US3842334A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Oscillator circuit for providing a failsafe direct current voltage output in response to a periodic signal input
Assignee: Bombardier Transportation Holdings USA Inc
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Filing: 1973-05-11
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Granted: 1974-10-15
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Expires: 1993-05-11
Abstract
Abstract An oscillator provides a signal output only in response to the detection of a provided periodic signal. The signal output of the oscillator is rectified to produce a failsafe energization signal for a load device such as a relay or the like.
Inventors
- 👤 J Franz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 16:02
CPC Classifications
H; H02; H02M; H02M3/00; H02M3/22; H02M3/24; H02M3/28; H02M3/325; H02M3/335; H02M3/337; H02M3/3376; H02M3/3378; B; B61; B61L; B61L1/00; B61L1/20
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
349 words
A failsafe driver comprising: means for providing a periodic signal; a detector for providing a first direct current signal in response to the provision of said periodic signal; an oscillator comprising first and second transistors, each having base, emitter and collector electrodes, with the base electrode of each being connected to a first reference potential and one of the emitter or collector of each being connected together and also being connected to said detector for receiving said first direct current signal; third and fourth transistors each comprising an amplifier, and each having base, emitter and collector electrodes, with the base electrode of the third being connected to the remaining one of the emitter or collector electrode of said first transistor, and the base electrode of the fourth being connected to the remaining one of the emitter or collector electrode of said second transistor, and one of the emitter or collector electrode of said third and fourth transistors each being connected to a second reference potential; a transformer having primary and secondary windings with each winding having at least first and second terminals, with the first terminal of the primary winding being connected to the remaining one of the emitter or collector electrode of said third transistor, and with the second terminal of the primary winding being connected to the remaining one of the emitter or collector electrode of said fourth transistor; first and second diodes each having cathode and anode electrodes, with one of the cathode and anode electrodes of each being connected together, and the remaining one of the cathode and anode electrode of the first diode being connected to the first terminal of the secondary winding of said transformer, and the remaining one of the cathode and anode electrode of the second diode being connected to the second terminal of the secondary winding of said transformer; and a signal feedback path and timing network including a capacitor connected between the remaining one of the emitter of collector electrodes of said fourth transistor and the base electrode of said second transistor for controlling the timing of said oscillator.
Claim 2
Dependent Claim
349 words
A failsafe driver comprising: means for providing a periodic signal; a detector for providing a first direct current signal in response to the provision of said periodic signal; an oscillator comprising first and second transistors, each having base, emitter and collector electrodes, with the base electrode of each being connected to a first reference potential and one of the emitter or collector of each being connected together and also being connected to said detector for receiving said first direct current signal; third and fourth transistors each comprising an amplifier, and each having base, emitter and collector electrodes, with the base electrode of the third being connected to the remaining one of the emitter or collector electrode of said first transistor, and the base electrode of the fourth being connected to the remaining one of the emitter or collector electrode of said second transistor, and one of the emitter or collector electrode of said third and fourth transistors each being connected to a second reference potential; a transformer having primary and secondary windings with each winding having at least first and second terminals, with the first terminal of the primary winding being connected to the remaining one of the emitter or collector electrode of said third transistor, and with the second terminal of the primary winding being connected to the remaining one of the emitter or collector electrode of said fourth transistor; first and second diodes each having cathode and anode electrodes, with one of the cathode and anode electrodes of each being connected together, and the remaining one of the cathode and anode electrode of the first diode being connected to the first terminal of the secondary winding of said transformer, and the remaining one of the cathode and anode electrode of the second diode being connected to the second terminal of the secondary winding of said transformer; and a signal feedback path and timing network including a capacitor connected between the remaining one of the emitter of collector electrodes of said fourth transistor and the base electrode of said second transistor for controlling the timing of said oscillator.
Claim 3
Dependent Claim
59 words
The combination claimed in claim 1 including: a capacitor having four terminals, with the first terminal being connected to the common connection of said first and second diodes, and the second terminal being connected to the third terminal of the secondary winding of said transformer; and a load device connected across the third and fourth terMinals of said capacitor.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-10-14 | 1978-04-15 | 1978-10-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-10-14 | 1982-04-15 | 1982-10-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-10-14 | 1986-04-15 | 1986-10-15 | $7700.00 | Window Closed / Lapsed |