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US3578917A Expired / Lapsed US ⏱️ 0.0 years remaining

Security circuit for multi-exchange telecommunication network

Assignee: International Standard Electric Corp
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Filing: 1969-06-16
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Granted: 1971-05-18
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Expires: 1989-06-16
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Abstract

Abstract In a telephone exchange comprising a central processor serving several satellite exchanges, a satellite is completely blocked when the cable which connects it to the processor is out of order. According to the invention, each pair of satellites is interconnected by means of a single communication channel so that the transfer of data between the processor and the satellite whose cable is out of order may be effected via another satellite.

Inventors

  • 👤 Charles Henri Emile Grandjean
  • 👤 Jean Perrault

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-23 00:41
CPC Classifications
H; H04; H04Q; H04Q3/00; H04Q3/42; H04Q3/54; H04Q3/545

Claims Analysis

Total Claims: 6
Claim 1
Independent Claim 140 words
A telecommunications network comprising a main switching center having a data processor thereat, a plurality of satellite exchanges, means at each of said satellite exchanges operated responsive to commands from the data processor, a separate multichannel cable connecting each to said main center, one of the channels of each cable being a service channel reserved for the interchange of information between said data processor and equipment at the satellite exchange served by the cable carrying the service channel, a cable connecting one of said satellite exchanges to another one of said exchanges, and means at one satellite exchange responsive to a signal received over the service channel from said main center indicating a trouble condition between said center and another satellite exchange for coupling said main center through said one satellite exchange to said other satelliTe exchange over said cable.
Claim 2
Dependent Claim 140 words
A telecommunications network comprising a main switching center having a data processor thereat, a plurality of satellite exchanges, means at each of said satellite exchanges operated responsive to commands from the data processor, a separate multichannel cable connecting each to said main center, one of the channels of each cable being a service channel reserved for the interchange of information between said data processor and equipment at the satellite exchange served by the cable carrying the service channel, a cable connecting one of said satellite exchanges to another one of said exchanges, and means at one satellite exchange responsive to a signal received over the service channel from said main center indicating a trouble condition between said center and another satellite exchange for coupling said main center through said one satellite exchange to said other satelliTe exchange over said cable.
Claim 3
Dependent Claim 26 words
A network as claimed in claim 1, wherein said satellite exchanges are connected in pairs with an emergency service channel running between the paired satellite exchanges.
Claim 4
Dependent Claim 30 words
A network as claimed in claim 1, wherein said satellite exchanges are interconnected in groups of three by two emergency channels when there are an even number of satellite exchanges.
Claim 5
Dependent Claim 101 words
A network as claimed in claim 1, wherein other of said channels of each cable comprise voice channels, and said coupling means include switching means at said one satellite exchange responsive to said trouble on a service channel between the main center and said other satellite exchange for remotely operating said switching means to connect one of the voice channels at said one satellite exchange to an emergency service channel between said one and said other satellite exchanges for thereafter transmitting data between said main center and other first satellite exchange via said emergency service channel and said connected voice channel.
Claim 6
Dependent Claim 36 words
A network as claimed in claim 1, further including reset means at said one satellite responsive to a signal from said main center for resetting said coupling means to decouple said one exchange from said other.

References Cited (Backward Citations)

CA803621A Cited
US3524940A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1974-05-17 1974-11-16 1975-05-18 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1978-05-17 1978-11-16 1979-05-18 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1982-05-17 1982-11-16 1983-05-18 $7700.00 Window Closed / Lapsed

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