US4143250A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Telephone isolation system
Assignee: TII Corp
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Filing: 1976-12-13
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Granted: 1979-03-06
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Expires: 1996-12-13
Abstract
Abstract The system disclosed transiently disconnects a subscriber's telephone equipment and network from the service provider (e.g. telephone company) network for a predetermined period of time in response to a remote switching pulse to facilitate the execution of diagnostic measurements without the necessity of visiting the subscriber's premises. The disconnect action is carried out by a two stage solid state circuit incorporating gate controlled devices such as SCRs together with RC networks whereby a capacitance is charged in response to the remotely originated switching pulse and then discharges to energize a switching relay and to maintain it energized for a predetermined period. In the energized state the switching relay isolates the subscriber network and its equipment from the telephone company network to permit the diagnostic measurements. The circuit design also provides improved noise suppression, as well as protection against spurious switching and certain overvoltage conditions. A modified version also provides means for detecting certain tip short conditions.
Inventors
- 👤 Frank L. Simokat
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 02:01
CPC Classifications
H; H04; H04M; H04M3/00; H04M3/22; H04M3/26; H04M3/28; H04M3/30; H04M3/301
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
187 words
For use in a system between a communication provider and a subscriber of the type which includes a provider network and a respective subscriber network, and wherein said provider network includes means for transmitting diagnostic switching signals to said subscriber network, an isolation system for responding to said disagnostic switching signals to transiently disconnect said subscriber network from said provider network, said isolation system comprising: (1) switching means connecting said provider network to said subscriber network in one state and disconnecting said networks in a second state; (2) a first switch control circuit connected to said provider network and having (a) pulse responsive means connected to respond to a short duration diagnostic switching signal, and (b) energy storage means responsive to said pulse responsive means; (3) a second switch control circuit including a controlled rectifier having a control circuit connected to be responsive to said energy storage means and an output circuit connected to control actuation of said switching means; and (4) a charge circuit connected to said energy storage means for maintaining a charge on said energy storage means during periods when said networks are interconnected.
Claim 2
Dependent Claim
187 words
For use in a system between a communication provider and a subscriber of the type which includes a provider network and a respective subscriber network, and wherein said provider network includes means for transmitting diagnostic switching signals to said subscriber network, an isolation system for responding to said disagnostic switching signals to transiently disconnect said subscriber network from said provider network, said isolation system comprising: (1) switching means connecting said provider network to said subscriber network in one state and disconnecting said networks in a second state; (2) a first switch control circuit connected to said provider network and having (a) pulse responsive means connected to respond to a short duration diagnostic switching signal, and (b) energy storage means responsive to said pulse responsive means; (3) a second switch control circuit including a controlled rectifier having a control circuit connected to be responsive to said energy storage means and an output circuit connected to control actuation of said switching means; and (4) a charge circuit connected to said energy storage means for maintaining a charge on said energy storage means during periods when said networks are interconnected.
Claim 3
Dependent Claim
162 words
For use in a system between a communication provider and a subscriber of the type which includes a provider network and a respective subscriber network and wherein said provider network includes means for transmitting diagnostic switching signals to said subscriber network, a disconnect system for responding to said diagnostic switching signals to transiently disconnect said subscriber network from said provider network, said disconnect system comprising: (1) switching means normally connecting said provider network to said subscriber network in one state and disconnecting said networks in a second state, (2) switch control means including a capacitance discharge circuit connected to said switching means for controlling the state thereof, said capacitance discharge circuit having a time constant in excess of ten seconds, whereby said networks may be isolated from one another for substantial periods to facilitate diagnostic testing; and (3) a capacitance connected in said capacitance discharge circuit and means for maintaining a charge on said capacitance during periods when said networks are interconnected.
Claim 4
Dependent Claim
162 words
For use in a system between a communication provider and a subscriber of the type which includes a provider network and a respective subscriber network and wherein said provider network includes means for transmitting diagnostic switching signals to said subscriber network, a disconnect system for responding to said diagnostic switching signals to transiently disconnect said subscriber network from said provider network, said disconnect system comprising: (1) switching means normally connecting said provider network to said subscriber network in one state and disconnecting said networks in a second state, (2) switch control means including a capacitance discharge circuit connected to said switching means for controlling the state thereof, said capacitance discharge circuit having a time constant in excess of ten seconds, whereby said networks may be isolated from one another for substantial periods to facilitate diagnostic testing; and (3) a capacitance connected in said capacitance discharge circuit and means for maintaining a charge on said capacitance during periods when said networks are interconnected.
Claim 5
Dependent Claim
147 words
For use in a system between a communication provider and a subscriber of the type which includes a provider network and a respective subscriber network and wherein said provider network includes means for transmitting diagnostic switching signals to said subscriber network, a disconnect system for responding to said diagnostic switching signals to transiently disconnect said subscriber network from said provider network, said disconnect system comprising: (1) switching means normally connecting said provider network to said subscriber network in one state and disconnecting said networks in a second state, and (2) switch control means including a capacitance discharge circuit connected to said switching means for controlling the state thereof, said switch control means includes a capacitance in said discharge circuit and further includes means connected to said provider network and said subscriber network for maintaining a charge of said capacitance during the periods when said networks are interconnected.
Claim 6
Dependent Claim
147 words
For use in a system between a communication provider and a subscriber of the type which includes a provider network and a respective subscriber network and wherein said provider network includes means for transmitting diagnostic switching signals to said subscriber network, a disconnect system for responding to said diagnostic switching signals to transiently disconnect said subscriber network from said provider network, said disconnect system comprising: (1) switching means normally connecting said provider network to said subscriber network in one state and disconnecting said networks in a second state, and (2) switch control means including a capacitance discharge circuit connected to said switching means for controlling the state thereof, said switch control means includes a capacitance in said discharge circuit and further includes means connected to said provider network and said subscriber network for maintaining a charge of said capacitance during the periods when said networks are interconnected.
References Cited (Backward Citations)
US3739107A
Cited
US3773986A
Cited
US3909538A
Cited
US3867588A
Cited
US3912882A
Cited
US4016360A
Cited
US4041255A
Cited
US4054759A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-03-05 | 1982-09-04 | 1983-03-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-03-05 | 1986-09-04 | 1987-03-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-03-05 | 1990-09-04 | 1991-03-06 | $7700.00 | Window Closed / Lapsed |