US4323334A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Two stage liquid ring pump
Assignee: Nash Engineering Co
•
Filing: 1980-01-25
•
Granted: 1982-04-06
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Expires: 2000-01-25
Abstract
Abstract Discharge or unloading orifices are provided in both stages of the two stage pump to bleed seal liquid under various vacuum conditions and to render the pump immune to the effects of variation in rotor speed and in the delivery rate of seal liquid.
Inventors
- 👤 Harold K. Haavik
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 14:17
CPC Classifications
F; F04; F04C; F04C19/00; F04C19/004
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
148 words
In a two-stage liquid ring pump including (1) first and second stages, each stage including (a) a casing, (b) a rotor disposed within the casing, (c) an intake port communicating with an intake stroke area within the casing, and (d) a discharge port communicating with a discharge stroke area within the casing, and (2) interstage conduit means connecting the first stage discharge port to the second stage intake port, the improvement comprising: a seal liquid unloader orifice in the first stage casing adjacent the first stage discharge stroke area and disposed so that the unloader orifice is normally covered by the ring of seal liquid in the first stage; and seal liquid conduit means communicating with the unloader orifice outside the first stage casing, the seal liquid conduit means communicating with the second stage discharge port and being maintained at the pressure of the second stage discharge port.
Claim 2
Dependent Claim
148 words
In a two-stage liquid ring pump including (1) first and second stages, each stage including (a) a casing, (b) a rotor disposed within the casing, (c) an intake port communicating with an intake stroke area within the casing, and (d) a discharge port communicating with a discharge stroke area within the casing, and (2) interstage conduit means connecting the first stage discharge port to the second stage intake port, the improvement comprising: a seal liquid unloader orifice in the first stage casing adjacent the first stage discharge stroke area and disposed so that the unloader orifice is normally covered by the ring of seal liquid in the first stage; and seal liquid conduit means communicating with the unloader orifice outside the first stage casing, the seal liquid conduit means communicating with the second stage discharge port and being maintained at the pressure of the second stage discharge port.
Claim 3
Dependent Claim
35 words
A pump as claimed in claim 1 wherein said unloader orifice of said first stage is disposed at an angular location of between 215° and 250° from the land in the direction of rotor rotation.
Claim 4
Dependent Claim
22 words
A pump as claimed in claim 2 wherein said unloader orifice is disposed close to the periphery of the first stage rotor.
Claim 5
Dependent Claim
41 words
A pump as claimed in claim 2 wherein said unloader orifice of said first stage is disposed at about 230° from the land in the direction of rotor rotation and close to the peripheral edge of the first stage pump rotor.
Claim 6
Dependent Claim
22 words
A pump as claimed in claim 1 wherein said unloader orifice is disposed close to the periphery of the first stage rotor.
Claim 7
Dependent Claim
49 words
A pump as claimed in claim 1 wherein the improvement further comprises a seal liquid unloader orifice in the second stage casing, said second stage unloader orifice being disposed within an angular location including the intake stroke area and close to the periphery of the second stage pump casing.
Claim 8
Dependent Claim
20 words
A pump as claimed in claim 6 wherein the second stage unloader orifice communicates with the seal liquid conduit means.
Claim 9
Dependent Claim
27 words
A pump as claimed in claim 7 wherein the first and second stage unloader orifices are normally covered by seal liquid in the seal liquid conduit means.
Claim 10
Dependent Claim
32 words
The liquid ring pump of claim 1 in which the portion of the seal liquid conduit means adjacent the unloader orifice is continually flooded with seal liquid during operation of the pump.
References Cited (Backward Citations)
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Cited
GB691425A
Cited
FR1037582A
Cited
DE823170C
Cited
GB858422A
Cited
DE1116339B
Cited
US3108738A
Cited
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Cited
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Cited
US3721508A
Cited
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Cited
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Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1985-04-05 | 1985-10-05 | 1986-04-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-04-05 | 1989-10-05 | 1990-04-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-04-05 | 1993-10-05 | 1994-04-06 | $7700.00 | Window Closed / Lapsed |