US3633095A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Zero-crossing power line control system
Assignee: Fairchild Semiconductor Corp
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Filing: 1970-07-31
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Granted: 1972-01-04
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Expires: 1990-07-31
Abstract
Abstract A zero-crossing control system operative responsive to zero crossing of power line voltage or current. Each input signal results in the application of one full (360*) cycle of power to the load, the control circuit operating on each input signal to deliver a gate pulse to the power line switch at each of the next two zero line crossings. A hysteresis transfer characteristic is provided in the input circuit of the control system including time proportioning circuits which may be utilized in the control system and output-pulse-forming circuits, circuits providing delay turn-on of the power switch and delay of the input signal, and open and shorted input sensor detector circuits and, operation of the control system with three-phase systems.
Inventors
- 👤 Robert B Hood
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 19:17
CPC Classifications
G; G05; G05F; G05F1/00; G05F1/10; G05F1/12; G05F1/40; G05F1/44; G05F1/45; G05F1/452; G05D; G05D23/00; G05D23/19; G05D23/1906; G05D23/1913; G05D23/20; G05D23/24; H; H03; H03K; H03K17/00; H03K17/13; H03K17/136
Claims Analysis
Total Claims: 30
Claim 1
Independent Claim
199 words
A control circuit for operating a gate-controlled power switch serving to connect a load circuit with an AC power supply line, said control circuit being operable in response to an input signal, said control circuit comprising first circuit means including a pulse generator responsive to said input signal for delivering pulses of energy to the gate of said power switch to activate said switch and couple the load circuit to the power supply line, and second circuit means coupled to said power switch and responsive to the line current signal at said power switch crossing zero for operating said pulse generator means to deliver said pulses of energy to said power switch at said zero crossing, said pulse generator comprising a capacitor having electrical energy stored therein in response to said input signal and switch means operable by said second circuit means for delivering successive portions of said stored energy to said gate at successive zero-crossing points, said switch means comprising a pair of switch circuits coupled to said energy storage means and to said second circuit means, said switch circuits being operated in sequence by said second circuit means to deliver said successive energy portions to said gate.
Claim 2
Dependent Claim
199 words
A control circuit for operating a gate-controlled power switch serving to connect a load circuit with an AC power supply line, said control circuit being operable in response to an input signal, said control circuit comprising first circuit means including a pulse generator responsive to said input signal for delivering pulses of energy to the gate of said power switch to activate said switch and couple the load circuit to the power supply line, and second circuit means coupled to said power switch and responsive to the line current signal at said power switch crossing zero for operating said pulse generator means to deliver said pulses of energy to said power switch at said zero crossing, said pulse generator comprising a capacitor having electrical energy stored therein in response to said input signal and switch means operable by said second circuit means for delivering successive portions of said stored energy to said gate at successive zero-crossing points, said switch means comprising a pair of switch circuits coupled to said energy storage means and to said second circuit means, said switch circuits being operated in sequence by said second circuit means to deliver said successive energy portions to said gate.
Claim 3
Dependent Claim
90 words
A control circuit as claimed in claim 1 wherein said second circuit means comprises a resistor coupled to one terminal of said power switch and a pair of transistor circuits, one transistor circuit being operative at the start of one half-cycle of the line current at said power switch to activate one of said switch means in said pulse generator and the other transistor circuit being operative at the start of the other half-cycle of the line current to activate the second of said switch means in said pulse generator.
Claim 4
Dependent Claim
41 words
A control circuit as claimed in claim 1 including means coupled to a first one of said pair of switch circuits for limiting the energy delivered by said one switch circuit from said energy storage means to said power switch gate.
Claim 5
Dependent Claim
49 words
A control circuit as claimed in claim 1 wherein said pair of switch circuits include a common transistor circuit coupled to said energy storage means, each of said switch circuits, when activated, operating said common transistor circuit to deliver the energy from said energy storage means to said gate.
Claim 6
Dependent Claim
43 words
A control circuit as claimed in claim 1 wherein said first circuit means comprises an amplifier circuit responsive to said input signal and a switch circuit coupled to said amplifier and operated therefrom to couple said energy storage means to an energy source.
Claim 7
Dependent Claim
16 words
A control circuit as claimed in claim 5 wherein said energy storage means comprises a capacitor.
Claim 8
Dependent Claim
26 words
A control circuit as claimed in claim 5 wherein said amplifier means comprises a differential amplifier circuit including two branch circuits and a common current source.
Claim 9
Dependent Claim
31 words
A control circuit as claimed in claim 7 wherein said switch circuit is coupled to one of said branch circuits and is responsive to the current flow through said branch circuit.
Claim 10
Dependent Claim
43 words
A control circuit as claimed in claim 5 including circuit means coupled to said power line and to said amplifier circuit and operative during one of two half-cycles in each full cycle of power on said power line to energize said amplifier circuit.
Claim 11
Dependent Claim
34 words
A control circuit as claimed in claiM 9 including a memory circuit coupled to said amplifier for maintaining a record of the condition of said amplifier from one positive line cycle to the next.
Claim 12
Dependent Claim
90 words
A control circuit as claimed in claim 5 and having an input hysteresis transfer characteristic, wherein said amplifier circuit is activated responsive to a particular voltage level of input including an input circuit for producing said voltage level input to said amplifier and responsive to a variable level external control signal, and means in said input circuit responsive to the activation of said amplifier circuit for varying the level at which said input circuit is responsive to said external control signal to produce said voltage level input to said amplifier.
Claim 13
Dependent Claim
45 words
A control circuit as claimed in claim 11 wherein said input circuit comprises a bridge circuit for receiving said external control signal, and wherein said means responsive to said amplifier activation comprises a circuit component in one arm of said bridge coupled to said amplifier.
Claim 14
Dependent Claim
38 words
A control circuit as claimed in claim 11 including circuit means coupled to said power line and to said amplifier circuit and operative during the positive half-cycles of power on said power line to energize said amplifier circuit.
Claim 15
Dependent Claim
34 words
A control circuit as claimed in claim 13 including a memory circuit coupled to said amplifier for maintaining a record of the condition of said amplifier from one positive line cycle to the next.
Claim 16
Dependent Claim
75 words
A control circuit as claimed in claim 1 comprising a second pulse generator including a second energy storage means therein, and circuit means for coupling said second pulse generator between said first pulse generator and said gate, said second pulse generator operating in response to the portions of energy delivered thereto from said first pulse generator for generating energy pulses from the energy storage means in said second pulse generator for delivery to said gate.
Claim 17
Dependent Claim
11 words
Claim 15 wherein said second energy storage means comprises a capacitor.
Claim 18
Dependent Claim
43 words
A control circuit as claimed in claim 1 wherein said second circuit means comprises a delay circuit for delaying the response to a first line current zero crossing, and means for disabling said delay circuit from operating during subsequent line signal zero crossings.
Claim 19
Dependent Claim
90 words
A control circuit as claimed in claim 1 wherein said second circuit means comprises a resistor coupled to one terminal of said power switch and a pair of transistor circuits, one transistor circuit being operative at the start of one half-cycle of the line signal to activate said pulse generator to deliver one pulse to said power switch and the other transistor circuit being operative at the start of the next half-cycle of the line signal to activate said pulse generator to deliver a second pulse to said power switch.
Claim 20
Dependent Claim
60 words
A control circuit as claimed in claim 18 wherein said pulse generator comprises energy storage means having electrical energy stored therein in response to said input signal, said pulse generator being operable by said second circuit means for delivering successive portions of said stored energy as said first and second pulses to said power switch at successive zero crossing points.
Claim 21
Dependent Claim
16 words
A control circuit as claimed in claim 19 wherein said energy storage means comprises a capacitor.
Claim 22
Dependent Claim
51 words
A control circuit as claimed in claim 19 wherein said pulse generator comprises a pair of switch circuits coupled to said energy storage means and to said second circuit means, said switch circuits being operated in sequence by said second means to deliver said successive energy portions to said power switch.
Claim 23
Dependent Claim
43 words
A control circuit as claimed in claim 19 wherein said first circuit means comprises an amplifier circuit responsive to said input signal and a switch circuit coupled to said amplifier and operated therefrom to couple said energy storage means to an energy source.
Claim 24
Dependent Claim
26 words
A control circuit as claimed in claim 22 wherein said amplifier means comprises a differential amplifier circuit including two branch circuits and a common current source.
Claim 25
Dependent Claim
32 words
A control circuit as claimed in claim 23 wherein said switch circuit is coupled to one of said branch circuits and is responsive to the current flow through said one branch circuit.
Claim 26
Dependent Claim
69 words
A control circuit as claimed in claim 1 wherein said first circuit means comprises an amplifier circuit responsive to said input signal for delivering energy to said pulse generator and circuit means coupled to said power line and to said amplifier circuit and operative during one of the two half-cycles in each full cycle of power on said power line to energize said amplifier circuit during said one half-cycle.
Claim 27
Dependent Claim
137 words
A control system having an input hysteresis transfer characteristic comprising: an amplifier circuit activated responsive to a particular voltage level of input; an input circuit for producing said voltage level input to said amplifier and responsive to a variable level external control signal; means in said input circuit responsive to the activation of said amplifier circuit for varying the level at which said input circuit is responsive to said external control signal to produce said voltage level input to said amplifier; and circuit means coupled to a power line and to said amplifier circuit and operative during the positive half-cycles of power on said power line to energize said amplifier circuit; and a memory circuit coupled to said amplifier for maintaining a record of the condition of said amplifier from one positive line cycle to the next.
Claim 28
Dependent Claim
137 words
A control system having an input hysteresis transfer characteristic comprising: an amplifier circuit activated responsive to a particular voltage level of input; an input circuit for producing said voltage level input to said amplifier and responsive to a variable level external control signal; means in said input circuit responsive to the activation of said amplifier circuit for varying the level at which said input circuit is responsive to said external control signal to produce said voltage level input to said amplifier; and circuit means coupled to a power line and to said amplifier circuit and operative during the positive half-cycles of power on said power line to energize said amplifier circuit; and a memory circuit coupled to said amplifier for maintaining a record of the condition of said amplifier from one positive line cycle to the next.
Claim 29
Dependent Claim
45 words
A control system as claimed in claim 26 wherein said input circuit comprises a bridge circuit for receiving said external control signal, and wherein said means responsive to said amplifier activation comprises a circuit component in one arm of said bridge coupled to said amplifier.
Claim 30
Dependent Claim
51 words
A control system as claimed in claim 26 including a sawtooth generator for producing a sawtooth waveform, each sawtooth wave extending over a plurality of power line cycles, and circuit means in said input circuit responsive to said sawtooth wave for varying the voltage level at which said amplifier is activated.
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) | 1975-01-03 | 1975-07-05 | 1976-01-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-01-03 | 1979-07-05 | 1980-01-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-01-03 | 1983-07-05 | 1984-01-04 | $7700.00 | Window Closed / Lapsed |