Patent US3710231A successfully refreshed from Google Patents.
US3710231A
Expired / Lapsed
US
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D.c. static switch including means to suppress transient spikes between a drive source and the switch element
Assignee: Westinghouse Electric Corp
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Filing: 1971-03-15
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Granted: 1973-01-09
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Expires: 1991-03-15
Abstract
Abstract A low voltage drop, D.C. static switch with improved controllability for current limiting is provided wherein the transient spikes from a drive source such as a free running, core-timed oscillator are suppressed by one or more static amplifier stages before the drive signal is supplied to the power switch element. A current limit controller can be isolated from the transient spike source. Such switches have good characteristics for remote power controllers.
Inventors
- 👤 D Baker
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 14:17
CPC Classifications
H; H02; H02M; H02M3/00; H02M3/02; H02M3/04; H02M3/10; H02M3/145; H02M3/155; H02M3/156
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
225 words
Apparatus to control the application of D.C. power from a supply circuit point to a load circuit point, comprising: a first static switching and amplifying device having first, second and third electrodes of which said first electrode is connected to the supply circuit point and said third electrode is connected to the load circuit point, said second electrode being a control electrode, a transformer having a saturable core and at least one winding thereon having a plurality of turns, a first number of turns disposed symmetrically about a center tap on said at least one winding connected at symmetrical taps respectively through like poled diode rectifiers to a common line, said center tap being connected to said supply circuit point; at least one additional static switching and amplifying device in at least one amplification stage having an input from said common line, an output to said second electrode of said first static switching and amplifying device, said second electrode being isolated from said common line by said at least one amplification stage, and said at least one amplification stage also having a control point connected to current limit control means for permitting variable control of the amount of signal applied to said second electrode of said first static switching and amplifying device without any appreciable spikes in the current applied to said load circuit point.
Claim 2
Dependent Claim
225 words
Apparatus to control the application of D.C. power from a supply circuit point to a load circuit point, comprising: a first static switching and amplifying device having first, second and third electrodes of which said first electrode is connected to the supply circuit point and said third electrode is connected to the load circuit point, said second electrode being a control electrode, a transformer having a saturable core and at least one winding thereon having a plurality of turns, a first number of turns disposed symmetrically about a center tap on said at least one winding connected at symmetrical taps respectively through like poled diode rectifiers to a common line, said center tap being connected to said supply circuit point; at least one additional static switching and amplifying device in at least one amplification stage having an input from said common line, an output to said second electrode of said first static switching and amplifying device, said second electrode being isolated from said common line by said at least one amplification stage, and said at least one amplification stage also having a control point connected to current limit control means for permitting variable control of the amount of signal applied to said second electrode of said first static switching and amplifying device without any appreciable spikes in the current applied to said load circuit point.
Claim 3
Dependent Claim
51 words
The subject matter of claim 1 wherein: said static switching and amplifying devices are transistors, said second electrode of said first device being the base electrode thereof; and further comprising a free running, core-timed oscillator including said transformer for developing signals to said turns connected to said like poled diode rectifiers.
Claim 4
Dependent Claim
35 words
The subject matter of claim 2 wherein said current limit control means is electrically isolated from said at least one winding of said transformer and is not influenced by transient spikes developed in said transformer.
Claim 5
Dependent Claim
130 words
In an electrical power system, the combination comprising: a power transistor with a collectOr-emitter path connected between a source of direct voltage and a load, a transistor amplifier circuit connected to the base of said power transistor; means including a free running, core-timed oscillator for developing signals applied to the input of said transistor amplifier circuit; current limit control means also connected to the input of said amplifier to permit modification of current supplied to the base of said power transistor; said free running, core-timed oscillator including a transformer exhibiting characteristic leakage inductance evidenced as voltage spikes on its windings upon going in and out of saturation; said current limit control means and the base of said power transistor being effectively isolated from said voltage spikes by said amplifier circuit.
Claim 6
Dependent Claim
130 words
In an electrical power system, the combination comprising: a power transistor with a collectOr-emitter path connected between a source of direct voltage and a load, a transistor amplifier circuit connected to the base of said power transistor; means including a free running, core-timed oscillator for developing signals applied to the input of said transistor amplifier circuit; current limit control means also connected to the input of said amplifier to permit modification of current supplied to the base of said power transistor; said free running, core-timed oscillator including a transformer exhibiting characteristic leakage inductance evidenced as voltage spikes on its windings upon going in and out of saturation; said current limit control means and the base of said power transistor being effectively isolated from said voltage spikes by said amplifier circuit.
Claim 7
Dependent Claim
118 words
Apparatus to control the application of D.C. power from a supply circuit point to a load circuit point, comprising: static switching means having first and second electrodes between supply and load circuit points and a control electrode; means to develop a D.C. drive signal characterized by appreciable transient current spikes; and means to suppress said transient current spikes connected intermediate said D.C. drive signal means and said control electrode,said means to suppress said transient current spikes comprising at least one static amplifier stage and current limit control means to control the magnitude of drive current to said at least one static amplifier stage in accordance with variations in magnitude of current between said supply and load circuit points.
Claim 8
Dependent Claim
118 words
Apparatus to control the application of D.C. power from a supply circuit point to a load circuit point, comprising: static switching means having first and second electrodes between supply and load circuit points and a control electrode; means to develop a D.C. drive signal characterized by appreciable transient current spikes; and means to suppress said transient current spikes connected intermediate said D.C. drive signal means and said control electrode,said means to suppress said transient current spikes comprising at least one static amplifier stage and current limit control means to control the magnitude of drive current to said at least one static amplifier stage in accordance with variations in magnitude of current between said supply and load circuit points.
Claim 9
Dependent Claim
43 words
The subject matter of claim 5 wherein: said means to develop a D.C. drive signal characterized by appreciable transient current spikes comprises a free-running core time oscillator; and said static switching means and said at least one static amplifier each comprise a transistor.
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) | 1976-01-09 | 1976-07-10 | 1977-01-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-01-09 | 1980-07-10 | 1981-01-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-01-09 | 1984-07-10 | 1985-01-09 | $7700.00 | Window Closed / Lapsed |