US3686946A
Expired / Lapsed
US
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Flow metering devices of the pressure differential producing type
Assignee: SPX Technologies Inc
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Filing: 1970-06-22
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Granted: 1972-08-29
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Expires: 1990-06-22
Abstract
Abstract Fluid flow metering devices of the pressure differential producing type comprising a tube having a converging section which guides the fluid to a throat. The internal geometry of each tube controls the velocity distribution in the flowing stream by causing the fluid, at least once, to form a vena contracta and then expand and reattach to the tube wall before reaching a static pressure-sensing tap in the throat wall. Preferably, one vena contracta is formed in the throat entrance, and at least one other vena contracta is created in the converging section. However, a single vena contracta in either location location may be used. An additional vena contracta, or several vena contractas, may also be created in the flowing stream upstream of the inlet pressure-sensing tap.
Inventors
- 👤 Dezsoe Halmi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 20:17
CPC Classifications
G; G01; G01F; G01F1/00; G01F1/05; G01F1/34; G01F1/36; G01F1/40; G01F1/44
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
165 words
A flow metering device (11, 111 or 112) of the pressure differential producing type including a. a tube having a wall which defines a throat (13, 131 or 132) and a converging section (14,141 or 142) for guiding fluid thereto from an inlet region of larger cross section, b. a pressure tap (16, 161 or 162) for sensing the pressure in the inlet region; and c. a pressure tap (17, 171 or 172) for sensing static pressure in the throat at a point where the flow is attached to the tube wall, d. the tube wall being shaped to cause the fluid passing from the inlet region to the throat pressure-sensing tap to 1. form at least one vena contracta in the converging section (14, 141 or 142) and then expand and reattach to the wall of that section, and 2. form another vena contracta in the throat (13, 131 or 132) adjacent its entrance and then to reattach to the wall of the throat.
Claim 2
Dependent Claim
165 words
A flow metering device (11, 111 or 112) of the pressure differential producing type including a. a tube having a wall which defines a throat (13, 131 or 132) and a converging section (14,141 or 142) for guiding fluid thereto from an inlet region of larger cross section, b. a pressure tap (16, 161 or 162) for sensing the pressure in the inlet region; and c. a pressure tap (17, 171 or 172) for sensing static pressure in the throat at a point where the flow is attached to the tube wall, d. the tube wall being shaped to cause the fluid passing from the inlet region to the throat pressure-sensing tap to 1. form at least one vena contracta in the converging section (14, 141 or 142) and then expand and reattach to the wall of that section, and 2. form another vena contracta in the throat (13, 131 or 132) adjacent its entrance and then to reattach to the wall of the throat.
Claim 3
Dependent Claim
24 words
form another vena contracta in the throat (13, 131 or 132) adjacent its entrance and then to reattach to the wall of the throat.
Claim 4
Dependent Claim
24 words
form another vena contracta in the throat (13, 131 or 132) adjacent its entrance and then to reattach to the wall of the throat.
Claim 5
Dependent Claim
126 words
The flow metering device (11 or 112) defined in claim 1 in which a. the throat (13 or 132) has a cylindrical wall; b. the converging section (14 or 142) includes a first conical portion (19 or 192) which intersects the cylindrical throat wall along a continuous edge (22 or 222) which causes the fluid to form said another vena contracta in the throat; c. The converging section includes a second conical portion (18 or 182) upstream of and having a larger conical angle than the first such portion (19 or 192); and d. the two conical portions intersect at a continuous edge (21, or 212) which causes the fluid to form said one vena contracta and reattach to the first conical portion (19 or 192).
Claim 6
Dependent Claim
29 words
The flow metering device (11, 111 or 112) defined in claim 1 in which the length of the throat (13, 131 or 132) is materially less than its diameter.
Claim 7
Dependent Claim
31 words
The flow metering device (11, 111 or 112) defined in claim 3 in which the length of the throat (13, 131 or 132) is on the order of one-half its diameter.
Claim 8
Dependent Claim
44 words
The flow metering device (11, 111 or 112) defined in claim 4 in which the throat pressure-sensing tap (17, 171 or 172) is located at the point (B'') where the fluid expanding from the vena contracta in the throat reattaches to the throat wall.
Claim 9
Dependent Claim
53 words
The flow metering device (111) defined in claim 1 in which the wall of the converging section (141) is shaped to cause the fluid to form a series of vena contractas and to reattach to the wall of the converging section between successive vena contractas as well as after the last vena contracta.
Claim 10
Dependent Claim
101 words
The flow metering device (111) defined in claim 1 in which a. the wall of the flow tube also defines an inlet section (121) which is joined to the throat (131) by the converging section (141); b. said inlet pressure-sensing tap (161) is a static pressure tap in the wall of the inlet section (121); and c. the wall of the inlet section (121) is shaped to cause the fluid, at least once during its passage therethrough, to form a vena contracta and then to expand and reattach to the wall of this section before reaching the inlet pressure-sensing tap (161).
Claim 11
Dependent Claim
39 words
The flow metering device (11, 111, or 112) defined in claim 1 in which the wall shape is such that the vena contracta in the throat entrance is less pronounced than any vena contracta formed in the converging section.
Claim 12
Dependent Claim
157 words
A flow metering device (11, 111, 112, 113 oR 114) of the pressure differential producing type including a. a tube having a wall which defines a throat (13, 131, 132, 133 or 134) whose length is materially less than its diameter, and a converging section (14, 141, 142, 143 or 144) for guiding fluid thereto from an inlet region of larger cross section; b. a pressure tap (16, 161, 162, 163 or 164) for sensing the pressure in the inlet region; and c. a pressure tap (17, 171, 172, 173 or 174) for sensing static pressure in the throat at a point where the flow is attached to the wall, d. the tube wall being shaped to cause the fluid, at least once during its passage from the inlet region to the throat pressure-sensing tap, to form a vena contracta and then to expand and reattach to the wall at a point downstream of the vena contracta.
Claim 13
Dependent Claim
157 words
A flow metering device (11, 111, 112, 113 oR 114) of the pressure differential producing type including a. a tube having a wall which defines a throat (13, 131, 132, 133 or 134) whose length is materially less than its diameter, and a converging section (14, 141, 142, 143 or 144) for guiding fluid thereto from an inlet region of larger cross section; b. a pressure tap (16, 161, 162, 163 or 164) for sensing the pressure in the inlet region; and c. a pressure tap (17, 171, 172, 173 or 174) for sensing static pressure in the throat at a point where the flow is attached to the wall, d. the tube wall being shaped to cause the fluid, at least once during its passage from the inlet region to the throat pressure-sensing tap, to form a vena contracta and then to expand and reattach to the wall at a point downstream of the vena contracta.
Claim 14
Dependent Claim
34 words
The flow metering device (11, 111, 112, 113 or 114) defined in claim 9 in which the throat (13, 131, 132, 133, or 134) has a length on the order of one-half its diameter.
Claim 15
Dependent Claim
104 words
The flow metering device (11, 112 or 114) defined in claim 9 in which a. the throat (13, 132 or 134) has a cylindrical wall; b. the wall of the converging section (14, 142 or 144) includes a conical portion (19, 192or 194) which intersects the cylindrical wall along a continuous edge (22, 222 or 2224) which causes the fluid to form a vena contracta in the throat (13, 132 or 134) and then reattach to the throat wall; and c. the throat pressure-sensing tap (17, 172 or 174) is located at the point (B'') at which the fluid reattaches to the throat wall.
Claim 16
Dependent Claim
81 words
The flow metering device (113) defined in claim 9 in which a. the throat (133) has a cylindrical wall; b. the converging portion (143) includes a conical upstream portion (183) and a smoothly curved downstream portion (193); c. the two portions (183,193) intersect at a continuous edge (213) which causes the fluid to form a vena contracta and reattach to the downstream portion (193); and d. the downstream portion (193) is joined smoothly to the cylindrical wall (133) of the throat.
References Cited (Backward Citations)
GB198691A
Cited
US2217668A
Cited
US2284013A
Cited
US2842962A
Cited
US2868013A
Cited
GB1089203A
Cited
GB1018396A
Cited
GB1047280A
Cited
US3273390A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-08-29 | 1976-02-28 | 1976-08-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-08-29 | 1980-02-28 | 1980-08-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-08-29 | 1984-02-28 | 1984-08-29 | $7700.00 | Window Closed / Lapsed |