US4277647A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Coin signaling system
Assignee: AT&T Inc
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Filing: 1979-08-31
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Granted: 1981-07-07
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Expires: 1999-08-31
Abstract
Abstract A subscriber loop carrier system is shown in which coin first and dial tone first pay stations can be serviced through the carrier system without modifying the central office. Coin supervisory states are detected at the central office terminal of the system, translated into unique cyclic codes for transmission through the system and detected at the remote terminal by reapplication of the coin supervisory states at the remote terminal. Coin first and dial tone first modes of operation are accommodated with simple option plugs.
Inventors
- 👤 Stephen J. Brolin
- 👤 Samuel Colodner
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 08:24
CPC Classifications
H; H04; H04M; H04M17/00; H04M17/02; H04M17/023
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
97 words
A coin supervisory signal detector for central office wire pairs in a telephone system characterized by voltage detection means for detecting the magnitude and polarity of voltages appearing on said wire pairs, a plurality of optical isolators for detecting the direction of current flow in each wire of said wire pairs, and combinatorial logic circuit means for combining the outputs of said voltage detection means and the outputs of said isolators to provide separate indications of each of a plurality of unique coin supervisory signaling states to be transmitted to a remote location in said telephone system.
Claim 2
Dependent Claim
97 words
A coin supervisory signal detector for central office wire pairs in a telephone system characterized by voltage detection means for detecting the magnitude and polarity of voltages appearing on said wire pairs, a plurality of optical isolators for detecting the direction of current flow in each wire of said wire pairs, and combinatorial logic circuit means for combining the outputs of said voltage detection means and the outputs of said isolators to provide separate indications of each of a plurality of unique coin supervisory signaling states to be transmitted to a remote location in said telephone system.
Claim 3
Dependent Claim
24 words
The supervisory signal detector according to claim 1 further characterized in that said voltage detection means comprises means for detecting central office talking voltages.
Claim 4
Dependent Claim
25 words
The supervisory signal detector according to claim 1 further characterized in that said voltage detection means comprises means for detecting central office coin control voltages.
Claim 5
Dependent Claim
30 words
The supervisory signal detector according to claim 1 further characterized in that said plurality of optical isolators comprises two oppositely poled isolators connected in series with each of said wires.
Claim 6
Dependent Claim
36 words
The supervisory signal detector according to claim 1 further characterized in that said combinatorial logic circuit means includes optional selecting means for selectively providing coin first supervisory signal detection or dial tone first supervisory signal detection.
Claim 7
Dependent Claim
35 words
The supervisory signal detection according to claim 1 further characterized in that said combinatorial logic circuit means includes means for converting a plurality of coin supervisory signals into a lesser plurality of transmission control signals.
Claim 8
Dependent Claim
123 words
In a subscriber loop carrier system for establishing a plurality of subscriber channels over a lesser plurality of transmission lines, means for deriving at least one coin station channel over said carrier system, said deriving means characterized by means including a plurality of optical isolators for detecting a plurality of coin supervisory states established at the central office end of one channel of said system, means including combinatorial logic circuits for encoding said plurality of supervisory states into a lesser plurality of cyclic transmission codes for transmission over said system, and means at the remote end of said system and responsive to said transmission codes for replicating said coin supervisory states on a coin station loop at said remote end of said system.
Claim 9
Dependent Claim
123 words
In a subscriber loop carrier system for establishing a plurality of subscriber channels over a lesser plurality of transmission lines, means for deriving at least one coin station channel over said carrier system, said deriving means characterized by means including a plurality of optical isolators for detecting a plurality of coin supervisory states established at the central office end of one channel of said system, means including combinatorial logic circuits for encoding said plurality of supervisory states into a lesser plurality of cyclic transmission codes for transmission over said system, and means at the remote end of said system and responsive to said transmission codes for replicating said coin supervisory states on a coin station loop at said remote end of said system.
Claim 10
Dependent Claim
78 words
The combination according to claim 7 further characterized by means including a plurality of optical isolators at said remote end of said system for detecting off-hook and coin ground conditions on said coin station loop, means for encoding said off-hook and coin ground conditions for transmission to said central office end of said system, and means at said central office end of said system for replicating said off-hook and coin ground conditions for detecting at said central office.
Claim 11
Dependent Claim
31 words
The combination according to claim 7 further characterized in that said coin supervisory state detecting means includes means for selectively detecting coin first supervisory states or dial tone first supervisory states.
Claim 12
Dependent Claim
67 words
The combination according to claim 7 further characterized in that said coin supervisory state detecting means comprises means for detecting the magnitude and polarity of voltages at said central office end, said optical isolators comprising means for detecting the direction of current flow in each wire of said one channel, and means for logically combining the outputs of said voltage detecting means and said optical isolating means.
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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) | 1984-07-06 | 1985-01-05 | 1985-07-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-07-06 | 1989-01-05 | 1989-07-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-07-06 | 1993-01-05 | 1993-07-07 | $7700.00 | Window Closed / Lapsed |