US3401274A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fail-safe standard amplitude signal sources
Assignee: Westinghouse Air Brake Co
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Filing: 1965-09-10
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Granted: 1968-09-10
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Expires: 1985-09-10
Abstract
No abstract record available.
Inventors
- 👤 Donald B Marsh
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 17:19
CPC Classifications
H; H03; H03G; H03G11/00; H03K; H03K19/00; H03K19/007; H03L; H03L5/00
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
203 words
A FAIL-SAFE STANDARD AMPLITUDE SIGNAL SOURCE COMPRISING: A SOURCE OF SUPPLY POTENTIAL HAVING A PAIR OF TERMINALS, A MULTIVIBRATOR HAVING A FIRST AND A SECOND TRANSISTOR EACH HAVING AN EMITTER, A COLLECTOR AND A BASE ELECTRODE, CAPACITOR MEANS CROSS-COUPLING THE COLLECTOR ELECTRODE OF EACH OF SAID TRANSISTOR TO THE BASE ELECTRODE OF THE OTHER OF SAID TRANSISTORS, A VOLTAGE REGULATOR INCLUDING A ZENER TYPE DIODE AND A CURRENT LIMITING RESISTOR ADAPTED TO BE CONNECTED TO SAID SOURCE OF SUPPLY POTENTIAL, COLLECTOR LOAD RESISTORS COUPLING THE COLLECTOR ELECTRODES OF EACH OF SAID TRANSISTORS TO SAID VOLTAGE REGULATOR, BASE BIASING RESISTORS COUPLING THE BASE ELECTRODES OF EACH OF SAID TRANSISTORS TO SAID VOLTAGE REGULATOR, THE EMITTER ELECTRODES OF EACH OF SAID TRANSISTORS DIRECTLY CONNECTED TO ONE OF SAID PAIR OF TERMINALS OF SAID SUPPLY SOURCE, A MONITORING MEANS INCLUDING A LIGHT SOURCE CONNECTED BETWEEN SAID CURRENT LIMITING RESISTOR AND THE OTHER OF SAID PAIR OF TERMINALS OF SAID SUPPLY SOURCE, SAID MONITORING MEANS INCLUDING A PHOTO-SENSITIVE RESISTIVE ELEMENT ELECTRICALLY CONNECTED TO THE COLLECTOR ELECTRODE OF ONE OF SAID FIRST AND SECOND TRANSISTORS, A THIRD TRANSISTOR HAVING AN EMITTER, A COLLECTOR AND A BASE ELECTRODE, A VOLTAGE DIVIDER INCLUDING A PAIR OF RESISTORS CONNECTED ACROSS SAID
Claim 2
Dependent Claim
203 words
A FAIL-SAFE STANDARD AMPLITUDE SIGNAL SOURCE COMPRISING: A SOURCE OF SUPPLY POTENTIAL HAVING A PAIR OF TERMINALS, A MULTIVIBRATOR HAVING A FIRST AND A SECOND TRANSISTOR EACH HAVING AN EMITTER, A COLLECTOR AND A BASE ELECTRODE, CAPACITOR MEANS CROSS-COUPLING THE COLLECTOR ELECTRODE OF EACH OF SAID TRANSISTOR TO THE BASE ELECTRODE OF THE OTHER OF SAID TRANSISTORS, A VOLTAGE REGULATOR INCLUDING A ZENER TYPE DIODE AND A CURRENT LIMITING RESISTOR ADAPTED TO BE CONNECTED TO SAID SOURCE OF SUPPLY POTENTIAL, COLLECTOR LOAD RESISTORS COUPLING THE COLLECTOR ELECTRODES OF EACH OF SAID TRANSISTORS TO SAID VOLTAGE REGULATOR, BASE BIASING RESISTORS COUPLING THE BASE ELECTRODES OF EACH OF SAID TRANSISTORS TO SAID VOLTAGE REGULATOR, THE EMITTER ELECTRODES OF EACH OF SAID TRANSISTORS DIRECTLY CONNECTED TO ONE OF SAID PAIR OF TERMINALS OF SAID SUPPLY SOURCE, A MONITORING MEANS INCLUDING A LIGHT SOURCE CONNECTED BETWEEN SAID CURRENT LIMITING RESISTOR AND THE OTHER OF SAID PAIR OF TERMINALS OF SAID SUPPLY SOURCE, SAID MONITORING MEANS INCLUDING A PHOTO-SENSITIVE RESISTIVE ELEMENT ELECTRICALLY CONNECTED TO THE COLLECTOR ELECTRODE OF ONE OF SAID FIRST AND SECOND TRANSISTORS, A THIRD TRANSISTOR HAVING AN EMITTER, A COLLECTOR AND A BASE ELECTRODE, A VOLTAGE DIVIDER INCLUDING A PAIR OF RESISTORS CONNECTED ACROSS SAID
References Cited (Backward Citations)
US3202926A
Cited
US3360744A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1971-09-10 | 1972-03-11 | 1972-09-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1975-09-10 | 1976-03-11 | 1976-09-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1979-09-10 | 1980-03-11 | 1980-09-10 | $7700.00 | Window Closed / Lapsed |