US3793580A
Expired / Lapsed
US
⏱️ 0.0 years remaining
D. c. static switch circuit with a main switch device and a power sharing circuit portion
Assignee: Westinghouse Electric Corp
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Filing: 1972-05-23
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Granted: 1974-02-19
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Expires: 1992-05-23
Abstract
Abstract In a static switch circuit with a power sharing circuit portion operable to dissipate power so the required dissipation is shared with the main power switch in the circuit, the power sharing circuit portion has an NPN transistor and a PNP transistor connected in a white circuit configuration that is provided with bias signals from the center tap of the primary winding of the transformer used in the oscillator of the driver circuit for the main power switch.
Inventors
- 👤 D Baker
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 21:29
CPC Classifications
G; G05; G05F; G05F1/00; G05F1/10; G05F1/46; G05F1/56; G05F1/565; G05F1/569; G05F1/573; H; H02; H02H; H02H7/00; H02H7/10; H02H7/12; H02H9/00; H02H9/02
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
153 words
Apparatus to control the application of DC power from a supply to a load comprising: a first static switching device having first and second electrodes for connection in a first circuit branch between a direct voltage source and a load to be supplied by the source and also having a third control electrode; a power sharing circuit portion connected in parallel with said first and second electrodes of said device, said power sharing circuit portion comprising a transistor having emitter, collector and base electrodes; a driver circuit portion connected to said third electrode of said device; said driver circuit portion comprising a drive oscillator with a transformer having a primary winding with a center tap and having a secondary winding; and means to drivE said power sharing circuit portion comprising a line connected from said center tap of said primary winding to the base of said transistor of said power sharing circuit portion.
Claim 2
Dependent Claim
153 words
Apparatus to control the application of DC power from a supply to a load comprising: a first static switching device having first and second electrodes for connection in a first circuit branch between a direct voltage source and a load to be supplied by the source and also having a third control electrode; a power sharing circuit portion connected in parallel with said first and second electrodes of said device, said power sharing circuit portion comprising a transistor having emitter, collector and base electrodes; a driver circuit portion connected to said third electrode of said device; said driver circuit portion comprising a drive oscillator with a transformer having a primary winding with a center tap and having a secondary winding; and means to drivE said power sharing circuit portion comprising a line connected from said center tap of said primary winding to the base of said transistor of said power sharing circuit portion.
Claim 3
Dependent Claim
51 words
The subject matter of claim 1 wherein: said power sharing circuit comprises a PNP transistor and an NPN transistor, the emitter of PNP transistor and the collector of said NPN transistor being connected together and the collector of said PNP transistor and the base of said NPN transistor being connected together.
Claim 4
Dependent Claim
56 words
The subject matter of claim 9 wherein: the common connection of the emitter of said PNP transistor and the collector of the NPN transistor is resistively connected to a first point for connection to a DC supply, and the emitter of said NPN transistor is resistively connected to a second point for connection to a load.
Claim 5
Dependent Claim
34 words
The subject matter of claim 3 further comprising: a resistance connected across the emitter and base of said PNP transistor and an additional resistance connected across the emitter and base of said NPN transistor.
Claim 6
Dependent Claim
39 words
The subject matter of claim 3 wherein: said power sharing circuit portion further comprises means connected between said first point and the input of said PNP transistor for controlling the current limiting level of the power sharing circuit portion.
Claim 7
Dependent Claim
48 words
The subject matter of claim 5 wherein: said means for controlling the current limiting level of the power sharing circuit portion comprises a diode rectifier poled in the forward direction for current from the source and a Zener diode serially connected in reverse polarity with said diode rectifier.
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) | 1977-02-18 | 1977-08-20 | 1978-02-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-02-18 | 1981-08-20 | 1982-02-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-02-18 | 1985-08-20 | 1986-02-19 | $7700.00 | Window Closed / Lapsed |