US3781638A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Power supply including inverter having multiple-winding transformer and control transistor for controlling main switching transistors and providing overcurrent protection
Assignee: General Electric Co
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Filing: 1972-06-28
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Granted: 1973-12-25
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Expires: 1992-06-28
Abstract
Abstract A power supply includes a high frequency inverter comprising a pair of main switching transistors for alternately conducting current from a d.c. source through different winding halves of a multi-winding transformer. A starting resistor, connected between the source and the base of a selected one of the main transistors, initiates base-emitter current flow to make the transistor conductive. A control transistor turns the then conducting main transistor ''''off'''' in response to a predetermined current level through the conducting main transistor; the predetermined current level having been reached in response to the onset of magnetic saturation of the core of the transformer. Subsequently, a voltage induced in a third transformer winding initiates base-emitter current flow in the other main transistor thereby turning it ''''on''''. Also, the control transistor serves to turn either main switching transistor ''''off'''' when the current therethrough is excessive, (e.g., overload or short-circuit condition).
Inventors
- 👤 T Anderson
- 👤 J Walden
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 06:14
CPC Classifications
H; H02; H02M; H02M5/00; H02M5/40; H02M5/42; H02M5/44; H02M5/453; H02M5/458; H02M3/00; H02M3/22; H02M3/24; H02M3/28; H02M3/325; H02M3/335; H02M3/338; H02M3/3385; H02M3/3387; H02M3/3388
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
274 words
An inverter, adapted for being energized from a dc source having two terminals between which there is a potential difference, comprising: a transformer including a magnetic core on which there is wound a primary winding having a center tap to which one of said two terminals is connectable and two ends, a secondary winding adapted for having an electrical load coupled therewith and a tertiary winding; first and second transistors, each having a collector, emitter and base, said collectors of said first and second transistors being connected to different ones of said two ends of said primary winding; first impedance means connected between said center tap and said base of said first transistor; a third tranSistor having a base, collector and emitter, said emitter of said third transistor being adapted for having the other of said two terminals connected thereto, said base of said third transistor being connected to said emitters of said first and second transistors; second impedance means connected in series with tertiary winding, the serially connected tertiary winding and second impedance means being connected between the bases of said first and second transistors; first and second diodes, said first diode being connected between said bases of said second and third transistors, said second diode being connected between said bases of said first and third transistors; third and fourth diodes, said third diode being connected between said base of said first transistor and said collector of said third transistor, said fourth diode being connected between said base of said second transistor and said collector of said third transistor; third impedance means connected between said base and said emitter of said third transistor.
Claim 2
Dependent Claim
274 words
An inverter, adapted for being energized from a dc source having two terminals between which there is a potential difference, comprising: a transformer including a magnetic core on which there is wound a primary winding having a center tap to which one of said two terminals is connectable and two ends, a secondary winding adapted for having an electrical load coupled therewith and a tertiary winding; first and second transistors, each having a collector, emitter and base, said collectors of said first and second transistors being connected to different ones of said two ends of said primary winding; first impedance means connected between said center tap and said base of said first transistor; a third tranSistor having a base, collector and emitter, said emitter of said third transistor being adapted for having the other of said two terminals connected thereto, said base of said third transistor being connected to said emitters of said first and second transistors; second impedance means connected in series with tertiary winding, the serially connected tertiary winding and second impedance means being connected between the bases of said first and second transistors; first and second diodes, said first diode being connected between said bases of said second and third transistors, said second diode being connected between said bases of said first and third transistors; third and fourth diodes, said third diode being connected between said base of said first transistor and said collector of said third transistor, said fourth diode being connected between said base of said second transistor and said collector of said third transistor; third impedance means connected between said base and said emitter of said third transistor.
Claim 3
Dependent Claim
17 words
The inverter, according to claim 1, wherein said first, second and third impedance means are resistance elements.
Claim 4
Dependent Claim
50 words
The inverter, according to claim 1, wherein said first diode, said second impedance means, said tertiary winding and said base and emitter of said first transistor form a closed series circuit for maintaining base-emitter current flow in the first transistor due to an induced voltage developed in said tertiary winding.
Claim 5
Dependent Claim
50 words
The inverter, according to claim 3, wherein said second diode, said tertiary winding, said second impedance means and said base and emitter of said second transistor form a closed series circuit for maintaining base-emitter current flow in said second transistor due to an induced voltage developed in said tertiary winding.
Claim 6
Dependent Claim
41 words
The inverter, according to claim 4, wherein current is diverted through said third diode from the base-emitter path of said first transistor and directed through the collector and emitter of said third transistor when said first and third transistors are conductive.
Claim 7
Dependent Claim
42 words
The inverter, according to claim 5, wherein current is diverted through said fourth diode from the base-emitter path of said second transistor and directed through the collector and the emitter of said third transistor when said second and third transistors are conductive.
Claim 8
Dependent Claim
39 words
The inverter, according to claim 6, wherein current flow of a predetermined magnitude through the emitter of either said first transistor or said second transistor develops a voltage across said third impedance means for making said third transistor conductive.
Claim 9
Dependent Claim
51 words
The inverter, according to claim 7, wherein current of a predetermined magnitude through said primary winding begins to saturate said magnetic core whereby increased current flows in the emitter of either said first or second transistor and develops a voltage across said third impedance means to make said third transistor conductive.
Claim 10
Dependent Claim
30 words
The inverter, according to claim 6, wherein current of a predetermined magnitude through said primary winding develops a voltage across said third impedance means to make said third transistor conductive.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-12-24 | 1977-06-25 | 1977-12-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-12-24 | 1981-06-25 | 1981-12-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-12-24 | 1985-06-25 | 1985-12-25 | $7700.00 | Window Closed / Lapsed |