Patent US4442479A successfully refreshed from Google Patents.
US4442479A
Expired / Lapsed
US
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Inverter with saturable reactor protection circuit
Assignee: Kemppi Oy
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Filing: 1982-02-02
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Granted: 1984-04-10
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Expires: 2002-02-02
Abstract
Abstract An improved D-C to A-C inverter circuit is provided including push-pull sequentially activated thyristor switches connected across a center-tapped D-C voltage source with a saturable reactor connected in series between each thyristor and the center-tap return branch and at least one saturable reactor connected in the center-tap return branch to effectively reduce peak operating voltages.
Inventors
- 👤 Tapani Makimaa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 21:24
CPC Classifications
H; H02; H02M; H02M7/00; H02M7/42; H02M7/44; H02M7/48; H02M7/505; H02M7/515; H02M7/523; H02M7/5233; H02M7/5236
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
117 words
An inverter circuit comprising a DC voltage source provided with a center tap in the source itself or in a voltage divider circuit connected across the source; two thyristor switches connected in series in the forward direction across the DC voltage source; two RC protection circuits, each one being connected across one of the thyristors, respectively; two commutation diodes, each one being connected antiparallel with one of the thyristors, respectively; and two reactors, each one being saturable and connected in series with one of the thyristors, respectively, a center branch branching out from a point between the thyristor switches to said center tap, said center branch including at least one capacitor and at least one saturable reactor.
Claim 2
Dependent Claim
117 words
An inverter circuit comprising a DC voltage source provided with a center tap in the source itself or in a voltage divider circuit connected across the source; two thyristor switches connected in series in the forward direction across the DC voltage source; two RC protection circuits, each one being connected across one of the thyristors, respectively; two commutation diodes, each one being connected antiparallel with one of the thyristors, respectively; and two reactors, each one being saturable and connected in series with one of the thyristors, respectively, a center branch branching out from a point between the thyristor switches to said center tap, said center branch including at least one capacitor and at least one saturable reactor.
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) | 1987-04-10 | 1987-10-10 | 1988-04-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-04-10 | 1991-10-10 | 1992-04-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-04-10 | 1995-10-10 | 1996-04-10 | $7700.00 | Window Closed / Lapsed |