US3910112A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Flow meter
Assignee: Southwest Research Institute
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Filing: 1974-05-17
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Granted: 1975-10-07
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Expires: 1994-05-17
Abstract
Abstract A flow meter is described which provides a linear readout signal proportional to flow therethrough and which can compensate for changes in the viscosity of the fluid. The flow meter is designed for in-line installation. The working element consists of two spring-restrained pistons mounted on a common stem. One of the pistons moves axially inside a contoured cylinder providing a nonlinear area-displacement characteristic. The cylinder contour, and the nonlinear area displacement characteristic thereof, is designed to produce a linear relationship between the piston displacement and fluid flow rate. The second piston provides the viscosity-compensating correction force to give an accurate flow indication in the presence of changes of fluid viscosity. The stem upon which the pistons are mounted extends into a calibrated readout scale to provide an indication of flow rate as a function of piston displacement.
Inventors
- 👤 C Richard Gerlach
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 04:50
CPC Classifications
G; G01; G01F; G01F1/00; G01F1/05; G01F1/20; G01F1/22; G01F1/26
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
196 words
A flow meter comprising; a housing having an inlet and outlet means; a contoured cylinder in said housing with said contour being progressively outward from a small end to a large end thereof, said inlet means being in a flow relationship with said small end and said outlet means being in a flow relationship with said large end; first piston means in said contoured cylinder; a uniform cylinder in said housing and in substantially parallel alignment with said contoured cylinder; second piston means in said uniform cylinder, said second piston means attached to said first piston means for movement therewith; resilient means for urging said first piston means towards said small end of said contoured cylinder; port means through said second piston means connecting fluid in said housing to said uniform cylinder; means for measuring the movement of said first and second piston means; said first piston means being moved axially along said contoured cylinder with said movement of said first and second piston means being a linear function of said fluid flowing through said housing of said flow meter, said second piston means and said port means compensating for changes in viscosity of said fluid.
Claim 2
Dependent Claim
196 words
A flow meter comprising; a housing having an inlet and outlet means; a contoured cylinder in said housing with said contour being progressively outward from a small end to a large end thereof, said inlet means being in a flow relationship with said small end and said outlet means being in a flow relationship with said large end; first piston means in said contoured cylinder; a uniform cylinder in said housing and in substantially parallel alignment with said contoured cylinder; second piston means in said uniform cylinder, said second piston means attached to said first piston means for movement therewith; resilient means for urging said first piston means towards said small end of said contoured cylinder; port means through said second piston means connecting fluid in said housing to said uniform cylinder; means for measuring the movement of said first and second piston means; said first piston means being moved axially along said contoured cylinder with said movement of said first and second piston means being a linear function of said fluid flowing through said housing of said flow meter, said second piston means and said port means compensating for changes in viscosity of said fluid.
Claim 3
Dependent Claim
34 words
The flow meter as recited in claim 1 wherein said measuring means provides a direct means for indicating fluid flow through said flow meter, said direct indicating means being said linear function of flow.
Claim 4
Dependent Claim
29 words
The flow meter as recited in claim 2 wherein the annular area between said primary piston and said contoured cylinder varies as a square root function of piston displacement.
Claim 5
Dependent Claim
24 words
The flow meter as recited in claim 3 wherein said port means connects said uniform cylinder and said large end of said contoured cylinder.
Claim 6
Dependent Claim
26 words
The flow meter as recited in claim 3 wherein said port means connects said uniform cylinder and the leading outside surface oF said first piston means.
Claim 7
Dependent Claim
38 words
The flow meter as recited in claim 3 wherein direct indicating means is a window in said housing having a scale thereon to directly read movement of said first and second piston means in terms of flow rate.
Claim 8
Dependent Claim
27 words
The flow meter as recited in claim 6 further including a valve means for draining said uniform cylinder and filling with fluid flowing through said flow meter.
Claim 9
Dependent Claim
23 words
The flow meter as recited in claim 7 further including a stem for attaching said first piston means to said second piston means.
Claim 10
Dependent Claim
21 words
The flow meter as recited in claim 5 further includes seal means between said second piston means and said uniform cylinder.
Claim 11
Dependent Claim
48 words
The flow meter as recited in claim 9 further including a stem for attaching said first piston means to said second piston means, said port means being from said leading outside surface of said first piston means, through said stem and second piston means to said uniform cylinder.
Claim 12
Dependent Claim
48 words
The flow meter as recited in claim 10 further including a bleed valve connected to said uniform cylinder and a window having a scale thereon to visually see the movement of said first and second pistons and said stem to determine rate of flow through said flow meter.
References Cited (Backward Citations)
US2061852A
Cited
US3789664A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-10-06 | 1979-04-07 | 1979-10-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-10-06 | 1983-04-07 | 1983-10-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-10-06 | 1987-04-07 | 1987-10-07 | $7700.00 | Window Closed / Lapsed |