Patent US3478532A successfully refreshed from Google Patents.
US3478532A
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Electronic head pressure control for condensing units
Assignee: FRIEDRICH Co A TX CORP
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Filing: 1964-08-05
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Granted: 1969-11-18
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Expires: 1984-08-05
Abstract
No abstract record available.
Inventors
- 👤 Thomas A Cootey
- 👤 Larry M Fischer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 07:46
CPC Classifications
G; G05; G05D; G05D23/00; G05D23/19; G05D23/20; G05D23/24; F; F28; F28B; F28B11/00; G05D23/1906; H; H02; H02P; H02P7/00; H02P7/06; H02P7/18; H02P7/24; H02P7/28; H02P7/285; H02P7/292; H02P7/293; F25; F25B; F25B2600/00; F25B2600/11; F25B2600/111; Y; Y02; Y02B; Y02B30/00; Y02B30/70
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
88 words
A CONTROL SYSTEM FOR REGULATING WITHIN PREDETERMINED LIMITS THE CONDENSING PRESSURE IN A FAN MOTOR COOLED REFRIGERANT CONDENSOR, COMPRISING: (1) SENSOR MEANS TO SENSE CHANGES IN THE TEMPERATURE OF THE CONDENSER; (2) SIGNAL GENERATING MEANS CONNECTED TO SAID SENSOR MEANS TO PRODUCE ELECTRICAL SIGNALS PROPORTIONAL TO THE TEMPERATURE OF THE CONDENSER; (3) AN OSCILLATOR CIRCUIT, CONNECTED TO AND HAVING ITS PERIOD OF OSCILLATION CONTROLLED BY SAID SIGNAL GENERATING MEANS; AND (4) SWITCHING MEANS CONNECTED TO THE FAN MOTOR AND CONNECTED TO AND CONTROLLED BY SAID OSCILLATOR SO THAT
Claim 2
Dependent Claim
88 words
A CONTROL SYSTEM FOR REGULATING WITHIN PREDETERMINED LIMITS THE CONDENSING PRESSURE IN A FAN MOTOR COOLED REFRIGERANT CONDENSOR, COMPRISING: (1) SENSOR MEANS TO SENSE CHANGES IN THE TEMPERATURE OF THE CONDENSER; (2) SIGNAL GENERATING MEANS CONNECTED TO SAID SENSOR MEANS TO PRODUCE ELECTRICAL SIGNALS PROPORTIONAL TO THE TEMPERATURE OF THE CONDENSER; (3) AN OSCILLATOR CIRCUIT, CONNECTED TO AND HAVING ITS PERIOD OF OSCILLATION CONTROLLED BY SAID SIGNAL GENERATING MEANS; AND (4) SWITCHING MEANS CONNECTED TO THE FAN MOTOR AND CONNECTED TO AND CONTROLLED BY SAID OSCILLATOR SO THAT
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) | 1972-11-17 | 1973-05-19 | 1973-11-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1976-11-17 | 1977-05-19 | 1977-11-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1980-11-17 | 1981-05-19 | 1981-11-18 | $7700.00 | Window Closed / Lapsed |