US3600635A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Protection circuit including a thyristor and a three terminal device
Assignee: RCA Corp
•
Filing: 1969-07-15
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Granted: 1971-08-17
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Expires: 1989-07-15
Abstract
Abstract A three terminal device containing a pair of mechanical contacts is placed in circuit with a thyristor and a load to be supplied; the mechanical contacts are adapted to respond to the current supplied to the load to determine the presence or absence of a triggering signal at the control electrode of the thyristor.
Inventors
- 👤 John Manning Savidge Neilson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 10:36
CPC Classifications
H; H02; H02H; H02H3/00; H02H3/08; H02H3/085; H01; H01H; H01H9/00; H01H9/54; H01H9/547
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
145 words
A protection circuit connected to a source of power and adapted to sense overload conditions of a first load and for rendering a second load operative for relieving said overload conditions, comprising: a thyristor having first and second main electrodes and a control electrode, the main electrodes of said thyristor being connected in series circuit with said second load and said source, said first load being connected in parallel circuit with said thyristor and said second load; a three terminal device connected in circuit with said source and said first load, said device adapted to sense the current supplied to said first load via two terminals thereof and to permit or prevent the application of a triggering signal to the control electrode of said thyristor via the third terminal of said device in accordance with the magnitude of the current supplied to said first load.
Claim 2
Dependent Claim
145 words
A protection circuit connected to a source of power and adapted to sense overload conditions of a first load and for rendering a second load operative for relieving said overload conditions, comprising: a thyristor having first and second main electrodes and a control electrode, the main electrodes of said thyristor being connected in series circuit with said second load and said source, said first load being connected in parallel circuit with said thyristor and said second load; a three terminal device connected in circuit with said source and said first load, said device adapted to sense the current supplied to said first load via two terminals thereof and to permit or prevent the application of a triggering signal to the control electrode of said thyristor via the third terminal of said device in accordance with the magnitude of the current supplied to said first load.
Claim 3
Dependent Claim
68 words
A protection circuit as defined in claim 1 wherein said three terminal device includes a pair of mechanical contacts in series with the third terminal thereof, said pair of contacts having an opened and a closed position, the position of said contacts being responsive to the current supplied to the load to determine the presence of absence of a triggering signal at the control electrode of said thyristor.
Claim 4
Dependent Claim
14 words
A protection circuit as defined in claim 2 wherein said contacts are thermally operated.
Claim 5
Dependent Claim
14 words
A protection circuit as defined in claim 2 wherein said contacts are magnetically operated.
Claim 6
Dependent Claim
92 words
A protection circuit as defined in claim 2 wherein said three terminal device comprises a bimetallic strip intermediate said first and second terminals thereof and a pair of mechanical contacts, one of said contacts connected to said bimetallic strip and the other of said contacts connected to said third terminal, the deflection of said bimetallic strip caused by a current flow therethrough above a particular magnitude operating to connect said pair of contacts and cause the application of a triggering signal to the control electrode of said thyristor via said third terminal.
References Cited (Backward Citations)
US3207875A
Cited
US3501677A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-08-16 | 1975-02-15 | 1975-08-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-08-16 | 1979-02-15 | 1979-08-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-08-16 | 1983-02-15 | 1983-08-17 | $7700.00 | Window Closed / Lapsed |