Patent US3787679A successfully refreshed from Google Patents.
US3787679A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Train communication system
Assignee: British Railways Board
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Filing: 1972-01-26
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Granted: 1974-01-22
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Expires: 1992-01-26
Abstract
Abstract This invention relates to a train communication system in which trackside transponder devices containing coded information as to track gradient, speed restrictions etc, pass this information to receiver equipment on the train on receipt of an activating signal from a transmitter on the train. The system is operative to declare a fault if a transponder, at an expected location for said transponder, fails to respond to the activating signal so as to fail to pass information to the receiver equipment.
Inventors
- 👤 M Birkin
- 👤 W Parkman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 01:42
CPC Classifications
B; B61; B61L; B61L3/00; B61L3/02; B61L3/08; B61L3/12; B61L3/121
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
180 words
A train communication system comprising a track having a train moving thereon, said train carrying a transmitter and a receiver, at least one transponder mounted adjacent the track, said transmitter being operative to transmit an activating signal for activating said transponder when said train passes said transponder, said transponder, when so activated, being operative to transmit data contained therein to the receiver carried on the passing train, a fail-safe triggering device associated with each transponder for transmitting a signal to said train operative to trigger said receiver on said train to render said receiver operative to accept said data from said transponder, and means responsive to the failure of a transponder to respond to the activating signal from said transmitter after reception by said receiver of a signal from said triggering device for declaring a fault, said last-named means including a program device carried by said train to provide information regarding the expected location of each transponder whereby the failure of a transponder at the expected location to respond to the activating signal will result in a fault being declared.
Claim 2
Dependent Claim
180 words
A train communication system comprising a track having a train moving thereon, said train carrying a transmitter and a receiver, at least one transponder mounted adjacent the track, said transmitter being operative to transmit an activating signal for activating said transponder when said train passes said transponder, said transponder, when so activated, being operative to transmit data contained therein to the receiver carried on the passing train, a fail-safe triggering device associated with each transponder for transmitting a signal to said train operative to trigger said receiver on said train to render said receiver operative to accept said data from said transponder, and means responsive to the failure of a transponder to respond to the activating signal from said transmitter after reception by said receiver of a signal from said triggering device for declaring a fault, said last-named means including a program device carried by said train to provide information regarding the expected location of each transponder whereby the failure of a transponder at the expected location to respond to the activating signal will result in a fault being declared.
Claim 3
Dependent Claim
41 words
The train communication system of claim 1 wherein said system comprises a plurality of said transponders disposed in spaced relation to one another along the track, the spacing between adjacent transponders being such as to provide a required resolution of data.
Claim 4
Dependent Claim
35 words
The train communication system of claim 1 wherein said fail-safe triggering device comprises a permanent magnet located adjacent said transponder, and detector means carried by said train responsive to the presence of said permanent magnet.
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) | 1977-01-21 | 1977-07-23 | 1978-01-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-01-21 | 1981-07-23 | 1982-01-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-01-21 | 1985-07-23 | 1986-01-22 | $7700.00 | Window Closed / Lapsed |