US3590276A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Circuit for producing an electrical pulse which occurs at some fixed phase angle with respect to an alternating current input voltage
Assignee: Westinghouse Electric Corp
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Filing: 1969-04-24
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Granted: 1971-06-29
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Expires: 1989-04-24
Abstract
Abstract Described is apparatus for generating an electrical pulse each time an input alternating current signal passes through a complete 360* cycle, the pulse having a fixed phase angle with respect to the zero crossing starting point of each 360* cycle. This is accomplished by means of a resistance-capacitance network in which the capacitor is connected across the emitter-base junction of a switching transistor. When an alternating current input is applied across the resistance-capacitance network, the capacitor will charge only when the emitter-base junction is reverse biased. When the voltage waveform across the capacitor reaches the zero crossing point, the transistor will fire to produce an output pulse. Since this waveform across the capacitor lags the input alternating current waveform by an amount dependent upon the time constant of the resistance-capacitance network, the pulses produced at the output of the transistor switch will always bear a fixed phase relationship with respect to the alternating current input.
Inventors
- 👤 John D Watson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 13:13
CPC Classifications
H; H03; H03D; H03D3/00; H03D3/26; H03K; H03K5/00; H03K5/153
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
149 words
In apparatus for generating an electrical pulse which occurs at some fixed phase angle with respect to an alternating current input voltage, the combination of a semiconductor switch device having a control electrode and two other electrodes, a source of driving potential connected between said other electrodes of the switch device, a pair of input terminals to which said alternating current input voltage is applied, a resistor and a capacitor connected in series across said input terminals whereby one end of the resistor is connected to one end of the capacitor, noncapacitive means connecting said one end of the capacitor to said control electrode, diode means connecting the other end of the capacitor to a first of said other electrodes of the switch device, and output terminals connected to a second of said other electrodes and said other end of the capacitor respectively and across which said pulse appears.
Claim 2
Dependent Claim
149 words
In apparatus for generating an electrical pulse which occurs at some fixed phase angle with respect to an alternating current input voltage, the combination of a semiconductor switch device having a control electrode and two other electrodes, a source of driving potential connected between said other electrodes of the switch device, a pair of input terminals to which said alternating current input voltage is applied, a resistor and a capacitor connected in series across said input terminals whereby one end of the resistor is connected to one end of the capacitor, noncapacitive means connecting said one end of the capacitor to said control electrode, diode means connecting the other end of the capacitor to a first of said other electrodes of the switch device, and output terminals connected to a second of said other electrodes and said other end of the capacitor respectively and across which said pulse appears.
Claim 3
Dependent Claim
22 words
The combination of claim 1 wherein said switch device is a transistor and said control electrode is the base of the transistor.
Claim 4
Dependent Claim
24 words
The apparatus of claim 2 wherein the other end of said capacitor is connected to the emitter of said transistor through said diode means.
Claim 5
Dependent Claim
35 words
The apparatus of claim 3 wherein said source of driving potential has one terminal connected through a resistor to the collector of said transistor and its other terminal connected to the emitter of said transistor.
Claim 6
Dependent Claim
18 words
The apparatus of claim 2 including a diode connecting said one end of the capacitor to said base.
Claim 7
Dependent Claim
169 words
In apparatus for generating an electrical pulse which occurs at some fixed phase angle with respect to an alternating current input voltage, the combination of an input transformer having a primary winding adapted for connection to said alternating current input voltage, said transformer having a secondary winding provided with end terminals and a grounded terminal therebetween, a semiconductor switch device having a control electrode and two other electrodes, a source of driving potential connected between said other electrodes of the switch device, a resistor and a capacitor connected in series between one end terminal of said secondary windinG and said grounded terminal whereby one end of the resistor is connected to one end of the capacitor, means connecting said one end of the capacitor to said control electrode, diode means connecting the other end of the capacitor to one of said other electrodes of the switch device, and means connecting the other end terminal of said secondary winding to said one of the other electrodes of said switch device.
Claim 8
Dependent Claim
169 words
In apparatus for generating an electrical pulse which occurs at some fixed phase angle with respect to an alternating current input voltage, the combination of an input transformer having a primary winding adapted for connection to said alternating current input voltage, said transformer having a secondary winding provided with end terminals and a grounded terminal therebetween, a semiconductor switch device having a control electrode and two other electrodes, a source of driving potential connected between said other electrodes of the switch device, a resistor and a capacitor connected in series between one end terminal of said secondary windinG and said grounded terminal whereby one end of the resistor is connected to one end of the capacitor, means connecting said one end of the capacitor to said control electrode, diode means connecting the other end of the capacitor to one of said other electrodes of the switch device, and means connecting the other end terminal of said secondary winding to said one of the other electrodes of said switch device.
Claim 9
Dependent Claim
45 words
The apparatus of claim 6 wherein said grounded terminal is connected to a midtap on said secondary winding, and including a unidirectional current device connecting said one end of the capacitor to said control electrode, said diode means comprising a pair of diodes in series.
Claim 10
Dependent Claim
16 words
The apparatus of claim 6 wherein said last-named means includes a diode and resistor in series.
Claim 11
Dependent Claim
16 words
The apparatus of claim 6 including a utilization circuit connected to the collector of said transistor.
Claim 12
Dependent Claim
19 words
The apparatus of claim 6 including a resistor connected between the emitter and base of said transistor switch device.
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) | 1974-06-28 | 1974-12-28 | 1975-06-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-06-28 | 1978-12-28 | 1979-06-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-06-28 | 1982-12-28 | 1983-06-29 | $7700.00 | Window Closed / Lapsed |