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US5097501A Expired / Lapsed US ⏱️ 0.0 years remaining

Key telephone interface

Assignee: Avaya Inc
•
Filing: 1990-06-29
•
Granted: 1992-03-17
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Expires: 2010-06-29
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Abstract

Abstract Apparatus is disclosed for use in a key set interface to overcome the incompatibility between key sets and tip and ring devices. The interface apparatus rejects ringing voltage and tip and ring loop current intended to be supplied on a first pair of conductors, the TR-pair. The interface further includes apparatus adapted for bi-directional communication of supervisory and control signals. In a preferred embodiment of the invention, a second pair of conductors, the service pair, transports bi-directional supervisory and control signals as well as operating power supplied by a key system controller for non-TR devices. Additionally, a transceiver adapted for sending and receiving voiceband information over the first pair of conductors is incorporated into the interface. An advantage of this key set interface is that operation of a key telephone set does not interfere with the operation of a tip and ring device bridged onto the first conductor pair.

Inventors

  • 👤 Walter G. Kutzavitch

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-26 06:26
CPC Classifications
H; H04; H04M; H04M3/00; H04M9/00; H04M9/002; H04M9/005; H04M9/006; H04M9/003; H04M3/02; H04M3/42; H04M3/42314

Claims Analysis

Total Claims: 10
Claim 1
Independent Claim 74 words
Apparatus in a key telephone station set or enhanced functionality station unit adapted to be connected via an at least first conductor pair for communicating with a telephone switching system control unit comprising: means for rejecting tip and ring ringing signal supplied from said first conductor pair; means for rejecting loop current, greater than a predetermined value, supplied from said first conductor pair; and means adapted for transmitting and receiving supervisory and control signals.
Claim 2
Dependent Claim 74 words
Apparatus in a key telephone station set or enhanced functionality station unit adapted to be connected via an at least first conductor pair for communicating with a telephone switching system control unit comprising: means for rejecting tip and ring ringing signal supplied from said first conductor pair; means for rejecting loop current, greater than a predetermined value, supplied from said first conductor pair; and means adapted for transmitting and receiving supervisory and control signals.
Claim 3
Dependent Claim 30 words
The invention as described in claim 1 wherein said means adapted for transmitting and receiving transmits and receives said supervisory and control signals over an at least second conductor pair.
Claim 4
Dependent Claim 25 words
The invention as described in claim 1 wherein said apparatus further includes means adapted for transmitting and receiving voiceband communication over said first conductor pair.
Claim 5
Dependent Claim 32 words
The apparatus as defined in claim 3 further including means responsive to a control signal for inhibiting access to said first conductor pair by said means for transmitting and receiving voiceband communication.
Claim 6
Dependent Claim 32 words
The apparatus as defined in claim 4 wherein said means for inhibiting includes means responsive to special signaling messages from said means adapted for transmitting and receiving said supervisory and control signals.
Claim 7
Dependent Claim 26 words
The apparatus as defined in claim 2 further including means adapted for obtaining operating power intended to be supplied from an at least third conductor pair.
Claim 8
Dependent Claim 17 words
The apparatus as defined in claim 2 wherein said signaling on said second conductor pair is differential.
Claim 9
Dependent Claim 23 words
The apparatus as defined in claim 2 further including means adapted for obtaining operating power supplied from said at least second conductor pair.
Claim 10
Dependent Claim 36 words
The apparatus as defined in claim 8 further including polarity guard means adapted for providing insensitivity to the polarity of said signals and said power intended to be supplied from said at least second conductor pair.

References Cited (Backward Citations)

US4088846A Cited
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US4363936A Cited
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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) 1995-03-17 1995-09-16 1996-03-17 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1999-03-17 1999-09-16 2000-03-17 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2003-03-17 2003-09-16 2004-03-17 $7700.00 Window Closed / Lapsed

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