for determining an interface level in cavities or containers containing liquid material comprising: a. an elongated sensing element having a side wall annd being adapted for lowering into a liquid-containing cavity, said sensing element having two gas-conducting channels therethrough, said channels terminating in vertically spaced-apart exhaust ports in the said side wall; b. separate gas conduit means adapted to deliver pressurized gas at a constant flow rate into each of said channels and through said exhaust ports; c. pressure monitoring means associated with said gas conduits whereby any change or variation in gas pressure in or between said conduits caused by a restriction of gas flow from said exhaust ports may be sensed; and d. means associated with said pressure monitoring means whereby a signal may be generated when a change or variation in gas pressure in or between said conduits occurs.
Claim 3
Dependent Claim
26 words
An apparatus as claimed in claim 1 also comprising gas pressure reducing means to provide gas at low pressure for passage into said conduits and channels.
Claim 4
Dependent Claim
13 words
An apparatus as claimed in claim 1 also comprising a gas pressure indicator.
Claim 5
Dependent Claim
25 words
An apparatus as claimed in claim 1 wherein the said sensing element is adapted for lowering into a liquid-containing cavity by a mechanical lowering device.
Claim 6
Dependent Claim
18 words
An apparatus as claimed in claim 1 wherein the said separate gas conduit means comprise flexible rubber hoses.
Claim 7
Dependent Claim
23 words
An apparatus as claimed in claim 1 wherein said sensing element is made of metal having a density greater than that of water.
Claim 8
Dependent Claim
24 words
An apparatus as claimed in claim 1 wherein the said pressure monitoring means is a pressure differential switch adapted to control an electric circuit.
Claim 9
Independent Claim
112 words
A method for determining the location of a liquid/liquid interface or a liquid/gas interface in a liquid-containing cavity comprising the steps of passing separate streams of gas at constant pressure by means of conduits through vertically spaced-apart outlets in the side wall of an elongated body, lowering the said elongated body into a cavity to contact any liquid therein, the said liquid restricting the flow of gas from said outlets, monitoring the gas pressure in said conduits to register any change in gas pressure between the conduits as the elongated body contacts the cavity liquid and observing the depth at which the elongated body is positioned when such pressure difference is observed.
Claim 10
Independent Claim
112 words
A method for determining the location of a liquid/liquid interface or a liquid/gas interface in a liquid-containing cavity comprising the steps of passing separate streams of gas at constant pressure by means of conduits through vertically spaced-apart outlets in the side wall of an elongated body, lowering the said elongated body into a cavity to contact any liquid therein, the said liquid restricting the flow of gas from said outlets, monitoring the gas pressure in said conduits to register any change in gas pressure between the conduits as the elongated body contacts the cavity liquid and observing the depth at which the elongated body is positioned when such pressure difference is observed.
References Cited (Backward Citations)
US3213670A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-09-14 | 1980-03-15 | 1980-09-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-09-14 | 1984-03-15 | 1984-09-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-09-14 | 1988-03-15 | 1988-09-14 | $7700.00 | Window Closed / Lapsed |