Patent US3617856A successfully refreshed from Google Patents.
US3617856A
Expired / Lapsed
US
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Alternator under-frequency detecting circuit
Assignee: Motors Liquidation Co
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Filing: 1970-11-18
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Granted: 1971-11-02
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Expires: 1990-11-18
Abstract
Abstract An alternator under-frequency detecting circuit for reducing the alternator output potential with conditions of less than normal output potential frequency. A source of each an alternating current sensing potential and an alternating current auxiliary sensing potential are connected in series aiding relationship across the alternating current input circuitry of a sensing potential rectifier circuit and a pair of silicon-controlled rectifiers are connected in an opposite polarity relationship across the source of alternating current auxiliary sensing potential. A trigger signal, produced at the beginning of each selected half-cycle of the alternating current auxiliary sensing potential for a predetermined duration of time greater than the normal frequency period of the selected half-cycles is applied across the gate-cathode electrodes of one of the siliconcontrolled rectifiers. With normal alternator output potential frequency, the silicon-controlled rectifiers are triggered conductive to effectively shunt the auxiliary sensing potential from the rectifier circuit and the alternator-rectifier system functions normally. With less than normal alternator output potential frequency, the silicon-controlled rectifiers are not triggered conductive, consequently, the sensing and auxiliary sensing potentials are applied across the rectifier circuit in a series aiding relationship, are rectified thereby and sensed by a potential regulator circuit which decreases the alternator field excitation and output potential magnitude.
Inventors
- 👤 Richard N Lehnhoff
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 03:36
CPC Classifications
H; H02; H02P; H02P9/00; H02P9/14; H02P9/26; H02P9/30
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
291 words
An alternator underfrequency detecting circuit for reducing the alternator output potential with conditions of less than normal output potential frequency comprising in combination with an alternator, a sensing potential rectifier circuit having alternating current input circuitry and direct current output circuitry and a potential regulator circuit connected across the rectifier circuit output circuitry, a source of each an alternating current sensing potential and an alternating current auxiliary sensing potential, each of a frequency the same as the frequency of the output potential of said alternator, means for connecting said source of alternating current sensing potential and said source of alternating current auxiliary sensing potential in series aiding relationship across said sensing potential rectifier circuit alternating current input circuitry, first and second silicon-controlled rectifiers each having anode, cathode and gate electrodes, means for connecting said anodecathode electrodes of said silicon-controlled rectifiers in an opposite polarity relationship across said source of alternating current auxiliary sensing potential, means for producing a trigger signal at the beginning of each selected half-cycle of said alternating current auxiliary sensing potential for a predetermined duration of time greater than the normal frequency period of said selected half-cycles, means for applying said trigger signal across said gate-cathode electrodes of the one said silicon-controlled rectifier which is reverse poled by said auxiliary sensing potential during said selected half-cycles thereof, means for applying said auxiliary sensing potential across said gate cathode electrodes of the other said siliconcontrolled rectifier during each other half-cycle of said auxiliary sensing potential while said the one said siliconcontrolled rectifier is conducting, and means for triggering said other said silicon-controlled rectifier conductive during each selected half-cycle of said auxiliary sensing potential only after said the one said silicon-controlled rectifier has conducted during the preceding other said half-cycle.
Claim 2
Dependent Claim
291 words
An alternator underfrequency detecting circuit for reducing the alternator output potential with conditions of less than normal output potential frequency comprising in combination with an alternator, a sensing potential rectifier circuit having alternating current input circuitry and direct current output circuitry and a potential regulator circuit connected across the rectifier circuit output circuitry, a source of each an alternating current sensing potential and an alternating current auxiliary sensing potential, each of a frequency the same as the frequency of the output potential of said alternator, means for connecting said source of alternating current sensing potential and said source of alternating current auxiliary sensing potential in series aiding relationship across said sensing potential rectifier circuit alternating current input circuitry, first and second silicon-controlled rectifiers each having anode, cathode and gate electrodes, means for connecting said anodecathode electrodes of said silicon-controlled rectifiers in an opposite polarity relationship across said source of alternating current auxiliary sensing potential, means for producing a trigger signal at the beginning of each selected half-cycle of said alternating current auxiliary sensing potential for a predetermined duration of time greater than the normal frequency period of said selected half-cycles, means for applying said trigger signal across said gate-cathode electrodes of the one said silicon-controlled rectifier which is reverse poled by said auxiliary sensing potential during said selected half-cycles thereof, means for applying said auxiliary sensing potential across said gate cathode electrodes of the other said siliconcontrolled rectifier during each other half-cycle of said auxiliary sensing potential while said the one said siliconcontrolled rectifier is conducting, and means for triggering said other said silicon-controlled rectifier conductive during each selected half-cycle of said auxiliary sensing potential only after said the one said silicon-controlled rectifier has conducted during the preceding other said half-cycle.
Claim 3
Dependent Claim
294 words
An alternator underfrequency detecting circuit for reducing the alternator output potential with conditions of less than normal output potential frequency comprising in combination with an alternator, a sensing potential rectifier circuit having alternating current input circuitry and direct current output circuitry and a potential regulator circuit connected across the rectifier output circuitry, a source of each an alternating current sensing potential and an alternating current auxiliary sensing potential, each of a frequency the same as the frequency of the output potential of said alternator, an impedance, means including said impedance for connecting said source of alternating current sensing potential and said source of alternating current auxiliary sensing potential in series aiding relationship across said sensing potential rectifier circuit alternating current input circuitry, first and second silicon-controlled rectifiers each having anode, cathode and gate electrodes, means for connecting said anode-cathode electrodes of said silicon-controlled rectifiers in an opposite polarity relationship across said source of alternating current auxiliary sensing potential, means for producing a trigger signal at the begInning of each selected half-cycle of said alternating current auxiliary sensing potential for a predetermined duration of time greater than the normal frequency period of said selected half-cycles, means for applying said trigger signal across said gate-cathode electrodes of the one said silicon-controlled rectifier which is reverse poled by said auxiliary sensing potential during said selected half-cycles thereof, means for applying said auxiliary sensing potential across said gate-cathode electrodes of the other said silicon-controlled rectifier during each other half-cycle of said auxiliary sensing potential while said the one said silicon-controlled rectifier is conducting, and means for triggering said other said silicon-controlled rectifier conductive during each selected half-cycle of said auxiliary sensing potential only after said the one said silicon-controlled rectifier has conducted during the preceding other said half-cycle.
Claim 4
Dependent Claim
294 words
An alternator underfrequency detecting circuit for reducing the alternator output potential with conditions of less than normal output potential frequency comprising in combination with an alternator, a sensing potential rectifier circuit having alternating current input circuitry and direct current output circuitry and a potential regulator circuit connected across the rectifier output circuitry, a source of each an alternating current sensing potential and an alternating current auxiliary sensing potential, each of a frequency the same as the frequency of the output potential of said alternator, an impedance, means including said impedance for connecting said source of alternating current sensing potential and said source of alternating current auxiliary sensing potential in series aiding relationship across said sensing potential rectifier circuit alternating current input circuitry, first and second silicon-controlled rectifiers each having anode, cathode and gate electrodes, means for connecting said anode-cathode electrodes of said silicon-controlled rectifiers in an opposite polarity relationship across said source of alternating current auxiliary sensing potential, means for producing a trigger signal at the begInning of each selected half-cycle of said alternating current auxiliary sensing potential for a predetermined duration of time greater than the normal frequency period of said selected half-cycles, means for applying said trigger signal across said gate-cathode electrodes of the one said silicon-controlled rectifier which is reverse poled by said auxiliary sensing potential during said selected half-cycles thereof, means for applying said auxiliary sensing potential across said gate-cathode electrodes of the other said silicon-controlled rectifier during each other half-cycle of said auxiliary sensing potential while said the one said silicon-controlled rectifier is conducting, and means for triggering said other said silicon-controlled rectifier conductive during each selected half-cycle of said auxiliary sensing potential only after said the one said silicon-controlled rectifier has conducted during the preceding other said half-cycle.
Claim 5
Dependent Claim
301 words
An alternator underfrequency detecting circuit for reducing the alternator output potential with conditions of less than normal output potential frequency comprising in combination with an alternator, a sensing potential rectifier circuit having alternating current input circuitry and direct current output circuitry and a potential regulator circuit connected across the rectifier output circuitry, a source of each an alternating current sensing potential and an alternating current auxiliary sensing potential, each of a frequency the same as the frequency of the output potential of said alternator, an impedance, means including said impedance for connecting said source of alternating current sensing potential and said source of alternating current auxiliary sensing potential in series aiding relationship across said sensing potential rectifier circuit alternating current input circuitry, first and second silicon-controlled rectifiers each having anode, cathode and gate electrodes, means for connecting said anode-cathode electrodes of said silicon-controlled rectifiers in an opposite polarity relationship across said source of alternating current auxiliary sensing potential, a monostable multivibrator circuit responsive to selected half-cycles of said auxiliary sensing potential, for producing a trigger signal at the beginning of each said selected half-cycle thereof for a predetermined duration of time greater than the normal frequency period of said selected half-cycles, means for applying said trigger signal across said gate-cathode electrodes of the one said silicon-controlled rectifier which is reverse poled by said auxiliary sensing potential during said selected half-cycles thereof, means for applying said auxiliary sensing potential across said gate-cathode electrodes of the other said silicon-controlled rectifier during each other half-cycle of said auxiliary sensing potential while said the one said silicon-controlled rectifier is conducting, and means for triggering said other said silicon-controlled rectifier conductive during each selected half-cycle of said auxiliary sensing potential only after said the one said silicon-controlled rectifier has conducted during the preceding other said half-cycle.
Claim 6
Dependent Claim
301 words
An alternator underfrequency detecting circuit for reducing the alternator output potential with conditions of less than normal output potential frequency comprising in combination with an alternator, a sensing potential rectifier circuit having alternating current input circuitry and direct current output circuitry and a potential regulator circuit connected across the rectifier output circuitry, a source of each an alternating current sensing potential and an alternating current auxiliary sensing potential, each of a frequency the same as the frequency of the output potential of said alternator, an impedance, means including said impedance for connecting said source of alternating current sensing potential and said source of alternating current auxiliary sensing potential in series aiding relationship across said sensing potential rectifier circuit alternating current input circuitry, first and second silicon-controlled rectifiers each having anode, cathode and gate electrodes, means for connecting said anode-cathode electrodes of said silicon-controlled rectifiers in an opposite polarity relationship across said source of alternating current auxiliary sensing potential, a monostable multivibrator circuit responsive to selected half-cycles of said auxiliary sensing potential, for producing a trigger signal at the beginning of each said selected half-cycle thereof for a predetermined duration of time greater than the normal frequency period of said selected half-cycles, means for applying said trigger signal across said gate-cathode electrodes of the one said silicon-controlled rectifier which is reverse poled by said auxiliary sensing potential during said selected half-cycles thereof, means for applying said auxiliary sensing potential across said gate-cathode electrodes of the other said silicon-controlled rectifier during each other half-cycle of said auxiliary sensing potential while said the one said silicon-controlled rectifier is conducting, and means for triggering said other said silicon-controlled rectifier conductive during each selected half-cycle of said auxiliary sensing potential only after said the one said silicon-controlled rectifier has conducted during the preceding other said half-cycle.
Claim 7
Dependent Claim
276 words
An alternator underfrequency detecting circuit for reducing the alternator output potential with conditions of less than normal output potential frequency comprising in combination with an alternator, a sensing potential rectifier circuit having alternating current input circuitry and direct current output circuitry and a potential regulator circuit connected across said rectifier output circuitry, a source of each an alternating current sensing potential and an alternating current auxiliary sensing potential, each of a frequency the same as the frequency of the output potential of said alternator, an impedance, means including said impedance for connecting said source of alternating current sensing potential and said source of alternating current auxiliary sensing potential in series aiding relationship across said sensing potenTial rectifier circuit alternating current input circuitry, first and second silicon-controlled rectifiers each having anode, cathode and gate electrodes, means for connecting said anode-cathode electrodes of said silicon-controlled rectifiers in an opposite polarity relationship across said source of alternating current auxiliary sensing potential, a monostable multivibrator circuit responsive to selected half-cycles of said auxiliary sensing potential for producing a trigger signal at the beginning of each said selected half-cycle thereof for a predetermined duration of time greater than the normal frequency period of said selected half-cycles, means for applying said trigger signal across said gate-cathode electrodes of the one said silicon-controlled rectifier which is reverse poled by said auxiliary sensing potential during said selected half-cycles thereof, a diode, a capacitor, means for connecting said diode and said capacitor in series across said source of alternating current auxiliary sensing potential, and means for connecting said gate electrode of the other said silicon-controlled rectifier to the junction between said diode and said capacitor.
Claim 8
Dependent Claim
276 words
An alternator underfrequency detecting circuit for reducing the alternator output potential with conditions of less than normal output potential frequency comprising in combination with an alternator, a sensing potential rectifier circuit having alternating current input circuitry and direct current output circuitry and a potential regulator circuit connected across said rectifier output circuitry, a source of each an alternating current sensing potential and an alternating current auxiliary sensing potential, each of a frequency the same as the frequency of the output potential of said alternator, an impedance, means including said impedance for connecting said source of alternating current sensing potential and said source of alternating current auxiliary sensing potential in series aiding relationship across said sensing potenTial rectifier circuit alternating current input circuitry, first and second silicon-controlled rectifiers each having anode, cathode and gate electrodes, means for connecting said anode-cathode electrodes of said silicon-controlled rectifiers in an opposite polarity relationship across said source of alternating current auxiliary sensing potential, a monostable multivibrator circuit responsive to selected half-cycles of said auxiliary sensing potential for producing a trigger signal at the beginning of each said selected half-cycle thereof for a predetermined duration of time greater than the normal frequency period of said selected half-cycles, means for applying said trigger signal across said gate-cathode electrodes of the one said silicon-controlled rectifier which is reverse poled by said auxiliary sensing potential during said selected half-cycles thereof, a diode, a capacitor, means for connecting said diode and said capacitor in series across said source of alternating current auxiliary sensing potential, and means for connecting said gate electrode of the other said silicon-controlled rectifier to the junction between said diode and said capacitor.
Claim 9
Dependent Claim
283 words
An alternator underfrequency detecting circuit for reducing the alternator output potential with conditions of less than normal output potential frequency comprising in combination with an alternator, a sensing potential rectifier circuit having alternating current input circuitry and direct current output circuitry and a potential regulator circuit connected across said rectifier output circuitry, a source of each an alternating current sensing potential and an alternating current auxiliary sensing potential, each of a frequency the same as the frequency of the output potential of said alternator, an impedance, means including said impedance for connecting said source of alternating current sensing potential and said source of alternating current auxiliary sensing potential in series aiding relationship across said sensing potential rectifier circuit alternating current input circuitry, first and second silicon-controlled rectifiers each having anode, cathode and gate electrodes, means for connecting said anode-cathode electrodes of said silicon-controlled rectifiers in an opposite polarity relationship across said source of alternating current auxiliary sensing potential, a monostable multivibrator circuit responsive to selected half-cycles of said auxiliary sensing potential for producing a trigger signal at the beginning of each said selected half-cycle thereof for a predetermined duration of time greater than the normal frequency period of said selected half-cycles, means for applying said trigger signal across said gate-cathode electrodes of the one said silicon-controlled rectifier which is reverse poled by said auxiliary sensing potential during said selected half-cycles thereof, a diode, a resistor, a capacitor, means for connecting said diode, said resistor and said capacitor in series across said source of alternating current auxiliary sensing potential in that order, and means for connecting said gate electrode of the other said silicon-controlled rectifier to the junction between said resistor and said capacitor.
Claim 10
Dependent Claim
283 words
An alternator underfrequency detecting circuit for reducing the alternator output potential with conditions of less than normal output potential frequency comprising in combination with an alternator, a sensing potential rectifier circuit having alternating current input circuitry and direct current output circuitry and a potential regulator circuit connected across said rectifier output circuitry, a source of each an alternating current sensing potential and an alternating current auxiliary sensing potential, each of a frequency the same as the frequency of the output potential of said alternator, an impedance, means including said impedance for connecting said source of alternating current sensing potential and said source of alternating current auxiliary sensing potential in series aiding relationship across said sensing potential rectifier circuit alternating current input circuitry, first and second silicon-controlled rectifiers each having anode, cathode and gate electrodes, means for connecting said anode-cathode electrodes of said silicon-controlled rectifiers in an opposite polarity relationship across said source of alternating current auxiliary sensing potential, a monostable multivibrator circuit responsive to selected half-cycles of said auxiliary sensing potential for producing a trigger signal at the beginning of each said selected half-cycle thereof for a predetermined duration of time greater than the normal frequency period of said selected half-cycles, means for applying said trigger signal across said gate-cathode electrodes of the one said silicon-controlled rectifier which is reverse poled by said auxiliary sensing potential during said selected half-cycles thereof, a diode, a resistor, a capacitor, means for connecting said diode, said resistor and said capacitor in series across said source of alternating current auxiliary sensing potential in that order, and means for connecting said gate electrode of the other said silicon-controlled rectifier to the junction between said resistor and said capacitor.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-11-01 | 1975-05-03 | 1975-11-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-11-01 | 1979-05-03 | 1979-11-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-11-01 | 1983-05-03 | 1983-11-02 | $7700.00 | Window Closed / Lapsed |