Patent US4025845A successfully refreshed from Google Patents.
US4025845A
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US
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System with photocouplers for automatic checking of operating thyristors
Assignee: GENERALE DE CONSTRUCTIONS ELECTRIQUES ET MECANIQUES(ALSTHOM) Ste
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Filing: 1975-12-31
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Granted: 1977-05-24
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Expires: 1995-12-31
Abstract
Abstract Device for the automatic checking of operating thyristors making it possible to check clearly the good condition of thyristors. It comprises photocouplers connected with resistors, arranged in parallel with a group of thyristors. The outputs of the photocouplers are grouped two by two to form a differential information. Applications: Railway or underground railway equipment.
Inventors
- 👤 Robert Lhommelet
- 👤 Jean-Paul Raynal
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 08:14
CPC Classifications
H; H02; H02H; H02H7/00; H02H7/10; H02H7/12
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
152 words
A device for automatic checking of operating thyristors comprising: current supply source with terminals; a plurality of networks connected in series between said terminals, each network comprising a thyristor and a series combination of a resistor and a first light emitting diode, said combination being in parallel with the said thyristor, the direction of conduction of said first light emitting diode being the same as that of said thyristor; a plurality of first photosensitive elements, each element having a pair of outputs and associated with a respective one of said first diodes; a second light emitting diode for each network and a second photosensitive element associated with said second light emitting diode, said second light emitting diode being connected in antiparallel configuration with the said first light emitting diode; and means for grouping the outputs of said photosensitive elements two by two to provide information indicative of the state of said thyristors.
Claim 2
Independent Claim
152 words
A device for automatic checking of operating thyristors comprising: current supply source with terminals; a plurality of networks connected in series between said terminals, each network comprising a thyristor and a series combination of a resistor and a first light emitting diode, said combination being in parallel with the said thyristor, the direction of conduction of said first light emitting diode being the same as that of said thyristor; a plurality of first photosensitive elements, each element having a pair of outputs and associated with a respective one of said first diodes; a second light emitting diode for each network and a second photosensitive element associated with said second light emitting diode, said second light emitting diode being connected in antiparallel configuration with the said first light emitting diode; and means for grouping the outputs of said photosensitive elements two by two to provide information indicative of the state of said thyristors.
Claim 3
Dependent Claim
80 words
A device for automatic checking of thyristors according to claim 1, including first outputs of first photosensitive elements connected together and to ground potential; a plurality of exclusive OR gates, second outputs of said first photosensitive elements being connected two by two to input terminals of said "exclusive OR" gates, an OR gate, output terminals of said exclusive OR gates being connected to input terminals of said gate; and alarm means actuated by an output signal of said OR gate.
Claim 4
Dependent Claim
97 words
A device for checking of thyristors, according to claim 2, including first outputs of said second photosensitive elements connected together and to ground potential; a plurality of auxiliary exclusive OR gates, second outputs of said second photosensitive elements being connected two by two to input terminals of said auxilliary exclusive OR gates, an auxiliary OR gate, output terminals of said auxiliary exclusive OR gates being connected to input terminals of said auxiliary OR gate; an output signal of said auxiliary OR gate actuating said alarm means, whose output terminal supplies the defect signal actuating an alarm device.
Claim 5
Dependent Claim
31 words
A device according to claim 3 wherein said source of current is an alternating source, said alarm means being actuated upon detection of only a short-circuit of one of said thyristors.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-05-23 | 1980-11-22 | 1981-05-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-05-23 | 1984-11-22 | 1985-05-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-05-23 | 1988-11-22 | 1989-05-24 | $7700.00 | Window Closed / Lapsed |