US3087430A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Differential pressure control system for centrifugal pumps
Assignee: Individual
•
Filing: 1959-08-12
•
Granted: 1963-04-30
•
Expires: 1979-08-12
Abstract
No abstract record available.
Inventors
- 👤 David E Griswold
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 07:31
CPC Classifications
G; G05; G05D; G05D16/00; G05D16/14; G05D16/16; G05D16/163
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
120 words
A CONTROL SYSTEM FOR MAINTAINING A CONSTANT PRESSURE DIFFERENTIAL ACROSS A CENTRIFUGAL PUMP, COMPRISING: A PIPE SYSTEM TO WHICH A FLUID MAY BE SUPPLIED AT A VARIABLE PRESSURE AND FROM WHICH FLUID MAY BE DRAWN AT A VARIABLE RATE, A CENTRIFUGAL TYPE PUMP, HAVING AN INLET AND AN OUTLET, CONNECTED WITH SAID PIPE SYSTEM; AND MEANS TO MAINTAIN A CONSTANT PRESSURE DIFFERENTIAL ACROSS SAID PUMP, SAID MEANS INCLUDING A FLOW REGULATING MAIN VALVE OPERABLE BETWEEN CLOSED AND FULLY OPENED POSITIONS CONNECTED IN SAID SYSTEM DOWNSTREAM OF SAID PUMP AND ARRANGED SO THAT THE DISCHARGE PRESSURE OF SAID PUMP TENDS TO OPEN SAID VALVE, AND MEANS RESPONSIVE TO THE PRESSURE DIFFERENTIAL ACROSS SAID PUMP CONTROLLING THE OPERATION OF SAID MAIN VALVE.
Claim 2
Dependent Claim
120 words
A CONTROL SYSTEM FOR MAINTAINING A CONSTANT PRESSURE DIFFERENTIAL ACROSS A CENTRIFUGAL PUMP, COMPRISING: A PIPE SYSTEM TO WHICH A FLUID MAY BE SUPPLIED AT A VARIABLE PRESSURE AND FROM WHICH FLUID MAY BE DRAWN AT A VARIABLE RATE, A CENTRIFUGAL TYPE PUMP, HAVING AN INLET AND AN OUTLET, CONNECTED WITH SAID PIPE SYSTEM; AND MEANS TO MAINTAIN A CONSTANT PRESSURE DIFFERENTIAL ACROSS SAID PUMP, SAID MEANS INCLUDING A FLOW REGULATING MAIN VALVE OPERABLE BETWEEN CLOSED AND FULLY OPENED POSITIONS CONNECTED IN SAID SYSTEM DOWNSTREAM OF SAID PUMP AND ARRANGED SO THAT THE DISCHARGE PRESSURE OF SAID PUMP TENDS TO OPEN SAID VALVE, AND MEANS RESPONSIVE TO THE PRESSURE DIFFERENTIAL ACROSS SAID PUMP CONTROLLING THE OPERATION OF SAID MAIN VALVE.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1966-04-29 | 1966-10-29 | 1967-04-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1970-04-29 | 1970-10-29 | 1971-04-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1974-04-29 | 1974-10-29 | 1975-04-30 | $7700.00 | Window Closed / Lapsed |