Patent US3275948A successfully refreshed from Google Patents.
US3275948A
Expired / Lapsed
US
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Inverter with d.c. frequency control
Assignee: Forbro Design Corp
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Filing: 1964-03-09
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Granted: 1966-09-27
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Expires: 1984-03-09
Abstract
No abstract record available.
Inventors
- 👤 Rosenbusch Franklin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 19:54
CPC Classifications
H; H03; H03K; H03K3/00; H03K3/02; H03K3/26; H03K3/30; H02; H02M; H02M7/00; H02M7/42; H02M7/44; H02M7/48; H02M7/53; H02M7/537; H02M7/5383; H02M7/53832; H02M7/53835
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
105 words
IN A DIRECT CURRENT TO ALTERNATING CURRENT INVERTER, THE COMBINATION OF, A SATURABLE CORE, A SOURCE OF DIRECT CURRENT, A MAIN WINDING ON SAID CORE, A FEED-BACK WINDING ON SAID CORE, A PAIR OF TRANSISTORS CONNECTED TO COUPLE SAID SOURCE OF DIRECT CURRENT WITH SAID WINDINGS ADAPTED TO PROVIDE AN OSCILLATING CIRCUIT, A THIRD WINDINGS COUPLED TO SAID CORE FOR PROVIDING AN OUTPUT ALTERNATING CURRENT TO UTILIZATION MEANS, A FOURTH WINDING ON SAID CORE, RECTIFYING MEANS AND CURRENT CONTROL MEANS CONNECTED TO SAID MAIN WINDING AND ADAPTED TO SUPPLY A CONTROLLED DIRECT CURRENT TO SAID FOURTH WINDING FOR STABILIZING THE FREQUENCY OF SAID OSCILLATING CIRCUIT.
Claim 2
Dependent Claim
105 words
IN A DIRECT CURRENT TO ALTERNATING CURRENT INVERTER, THE COMBINATION OF, A SATURABLE CORE, A SOURCE OF DIRECT CURRENT, A MAIN WINDING ON SAID CORE, A FEED-BACK WINDING ON SAID CORE, A PAIR OF TRANSISTORS CONNECTED TO COUPLE SAID SOURCE OF DIRECT CURRENT WITH SAID WINDINGS ADAPTED TO PROVIDE AN OSCILLATING CIRCUIT, A THIRD WINDINGS COUPLED TO SAID CORE FOR PROVIDING AN OUTPUT ALTERNATING CURRENT TO UTILIZATION MEANS, A FOURTH WINDING ON SAID CORE, RECTIFYING MEANS AND CURRENT CONTROL MEANS CONNECTED TO SAID MAIN WINDING AND ADAPTED TO SUPPLY A CONTROLLED DIRECT CURRENT TO SAID FOURTH WINDING FOR STABILIZING THE FREQUENCY OF SAID OSCILLATING CIRCUIT.
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) | 1969-09-26 | 1970-03-28 | 1970-09-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1973-09-26 | 1974-03-28 | 1974-09-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1977-09-26 | 1978-03-28 | 1978-09-27 | $7700.00 | Window Closed / Lapsed |