Patent US3716834A successfully refreshed from Google Patents.
US3716834A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Data transmission system with immunity to circuit faults
Assignee: Individual
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Filing: 1971-10-07
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Granted: 1973-02-13
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Expires: 1991-10-07
Abstract
Abstract A system for use with a data transmission network having a central station and a plurality of remote stations connected in series by a low grade transmission line such as a telephone pair. The system of the invention is immune to common transmission line faults, such as a line to ground short, a line open circuit, a line to line short, etc. and will continue to operate in spite of such faults. The system is also capable of identifying a transmission line fault when it occurs, the nature of the fault, and the approximate location of the fault in the network.
Inventors
- 👤 H Adams
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 22:41
CPC Classifications
G; G08; G08B; G08B29/00; G08B29/16; G08B26/00; G08B26/005
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
194 words
A system for use with a transmission line comprising a central station adapted to be connected to the ends of said transmission line, and including means for impressing electric signals on both ends of said line, said central station including means for transmitting information into said transmission line by varying the signals applied to both ends of said transmission line; a plurality of two-terminal remote stations adapted to be connected in series by said transmission line, said remote station including means responsive to said signals received at either terminal of said remote stations, and said remote stations including means responsive to said varying signals for providing information to said central station by altering the electric signal at the terminals of said remote stations; and said central station including means for receiving said information from said remote stations via said transmission line by sensing the altering of said electrical signals as received at each end of said transmission line whereby in addition to transmitting information in the system a fault in the transmission path may be identified by comparison of the signals simultaneously received at both ends of the transmitted line at the central station.
Claim 2
Independent Claim
194 words
A system for use with a transmission line comprising a central station adapted to be connected to the ends of said transmission line, and including means for impressing electric signals on both ends of said line, said central station including means for transmitting information into said transmission line by varying the signals applied to both ends of said transmission line; a plurality of two-terminal remote stations adapted to be connected in series by said transmission line, said remote station including means responsive to said signals received at either terminal of said remote stations, and said remote stations including means responsive to said varying signals for providing information to said central station by altering the electric signal at the terminals of said remote stations; and said central station including means for receiving said information from said remote stations via said transmission line by sensing the altering of said electrical signals as received at each end of said transmission line whereby in addition to transmitting information in the system a fault in the transmission path may be identified by comparison of the signals simultaneously received at both ends of the transmitted line at the central station.
Claim 3
Independent Claim
194 words
A system for use with a transmission line comprising a central station adapted to be connected to the ends of said transmission line, and including means for impressing electric signals on both ends of said line, said central station including means for transmitting information into said transmission line by varying the signals applied to both ends of said transmission line; a plurality of two-terminal remote stations adapted to be connected in series by said transmission line, said remote station including means responsive to said signals received at either terminal of said remote stations, and said remote stations including means responsive to said varying signals for providing information to said central station by altering the electric signal at the terminals of said remote stations; and said central station including means for receiving said information from said remote stations via said transmission line by sensing the altering of said electrical signals as received at each end of said transmission line whereby in addition to transmitting information in the system a fault in the transmission path may be identified by comparison of the signals simultaneously received at both ends of the transmitted line at the central station.
Claim 4
Independent Claim
194 words
A system for use with a transmission line comprising a central station adapted to be connected to the ends of said transmission line, and including means for impressing electric signals on both ends of said line, said central station including means for transmitting information into said transmission line by varying the signals applied to both ends of said transmission line; a plurality of two-terminal remote stations adapted to be connected in series by said transmission line, said remote station including means responsive to said signals received at either terminal of said remote stations, and said remote stations including means responsive to said varying signals for providing information to said central station by altering the electric signal at the terminals of said remote stations; and said central station including means for receiving said information from said remote stations via said transmission line by sensing the altering of said electrical signals as received at each end of said transmission line whereby in addition to transmitting information in the system a fault in the transmission path may be identified by comparison of the signals simultaneously received at both ends of the transmitted line at the central station.
Claim 5
Dependent Claim
74 words
A system according to claim 1 wherein said electric signals are non-identical signals and further comprising means for connecting said stations to a source of reference potential, said central station transmitting means including pulsing means for switching both ends of said transmission line from said electric signals to said reference potential, and said remote stations responsive means altering said electric signal by interrupting the Current flow of said electric signal in said transmitting line.
Claim 6
Dependent Claim
28 words
A system according to claim 2 wherein said remote stations responsive means for interrupting the current flow in said transmitting path includes a first switch, in transmission line.
Claim 7
Dependent Claim
81 words
A system according to claim 3 wherein there is connected in parallel with said switch a series combination of a pair of diodes poled in the same direction, two switches, and means for making connection to the reference potential, said diodes being poled in a direction to oppose normal current flow of said electric signal and said switches normally being closed but being operated when said first switch is opened, one of said switches being connected to each of said diodes.
Claim 8
Dependent Claim
28 words
A system according to claim 4 wherein said central station further includes a polarity reversing switch for interchanging said electric signals applied at said ends of said line.
Claim 9
Dependent Claim
29 words
A system according to claim 5 further including means for operating said polarity reversing in response to failure of said electric signal to normally flow in said transmission line.
Claim 10
Dependent Claim
29 words
A system according to claim 5 wherein said central station includes switches in each of said transmission lines for selectively interrupting said electric signal in each of said lines.
Claim 11
Dependent Claim
42 words
A system according to claim 4 wherein said detection means further includes means for comparing the simultaneous receipt of signals from said remote stations, and providing a warning signal when said signals are not received on both sides of the transmission line.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-02-13 | 1976-08-14 | 1977-02-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-02-13 | 1980-08-14 | 1981-02-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-02-13 | 1984-08-14 | 1985-02-13 | $7700.00 | Window Closed / Lapsed |