US3222587A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Alternating current converting circuit
Assignee: Ampex Corp
•
Filing: 1961-03-14
•
Granted: 1965-12-07
•
Expires: 1981-03-14
Abstract
No abstract record available.
Inventors
- 👤 Lichowsky Abraham
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 12:46
CPC Classifications
H; H02; H02M; H02M7/00; H02M7/42; H02M7/44; H02M7/48; H02M7/505; H02M7/515; H02M7/5152; H02M1/00; H02M1/08
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
126 words
A CIRCUIT FOR TRANSFORMING A D.C. VOLTAGE TO AN A.C. VOLTAGE OF CONTROLLABLE FREQUENCY FOR DRIVING A MOTOR COMPRISING FOUR SILICON CONTROLLED RECTIFIERS CONNECTED IN A BRIDGE CIRCUIT, MEANS CONNECTING A FIRST PAIR OF TERMINALS OF THE BRIDGE CIRCUIT TO A SOURCE OF DIRECT VOLTAGE, MEANS CONNECTING A SECOND PAIR OF TERMINALS OF THE BRIDGE CIRCUIT TO A MOTOR, MEANS FOR TRIGGERING RESPECTIVE OPPOSED PAIRS OF SAID SILICON CONTROLLED RECTIFIERS TO CONDUCT IN ALTERNATE SEQUENCE, MEANS FOR EXTINGUISHING CONDUCTION IN THE SILICON CONTROLLED RECTIFIERS AT SELECTED INTERVALS IN ORDER TO APPLY A SIGNAL WAVE TO THE MOTOR OF A SELECTED FUNDAMENTAL FREQUENCY WHICH IS SUBSTANTIALLY FREE OF EVEN HARMONICS, THE THIRD HARMONIC AND INTEGRAL MULTIPLES OF THE THIRD HARMONIC, AND MEANS FOR CAUSING A SELECTED PAIR
Claim 2
Dependent Claim
126 words
A CIRCUIT FOR TRANSFORMING A D.C. VOLTAGE TO AN A.C. VOLTAGE OF CONTROLLABLE FREQUENCY FOR DRIVING A MOTOR COMPRISING FOUR SILICON CONTROLLED RECTIFIERS CONNECTED IN A BRIDGE CIRCUIT, MEANS CONNECTING A FIRST PAIR OF TERMINALS OF THE BRIDGE CIRCUIT TO A SOURCE OF DIRECT VOLTAGE, MEANS CONNECTING A SECOND PAIR OF TERMINALS OF THE BRIDGE CIRCUIT TO A MOTOR, MEANS FOR TRIGGERING RESPECTIVE OPPOSED PAIRS OF SAID SILICON CONTROLLED RECTIFIERS TO CONDUCT IN ALTERNATE SEQUENCE, MEANS FOR EXTINGUISHING CONDUCTION IN THE SILICON CONTROLLED RECTIFIERS AT SELECTED INTERVALS IN ORDER TO APPLY A SIGNAL WAVE TO THE MOTOR OF A SELECTED FUNDAMENTAL FREQUENCY WHICH IS SUBSTANTIALLY FREE OF EVEN HARMONICS, THE THIRD HARMONIC AND INTEGRAL MULTIPLES OF THE THIRD HARMONIC, AND MEANS FOR CAUSING A SELECTED PAIR
References Cited (Backward Citations)
US1896647A
Cited
US1948360A
Cited
US2147474A
Cited
US2474867A
Cited
US2912634A
Cited
US2953735A
Cited
US2987666A
Cited
US3059191A
Cited
US3109977A
Cited
US3075136A
Cited
US3041551A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1968-12-06 | 1969-06-07 | 1969-12-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1972-12-06 | 1973-06-07 | 1973-12-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1976-12-06 | 1977-06-07 | 1977-12-07 | $7700.00 | Window Closed / Lapsed |