US4729236A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Automatic orifice calibrator
Assignee: United States Department of the Army
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Filing: 1986-12-12
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Granted: 1988-03-08
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Expires: 2006-12-12
Abstract
Abstract An orifice is calibrated by passing air through the orifice and into a tubearrying a water column. The rate at which the water in the water column falls due to the passage of air through the orifice is measured to find the volumetric flow and elapsed time of air passing through the orifice. A computer is then used to subject the volumetric flow and elapsed time data to a regression analysis to produce an equation of displacement as a function of elapsed time. The first derivative of this equation is the flow rate. A correlation coefficient of the equation is printed, and the volumetric and mass flow rates may be printed if desired.
Inventors
- 👤 Andrew M. Samborsky
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 16:53
CPC Classifications
G; G01; G01F; G01F25/00; G01F25/10; G01F25/17; G01F23/00; G01F23/30; G01F23/64; G01F23/72; G01M; G01M3/00; G01M3/007
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
99 words
A method of calibrating an orifice, comprising passing a gas through the orifice into a column of liquid in a tube and measuring the time it takes for a specific volume and head pressure to occur in the tube, maintaining equality between a vacuum head and the liquid level in the tube, measuring the time for the liquid level changes in the tube, and the volumetric flow of gas into the tube, and applying regression analysis of the volumetric flow with time to form a characteristic parabolic curve, whose first derivative is the flow rate characteristic of the orifice.
Claim 2
Independent Claim
99 words
A method of calibrating an orifice, comprising passing a gas through the orifice into a column of liquid in a tube and measuring the time it takes for a specific volume and head pressure to occur in the tube, maintaining equality between a vacuum head and the liquid level in the tube, measuring the time for the liquid level changes in the tube, and the volumetric flow of gas into the tube, and applying regression analysis of the volumetric flow with time to form a characteristic parabolic curve, whose first derivative is the flow rate characteristic of the orifice.
Claim 3
Dependent Claim
40 words
A method according to claim 1, including defining a plurality of levels for the liquid in the tube and measuring the elapsed time it takes for the liquid level to pass each tube level to measure the volumetric flow rate.
Claim 4
Dependent Claim
23 words
A method according to claim 2, including sensing the passage of a magnetic float on the liquid level for detecting the liquid level.
Claim 5
Dependent Claim
37 words
A method according to claim 2, including using a computer to apply the regression analysis, the computer receiving the signals corresponding to the measured vacuum pressure and to the measured time at which the liquid level falls.
Claim 6
Independent Claim
164 words
An apparatus for calibrating an orifice comprising a liquid column having a lower end for insertion into a liquid and an upper end, a flow tube connected to said upper end of said column tube and defining a flow passage, valve means at an end of said flow tube remote from said column tube for selectively admitting gas into said flow tube to pass through said flow passage, a pressure transducer in said flow tube between said orifice holder and said column tube for measuring a vacuum head pressure in said column tube, liquid level sensing means operatively connected to said column tube for sensing the level of liquid in said column tube and computer means connected to said pressure transducer and to said liquid level sensor means, said computer having timing means for timing the successive liquid levels in said column tube and for calculating a parabolic characteristic curve using regression analysis which is characteristic of an orifice held by said orifice holder.
Claim 7
Independent Claim
164 words
An apparatus for calibrating an orifice comprising a liquid column having a lower end for insertion into a liquid and an upper end, a flow tube connected to said upper end of said column tube and defining a flow passage, valve means at an end of said flow tube remote from said column tube for selectively admitting gas into said flow tube to pass through said flow passage, a pressure transducer in said flow tube between said orifice holder and said column tube for measuring a vacuum head pressure in said column tube, liquid level sensing means operatively connected to said column tube for sensing the level of liquid in said column tube and computer means connected to said pressure transducer and to said liquid level sensor means, said computer having timing means for timing the successive liquid levels in said column tube and for calculating a parabolic characteristic curve using regression analysis which is characteristic of an orifice held by said orifice holder.
Claim 8
Dependent Claim
44 words
A device according to claim 5 wherein said liquid level sensor means comprises a magnetic float for floating on a liquid level in said column tube and a plurality of magnetic pickups distributed along said tube column for sensing the passage of said float.
References Cited (Backward Citations)
US4331262A
Cited
US4501972A
Cited
US4502318A
Cited
US4509371A
Cited
US4590790A
Cited
US4645174A
Cited
US4671109A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-03-08 | 1991-09-07 | 1992-03-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-03-08 | 1995-09-07 | 1996-03-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-03-08 | 1999-09-07 | 2000-03-08 | $7700.00 | Window Closed / Lapsed |