Patent US3714467A successfully refreshed from Google Patents.
US3714467A
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Chopper circuit
Assignee: Hitachi Ltd
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Filing: 1971-03-29
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Granted: 1973-01-30
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Expires: 1991-03-29
Abstract
Abstract A chopper circuit comprising a first compound thyristor with a first series saturable reactor mainly for conducting load current and a commutation circuit storing the commutation energy for commutating the first thyristor by igniting a second thyristor, the construction of the junction in these two thyristors consisting of a thyristor included in this circuit with a second series saturable reactor region and a diode region in reverse parallel connection and one common junction and saturable reactors connected to said thyristors in series.
Inventors
- 👤 T Tuboi
- 👤 T Takahashi
- 👤 S Kariya
- 👤 H Narita
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 20:42
CPC Classifications
H; H03; H03K; H03K17/00; H03K17/51; H03K17/56; H03K17/72; H03K17/73; H02; H02M; H02M1/00; H02M1/06; H02M3/00; H02M3/02; H02M3/04; H02M3/10; H02M3/125; H02M3/135; H10; H10D; H10D99/00
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
141 words
A chopper circuit comprising first compound thyristor means having a thyristor region and a diode region in reverse parallel connection as one body in which one of the junctions of the thyristor region comprising three junctions is extended to the diode region so as to function as a junction of the diode region; first saturable reactor means connected in series circuit with said first compound thyristor means; second compound thyristor means having the same structure as said first compound thyristor means and being connected to said first saturable reactor means; condenser means for commutating said first compound thyristor means by applying energy stored therein to the series circuit of said first compound thyristor means and said first saturable reactor means upon ignition of said second thyristor means; and second saturable reactor means connected in series with said second compound thyristor means.
Claim 2
Dependent Claim
141 words
A chopper circuit comprising first compound thyristor means having a thyristor region and a diode region in reverse parallel connection as one body in which one of the junctions of the thyristor region comprising three junctions is extended to the diode region so as to function as a junction of the diode region; first saturable reactor means connected in series circuit with said first compound thyristor means; second compound thyristor means having the same structure as said first compound thyristor means and being connected to said first saturable reactor means; condenser means for commutating said first compound thyristor means by applying energy stored therein to the series circuit of said first compound thyristor means and said first saturable reactor means upon ignition of said second thyristor means; and second saturable reactor means connected in series with said second compound thyristor means.
Claim 3
Dependent Claim
141 words
A chopper circuit comprising first compound thyristor means having a thyristor region and a diode region in reverse parallel connection as one body in which one of the junctions of the thyristor region comprising three junctions is extended to the diode region so as to function as a junction of the diode region; first saturable reactor means connected in series circuit with said first compound thyristor means; second compound thyristor means having the same structure as said first compound thyristor means and being connected to said first saturable reactor means; condenser means for commutating said first compound thyristor means by applying energy stored therein to the series circuit of said first compound thyristor means and said first saturable reactor means upon ignition of said second thyristor means; and second saturable reactor means connected in series with said second compound thyristor means.
Claim 4
Dependent Claim
141 words
A chopper circuit comprising first compound thyristor means having a thyristor region and a diode region in reverse parallel connection as one body in which one of the junctions of the thyristor region comprising three junctions is extended to the diode region so as to function as a junction of the diode region; first saturable reactor means connected in series circuit with said first compound thyristor means; second compound thyristor means having the same structure as said first compound thyristor means and being connected to said first saturable reactor means; condenser means for commutating said first compound thyristor means by applying energy stored therein to the series circuit of said first compound thyristor means and said first saturable reactor means upon ignition of said second thyristor means; and second saturable reactor means connected in series with said second compound thyristor means.
Claim 5
Dependent Claim
41 words
A chopper circuit according to claim 1, wherein the time for saturating from one saturated value to the other in the first and second saturable reactor means is selected to be more than the time required to recover the diode region.
Claim 6
Dependent Claim
32 words
A chopper circuit according to claim 1, wherein said first and second saturable reactor means are respectively provided as parallel impedance means which increase the exciting magnetromotive force for saturating the cores.
Claim 7
Dependent Claim
19 words
A chopper circuit according to claim 3, wherein resistors having predetermined resistance value are used as said impedance means.
Claim 8
Dependent Claim
21 words
A chopper circuit according to claim 3, wherein nonsaturable reactors having a predetermined inductance value are used as said impedance means.
Claim 9
Dependent Claim
48 words
A chopper circuit according to claim 1, wherein said first compound thyristor means comprises plural compound thyristors connected in parallel and current balancer means for balancing the current of the respective thyristors, said first saturable reactor means being connected with the common connection point of said current balancer.
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) | 1976-01-30 | 1976-07-31 | 1977-01-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-01-30 | 1980-07-31 | 1981-01-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-01-30 | 1984-07-31 | 1985-01-30 | $7700.00 | Window Closed / Lapsed |