US3977248A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Linearizing elements for variable area flowmeter
Assignee: Fischer and Porter Co
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Filing: 1975-04-03
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Granted: 1976-08-31
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Expires: 1995-04-03
Abstract
Abstract A rotameter system adapted to produce an output indication that is linearly proportional to flow. The primary element of the system includes a float contained in a variable area tube through which flows the fluid to be measured, the float being raised or lowered in the tube as a function of flow rate, and a bar magnet mechanically coupled to the float and axially movable therewith. The secondary element of the system includes a rotatable follower magnet magnetically coupled to the bar magnet and a pointer mounted on the shaft of the follower magnet whereby the pointer sweeps from zero to maximum along a scale as the float travels from its low to its high position. A mass is eccentrically mounted on the shaft of the follower magnet, the position of the mass relative to the shaft axis being adjusted to produce a moment compensating for the non-linear relationship between flow rate and pointer movement.
Inventors
- 👤 Joseph H. Metzger
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 20:53
CPC Classifications
G; G01; G01P; G01P5/00; G01P5/02; G01F; G01F1/00; G01F1/05; G01F1/20; G01F1/22; G01F1/24; Y; Y10; Y10S; Y10S73/00; Y10S73/05
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
169 words
A rotameter system for indicating the flow rate of a fluid, said system comprising: A. a primary element including a variable area flow tube through which is flowable the fluid to be measured and having a float and a bar magnet mechanically coupled to the float which is axially movable therewith along a vertical axis, said float being lifted or lowered in the tube as a function of flow rate in accordance with a non-linear hydraulic characteristic curve; and B. a secondary element external to the variable area tube and including a rotatable follower magnet mounted on a shaft and positioned relative to the bar magnet whereby the axial movement of the bar magnet results in rotation of the follower magnet to a degree determined by the direction and extent of axial movement, and a mass eccentrically mounted on said shaft at a position relative to the axis thereof to produce a moment which compensates for said hydraulic characteristic curve whereby said rotation is linearly related to flow rate.
Claim 2
Dependent Claim
169 words
A rotameter system for indicating the flow rate of a fluid, said system comprising: A. a primary element including a variable area flow tube through which is flowable the fluid to be measured and having a float and a bar magnet mechanically coupled to the float which is axially movable therewith along a vertical axis, said float being lifted or lowered in the tube as a function of flow rate in accordance with a non-linear hydraulic characteristic curve; and B. a secondary element external to the variable area tube and including a rotatable follower magnet mounted on a shaft and positioned relative to the bar magnet whereby the axial movement of the bar magnet results in rotation of the follower magnet to a degree determined by the direction and extent of axial movement, and a mass eccentrically mounted on said shaft at a position relative to the axis thereof to produce a moment which compensates for said hydraulic characteristic curve whereby said rotation is linearly related to flow rate.
Claim 3
Dependent Claim
21 words
A system as set forth in claim 1, further including a pointer attached to said shaft and movable along a scale.
Claim 4
Dependent Claim
30 words
A system as set forth in claim 1, wherein said mass is mounted on and shiftable along a rod extending laterally from said shaft whereby the mass position is adjustable.
Claim 5
Dependent Claim
24 words
A system as set forth in claim 1, including a pointer mounted on said shaft at right angles to the axis of said mass.
Claim 6
Dependent Claim
159 words
In a system in which a variable is measured by an element which is lifted and lowered in a range extending from a zero to a maximum position, the relationship between the magnitude of the variable and the position of the element having essentially a bowed characteristic curve, said system comprising: A. a primary element including an axially movable bar magnet which is lifted or lowered in accordance with said bowed characteristic curve, B. a secondary element incuding a rotatable follower magnet mounted on a shaft and positioned relative to the bar magnet whereby the axial movement of the bar magnet results in rotation of the follower magnet to a degree determined by the direction and extent of axial movement, and a mass eccentrically mounted on said shaft at a position relative to the axis thereof to produce a moment which compensates for said bowed characteristic, whereby said rotation acquires a linear characteristic with respect to the measured variable.
Claim 7
Dependent Claim
159 words
In a system in which a variable is measured by an element which is lifted and lowered in a range extending from a zero to a maximum position, the relationship between the magnitude of the variable and the position of the element having essentially a bowed characteristic curve, said system comprising: A. a primary element including an axially movable bar magnet which is lifted or lowered in accordance with said bowed characteristic curve, B. a secondary element incuding a rotatable follower magnet mounted on a shaft and positioned relative to the bar magnet whereby the axial movement of the bar magnet results in rotation of the follower magnet to a degree determined by the direction and extent of axial movement, and a mass eccentrically mounted on said shaft at a position relative to the axis thereof to produce a moment which compensates for said bowed characteristic, whereby said rotation acquires a linear characteristic with respect to the measured variable.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-08-31 | 1980-03-01 | 1980-08-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-08-31 | 1984-03-01 | 1984-08-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-08-31 | 1988-03-01 | 1988-08-31 | $7700.00 | Window Closed / Lapsed |