US4429186A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Floating battery feed circuit for telephone subscriber line interface
Assignee: QUADRUM SA DE CV A CORP OF MEXICO
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Filing: 1982-09-30
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Granted: 1984-01-31
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Expires: 2002-09-30
Abstract
Abstract An arrangement for providing a subscriber line with an operating potential. The energy to the line is transferred thereto inductively at a fixed frequency and includes the rectification means on the subscriber side of the inductor. The amount of energy transferred to the line is controlled by pulse width. The control pulse width circuit includes means to decrease the energy transfer above a level at which a subscriber station internal regulation would be defeated.
Inventors
- 👤 Todd H. Gartner
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 16:19
CPC Classifications
H; H04; H04M; H04M19/00; H04M19/001; H04M19/008; Y; Y02; Y02D; Y02D30/00; Y02D30/70
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
117 words
A circuit operated in synchronism with an external pulse source for supplying and monitoring direct current in a transformer isolated line comprising: a transformer having an input winding and an output winding; a capacitor connected across said output winding; a rectifier connected between said output winding and said capacitor with said line connected across said capacitor for receiving an operating potential; a pulse width voltage coverter operated in response to said pulse source to output a power pulse through said input winding; and a first negative peak voltage detector connected to said input winding operated to condition said converter to increase the duration of said power pulse upon sensing a negative peak voltage below a predetermined level.
Claim 2
Dependent Claim
117 words
A circuit operated in synchronism with an external pulse source for supplying and monitoring direct current in a transformer isolated line comprising: a transformer having an input winding and an output winding; a capacitor connected across said output winding; a rectifier connected between said output winding and said capacitor with said line connected across said capacitor for receiving an operating potential; a pulse width voltage coverter operated in response to said pulse source to output a power pulse through said input winding; and a first negative peak voltage detector connected to said input winding operated to condition said converter to increase the duration of said power pulse upon sensing a negative peak voltage below a predetermined level.
Claim 3
Dependent Claim
45 words
A circuit as claimed in claim 1, wherein said transformer further includes a sense winding and a second peak voltage detector connected to said sense winding operated upon detecting a second predetermined voltage level to control said converter to decrease the rate of voltage increase.
Claim 4
Dependent Claim
32 words
A circuit as claimed in claim 2 further including a resistor network between said first and second peak voltage detectors and said converter operated to proportion the effective control of said converter.
Claim 5
Dependent Claim
29 words
A circuit as claimed in claim 3 further including a zener diode between said second peak voltage detector and said resistor network to set said second predetermined voltage level.
Claim 6
Dependent Claim
41 words
A circuit as claimed in claim 2 or 4 further including a shutdown means connected between said second peak voltage detector and said converter operated upon said second peak voltage detector indicating a third voltage level to shut down said converter.
Claim 7
Dependent Claim
37 words
A circuit as claimed in claim 2 further including dial pulse detection means comprising an amplifier controlled by said second peak detector sensing voltage changes due to line interruptions reflected into said sense-winding to repeat said signals.
References Cited (Backward Citations)
US4056691A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-01-30 | 1987-08-01 | 1988-01-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-01-30 | 1991-08-01 | 1992-01-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-01-30 | 1995-08-01 | 1996-01-31 | $7700.00 | Window Closed / Lapsed |