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US4943997A Expired / Lapsed US ⏱️ 0.0 years remaining

Device for communicating a doorside intercom set with a remote telephone

Assignee: Individual
•
Filing: 1989-04-14
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Granted: 1990-07-24
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Expires: 2009-04-14
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Abstract

Abstract A device is disclosed for communicating a doorside intercom set of an intercom system with a selected forwarding telephone, having a microprocessor and an input for inputting the telephone number of the selected remote telephone. To detect the state of the selected remote telephone, a back-ring/busy tone detector is provided. To enable a host to remotely change the number of the selected remote telephone, a multiple frequency signal decoder and a ring detector is provided.

Inventors

  • 👤 Mei-Yin Chang

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-30 07:06
CPC Classifications
H; H04; H04M; H04M1/00; H04M1/26; H04M1/27; H04M1/272; H04M1/2725; H04M1/71; H04M11/00; H04M11/02; H04M11/025; H04M1/02; H04M1/0291

Claims Analysis

Total Claims: 5
Claim 1
Independent Claim 199 words
A device for communicating a doorside intercom set having a push button of an intercom system with a selected remote telephone via a cable, comprising a microprocessor with a software and memory means, an input means for inputting the phone number of said selected remote telephone into said memory means, and detecting means to detect the state of said selected remote telephone; said software being so programmed that when said push button is pushed, said microprocessor will read the phone number from said memory means and send out a corresponding signal via said cable to give a call to said selected remote telephone to build up the communication between said doorside intercom set and said selected remote telephone when said selected remote telephone is detected by said detecting means as not busy, said device further comprising a number changing means for changing the number of said selected remote telephone stored in said memory means, said number changing means being only actuated to receive a new telephone number inputted by dialing from any remote telephone via said cable to said device after a specific password code is inputted by dialing said any remote telephone via said cable to said device.
Claim 2
Independent Claim 199 words
A device for communicating a doorside intercom set having a push button of an intercom system with a selected remote telephone via a cable, comprising a microprocessor with a software and memory means, an input means for inputting the phone number of said selected remote telephone into said memory means, and detecting means to detect the state of said selected remote telephone; said software being so programmed that when said push button is pushed, said microprocessor will read the phone number from said memory means and send out a corresponding signal via said cable to give a call to said selected remote telephone to build up the communication between said doorside intercom set and said selected remote telephone when said selected remote telephone is detected by said detecting means as not busy, said device further comprising a number changing means for changing the number of said selected remote telephone stored in said memory means, said number changing means being only actuated to receive a new telephone number inputted by dialing from any remote telephone via said cable to said device after a specific password code is inputted by dialing said any remote telephone via said cable to said device.
Claim 3
Dependent Claim 22 words
The device according to claim 1 wherein said microprocessor will stop said call when said selected remote telephone is detected as busy.
Claim 4
Dependent Claim 22 words
The device according to claim 2, wherein said microprocessor stops said call immediately when said selected remote telephone is detected as busy.
Claim 5
Dependent Claim 27 words
The device according to claim 2, wherein said microprocessor stops said call after a predetermined number of times when said selected remote telephone is detected as busy.

References Cited (Backward Citations)

US4764953A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1993-07-23 1994-01-22 1994-07-24 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1997-07-23 1998-01-22 1998-07-24 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2001-07-23 2002-01-22 2002-07-24 $7700.00 Window Closed / Lapsed

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