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US3867573A
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Track to train communication systems
Assignee: British Railways Board
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Filing: 1971-10-12
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Granted: 1975-02-18
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Expires: 1991-10-12
Abstract
Abstract A transmitter for use in signalling systems for example in track to train communication systems for transmitting information in digital code. The transmitter comprises a plurality of read-only memories each having a stored information content related to a respective state of a variable. Control means are responsive to the state of the variable for causing the output of the one of the read-only memories related to the prevailing state of the variable to be transmitted by the transmitter.
Inventors
- 👤 Michael Sambrook Birkin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 07:58
CPC Classifications
B; B61; B61L; B61L3/00; B61L3/16; B61L3/22; B61L3/225
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
119 words
In a track-to-train communication system for transmitting information to a train related to the control of the running of the train in dependence upon the prevailing one of a plurality of signal aspects, signal indicating means controlled to one of a plurality of conditions to indicate a prevailing one of a plurality of signal aspects, a transmitter, having an output, for transmitting said information in digital code and comprising a plurality of nondestruct read-only memories each having stored therein information related to a respective one of a plurality of signal apsects, and control means responsive to said indicating means for causing information stored in the one of the read-only memories related to the prevailing signal aspect to be transmitted.
Claim 2
Dependent Claim
119 words
In a track-to-train communication system for transmitting information to a train related to the control of the running of the train in dependence upon the prevailing one of a plurality of signal aspects, signal indicating means controlled to one of a plurality of conditions to indicate a prevailing one of a plurality of signal aspects, a transmitter, having an output, for transmitting said information in digital code and comprising a plurality of nondestruct read-only memories each having stored therein information related to a respective one of a plurality of signal apsects, and control means responsive to said indicating means for causing information stored in the one of the read-only memories related to the prevailing signal aspect to be transmitted.
Claim 3
Dependent Claim
44 words
The system of claim 1 wherein all said read-only memories are simultaneously active and said control means comprises switching means for connecting the output of the one of the read-only mEmories related to the prevailing signal aspect to said output circuit of said transmitter.
References Cited (Backward Citations)
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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) | 1978-02-17 | 1978-08-19 | 1979-02-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-02-17 | 1982-08-19 | 1983-02-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-02-17 | 1986-08-19 | 1987-02-18 | $7700.00 | Window Closed / Lapsed |