Patent US3421157A successfully refreshed from Google Patents.
US3421157A
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Lamp outage detector
Assignee: Cooper Industries LLC
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Filing: 1966-01-24
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Granted: 1969-01-07
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Expires: 1986-01-24
Abstract
No abstract record available.
Inventors
- 👤 Carl E Atkins
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 12:36
CPC Classifications
B; B60; B60Q; B60Q11/00; B60Q11/005
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
180 words
A LAMP OUTAGE DETECTOR FOR PROVIDING A SIGNAL WHEN ANY ONE OF A GROUP OF LAMPS NOT PASS CURRENT WHEN ELECTRICAL POWER IS APPLIED COMPRISING; A FIRST GROUP OF LAMPS; A SECOND GROUP OF LAMPS; A SOURCE OF DIRECT CURRENT POWER CONNECTED TO SAID GROUPS BY RESPECTIVE SWITCHES; A FIRST SAMPLING RESISTOR CONNECTED IN SERIES WITH THE SOURCE OF POWER AND THE FIRST GROUP OF LAMPS; A SECOND SAMPLING RESISTOR CONNECTED IN SERIES WITH THE SOURCE OF POWER AND THE SECOND GROUP OF LAMPS; A SEMICONDUCTOR DIODE COUPLED TO EACH SAMPLING RESISTOR BY A COUPLING CIRCUIT WHICH APPLIES A REVERSE BIAS TO THE DIODE; AN ALTERNATING CURRENT OSCILLATOR CONNECTED TO EACH OF SAID DIODES FOR APPLYING NEGATIVE PULSES THERETO, SAID PULSES NORMALLY HAVING AMPLITUDES WHICH ARE LESS THAN THE REVERSE BIAS ON THE DIODE; A LATCH CIRCUIT COUPED TO SAID DIODES FOR ACTUATION WHEN A LAMP IN ANY ONE OF SAID GROUPS FAILS TO PASS CURRENT WHEN ITS SWITCH IS CLOSED; AND IN INDICATOR MEANS CONNECTED TO SAID LATCH CIRCUIT FOR GIVING AN INDICATION WHEN SAID LATCH CIRCUIT IS OPERATED.
Claim 2
Dependent Claim
180 words
A LAMP OUTAGE DETECTOR FOR PROVIDING A SIGNAL WHEN ANY ONE OF A GROUP OF LAMPS NOT PASS CURRENT WHEN ELECTRICAL POWER IS APPLIED COMPRISING; A FIRST GROUP OF LAMPS; A SECOND GROUP OF LAMPS; A SOURCE OF DIRECT CURRENT POWER CONNECTED TO SAID GROUPS BY RESPECTIVE SWITCHES; A FIRST SAMPLING RESISTOR CONNECTED IN SERIES WITH THE SOURCE OF POWER AND THE FIRST GROUP OF LAMPS; A SECOND SAMPLING RESISTOR CONNECTED IN SERIES WITH THE SOURCE OF POWER AND THE SECOND GROUP OF LAMPS; A SEMICONDUCTOR DIODE COUPLED TO EACH SAMPLING RESISTOR BY A COUPLING CIRCUIT WHICH APPLIES A REVERSE BIAS TO THE DIODE; AN ALTERNATING CURRENT OSCILLATOR CONNECTED TO EACH OF SAID DIODES FOR APPLYING NEGATIVE PULSES THERETO, SAID PULSES NORMALLY HAVING AMPLITUDES WHICH ARE LESS THAN THE REVERSE BIAS ON THE DIODE; A LATCH CIRCUIT COUPED TO SAID DIODES FOR ACTUATION WHEN A LAMP IN ANY ONE OF SAID GROUPS FAILS TO PASS CURRENT WHEN ITS SWITCH IS CLOSED; AND IN INDICATOR MEANS CONNECTED TO SAID LATCH CIRCUIT FOR GIVING AN INDICATION WHEN SAID LATCH CIRCUIT IS OPERATED.
References Cited (Backward Citations)
US3143729A
Cited
US3252157A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1972-01-07 | 1972-07-08 | 1973-01-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1976-01-07 | 1976-07-08 | 1977-01-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1980-01-07 | 1980-07-08 | 1981-01-07 | $7700.00 | Window Closed / Lapsed |